Mosier, Oregon – June 3, 2016 Derailment Site Assessment Report

Union Pacific Railroad Company

Prepared for Oregon Department of Environmental Quality

October 28, 2016

2020 SW 4th Ave, Suite 300 Portland, OR 97201 Contents

Section Page Acronyms and Abbreviations ...... v 1 Introduction ...... 1-1 1.1 Site Description ...... 1-2 1.2 Nature of Release ...... 1-2 2 Emergency Response Procedures ...... 2-1 2.1 Columbia River Response Actions...... 2-1 2.2 Derailed Tank Car Removal and Track Repair ...... 2-1 2.3 City of Mosier Wastewater Treatment Plant Response Actions ...... 2-1 3 Incident Command Sampling ...... 3-1 3.1 Surface Water Sampling ...... 3-1 3.1.1 Surface Water Grab Sampling ...... 3-1 3.1.2 OSU Diffusion Bag Sampling ...... 3-2 3.1.3 Surface Water Analytical Results ...... 3-2 3.2 Sediment Sampling ...... 3-3 3.2.1 Sediment Sampling Approach ...... 3-3 3.2.2 Sediment Analytical Results ...... 3-3 3.3 Groundwater Sampling ...... 3-3 3.3.1 Groundwater Sampling Approach ...... 3-4 3.3.2 Groundwater Analytical Results ...... 3-4 3.4 Soil Sampling ...... 3-4 3.4.1 Initial Excavation and Confirmation Soil Samples ...... 3-5 3.4.2 Additional Soil Removal and Confirmation Sample Collection ...... 3-5 3.5 Other Response Action Sampling ...... 3-5 3.5.1 Pothole Soil Sampling Near Manhole ...... 3-5 3.5.2 Mainline Track Confirmation Soil Sampling ...... 3-6 4 Biosparge Treatment System ...... 4-1 4.1 Treatment System Design ...... 4-1 4.2 Startup ...... 4-1 4.3 Operation Monitoring ...... 4-2 5 Future Site Actions ...... 5-1 5.1 Surface Water Sampling at Rock Creek and Wetland ...... 5-1 5.2 Groundwater Sampling ...... 5-1 5.3 Soil Gas Surveying ...... 5-1 5.4 Biosparge Operations ...... 5-1 5.5 Site Restoration ...... 5-1

Appendixes A Spill Report and Incident Command Sampling Plan B Representative Site Photographs C OSU Passive Sampling Device SAP and Final Report D Previous Surface Water Sample Results E Laboratory Analytical Data Packages CONTENTS, CONTINUED

F Boring Logs G Previous Groundwater Sample Results

Tables 3-1 Columbia River and Rock Creek Surface Water Sample Results (September 7, 2016) 3-2 Columbia River Sediment Sample Results 3-3 Rock Creek Sediment Sample Results 3-4 Groundwater Sample Results (September 8 and 9, 2016) 3-5 Initial Confirmation Soil Sample Results (Soil Later Removed) 3-6 Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) 3-7 Pothole Soil Sample Results near WWTP Manhole 3-8 Mainline Track Confirmation Soil Sample Results 3-9 Miscellaneous Soil Sample Results

Figures 1-1 Site Features 1-2 Initial Response Actions 3-1 Surface Water Sampling Locations 3-2 Sediment Sampling Locations 3-3 Soil Confirmation Samples in Excavation Area (NWTPH-Dx/Gx Results) 3-4 Pothole and Mainline Track Sample Locations 4-1 Biosparge System Layout

IV EN1011161111PDX

Acronyms and Abbreviations

µg/kg microgram(s) per kilogram µg/L microgram(s) per Liter AIS air injection system BTEX benzene, toluene, ethylbenzene, and xylene DEQ Oregon Department of Environmental Quality Dx diesel range organics Gx gasoline range organics Hz hertz I-84 Interstate 84 ICS Incident Command System MDL method detection limit mg/kg milligram(s) per kilogram mg/L milligram(s) per Liter NOAA National Oceanic Atmospheric Administration NS near shore O oil range organics ORP oxidation reduction potential OS off shore OSU Oregon State University PAH polycyclic aromatic hydrocarbon PID photo-ionization detector ppm parts per million PSD passive sampling device PVC polyvinyl chloride SAP sampling and analysis plan TPH total petroleum hydrocarbon UPRR Union Pacific Railroad Company VFD variable frequency drive VOC volatile organic compound WWTP wastewater treatment plant

SECTION 1 1 Introduction

This site assessment report presents the results of surface water, sediment, wastewater treatment plant (WWTP) water, soil, and groundwater samples collected by Union Pacific Railroad Company (UPRR) in response to a derailment that resulted in a Bakken crude oil release on June 3, 2016. This site assessment report presents a summary of response measures implemented, remedial actions implemented, and the methods and rationale for the various media sampled. The report also presents information on the air biosparge treatment system installed at the site to treat groundwater in the vicinity of the release. The report is organized as follows: • Section 1.0 Introduction: This section describes the site conditions, spill location, and the nature of the release. • Section 2.0 Emergency Response Procedures: This section presents a summary of cleanup efforts conducted in response to the release. The primary efforts included initial fire response, Columbia River response actions, removal of damaged tank cars, the City of Mosier WWTP response actions, and impacted soil removal efforts. • Section 3.0 Incident Command System Sampling: This section presents the incident command system’s sampling approach and analytical results for different media including surface water, sediment, soil, WWTP water, and groundwater. • Section 4.0 Biosparge Treatment System: This section discusses the treatment system installed to treat impacted groundwater north of the release area. • Section 5.0 Future Site Actions: This section discusses future actions to be completed at the site. • Appendix A Spill Report and Incident Command Sampling Plan: This appendix contains a report that summarizes the nature of the spill, initial reporting, extent of cleanup measures implemented, and incident command sampling plan. • Appendix B Representative Site Photographs: This appendix contains representative photographs taken during the spill response and subsequent cleanup. • Appendix C Oregon State University (OSU) Passive Bag Sampling and Analysis Plan (SAP) and Final Report: This appendix includes documents developed by third-party contractor, OSU, detailing the results of deploying passive diffusion bag samplers in the Columbia River near the WWTP outfall. • Appendix D Previous Surface Water Sample Results: This appendix contains surface water sampling results pre-dating those presented in the main body of this report (prior to September 7, 2016). Comparison tables of the analytical results from the grab sampling and the OSU sampling are also presented in this appendix. • Appendix E Laboratory Analytical Data Packages: This appendix contains the laboratory analytical data packages for the samples collected in conjunction with the cleanup efforts. • Appendix F Boring Logs: Boring logs for MW-1 to MW-8, EW-1, EW-2, and BS-1 to BS-5 are included in this appendix. • Appendix G Previous Groundwater Sample Results: Groundwater sampling results prior to those presented in the main body of this report (September 8 and 9, 2016) are included in this appendix.

EN1011161111PDX 1-1 SECTION 1 – INTRODUCTION 1.1 Site Description The derailment occurred in an area west of Mosier, Oregon, in the Columbia River Gorge approximately 10 miles east of Hood River, Oregon. The area and approximate location of the derailment are shown on Figure 1-1. In this location, the tracks are located adjacent to Rock Creek Road, a segment of the Historic Columbia River Highway, and an off ramp from Interstate 84 (I-84). The derailment occurred just east of Mosier’s WWTP and west of the Highway 30 overpass from I-84. Rock Creek is located 250 feet west of derailment area and the Columbia River is approximately 600 feet north of derailment area. Two other water bodies are in the near vicinity of the derailment area: East Lake and Western Lake. Both are located between the railroad tracks and I-84 (Figure 1-1). 1.2 Nature of Release The derailment occurred on June 3, 2016, at 12:20 pm near Mosier, Oregon. Sixteen tanker cars carrying Bakken crude oil derailed. It was determined that one tanker car ignited during the derailment and two adjacent tanker cars caught fire. Up to three tanker cars released oil during the derailment. An estimated 47,000 gallons of crude oil were spilled based on manifests from loading and the amount of oil off-loaded from the derailed tanker cars. The spill area associated with this release along with response actions are shown on Figure 1-2. The derailment sheared the cover off of manhole #3 (located between extraction wells EW-1 and EW-2 on Figure 1-2), a part of a wastewater influent line that flows directly to the Mosier WWTP. Water used for the fire suppression and oil from the spill entered the wastewater influent line before the opening of the manhole could be plugged. Oily water worked its way through the WWTP and some oily water discharged via the submerged outfall to the Columbia River before the WWTP could be shut down to prevent further discharge. A sheen was observed in the Columbia River on June 4 (Figure 1-2).

1-2 EN1011161111PDX SECTION 2 2 Emergency Response Procedures

UPRR responded to the oil release along with its emergency response contractors, NRC and Clean Harbors Environmental Services (Clean Harbors). UPRR contacted the Response Management Communication Center following notification of a fuel release. The U.S. Environmental Protection Agency and the Oregon Department of Environmental Quality (DEQ) mobilized to the site on June 3, 2016. DEQ took the role of incident command lead as part of the Incident Command System (ICS). Initial response efforts included fire department response from 17 agencies and tribes; evacuation of local residents, purging and removal of sixteen tanker cars, track removal and replacement, clean-out and replacement of the City of Mosier’s WWTP equipment, excavation and disposal of impacted soil, numerous environmental sampling events, and installation and sampling of groundwater monitoring wells (shown on Figure 1-2). Appendix A contains the DEQ-required spill report. Appendix B contains representative site photographs taken during the emergency response. 2.1 Columbia River Response Actions Clean Harbors installed and maintained booms in the Columbia River during initial response activities. Both an outer and inner boom were placed near the WWTP outfall into the river (Figure 1-2). The outer boom consisted of a hard boom and the inner boom was both a hard and soft absorbent boom. Clean Harbors maintained the booms throughout the initial response activities. They also performed water quality observations and assisted with surface and sediment sampling as discussed in Section 3. 2.2 Derailed Tank Car Removal and Track Repair The derailed tank cars were assessed after fire response actions were completed on June 4, 2016. Intact tanker cars were transloaded by Clean Harbors to trucks for transport to the UPRR Dalles railyard in The Dalles, Oregon. Damaged tanker cars were cleaned on site, placed on flatbed trucks and transported to the UPRR Albina railyard in Portland, Oregon. The mainline track was repaired by UPRR and its contractors and placed back into service on June 6, 2016. 2.3 City of Mosier Wastewater Treatment Plant Response Actions Crude oil that was released from tanker cars entered the City of Mosier’s WWTP via the underground influent wastewater pipeline at manhole #3, damaged during the derailment. Approximately 247,000 gallons of oily wastewater was eventually removed from the WWTP. The oily water was containerized in nine Baker tanks and temporarily stored on site. One sample was collected from each of the nine Baker tanks containing oil-impacted water from the treatment plant. All samples were analyzed for benzene and five samples were analyzed for total petroleum hydrocarbons (TPH) (diesel, motor oil, and gasoline fractions). The complete analytical data packages are presented in Appendix E. Benzene was detected in seven of the nine samples ranging from 1 to 3,000 micrograms per Liter (µg/L). TPH was detected in all five samples analyzed. Oily water from the Baker tanks were eventually transported to Aragonite, Utah, for incineration. All necessary equipment, piping, and appurtenances in the WWTP were decontaminated by Clean Harbors and NRC and replaced by CH2M WWTP engineers, as needed. The concrete effluent line of the WWTP that runs from the plant to the Columbia River was jet-rodded to remove any possible residual oily water.

EN1011161111PDX 2-1 SECTION 2 – EMERGENCY RESPONSE PROCEDURES

While the WWTP was offline for cleaning and repairs, wastewater from the City of Mosier typically processed by the WWTP was temporary diverted and containerized in Baker tanks from June 3 through June 17, 2016. The containerized wastewater was transported on a daily basis by Clean Harbors to the Hood River WWTP. The influent line to the WWTP and a damaged manhole (Manhole #3) were eventually replaced by a City of Mosier contractor (Crestline) following soil excavation in the spill area. The influent line was replaced from manhole #4, beneath the flyover bridge entering Mosier to manhole #2 at the WWTP. The WWTP was fully operational on June 21, 2016.

2-2 EN1011161111PDX SECTION 3 3 Incident Command System Sampling

During the response action, the Environmental Unit (EU) as part of the ICS developed a Mosier Unit Train Sampling Plan dated June 13, 2016 (Appendix A). This sampling plan was revised on July 24, 2016 by DEQ. This plan describes the sampling strategy and techniques as well as the analytical methods that were employed at the site during the emergency response and subsequent remediation phase of work. The plan consists of soil sampling to support excavation activities; as well as surface water, sediment, and groundwater sampling. The sampling objectives of the Incident Command Sampling plan included the following components: • Characterize the extent and nature of contamination in various media (groundwater, sediment in river channel, surface water, and soil) • Support Unified Command decision-making regarding cleanup endpoints • Support excavation operations to determine when cleanup is complete and backfilling can commence • Ensure repeatability of sampling • Establish monitoring system that will act as a sentinel if petroleum contamination is moving towards the river • Not intended to fingerprint oil or prove that oil in environment matches spilled material. This is being handled by samples already collected. 3.1 Surface Water Sampling Surface water sampling of the Columbia River was conducted at the site beginning on the afternoon of June 5, 2016. Sampling was conducted twice per day from June 6 to 9, daily from June 10 to 17, twice per week for 1 week (June 20 and 22), and weekly (July 7 and 13). In addition, surface water samples were collected from the mouth of Rock Creek when water was present on June 10, 12, 14, 15, 16, and 27, and July 7 and 13. Samples were also collected by OSU using passive sampling devices (PSDs). This section discusses the surface water sampling approach and the laboratory results.

3.1.1 Surface Water Grab Sampling Columbia River surface water grab samples were collected from three locations in the river: upstream, downstream, and near the WWTP outfall. The surface water sample locations are identified as Upstream, Downstream, and Source and are shown on Figure 3-1. Surface water grab samples were initially collected approximately 50 to 100 feet off the shoreline via boat access. Starting in mid-June, surface water sampling of the Columbia River was collected from the shoreline as river stage was lowered allowing shoreline access to the sampling locations. Rock Creek samples were collected approximately 10 feet upstream and 10 feet downstream of the WWTP manhole located near the shoreline of the Columbia River (Figure 3-1). One surface water sample location (CR-BCH) was collected upstream of the WWTP outfall and co-located with sediment sample location SED- CR-BCH (Figure 3-1). It should be noted that surface water flow within Rock Creek and eventual discharge to the Columbia River was not occurring during this time period as the creek was dry. Surface water grab samples were collected at the mouth and approximately 30 feet upstream in Rock Creek as wind and wave driven surface water from the Columbia River entered Rock Creek.

EN1011161111PDX 3-1 SECTION 3 – INCIDENT COMMAND SYSTEM SAMPLING

The following analytical methods were used to analyze the samples: • Gasoline range petroleum hydrocarbons (NWTPH-Gx) • Diesel and oil range petroleum hydrocarbons (NWTPH-Dx) • Volatile Organic Compounds (VOCs by Method 8260) • Polycyclic aromatic hydrocarbons (PAHs by Method 8270-SIM) VOCs samples were collected by filling a laboratory provided unpreserved sample container and filling VOA bottles. All other samples were collected by directly filling laboratory supplies containers from the water surface.

3.1.2 OSU Diffusion Bag Sampling During response actions, the National Oceanic Atmospheric Administration (NOAA) requested that UPRR deploy diffusion bag samplers in the Columbia River near the WWTP outfall. Based on several teleconferences with NOAA, DEQ, and CH2M, it was decided to use a third-party contractor to complete the sampling effort. Oregon State University (OSU) was selected to develop a SAP, deploy the sampling devices, analyze the data, and develop a final report of findings. The OSU SAP and final report are included as Appendix C. OSU deployed manufactured low-density polyethylene PSDs with performance reference compound infusion at six locations in the Columbia River (Figure 3-1). Two locations were significantly upstream of the WWTP outfall to prevent wind-driven sampler contamination (labeled East 1 and East 2 on Figure 3-1). Two locations were located at the WWTP outfall (labeled Center 1 and Center 2), and two samplers located downstream of the WWTP outfall (labeled West 1 and West 2 on Figure 3-1). The PSDs were analyzed for 62 PAHs per OSU standard operating procedures.

3.1.3 Surface Water Analytical Results All Columbia River surface water grab samples were analyzed for VOCs, TPH-Gx, and PAHs. Surface water samples collected from June 5 to 12, 2016, were also analyzed for PIANO. PIANO (named for compounds, Paraffin, Isoparaffin, Aromatic, Napthene and Olefin) is an analytical tool for fingerprinting light-end refined products, such as gasoline and jet fuel. TPH diesel range (Dx) and oil range (O) were added to the analyte list starting on June 15. The most recent analytical results from the Columbia River surface water sampling (September 7, 2016) are shown in Table 3-1. Previous Columbia River sampling results are presented in Appendix D. The complete analytical data packages are presented in Appendix E. Most sampling results for VOCs and PAHs were not detected above the laboratory method detection limit (MDL) in Columbia River surface water samples (upstream, downstream, and the outfall/source), though some detections occurred at each location over the course of the sampling duration. TPH-Gx was not detected in any samples, with the exception of one sample from the outfall/source collected June 17. TPH-Dx was detected periodically at each sample location, while TPH-O was detected in only two samples collected at the outfall/source location on June 17 and 20. A majority of the analytes in the PIANO analysis were not detected, with a few constituents (n-dodecane, benzene, toluene, n-hexylbenzene, and naphthalene) detected in each location. Surface water samples located upstream and downstream of the WWTP effluent line manhole in Rock Creek were collected starting on June 10 and analyzed for VOCs, PAHs, and TPH-Gx. PIANO analysis was only performed on June 10. TPH-Dx and TPH-O were added to the analyte list on June 15. Note, water samples in Rock Creek near the manhole are only sampled when Columbia River levels were high enough to back up into the creek, otherwise no water was present for sampling. The recent analytical results from Rock Creek (September 7, 2016) are shown in Table 3-1. Previous Rock Creek sampling results are presented in Appendix D. The complete analytical packages are presented in Appendix E. No VOC constituents were detected in the Rock Creek samples, with the exception of one VOC (1,2‐dichloroethane) in one upstream

3-2 EN1011161111PDX SECTION 3 sample (September 7) below the reporting limit, and therefore reported as an estimated value. Most sampling results for PAHs were non-detect in the Rock Creek samples (upstream and downstream locations) with some detections occurring at each location. TPH-Gx and TPH-O were not detected in any Rock Creek surface water samples. TPH-Dx was detected periodically at both sample locations, but all detections were below the reporting limit, and therefore estimated. A majority of the sample results from the PIANO analysis were not detected with a few constituents detected at both locations. The OSU PSD sampling results are presented in the final OSU sampling report presented in Appendix C. Analytical results from the grab sampling and the OSU PSD sample results have been tabulated and are presented in Appendix D. 3.2 Sediment Sampling Sediment sampling was conducted in both the Columbia River and Rock Creek. Sediment samples from the Columbia River were collected on June 10 and 14 and sediment samples from Rock Creek were collected on June 10. This section discusses the sediment sampling approach and the laboratory results.

3.2.1 Sediment Sampling Approach Sediment samples were collected from two locations in the Columbia River and two locations in Rock Creek on June 10, and from six locations in the Columbia River on June 14. The locations are shown on Figure 3-2. The two locations sampled from the Columbia River on June 10 were near the WWTP outfall (SED-CR-OF) and from a background location (SED-CR-BCH). The two sediment samples collected from Rock Creek on June 10 were located approximately 40 feet upstream (SED-RC-UP) and 40 feet downstream (SED-RC-DN) of the WWTP manhole. The six locations sampled from the Columbia River on June 14 were collected from two transects (near shore [NS] and offshore [OS]) with an East, Central, and West sample.

3.2.2 Sediment Analytical Results The Columbia River sediment samples were analyzed for TPH-Gx, TPH-Dx, PAHs, and VOCs, with the exception of the SED-CR-BCH and SED-CR-OF samples which were not analyzed for VOCs. The analytical results are shown in Table 3-2. The complete analytical data packages are presented in Appendix E. A majority of VOC sample results were non-detect with single detections below the reporting limit of three different VOCs all at different locations. Most samples had detections of PAH constituents with the highest concentrations occurring in the samples collected near the WWTP outfall. The Rock Creek sediment samples were analyzed for TPH-Gx, TPH-Dx, and PAHs. The analytical results are shown in Table 3-3. The complete analytical data packages are presented in Appendix E. The two samples had detections of PAH constituents. Both locations were non-detect for TPH-Gx. TPH-O was detected at both locations and TPH-Dx was detected in the downstream location. 3.3 Groundwater Sampling Two 4-inch diameter polyvinyl chloride (PVC) monitoring wells (EW-1 and EW-2) and four 2-inch diameter PVC monitoring wells (MW-1 to MW-4) were installed from June 13 through 17, 2016. Four additional 2-inch diameter PVC monitoring wells (MW-5 to MW-8) were installed from July 28 through 30, 2016. The locations of the wells are shown on Figure 1-2. The two 4-inch diameter extraction wells were installed using an air rotary drill rig at the derailment location (source area) on the south side of the railroad tracks. The two extraction wells were initially installed to remove contaminated groundwater, but hydrogeological conditions were not favorable for this type of

EN1011161111PDX 3-3 SECTION 3 – INCIDENT COMMAND SYSTEM SAMPLING

remedial action. As such, these wells serve as monitoring wells. Each well was drilled to approximately 36 to 39 feet below ground surface (bgs). Extraction well EW-1 is screened from 20 to 35 feet bgs and extraction well EW-2 is screened from 15 to 35 feet bgs. The eight 2-inch diameter monitoring wells were installed on the north side of the railroad tracks between the Columbia River and the tracks. Monitoring wells MW-1 through MW-4 were installed using a track-mounted sonic drill rig and monitoring wells MW-5 to MW-8 were installed using an air rotary drill rig. Boring logs and well completion details for these wells are included in Appendix F.

3.3.1 Groundwater Sampling Approach Groundwater samples were collected from extraction wells EW-1, EW-2, and monitoring wells MW-1 through MW-4 at weekly intervals from June 24 through September 9, 2016. Monitoring wells MW-5 to MW-8 were first sampled on August 3, and added to the weekly sampling events thereafter. Sampling was conducted using a low flow sampling method. The water level of the well is initially gauged and recorded. The well is then purged at a rate of approximately 0.2 to 0.5 liters per minute. During purging, water quality parameters (temperature, specific conductance, pH, and oxygen reduction potential [ORP]) are measured periodically (3 to 5 minutes) until the parameters are stable. Samples are then collected and analyzed as discussed below.

3.3.2 Groundwater Analytical Results Each groundwater sample was analyzed for TPH-Gx, TPH-Dx, PAHs, and VOCs. Natural attenuation parameters (nitrate, nitrite, sulfate, alkalinity, and methane) have also been analyzed for select groundwater monitoring events. The sample results from the most recent sampling (September 8 and 9, 2016) are presented in Table 3-4. Additional groundwater sampling data is presented in Appendix G. The complete analytical data packages are presented in Appendix E. Monitoring wells MW-1 to MW-3 and MW-5 to MW-8 each have had relatively low detections of VOCs (benzene up to 0.89 micrograms per liter [µg/L]), PAHs, and TPH-Dx and TPH-Gx. The extractions wells have had higher detections of VOCs (benzene up to 280 µg/L), PAHs, TPH-Dx and TPH-Gx (up to 2.2 milligrams per liter [mg/L]). MW-4 had the highest concentration of VOCs (benzene up to 1,800 µg/L), PAHs, and TPH-Dx and TPH-Gx (up to 9.9 mg/L). Benzene levels have dropped over time at MW-4 (610 µg/L in the sample collected on September 8). 3.4 Soil Sampling Soil excavation began on June 9, 2016 in the area of the tank car fire to determine horizontal and vertical extent of contamination. A transect system was set up to document the excavation limits and map soil confirmation sample locations as described in the incident command sampling plan. A total of 2,960 tons of impacted soil were excavated and disposed of at the Wasco County Landfill. The excavated area is shown on Figure 1-2. DEQ personnel were onsite to visually inspect impacted soil and direct excavation activities. Per the incident command sampling plan, the excavation of soil was driven by visual observation, hydrocarbon odor, and headspace readings using a photo-ionization detector (PID). In addition, CTEH was onsite during all excavation activities to monitor breathing space air. Confirmation soil samples were collected from the initial source area excavation at the site from June 9 to 11, 2016. Samples were collected in transect locations from both the side walls and the floor of the excavation with depths ranging from 3 to 22 feet bgs. Based on the analytical data from the June 9 to 11 sampling, additional excavation was conducted in locations that exceeded DEQ risk-based screening levels and additional confirmation samples were collected on June 21. The area was backfilled after sample collection. All soil samples were analyzed for TPH-Gx, TPH-Dx, PAHs, and VOCs. The locations of the confirmation soil samples collected are presented on Figure 3-3.

3-4 EN1011161111PDX SECTION 3

3.4.1 Initial Excavation and Confirmation Soil Samples A total of 38 samples were collected and analyzed for TPH-Gx, TPH-Dx, PAHs, and VOCs from the initial source area excavation on June 9 through 11, 2016. The complete analytical data packages are presented in Appendix E. Analytical results indicate soil impacts were widespread for select VOCs, PAHs, and TPH-Gx and TPH-Dx. Where analytical data indicated exceedance of DEQ risk-based screening additional excavation was performed. The analytical results for the 13 locations where additional soil was removed are presented in Table 3-5. Two soil samples were collected from excavated soils, and were used to characterize and profile the impacted soil for disposal. One soil sample was collected from offsite to characterize the material that was used to fill the excavated area. The analytical results are presented in Table 3-9. The complete analytical data packages are presented in Appendix E.

3.4.2 Additional Soil Removal and Confirmation Sample Collection Additional soil excavation was completed on June 21 in select areas of the excavation where analytical results showed impacted soil remained within the original excavation footprint. Based on these results, approximately 400 tons of additional soil was excavated and transported to Wasco County Landfill. A total of 11 additional confirmation soil samples were collected and analyzed for PAHs, TPH-Gx, and TPH-Dx. Analytical results for these samples are presented in Table 3-6 along with selected samples from June 9 through 11, where samples are indicative of soil concentrations left in place. The complete analytical data packages are presented in Appendix E. All VOC constituents, TPH-Gx, and TPH-Dx from soil left in place were non-detect with the exception of TPH-Gx in one soil sample (1+75 SW) collected from 10 feet bgs on the sidewall of the excavation, and TPH-Dx in one soil sample in (1+50) collected from 6 feet bgs on the sidewall of the excavation. Selected PAH constituents were detected in each confirmation sample with the exception of three samples: 2+00 SF (floor), 2+50 DF (Deep Floor) and 300 ST (floor). The highest concentrations occurred along transects 0+75, 1+50, 2+25, and 2+50. No additional excavation was performed following the June 21 confirmation sampling event. 3.5 Other Response Action Sampling Additional soil samples were collected during response actions that where not proposed in the incident command sampling plan. This section summarizes samples collected by potholing near the WWTP manhole closest to the Columbia River and track confirmation sampling.

3.5.1 Pothole Soil Sampling Near Manhole Four potholes (Pothole 1-4) were advanced using a vacuum truck (vac truck) neat the WWTP manhole closest to the Columbia River (Figure 3-4). The potholes were terminated at 3 feet bgs. A total of 4 soil samples were collected from the four potholes surrounding the most downgradient WWTP manhole. These samples were collected while the WWTP was not in operation and the effluent pipe was plugged both upstream and downstream of the manhole. The potholing and sampling was completed after a sheen was observed in the manhole. Samples were analyzed for VOCs, PAHs, TPH-Gx, and TPH-Dx. The analytical results are presented in Table 3-7. The complete analytical data packages are presented in Appendix E. Following pothole completion to depth and soil sample collection at Pothole-2, a sheen was observed in the bottom of the hole. The vac truck was used to expand and deepen the potholing in this area to remove additional material. A confirmation soil sample (Pothole-3) was collected at 5 feet bgs, approximately 2 feet deeper than the Pothole-2 sample location, following additional soil removal.

EN1011161111PDX 3-5 SECTION 3 – INCIDENT COMMAND SYSTEM SAMPLING 3.5.2 Mainline Track Confirmation Soil Sampling A total of 11 samples were collected from excavations associated with track removal efforts (Figure 3-4). Approximately 150 feet of mainline track was damaged during the derailment. Soil confirmation soil samples were collected following removal of soil where visually impacted soil was observed along the track bed. In addition, headspace soil samples were collected in plastic bags and recorded with a PID at the 11 sampling locations. The track ballast was removed and impacted shallow soil was excavated and placed in a soil pile near the WWTP (see Table 3-5 for analytical results). The excavation was advanced to approximately 5 to 7 feet bgs, depending on visual impact. A fine sandy silt was present at 5 feet bgs the extended to excavation limits at 7 feet bgs. Confirmation soil samples were collected from the floor of the excavation and sidewalls. Samples were analyzed for PAHs, TPH-Gx, and TPH-Dx. The analytical results are presented in Table 3-8. The complete analytical data packages are presented in Appendix E. Based on PID readings of 10-25 parts per million (ppm) from headspace at locations Track 5 FL and Track 8 Floor, additional soil removal was completed at these locations. The excavation was deepened from 5 to 7 feet and additional confirmation soil samples (Track 6 North Wall and Track 9 Floor) were collected. PID readings at this 7 foot depth were not detected. Based on the analytical data results, impacted soil detected at 5 feet at Track 5 and Track 8 Floor were removed during over-excavation to 7 feet bgs in these areas.

3-6 EN1011161111PDX SECTION 4 4 Biosparge Treatment System

Following completion of the emergency response actions, remedial actions were implemented at the site. Based on dissolved-phase petroleum hydrocarbons detected in groundwater monitoring wells and extraction wells, benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds are the constituents of concern. To address these petroleum constituents, biosparge treatment system was designed by CH2M specifically targeting the high concentrations of these constituents near MW-4. The biosparge treatment system consists of vertical biosparge wells through which air is injected into the groundwater. Oxygen delivery stimulates the growth of microbes that consume petroleum hydrocarbons, thereby reducing concentrations of these constituents in groundwater. 4.1 Treatment System Design The biosparge treatment system consists of an air injection system (AIS), air distribution piping, biosparge wells, and the network of monitoring wells discussed in Section 3-3. The layout of the system is shown in Figure 4-1. The AIS, located within the fenced area of the WWTP, provides pressurized air to inject into the subsurface and consists of a control panel, rotary claw pump (blower), a variable frequency drive (VFD) (range of 0 to 60 hertz [Hz]), an air receiver and filter, a heat exchanger and fan, and a manifold. The system is equipped with a control panel with built-in alarms for high temperature and high pressure that automatically shut down the system. The temperature of the control panel enclosure and the AIS are displayed on the front of the control panel. The blower discharge has a mechanical pressure reducing valve that opens the discharge to atmosphere in the event of high system pressure. The blower discharge also has a pressure and temperature gauge. The air then travels through the heat exchanger and fan to the manifold. The manifold has the ability to connect up to four discharge legs. Currently, the manifold is connected to two legs. Each leg of the manifold has a solenoid valve to control on-off cycles, a gate valve to control flow, a flow meter, and a pressure gage. The compressed air from the system is conveyed through these two legs via buried underground high-density polyethylene piping. The piping travels north underneath the railroad to the five biosparge wells (BS-1 to BS-5). One leg of the piping is connected to BS-1 and BS-2 and the other leg of the piping is connected to BS-3, BS-4, and BS-5. The five wells inject the compressed air into the treatment zone. Each of the five wellheads are equipped with a pressure gauge and a flow control valve. The five 2-inch biosparge wells are screened to 25 to 28 feet bgs, approximately 20 feet below the water table. The wells are spaced approximately 20 to 25 feet apart. 4.2 Startup Baseline values including water levels, water quality parameters, soil gas parameters, and ambient VOC readings were collected prior to treatment system startup. Water quality parameters consisted of dissolved oxygen, pH, ORP, specific conductance, and temperature were recorded at each well location. A baseline soil gas survey was conducted at wells MW-4 to MW-6. Soil gas readings include methane, carbon dioxide, and oxygen. Note, MW-7 and MW-8 were not surveyed for soil gas as water levels in the wells were higher than then screened interval. Ambient VOC air quality readings were measured in the area of the biosparge wells and monitoring wells (MW-4 to MW-8). Testing and startup of the system began on August 18, 2016, with the system operating at a speed of 40 Hz and both legs of the manifold system open. On August 19, 2016 the system was operating at maximum speed of 60 Hz. The two legs of the manifold were initially opened, followed by manually pulsing the wells (e.g., closing one leg and opening the other for a period of time and then switching). Startup monitoring and

EN1011161111PDX 4-1

SECTION 4 – BIOSPARGE TREATMENT SYSTEM

system optimization was completed on August 23, 2016. The system was programmed to run from 8 am to 8 pm (due to nuisance noise considerations) and pulsing flow from one leg to the other every 1.5 hours. Water levels and water qualities values were periodically recorded throughout startup procedures to assess system performance. 4.3 Operation Monitoring The following data will be manually collected from the system: • System temperature and pressure • BS-1 and BS-2 – pressure and flow rate • BS-3, BS-4, and BS-5 – pressure and flow rate • Speed of blower VFD • Temperature of enclosure and AIS • Sparge well pressures (BS-1 to BS-5) This data will be collected on the same schedule as other sampling conducted at the site (groundwater and surface water sampling, and soil gas surveying). The frequency of operational data collection may be revised to meet operational objectives.

4-2 EN1011161111PDX SECTION 5 5 Future Site Actions

Future site actions will consist of surface water and groundwater sampling, soil gas surveying, and biosparge system operations. Future data collection will be summarized in technical memoranda or sampling reports and submitted to DEQ. The monitoring frequency and analyte list will be adjusted based on the sampling results, water quality parameters, and biosparge operations. These are discussed in the following subsections. 5.1 Surface Water Sampling at Rock Creek and Wetland Surface water samples will be collected from Rock Creek when the creek begins to flow. In addition, surface water samples will be collected at the wetland in the City of Mosier Park, north of the track, standing water has been historically observed during winter/spring seasons. Surface water samples will be analyzed for VOCs, PAHs, and TPH-Gx and TPH-Dx. 5.2 Groundwater Sampling Groundwater sampling from each of the 10 monitoring wells (EW-1, EW-2, and MW-1 to MW-8) will be sampled for VOCs, PAHs, and TPH-Gx and TPH-Dx along with natural attenuation parameters (nitrite, nitrate, sulfate, alkalinity, methane, dissolved ferrous iron, and dissolved carbon dioxide) on a monthly basis. 5.3 Soil Gas Surveying Soil gas surveying will be conducted at wells MW-4 to MW-8 when groundwater sampling is performed. Water levels will be gauged in each well prior to surveying to determine if water levels are below the screened interval of the well. If the water level is above the screened interval, the soil gas surveying will not be conducted at the well as purged gas from the well would not be connected to the subsurface. Each well will be analyzed for methane, oxygen, and carbon dioxide. 5.4 Biosparge Operations At the time this site assessment report was drafted, a total of eight additional biosparge wells were installed at the site and air delivery was connected and operational. Three additional biosparge wells were installed near MW-4 and five biosparge wells were installed in the source area near extraction wells EW-1 and EW-2. The additional biosparge wells were installed to enhance dissolved oxygen levels at these locations. Based on future sampling results the biosparge treatment system will be continually evaluated to determine if additional future actions need to be taken, which may include running the system longer, running it at a higher speed, or expanding/moving the biosparge well network to improve performance of the system and meet the site objectives. 5.5 Site Restoration Site restoration activities are currently being implemented. The site restoration includes fire-damaged tree removal, beach repair, installation of a temporary fence and path, plantings, and other restoration objectives to return the site to its original condition.

EN1011161111PDX 5-1

Tables

Table 3-1. Columbia River and Rock Creek Surface Water Sample Results (September 7, 2016) Union Pacific Railroad Company Mosier Release Site Assessment Report Columbia River Rock Creek Sample ID Upstream-090716 Downstream-090716 Source-090716 RC-UP-090716 RC-DN090716 Sample Date 9/7/16 15:10 9/7/16 15:25 9/7/16 15:55 9/7/16 15:35 9/7/16 15:45 Volatile Organic Compounds (µg/L) 1,1,1,2-Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1-Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2-Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2-Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1-Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1-Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1-Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3-Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3-Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3-Trimethylbenzene 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4-Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4-Trimethylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2-Dibromo-3-Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2-Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2-Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2-Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 J 0.16 U 1,2-Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5-Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3-Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3-Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4-Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2-Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2-Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4-Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4-Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis-1,2-Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis-1,3-Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Methyl tert-butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U Page 1 of 2 Table 3-1. Columbia River and Rock Creek Surface Water Sample Results (September 7, 2016) Union Pacific Railroad Company Mosier Release Site Assessment Report Columbia River Rock Creek Sample ID Upstream-090716 Downstream-090716 Source-090716 RC-UP-090716 RC-DN090716 Sample Date 9/7/16 15:10 9/7/16 15:25 9/7/16 15:55 9/7/16 15:35 9/7/16 15:45 m-Xylene & p-Xylene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Naphthalene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U n-Butylbenzene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U N-Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U o-Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec-Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t-Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U trans-1,2-Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U trans-1,3-Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 0.006 U 0.006 U 0.006 U 0.0061 U 0.006 U 2-Methylnaphthalene 0.009 U 0.0091 U 0.009 U 0.0091 U 0.009 U Acenaphthene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[a]anthracene 0.007 J 0.0054 J 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.008 U 0.0081 U 0.008 U 0.0081 U 0.008 U Benzo[g,h,i]perylene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.009 U 0.0091 U 0.009 U 0.0091 U 0.009 U Chrysene 0.006 U 0.006 U 0.006 U 0.0061 U 0.006 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.0043 J 0.002 U 0.002 U 0.0085 J 0.0071 J Fluorene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3-cd]pyrene 0.007 U 0.007 U 0.007 U 0.0071 U 0.007 U Naphthalene 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 0.0075 J 0.0045 J 0.0085 J 0.013 J 0.0099 J Pyrene 0.0041 J 0.004 U 0.004 U 0.0046 J 0.0047 J NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10-C24) 0.11 U 0.11 U 0.11 U 0.019 U 0.11 U Motor Oil (>C24-C36) 0.029 U 0.03 U 0.029 U 0.03 U 0.03 U Notes: NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Results shown in bold denote detected concentrations. Qualifiers µg/L = micrograms per Liter J - Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is mg/L = milligrams per Liter U - Analyte was not detected above the method detection limit (MDL).

Page 2 of 2 Table 3-2. Columbia River Sediment Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID SEDCRBCH61016 SEDCRBCH61016FD SEDCROF61016 CR-OS-East CR-OS-Central CR-OS-West CR-NS-East CR-NS-Central CR-NS-West Sample Date 6/10/16 11:35 6/10/16 11:40 6/10/16 11:50 6/14/16 10:05 6/14/16 9:30 6/14/16 10:30 6/14/16 14:55 6/14/16 13:50 6/14/16 14:30 Volatile Organic Compounds (µg/kg) 1,1,1,2-Tetrachloroethane ------6.6 UJ 5.3 UJ 7.6 UJ 6.1 UJ 4.1 UJ 4.1 UJ 1,1,1-Trichloroethane ------9.7 UJ 7.9 UJ 11 UJ 9 UJ 6 UJ 6.1 UJ 1,1,2,2-Tetrachloroethane ------4 UJ 3.2 UJ 4.6 UJ 3.7 UJ 2.5 UJ 2.5 UJ 1,1,2-Trichloroethane ------4.8 UJ 3.9 UJ 5.6 UJ 4.5 UJ 3 UJ 3 UJ 1,1-Dichloroethane ------7.3 UJ 5.9 UJ 8.4 UJ 6.7 UJ 4.5 UJ 4.6 UJ 1,1-Dichloroethene ------8.5 UJ 6.9 UJ 9.8 UJ 7.9 UJ 5.2 UJ 5.3 UJ 1,1-Dichloropropene ------9.2 UJ 7.5 UJ 11 UJ 8.5 UJ 5.7 UJ 5.8 UJ 1,2,3-Trichlorobenzene ------25 UJ 20 UJ 29 UJ 23 UJ 15 UJ 16 UJ 1,2,3-Trichloropropane ------20 UJ 16 UJ 23 UJ 18 UJ 12 UJ 13 UJ 1,2,3-Trimethylbenzene ------14 UJ 11 UJ 16 UJ 12 UJ 8.3 UJ 8.5 UJ 1,2,4-Trichlorobenzene ------27 UJ 22 UJ 31 UJ 25 UJ 16 UJ 17 UJ 1,2,4-Trimethylbenzene ------69 U 56 U 80 U 64 U 43 U 44 U 1,2-Dibromo-3-Chloropropane ------12 UJ 10 UJ 14 UJ 12 UJ 7.7 UJ 7.8 UJ 1,2-Dibromoethane ------5.9 UJ 4.8 UJ 6.8 UJ 5.4 UJ 3.6 UJ 3.7 UJ 1,2-Dichlorobenzene ------7.8 UJ 6.3 UJ 9 UJ 7.2 UJ 4.8 UJ 4.9 UJ 1,2-Dichloroethane ------5.7 UJ 4.6 UJ 6.6 UJ 5.3 UJ 3.5 UJ 3.6 UJ 1,2-Dichloropropane ------4.2 UJ 3.4 UJ 4.8 UJ 3.8 UJ 2.6 UJ 2.6 UJ 1,3,5-Trimethylbenzene ------13 UJ 11 UJ 15 UJ 12 UJ 8.1 UJ 8.3 UJ 1,3-Dichlorobenzene ------10 UJ 8.3 UJ 12 UJ 9.5 UJ 6.3 UJ 6.4 UJ 1,3-Dichloropropane ------9.5 UJ 7.7 UJ 11 UJ 8.8 UJ 5.9 UJ 6 UJ 1,4-Dichlorobenzene ------19 UJ 15 UJ 22 UJ 17 UJ 12 UJ 12 UJ 2,2-Dichloropropane ------21 UJ 17 UJ 24 UJ 19 UJ 13 UJ 13 UJ 2-Chlorotoluene ------5.9 UJ 4.8 UJ 6.8 UJ 5.4 UJ 3.6 UJ 3.7 UJ 4-Chlorotoluene ------5.2 UJ 4.2 UJ 6 UJ 4.8 UJ 3.2 UJ 3.3 UJ 4-Isopropyltoluene ------14 UJ 11 UJ 23 J 12 UJ 8.3 UJ 8.5 UJ Benzene ------3.6 UJ 3 UJ 4.2 UJ 3.4 UJ 2.2 UJ 2.3 UJ Bromobenzene ------4.2 UJ 3.4 UJ 4.8 UJ 3.8 UJ 2.6 UJ 2.6 UJ Bromochloromethane ------21 UJ 17 UJ 25 UJ 20 UJ 13 UJ 13 UJ Bromodichloromethane ------6.4 UJ 5.2 UJ 7.4 UJ 5.9 UJ 4 UJ 4 UJ Bromoform ------46 UJ 37 UJ 53 UJ 42 UJ 28 UJ 29 UJ Bromomethane ------23 UJ 19 UJ 27 UJ 21 UJ 14 UJ 15 UJ Carbon tetrachloride ------6.6 UJ 5.3 UJ 7.6 UJ 6.1 UJ 4.1 UJ 4.1 UJ Chlorobenzene ------17 UJ 14 UJ 20 UJ 16 UJ 10 UJ 11 UJ Chloroethane ------28 UJ 22 UJ 32 UJ 25 UJ 17 UJ 17 UJ Chloroform ------7.3 UJ 5.9 UJ 8.4 UJ 6.7 UJ 4.5 UJ 4.6 UJ Chloromethane ------17 UJ 14 UJ 20 UJ 16 UJ 11 UJ 11 UJ cis-1,2-Dichloroethene ------8.5 UJ 6.9 UJ 9.8 UJ 7.9 UJ 5.2 UJ 5.3 UJ cis-1,3-Dichloropropene ------3.1 UJ 2.5 UJ 3.6 UJ 2.9 UJ 1.9 UJ 2 UJ Dibromochloromethane ------4.8 UJ 3.9 UJ 5.6 UJ 4.5 UJ 3 UJ 3 UJ Dibromomethane ------13 UJ 10 UJ 15 UJ 12 UJ 7.9 UJ 8.1 UJ Dichlorodifluoromethane ------79 UJ 65 UJ 92 UJ 74 UJ 49 UJ 50 UJ Ethylbenzene ------12 UJ 9.4 UJ 13 UJ 11 UJ 7.2 UJ 7.3 UJ Hexachlorobutadiene ------31 UJ 25 UJ 36 UJ 29 UJ 19 UJ 20 UJ Isopropylbenzene ------15 UJ 12 UJ 17 UJ 14 UJ 9.2 UJ 9.4 UJ Methyl tert-butyl ether ------10 UJ 8.4 UJ 12 UJ 9.6 UJ 6.4 UJ 6.5 UJ

Page 1 of 2 Table 3-2. Columbia River Sediment Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID SEDCRBCH61016 SEDCRBCH61016FD SEDCROF61016 CR-OS-East CR-OS-Central CR-OS-West CR-NS-East CR-NS-Central CR-NS-West Sample Date 6/10/16 11:35 6/10/16 11:40 6/10/16 11:50 6/14/16 10:05 6/14/16 9:30 6/14/16 10:30 6/14/16 14:55 6/14/16 13:50 6/14/16 14:30 Volatile Organic Compounds (µg/kg) Methylene Chloride ------12 UJ 9.6 UJ 14 UJ 11 UJ 7.3 UJ 7.4 UJ m-Xylene & p-Xylene ------66 UJ 54 UJ 77 UJ 62 UJ 41 UJ 42 UJ Naphthalene ------22 UJ 18 UJ 26 UJ 20 UJ 14 UJ 14 UJ n-Butylbenzene ------20 UJ 17 UJ 24 UJ 19 UJ 13 UJ 13 UJ N-Propylbenzene ------12 UJ 9.6 UJ 14 UJ 11 UJ 7.3 UJ 7.4 UJ o-Xylene ------5.7 J 4.2 UJ 6 UJ 4.8 UJ 3.2 UJ 3.3 UJ sec-Butylbenzene ------14 UJ 11 UJ 16 UJ 13 UJ 8.7 UJ 8.8 UJ Styrene ------11 UJ 8.6 UJ 12 UJ 9.8 UJ 6.5 UJ 6.6 UJ t-Butylbenzene ------13 UJ 11 UJ 15 UJ 12 UJ 8.2 UJ 8.4 UJ Tetrachloroethene ------9.2 UJ 7.5 UJ 11 UJ 8.5 UJ 5.7 UJ 5.8 UJ Toluene ------12 UJ 9.6 UJ 14 UJ 33 J 7.3 UJ 7.4 UJ trans-1,2-Dichloroethene ------25 UJ 21 UJ 29 UJ 23 UJ 16 UJ 16 UJ trans-1,3-Dichloropropene ------12 UJ 9.8 UJ 14 UJ 11 UJ 7.5 UJ 7.6 UJ Trichloroethene ------5.4 UJ 4.4 UJ 6.2 UJ 5 UJ 3.3 UJ 3.4 UJ Trichlorofluoromethane ------65 UJ 53 UJ 75 UJ 60 UJ 40 UJ 41 UJ Vinyl chloride ------12 UJ 10 UJ 14 UJ 11 UJ 7.6 UJ 7.7 UJ Semi-volatile Organic Compounds (µg/kg) 1-Methylnaphthalene 4.4 J 11 3.1 J 0.68 U 0.8 U 2.7 J 0.89 U 0.64 U 0.63 U 2-Methylnaphthalene 5 J 14 2.9 J 0.49 U 0.57 U 2.7 J 0.63 U 1.7 J 0.45 U Acenaphthene 0.91 U 0.9 U 2.8 J 0.65 U 0.76 U 0.92 U 0.85 U 1.5 J 0.6 U Acenaphthylene 1.1 J 2.2 J 1.9 J 0.54 U 0.63 U 3.4 J 0.71 U 0.5 U 0.5 U Anthracene 2.1 J 4.4 J 52 0.65 U 0.76 U 2.1 J 0.85 U 1.4 J 0.6 U Benzo[a]anthracene 8.9 8.4 520 0.82 U 0.96 U 1.9 J 1.1 U 0.77 U 0.76 U Benzo[a]pyrene 11 5 J 500 0.43 U 0.51 U 0.61 U 0.56 U 0.4 U 0.4 U Benzo[b]fluoranthene 18 12 630 0.64 U 0.75 U 2.5 J 0.83 U 1.5 J 0.59 U Benzo[g,h,i]perylene 6 J 2.8 J 150 0.54 U 0.63 U 1.7 J 0.71 U 0.5 U 0.5 U Benzo[k]fluoranthene 5.9 J 3.9 J 240 0.65 U 0.76 U 0.92 U 0.85 U 0.71 J 0.6 U Chrysene 13 14 690 1.6 U 1.9 U 3.6 J 2.1 U 1.5 U 1.5 U Dibenz(a,h)anthracene 1.1 U 1.1 U 68 0.78 U 0.91 U 1.1 U 1 U 0.73 U 0.72 U Fluoranthene 18 J 36 J 460 1.5 U 3.5 J 10 4.8 J 2.7 J 1.4 U Fluorene 1.6 J 1.9 J 6.4 0.54 U 0.63 U 0.76 U 0.71 U 2.3 J 0.5 U Indeno[1,2,3-cd]pyrene 8.8 3.7 J 230 0.65 U 0.76 U 1.6 J 0.85 U 0.61 U 0.6 U Naphthalene 7.1 J 9.9 2.9 J 0.87 U 1 U 12 3 J 1.5 J 0.8 U Phenanthrene 14 18 130 1.2 J 3 J 10 7.1 2.8 J 1.2 J Pyrene 15 J 28 J 490 1 U 2.9 J 8 3.8 J 2.3 J 0.97 U NWTPH (mg/kg) Gasoline 0.93 U 1.2 J 0.63 U 4.7 J 2.0 J 2.8 J 1.1 J 0.51 U 0.54 U #2 Diesel (C10-C24) 28 J 38 J 14 U 16 U 14 J 15 U 15 U 11 U 10 U Motor Oil (>C24-C36) 160 220 58 J 23 J 170 18 J 100 20 J 8.6 U Moisture Content (percent) Percent Moisture 36.7 37.9 21.8 31.3 27.9 36.5 34.2 17.6 4.2 Percent Solids 63.3 62.1 78.2 68.7 72.1 63.5 65.8 82.4 95.8 Notes: NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Results shown in bold denote detected concentrations. Qualifiers "-" = Not analyzed J - Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. µg/kg = microgram(s) per kilogram U - Analyte was not detected above the method detection limit (MDL). mg/kg = milligram(s) per kilogram

Page 2 of 2 Table 3-3. Rock Creek Sediment Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID SEDRCDN61016 SEDRCUP61016 Sample Date 6/10/16 12:30 6/10/16 12:45 Semi-volatile Organic Compounds (µg/kg) 1-Methylnaphthalene 0.89 U 1.1 J 2-Methylnaphthalene 0.64 U 1.5 J Acenaphthene 0.85 U 0.74 U Acenaphthylene 0.71 U 0.62 U Anthracene 0.85 U 0.74 U Benzo[a]anthracene 1.6 J 0.94 U Benzo[a]pyrene 1.5 J 0.82 J Benzo[b]fluoranthene 3.8 J 1.9 J Benzo[g,h,i]perylene 0.71 U 0.62 U Benzo[k]fluoranthene 1.2 J 0.74 U Chrysene 2.4 J 1.9 U Dibenz(a,h)anthracene 1.0 U 0.89 U Fluoranthene 7.6 1.9 J Fluorene 0.71 U 0.62 U Indeno[1,2,3-cd]pyrene 0.85 U 1.4 J Naphthalene 1.1 U 0.99 U Phenanthrene 3.6 J 6.2 U Pyrene 5.3 J 1.5 J NWTPH (mg/kg) Gasoline 0.82 U 0.64 U #2 Diesel (C10-C24) 16 J 13 U Motor Oil (>C24-C36) 84 61 Moisture Content (percent) Percent Moisture 32.6 23.9 Percent Solids 67.4 76.1 Notes: Results shown in bold denote detected concentrations. "-" = Not analyzed µg/kg = microgram(s) per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J - Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U - Analyte was not detected above the method detection limit (MDL).

Page 1 of 1 Table 3-4. Groundwater Sample Results (September 8 and 9, 2016) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1-090916 MW2-090816 MW3 - 090816 MW4 - 090816 MW5 - 090816 MW6 - 090816 MW7 - 090816 MW8 - 090816 EW1-090916 DUP-090916 EW2-090916 Sample Date 9/9/16 13:50 9/8/16 16:00 9/8/16 10:50 9/8/16 11:40 9/8/16 12:25 9/8/16 13:05 9/8/16 14:00 9/8/16 15:20 9/9/16 11:10 9/9/16 10:00 9/9/16 12:40 Volatile Organic Compounds (µg/L) 1,1,1,2-Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1-Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2-Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2-Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1-Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1-Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1-Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3-Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3-Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3-Trimethylbenzene 0.25 U 0.25 U 0.29 J 83 0.25 U 0.25 U 0.25 U 0.25 U 58 55 10 1,2,4-Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4-Trimethylbenzene 3 U 0.34 J 0.76 J 150 0.27 U 0.27 U 0.27 U 0.27 U 56 52 12 1,2-Dibromo-3-Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2-Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2-Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2-Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 J 0.16 U 0.16 J 0.16 U 0.16 U 0.16 J 1,2-Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5-Trimethylbenzene 0.26 U 0.26 J 0.35 J 40 0.26 U 0.26 U 0.26 U 0.26 U 22 21 4.4 1,3-Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3-Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4-Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2-Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2-Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4-Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4-Isopropyltoluene 0.26 U 0.26 U 0.26 U 4.8 0.26 U 0.26 U 0.26 U 0.26 U 1.5 J 1.6 J 0.43 J Benzene 0.42 U 0.42 U 0.42 U 610 0.42 U 0.42 U 0.42 U 0.42 U 210 230 6.6 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis-1,2-Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis-1,3-Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 60 0.21 U 0.21 U 0.21 U 0.21 U 37 35 0.85 J

Page 1 of 3 Table 3-4. Groundwater Sample Results (September 8 and 9, 2016) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1-090916 MW2-090816 MW3 - 090816 MW4 - 090816 MW5 - 090816 MW6 - 090816 MW7 - 090816 MW8 - 090816 EW1-090916 DUP-090916 EW2-090916 Sample Date 9/9/16 13:50 9/8/16 16:00 9/8/16 10:50 9/8/16 11:40 9/8/16 12:25 9/8/16 13:05 9/8/16 14:00 9/8/16 15:20 9/9/16 11:10 9/9/16 10:00 9/9/16 12:40 Hexachlorobutadiene ------Hexachloro-1,3-butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 15 0.3 U 0.3 U 0.3 U 0.3 U 4.8 4.8 0.73 J Isopropyltoluene ------Methyl tert-Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m-Xylene & p-Xylene 0.3 U 0.3 U 0.53 J 230 0.3 U 0.3 U 0.3 U 0.3 U 140 160 9.1 Naphthalene 0.26 U 0.26 U 2 U 17 0.26 U 0.26 U 0.26 U 0.26 U 9.9 9.9 2 U n-Butylbenzene 0.3 U 0.3 U 0.51 J 22 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 7.6 2.5 J n-Propylbenzene 0.13 U 0.13 U 0.13 U 12 0.13 U 0.13 U 0.13 U 0.13 U 3.4 3.1 0.26 J o-Xylene 0.49 U 0.49 U 0.49 U 150 0.49 U 0.49 U 0.49 U 0.49 U 130 150 14 sec-Butylbenzene 0.27 U 0.27 U 0.27 U 4 0.27 U 0.27 U 0.27 U 0.27 U 3 U 3 U 3 U Styrene 0.36 U 0.36 U 0.36 U 0.72 J 0.36 U 0.36 U 0.36 U 0.36 U 1.3 J 1.3 J 0.36 U tert-Butylbenzene 0.27 U 0.27 U 0.27 U 0.51 J 0.27 U 0.27 U 0.27 U 0.27 U 0.42 J 0.34 J 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 J 0.38 J 370 0.18 U 0.18 U 0.18 U 0.18 U 250 270 5.8 Total Xylenes ------trans-1,2-Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans-1,3-Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 0.0062 U 0.0061 U 0.0062 U 13 0.0062 U 0.0061 U 0.0062 U 0.0061 U 2.6 1.8 0.036 2-Methylnaphthalene 0.0094 U 0.0092 U 0.0093 U 8.6 0.0092 U 0.0092 U 0.0093 U 0.0092 U 0.59 0.42 0.0093 U Acenaphthene 0.0021 U 0.002 U 0.0021 U 0.1 0.0021 U 0.002 U 0.0021 U 0.002 U 0.024 0.02 0.0021 U Acenaphthylene 0.0021 U 0.002 U 0.0021 U 0.2 0.0021 U 0.002 U 0.0021 U 0.002 U 0.15 0.11 0.0021 U Anthracene 0.0031 U 0.0031 U 0.0031 U 0.0085 J 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[a]anthracene 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U Benzo[a]pyrene 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[b]fluoranthene 0.0083 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0083 U 0.0082 U 0.0082 U 0.0082 U 0.0083 U Benzo[g,h,i]perylene 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[k]fluoranthene 0.0094 U 0.0092 U 0.0093 U 0.0092 U 0.0092 U 0.0092 U 0.0093 U 0.0092 U 0.0092 U 0.0092 U 0.0093 U Chrysene 0.0062 U 0.0061 U 0.0062 U 0.0062 U 0.0062 U 0.0061 U 0.0062 U 0.0061 U 0.0062 U 0.0061 U 0.0062 U Dibenz(a,h)anthracene 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U Fluoranthene 0.0021 U 0.002 U 0.0021 U 0.0071 J 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U Fluorene 0.0031 U 0.0031 U 0.0031 U 0.39 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.093 0.087 0.0031 U Indeno[1,2,3-cd]pyrene 0.0073 U 0.0071 U 0.0072 U 0.0072 U 0.0072 U 0.0071 U 0.0073 U 0.0071 U 0.0072 U 0.0071 U 0.0072 U Naphthalene 0.014 U 0.013 U 0.013 U 10 0.013 U 0.013 U 0.013 U 0.013 U 3.6 2.6 0.013 U Phenanthrene 0.0074 J 0.0041 U 0.0041 U 0.2 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0085 J 0.0041 U 0.0041 U Pyrene 0.0042 U 0.0041 U 0.0041 U 0.012 J 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U

Page 2 of 3 Table 3-4. Groundwater Sample Results (September 8 and 9, 2016) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1-090916 MW2-090816 MW3 - 090816 MW4 - 090816 MW5 - 090816 MW6 - 090816 MW7 - 090816 MW8 - 090816 EW1-090916 DUP-090916 EW2-090916 Sample Date 9/9/16 13:50 9/8/16 16:00 9/8/16 10:50 9/8/16 11:40 9/8/16 12:25 9/8/16 13:05 9/8/16 14:00 9/8/16 15:20 9/9/16 11:10 9/9/16 10:00 9/9/16 12:40 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.029 J 3.5 0.027 U 0.027 U 0.027 U 0.027 U 2.2 2.2 0.24 #2 Diesel (C10-C24) 0.12 0.033 J 0.069 J 0.53 0.047 J 0.032 J 0.17 0.035 J 0.4 0.54 0.08 J Motor Oil (>C24-C36) 0.058 J 0.03 U 0.18 J 0.035 J 0.05 J 0.03 U 0.043 J 0.03 U 0.079 J 0.087 J 0.03 U Natural Attenuation Parameters (mg/L) Alkalinity ------Methane ------Nitrate as N ------Nitrite as N ------Sulfate ------Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter mg/L = milligram(s) per liter NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J - Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U - Analyte was not detected above the method detection limit (MDL).

Page 3 of 3 Table 3‐5. Initial Confirmation Soil Sample Results (Soil Later Removed) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 0+50 F 0+50 F1 0+50 NW1 1+00 F 1+00 NW1 1+25 F1+25 NW 1+50 F 1+50 NF1 1+50 NW1 1+75 F1 1+75 NF1 2+00 NF1 Type Floor Floor Sidewall Floor Sidewall Floor Sidewall Floor Floor Sidewall Floor Floor Floor Date Sampled 6/9/16 6/11/16 6/11/16 6/10/166/10/16 6/10/16 6/11/16 6/10/16 6/10/16 6/10/16 6/11/16 6/10/16 6/10/16 Volatile Organic Compounds (mg/kg) 1,1,1,2‐Tetrachloroethane 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1,1‐Trichloroethane (TCA) 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,1,2,2‐Tetrachloroethane 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.2 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1,2‐Trichloroethane 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1‐Dichloroethane 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1‐Dichloroethene 0.05 U 0.05 U 0.05 U 1 0.05 U 0.25 1 1 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,1‐Dichloropropene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,2,3‐Trichlorobenzene 0.10 U 0.10 U 0.10 U 2.0 0.10 U 0.5 2.0 2.0 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 1,2,3‐Trichloropropane 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.2 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2,4‐Trichlorolbenzene 0.05 U 0.05 U 0.05 U 1.0 0.05 U 0.3 1.0 1.0 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,2,4‐Trimethylbenzene 0.02 U 2.3 0.8 26.9 0.9 9.5 47.3 23.9 26.0 3.50 U 1.6 2.5 0.02 U 1,2‐Dibromo‐3‐Chloropropane 0.05 U 0.05 U 0.05 U 1.0 0.05 U 0.3 1.0 1.0 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,2‐Dibromoethane (EDB) * 0.005 U 0.005 U 0.005 U 0.1 0.005 U 0.025 0.1 0.1 0.005 U 0.005 U 0.005 U 0.005 U 0.005 U 1,2‐Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.2 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2‐Dichloroethane (EDC) 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2‐Dichloropropane 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,3,5‐Trimethylbenzene 0.02 U 0.5 0.1 5.9 0.2 2.0 9.7 10.9 6.1 0.77 0.3 0.62 0.02 U 1,3‐Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.2 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,3‐Dichloropropane 0.05 U 0.05 U 0.05 U 1 0.05 U 0.25 1 1 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,4‐Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.2 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 2,2‐Dichloropropane 0.05 U 0.05 U 0.05 U 1 0.05 U 0.25 1 1 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 2‐Chlorotoluene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 4‐Chlorotoluene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Benzene 0.02 U 0.06 0.075 1.03 0.18 0.44 1.3 0.79 1.2 0.30 0.046 0.028 0.02 U Bromobenzene 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.2 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Bromodichloromethane 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Bromoform 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.2 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Bromomethane 0.09 U 0.09 U 0.09 U 1.8 0.09 U 0.45 1.8 1.8 0.09 U 0.09 U 0.09 U 0.09 U 0.09 U Carbon tetrachloride 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Chlorobenzene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Chloroethane 0.06 U 0.06 U 0.06 U 1.2 0.06 U 0.3 1.2 1.2 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U Chloroform 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Chloromethane 0.06 U 0.06 U 0.06 U 1.2 0.06 U 0.3 1.2 1.2 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U cis ‐1,2‐Dichloroethene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U cis‐1,3‐Dichloropropene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Dibromochloromethane 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U

Page 1 of 3 Table 3‐5. Initial Confirmation Soil Sample Results (Soil Later Removed) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 0+50 F 0+50 F1 0+50 NW1 1+00 F 1+00 NW1 1+25 F1+25 NW 1+50 F 1+50 NF1 1+50 NW1 1+75 F1 1+75 NF1 2+00 NF1 Type Floor Floor Sidewall Floor Sidewall Floor Sidewall Floor Floor Sidewall Floor Floor Floor Date Sampled 6/9/16 6/11/16 6/11/16 6/10/166/10/16 6/10/16 6/11/16 6/10/16 6/10/16 6/10/16 6/11/16 6/10/16 6/10/16 Dibromomethane 0.04 U 0.04 U 0.04 U 0.8 0.04 U 0.2 0.8 0.8 0.04 U 0.04 U 0.04 U 0.04 U 0.04 U Dichlorodifluoromethane 0.06 U 0.06 U 0.06 U 1.2 0.06 U 0.3 1.2 1.2 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U Ethylbenzene 0.05 U 0.26 0.05 U 2.47 0.087 0.74 3.35 4.19 3.4 0.44 0.067 0.21 0.05 U Hexachloro‐1,3‐butadiene 0.10 U 0.10 U 0.10 U 2.0 0.10 U 0.5 2.0 2.0 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U Isopropylbenzene 0.08 U 0.1 0.08 U 1.4 0.08 U 0.4 2.0 2.5 1.6 0.21 0.08 U 0.13 0.08 U Isopropyltoluene 0.02 U 0.2 0.1 1.7 0.0 0.5 3.1 3.1 1.6 0.19 0.1 0.15 0.02 U Methyl tert‐ Butyl Ether (MTBE) 0.05 U 0.05 U 0.05 U 1 0.05 U 0.25 1 1 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Methylene chloride 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Naphthalenes 0.05 U 0.3 3.5 4.2 0.1 1.5 16.5 9.7 2.5 0.23 0.3 0.31 0.05 U n‐Butylbenzene 0.02 U 0.3 0.2 3.7 0.1 1.2 7.5 7.0 2.9 0.41 0.3 0.31 0.02 U n‐Propylbenzene 0.02 U 0.3 0.1 3.1 0.1 1.0 4.6 6.0 3.4 0.44 0.2 0.28 0.02 U sec‐Butylbenzene 0.02 U 0.1 0.0 1.8 0.1 0.6 3.1 0.4 1.7 0.20 0.1 0.24 0.02 U Styrene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 0.02 U 0.02 U 0.02 U 0.02 U tert‐Butylbenzene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 1.3 0.4 0.4 0.079 0.02 U 0.02 U 0.02 U 0.02 U Tetrachloroethene (PCE) 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Toluene 0.10 U 0.66 0.18 5.49 0.35 1.85 7.91 6.05 8.3 1.4 0.16 0.28 0.10 U Total Xylenes 0.15 U 2.02 0.29 19.9 0.65 6.05 27.7 19.3 23 3.1 0.63 1.53 0.15 U trans ‐1,2‐Dichloroethene 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Trans‐1,3‐Dichloropropene 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Trichloroethene (TCE) 0.03 U 0.03 U 0.03 U 0.6 0.03 U 0.15 0.6 0.6 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Trichlorofluoromethane 0.05 U 0.05 U 0.05 U 1 0.05 U 0.25 1 1 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Vinyl chloride 0.02 U 0.02 U 0.02 U 0.4 0.02 U 0.1 0.4 0.4 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Semi‐volatile Organic Compounds (µg/kg) 1‐Methylnaphthalene 3.2 J 830 J 2,100 13,000 860 3,500 20,000 15,000 16,000 15,000 1,100 400 11 2‐Methylnaphthalene 4 J 950 J 2,900 17,000 1,000 4,200 24,000 19,000 19,000 19,000 1,400 460 11 Acenaphthene 1.6 J 1,000 J 4,400 240 26 J 3.4 U 390 360 180 250 0.6 U 10 0.68 U Acenaphthylene 1.2 J 190 J 730 460 53 130 610 500 320 370 55 17 0.56 U Anthracene 3.8 J 9,900 2,700 3.1 U 100 3.4 U 390 540 0.70 U 310 33 7.3 1.5 J Benzo[a]anthracene 6.9 3,600 J 7,100 3.9 U 94 49 290 180 0.88 U 260 29 9.5 2.2 J Benzo[a]pyrene 7 910 J 5,200 77 66 40 120 82 0.46 U 130 23 2.5 J 0.45 U Benzo[b]fluoranthene 33 1,700 J 8,300 95 210 59 360 100 0.68 U 260 32 9.5 3.2 J Benzo[g,h,i]perylene 19 290 J 2,000 51 140 28 74 49 0.58 U 57 14 1.6 J 0.56 U Benzo[k]fluoranthene 12 730 J 2,600 22 J 45 20 J 78 39 0.70 U 59 11 2.4 J 1.5 J Chrysene 42 4,400 8,500 780 220 250 1,600 810 480.0 930 85 35 3.6 J Dibenz(a,h)anthracene 2.2 J 65 J 480 44 28 J 4.1 U 33 17 J 0.83 U 0.85 U 0.72 U 0.86 U 0.81 U Fluoranthene 22 17,000 18,000 280 290 200 1,100 640 140.0 1200 88 36 8.1 Fluorene 1.7 J 2,300 J 4,500 920 58 250 1,300 910 610.0 890 97 33 0.56 U Indeno[1,2,3‐cd]pyrene 13 360 J 2,200 60 130 33 84 35 0.70 U 65 13 2.7 J 0.68 U Naphthalene 0.86 U 390 J 1,600 3,500 450 830 4,700 4,300 2,900 4100 230 57 7.7 Phenanthrene 14 15,000 13,000 3,200 480 870 5,800 4,500 2,200 3,700 390 99 9.7 Pyrene 15 12,000 17,000 400 210 150 1,100 710 300.0 980 80 36 5.5 J

Page 2 of 3 Table 3‐5. Initial Confirmation Soil Sample Results (Soil Later Removed) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 0+50 F 0+50 F1 0+50 NW1 1+00 F 1+00 NW1 1+25 F1+25 NW 1+50 F 1+50 NF1 1+50 NW1 1+75 F1 1+75 NF1 2+00 NF1 Type Floor Floor Sidewall Floor Sidewall Floor Sidewall Floor Floor Sidewall Floor Floor Floor Date Sampled 6/9/16 6/11/16 6/11/16 6/10/166/10/16 6/10/16 6/11/16 6/10/16 6/10/16 6/10/16 6/11/16 6/10/16 6/10/16 NWTPH (mg/kg) Gasoline 10 U 3,900 156 3,780 94 775 7,330 E 3,300 1,000 E 206 E 203 340 E 10 U Diesel 50 U 2,370 3,140 34,400 2,050 9,300 46,400 83,200 22,600 27,800 2,220 900 50 U Oil 250 U ‐‐‐‐‐‐‐‐‐‐‐‐ NWTPH/VPH ‐ Volatile Petroleum Hydrocarbons (mg/kg) C5‐C6 Aliphatics ‐‐‐‐‐‐‐‐‐‐6U ‐‐ C6‐C8 Aliphatics ‐‐‐‐‐‐‐‐‐‐0.91 J ‐‐ C8‐C10 Aliphatics ‐‐‐‐‐‐‐‐‐‐10 J ‐‐ C8‐C10 Aromatics ‐‐‐‐‐‐‐‐‐‐6.4 J ‐‐ C10‐C12 Aliphatics ‐‐‐‐‐‐‐‐‐‐11 J ‐‐ C10‐C12 Aromatics ‐‐‐‐‐‐‐‐‐‐21 J ‐‐ C12‐C13 Aromatics ‐‐‐‐‐‐‐‐‐‐57 J ‐‐ Total VPH ‐‐‐‐‐‐‐‐‐‐84 J ‐‐ NWTPH/EPH ‐ Extractable Petroleum Hydrocarbons (mg/kg) C8‐C10 Aliphatics ‐‐‐‐‐‐‐‐‐‐6.9 ‐‐ C8‐C10 Aromatics ‐‐‐‐‐‐‐‐‐‐1.1 U ‐‐ C10‐C12 Aliphatics ‐‐‐‐‐‐‐‐‐‐39 J ‐‐ C10‐C12 Aromatics ‐‐‐‐‐‐‐‐‐‐5.7 ‐‐ C12‐C16 Aliphatics ‐‐‐‐‐‐‐‐‐‐180 ‐‐ C12‐C16 Aromatics ‐‐‐‐‐‐‐‐‐‐31 ‐‐ C16‐C21 Aliphatics ‐‐‐‐‐‐‐‐‐‐260 ‐‐ C16‐C21 Aromatics ‐‐‐‐‐‐‐‐‐‐130 ‐‐ C21‐C34 Aliphatics ‐‐‐‐‐‐‐‐‐‐430 ‐‐ C21‐C34 Aromatics ‐‐‐‐‐‐‐‐‐‐200 ‐‐ Moisture Content (percent) Percent Moisture ‐ 10.7 8.7 12.7 22.2 15.5 11.6 8.7 17.6 22.6 9 19.2 14.3 Percent Solids ‐ 89.3 91.3 87.3 77.8 84.5 88.4 91.3 82.4 77.4 91 80.8 85.7 Notes: The soil results in this table represent soil that was subsequently removed. Results shown in bold denote detected concentrations. 1 Detection limits for VOCs identified as laboratory reporting limit and NWTPH‐Gx and NWTPH‐Dx identified as Practical Quantitation Limit. No method detection limit values available. µg/kg = micrograms per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 3 of 3 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 0+00 EW1 0+00 NW1 0+50 SW1 0+50 EW1 0+50 F 0+50 NW 0+75 SW1 0+75 F1 0+75 NW1 1+00 SW1 1+00 F 1+00 NW 1+25 SW1 1+25 F Type Sidewall Sidewall Sidewall Sidewall Floor Sidewall Sidewall Floor Sidewall Sidewall Floor Sidewall Sidewall Floor Depth (ft bgs) 3 3 3 3 4.5 4 4 4 3 5 4 4 5 4 Date Sampled 6/9/16 6/9/16 6/11/16 6/9/16 6/21/16 6/21/16 6/11/16 6/11/16 6/11/16 6/10/16 6/21/16 6/21/16 6/10/16 6/21/16 Volatile Organic Compounds (mg/kg) 1,1,1,2-Tetrachloroethane 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,1,1-Trichloroethane (TCA) 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - 1,1,2,2-Tetrachloroethane 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,1,2-Trichloroethane 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,1-Dichloroethane 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,1-Dichloroethene 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - 1,1-Dichloropropene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - 1,2,3-Trichlorobenzene 0.10 U 0.10 U 0.10 U 0.10 U - - 0.10 U 0.10 U 0.10 U 0.10 U - - 0.10 U - 1,2,3-Trichloropropane 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,2,4-Trichlorolbenzene 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - 1,2,4-Trimethylbenzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - 1,2-Dibromo-3-Chloropropane 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - 1,2-Dibromoethane (EDB) * 0.005 U 0.005 U 0.005 U 0.005 U - - 0.005 U 0.005 U 0.005 U 0.005 U - - 0.005 U - 1,2-Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,2-Dichloroethane (EDC) 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,2-Dichloropropane 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - 1,3,5-Trimethylbenzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - 1,3-Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 1,3-Dichloropropane 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - 1,4-Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - 2,2-Dichloropropane 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - 2-Chlorotoluene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - 4-Chlorotoluene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Benzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Bromobenzene 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - Bromodichloromethane 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Bromoform 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - Bromomethane 0.09 U 0.09 U 0.09 U 0.09 U - - 0.09 U 0.09 U 0.09 U 0.09 U - - 0.09 U - Carbon tetrachloride 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - Chlorobenzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Chloroethane 0.06 U 0.06 U 0.06 U 0.06 U - - 0.06 U 0.06 U 0.06 U 0.06 U - - 0.06 U - Chloroform 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Chloromethane 0.06 U 0.06 U 0.06 U 0.06 U - - 0.06 U 0.06 U 0.06 U 0.06 U - - 0.06 U - cis -1,2-Dichloroethene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - cis-1,3-Dichloropropene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Dibromochloromethane 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - Dibromomethane 0.04 U 0.04 U 0.04 U 0.04 U - - 0.04 U 0.04 U 0.04 U 0.04 U - - 0.04 U - Dichlorodifluoromethane 0.06 U 0.06 U 0.06 U 0.06 U - - 0.06 U 0.06 U 0.06 U 0.06 U - - 0.06 U - Ethylbenzene 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - Hexachloro-1,3-butadiene 0.10 U 0.10 U 0.10 U 0.10 U - - 0.10 U 0.10 U 0.10 U 0.10 U - - 0.10 U - Isopropylbenzene 0.08 U 0.08 U 0.08 U 0.08 U - - 0.08 U 0.08 U 0.08 U 0.08 U - - 0.08 U -

Page 1 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 0+00 EW1 0+00 NW1 0+50 SW1 0+50 EW1 0+50 F 0+50 NW 0+75 SW1 0+75 F1 0+75 NW1 1+00 SW1 1+00 F 1+00 NW 1+25 SW1 1+25 F Type Sidewall Sidewall Sidewall Sidewall Floor Sidewall Sidewall Floor Sidewall Sidewall Floor Sidewall Sidewall Floor Depth (ft bgs) 3 3 3 3 4.5 4 4 4 3 5 4 4 5 4 Date Sampled 6/9/16 6/9/16 6/11/16 6/9/16 6/21/16 6/21/16 6/11/16 6/11/16 6/11/16 6/10/16 6/21/16 6/21/16 6/10/16 6/21/16 Isopropyltoluene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Methyl tert- Butyl Ether (MTBE) 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - Methylene chloride 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Naphthalenes 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - n-Butylbenzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - n-Propylbenzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - sec-Butylbenzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Styrene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - tert-Butylbenzene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Tetrachloroethene (PCE) 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Toluene 0.10 U 0.10 U 0.10 U 0.10 U - - 0.10 U 0.10 U 0.10 U 0.10 U - - 0.10 U - Total Xylenes 0.15 U 0.15 U 0.15 U 0.15 U - - 0.15 U 0.15 U 0.15 U 0.15 U - - 0.15 U - trans -1,2-Dichloroethene 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Trans-1,3-Dichloropropene 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - Trichloroethene (TCE) 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U - - 0.03 U - Trichlorofluoromethane 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U - - 0.05 U - Vinyl chloride 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U - - 0.02 U - Semi-volatile Organic Compounds (µg/kg) 1-Methylnaphthalene 1.7 J 17 75 0.75 J 4.3 J 2.6 J 36 120 470 45 0.72 U 7.7 67 2.4 J 2-Methylnaphthalene 2.5 J 24 82 0.74 J 4.5 J 2.8 J 33 130 680 43 1.5 J 8.4 74 2.7 J Acenaphthene 0.69 U 15 4.7 J 0.65 U 0.62 UJ 0.82 UJ 0.66 U 3.7 U 61 0.63 U 0.68 U 3.0 J 3.0 U 0.68 U Acenaphthylene 0.58 U 9 12 0.54 U 0.51 UJ 0.68 UJ 5.6 13 J 68 6.9 0.57 U 0.59 U 5.6 J 0.56 U Anthracene 0.69 U 11 15 0.65 U 0.62 UJ 0.82 UJ 6.2 19 J 130 6.5 0.68 U 1.7 J 5.2 J 0.68 U Benzo[a]anthracene 0.88 U 13 28 0.82 U 0.78 UJ 1 UJ 11 21 J 120 12 0.86 U 0.9 U 13 J 0.86 U Benzo[a]pyrene 0.46 U 6.8 47 0.43 U 0.41 UJ 0.55 UJ 7.6 7.3 J 59 12 0.45 U 0.47 U 13 J 0.45 U Benzo[b]fluoranthene 0.68 U 19 110 0.64 U 0.61 UJ 0.8 UJ 24 26 J 190 25 0.67 U 0.7 U 33 0.67 U Benzo[g,h,i]perylene 0.58 U 6.6 57 0.54 U 0.51 UJ 0.68 UJ 15 9.2 J 81 17 0.57 U 0.59 U 24 J 0.56 U Benzo[k]fluoranthene 0.69 U 7.2 28 0.65 U 0.62 UJ 0.82 UJ 7.2 8.7 J 66 11 0.68 U 0.71 U 8 J 0.68 U Chrysene 1.7 U 27 83 1.6 U 1.5 UJ 2 UJ 22 31 250 21 1.7 U 1.8 U 32 1.7 U Dibenz(a,h)anthracene 0.83 U 0.86 J 11 0.78 U 0.74 UJ 0.98 UJ 2.5 J 4.5 U 14 J 3.3 J 0.82 U 0.85 U 3.6 U 0.81 U Fluoranthene 1.6 U 61 77 1.5 U 1.4 UJ 1.9 UJ 26 88 520 26 1.6 U 16 30 1.6 U Fluorene 0.58 U 19 9.4 0.54 U 0.51 UJ 0.68 UJ 0.55 U 18 J 72 0.53 U 0.57 U 0.59 U 2.5 U 0.56 U Indeno[1,2,3-cd]pyrene 0.69 U 7.1 57 0.65 U 0.62 UJ 0.82 UJ 14 11 J 82 14 0.68 U 0.71 U 22 J 0.68 U Naphthalene 0.92 U 21 53 0.87 U 2 J 1.1 UJ 22 78 700 31 5.9 18 52 1.2 J Phenanthrene 5.8 U 70 89 5.4 U 2.7 J 1.7 J 27 120 660 39 3.5 J 5.6 J 48 2.3 J Pyrene 1.1 U 46 66 1.1 U 1 UJ 1.3 UJ 17 62 340 23 1.1 U 13 26 1.1 U NWTPH (mg/kg) Gasoline 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U Diesel 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U Oil 250 U 250 U ------

Page 2 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 0+00 EW1 0+00 NW1 0+50 SW1 0+50 EW1 0+50 F 0+50 NW 0+75 SW1 0+75 F1 0+75 NW1 1+00 SW1 1+00 F 1+00 NW 1+25 SW1 1+25 F Type Sidewall Sidewall Sidewall Sidewall Floor Sidewall Sidewall Floor Sidewall Sidewall Floor Sidewall Sidewall Floor Depth (ft bgs) 3 3 3 3 4.5 4 4 4 3 5 4 4 5 4 Date Sampled 6/9/16 6/9/16 6/11/16 6/9/16 6/21/16 6/21/16 6/11/16 6/11/16 6/11/16 6/10/16 6/21/16 6/21/16 6/10/16 6/21/16 NWTPH/VPH - Volatile Petroleum Hydrocarbons (mg/kg) C5-C6 Aliphatics ------C6-C8 Aliphatics ------C8-C10 Aliphatics ------C8-C10 Aromatics ------C10-C12 Aliphatics ------C10-C12 Aromatics ------C12-C13 Aromatics ------Total VPH ------NWTPH/EPH - Extractable Petroleum Hydrocarbons (mg/kg) C8-C10 Aliphatics ------C8-C10 Aromatics ------C10-C12 Aliphatics ------C10-C12 Aromatics ------C12-C16 Aliphatics ------C12-C16 Aromatics ------C16-C21 Aliphatics ------C16-C21 Aromatics ------C21-C34 Aliphatics ------C21-C34 Aromatics ------Moisture Content (percent) Percent Moisture - - 6.8 13.7 20.5 36.2 10.9 22.8 24.4 10.2 16.6 20.4 7.4 19.6 Percent Solids - - 93.2 86.3 79.5 63.8 89.1 77.2 75.6 89.8 83.4 79.6 92.6 80.4 Notes Results shown in bold denote detected concentrations. 1 Detection limits for VOCs identified as laboratory reporting limit and NWTPH-Gx and NWTPH-Dx identified as Practical Quantitation Limit. No method detection limit values available. µg/kg = micrograms per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J - Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U - Analyte was not detected above the method detection limit (MDL).

Page 3 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 1+25 NW 1+50 SW1 1+50 F 1+50 NF 1+50 NW 1+75 SW1 1+75 EW1 1+75 F 1+75 NF 2+00 SW1 2+00 SF1 2+00 NF1 2+00 NW1 2+25 NF1 Type Sidewall Sidewall Floor Floor Sidewall Sidewall Sidewall Floor Floor Sidewall Floor Floor Sidewall Floor Depth (ft bgs) 3.5 6 8 8 3.5 10 9 7 7 11 15 14 5 16 Date Sampled 6/21/16 6/11/16 6/21/16 6/21/16 6/21/16 6/11/16 6/11/16 6/21/16 6/21/16 6/11/16 6/11/16 6/11/16 6/10/16 6/10/16 Volatile Organic Compounds (mg/kg) 1,1,1,2-Tetrachloroethane - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1,1-Trichloroethane (TCA) - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,1,2,2-Tetrachloroethane - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1,2-Trichloroethane - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1-Dichloroethane - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1-Dichloroethene - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,1-Dichloropropene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,2,3-Trichlorobenzene - 0.10 U - - - 0.10 U 0.10 U - - 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 1,2,3-Trichloropropane - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2,4-Trichlorolbenzene - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,2,4-Trimethylbenzene - 0.02 U - - - 0.2 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,2-Dibromo-3-Chloropropane - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,2-Dibromoethane (EDB) * - 0.005 U - - - 0.005 U 0.005 U - - 0.005 U 0.005 U 0.005 U 0.005 U 0.005 U 1,2-Dichlorobenzene - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2-Dichloroethane (EDC) - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2-Dichloropropane - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,3,5-Trimethylbenzene - 0.02 U - - - 0.03 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,3-Dichlorobenzene - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,3-Dichloropropane - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,4-Dichlorobenzene - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 2,2-Dichloropropane - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 2-Chlorotoluene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 4-Chlorotoluene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Benzene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Bromobenzene - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Bromodichloromethane - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Bromoform - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Bromomethane - 0.09 U - - - 0.09 U 0.09 U - - 0.09 U 0.09 U 0.09 U 0.09 U 0.09 U Carbon tetrachloride - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Chlorobenzene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Chloroethane - 0.06 U - - - 0.06 U 0.06 U - - 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U Chloroform - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Chloromethane - 0.06 U - - - 0.06 U 0.06 U - - 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U cis -1,2-Dichloroethene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U cis-1,3-Dichloropropene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Dibromochloromethane - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Dibromomethane - 0.04 U - - - 0.04 U 0.04 U - - 0.04 U 0.04 U 0.04 U 0.04 U 0.04 U Dichlorodifluoromethane - 0.06 U - - - 0.06 U 0.06 U - - 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U Ethylbenzene - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Hexachloro-1,3-butadiene - 0.10 U - - - 0.10 U 0.10 U - - 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U Isopropylbenzene - 0.08 U - - - 0.08 U 0.08 U - - 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U

Page 4 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 1+25 NW 1+50 SW1 1+50 F 1+50 NF 1+50 NW 1+75 SW1 1+75 EW1 1+75 F 1+75 NF 2+00 SW1 2+00 SF1 2+00 NF1 2+00 NW1 2+25 NF1 Type Sidewall Sidewall Floor Floor Sidewall Sidewall Sidewall Floor Floor Sidewall Floor Floor Sidewall Floor Depth (ft bgs) 3.5 6 8 8 3.5 10 9 7 7 11 15 14 5 16 Date Sampled 6/21/16 6/11/16 6/21/16 6/21/16 6/21/16 6/11/16 6/11/16 6/21/16 6/21/16 6/11/16 6/11/16 6/11/16 6/10/16 6/10/16 Isopropyltoluene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Methyl tert- Butyl Ether (MTBE) - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Methylene chloride - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Naphthalenes - 0.05 U - - - 0.1 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U n-Butylbenzene - 0.02 U - - - 0.1 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U n-Propylbenzene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U sec-Butylbenzene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Styrene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U tert-Butylbenzene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Tetrachloroethene (PCE) - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Toluene - 0.10 U - - - 0.10 U 0.10 U - - 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U Total Xylenes - 0.15 U - - - 0.15 U 0.15 U - - 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U trans -1,2-Dichloroethene - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Trans-1,3-Dichloropropene - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Trichloroethene (TCE) - 0.03 U - - - 0.03 U 0.03 U - - 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Trichlorofluoromethane - 0.05 U - - - 0.05 U 0.05 U - - 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Vinyl chloride - 0.02 U - - - 0.02 U 0.02 U - - 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Semi-volatile Organic Compounds (µg/ 1-Methylnaphthalene 1.6 J 790 0.74 U 1.1 J 0.71 U 340 0.68 U 2.3 J 3.4 J 16 0.72 U 0.65 U 130 520 2-Methylnaphthalene 2.6 J 800 1.7 J 1.9 J 1.2 J 390 0.48 U 2.4 J 3.9 J 21 0.51 U 0.47 U 130 500 Acenaphthene 0.61 U 3.9 U 0.71 U 0.63 U 0.68 U 24 J 0.65 U 0.64 U 1.4 J 0.63 U 0.69 U 0.62 U 4.6 J 0.71 U Acenaphthylene 0.51 U 25 J 0.59 U 0.52 U 0.56 U 39 0.54 U 0.53 U 1.3 J 1.6 J 0.57 U 0.52 U 14 780 Anthracene 0.61 U 52 0.71 U 0.63 U 0.68 U 37 0.65 U 0.64 U 1.3 J 2 J 0.69 U 0.62 U 23 150 Benzo[a]anthracene 0.77 U 83 0.89 U 0.8 U 0.86 U 46 0.82 U 0.81 U 1.5 J 0.79 U 0.87 U 0.79 U 30 91 Benzo[a]pyrene 0.41 U 61 0.47 U 0.42 U 0.45 U 38 0.43 U 0.43 U 1.3 J 0.42 U 0.46 U 0.41 U 11 52 Benzo[b]fluoranthene 0.6 U 95 0.69 U 0.62 U 0.66 U 81 0.63 U 0.63 U 1.6 J 0.62 U 0.67 U 0.61 U 42 130 Benzo[g,h,i]perylene 0.51 U 56 0.59 U 0.52 U 0.56 U 42 0.54 U 0.53 U 0.53 UJ 0.52 U 0.57 U 0.52 U 13 35 Benzo[k]fluoranthene 0.61 U 23 J 0.71 U 0.63 U 0.68 U 32 0.65 U 0.64 U 1.6 J 0.63 U 0.69 U 0.62 U 12 23 Chrysene 1.5 U 130 1.8 U 1.6 U 1.7 U 120 1.6 U 1.6 U 1.7 J 1.6 U 1.7 U 1.6 U 45 120 Dibenz(a,h)anthracene 0.73 U 4.7 U 0.85 U 0.75 U 0.81 U 6.9 J 0.77 U 0.77 U 0.77 UJ 0.75 U 0.82 U 0.75 U 0.88 U 0.85 U Fluoranthene 2.0 J 100 1.7 J 2.0 J 1.6 J 130 1.5 J 1.5 U 2.2 J 1.5 U 1.6 U 1.5 U 120 500 Fluorene 0.51 U 22 J 0.59 U 0.52 U 0.56 U 54 0.54 U 0.53 U 0.53 UJ 3.7 J 0.57 U 0.52 U 8.9 53 Indeno[1,2,3-cd]pyrene 0.61 U 54 0.71 U 0.63 U 0.68 U 44 0.65 U 0.64 U 0.64 UJ 0.63 U 0.69 U 0.62 U 15 45 Naphthalene 10 470 8.3 8.2 4.5 J 120 0.86 U 1.2 J 1.9 J 9.5 0.91 U 0.83 U 110 2,600 Phenanthrene 5.5 360 4.8 J 4.5 J 3.1 J 270 1.3 J 2.9 J 3.7 J 6.4 0.79 U 0.72 U 100 680 Pyrene 1.5 J 150 1.1 U 1 U 1.5 J 120 1 U 1 U 2 J 1 U 1.1 U 1 U 77 390 NWTPH (mg/kg) Gasoline 10 U 10 U 10 U 10 U 10 U 48 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U Diesel 50 U 530 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U Oil ------

Page 5 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 1+25 NW 1+50 SW1 1+50 F 1+50 NF 1+50 NW 1+75 SW1 1+75 EW1 1+75 F 1+75 NF 2+00 SW1 2+00 SF1 2+00 NF1 2+00 NW1 2+25 NF1 Type Sidewall Sidewall Floor Floor Sidewall Sidewall Sidewall Floor Floor Sidewall Floor Floor Sidewall Floor Depth (ft bgs) 3.5 6 8 8 3.5 10 9 7 7 11 15 14 5 16 Date Sampled 6/21/16 6/11/16 6/21/16 6/21/16 6/21/16 6/11/16 6/11/16 6/21/16 6/21/16 6/11/16 6/11/16 6/11/16 6/10/16 6/10/16 NWTPH/VPH - Volatile Petroleum Hydr C5-C6 Aliphatics ------1.5 U - - - - C6-C8 Aliphatics ------0.35 U - - - - C8-C10 Aliphatics ------3.1 J - - - - C8-C10 Aromatics ------1.6 J - - - - C10-C12 Aliphatics ------7.8 - - - - C10-C12 Aromatics ------6.1 J - - - - C12-C13 Aromatics ------12 - - - - Total VPH ------33 J - - - - NWTPH/EPH - Extractable Petroleum H C8-C10 Aliphatics ------0.99 J - - - - C8-C10 Aromatics ------1.2 U - - - - C10-C12 Aliphatics ------7.5 - - - - C10-C12 Aromatics ------0.53 J - - - - C12-C16 Aliphatics ------28 - - - - C12-C16 Aromatics ------3.6 J - - - - C16-C21 Aliphatics ------31 - - - - C16-C21 Aromatics ------13 - - - - C21-C34 Aliphatics ------43 - - - - C21-C34 Aromatics ------17 - - - - Moisture Content (percent) Percent Moisture 19.1 27.2 17.6 23.1 15 8.7 9 19.5 17.8 17.2 22.1 9.0 22.5 18.6 Percent Solids 80.9 72.8 82.4 76.9 85 91.3 91 80.5 82.2 82.8 77.9 91.0 77.5 81.4 Notes Results shown in bold denote detected concentrations. 1 Detection limits for VOCs identified as laboratory reporting limit and NWTPH-Gx and NWTPH-Dx identified as Practical Quantitation Limit. No method detection limit values available. µg/kg = micrograms per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J - Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U - Analyte was not detected above the method detection limit (MDL).

Page 6 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 2+25 NW1 2+50 DF1 2+50 NF1 2+50 WW1 2+50 NW1 2+75 ST1 3+00 ST1 3+25 ST1 Type Sidewall Floor (Deep) Floor Sidewall Sidewall Floor Floor Floor Depth (ft bgs) 8 5 22 15 18 5 5 5 Date Sampled 6/10/16 6/11/16 6/10/16 6/11/16 6/10/16 6/11/16 6/11/16 6/11/16 Volatile Organic Compounds (mg/kg) 1,1,1,2-Tetrachloroethane 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1,1-Trichloroethane (TCA) 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,1,2,2-Tetrachloroethane 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1,2-Trichloroethane 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1-Dichloroethane 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,1-Dichloroethene 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,1-Dichloropropene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,2,3-Trichlorobenzene 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 1,2,3-Trichloropropane 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2,4-Trichlorolbenzene 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,2,4-Trimethylbenzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,2-Dibromo-3-Chloropropane 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,2-Dibromoethane (EDB) * 0.005 U 0.005 U 0.005 U 0.005 U 0.005 U 0.005 U 0.005 U 0.005 U 1,2-Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2-Dichloroethane (EDC) 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,2-Dichloropropane 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,3,5-Trimethylbenzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 1,3-Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 1,3-Dichloropropane 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 1,4-Dichlorobenzene 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 2,2-Dichloropropane 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 2-Chlorotoluene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 4-Chlorotoluene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Benzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Bromobenzene 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Bromodichloromethane 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Bromoform 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Bromomethane 0.09 U 0.09 U 0.09 U 0.09 U 0.09 U 0.09 U 0.09 U 0.09 U Carbon tetrachloride 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Chlorobenzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Chloroethane 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U Chloroform 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Chloromethane 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U cis -1,2-Dichloroethene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U cis-1,3-Dichloropropene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Dibromochloromethane 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Dibromomethane 0.04 U 0.04 U 0.04 U 0.04 U 0.04 U 0.04 U 0.04 U 0.04 U Dichlorodifluoromethane 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U 0.06 U Ethylbenzene 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Hexachloro-1,3-butadiene 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U Isopropylbenzene 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U

Page 7 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 2+25 NW1 2+50 DF1 2+50 NF1 2+50 WW1 2+50 NW1 2+75 ST1 3+00 ST1 3+25 ST1 Type Sidewall Floor (Deep) Floor Sidewall Sidewall Floor Floor Floor Depth (ft bgs) 8 5 22 15 18 5 5 5 Date Sampled 6/10/16 6/11/16 6/10/16 6/11/16 6/10/16 6/11/16 6/11/16 6/11/16 Isopropyltoluene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Methyl tert- Butyl Ether (MTBE) 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Methylene chloride 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Naphthalenes 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U n-Butylbenzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U n-Propylbenzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U sec-Butylbenzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Styrene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U tert-Butylbenzene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Tetrachloroethene (PCE) 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Toluene 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U 0.10 U Total Xylenes 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U trans -1,2-Dichloroethene 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Trans-1,3-Dichloropropene 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Trichloroethene (TCE) 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U 0.03 U Trichlorofluoromethane 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U 0.05 U Vinyl chloride 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U 0.02 U Semi-volatile Organic Compounds (µg/ 1-Methylnaphthalene 340 0.66 U 2.2 J 9 420 9 0.66 U 0.74 U 2-Methylnaphthalene 360 0.47 U 2.2 J 11 450 7.7 0.47 U 0.53 U Acenaphthene 7.9 0.62 U 2.3 J 1.7 J 0.70 U 0.67 U 0.63 U 0.7 U Acenaphthylene 60 0.52 U 0.59 U 0.58 U 27 0.56 U 0.52 U 0.59 U Anthracene 110 0.62 U 1.2 J 1.4 J 58 1.7 J 0.63 U 0.7 UJ Benzo[a]anthracene 100 0.79 U 2.8 J 3.2 J 77 5.6 0.8 U 0.89 U Benzo[a]pyrene 70 0.42 U 1.1 J 2.1 J 38 4.7 J 0.42 U 0.47 UJ Benzo[b]fluoranthene 240 0.61 U 2.2 J 3.8 J 110 8 0.62 U 0.69 U Benzo[g,h,i]perylene 77 0.52 U 0.59 U 0.58 U 23 3 J 0.52 U 0.59 U Benzo[k]fluoranthene 47 0.62 U 0.92 J 1.7 J 20 2.4 J 0.63 U 0.7 U Chrysene 240 1.6 U 2.7 J 3.3 J 140 9.7 1.6 U 1.8 U Dibenz(a,h)anthracene 19 0.75 U 0.84 U 0.84 U 0.84 U 0.8 U 0.75 U 0.84 U Fluoranthene 360 1.5 U 9.2 7.5 280 8.2 1.5 U 1.6 U Fluorene 20 0.52 U 1.5 J 0.58 U 0.58 U 0.56 U 0.52 U 0.59 U Indeno[1,2,3-cd]pyrene 79 0.62 U 1.6 J 1.8 J 25 3.3 J 0.63 U 0.7 U Naphthalene 290 0.83 U 0.94 U 13 270 4.7 J 0.84 U 0.94 U Phenanthrene 470 0.72 U 8.9 7.3 360 12 0.72 U 2.1 J Pyrene 250 1 U 7 6.9 180 8.3 1 U 1.1 U NWTPH (mg/kg) Gasoline 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U Diesel 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U Oil ------

Page 8 of 9 Table 3-6. Final Confirmation Soil Sample Results (Characteristic of Soil Left in Place) Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID 2+25 NW1 2+50 DF1 2+50 NF1 2+50 WW1 2+50 NW1 2+75 ST1 3+00 ST1 3+25 ST1 Type Sidewall Floor (Deep) Floor Sidewall Sidewall Floor Floor Floor Depth (ft bgs) 8 5 22 15 18 5 5 5 Date Sampled 6/10/16 6/11/16 6/10/16 6/11/16 6/10/16 6/11/16 6/11/16 6/11/16 NWTPH/VPH - Volatile Petroleum Hydr C5-C6 Aliphatics ------1.4 U - C6-C8 Aliphatics ------0.32 U - C8-C10 Aliphatics ------0.64 U - C8-C10 Aromatics ------1.1 U - C10-C12 Aliphatics ------0.27 U - C10-C12 Aromatics ------0.36 U - C12-C13 Aromatics ------1.3 J - Total VPH ------45 U - NWTPH/EPH - Extractable Petroleum H C8-C10 Aliphatics ------0.03 U - C8-C10 Aromatics ------1.1 U - C10-C12 Aliphatics ------0.11 U - C10-C12 Aromatics ------0.08 U - C12-C16 Aliphatics ------1.1 U - C12-C16 Aromatics ------1.1 U - C16-C21 Aliphatics ------1.1 U - C16-C21 Aromatics ------1.1 U - C21-C34 Aliphatics ------1.1 U - C21-C34 Aromatics ------1.1 U - Moisture Content (percent) Percent Moisture 18.4 11.3 16 21.1 14.5 14.8 13.1 15.5 Percent Solids 81.6 88.7 84 78.9 85.5 85.2 86.9 84.5 Notes Results shown in bold denote detected concentrations. 1 Detection limits for VOCs identified as laboratory reporting limit and NWTPH-Gx and NWTPH-Dx identified as Practical Quantitation Limit. No method detection limit values available. µg/kg = micrograms per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J - Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U - Analyte was not detected above the method detection limit (MDL).

Page 9 of 9 Table 3‐7. Pothole Soil Sample Results Near WWTP Manhole Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID Pothole‐1 Pothole‐2 Pothole‐3 Pothole‐4 Sample Date 6/15/16 14:07 6/15/16 14:07 6/15/16 14:07 6/15/16 14:07 Pothole Depth 3 Feet 3 Feet 5 Feet 3 Feet Volatile Organic Compounds (µg/kg) 1,1,1,2‐Tetrachloroethane 4.1 UJ 4 UJ 5.8 UJ 4.4 UJ 1,1,1‐Trichloroethane 6 UJ 5.9 UJ 8.5 UJ 6.5 UJ 1,1,2,2‐Tetrachloroethane 2.5 UJ 2.4 UJ 3.5 UJ 2.7 UJ 1,1,2‐Trichloroethane 3 UJ 2.9 UJ 4.3 UJ 3.2 UJ 1,1‐Dichloroethane 4.5 UJ 4.4 UJ 6.4 UJ 4.9 UJ 1,1‐Dichloroethene 5.3 UJ 5.1 UJ 7.5 UJ 5.7 UJ 1,1‐Dichloropropene 5.7 UJ 5.6 UJ 8.1 UJ 6.1 UJ 1,2,3‐Trichlorobenzene 16 UJ 15 UJ 22 UJ 17 UJ 1,2,3‐Trichloropropane 12 UJ 26 J 18 UJ 13 UJ 1,2,3‐Trimethylbenzene 150 J 12,000 J 12 UJ 12 J 1,2,4‐Trichlorobenzene 17 UJ 16 UJ 23 UJ 18 UJ 1,2,4‐Trimethylbenzene 270 J 23,000 J 61 U 46 U 1,2‐Dibromo‐3‐Chloropropane 7.8 UJ 7.5 UJ 11 UJ 8.3 UJ 1,2‐Dibromoethane 3.7 UJ 3.6 UJ 5.2 UJ 3.9 UJ 1,2‐Dichlorobenzene 4.9 UJ 4.7 UJ 6.9 UJ 5.2 UJ 1,2‐Dichloroethane 3.6 UJ 3.5 UJ 5 UJ 3.8 UJ 1,2‐Dichloropropane 2.6 UJ 2.5 UJ 3.7 UJ 2.8 UJ 1,3,5‐Trimethylbenzene 92 J 6,200 J 12 UJ 8.8 UJ 1,3‐Dichlorobenzene 6.4 UJ 6.2 UJ 9 UJ 6.8 UJ 1,3‐Dichloropropane 5.9 UJ 5.8 UJ 8.4 UJ 6.4 UJ 1,4‐Dichlorobenzene 12 UJ 11 UJ 16 UJ 13 UJ 2,2‐Dichloropropane 13 UJ 13 UJ 18 UJ 14 UJ 2‐Chlorotoluene 3.7 UJ 3.6 UJ 5.2 UJ 3.9 UJ 4‐Chlorotoluene 3.2 UJ 3.1 UJ 4.6 UJ 3.5 UJ 4‐Isopropyltoluene 34 J 2,300 J 12 UJ 9 UJ Benzene 26 J 130 J 3.2 UJ 2.4 UJ Bromobenzene 2.6 UJ 2.5 UJ 3.7 UJ 2.8 UJ Bromochloromethane 13 UJ 13 UJ 19 UJ 14 UJ Bromodichloromethane 4 UJ 3.9 UJ 5.6 UJ 4.3 UJ Bromoform 28 UJ 28 UJ 40 UJ 30 UJ Bromomethane 14 UJ 14 UJ 20 UJ 16 UJ Carbon tetrachloride 4.1 UJ 4 UJ 5.8 UJ 4.4 UJ Chlorobenzene 11 UJ 10 UJ 15 UJ 11 UJ Chloroethane 17 UJ 17 UJ 24 UJ 18 UJ Chloroform 4.5 UJ 4.4 UJ 6.4 UJ 4.9 UJ Chloromethane 11 UJ 11 UJ 15 UJ 12 UJ cis‐1,2‐Dichloroethene 5.3 UJ 5.1 UJ 7.5 UJ 5.7 UJ cis‐1,3‐Dichloropropene 1.9 UJ 1.9 UJ 2.7 UJ 2.1 UJ Dibromochloromethane 3 UJ 2.9 UJ 4.3 UJ 3.2 UJ Dibromomethane 8 UJ 7.8 UJ 11 UJ 8.6 UJ Dichlorodifluoromethane 49 UJ 48 UJ 70 UJ 53 UJ Ethylbenzene 38 J 2,300 J 10 UJ 7.8 UJ Hexachlorobutadiene 20 UJ 19 UJ 28 UJ 21 UJ Isopropylbenzene 27 J 2,000 J 13 UJ 10 UJ Methyl tert‐butyl ether 6.5 UJ 6.3 UJ 9.1 UJ 6.9 UJ Methylene Chloride 7.3 UJ 7.1 UJ 10 UJ 7.9 UJ m‐Xylene & p‐Xylene 190 J 13,000 J 59 UJ 44 UJ Naphthalene 43 U 1,700 J 150 J 15 UJ n‐Butylbenzene 57 J 4,300 J 18 UJ 14 UJ N‐Propylbenzene 39 J 3,200 J 10 UJ 7.9 UJ o‐Xylene 110 J 7,300 J 4.6 UJ 6.7 J sec‐Butylbenzene 30 J 2,200 J 12 UJ 9.4 UJ Styrene 6.6 UJ 39 J 9.3 UJ 7.1 UJ t‐Butylbenzene 8.3 UJ 110 J 12 UJ 8.9 UJ Tetrachloroethene 5.7 UJ 5.6 UJ 8.1 UJ 6.1 UJ Toluene 82 J 2,400 J 10 UJ 7.9 UJ trans‐1,2‐Dichloroethene 16 UJ 15 UJ 22 UJ 17 UJ trans‐1,3‐Dichloropropene 7.5 UJ 7.3 UJ 11 UJ 8.1 UJ Trichloroethene 3.3 UJ 3.2 UJ 4.7 UJ 3.6 UJ Trichlorofluoromethane 40 UJ 39 UJ 57 UJ 43 UJ Vinyl chloride 7.7 UJ 7.4 UJ 11 UJ 8.2 UJ Semi‐volatile Organic Compounds (µg/kg) 1‐Methylnaphthalene 30 8,800 4.9 3.1 U 2‐Methylnaphthalene 23 10,000 6.1 2.2 U Acenaphthene 1.3 J 140 0.55 U 3 U Acenaphthylene 3.2 J 260 0.46 U 2.5 U Anthracene 1.4 J 73 0.55 U 3 U Benzo[a]anthracene 1.4 J 38 0.7 U 3.8 U Benzo[a]pyrene 0.45 UJ 23 1.5 J 2U Benzo[b]fluoranthene 1.6 J 19 2.3 J 2.9 U Benzo[g,h,i]perylene 1.2 J 9.4 2.9 J 2.5 U

Page 1 of 2 Table 3‐7. Pothole Soil Sample Results Near WWTP Manhole Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID Pothole‐1 Pothole‐2 Pothole‐3 Pothole‐4 Sample Date 6/15/16 14:07 6/15/16 14:07 6/15/16 14:07 6/15/16 14:07 Benzo[k]fluoranthene 0.67 U 4.4 J 1 J 3U Chrysene 3.9 J 260 1.4 U 7.5 U Dibenz(a,h)anthracene 0.81 U 0.69 U 0.66 U 3.6 U Fluoranthene 2.7 J 98 2.4 J 7U Fluorene 5.5 J 310 0.46 U 2.5 U Indeno[1,2,3‐cd]pyrene 1.1 J 0.57 U 1.9 J 3U Naphthalene 6.7 2,100 2 J 4U Phenanthrene 17 2,100 3.3 J 3.4 U Pyrene 3.3 J 160 2.3 J 4.8 U NWTPH (mg/kg) Gasoline 31 2,000 0.64 U 4.8 #2 Diesel (C10‐C24) 84 6,900 13 J 10 U Motor Oil (>C24‐C36) 94 4,900 110 62 Moisture Content (percent) Percent Moisture 15.3 10.3 18.1 9.3 Percent Solids 84.7 89.7 81.9 90.7 Notes: Results shown in bold denote detected concentrations. µg/kg = micrograms per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 2 of 2 Table 3‐8. MainlineTrack Confirmation Soil Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID Track 1 FL Track 2 FL Track 3 South Wall Track 4 South Wall Track 5 FL Track 6 North Wall Track 7 North Wall Track 8 Floor Track 9 Floor Track 10 North Wall Track 11 Floor Sample Date 6/6/16 4:30 6/6/16 5:00 6/6/16 4:40 6/6/16 5:15 6/6/16 5:25 6/6/16 5:30 6/6/16 5:40 6/6/16 5:50 6/6/16 5:55 6/6/16 6:10 6/6/16 6:20 Sample Depth 5 feet 5 feet 6 Feet 6 feet 5 feet 7 Feet 5 feet 5 feet 7 Feet 6 Feet 5 Feet Semi‐volatile Organic Compounds (µg/kg) 1‐Methylnaphthalene 29 20 25 47 190 29 54 190 19 70 150 2‐Methylnaphthalene 40 29 34 25 290 38 75 290 18 98 100 Acenaphthene 16 16 19 0.66 U 130 20 J 26 94 0.6 U 39 10 Acenaphthylene 7.5 6.3 9.1 4.4 J 160 10 J 27 190 0.5 U 18 25 Anthracene 25 25 28 0.66 U 550 37 52 590 3.2 J 64 23 Benzo[a]anthracene 41 32 33 0.83 U 1,200 71 98 540 1.1 J 84 8.9 Benzo[a]pyrene 15 13 23 0.44 U 970 43 49 480 0.4 U 37 4.6 J Benzo[b]fluoranthene 45 30 49 0.65 U 1,300 79 97 650 1.7 J 97 6.5 Benzo[g,h,i]perylene 18 15 34 0.55 U 1,600 46 43 1,200 0.5 U 48 5.5 Benzo[k]fluoranthene 13 11 13 0.66 U 540 30 27 280 0.71 J 28 2.6 J Chrysene 62 50 57 1.6 U 1,400 110 130 750 3.9 J 120 36 Dibenz(a,h)anthracene 0.71 U 2.4 J 4.9 J 0.79 U 170 8.3 J 7.6 110 0.72 U 13 0.73 U Fluoranthene 210 190 170 7.2 3,000 310 410 1,400 4.4 J 430 30 Fluorene 28 24 25 12 140 33 53 110 4.8 J 64 35 Indeno[1,2,3‐cd]pyrene 19 13 38 0.66 U 1,300 40 47 800 0.6 U 62 5.5 Naphthalene 25 19 34 0.88 U 230 29 66 260 0.8 U 68 0.81 U Phenanthrene 120 110 95 35 1,200 150 200 900 20 280 97 Pyrene 160 140 130 9.4 2,500 260 320 1,200 6.3 330 35 NWTPH (mg/kg) Gasoline 2.2 J 1.9 J 2.7 J 23 21 4.6 6.4 5.2 15 6.8 12 #2 Diesel (C10‐C24) 51 40 39 85 200 52 92 250 57 92 350 Motor Oil (>C24‐C36) 83 87 70 73 670 97 190 960 61 200 360 J Moisture Content (percent) Percent Moisture 11.6 9.7 11.6 11.2 5.7 12.1 12.5 7.4 12.3 11.3 12.4 Percent Solids 88.4 90.3 88.4 88.8 94.3 87.9 87.5 92.6 87.7 88.7 87.6 Notes: Results shown in bold denote detected concentrations. µg/kg = micrograms per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 1 of 1 Table 3-9. Miscellaneous Soil Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID Soil Pile Stockpile-060616 CleanFill Sample Date 6/6/2016 8:30 6/6/2016 16:35 6/11/16 13:15 Volatile Organic Compounds (µg/kg) Benzene 150 - 4.7 J Semi-volatile Organic Compounds (µg/kg) 1-Methylnaphthalene - 11,000 26 J 2-Methylnaphthalene - 13,000 30 J Acenaphthene - 1,300 0.61 UJ Acenaphthylene - 490 J 0.51 UJ Anthracene - 1,300 J 0.61 UJ Benzo[a]anthracene - 950 J 0.77 UJ Benzo[a]pyrene - 410 J 0.41 UJ Benzo[b]fluoranthene - 590 J 2 J Benzo[g,h,i]perylene - 130 J 0.51 UJ Benzo[k]fluoranthene - 64 0.61 UJ Chrysene - 1,500 J 1.5 UJ Dibenz(a,h)anthracene - 35 J 0.73 UJ Fluoranthene - 3,300 J 5.7 J Fluorene - 1,500 J 4.7 J Indeno[1,2,3-cd]pyrene - 150 J 0.61 UJ Naphthalene - 4,100 4.8 J Phenanthrene - 6,800 21 J Pyrene - 4,800 J 6.7 J NWTPH/VPH - Volatile Petroleum Hydrocarbons (mg/kg) C5-C6 Aliphatics - 10 - C6-C8 Aliphatics - 23 J - C8-C10 Aliphatics - 120 - C8-C10 Aromatics - 96 - C10-C12 Aliphatics - 93 - C10-C12 Aromatics - 150 J - C12-C13 Aromatics - 210 - Total VPH - 770 - NWTPH/EPH - Extractable Petroleum Hydrocarbons (mg/kg) C8-C10 Aliphatics - 130 - C8-C10 Aromatics - 24 J - C10-C12 Aliphatics - 460 - C10-C12 Aromatics - 94 J - C12-C16 Aliphatics - 1,400 - C12-C16 Aromatics - 310 - C16-C21 Aliphatics - 2,000 - C16-C21 Aromatics - 1,000 - C21-C34 Aliphatics - 3,900 - C21-C34 Aromatics - 1,900 - TCLP Benzene (mg/L) Benzene 0.042 U - - TCLP Metals (mg/L) Arsenic 0.013 J - - Barium 0.26 - - Cadmium 0.0006 J - - Chromium 0.0056 J - - Lead 0.0049 J - - Selenium 0.0054 U - - Silver 0.0085 U - - Mercury 0.00041 U - - NWTPH (mg/kg) Motor Oil (>C24-C36) - - 190 #2 Diesel (C10-C24) - - 270 General Chemistry Percent Moisture (%) 5.6 14.2 12.7 Percent Solids (%) 94.4 85.8 87.3 Flashpoint (Degrees F) >211 - - Notes: Results shown in bold denote detected concentrations. µg/kg = micrograms per kilogram mg/kg = milligram(s) per kilogram NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J - Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value. U - Analyte was not detected above the method detection limit (MDL).

Page 1 of 1

Figures

VICINITY MAP Observed Sheen Columbia River through Outfall C C o ll u rr Manhole and Effluent Pipe u m b ii a RR ii vv ee INTERSTATE 84

Extent Shown in Main Map

W e s t e r n L a k e INTERSTATE 84 DERAILMENT DRONE PHOTOGRAPH

Rock Creek 68.8

Extent Shown in (Historic Columbia River Highway) Derailment Drone Photograph DERAILMENT, JUNE 3, 2016 Rock Creek Road

68.9 E a s t L a k e

69 City of Mosier Highway 30 Overpass Wastewater Treatment Plant

Service Layer Credits: © OpenStreetMap (and) contributors, CC-BY-SA Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, LEGEND Aerogrid, IGN, IGP, swisstopo, and the GIS User Community Cars that Did Not Leak or Burn Rock Creek Location of Cars and Fire Railroad Tracks Burn Area Wetland Approximate Sheen Extent, June 4, 2016 Notes: WWTP = wastewater treatment plant !. Manhole FIGURE 1-1 WWTP Pipeline SITE FEATURES 0 50 100 150 200 CITY OF MOSIER WWTP UNION PACIFIC RAILROAD $ Feet WASCO COUNTY, OREGON Milepost

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\SITE_ASSESSMENT\FIGURE1-1_SITEFEATURES.MXD GGEE 10/26/2016 11:14:13 AM Columbia River

Outer Boom Boom Placement to Contain Sheen

INTERSTATE 84 Inner Boom Submerged Outfall

68.6

INTERSTATE 84

W e s t e r n Effluent Line Cleaned by Jet-Rod L a k e 68.7

Rock Creek 68.8 !U MW-8 !U MW-1 !U MW-2 !U MW-3 !U MW-7 !U MW-6 !U !U WWTP Equipment 68.9 MW-4 MW-5 Soil Excavation Area Decontaminated or Replaced !UEW-1!UEW-2 Influent Line Replaced E a s t L a k e 69 Manhole #2 Manhole #3

Influent Line and Manhole Replaced Manhole #4

Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, LEGEND AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community !U Extraction Well Excavation Area !U Monitoring Well WWTP Approximate Boom Location Rock Creek Approximate Sheen Extent, June 4, 2016 Wetland !. Manhole FIGURE 1-2 Notes: WWTP = wastewater treatment plant INITIAL RESPONSE ACTIONS WWTP Pipeline 0 100 200 300 400 CITY OF MOSIER UNION PACIFIC RAILROAD Milepost $ Feet WASCO COUNTY, OREGON

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\SITE_ASSESSMENT\FIGURE1-2_RESPONSEACTIONSV2.MXD GGEE 10/26/2016 11:29:14 AM 3+003+25 ST ST 2+75 STDepth = 5 ft bgs 2+00 SW DepthDepth = 5 =ft 5bgs ft bgs 1+501+75 SW SW 2+502+50 NF6/11/2016 6/11/2016WW 1+001+25 SW SW1+75Depth2+00 EW SF= 116/11/2016 ft bgs 0+75 SW 1+50Depth F = 10Depth ft bgsDepth Dx= 22 Dx= = NDft 15 =bgs ND ft bgs 0+500+75 EWDepth FDepth1+25 Depth= 5 F=ft1+75 5bgs = 6/11/2016ftDepth 6bgs ftF bgs = 15Dx ft =bgs ND 0+50Depth NW1+00 = 4 F ft bgsDepth6/11/2016 = 9 ft6/10/2016 bgs6/11/2016Gx = ND Depth = 3 ft6/11/2016Depth 1+25bgs6/11/2016Depth NW=Depth 4 Dx= 6/11/2016ft 8 bgs= ft= ND bgs7 ft bgsGx =Gx ND = ND 6/11/2016Depth0+756/11/2016Depth1+00 NW = 4 NW =ft 46/11/2016bgsDx ft bgs= ND Dx = ND 3+25 6/9/2016Depth = 4Dx 6/21/2016ftDepth bgsDx=6/21/2016 ND = 6/21/2016 =530 3.5GxDx mg/kg =ft= NDbgsND Dx =3+00 ND 6/21/2016Dx6/11/2016Depth =Dx6/21/2016Depth ND = = ND 3 =ft Dx4bgsGx ft = bgs= ND 48 mg/kgGx = ND2+75 Dx = ND GxDx6/21/2016 Gx= Dx= ND ND= =Dx ND ND Gx= ND = ND Gx = ND DxGx Dx=6/11/2016 ND Gx =Dx=6/21/2016 NDND == NDNDGx = ND Gx = ND GxDx Gx == NDND =Gx ND = ND Gx Gx=Dx ND Gx=Dx ND == NDND 2+50 0+000+250+50Gx =Gx ND =Gx ND = ND 0+751+001+251+501+752+002+25

Rock Creek

II - - 8 8 4 4

. !

. ! .

! Rock Creek Upstream . !

.

Upstream ! West 1 . ! Downstream 0#

CR-BCH 0#West 2

Rock Creek Downstream

. ! Center 1 (Sample Lost) Source 0#0# Center 2 (1, 2, and 3) East 2 0# East 1 0#

Columbia River

Flow Direction

Photograph 1 - Grab Sample - Upstream Location Photograph 2 - Photograph 3 - Grab Sample - Downstream Location Photograph 4 - Rock Creek Drainage Near Manhole Grab Sample - Outfall/Source Location

LEGEND .! Surface Water Grab Sample Location Rock Creek $ 0# OSU Passive Diffusion Sample Location FIGURE 3-1 .! Manhole SURFACE WATER SAMPLING LOCATIONS WWTP Effluent Pipeline CITY OF MOSIER 0 100 200 300 400 UNION PACIFIC RAILROAD WASCO COUNTY, OREGON Approximate Boom Location Feet

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\SITE_ASSESSMENT\OSU_SAMPLES.MXD GGEE 10/26/2016 11:45:44 AM

69.3 Rock Creek

. ! *# *# *# *# *#*# CR-NS-West

II - - 8 8 4 4 CR-NS-East CR-OS-Central *# *# *# *# CR-OS-East CR-OS-West

ColumbiaColumbia RiverRiver

0 100 200 300 400 LEGEND Feet SED-RC-UP *# Sediment Sample Location $

*# .! Manhole

. ! WWTP Effluent Pipeline Approximate Boom Location

*#SED-CR-BCH

SED-RC-DN *#

*#SED-CR-OF CR-NS-Central *#

FIGURE 3-2 SEDIMENT SAMPLING LOCATIONS 0 20 40 80 Feet MOSIER, OR - JUNE 3, 2016 DERAILMENT UNION PACIFIC RAILROAD WASCO COUNTY, OREGON

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\SITE_ASSESSMENT\FIGURE4-1_SEDIMENTSAMPLELOCS.MXD GGEE 7/22/2016 9:43:55 AM

*# 3+25

3+00

2+75

3+25 ST ¿

Depth = 5 ft bgs ¿

6/11/2016 ¿ 3+00 ST Dx = ND ¿

2+50 Depth = 5 ft bgs Gx = ND ¿

6/11/2016 "/

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Gx = ND ¿ 3+00 "/¿

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6/11/2016 1+75 ¿

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¿ 2+50 NF "/ 2+50 WW

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¿ 0+75 Gx = ND ¿ ¿ ¿ ¿ ¿ ¿ 2+50 NW ¿ ¿ ¿ Depth = 5 ft bgs ¿ Dx = ND Depth = 18 ft bgs 6/11/2016 Gx = ND 0+50 SW 0+50 0+75 SW Dx = ND "/ 6/10/2016 Depth = 3 ft bgs Depth = 4 ft bgs Gx = ND "/ 2+25 NF Dx = ND 1+50 F Gx = ND 6/11/2016 6/11/2016 1+75 F "/ 2+00 NF Depth = 16 ft bgs Depth = 8 ft bgs 0+25 Dx = ND Dx = ND Depth = 7 ft bgs Depth = 14 ft bgs 6/10/2016 "/ 1+25 F 6/21/2016 Gx = ND Gx = ND 6/21/2016 6/11/2016 Dx = ND "/ Depth = 4 ft bgs Dx = ND "/ Dx = ND Dx = ND Gx = ND 6/21/2016 Gx = ND "/ 0+50 EW Dx = ND "/ Gx = ND Gx = ND "/ 2+50 Depth = 3 ft bgs 0+75 F 1+00 F Gx = ND 0+00 6/9/2016 "/ Depth = 4 ft bgs Depth = 4 ft bgs "/ 1+50 NF "/ 6/11/2016 6/21/2016 Depth = 8 ft bgs 1+75 NF Dx = ND Depth = 7 ft bgs 0+00 EW Gx = ND Dx = ND Dx = ND 6/21/2016 Depth = 3 ft bgs Gx = ND "/ Gx = ND Dx = ND 6/21/2016 6/9/2016 "/ Gx = ND "/ Dx = ND 1+25 NW Dx = ND 0+50 F "/ Gx = ND Depth = 3.5 ft bgs Gx = ND Depth = 4.5 ft bgs 2+25 NW 6/21/2016 6/21/2016 1+50 NW 2+00 NW Depth = 8 ft bgs "/ Dx = ND 0+75 NW 1+00 NW Dx = ND Depth = 3.5 ft bgs Depth = 5 ft bgs "/ 6/10/2016 "/ Depth = 4 ft bgs "/ Gx = ND "/ "/ "/ Gx = ND "/ Depth = 3 ft bgs "/ 6/21/2016 6/10/2016 Dx = ND 0+00 NW 6/11/2016 6/21/2016 Dx = ND Dx = ND Gx = ND Depth = 3 ft bgs Dx = ND 0+50 NW Dx = ND Gx = ND Gx = ND 6/9/2016 Gx = ND Depth = 4 ft bgs Gx = ND Dx = ND Gx = ND 6/21/2016 Dx = ND Gx = ND 0+50 0+75 1+00 68.9 0+00 0+25 1+25 1+50 1+75 2+00 2+25

LEGEND Soil Sample Naming Notes: Notes: "/ Soil Sample Location Sample locations are designated by station numbering Sample results for bottom of excavation shown. Results for $ and position along the station line are identified by the overexcavated samples not shown. Preliminary Excavation Area following notations: ND = nondetect FIGURE 3-3 F = floor (center) mg/kg = milligrams per kilogram Stations NF = north floor Dx = diesel/light crude oil SOIL CONFIRMATION SAMPLES IN Milepost SF = south floor Gx = gasoline EXCAVATION AREA DF = deep floor Bold = detected values Damaged Manhole NW = north wall ft bgs = feet below ground surface NWTPH-DX/GX RESULTS ¿ SW = south wall 0 10 20 30 40 MOSIER, OR - JUNE 3, 2016 DERAILMENT Influent Pipeline WW = west wall UNION PACIFIC RAILROAD EW = east wall WASCO COUNTY, OREGON Feet ST = side trench \\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\SITE_ASSESSMENT\FIGURE7-1_SOIL_DXGX_062416.MXD GGEE 7/22/2016 8:34:04 AM

" /

Pothole-1 Track 8 FL

/ " Pothole-4

Track 9 FL

. ! /

" Track 2 FL

Rock Creek Track 7 NW / Pothole-2 " Track 4 SW Manhole 68.9 GFGF GF Pothole-3 GF GF GFGF GF GF GF GF Track 11 FL Track 3 SW Track 10 NW Track 1 FL Track 6 SW

Track 5 FL 0 15 30 60 Feet $ 0 20 40 80 Feet $

LEGEND "/ Pothole Sample Location Pothole Sample Map Extent GF Mainline Track Sample Location (Upper Left) .!"/"/ .! Manhole "/ WWTP Effluent Pipeline

Track Sample Map Extent (Upper Right) 68.8

68.9 GF GF GFGF GF FIGURE 3-4 GFGF $ POTHOLE AND MAINLINE GFGF GF GF TRACK SAMPLE LOCATIONS 69 0 100 200 300 400 CITY OF MOSIER 0 20 40 80 Feet UNION PACIFIC RAILROAD Feet WASCO COUNTY, OREGON

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MW-7 !U

BS-1 BS-3 !. BS-2 BS-4 !. !. BS-5 !. !.

!U MW-6 !U MW-3 !U !U MW-2 MW-5 !U MW-4 !U MW-1

!U EW-2

¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ !. ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿!U !. ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ EW-1 ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ ¿ !.¿

VICINITY MAP Service Layer Credits: Sources: Esri, HERE, DeLorme, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, LEGEND MapmyIndia, © OpenStreetMap contributors, and the GIS User Community !U Extraction Well !. Manhole !U Monitoring Well WWTP Pipeline !. Biosparge Well Milepost Notes: WWTP = wastewater treatment plant Air Distribution Piping FIGURE 4-1 Site Location Air Injection System (AIS) $ BIOSPARGE SYSTEM LAYOUT 0 40 80 120 CITY OF MOSIER UNION PACIFIC RAILROAD Feet WASCO COUNTY, OREGON

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\SITE_ASSESSMENT\FIGURE4-1_BIOSPARGELAYOUT.MXD GGEE 10/26/2016 11:54:08 AM

Appendix A Spill Report and IC Sampling Plan

SPILL/RELEASE REPORT

1 - GENERAL INFORMATION OERS No. 2016-1305 a. Company/Individual Name: Union Pacific Railroad b. Address: 221 Hodgeman Laramie, WY 82072 c. Company Contact Person: Gary Honeyman d. Phone Number(s): 402-233-1007 e. Specific on-site location of the release (and address if different from above): 1505 Rock Creek Rd., Mosier, Oregon (See Figure 1) Please provide a map of the site showing area(s) where the release occurred, any sample collection locations, location of roads/ditches/surface water bodies, etc.

2 - RELEASE INFORMATION a. Date/Time Release started: 6/3/16 12:15 PM Date/Time stopped: 6/4/16 02:30 b. Release was reported to (specify Date/Time/Name of Person contacted where applicable): ODEQ Kim Van Patten OERS Jim Raymond ODOT Chris Kuenzi Other (describe):______c. Person(s) reporting release: Jeff Dukes/UPRR d. Name, quantity and physical state (gas, liquid, solid or semi-solid) of material(s) released: Bakken crude oil (47,000 gallons) Please attach copies of material safety data sheets (MSDS) for released material(s). e. The release affected: ____Air __X__Groundwater _X__ Surface Water __X__ Soil ____Sediment f. Name and distance to nearest surface water body(s), even if unaffected (include locations of creeks, streams, rivers and ditches that discharge to surface water on maps): Rock Creek (250 feet to the west of spill), Columbia River (612 feet to the north of spill) Has the release reached the surface water identified above?: _X_ Yes ____No Could the release potentially reach the surface water identified above? __X_ Yes ____No Explain: Rock Creek is unaffected. Figure 1 shows the approximate location of sheen observed on the Columbia River on Day 2 of the release. g. Depth to nearest aquifer/groundwater: 23 feet below ground surface Is nearest aquifer/groundwater potable (drinkable)? ____Yes X__ No Has the release reached the nearest aquifer/groundwater? __X__ Yes ___ No Explain: Two extraction wells and four monitoring wells have been installed to provide monitoring data. h. Release or potential release to the air occurred? ____Yes _X___ No Explain:______i. Was there a threat to public safety? __X__ Yes ____No j. Is there potential for future releases? ____Yes __X__ No Explain: Leaking train cars have been removed from the area. k. Describe other effects/impacts from release (emergency evacuation, fish kills, etc.): Residents were evacuated due to fire. l. Describe how the release occurred. Include details such as the release source, cause, contributing weather factors, activities occurring prior to or during the release, dates and times of various activities, first responders involved in containment activities, etc.: Sixteen tanker cars carrying Bakken crude oil derailed releasing oil and catching fire. The derailment sheared off a manhole on a line that directly flows to the Mosier wastewater treatment plant (WWTP). Some oily water entered the line before the opening of the manhole could be plugged. The oily water worked its way through the WWTP and discharged via the buried outfall to the Columbia River. A summary of response activities is provided in Attachment 1. More information will be provided in the Site Assessment Report being prepared by CH2M on behalf of UPRR for submittal in July 2016.

3 - SITE INFORMATION a. Adjacent land uses include (check all that apply and depict on site maps): __X__Residential __X__Commercial ____Light Industrial ___Heavy Industrial ____Agricultural ____Other (describe):______b. What is the population density surrounding the site:_____<500 people______c. Is the site and/or release area secured by fencing or other means? ____Yes X_No d. Soil types (check all that apply): __X__alluvial ____ bedrock ____ clay ____sandy ____silt ____ silty loam ____artificial surface (cement/asphalt/etc.) e. Describe site topography: rolling hills

4 - CLEANUP INFORMATION a. Was site cleanup performed? __X__ Yes ____No If No, explain:______b. Who performed the site cleanup?

Company Name: NRC Environmental Services Clean Harbors Environmental Services Address: 6211 N. Ensign Street 12402 SE Jennifer St., Ste 160 Portland, OR 97217 Clackamas, OR 97015 Cleanup Supervisor: Randy Legler Junior Mendoza Phone Number(s): (503) 283-1150 509-379-5096 c. Has all contamination been removed from the site? ____ Yes _X___No If No, explain: Two Baker tanks of oily water remain onsite, pending final analysis and waste characterization. d. Estimated volume of contaminated soil removed: 2,960 tons e. Estimated volume of contaminated soil left in place:__TBD______f. Was a hazardous waste determination made for cleanup materials? __X_ Yes ____No g. Based on the determination, are the cleanup materials hazardous wastes? ____Yes _X__ No If Yes, list all waste codes: ______h. Was contaminated soil or water disposed of at an off-site location? __X__ Yes ____No If yes, attach copies of receipts/manifests/etc., and provide the following information:

Facility Name: Columbia Ridge Landfill Wasco County Landfill Address: 18177 Cedar Springs Lane 2550 Steele Road Arlington, OR 97812 The Dalles, OR 97058 Phone Number(s): 541-454-2030 541-296-4082

Disposal tickets are provided in Attachment 2. i. Is contaminated soil or water being stored and/or treated on-site? __X__ Yes __ No If yes, please describe the material(s), storage and/or treatment area, and methods utilized (attach additional sheets if necessary): Two Baker tanks of oily water remain onsite, pending final analysis and waste characterization. j. Describe cleanup activities including what actions were taken, dates and times actions were initiated and completed, volumes of contaminated materials that were removed, etc. (attach additional sheets or contractor reports if necessary or more convenient): A summary of response activities is provided in Attachment 1. More information will be provided in the Site Assessment Report being prepared by CH2M on behalf of UPRR for submittal to DEQ in July 2016.

5 - SAMPLING INFORMATION Attach copies of all sample data and indicate locations of sample collection on maps. a. Were samples of contaminated soil collected? __X__ Yes. ____No ____N/A b. Were samples of contaminated water collected? _X___ Yes ____No ____N/A c. Were samples collected to show that all contamination had been removed? __X__ Yes ____No ____N/A d. Describe sampling activities, results and discuss rationale for sampling methods: Soil, surface water and groundwater samples were collected as agreed to with Incident Command. Sample locations are provided on Figure 1. In addition, soil samples were collected from the floor and sidewalls of the excavation. More information will be provided in the Site Assessment Report being prepared by CH2M on behalf of UPRR for submittal to DEQ in July 2016.

6 - SPILL REPORT CHECKLIST

To ensure that you have gathered all the information requested by the Department in this Spill/Release Report, please complete the following checklist:

____ Map(s) of the site showing buildings, roads, surface water bodies, ditches, waterways, point of the release, extent of contamination, areas of excavation and sample collection locations attached.

____ Material Safety Data Sheet (MSDS) for released material(s) attached. Note: an MSDS is not required for motor fuels.

Not applicable.

____ Sampling data/analytical results attached.

To be provided in the Site Assessment Report being prepared by CH2M on behalf of UPRR for submittal to DEQ n July 2016.

____ Receipts/manifests (if any) for disposal of cleanup materials attached.

Attachment 2 provides disposal tickets.

____ Contractor reports (if any) attached.

If you would like to submit your report by e-mail it can be submitted electronically to: [email protected] Columbia River

INTERSTATE 84

Observed Sheen through Outfall

68.6 .!

Manhole and Effluent Pipe

INTERSTATE 84

W e s t L a k e 68.7

Rock Creek 68.8 MW-1 !U MW-2 !U MW-3 68.9 !U MW-4 VICINITY MAP EW-2 !U !U !UEW-1 E a s t L a k e .! 69 Wastewater Treatment Plant Excavation Area

Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, LEGEND AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community Columbia River Proposed Wells Boom Area !U Extraction Well Rock Creek Extent Shown Above !U Downgradient Monitoring Well WWTP Pipeline Source Area - Surface Water WWTP .! Manhole $ FIGURE 1 Milepost Location Map 0 50 100 150 200 CITY OF MOSIER Feet UNION PACIFIC RAILROAD WASCO COUNTY, OREGON

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\FIGURE1_SOURCEAREAS_061716.MXD GGEE 6/17/2016 11:27:35 AM Attachment 1 Summary of Response Actions On June 3, 2016, at 12:20 pm, 16 tanker cars carrying Bakken crude oil derailed, releasing oil, and catching fire near Mosier, Oregon. Initial response efforts included fire department response from 17 agencies; evacuation of local residents; purging and removal of four damaged tanks; track removal and replacement; coordination with the Yakima Nation; clean-out of the City of Mosier’s wastewater treatment plant (WWTP); temporary diversion and containerization of wastewater from the City of Mosier while the WWTP was offline for repairs; transportation of containerized wastewater from the City of Mosier to Hood River WWTP; replacement of WWTP equipment due to fouling; excavation and disposal of impacted soil; numerous multimedia sampling events; and installation and sampling of groundwater monitoring wells A summary of activities performed by each contractor from June 3-17, 2016, is provided below. CH2M HILL (CH2M) is preparing a Site Assessment Report on behalf of Union Pacific Railroad Company (UPRR) for submittal to the Oregon Department of Environmental Quality which will provide more comprehensive information. Clean Harbors Environmental Services • Cleaned out the damaged tank cars • Installed and maintained booms in river during initial response and site restoration activities • Provided boat and operator for boom maintenance, water quality observations, and surface water and sediment sampling • Decontaminated the equipment, piping, and appurtenances associated with the Mosier WWTP • Containerized oil recovered and oil-impacted wastewater from the WWTP in Baker tanks • Provided transportation and disposal of the approximately 247,000 gallons of oil-impacted wastewater to Columbia Ridge Landfill • Provided Baker tanks for temporary containerization of wastewater collected from residents of the City of Mosier while the WWTP was offline for cleaning and repair • Provided daily transportation of the containerized wastewater from the site to Hood River WWTP for treatment while the Mosier WWTP was offline. NRC Environmental Services • Completed test pits to determine horizontal and vertical extent of contamination • Excavated, loaded, and disposed of 2,557 tons of impacted soils at the Wasco Landfill • Graded backfilled soil into the excavation • Jet rodded the effluent line from the WWTP and repaired manhole. • Assisted the City of Mosier’s contractor with repairing the influent line to the WWTP Attachment 2 Soil Tickets

Attachment 2 Water Tickets

Mosier Unit Train Derailment Sampling Plan Sampling Plan Approval Unified Command Signatures

This document is approved by the Unified command

Signatures:

Mosier Unit Train Derailment Spill June 13, 2016 Page 2

Introduction This plan describes the sampling strategy and techniques as well as the analytical methods that will be employed at the site. It consists of soil sampling to support excavation activities, surface water, sediment, and groundwater sampling.

Sampling Objectives: • Characterize the extent and nature of contamination (groundwater, sediment in river channel, surface water, soil) • Support Unified Command decision-making regarding cleanup endpoints • Support excavation operations to determine when cleanup is complete and backfilling can commence • Ensure sampling is repeatable. • Establish monitoring system that will act as a sentinel if petroleum contamination is moving towards the river • Not intended to fingerprint oil or prove that oil in environment matches spilled material. This is being handled by samples already collected.

Safety Special care should be paid to the traffic, physical, and chemical hazardous outlined in the Health and Safety Plan. Environmental Unit staff members should use care entering excavation areas for purposes of collecting samples, observing soil conditions, or conducting field screening. Workers are not permitted within 25 feet of the main rail line to the south of the site. Steep slopes, rocks, and vegetation (blackberries) are a safety hazards to workers in the creek. Proper PPE (person protective equipment) must be worn at all times by all workers on- site.

Sample Names The Environmental Unit (EU) established select sample points on and near the incident site to evaluate surface water (SW), groundwater (GW), and sediment (SED). Confirmation sampling of the soil at the edges of the excavation will also be done (SL). Samples will be named in a descriptive fashion.

Surface Water: Surface Water samples shall be named using the following conventions: SW-Location Name for example “SW-Site One” (see below for sample locations)

Mosier Unit Train Derailment Spill June 13, 2016 Page 3

Groundwater: Groundwater samples from monitoring wells will be named using the following convention: Monitoring Well Number, for example “MW-1”

Sediment: Sediment samples shall be named using the following conventions: Sediment samples will be collected from the Columbia River and the mouth of Rock Creek. Columbia River samples will be designated “CR” and Rock Creek will be designated “SED-RC- UP/Down” for upstream and downstream samples. Columbia River sample locations will be designated for near shore “NS” and offshore “OS”. For example a surface water sample collected in the Columbia River, near shore at the eastern location will be designated “CR-NS- East. (See below for sample locations)

Soil: Soil confirmation samples collected in the main spill area will be collected and named using a station number convention that incorporates either coordinates by a benchmark system, or latitude and longitude, so as to be reproducible. Confirmation soil samples will be collected at 25 foot intervals on the floor and sidewalls of the excavation. All soil sample names will be preceded by the designated station number. For example, a confirmation soil sample collected from station 1+75 on the floor of the excavation will be designated 1+75FL followed by the sample depth.

Field Screening to Support Excavation During excavation activities field screening will consist of photo ionization detector (PID) monitoring, PID monitoring with bag samples, and visual and olfactory indications. Field screening may be used for confirmation of certain areas in the excavation that need to be excavated and backfilled quickly, for example to stabilize sidewall slopes. No backfill will be placed (in a cleaned area) without explicit approval or clearance by an agency EU representative.

PID data will be collected and recorded, with locations determined using GPS coordinates, by the environmental unit member who is monitoring the excavation. This data may be placed on a map at the conclusion of each day’s field activities by the person who collected the data.

Sample Management This plan describes multiple parallel sampling efforts of multiple media and will involve many samples. Sample tracking is important to the environmental unit and the response as a whole to keep a current understanding of conditions and to make sound cleanup decisions.

Mosier Unit Train Derailment Spill June 13, 2016 Page 4

Until further notice, Nathan Williams with CH2MHill will be responsible for ensuring that proper sample tracking occurs. These actions consist of:

1. Collecting chain of custody documentation for all samples leaving the site and placing them in a binder, which is stored in the Environmental Unit (as well as a copy for the documentation unit). 2. Ensuring that all samples collected by all samplers make the once daily shuttles to Test America. 3. Maintaining copies of all preliminary and final sample results in the sample binder in the environmental unit (all sample results are also to be provided to the documentation unit). The results will also be provided to the EU Leader(s) electronically as soon as they are received. In addition DEQ will be listed on all chain of custody documentation as a recipient of the analytical results, including email copy of the laboratory report to [email protected] and [email protected].

Soil Confirmation Sampling Confirmation samples will generally be collected from the edges of the excavation with the following frequency: • Representative samples will be collected based on field indications to adequately define any remaining crude oil in sidewall or floor samples; or • Samples will be collected every 25 linear feet from the sidewalls; and • Samples will be collected every 25 feet from the floor of the excavation. • Sampling requirements may vary based on field conditions at the discretion of ODEQ. • Samples will be collected under proper chain of custody procedures and immediately placed on ice into a cooler.

Refer to the Excavation Management Plan, dated June 8, 2016 for additional details on sample protocol.

Analytes • Gasoline range petroleum hydrocarbons (NWTPH-Gx) • Diesel and oil range petroleum hydrocarbons (NWTPH-Dx) • Volatile Organic Compounds (VOCs by Method 8260) • Polynuclear aromatic hydrocarbons (PAHs by Method 8270-SIM)

Approximately 10% of all soil samples will analyzed for volatile petroleum hydrocarbons (VPH) and extractable petroleum hydrocarbons (EPH). ODEQ will determine which samples will selected for VPH and EPH analyses.

Method 5035 will be used to collect soil samples analyzed for VOCs.

Mosier Unit Train Derailment Spill June 13, 2016 Page 5

Soil confirmation samples collected in the main spill area will be collected and named using a station number convention that incorporates either coordinates by a benchmark system, or latitude and longitude, so as to be reproducible. All soil sample names will be preceded by the designated station number. For example, a confirmation soil sample collected from station 1+75 on the floor of the excavation will be designated 1+75FL followed by the sample depth.

Surface Water Sampling Grab Samples Initially, twice daily grab samples of the Columbia River and Rock Creek will be collected. Grab samples are intended to characterize the water column, and therefore should not collect sheen. Sampling frequency will be re-evaluated after two days of data have been evaluated by the environmental unit. Changes to the sample frequency will be documented in an addendum to this document. The samples will be collected from the following locations, and can likely be taken by wading into the shallows. The location of each site will be marked on the bank with a flag indicating the sample location name. A total of three sampling locations are located in the Columbia River (Upstream, Source, and Downstream) and two locations in Rock Creek (Downstream and Upstream).

Site 1: Upstream of the incident Site 2: Mouth of Rock Creek, where Rock Creek meets the Columbia River (2 locations) Site 3: Wastewater treatment plant discharge pipe outlet, taken from a boat Site 4: 10 meters downstream of the mouth of rock creek, 2 meters from shore.

The sample locations are marked on the attached Figure 1.

Analytes • Gasoline range petroleum hydrocarbons (NWTPH-Gx) • Diesel and oil range petroleum hydrocarbons (NWTPH-Dx) • Volatile Organic Compounds (VOCs by Method 8260) • Polynuclear aromatic hydrocarbons (PAHs by Method 8270-SIM)

Site 2 may be moved to the closest location to the last manhole of the sewer effluent pipe as the pipe heads into the Columbia. This manhole as well as the local groundwater within several lateral feet of the manhole was impacted by oil.

Additional samples may be added to surface water just above the sediment to approximate pore water.

Additional surface water samples will be collected at the wetland area north of the rail when surface water is observed during fall/winter 2016.

Mosier Unit Train Derailment Spill June 13, 2016 Page 6

Installation of staff gauge in the Columbia River.

Passive Diffusion Bag Samples CH2MHILL, ODEQ, and NOAA are currently working on an approach and developing data quality objectives for collection of water in the Columbia River using passive diffusion bag samplers or other agreed upon sampling devices. This work will be conducted under a separate sampling and analysis plan.

Sediment Sampling Sediment samples will be collected at locations designated on Figure 2. Sediment samples will be collected at ten designated locations and include:

Site 1: Upstream of the incident (2 locations) Site 2: Rock Creek Area (4 locations) Site 3: Wastewater pipe outlet (2 locations) Site 3: 10 meters downstream of the mouth of Rock Creek (2 locations)

Sediment samples will be collected via boat using a ponar-type sampler. All sediment locations will be located and logged using a hand-held GPS unit.

Analytes • Gasoline range petroleum hydrocarbons (NWTPH-Gx) • Diesel and oil range petroleum hydrocarbons (NWTPH-Dx) • Volatile Organic Compounds (VOCs by Method 8260) • Polynuclear aromatic hydrocarbons (PAHs by Method 8270-SIM)

Groundwater Sampling The objective of the groundwater sampling is to determine if contaminated groundwater or free product are flowing through the subsurface into the wetland or the Columbia River.

A total of two extraction wells and up to four monitoring wells will be installed at the site. The two extraction wells designated “EW” will be installed in the spill area. The four monitoring wells designated “MW” will be installed on UPRR property north of the existing mainline track. Location of the monitoring wells are shown on Figure 1. The need for additional monitoring wells will be evaluated based on sampling results. Eight rounds of groundwater samples will be collected on a weekly basis. Sampling frequency will be re-evaluated based on sampling results.

Drilling wells in the area north of the tracks will require some amount of small tree removal. A track-mounted drill rig will be used in order to limit ground disturbance. The City’s botanist and a Yakama Nation monitor walked the area north of the rails to determine the path to take for the drill rig on June 10, 2016, The City botanist will flag plants that cannot be removed or

Mosier Unit Train Derailment Spill June 13, 2016 Page 7

damaged prior to drilling. All work in this area will be cleared by the City of Mosier, Oregon State Parks, tribal representatives, and other appropriate key stakeholders. Work will be conducted in accordance with the cultural resources plan and the Restoration Plan

When approved by ODEQ, monitoring wells will be abandoned in accordance with Water Resources Department regulations. All well decommissioning will follow the same protocols for well installation. The City botanist and the Yakima Nation will be notified of any work in this area prior to well abandonment.

This section may be updated depending on completion of the Restoration Plan.

Two extraction wells are planned for the excavation/source area and will consist of 4 inch diameter constructed of PVC well screen and riser pipe. The wells will be completed as flush mount wells in a well vault approved for vehicular traffic. All wells will be logged and constructed per CH2MHILL’s SOP for well drilling and construction. The SOP follows all WRD requirements. The four monitoring wells located north of the spill site will be constructed using 2-inch PVC well screen and river pipe and will be completed using flush-mount surface monuments.

Analytes • Gasoline range petroleum hydrocarbons (NWTPH-Gx) • Diesel and oil range petroleum hydrocarbons (NWTPH-Dx) • Volatile Organic Compounds (VOCs by Method 8260) • Polynuclear aromatic hydrocarbons (PAHs by Method 8270-SIM)

All monitoring wells will be surveyed to NGVD coordinates.

Turn Around Time (TAT) All water samples will initially be run on a 24 hour turn-around time. As the cleanup progresses EU will recommend moving to a standard TAT. This change will be made as an addendum to this plan.

Soil samples will be analyzed with a 24-hour TAT if the decisions based on the data are time critical.

Stand Alone Sampling Efforts

Manway Sampling A sample will be collected from the most riverward manway on the sewage system. The objective is to document the success of the jet-rodding efforts. Since we may not have sample results by the time the treatment plant is in operation again, an agency EU member will observe the sampling effort and look for field indications of impact, such as sheen or odor, at

Mosier Unit Train Derailment Spill June 13, 2016 Page 8 the time the sample is collected. If there are field indications of impact additional cleanup efforts will be needed. Upon completion of jet rodding the section between the cleanup plant and the last manway, the plug will be placed in the landward pipe in the manway and the plug will be pulled from the pipe on the riverward side of the manway. If the water has field indications of impact water will be pumped until it is clean. Once clean water is observed in the manway, it will be sampled for the standard river water analytes described above.

Groundwater and/or soil samples will be collected from two potholes near the sewer manhole and tow potholes upstream of the manhole. Samples will be analyzed for the following:

• Gasoline range petroleum hydrocarbons (NWTPH-Gx) • Diesel and oil range petroleum hydrocarbons (NWTPH-Dx) • Volatile Organic Compounds (VOCs by Method 8260) • Polynuclear aromatic hydrocarbons (PAHs by Method 8270-SIM)

City Water System An EU member will accompany City of Mosier staff to sample the domestic water supply at a point close to the spill location. The sample will be analyzed for VOCs by EPA Method 8260.

Wetland Surface Water Sampling Surface water and/or pore water samples will be collected from the wetland located approximately 75 feet north of MW-4. The wetland is flooded as river stage rises during certain times of the year. Exact location of the sampling stations will be determined once surface water is observed. A sampling and analysis plan will be developed as an addendum to this sampling plan.

Addendums Additional sampling, outside the scope of this sampling plan, may be required based on the results of the initial cleanup and sampling activities. Additional sampling will be described in future addendums, which may include:

• Additional monitoring well installation • Wetland surface water sampling • Quality Assurance/Quality Control Plan

Columbia River

INTERSTATE 84

68.6 .!

INTERSTATE 84

W e s t 68.7 L a k e

Rock Creek 68.8 MW-1 !U MW-2 !U MW-3 68.9 !U MW-4 EW-2 !U !U !UEW-1 E a s t L a k e .!

Wastewater 69 Treatment Plant

Excavation Area 69.1

VICINITY MAP Service Layer Credits: Sources: Esri, HERE, DeLorme, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, LEGEND MapmyIndia, © OpenStreetMap contributors, and the GIS User Community Proposed Wells Boom Area !U Extraction Well Rock Creek FIGURE 1 !U Downgradient Monitoring Well WWTP Pipeline APPROXIMATE WELL Soil Excavation Area .! Manhole $ LOCATIONS and SURFACE Site Location Surface Water Sample Location Milepost WATER SAMPLE LOCATIONS 0 60 120 180 240 CITY OF MOSIER WWTP UNION PACIFIC RAILROAD Feet WASCO COUNTY, OREGON

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\FIGURE2_PROPOSEDMONITORINGWELLS_V2.MXD GGEE 6/17/2016 12:19:39 PM

69.3 Rock Creek

. ! *# CR-OS-East *# *# *# *# *#*# CR-NS-West

II - - 8 8 4 4 CR-NS-East CR-OS-Central *# *# *# CR-OS-West

ColumbiaColumbia RiverRiver

0 100 200 300 400 LEGEND Feet SED-RC-UP *# Sediment Sample Location $

*# .! Manhole

. ! WWTP Effluent Pipeline Approximate Boom Location

SED-CR-BCH *#

SED-RC-DN *#

CR-NS-Central *# SED-CR-OF *# FIGURE 2 MOSIER SEDIMENT SAMPLING LOCATIONS CITY OF MOSIER 0 20 40 80 Feet UNION PACIFIC RAILROAD WASCO COUNTY, OREGON

\\PDXFPP01\PROJ\UNIONPACIFICRAILROAD\SPILLRESPONSE\UPRR MOSIER OR\GIS\MAPFILES\PRESENTATION\FIGURE8_SEDIMENTSAMPLELOCS.MXD GGEE 7/14/2016 8:44:35 AM

*#

Appendix B Representative Site Photographs

Appendix B Representative Site Photographs Union Pacific Railroad Company Mosier Release Site Assessment Report

B‐2: Boom deployment in Columbia River – June 3, 2016

B‐1: Derailed cars and fire (from Highway 30 bridge) – June 3, 2016

B‐3: Derailed cars near Rock Creek Road – June 4, 2016 B‐4: Hard and soft boom deployment in Columbia River – June 4, 2016

1

Appendix B Representative Site Photographs Union Pacific Railroad Company Mosier Release Site Assessment Report

B‐6: Columbia River surface water sampling at upstream location (via boat) – June 7, 2016

B‐5: Replacement of track (view from Highway 30 bridge) – June 5, 2016

B‐8: Columbia River surface water sampling at downstream location (via boat) – B‐7: Columbia River surface water sampling near outfall (via boat) – June 7, 2016 June 7, 2016

2

Appendix B Representative Site Photographs Union Pacific Railroad Company Mosier Release Site Assessment Report

B‐9: Columbia River surface water sampling at upstream location (via shore) – B‐10: Columbia River surface water sampling near outfall (via shore) – June June 8, 2016 8, 2016

B‐11: Columbia River surface water sampling at downstream location (via shore) B‐12: Removing damaged railcars – June 8, 2016 – June 8, 2016

3

Appendix B Representative Site Photographs Union Pacific Railroad Company Mosier Release Site Assessment Report

B‐13: Excavation of Soils on South Side of Tracks B‐14:: Extraction Well Drilling

B‐15: Installation of new manhole to WWTP B‐16: Monitoring well installation

4

Appendix C OSU Passive Sampling Device SAP and Final Report

SAP for Mosier Train Derailment, prepared July 7, 2016.

The SAP is organized as follows:

 Section 1: Summary of Passive Sampling Approach  Section 2: PRC Loading and LDPE PSD Preparation  Section 3: Field Deployment and Retrieval Methods  Section 4: Sample Identification and Handling Procedures  Section 5: Post-Processing and Sampling of PSDs  Section 6: Field QC Samples  Section 7: Laboratory Analysis and Quality Control  Section 8: Data Calculations  Section 9: Schedule and Reporting

Supporting materials are provided in associated, tables, figures, and appendices as cited throughout.

1.0 Summary of Passive Sampling Approach

Eight LDPE water-samplers will be deployed at six sites as indicated on the associated map. Two sampler arrays will be deployed at the approximate location of the initiating point of the oil sheen with one array containing triplicate water cages and designated Source 1 a, b or c and Source 2. Two sites 0.6 km upstream of the source of the oil sheen will be sampled with single samplers to provide river-specific background analyte levels and designated Upstream one and Upstream 2 and two sites approximately 0.1 km downstream will also be sampled with individual samplers, and designated Downstream one and Downstream 2.

As discussed in associated conference calls and follow-up E-mails, the samplers are equipped with inert low-density polyethylene (LDPE) tubing, which essentially acts as a carbon sink such that PAHs sorb to the LDPE. Performance reference compounds (PRCs) will be impregnated into the LDPE as described in OSU’s Standard Operating Procedures (SOPs) for passive sampling provided in the Appendix. Pictures of a water sampler are provided in Figure 1.

Our intent is that passive samplers will be deployed by field staff from shore in shallow water (sampling strategies requiring boat deployment/retrieval will incur additional costs). Field deployment is further discussed in Sections 3.0 and 3.1.

2.0 PRC Loading and LDPE PSD Preparation

The passive sampling LDPE and DGT media will be prepared at the OSU laboratory before deployment to make PSDs. The following OSU SOPs, provided in the Appendix, describe the procedures for preparation of LDPE, infusion of PRCs onto the LDPE, and fabricating the PSDs before deployment.  SOP 2120.06 – Cleaning of LDPE for Fabrication of PSD  SOP 2131.00 – Drying of the Pre-Cleaned Organic PSDs

 SOP 2121.02 – Preparation of PE PSDs for Use in Environmental Sampling Equipment

All LDPE used on this project will be prepared in the same batch to ensure comparability between sample results. Because all samples will be prepared in the same manner and at the same time and PSDs are loaded with a known volume and concentration of PRC fortification solution, tracking of time-zero concentrations by PSD is not necessary. The PRCs used on this project will be fluorene-d10, pyrene-d10, and benzo(b)fluoranthene-d12. The LDPE PSDs will be used for analysis of PAHs, as described in Section 7.1.

3.0 Field Deployment and Retrieval Methods

At the beginning of field work, a pre-sampling meeting will be held with all field staff to (1) discuss health and safety requirements; and (2) review sampling objectives and procedures as outlined in this SAP.

The OSU Aquatic Field Sampling Methods for PSDs SOP 100.03 (Appendix) describes the techniques for loading the PSDs into the surface water cages, and the deployment and retrieval techniques that should be followed in the field. Temperature loggers (“tidbits”) will be included to allow accurate calculation of free-water concentrations. A summary of project specific deployment and retrieval techniques is provided in this section and should be reviewed and followed by the field team to ensure data of sufficient quality and consistency are collected to meet project objectives.

Passive samplers will be deployed from shore or shallow water by OSU personnel. GPS positioning data will be recorded at each deployment site. The actual sample coordinates will be recorded in the field logbook. Because of relatively shallow sampling sites (typically 3 to 4 feet), water cages will be set at depths of 2-feet from the bottom and sampling site depths estimated.

On-site inspection and on-going deployment ensure likely availability of indicated target sites. Should unanticipated changes in conditions occur which generate hazardous conditions (deep water and/or high wind-driven swells) at any site, deployment may be re-evaluated and target sites moved to ensure team safety. Any site changes will still be selected to provide sufficient data to make upstream/source/downstream comparisons.

For shallow water stations where samples can be collected by field staff from shore:  Field staff should be equipped with waders and the appropriate personal protective equipment (PPE).).  All in-water field staff will work in pairs (at least), using the buddy system to complete all tasks.  On-shore support staff will maintain areas for preparing and processing samples on-shore will be set up so that as much of the work can be conducted from shore vs. in the water.  Actual sample location will be collected after the sampler is installed.

3.1 Field Placement of Passive Samplers The prepared LDPE PSDs (see Section 2.0) will be transported to the Site by OSU staff in coolers equipped with “blue ice.”

Before deployment, the LDPE PSDs will be inserted into the surface water cage as described in OSU Aquatic Field Sampling Methods for PSDs SOP 100.3. All personnel handling the PSDs should wear nitrile gloves and care should be taken to minimize any contact with the LDPE PSDs inside the samplers.

Surface Water Deployment:  Place the PSD on the deployment hardware.  Place the deployment hardware into the deployment cage and secure.  Attach cage(s) to deployment gear, ensuring that the gear is adjusted for the appropriate water depth and so that the top of the sampler is approximately 24 inches above the mudline. The weight of the anchor and buoyancy of the support buoy should be appropriate for deployment conditions. If a top buoy is used as a visual marker, ensure sufficient slack line to account for changes in water depth.  Submerge entire apparatus into the water and verify that deployment is correct before releasing the top buoy or rope.

3.2 Field Retrieval of Passive Samplers Following the deployment period the field team will re-mobilize to the Site to retrieve the passive samplers. The top buoy should allow for visual relocation of the deployment gear. Teams will remove the water samplers and transport to a nearby onshore field team. Once onshore, OSU field personnel will remove the PSDs from the protective sampling cage, rinse them with water from the Site to remove sediment or biofouling (if necessary), and store the LDPE PSDs in labeled, clean, sealed jars for transport to the OSU laboratory within 24 hours of retrieval.

4.0 Sample Identification and Handling Procedures

This section describes procedures for sample identification and chain of custody that should be used for field activities. These procedures ensure sample quality is maintained during collection, transportation, storage, and analysis.

4.1 Sample Identification Assign each sample a unique identification (ID) number describing the sample location. Record the sample number on a waterproof sample label and affix the label to the sample jar. To aid in data management, the field team should use consistent sample location numbers as described below. Each sample ID will consist of abbreviations reflecting the following six components:

1. Site Identification: MTD = Mosier train derailment 2. Sample Matrix: SW = surface water exposure, Sample Media: PE = polyethylene (i.e., LDPE) 3. Sample Month: e.g., 10 = Month of sample retrieval (e.g., October) 4. Sample Year: e.g., 15 = Year of collection (e.g., 2015)

5. Sample Station Number: An alphanumeric code indicating direction (East, West or Source) and sample number.

For example, MTDSWPE0716-E1 would be used to describe the surface water exposed LDPE sample collected in July 2016 at station East 1. Triplicate source samples will be appended with S1a, S1b and S1c respectively (ie MTDSWPE0716-S1a).

4.2 Sample Labels Use sample labels to identify samples collected in the field. Once recovered, the PSDs will be placed in laboratory-cleaned amber bottles and a sample label will be firmly attached to the sample container and covered with clear packaging tape for protection. Information on the sample label should be sufficient to enable cross-reference with the field bench sheets and contain, at a minimum, the following information:  Sample identification  Date and time of collection

4.3 Sample Custody OSU personnel will maintain custody of the samples for the duration of fieldwork, transport, and processing and will follow standard custody procedures to trace the possession and handling of a sample from collection to completion of all required analyses. Chain of custody procedures and forms, if required, will adhere to the requirements set forth in the OSU Chain of Custody for QAPP SOP 2021.01 (Appendix K).

4.4 Sample Handling and Packaging All PSDs will be transported between the field and the OSU laboratory by OSU field staff and thus shipping of the samples or additional transfer of custody is not anticipated. PSDs will be stored in clean amber containers in coolers containing “blue ice” to maintain refrigeration before arrival at the laboratory. Coolers will be packaged carefully to avoid breakage or contamination. Given that inter-agency custody transfers are not anticipated, custody seals will not be used.

4.5 Field Logbooks and Data Forms Field deployment/recovery bench sheets and data forms are necessary to document daily activities and observations. Documentation should be sufficient to enable participants to accurately and objectively reconstruct project events. Entries should be made in waterproof ink, dated, and signed.

4.6 Photographs Photographs will be taken to document field activities. Photos will be downloaded into a photo log file, and kept with the electronic project files.

5.0 Post-Processing and Sampling of PSDs Upon arrival at the OSU laboratory, samples will be logged in, and the LDPE PSDs will be frozen until extraction. The procedures for processing the LDPE PSDs before analysis are described in OSU’s passive sampling SOPs and summarized below by PSD media.

5.1 LDPE Cleaning, Sub-sampling, and Extraction The LDPE PSDs will be cleaned to remove biofouling, water, and other potential analytical interferences. If frozen, samples will be brought back to room temperature before cleaning. Cleaning will be conducted under a solvent hood at the OSU laboratory following the procedures outlined in the OSU Cleaning Field Deployed Polyethylene PSDs SOP 108.01This procedure includes submersing the PSDs sequentially in three different solvents. Once cleaned, the PSDs are cut into pieces using clean scissors and stored in amber jars until extraction. The OSU chemist will fill out a bench sheet documenting the cleaning process and will include a post- deployment cleaning blank with each batch of samples.

The method for extracting organic compounds (i.e., PAHs and PCP) from the PSDs by use of a two-step hexane dialysis is described in the OSU Extraction of Organic Compounds from Polyethylene PSDs SOP 406.02 (Appendix K). Once dialysis is completed, the extracts are transferred and concentrated in hexanes. The OSU chemist will fill out a bench/QC summary sheet documenting the extraction process and will include all field and/or laboratory QC samples to ensure batch extraction quality.

6.0 Field QC Samples Field Triplicate (FT) The FT is a triplicate sample collected at a target sample location (i.e., three samples collected independently at a sampling location during a single act of sampling). The purpose is to evaluate the precision of sampling procedures. FT samples will be collected at one of the two source sample sites. Additionally, trip, construction and field blanks will generated and analyzed.

7.0 Laboratory Analyses and Quality Control 7.1 Chemical Analyses Chemical analysis of the surface water samples will be completed by the OSU laboratory as described in the following SOPs, provided in the Appendix:

 SOP 418.00 – Determination of Parent and Methyl Substituted Polynuclear Aromatic Hydrocarbons (PAHs) using Gas Chromatography Tandem Mass Spectrometry (GC- MS/MS)

For the purpose of this project, the 62 PAHs will be reported as listed in the associated SOP. Additionally, limits of detection (LODs) and limits of quantitation (LOQs) are provided within the SOP.

7.2 Laboratory QA/QC Procedures Laboratory QA/QC will be maintained through the use of standard EPA methods and other accepted methods and standard analytical procedures for the target analytes. The method-specific and other analytical and laboratory QC procedures and protocols followed are detailed in the laboratory’s method-specific SOPs. These procedures incorporate the collection and analysis of the following laboratory QA/QC components: • Internal QC samples • Continuing calibration verification (CCVs)

• (Extraction blanks) • Matrix spikes (MS) and duplicates (DUP) samples • Laboratory blank spikes Reagent blanks • Calibration check samples

8.0 Calculations of Water Concentrations from PSD Results The methods for estimating porewater and surface water concentrations from concentrations measured in PSDs, are described for LDPE extraction results.

8.1 LDPE Calculations In order to assess an analyte’s in situ LDPE-water exchange kinetics performance reference compounds are added. Labelled compounds will be used ensuring that the PRCs do not occur in the environment. By determining the depletion of PRC compounds during the deployment period, the sampling rate of target constituents in LDPE can be estimated and used in conjunction with literature-based partitioning coefficients to calculate the sampler water partitioning coefficient. Water concentrations can then be calculated based on the equations provided in Section II.C of the OSU Calculation of PAH Water Concentrations Derived from PSD SOP 407.01.

OSU personnel will perform all of the calculations necessary to convert the raw LDPE results and present the final surface water and porewater results in their report (Section 4.8.2).

8.0 Schedule, Reporting and Data Sharing

8.1 Schedule To be determined

8.2 Reporting A preliminary report, including field placement and retrieval methods, sample preparation and transport, analytical methods, data analysis, interpretation of results, and conclusions will be prepared by OSU and submitted approximately 45 days after completion of fieldwork.

8.3 Data Sharing Water concentration data will be available to the FSES program at Oregon State for inclusion into scientific publication and dissertations. Data values will be compared to those obtained from additional technologies currently co-deployed at Mosier, and will be used with appropriate acknowledgement of primary data ownership by Union Pacific.

F16-24 – Final report 1 August 15, 2016

Mosier OR, Train Derailment August 16, 2016

Prepared for Union Pacific Railroad/CH2M

Prepared by

FOOD SAFETY & ENVIRONMENTAL STEWARDSHIP LABORATORY Peter Hoffman, Assistant Director.

ENVIRONMENTAL AND MOLECULAR TOXICOLOGY 1007 AGRICULTURE AND LIFE SCIENCES BUILDING OREGON STATE UNIVERSITY CORVALLIS, OR 97331-7301

Contact: Dr. Kim A. Anderson, Director

phone: 541-737-8501, fax: 541-737-0497 email: [email protected]

Page 1 of 4

F16-24 – Final report 2 August 15, 2016

Client: Michael Niemit - CH2M/Union Pacific Railroad (UPRR) FSES Case #: F16-24

Date Sampled: 6/24/2016 Sample Type(s): LDPE PSDs Report Status: Final Samples Delivered By: FSES collection team Condition Samples Received: on ice Submitter: FSES staff Report Date: 8/17/2016

Executive summary

The Food Safety & Environmental Stewardship Program (FSES) provided sampling and analytical services at Columbia River sites associated with the June 3rd UPRR oil train derailment and fire, with oil contamination of the near-adjacent Columbia river. The analytical work and sampling plan was developed with consultation from UPRR representatives (CH2M) and personnel representing the Oregon Department of Environmental Quality (ODEQ), Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA).

Under this agreement FSES provided the following services:  Standard operating procedures (SOPs) for laboratory operations, analytical methods and field methods for finalization of the Mosier train derailment Sampling and Analysis Plan (SAP)  Manufactured low-density polyethlyene (LDPE) passive sampling devices (PSDs) with performance reference compound (PRC) infusion  Field sampling equipment rental for: o 6 locations with surface water samplers, two each at upstream (Mosier East 1 and 2), wastewater treatment outfall (Mosier Mid 1 and 2) and downstream (Mosier West 1 and 2). o Mosier Mid 2 location sampled with triplicate, co-located samplers.  Subsequent extraction of PSDs and measurement of 61 polycyclic aromatic hydrocarbons (PAHs).  Analytical report (this document).

Page 2 of 4

F16-24 – Final report 3 August 15, 2016

Sampling and Analytical Plan

A sampling and analytical plan (SAP) containing standard operating procedures (SOPs) covering the preparation, manufacture, pre- and post-deployment cleaning, field deployment and recovery, extraction and quantitative determination of parent and alkyl- substituted polycyclic aromatic hydrocarbons were provided and methodology for calculation of freely dissolved water concentrations of organic compounds were provided on July 7, 2016 (SAP attached).

Field Operations

After on-site examination, six field locations were chosen for sampler deployment. Two were significantly upstream to prevent wind-driven sampler contamination with surface sheen oil (East 1 and 2), two at the wastewater treatment outfall site, the apparent source of the oil sheen (Center 1 and 2) and two samplers downstream of the outfall sight (West 1 and 2). Triplicate samplers were deployed at Center 2. Deployment of PSDs occurred on June 24th and samplers were retrieved July 8th. During retrieval, sampler Center 1 was found entangled in beachside debris apparently deposited there by extreme wind-driven wave action during the week preceding retrieval. The three remaining Center 2 samplers were undisturbed.

Sampler locations (latitude and longitude) were as follows (refer to picture for identity):

latitude longitude East 1 45.68658 -121.39647 East 2 45.68645 -121.39673 *Center 1 Sample lost Sample lost Center 2 (1, 2, and 3) 45.68742 -121.4044

West 1 45.68729 -121.40589

West 2 45.68737 -121.40601 *the second sampler placed at the center location was lost likely due to extreme wind and wave action.

Page 3 of 4

F16-24 – Final report 4 August 15, 2016

LDPE PSD Processing and Analysis

Upon arrival in the laboratory on July 8th, LDPE PSDs were stored at -20 °C and logged into the FSES laboratory information management system (LIMS) within 24 hours. PSDs were post-deployment cleaned and extracted on July 12, 2016. PSDs were analyzed for PAHs and data analyzed between July 12 and August 12, 2016.

PAH results

All PAH analysis achieved our desired data quality objectives (DQOs) as specified in the SAP. Summarized certificate of analysis (COA) attached.

Questions: If you have any additional questions, please call the Food Safety and Environmental Stewardship Laboratory Director at 541-737-8501.

DIRECTOR: ______DATE:______Kim A. Anderson, PhD

Page 4 of 4

SAP for Mosier Train Derailment, prepared July 7, 2016.

The SAP is organized as follows:

 Section 1: Summary of Passive Sampling Approach  Section 2: PRC Loading and LDPE PSD Preparation  Section 3: Field Deployment and Retrieval Methods  Section 4: Sample Identification and Handling Procedures  Section 5: Post-Processing and Sampling of PSDs  Section 6: Field QC Samples  Section 7: Laboratory Analysis and Quality Control  Section 8: Data Calculations  Section 9: Schedule and Reporting

Supporting materials are provided in associated, tables, figures, and appendices as cited throughout.

1.0 Summary of Passive Sampling Approach

Eight LDPE water-samplers will be deployed at six sites as indicated on the associated map. Two sampler arrays will be deployed at the approximate location of the initiating point of the oil sheen with one array containing triplicate water cages and designated Source 1 a, b or c and Source 2. Two sites 0.6 km upstream of the source of the oil sheen will be sampled with single samplers to provide river-specific background analyte levels and designated Upstream one and Upstream 2 and two sites approximately 0.1 km downstream will also be sampled with individual samplers, and designated Downstream one and Downstream 2.

As discussed in associated conference calls and follow-up E-mails, the samplers are equipped with inert low-density polyethylene (LDPE) tubing, which essentially acts as a carbon sink such that PAHs sorb to the LDPE. Performance reference compounds (PRCs) will be impregnated into the LDPE as described in OSU’s Standard Operating Procedures (SOPs) for passive sampling provided in the Appendix. Pictures of a water sampler are provided in Figure 1.

Our intent is that passive samplers will be deployed by field staff from shore in shallow water (sampling strategies requiring boat deployment/retrieval will incur additional costs). Field deployment is further discussed in Sections 3.0 and 3.1.

2.0 PRC Loading and LDPE PSD Preparation

The passive sampling LDPE and DGT media will be prepared at the OSU laboratory before deployment to make PSDs. The following OSU SOPs, provided in the Appendix, describe the procedures for preparation of LDPE, infusion of PRCs onto the LDPE, and fabricating the PSDs before deployment.  SOP 2120.06 – Cleaning of LDPE for Fabrication of PSD  SOP 2131.00 – Drying of the Pre-Cleaned Organic PSDs

 SOP 2121.02 – Preparation of PE PSDs for Use in Environmental Sampling Equipment

All LDPE used on this project will be prepared in the same batch to ensure comparability between sample results. Because all samples will be prepared in the same manner and at the same time and PSDs are loaded with a known volume and concentration of PRC fortification solution, tracking of time-zero concentrations by PSD is not necessary. The PRCs used on this project will be fluorene-d10, pyrene-d10, and benzo(b)fluoranthene-d12. The LDPE PSDs will be used for analysis of PAHs, as described in Section 7.1.

3.0 Field Deployment and Retrieval Methods

At the beginning of field work, a pre-sampling meeting will be held with all field staff to (1) discuss health and safety requirements; and (2) review sampling objectives and procedures as outlined in this SAP.

The OSU Aquatic Field Sampling Methods for PSDs SOP 100.03 (Appendix) describes the techniques for loading the PSDs into the surface water cages, and the deployment and retrieval techniques that should be followed in the field. Temperature loggers (“tidbits”) will be included to allow accurate calculation of free-water concentrations. A summary of project specific deployment and retrieval techniques is provided in this section and should be reviewed and followed by the field team to ensure data of sufficient quality and consistency are collected to meet project objectives.

Passive samplers will be deployed from shore or shallow water by OSU personnel. GPS positioning data will be recorded at each deployment site. The actual sample coordinates will be recorded in the field logbook. Because of relatively shallow sampling sites (typically 3 to 4 feet), water cages will be set at depths of 2-feet from the bottom and sampling site depths estimated.

On-site inspection and on-going deployment ensure likely availability of indicated target sites. Should unanticipated changes in conditions occur which generate hazardous conditions (deep water and/or high wind-driven swells) at any site, deployment may be re-evaluated and target sites moved to ensure team safety. Any site changes will still be selected to provide sufficient data to make upstream/source/downstream comparisons.

For shallow water stations where samples can be collected by field staff from shore:  Field staff should be equipped with waders and the appropriate personal protective equipment (PPE).).  All in-water field staff will work in pairs (at least), using the buddy system to complete all tasks.  On-shore support staff will maintain areas for preparing and processing samples on-shore will be set up so that as much of the work can be conducted from shore vs. in the water.  Actual sample location will be collected after the sampler is installed.

3.1 Field Placement of Passive Samplers The prepared LDPE PSDs (see Section 2.0) will be transported to the Site by OSU staff in coolers equipped with “blue ice.”

Before deployment, the LDPE PSDs will be inserted into the surface water cage as described in OSU Aquatic Field Sampling Methods for PSDs SOP 100.3. All personnel handling the PSDs should wear nitrile gloves and care should be taken to minimize any contact with the LDPE PSDs inside the samplers.

Surface Water Deployment:  Place the PSD on the deployment hardware.  Place the deployment hardware into the deployment cage and secure.  Attach cage(s) to deployment gear, ensuring that the gear is adjusted for the appropriate water depth and so that the top of the sampler is approximately 24 inches above the mudline. The weight of the anchor and buoyancy of the support buoy should be appropriate for deployment conditions. If a top buoy is used as a visual marker, ensure sufficient slack line to account for changes in water depth.  Submerge entire apparatus into the water and verify that deployment is correct before releasing the top buoy or rope.

3.2 Field Retrieval of Passive Samplers Following the deployment period the field team will re-mobilize to the Site to retrieve the passive samplers. The top buoy should allow for visual relocation of the deployment gear. Teams will remove the water samplers and transport to a nearby onshore field team. Once onshore, OSU field personnel will remove the PSDs from the protective sampling cage, rinse them with water from the Site to remove sediment or biofouling (if necessary), and store the LDPE PSDs in labeled, clean, sealed jars for transport to the OSU laboratory within 24 hours of retrieval.

4.0 Sample Identification and Handling Procedures

This section describes procedures for sample identification and chain of custody that should be used for field activities. These procedures ensure sample quality is maintained during collection, transportation, storage, and analysis.

4.1 Sample Identification Assign each sample a unique identification (ID) number describing the sample location. Record the sample number on a waterproof sample label and affix the label to the sample jar. To aid in data management, the field team should use consistent sample location numbers as described below. Each sample ID will consist of abbreviations reflecting the following six components:

1. Site Identification: MTD = Mosier train derailment 2. Sample Matrix: SW = surface water exposure, Sample Media: PE = polyethylene (i.e., LDPE) 3. Sample Month: e.g., 10 = Month of sample retrieval (e.g., October) 4. Sample Year: e.g., 15 = Year of collection (e.g., 2015)

5. Sample Station Number: An alphanumeric code indicating direction (East, West or Source) and sample number.

For example, MTDSWPE0716-E1 would be used to describe the surface water exposed LDPE sample collected in July 2016 at station East 1. Triplicate source samples will be appended with S1a, S1b and S1c respectively (ie MTDSWPE0716-S1a).

4.2 Sample Labels Use sample labels to identify samples collected in the field. Once recovered, the PSDs will be placed in laboratory-cleaned amber bottles and a sample label will be firmly attached to the sample container and covered with clear packaging tape for protection. Information on the sample label should be sufficient to enable cross-reference with the field bench sheets and contain, at a minimum, the following information:  Sample identification  Date and time of collection

4.3 Sample Custody OSU personnel will maintain custody of the samples for the duration of fieldwork, transport, and processing and will follow standard custody procedures to trace the possession and handling of a sample from collection to completion of all required analyses. Chain of custody procedures and forms, if required, will adhere to the requirements set forth in the OSU Chain of Custody for QAPP SOP 2021.01 (Appendix K).

4.4 Sample Handling and Packaging All PSDs will be transported between the field and the OSU laboratory by OSU field staff and thus shipping of the samples or additional transfer of custody is not anticipated. PSDs will be stored in clean amber containers in coolers containing “blue ice” to maintain refrigeration before arrival at the laboratory. Coolers will be packaged carefully to avoid breakage or contamination. Given that inter-agency custody transfers are not anticipated, custody seals will not be used.

4.5 Field Logbooks and Data Forms Field deployment/recovery bench sheets and data forms are necessary to document daily activities and observations. Documentation should be sufficient to enable participants to accurately and objectively reconstruct project events. Entries should be made in waterproof ink, dated, and signed.

4.6 Photographs Photographs will be taken to document field activities. Photos will be downloaded into a photo log file, and kept with the electronic project files.

5.0 Post-Processing and Sampling of PSDs Upon arrival at the OSU laboratory, samples will be logged in, and the LDPE PSDs will be frozen until extraction. The procedures for processing the LDPE PSDs before analysis are described in OSU’s passive sampling SOPs and summarized below by PSD media.

5.1 LDPE Cleaning, Sub-sampling, and Extraction The LDPE PSDs will be cleaned to remove biofouling, water, and other potential analytical interferences. If frozen, samples will be brought back to room temperature before cleaning. Cleaning will be conducted under a solvent hood at the OSU laboratory following the procedures outlined in the OSU Cleaning Field Deployed Polyethylene PSDs SOP 108.01This procedure includes submersing the PSDs sequentially in three different solvents. Once cleaned, the PSDs are cut into pieces using clean scissors and stored in amber jars until extraction. The OSU chemist will fill out a bench sheet documenting the cleaning process and will include a post- deployment cleaning blank with each batch of samples.

The method for extracting organic compounds (i.e., PAHs and PCP) from the PSDs by use of a two-step hexane dialysis is described in the OSU Extraction of Organic Compounds from Polyethylene PSDs SOP 406.02 (Appendix K). Once dialysis is completed, the extracts are transferred and concentrated in hexanes. The OSU chemist will fill out a bench/QC summary sheet documenting the extraction process and will include all field and/or laboratory QC samples to ensure batch extraction quality.

6.0 Field QC Samples Field Triplicate (FT) The FT is a triplicate sample collected at a target sample location (i.e., three samples collected independently at a sampling location during a single act of sampling). The purpose is to evaluate the precision of sampling procedures. FT samples will be collected at one of the two source sample sites. Additionally, trip, construction and field blanks will generated and analyzed.

7.0 Laboratory Analyses and Quality Control 7.1 Chemical Analyses Chemical analysis of the surface water samples will be completed by the OSU laboratory as described in the following SOPs, provided in the Appendix:

 SOP 418.00 – Determination of Parent and Methyl Substituted Polynuclear Aromatic Hydrocarbons (PAHs) using Gas Chromatography Tandem Mass Spectrometry (GC- MS/MS)

For the purpose of this project, the 62 PAHs will be reported as listed in the associated SOP. Additionally, limits of detection (LODs) and limits of quantitation (LOQs) are provided within the SOP.

7.2 Laboratory QA/QC Procedures Laboratory QA/QC will be maintained through the use of standard EPA methods and other accepted methods and standard analytical procedures for the target analytes. The method-specific and other analytical and laboratory QC procedures and protocols followed are detailed in the laboratory’s method-specific SOPs. These procedures incorporate the collection and analysis of the following laboratory QA/QC components: • Internal QC samples • Continuing calibration verification (CCVs)

• (Extraction blanks) • Matrix spikes (MS) and duplicates (DUP) samples • Laboratory blank spikes Reagent blanks • Calibration check samples

8.0 Calculations of Water Concentrations from PSD Results The methods for estimating porewater and surface water concentrations from concentrations measured in PSDs, are described for LDPE extraction results.

8.1 LDPE Calculations In order to assess an analyte’s in situ LDPE-water exchange kinetics performance reference compounds are added. Labelled compounds will be used ensuring that the PRCs do not occur in the environment. By determining the depletion of PRC compounds during the deployment period, the sampling rate of target constituents in LDPE can be estimated and used in conjunction with literature-based partitioning coefficients to calculate the sampler water partitioning coefficient. Water concentrations can then be calculated based on the equations provided in Section II.C of the OSU Calculation of PAH Water Concentrations Derived from PSD SOP 407.01.

OSU personnel will perform all of the calculations necessary to convert the raw LDPE results and present the final surface water and porewater results in their report (Section 4.8.2).

8.0 Schedule, Reporting and Data Sharing

8.1 Schedule To be determined

8.2 Reporting A preliminary report, including field placement and retrieval methods, sample preparation and transport, analytical methods, data analysis, interpretation of results, and conclusions will be prepared by OSU and submitted approximately 45 days after completion of fieldwork.

8.3 Data Sharing Water concentration data will be available to the FSES program at Oregon State for inclusion into scientific publication and dissertations. Data values will be compared to those obtained from additional technologies currently co-deployed at Mosier, and will be used with appropriate acknowledgement of primary data ownership by Union Pacific.

SOP 2120.06 Page 1 of 3 Cleaning of Low Density Polyethylene for Fabrication of PSD

Food Safety and Environmental Stewardship Program Oregon State University Standard Operating Procedure

Scope This document describes the procedure for fabricating PSD from low density polyethylene (LDPE) tubing received from Brentwood Plastic Inc. Cleaning of the LDPE removes chromatographic interferences and other contaminants and must be performed prior to preparation of PSD for any experimental uses. Cleaning includes solvent washes, vacuum drying and storage of PSD.

Contributors: S.E. Allan

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Equipment and Apparatus A. Additive-free low-density polyethylene lay-flat tubing, approximately 75-95 µm thick x 2.54 cm wide – Barefoot® from Brentwood Plastics Inc. B. Large, wide mouth amber glass jars (1000 mL) with lid C. Shaker table in warm room or floor incubator with shaker D. Continuous Temperature Logger (optional) E. Measuring tool to 1.08 meter F. Two flex frames with aluminum rods G. Two clamps H. Scissors

II. Reagents A. Hexanes – Fisher Scientific Optima Grade or better B. Acetone – Fisher Scientific Optima Grade or better

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2120.06 Page 2 of 3 III. Procedure A. LDPE pre-cleaning in preparation to fabricate PSD 1. Assign a sequential lot number for the PSD batch and mark on the bench sheet. A log book for PSD pre-cleaning is maintained and can be referenced for lot numbers. 2. Clean working surface by cleaning thoroughly with detergent and water then acetone and hexanes. 3. Wear nitrile gloves at all times while handling tubing. Minimize exposure to environment. 4. Cut 108 cm lengths of lay-flat tubing. 5. Place 8 pre-cut PSDs, or < 9 m of tubing, in a 1 L clean amber jar. 6. Add warm hexanes approximately 100 mL of hexanes for 1 m of tubing. a) Warm hexanes to approximately 26° C in a water bath prior to use b) Assure the tubing moves freely and hexanes contact all surfaces. 7. Place jar(s) on shaker table in warm room or floor incubator. a) The temperature during pre-cleaning should be maintained at 26 ± 4° C. Set shaker table at 60 ± 15 RPM b) Record the temperature of the warm room or incubator immediately prior to each exchange. OPTIONAL: use a temperature logger or other recorder. 8. Three hexanes extractions occur over a total of approximately 72 hour extraction time. Each exchange occurs approximately every 24 hrs. Note: All exchanges should occur in a hood. a) Pour used hexanes into a solvent waste container while maintaining PSD in the jar. b) Rinse tubing and inside of jar with a small amount of hexanes and discard hexane waste. c) Refill jar with warm hexanes as before.

B. PSD Drying and Storage 1. Prepare workspace in fume hood as described in A.2-3 above 2. Remove hexanes from tubing by squeezing towards open end. 3. Dry PSDs according to SOP 2131 Drying of PSDs. 4. After drying, store tubing in clean jar or can. Label with PE PSD batch lot number.

IV. Quality Control A. In recognition of advances that are occurring in separations, the analyst is permitted certain options to improve the separations or lower the cost. Each time such a modification is made to the method, the analyst is required to document any alterations to the procedure on bench sheets during the analysis. For permanent changes, the standard operating procedures should be formally updated with new validations.

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2120.06 Page 3 of 3 B. Place a minimum of 2 PSDs from each lot in a clean container and archived in the freezer. Individual projects will often have specific data quality objectives (DQOs). C. Extract a minimum of 1 blank PSD from each lot using at least one of the PE PSD methods, (e.g. SOP 406) to check for background. Analysis and results will be documented on the PSD preparation bench sheet D. For instance, the Superfund PAH project DQO is a 500 pg D12-Perylene spike on the cleaned PSD requires a 2:1 (+/- 20%) peak to background noise.

V. Documentation Requirements A. Check http://fses.oregonstate.edu/sop-toc for current version of all required documents. B. A bench sheet is required for PE PSD pre-cleaning a) 2120-LDPE-pre-cleaning-for-PSD-Fabrication.xls

VI. Safety and Health A. Please consult Material Safety Data Sheet (MSDS) information on reagents. Personnel performing this method will observe all appropriate Oregon State University laboratory safety procedures. All procedures involving hexanes should be carried out under a chemical hood. Always use personal protective equipment. Use protective gloves (nitrile) while handling all PE PSDs. Dispose of solvents into solvent waste containers for disposal by Environmental Health and Safety Department, OSU campus.

VII. Validation A. Not applicable

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2120 Cleaning of LDPE for Fabrication of PSD

PSD Lot Number:

PSD Fabrication Start Date: LDPE Roll #:

Number and Approx. vol. Hexanes 1st solvent 2nd solvent Roll PSD- volume of jars Approx. PSDs hexanes per jar addition start Rinse before exchange start Rinse before exchange start remove Transfer PSD to (amber) per jar (m) (mL) time exchange time exchange time hexanes drying keg Drying start time Drying end time

Initials

Date

Temperature - Temperature - Temperature - Incubator Shaker Table 60 start of 1st start of 2nd start of Hexanes Location ± 15 RPM solvent solvent removal (°C) exchange (°C) exchange (°C) QC Check - Analysis of Blank PSD

Dialysis Date

Analysis Date Initials

Date Instrument Temperature Logger: YES / NO Method Notes: Reagent Company and Grade Lot Number

Hexanes

LFT Supplier Type of plastic Date Received Brentwood Plastics Inc. Additive-free LDPE

PSD Storage Location Archive Sample Location

Notes: Chemist Review Signature Date

FSES Director Review Signature Date

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2131.00 Page 1 of 4 Drying of Pre-cleaned Organic Passive Sampling Devices (PSDs)

Scope This document describes the procedure for drying pre-cleaned organic passive sampling devices (PSDs). This document is applicable to LFT (made of LDPE) and silicone polymer based PSDs.

Contributors: S.E. Allan, K.A. Hobbie, K. Kamerud

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Equipment and Apparatus A. Nitrile gloves B. Two (2) polyurethane foam plugs (PUFs) – cleaned using SOP 2130. C. A large cylindrical glass column/ tube such as a Soxhlet extractor with fittings to accommodate PUFs with a tight seal, or a large metal chamber such as a Cornelius keg. D. Flow meter capable of measuring 1 to 10 L/min at room temp E. Tygon vacuum tubing, applicable fittings for drying chamber and vacuum supply F. Appropriate clean PSD storage container (Examples: glass jar, paint can, PTFE bag)

II. Reagents A. Hexanes – Rinse Grade or better B. Acetone – Rinse Grade or better C. Ethyl Acetate – Rinse Grade or better D. Methanol – Rinse Grade or better

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2131.00 Page 2 of 4

III. Procedure: Either a glass or metal chamber can be used in this drying method, use appropriate steps below based on apparatus. Use protective gloves (nitrile) while handling all PSDs.

A. Glass Chamber PSD Drying Method NOTE – Glass Chamber should be cleaned according to SOP 2110 1. Place PSDs into the large cylindrical column or Soxhlet extractor tube. 2. Stack two clean PUFs in the top of the tube or funnel and attach the male fitting to the condenser end of the column or tube (See Figure 1). Note: multiple tapered fittings may be needed for a proper fit. 3. Block the flask end (bottom) of the column or tube with a stopper modified to fit the vacuum tubing. Attach the other end of the Tygon tubing to the flow meter. Attach the exit end of the flow meter to the house vacuum line. 4. Turn on vacuum and adjust flow to approximately 3.6 to 5.3 cc/min meters (approx 1 L/min, or 2.5,6 on Brooks E/C meter SN 7004-39338/4). 5. Leave apparatus under vacuum until organic solvent is removed from PSDs, ~48 to 72 hours at room temperature, depending on the amount of tubing. 6. After drying, store PSDs in a clean container. Label with PSD batch lot number.

B. Metal Chamber Pre-cleaning Method 1. For LFT use: a) Rinse inside of keg with acetone, including metal tubing. Repeat two more times with acetone, and three times with hexane. b) Attach keg to vacuum with tygon tubing. c) Rinse the inside of the metal tubing by creating a small pool of acetone in the bottom of the keg. Recap the keg, and turn on the vacuum until all solvent is removed. Repeat two more times with acetone and three times with hexane. d) Remove the o-ring from the keg lid. e) Rinse the keg lid three times with acetone and hexane. f) Using a Kimwipe clean o-ring with acetone and hexane. g) Replace o-ring in keg lid. h) Before use clean the outside of the keg using a Kimwipe with acetone and hexane. 2. For Silicone use: a) See Metal Chamber pre-cleaning for LFT (III.B.1) b) Use ethyl acetate in place of acetone and methanol in place of hexane.

C. Metal Chamber PSD Drying Method 1. Place PSDs into drying keg and close lid. 2. Stack two large or four small clean PUFs into the filter cartridge. 3. Attach the filter cartridge to the keg input using Tygon tubing. 4. Attach the flow meter to the keg output using Tygon tubing. Attach the exit end of the flow meter to the house vacuum line.

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2131.00 Page 3 of 4 5. Turn on vacuum and adjust flow to approximately 3.6 to 5.3 cc/min (or approx 1 L/min, or 2.5,6 on Brooks E/C meter SN 7004-39338/4). 6. Leave apparatus under vacuum until all organic solvent is removed from PSDs, ~48 to 72 hours at room temperature, depending on the amount of tubing. 7. After drying, store PSDs in clean container. Label with PSD batch lot number.

IV. Quality Control A. See appropriate PSD pre-cleaning SOP for applicable Quality Control requirements

V. Documentation Requirements A. Check http://fses.oregonstate.edu/sop-toc for current version of all required documents. 1. See PSD pre-cleaning method SOP for required documentation

VI. Safety and Health A. Please consult Material Safety Data Sheet (MSDS) information on reagents. Personnel performing this method will observe all appropriate Oregon State University laboratory safety procedures. All procedures involving hexanes should be carried out under a chemical hood. Always use personal protective equipment. Use protective gloves (nitrile) while handling all LFTs. Dispose of solvents into solvent waste containers for disposal by Environmental Health and Safety Department, OSU campus.

VII. Validation A. Not applicable

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2131.00 Page 4 of 4 Figure 1. Example Glass Drying chamber - LFT drying. Soxhlet extractor tube attached to PUF cylinder (top) and flow meter (bottom). Note: two PUFs in male fitting connecting to female Soxhlet piece, and stopper connected to male Soxhlet piece and tygon tubing.

tygon tubing

male to female fitting LFT PUFs flow metere

Figure 2. Example Metal Drying Chamber

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2121.02 Page 1 of 3 Title Preparation of PE PSDs for Use in Environmental Sampling Equipment

Scope This document describes the procedure for preparation of polyethylene (PE) passive sampling devices PSDs for use on spiders and other environmental sampling equipment. Fortification of PE PSDs with Performance Reference Compounds (PRCs) is also described. PRC Fortification is necessary for determination of site specific analyte uptake rates in field deployed PSDs.

Contributors: S.E Allan, G. Sower

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Equipment and Apparatus Note: Clean all glassware and containers for use in organic chemistries (see SOP 2110- Laboratory Container Cleaning procedure). A. Heat sealer, TEW Electric Impulse Sealer TISH-100 – or equivalent B. Appropriate storage container, examples: wide mouth amber glass jars or PTFE clip and seal bags C. 100 µL pipetman – or equivalent D. Measuring tool to 1 meter or equivalent (for un-cut PSD) E. Two flex frames with aluminum rods – or equivalent (for un-cut PSD) F. Two c-clamps – or equivalent (for un-cut PSD) G. Scissors (for un-cut PSD) H. Pre-cleaned PSD (See SOP 2120)

II. Reagents A. Hexanes – Fisher Scientific Optima Grade – or better B. Acetone – Fisher Scientific Optima Grade – or better

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2121.02 Page 2 of 3 III. Standards A. Performance Reference Compound standard fortification solution. See SOP 2240 for standard preparation, labeling, storage and expiration.

IV. Procedure A. Preparation of work station 1. Table surface, sealer, flex-frames, clamps and scissors must be solvent cleaned (two rinses of acetone, followed by two rinses of hexanes) before use. 2. Set up the flex-frame with aluminum pegs and c-clamps 99 cm apart (for un-cut PSD) B. Preparation of PSD for assembly on spiders 1. Clean nitrile gloves should be worn at all times during PSD preparation. Minimize exposure to environment and light. 2. Heat-seal a 4 cm circumference loop on one end of the tubing using flex frames. 3. If PSD was not pre-cut, measure and cut the PSD before proceeding to the next step. 4. At this stage, include PRC fortification if needed. See Section IV.C below. 5. Force air out of the tube by running the tube from the sealed to open end through fingers. 6. Heat-seal a 4 cm circumference loop on the other end of the tubing. 7. The total length of the PSD is approximately 99 to 100 cm after sealing both ends. 8. Store completed PSD and label container with number and fortification yes/no. Note: For cage deployment in the field, five or ten PSD are commonly stored together.

C. Fortification of PSDs 1. PSD PRC fortification solution must be prepared by a chemist in accordance with the needs of the project. a) The chemist will indicate the volume of solution that should be added to each tube. 2. Carry out fortification just before step #5 in section IV.B. a) Open the unsealed end of the PSD and open the tube by running fingers down the tube seam toward end. b) Insert the pipette tip into the tube opening and add the fortification to the tube. 3. Complete the steps 5-8 in section IV.B.

V. Quality Control A. Each preparation batch will include a single lab preparation blank, which will remain open to the environment for the time-frame of the PSD batch construction. B. Record the PSD lot number and the fortification solution information on the construction bench sheet.

VI. Documentation Requirements A. Check http://fses.oregonstate.edu/sop-toc for current version of all required documents. 1. Bench sheet for PSD construction.

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2121.02 Page 3 of 3 VII. Safety and Health A. Please consult Material Safety Data Sheet (MSDS) information on reagents. Personnel performing this method will adhere to Oregon State University Chemical Hygiene Plan and applicable FSES safety SOPs. B. Always use personal protective equipment. C. Use protective gloves (nitrile) while handling PSDs. D. Dispose of solvents into solvent waste containers for disposal by Environmental Health and Safety Department, OSU campus.

VIII. Validation A. Not applicable

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2121 Benchsheet PE Passive Sampling Device Construction

Project: Date: Participants: Check For Completion

1 Retrieve SOP 2121 for reference

2 Verify quantitiy of PSD tubing needed:

Total PSDs Required PRC Fortified Unfortified

PSD used for construction LOT #:

3 Bring spiking solution to room temperature

4 Plug in heat sealer

5 Verify pipette:

Pipette volume: Pipette serial number:

7 Clean prep table and all relevany equipment with acetone and hexanes

8 Test the length of the first PSD constructed on a deployment spider frame

9 Construct lab preparation blank and hang in construction area

10 Construct all remaining PSDs

Start Time: End Time:

PRC Solution FSES ID Volume Expiration Date

Notes:

Chemist Review Signature Date

FSES Director Review Signature Date

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 100.03 Page 1 of 5

Aquatic Field Sampling Methods for Passive Sampling Devices Food Safety and Environmental Stewardship Program Oregon State University Standard Operating Procedure

Scope This method describes the techniques for deploying and retrieving organic and inorganic passive sampling devices (PSD) in water and sediment pore water. Deployment gear options for oceanic, riverine and lentic systems are explained. Deployment gear and hardware cleaning is described.

Contributors: S.E. Allan, G. Sower, L.B. Paulik

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Equipment and Apparatus A. Passive Sampling Devices (PSD) such as polyethylene, silicone, or DGT prepared for deployment (as per applicable SOP 2120, 208) B. Amber jars or sealable Teflon bags C. Top buoys, support buoys D. Steel cables E. Adjustable rigging (lock-down bolts, U-bolts) F. Ropes G. Anchors H. Deployment cages or probes, with mounting and closure hardware

II. Equipment and Apparatus Gear Clean-up at End of Field Season A. Pressure washer B. Steel brushes C. Scrub pad D. Oven capable of holding the cages and maintaining ~350 oC.

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II. Reagents A. HCl, reagent grade for 2 N HCl Bath B. 18 M Ω*cm water

III. Field Deployment (Figure 1) Specific projects may have unique data quality objectives and field methods that criteria may be used, and will take precedent for those samples. During deployment and retrieval, take precautions to minimize PSD exposure to the air and prevent contact with unclean surfaces. Always wear gloves when handling PSDs. A. Water column deployment 1. Cable gear can be used in any system where suspension of the PSDs in the water column is desired and water movement will not displace the rigging. Gear should be adjusted for appropriate water depths and cage placement depending on the project a) The weight of the anchor and buoyancy of the support buoy should be appropriate for the deployment conditions. b) A top buoy, may be used to serve as a visual marker, can be attached to the support buoy. Allow plenty of slack line to account for changes in water depth. 2. Alternatively, cages can be suspended from or attached to permanent structures. 3. Deployment of PSDs in water column a) Place PSD on deployment hardware. b) Place deployment hardware in the deployment cage and secure. c) Attach cage(s) to deployment gear. d) Submerge entire apparatus into water and verify that deployment is correct before releasing the top buoy or rope. B. Sediment porewater deployment 1. When selecting deployment locations, keep in mind that you must be able to retrieve the probe at the end of the deployment. Changing tides, etc., necessitate careful selection of deployment locations. 2. It is suggested to attach the the probe to something immobile onshore, using metal cable or equivalent or to the water/air PSD gear. This reduces the risk of loss or theft. 3. Deployment of PSDs in porewater. (See Figure 1 & 2.) a) Place PSD on deployment hardware (probe insert). b) Place deployment hardware in the deployment probe and secure. c) Submerge probe into sediment, with only the cylindrical top in the water column. For soil deployments or in tidal flats the top portion of the probe may be in the air column. Attach probe(s) to shore for added security if needed. IV. Field Retrieval A. Locate sampling gear and remove from water/sediment. B. Remove PSDs from the protective cage/probe and deployment hardware. 1. Organic PSDs can be cleaned with water from the sampling site to remove sediment or biofouling if necessary. 2. DGTs can be rinsed with 18 M Ω*cm water to remove biofouling in field if necessary. C. Store PSDs in appropriate labeled container for transport.

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V. Field Re-deployment A. Clean deployment gear to remove biofouling and sediment B. Inspect deployment gear and hardware for damage or excessive ware and replace or repair as needed. C. Deploy PSDs as described in section III.C.

VI. Cleaning Deployment Gear at End of Field Season A. Cleaning buoys and ropes 1. Spray with the pressure washer 2. Air-dry before storage 3. Inspect gear for damage or ware and repair or replace as needed B. Cleaning deployment hardware when necessary if the pressure washer is not sufficient. 1. Soak deployment hardware in 2 N HCl for at least 5 minutes. 2. Remove hardware from acid bath and wash with the pressure washer. 3. Scrub hardware until no debris remains 4. Rinse in DI water. 5. Reassemble deployment hardware, air-dry, then bake at ~350 oC for 12 hours. 6. Store the hardware in bags or clean containers. Note the date and clean status. C. All other deployment gear and hardware (clips, springs etc.) can be cleaned according to SOP 2110 and stored in bags or clean containers.

VII. Quality Control A. Each field batch should include a trip blank and field blank.

VIII. Documentation Requirements A. Check http://fses.oregonstate.edu/sop-toc for current version of all required documents. 1. A completed field collection sheet is required for all field deployments 2. A completed field collection sheet is required for all field retrievals

IX. Safety and Health A. Please consult Material Safety Data Sheet (MSDS) information on reagents. Personnel performing this method will adhere to Oregon State University Chemical Hygiene Plan and applicable FSES safety SOPs. Closed toed shoes should be worn on boats, and when using the pressure washer. Life jackets should always be worn on boats. Request and adhere to boat operator’s Health and Safety Plan. Other safety gear may be applicable when in the field.

X. References A. Sower, G.J. and K.A. Anderson, Spatial and Temporal Variation of Freely Dissolved Polycyclic Aromatic Hydrocarbons in an Urban River Undergoing Superfund Remediation. Environmental Science & Technology, 2008. 42(24): p. 9065-9071

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XI. Validation A. Not applicable

Figure 1: Example aquatic system PSD deployment set-up includes top buoy attached by rope to support buoy, steel cable, adjusting rigging, anchor, PSD cage deployed at 1 to 10 ft from sediment bottom, and sediment probes attached to anchor.

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 100.03 Page 5 of 5

Figure 2: Sediment probe insert/PSD configuration for porewater PSD deployment.

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 100 PSD Deployment Benchsheet

Deployment Date:

Project Number Project Name

Collecting Agency Collector Name (print and sign)

Site Information Site Name Site Location Water Body Type (Optional)

Latitude:

Site Description (optional): Longitude:

GLOVES ON Deployment PSD Fortification Type Load PSD into Sampler Initials & Date Start Time Sample Name (ID) PSD type (Circle one) Environmental Media (Circle one) (Circle one) (check) Notes: PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

Environmental Conditions (optional) Field QC Temp. Logger S/N QC Type Site Description (optional) Check Water Depth Field Blank Other: Trip Blank All

Chemist Review Signature Date

Director Review Signature Date

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 100 PSD Retrieval Benchsheet

Retrieval Date: Deployment Date: Project Number Project Name Total Deployment Time:

Collecting Agency Collector Name (print and sign)

Site Information Site Name Site Location Water Body Type Latitude: (optional): Site Description (optional): Longitude:

GLOVES ON ‐ Retrieve Samplers, Remove PSDs and Deploy. End PSD type Environmental Media PSD Fortification Type store in labeled container Time Initials & Sample Name (ID) (Circle one) (Circle one) (Circle one) (check) Date Notes: PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA

PE / Si / DGT Air/Water/Sed. Bioassay / PRC Fortified / NA Environmental Conditions (optional) Field QC Temp. Logger S/N QC Type Site Description (optional) Check Water Depth Field Blank Other: Trip Blank All

Chemist Review Signature Date Director Review Signature Date

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2021.01 Page 1 of 2

Title Chain of Custody for QAPP

Scope To ensure proper documentation of samples received with chain-of-custody documentation as designated for the FSES Laboratory Quality Assurance Program Plan.

Contributors: K.A. Anderson

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

This SOP was created to meet the FSES Laboratory Quality Assurance Program Plan (QAPP) project needs. SOP 2020, filed under GLP Hold, should be used in cases when adherence to strict Good Laboratory Practice (GLP) is required.

I. Documentation practices at FSES Laboratory are guided by a QAPP. Proper chain of custody for a QAPP refers to documentation of sample possession from collection, sample receipt, sample preparation, analysis and reporting, and disposition. This sample chronological history provides integrity to sample collection, identification, shipment, analysis, and reporting of results. Chain of custody procedures require the following:

A. Sample receipt is documented with signatures of the person relinquishing the sample and the person receiving the samples. B. Storage of the sample is documented with initials of the person placing the sample in storage.

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 2021.01 Page 2 of 2

C. A secured storage area is used with limited access to only defined staff. D. Sample archival and disposal is documented.

II. When FSES staff are not involved in the collection of samples, the starting point for active sample accountability and traceability is typically sample receipt which includes the hand-off (shipping documentation or signature) from courier to FSES. Samples may be delivered by U.S. mail, FEDEX, UPS, bus, and/or freezer truck. Sample conditions vary (i.e., frozen, cooled, ambient temperature, sealed, unsealed, intact, broken, leaking, decaying). Sample documentation may not be complete by sample collector (eg., documentation describing sampling methods, date sampled, sample identification, description of sample, sample size, shipment information, desired analysis, storage conditions, client contact information, and reporting parameters). All such circumstances (when provided) should be documented upon sample receipt as they may have significant bearing on the reliability and quality of the analytical result. All sample submissions and receipt information are logged into the FSES Sample Log-in Book or LIMS and a case file is generated which serves as a systematic and dependable receptacle for documentation. Signature of person(s) relinquishing samples may not always be possible when samples are not hand delivered or are dropped off. Indicate NA (not available) and date/initial. See attached example FSES chain of custody.

III. Intra-laboratory chain of custody for regulated studies is documented with sample processing and analysis bench sheets. These documents record sample handling, subsampling, methodology, date and personnel performing extraction steps, lot number, manufacturer, and grade of extraction reagents, serial number and manufacturer of pipettes and analytical balances, sample extract storage (location, conditions) and date of instrumental analysis. When a method or procedure has been developed for specific sampling processing and analysis, bench sheets and forms are available under the respective FSES standard operating procedures (SOPs).

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version Oregon State University Food Safety & Environmental Stewardship Program Page ____ of ____ FSES Case # 1007 Agriculture & Life Sciences Bldg, Corvallis, OR 97331-7301, 541-737-1781, FAX 541-737-0497 Date Rec. TESTS REQUESTED OTHER INFORMATION Name Would you like your samples returned? Reporting Requirements Agency / Company YES NO Address ___e-mail Results Key City State ZIP ___Verbal Results RT = Room Temperature, R = Refrigerated, F = Frozen, Ambr = Phone ( ) FAX ( ) Email ___FAX Results Amber Jar

Solvent Preser- LIMS ID # (If Sample Submitter Sample ID Sample Type vation Units Remarks TBD Applicabl Amount (FSES use only) Used e) LCMS - oxy-PAHs GCMS PAHs + alkylated PAHs GCMS oxy-PAHs Retardants Flame - GC-MS GC-MS PCBs screen contaminant multi-organic AMDIS GC-ECD - Pesticides

CHAIN OF CUSTODY: Signature Time/Date Signature Time/Date

Relinquished By: Relinquished By:

Received By: Received By:

Storage Requirements: Storage Location: Location Signature

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 108.01 Page 1 of 3

Title: Cleaning Field Deployed Polyethylene Passive Sampling Devices (PSDs)

Scope This method describes the method for cleaning polyethylene passive sampling devices that have been deployed in the environment. Cleaning is intended to remove potential analytic interferences prior to extraction of organic compounds from the LFT. Procedures for cleaning air and water deployed LFT are described.

Contributors: S.E. Allan

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Equipment and Apparatus Note: All jars and equipment are cleaned for use in organic chemistries (see SOP 2110- Laboratory Container Cleaning procedure) A. Large, wide-mouth glass jars (for cleaning) B. Amber, wide-mouth glass jars (for storage and later dialysis) C. Scissors

II. Reagents A. Hexanes, EMD OmniSolv grade, or equivalent B. Acetone, EMD OmniSolv grade, or equivalent C. Isopropanol, EMD reagent grade, or equivalent D. 1 N HCL solution, Fisher, reagent grade, or equivalent E. 18 Mcm water, EASYpure UV, Barnstead, or equivalent

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 108.01 Page 2 of 3

III. Water Deployed polyethylene PSD cleaning Note: All cleaning should be carried out in a solvent hood. Care should be taken to minimize PSD contamination including exposure to air and gloves should be worn at all times when handling PSDs. A. Polyethylene PSDs are cleaned individually to remove debris, biofouling, water and other potential analytical interferences. B. Cleaning solutions should be prepared in large glass jars and replaced as needed or between every sample. PSDs are sequentially cleaned in three different solvents described below: 1. If PSD are excessively dirty, perform an initial cleaning with 18 Mcm water. 2. Cut the tubing lengthwise prior to cleaning. 3. Submerge PSD in 1N HCL a) Clean tubing thoroughly using fingers or cleaning tools as necessary to remove debris and biofouling, remove then, 4. Submerge PSD in 18 Mcm water a) Remove as much water as possible by passing tubing through fingers remove then, 5. Quickly submerge PSD sequentially in two isopropanol baths a) Remove excess solvent by passing tubing through fingers 6. Dispose of isopropanol, rinse glassware and replace isopropanol baths between samples to prevent carry over.

II. Air Deployed polyethylene PSD Cleaning A. PSDs are cleaned individually to remove particulate matter and moisture. 1. Quickly submerge each PSD in isopropanol then remove excess solvent by passing tubing through fingers.

III. PSD Cutting and Storage A. Cleaned PSDs are cut into pieces using clean scissors 1. Rinse scissors with acetone prior to use and between samples. 2. Cut sealed loops and PSD into sections to facilitate dialysis C. Cleaned, cut PSDs are stored in amber jars until dialysis or further processing.

V. Quality Control A. A post deployment cleaning blank should be included with each batch.

VI. Documentation Requirements 1. A completed benchsheet is required. Check http://fses.oregonstate.edu/sop-toc for current version of all required documents. 2. SOP 108 Cleaning Field Deployed Polyethylene Passive Sampling Devices (PSDs) Bench Sheet

VII. Safety and Health A. Please consult Material Safety Data Sheet (MSDS) information on reagents. Personnel performing this method will observe all appropriate Oregon State University laboratory safety procedures.

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VIII. References Not applicable

IX. Validation A. Not applicable

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version SOP 108.01 Cleaning Field Deployed Polyethylene Passive Sampling Devices (PSDs) Bench Sheet

Cleaning Date: Deployment Date: Retrieval Date: Project: Chemists:

WATER Deployed PSD Only ALL Field Deployed PSDs

Dispose, rinse, Submerge in Cut PSD into and refill FSES Sample Wash in 18 MΩ Submerge in First Second sections and cut Store in organic‐ isopropanol Number Sample Name Wash in 1N HCL Water Isopropanol Bath Isopropanol Bath loops clean amber jar bathes Date Initial 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Company and Grade Lot Number Notes: HCl Isopropanol

LFT Storage Location Chemist Review Signature Date

FSES Director Review Signature Date

DOCUMENT UNCONTROLLED IF PRINTED - See http://fses.oregonstate.edu/sop-toc for latest version Page 1 of 1 SOP 406.02 Page 1 of 3

Title: Extraction of Organic Compounds from Polyethylene (PE) Passive Sampling Devices (PSD)

Scope This method describes the extraction of organic compounds by hexanes from polyethylene passive sampling devices. Extracts are concentrated in an appropriate solvent to a final volume for instrumental analysis.

Contributors: S.E. Allan, G.J. Sower, R.P. Scott

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Equipment and Apparatus Note: Clean all glassware and containers for use in organic chemistries (see SOP 2110- Laboratory Container Cleaning procedure). A. Amber glass jars; wide-mouth, screw-cap (50 mL and 500 mL) B. Adjustable pipette C. TurboVapTM 500 Closed Cell evaporator (or equivalent) D. TurboVap™, Zymark LV evaporator (or equivalent) E. TurboVap 500 mL Tubes with 1 mL sensor mark F. Borosilicate centrifuge tubes (sized for TurboVap™) G. Glass pipettes with 2 mL rubber bulbs H. Large glass funnel I. Glass stir rod J. Chromatography vials, 2 mL, amber, Agilent (no substitutes) K. Chromatography vial caps, Agilent (no substitutes) L. Aluminum foil

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II. Reagents A. Hexanes, Fisher, GC-Resolve Grade, for dialysis (no substitutes) B. Hexanes, Fisher, Optima Grade, for glassware rinses C. Acetone, Fisher, Optima, HPLC or Pesticide Grade

III. Standards A. Primary Standards – See SOP 2240 Analytical Standard Receipt, Storage and Documentation. B. Standard Solutions – See the compound specific analysis SOP for the analyte composite and SOP 2250 for standard preparation, storage and expiration.

IV. Sample Preparation Prior to dialysis PSDs should be cleaned (if necessary), cut into pieces and stored in the wide mouth amber jars used for dialysis (see SOP 108). Note: Wear clean nitrile gloves at all times when handling tubing and minimize environmental exposure. Note: If photosensitive compounds are to be determined minimize exposure to light during dialysis and volume reduction steps. Note: If required, surrogate standards can be added immediately prior to dialysis to account for losses during the process.

A. PE PSD Dialysis 1. 1st Dialysis a) Add ~40 mL of hexanes (GC-resolve) for each PSD or enough to completely cover the PSDs. b) Let stand for at least 4 hours or overnight at room temperature. c) Transfer first dialysate to TurboVap tube. (1) Place the funnel on top of the tube and decant hexane into tube. A stir rod or other tool can be used to maintain PSD in the jar. (2) Rinse the following items with n-hexane and capture all rinsate in the tube: (a) PSD and inside of jar (3 times on 2nd dialysis) (b) Inside of the funnel and exterior bottom quarter of the funnel. (c) Glass rod or other tool that was in contact with dialysate. (3) Rinse the funnel and other glassware with acetone and hexanes between samples 2. 2nd Dialysis a) Add the same amount of hexanes as used in section IV.A.1.a to the original amber jar that still contains the PSD. b) Let stand for 2 hours. c) Transfer to TurboVap tube using the same procedure described in IV.A.1.c. (1) Both dialysates are combined into one tube.

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B. Extract Concentration 1. Reduce solvent to approximately 1 mL using the TurboVap closed cell evaporator. 2. Quantitatively transfer extracts to centrifuge tubes using glass pipettes. a) Prior to transfer mark 1 mL volume, or other desired final volume, on the centrifuge tubes 3. Concentrate extract to final volume in appropriate solvent. a) Vortex in centrifuge tube then transfer extract to labeled chromatography vial.

V. Quality Control A. Each batch of extracts should consist of field samples and appropriate field and/or laboratory QC samples to ensure batch extraction quality.

VI. Documentation Requirements A. A completed bench/QC summary sheet is required for all analyses. Check http://fses.oregonstate.edu/sop-toc for current version of all required documents. 1. SOP 406 Extraction of Organic Compounds from PE PSD Benchsheet

VII. Safety and Health A. Please consult Material Safety Data Sheet (MSDS) information on reagents. Personnel performing this method will adhere to Oregon State University Chemical Hygiene Plan and applicable FSES safety SOPs. All procedures involving hexanes should be carried out under a chemical hood. Always use personal protective equipment. Dispose of solvents into solvent waste containers for disposal by Environmental Health and Safety Department, OSU campus.

VIII. References A. Huckins, J. N., Petty, J.D., et al. (2006). Monitors of Organic Chemicals in the Environment; Semipermeable Membrane Devices. New York, Springer.

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Dialysis Start Date: PSD Deployment Date: PSD Retrieval Date: PSD Cleaning Date: Chemists:

First Dialysis - 4 h or Second Dialysis 2 h Reduce sample to ~1 Quantitative Reduce to 1 mL or Transfer samples to overnight (40 mL n- Transfer dialysate to (40 mL n- Combine dialysates - mL using TurboVap transfer of sample less in TurboVap marked amber FSES Sample Hexane/1m PSD) TurboVap tube - Hexane/1m PSD) Rinse PSD, Jar and Closed Cell to marked (1 mL) Evaporator- adjust chrom vials for Completed Number Sample Name Start Time Rinse Funnel 3 times Start Time Funnel 3 times Concentrator centrifuge tube volume to 1 mL storage Completed Date Initial 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Dialysis Quality Control Equipment Location Reagent Blank TurboVap® 500 Closed Cell Concentrator

Reagent Company and Grade Lot Number TurboVap® LV Evaporator Hexanes Fisher, GC Resolve Samples Pipette SN Volume Verification Date Storage Location 1 mL

Surrogate FSES Number Concentration Amount Spiked

Notes: Chemist Review Signature Date

FSES Director Review Signature Date

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Determination of Parent and Methyl Substituted PAHs using GC-MS/MS

Food Safety and Environmental Stewardship Program Oregon State University Standard Operating Procedure

Scope This procedure applies to the analysis of parent and alkyl substituted PAH compounds by GC- MS/MS. Instrument detection limits are approximately 0.33 to 6.44 pg/uL. Sample and standard solutions should be stored with limited exposure to UV light.

Contributors: G. R. Wilson

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Equipment and Apparatus A. Agilent 7890/7000C GC/MS/MS B. Splitless single taper line, Agilent, 4 mm ID, Part# 5190-2292(or equivalent) C. Deactivated glass wool D. Septa, Restek, Thermolite 11mm Part# 27142 (or equivalent) E. Column, J&W Scientific, Select PAH, Part# CP7462, 30m, ID 0.25mm, Film 0.15 um F. Chromatography vials, 2 mL, amber, screw cap, Agilent (or equivalent) G. Chromatography vial inserts, Agilent (or equivalent)

II. Reagents A. Hexanes, Fisher GC Resolv™ (or equivalent) B. Ethyl Acetate, EMD Omnisolve (or equivalent) C. Acetone, EMD Omnisolve (or equivalent)

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D. Isooctane, Fisher, Optima (or equivalent)

III. Standards A. See Table 1 for a list of analytes, surrogates and internal standards. B. Primary Standards are neat standards or solutions ordered from several sources C. Standard Solutions 1. Analytical standards shall be prepared in isooctane or hexane at levels that are comparable to estimated sample levels. The suggested range is 10 to 1000 ng/mL. 2. Expiration of solutions occurs five years after preparation of that solution. Shorter expiration periods may be used and should be used as appropriate, consult with the senior chemist or director if you have any questions. Expired standards must be recertified and documented before use. 3. Fortification solutions are prepared such that the concentration of spiked compounds in the final extract will be 500 pg/uL. This concentration will be verified prior to use in extractions. Expiration of spike solutions (and subsequent re-verification) occurs one (5years from the date of preparation, or as noted per chemist discretion. 4. All stock, standard, and spike solutions are stored at ≤4 oC and allowed to warm to room temperature prior to use. Storage of neat standards and solutions will be based on the suppliers’ recommendations.

IV. Instrument Operating Parameters A. Refer to Table 2 for operating conditions 1. Carrier Gas: Helium (99.99% purity) 2. Pack a small amount of deactivated glass wool into injection port liner 3. Use acetone and hexane wash vials for syringe cleaning between injections

V. Sample Preparation A. See appropriate SOP for sample preparation procedures.

VI. Sample Analysis A. Sample extracts are analyzed on the GC/MS/MS by method I-PAH-XXX- ###_MRM.m (“I” = instrument, “X” = matrix type, “#” = current method version increasing with each calibration or tune) using the appropriate standards and quality control samples. Qualitative identification of analytes in the extract is performed using retention time and mass spectral information. Quantitative analysis is performed by quantifying the relative abundance of characteristic masses (MRM) see Table 1. B. Calibration 1. Standard calibration mixes, containing all target analytes in the method, or target analytes of specific interest, will be run at the beginning of a method or when the verification standard fails DQOs. The calibration standard series will be run, the data edited, and the calibration curve updated prior to running samples. 2. The calibration standard samples should be calibrated according to the procedures outlined in the MS MassHunter User’s Guide. Analytical standards are used to quantify concentrations using a calibration curve specific to each analyte. Curves can be constructed using an average

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response factor (ARF), linear or quadratic curves with or without weighing depending on their individual instrumental response. 3. Before running a batch of samples a continuing calibration verification (CCV) sample will be analyzed. See Table 3 for DQOs and corrective actions.

C. Analysis 1. Use GC/MS/MS method name: I-PAH-XXX-###_MRM. Analytes, surrogate compounds and the internal standard are identified and quantified as pg/µL by the MassHunter software. At least one other MRM is used as a qualifier in the mass spectral display for identification (see Table 1). Analytes are corrected for surrogate compound recovery by the MassHunter software. Surrogate compound responses are a ratio of relative response factors to the internal standard. Surrogate compounds and internal standards can change with different matrices and extraction methods. Please refer to the matrix specific SOP to determine applicable surrogate compounds and internal standards. Analyte instrumental responses are expressed as a ratio of relative response factors to their specified surrogate compound. If the response for a peak exceeds the calibration range by more than nominally 20%, dilute the extract, and adjust the internal standard concentration to 500 pg/ µL and reanalyze.

VII. Calculations A. Fortification levels: 1. [std vol (µL) X std conc (pg/µL)] / final volume of sample (µL) = fortification level (pg/µL)

VIII. Quality Control A. The calibration curve should have an r2 ≥ 0.99 and consist of no fewer than five (5) standards. A continuing calibration verification should be run at the beginning of each day. If the percentage recovery is +/- 30% of the true values sample analysis may begin. If the recoveries are outside the DQOs then the instrument should be re-calibrated and/or troubleshoot as applicable. At least one calibration check should be run each day, for large batches, a calibration check should be run every 10-15 samples. Specific projects may have unique data quality objectives and that criteria may be used, and will take precedent to assess method performance as applicable. Ongoing data quality checks are compared with established performance criteria to determine if the results of analyses meet the performance characteristics of the specific extraction method used. B. In recognition of advances that are occurring in chromatography, the analyst is permitted certain options to improve the separations or lower the cost of measurements. Each time such a modification is made to the method, the analyst is required to document any alterations to the procedure on bench sheets during the analysis. For permanent changes, the standard operating procedures should be formally updated with new validations. C. A solvent blank should be run with each sequence, the concentration of analytes detected in the laboratory reagent blank should be zero. D. The recovery of analytes in laboratory spikes should be between 70% and 130% of the true value.

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IX. Documentation Requirements A. Check http://fses.oregonstate.edu/sop-toc for current version of all required documents. B. A completed bench sheet, QC summary and a copy of the calibration verification results are required for all analyses.

X. Safety and Health A. Please consult Material Safety Data Sheet (MSDS) for information on PAHs and reagents. The toxicity and carcinogenicity of some chemicals used in this method have not been precisely defined; each chemical should be treated as a potential health hazard, and exposure to these chemicals should be minimized. Consult instrument manual for information on safe operation of the GC/MS/MS. Personnel performing this method will observe all appropriate state, federal, and Oregon State University laboratory safety procedures. Further consult SOP4110 for instrumental operation. Precautions should be taken when handling solid chemicals per Oregon State Environmental Health and Safety office for handling carcinogens. Note: handling solids may require specialized trained personnel. More information can be found at http://oregonstate.edu/ehs/carcingn/carcingn.html

XI. References A. Application 5989-4184EN: Synchronous SIM/Scan Low-Level PAH Analysis Using the Agilent Technologies 6890/5975 inert GC/MSD, Agilent Technologies, 2005.

XII. Validation A. This method has been reviewed and validated, the validation packet is located in the fire proof cabinet or the document vault in Weniger.

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Table 1: Polycyclic aromatic hydrocarbon compounds, surrogates and internal standards detected by GC/MS *Surrogate compounds and internal standards can change with different matrices and extraction methods. Please refer to the matrix specific extraction SOP to determine applicable surrogate compounds and internal standards. Listed in Order of Retention on a 30m Select PAH Column: LOD LOQ Compound Name CAS # Type Exp_RT (pg/uL) (pg/uL) Naphthalene-D8 SS 1146-65-2 Surrogate 4.11 0.33 1.00 Naphthalene 91-20-3 Target 4.12 1.04 5.20 2-Methylnaphthalene 91-57-6 Target 4.57 0.70 3.50 1-Methylnaphthalene 90-12-0 Target 4.69 0.28 1.39 2-Ethylnaphthalene 939-27-5 Target 5.00 0.97 4.84 28804-88- 2,6-Dimethylnaphthalene 8 Target 5.07 0.89 4.43 1,6-Dimethylnaphthalene 575-43-9 Target 5.22 0.81 4.05 1,4-dimethylnaphthalene 571-58-4 Target 5.37 1.24 6.22 1,5 dimethylnaphthalene 571-61-9 Target 5.40 1.19 5.93 1,2-Dimethylnaphthalene 573-98-8 Target 5.49 0.94 4.70 93951-97- Acenaphthylene-D8 SS 4 Surrogate 5.66 0.33 1.00 Acenaphthylene 208-96-8 Target 5.69 2.33 11.65 1,8-Dimethylnaphthalene 569-41-5 Target 5.72 0.83 4.15 Acenaphthene 83-32-9 Target 5.86 1.07 5.35 59919-41- 2,6-Diethylnaphthalene 4 Target 6.22 0.81 4.06 81103-79- Fluorene D10-PRC 9 Target 6.67 0.33 1.00 Fluorene 86-73-7 Target 6.73 0.79 3.97 Dibenzothiophene 132-65-0 Target 9.24 0.24 1.20 Phenanthrene-D10 SS 1517-22-2 Surrogate 9.60 1.67 5.00 Phenanthrene 85-01-8 Target 9.71 0.46 2.31 Anthracene 120-12-7 Target 9.86 1.05 5.23 2-Methylphenanthrene 2531-84-2 Target 11.61 0.39 1.93 2-Methylanthracene 613-12-7 Target 11.75 0.47 2.36 1-Methylphenanthrene 832-69-9 Target 12.23 1.06 5.32 9-Methylanthracene 779-02-2 Target 13.24 0.87 4.37 3,6-Dimethylphenanthrene 1576-67-6 Target 13.24 0.42 2.08 2,3-Dimethylanthracene 613-06-9 Target 15.14 0.34 1.71 93951-69- Fluoranthene-D10 SS 0 Surrogate 15.53 1.67 5.00 Fluoranthene 206-44-0 Target 15.66 0.54 2.72 93952-19- p,p' DDE D8-PRC 3 Target 16.26 1.67 5.00 9,10-Dimethylanthracene 781-43-1 Target 17.20 0.85 4.23 Pyrene D10-PRC 1718-52-1 Target 17.20 Pyrene 129-00-0 Target 17.20 0.42 2.09

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Retene 483-65-8 Target 17.38 0.84 4.19 Benzo(a)fluorene 238-84-6 Target 19.35 1.67 5.00 Benzo(b)flourene 243-17-4 Target 19.73 1.67 5.00 Benzo(c)fluorene 205-12-9 Target 19.83 0.30 1.50 1-Methylpyrene 2381-21-7 Target 20.89 0.38 1.90 Benz(a)anthracene 56-55-3 Target 25.75 0.75 3.77 27208-37- Cyclopenta(c,d)pyrene 3 Target 25.95 0.53 2.67 Chrysene-D12 SS 1719-03-5 Surrogate 25.95 1.67 5.00 Triphenylene 217-59-4 Target 26.04 0.41 2.04 Chrysene 218-01-9 Target 26.10 0.50 2.49 6-Methylchrysene 1705-85-7 Target 27.67 0.89 4.44 5-Methylchrysene 3697-24-3 Target 27.74 1.67 5.00 Benzo(b)fluoranthene D12- PRC 205-99-2 Target 30.25 1.67 5.00 Benzo(b)fluoranthene 205-99-2 Target 30.35 0.37 1.85 7,12- Dimethylbenz(a)anthracene 57-97-6 Target 30.43 0.94 4.71 Benzo(k)fluoranthene 207-08-9 Target 30.48 0.53 2.63 Benzo(j)fluoranthene 205-82-3 Target 30.56 0.56 2.79 202-33-5 & 199-54- Benz[j]+[e]aceanthrylene 2 Target 31.25 1.67 5.00 Benzo(e)pyrene 192-97-2 Target 32.25 0.71 3.53 63466-71- Benzo(a pyrene-D12 SS 7 Surrogate 32.41 1.67 5.00 Benzo(a)pyrene 50-32-8 Target 32.58 1.18 5.90 Perylene-D12 1520-96-3 ISTD 33.14 Indeno(1,2,3-c,d) pyrene 193-39-5 Target 40.34 0.26 1.32 Dibenz(a,h)anthracene 53-70-3 Target 40.41 1.02 5.11 Picene 213-46-7 Target 41.29 0.74 3.72 93951-66- Benzo(ghi)perylene-D12 SS 7 Surrogate 41.60 1.67 5.00 Benzo(ghi)perylene 191-24-2 Target 41.71 0.34 1.71 Anthanthrene 191-26-4 Target 42.20 0.33 1.65 Naptho[1,2-b]fluoranthene 5385-22-8 Target 44.20 1.67 5.00 Naptho[2,3-j]fluoranthene 205-83-4 Target 44.28 1.67 5.00 Dibenzo(a,e)fluoroanthene 5385-75-1 Target 44.43 0.47 2.36 Dibenzo(a,l)pyrene 191-30-0 Target 44.59 0.48 2.41 Naptho[2,3-k]fluoranthene 207-18-1 Target 44.84 1.67 5.00 Naptho[2,3-e]pyrene 193-09-9 Target 45.18 1.67 5.00 Dibenzo(a,e)pyrene 192-65-4 Target 45.50 6.44 32.22 Coronene 191-07-1 Target 45.69 0.70 3.49 Dibenzo(e,l)pyrene 192-51-8 Target 45.72 1.67 5.00 Naptho[2,3-a]pyrene 196-42-9 Target 45.86 1.67 5.00 Benzo(b)perylene 197-70-6 Target 45.93 1.67 5.00

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Dibenzo(a,i)pyrene 189-55-9 Target 46.03 1.42 7.10 Dibenzo(a,h)pyrene 189-64-0 Target 46.83 0.52 2.60

Table 2 : Instrument Control Parameters (Copied from MassHunter acqmeth.txt)

INSTRUMENT CONTROL PARAMETERS: 7000 QQQ ------

D:\MassHunter\GCMS\1\methods\PAH-PSD-014_MRM.M Thu Apr 03 12:54:04 2014

Control Information ------

Sample Inlet : GC Injection Source : GC ALS Injection Location: Rear Mass Spectrometer : Enabled

No Sample Prep method has been assigned to this method.

GC Oven Equilibration Time 0.5 min Max Temperature 350 °C Slow Fan Disabled Oven Program On Oven Program 60 °C for 1 min Oven#1 then 40 °C/min to 180 °C for 0 min Oven#2 then 3 °C/min to 230 °C for 0 min Oven#3 then 1.5 °C/min to 235 °C for 0 min Oven#4 then 15 °C/min to 280 °C for 10 min Oven#5 then 6 °C/min to 298 °C for 0 min Oven#6 then 16 °C/min to 350 °C for 4 min Run Time 47.25 min Cryo Off

QQQ Collision Cell EPC He Quench Gas On 2.25 mL/min N2 Collision Gas On 1.5 mL/min

ALS Back Injector Syringe Size 10 μL Injection Volume 1 μL Solvent A Washes (PreInj) 2 Solvent A Washes (PostInj) 3 Solvent A Volume 8 μL Solvent B Washes (PreInj) 2 Solvent B Washes (PostInj) 3 Solvent B Volume 8 μL Sample Washes 0 Sample Wash Volume 8 μL Sample Pumps 4 Dwell Time (PreInj) 0 min

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Dwell Time (PostInj) 0 min Solvent Wash Draw Speed 300 μL/min Solvent Wash Dispense Speed 6000 μL/min Sample Wash Draw Speed 300 μL/min Sample Wash Dispense Speed 6000 μL/min Injection Dispense Speed 6000 μL/min Viscosity Delay 0 sec Sample Depth Disabled Injection Type Standard L1 Airgap 0.2 μL

Tray Barcode heater Disabled Barcode mixer Disabled

Sample Overlap Mode Sample overlap is not enabled

ALS Errors Pause for user interaction

Front MM Inlet He ***Excluded from Affecting GC's Readiness State*** Mode Pulsed Splitless Heater Off Pressure Off Total Flow Off Septum Purge Flow Off Septum Purge Flow Mode Switched Temperature Program Off Temperature Program 320 °C for 0 min Run Time 47.25 min Injection Pulse Pressure 35 psi Until 0.3 min Purge Flow to Split Vent 50 mL/min at 0.7 min Cryo Off

Back SS Inlet He Mode Pulsed Splitless Heater On 320 °C Pressure On 17.677 psi Total Flow On 30 mL/min Septum Purge Flow On 3 mL/min Gas Saver On 15 After 2 min mL/min Injection Pulse Pressure 35 psi Until 0.3 min Purge Flow to Split Vent 25 mL/min at 0.7 min

Thermal Aux 2 (MSD Transfer Line) Heater On 320 °C

Column Column #1 J&W CP7462 Select PAH -60 °C—350 °C (350 °C): 30 m x 250 μm x 0.15 μm In Back SS Inlet He Out MSD (Initial) 60 °C Pressure 17.677 psi Flow 2 mL/min Average Velocity 51.792 cm/sec

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Holdup Time 0.96539 min Flow Program On Flow Program 2 mL/min for 0 min Run Time 47.25 min

APC Aux EPC 4 H2 Pressure Program On Pressure Program 50 psi for 0 min Run Time 47.25 min Aux EPC 5 He Pressure Program Off Pressure Program 5 psi for 0 min Run Time 47.25 min Aux EPC 6 H2 Pressure Program On Pressure Program 2 psi for 0 min Run Time 47.25 min

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Table 3 : Data Quality Objectives, Acceptance Criteria and Corrective Actions Acceptance Corrective QC Sample Purpose Frequency Criteria Action Prior to project Perform analyses R2 of ≥0.99 if instrument Initial Calibration Accuracy and if post- linear, ≥0.995 maintenance, maintenance if quadratic and reanalyze calibration check fails Signal to Perform Prior to noise (peak instrument Instrument Detection Detection Limit project Limits to peak) ratio maintenance, analyses is above 3 Reanalyze ±30% of true Perform Accuracy One per 10- value for at instrument despite matrix or 15 samples, Continuing Calibration least 80% of maintenance Verification instrument or as target and re-analyze variability necessary analytes samples Below Re-analyze, analyte perform Detection Limit, Beginning of Instrument Blank Instrument instrument contamination each batch Detection maintenance, Limit and/or flag data Analyte One per 25 Preparation and percent Flag Data as Sample Spike Field handling bias recovery appropriate Samples 50% to 150% Re-analyze if a standard, Each Percent perform Internal Standard Peak Analytical Bias sample and detected instrument Area standard 50% to 100% maintenance, and/or flag sample data Re-analyze if it Percent Each is a blank or Surrogate Recovery Analytical Bias Recovery sample standard, flag 50% to 150% sample data

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Table 4 : Quantifier and Qualifier Ions and Collision Cell Voltages for each compound Quantifier Quantifier Collision Qualifier Qualifier Collision Precursor Product Energy Precursor Product Energy Name CAS # RT Ion Ion (V) Ion Ion (V) Naphthalene-D8 SS 1146-65-2 4.11 136 108 20 136 84 25 Naphthalene 91-20-3 4.12 128 102 20 128 78 20 2-Methylnaphthalene 91-57-6 4.57 142 141 15 142 115.1 20 1-Methylnaphthalene 90-12-0 4.69 142 141 15 142 115.1 20 2-Ethylnaphthalene 939-27-5 5.00 141 115 15 156 141 15 2,6-Dimethylnaphthalene 28804-88-8 5.07 156 141 15 141 115 15 1,6-Dimethylnaphthalene 575-43-9 5.22 156 141 15 141 115 15 1,4-dimethylnaphthalene 571-58-4 5.37 156 141 15 141 115 15 1,5 dimethylnaphthalene 571-61-9 5.40 156 141 15 141 115 15 1,2-Dimethylnaphthalene 573-98-8 5.49 156 141 15 141 115 15 Acenaphthylene-D8 SS 93951-97-4 5.66 160 158 30 158 156 30 Acenaphthylene 208-96-8 5.69 152 126 30 152 102 30 1,8-Dimethylnaphthalene 569-41-5 5.72 156 141 15 141 115 15 Acenaphthene 83-32-9 5.86 153 127 30 153 77 45 2,6-Diethylnaphthalene 59919-41-4 6.22 169 154 20 169 153 30 Fluorene D10-PRC 81103-79-9 6.67 176 174 15 174 172 20 Fluorene 86-73-7 6.73 166 165 15 165 164 20 Dibenzothiophene 132-65-0 9.24 184 152 25 184 139 30 Phenanthrene-D10 SS 1517-22-2 9.60 188 160 20 188 186 15 Phenanthrene 85-01-8 9.71 178 152 25 176 150 25 Anthracene 120-12-7 9.86 178 152 25 176 150 25 2-Methylphenanthrene 2531-84-2 11.61 192 191 20 192 189 40 2-Methylanthracene 613-12-7 11.75 192 191 20 192 189 40 1-Methylphenanthrene 832-69-9 12.23 192 191 20 192 189 40 9-Methylanthracene 779-02-2 13.24 192 191 20 192 189 40 3,6-Dimethylphenanthrene 1576-67-6 13.24 206 191 16 206 205 16 2,3-Dimethylanthracene 613-06-9 15.14 206 191 16 206 205 16 Fluoranthene-D10 SS 93951-69-0 15.53 212 208 35 210 208 15

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Fluoranthene 206-44-0 15.66 202 200 35 201 200 15 p,p' DDE D8-PRC 93952-19-3 16.26 254 184 30 326 254 15 9,10-Dimethylanthracene 781-43-1 17.20 206 191 16 206 205 16 Pyrene D10-PRC 1718-52-1 17.20 212 208 35 210 208 15 Pyrene 129-00-0 17.20 202 200 35 201 200 15 Retene 483-65-8 17.38 219 204 20 219 203 20 Benzo(a)fluorene 238-84-6 19.35 216 215 25 215 189 25 Benzo(b)flourene 243-17-4 19.73 216 215 25 215 189 25 Benzo(c)fluorene 205-12-9 19.83 216 215 25 215 189 25 1-Methylpyrene 2381-21-7 20.89 216 215 25 215 189 25 Benz(a)anthracene 56-55-3 25.75 228 226 30 113 112 10 Cyclopenta(c,d)pyrene 27208-37-3 25.95 226 225 30 226 224 40 Chrysene-D12 SS 1719-03-5 25.95 240 236 35 240 212 30 Triphenylene 217-59-4 26.04 228 226 30 113 112 10 Chrysene 218-01-9 26.10 228 226 30 113 112 10 6-Methylchrysene 1705-85-7 27.67 242 241 20 241 239 30 5-Methylchrysene 3697-24-3 27.74 242 241 20 241 239 30 Benzo(b)fluoranthene D12-PRC 205-99-2 30.25 264 260 35 264 236 30 Benzo(b)fluoranthene 205-99-2 30.35 252 250 30 126 113 10 7,12-Dimethylbenz(a)anthracene 57-97-6 30.43 256 241 15 241 239 25 Benzo(k)fluoranthene 207-08-9 30.48 252 250 30 126 113 10 Benzo(j)fluoranthene 205-82-3 30.56 252 250 30 126 113 10 202-33-5 & Benz[j]+[e]aceanthrylene 199-54-2 31.25 252 250 30 250 248 30 Benzo(e)pyrene 192-97-2 32.25 252 250 30 126 113 10 Benzo(a pyrene-D12 SS 63466-71-7 32.41 264 260 35 264 236 30 Benzo(a)pyrene 50-32-8 32.58 252 250 30 126 113 10 Perylene-D12 1520-96-3 33.14 264 260 35 264 236 30 Indeno(1,2,3-c,d) pyrene 193-39-5 40.34 276 274 45 138 137 15 Dibenz(a,h)anthracene 53-70-3 40.41 278 276 35 125 124 10 Picene 213-46-7 41.29 278 276 35 125 124 10 Benzo(ghi)perylene-D12 SS 93951-66-7 41.60 288 284 40 144 142 20

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Benzo(ghi)perylene 191-24-2 41.71 276 274 45 138 137 15 Anthanthrene 191-26-4 42.20 276 274 45 138 137 15 Naptho[1,2-b]fluoranthene 5385-22-8 44.20 302 300 40 302 301 20 Naptho[2,3-j]fluoranthene 205-83-4 44.28 302 300 40 302 301 20 Dibenzo(a,e)fluoroanthene 5385-75-1 44.43 302 300 40 302 301 20 Dibenzo(a,l)pyrene 191-30-0 44.59 302 300 40 302 301 20 Naptho[2,3-k]fluoranthene 207-18-1 44.84 302 300 40 302 301 20 Naptho[2,3-e]pyrene 193-09-9 45.18 302 300 40 302 301 20 Dibenzo(a,e)pyrene 192-65-4 45.50 302 300 40 302 301 20 Coronene 191-07-1 45.69 300 298 50 300 299 35 Dibenzo(e,l)pyrene 192-51-8 45.72 302 300 40 302 301 20 Naptho[2,3-a]pyrene 196-42-9 45.86 302 300 40 302 301 20 Benzo(b)perylene 197-70-6 45.93 302 300 40 302 301 20 Dibenzo(a,i)pyrene 189-55-9 46.03 302 300 40 302 301 20 Dibenzo(a,h)pyrene 189-64-0 46.83 302 300 40 302 301 20

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Title: Calculation of Freely Dissolved Water Concentrations of Organic Compounds Derived from Polyethylene Passive Sampling Devices (PSD)

Scope This method describes the calculations required for determining surface water and sediment porewater concentrations of polycyclic aromatic hydrocarbons (PAH), oxygenated polycyclic aromatic hydrocarbons (OPAHs), and pesticides that have been collected using polyethylene (PE) passive sampling devices (PSD). Prior analysis by applicable standard analytical method is required to determine analyte concentrations in the sampler.

Contributors: G. Sower, L. Quarles, K.A. Anderson

Responsibilities Staff members involved in performing this work are responsible for reading, understanding and complying with the requirements for this SOP. The Director is responsible for ensuring that the content of this SOP is complied with and that qualified staff performs these analyses. The senior chemists are responsible for informing staff members of the requirements and interpretation of this SOP and are responsible for enforcing this SOP.

Status This document is considered current standard operating procedure of the Food Safety and Environmental Stewardship Laboratory when management approval is documented by signature below. This Standard Operating Procedure is effective on the date of approval signature and supersedes all previous versions.

Approved Director Kim A. Anderson, Ph.D. Title Date

Historical File Signature/Initials Date

I. Laboratory quantitation of analytes in PSDs A. Fortification levels for one PSD: 1. PRC fortification solution must be prepared by a chemist in accordance with the needs of the project. 2. [std. vol. (µL) X std. conc. (µg/µL)] / wt. of sample (g*) = fortification level (µg/g).

B. Quantitative analysis to determine unknown sample levels: 1. See the specific analyte SOP analytical procedure for quantitative measurement.

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II. Calculations using performance reference compounds (PRCs) [4]. A. The following calculations are performed using XLIMS data to excel feature. This process will place detection/reporting limit flagged concentrations from the instrument into the attached excel spreadsheet and produce one file per sample. B. The chemist should verify: 1. Quantity of PE PSDs 2. PRC fortification levels 3. Duration of deployment in days C. Final values are stored in XLIMS using the resulting excel file.

*Note the calculation described does not account for temperature differences and assumes that your sampling system temperature range is between 2 and 30 C. “The experimental evidence suggests that Ksw values are not temperature dependent in the 2 to 30 C temperature range” Huckins et al 2006 page 53. See Huckins et al 2006 (and references therein), page 53- 56 for explaination and how to account for temperature if required.

Calculation of Sampling Rate (Rs) of PRC’s: , , = ( × 10 × )/1000 𝑙𝑙𝑙𝑙𝑙𝑙𝐾𝐾 𝑠𝑠𝑠𝑠 𝑃𝑃𝑃𝑃𝑃𝑃 𝑠𝑠 𝑃𝑃𝑃𝑃𝑃𝑃 𝑠𝑠 𝑒𝑒 where the𝑅𝑅 sampler water𝑉𝑉 partition coefficient𝑘𝑘 (Ksw) is given by: = + 2.321( ) 0.1618( ) 2 𝑠𝑠𝑠𝑠 0 𝑜𝑜𝑜𝑜 𝑜𝑜𝑜𝑜 𝐿𝐿𝐿𝐿𝐿𝐿 𝐾𝐾 = 𝑎𝑎2.61 𝑙𝑙𝑙𝑙𝑙𝑙𝐾𝐾, −, 4,4 𝑙𝑙𝑙𝑙𝑙𝑙𝐾𝐾 = 3.2 ′ 0 𝑎𝑎( − 𝑓𝑓𝑓𝑓𝑓𝑓 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 54𝑃𝑃𝑃𝑃 𝑃𝑃𝑃𝑃 − 3.𝐷𝐷𝐷𝐷𝐷𝐷28) 0 𝑎𝑎 − 𝑓𝑓𝑓𝑓𝑓𝑓 𝑝𝑝 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝐹𝐹𝐹𝐹𝐹𝐹𝐹𝐹the𝐻𝐻𝐻𝐻 volume𝐻𝐻𝐻𝐻𝐻𝐻𝐻𝐻𝐻𝐻 𝑝𝑝 (𝑝𝑝𝑝𝑝Vs)𝑝𝑝 of sampler𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒 is: = (# ) × (5.0 ) 3 𝑠𝑠 the PRC release𝑉𝑉 rate𝑜𝑜𝑜𝑜 𝑃𝑃 constant𝑃𝑃 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 (ke) is estimated𝑐𝑐𝑐𝑐 using: = ln ( )/ 𝑡𝑡𝐸𝐸 𝑒𝑒 𝑘𝑘 − 0 𝐸𝐸 where:𝑡𝑡 = = 0 = = 0 𝑡𝑡 =𝑃𝑃𝑃𝑃 𝑃𝑃 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑖𝑖𝑖𝑖 𝑃𝑃𝑃𝑃 𝑎𝑎𝑎𝑎 𝑡𝑡𝑡𝑡𝑡𝑡𝑡𝑡 𝐸𝐸 𝑡𝑡 𝑃𝑃𝑃𝑃𝑃𝑃 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑖𝑖𝑖𝑖 𝑃𝑃𝑃𝑃 𝑎𝑎𝑎𝑎 𝑡𝑡𝑡𝑡𝑡𝑡𝑡𝑡 𝐸𝐸 Calculation of Water𝐸𝐸 Concentration𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑 (Cw,𝑑𝑑𝑑𝑑𝑑𝑑analyte𝑖𝑖𝑖𝑖)𝑑𝑑𝑑𝑑 for𝑑𝑑𝑑𝑑 Target Compounds:

, = × 1000 , × × 𝑎𝑎𝑎𝑎(1𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎exp𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 ) 𝑤𝑤 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 × , 𝐶𝐶 𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑠𝑠 𝑠𝑠𝑠𝑠 𝑅𝑅 𝐸𝐸 𝑉𝑉 𝐾𝐾 − �− 𝑉𝑉𝑠𝑠 𝐾𝐾𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎�

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, = × 1000 , × × , 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎(1 𝑎𝑎exp𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 ) 𝑤𝑤 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 × , 𝐶𝐶 𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑠𝑠 𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑅𝑅 𝐸𝐸 𝑉𝑉 𝐾𝐾 − �− 𝑠𝑠 𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎� where the sampling rate of the target compound𝑉𝑉 𝐾𝐾 (Rs,analyte) is:

, = , × 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑅𝑅𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑅𝑅and:𝑠𝑠 𝑃𝑃𝑃𝑃𝑃𝑃 � � = 0.0130 0.3173 𝑎𝑎𝑃𝑃𝑃𝑃𝑃𝑃+ 2.244 ( 3 2 60 3.35) 𝑜𝑜𝑜𝑜 𝑜𝑜𝑜𝑜 𝑜𝑜𝑜𝑜 *Remember to use appropriate𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 Kow for𝑙𝑙 K𝑙𝑙𝑙𝑙sw,PRC𝐾𝐾 and− Ksw,analayte𝑙𝑙𝑙𝑙𝑙𝑙 calculations𝐾𝐾 𝑙𝑙𝑙𝑙𝑙𝑙𝐾𝐾 𝐹𝐹𝐹𝐹𝐹𝐹𝐹𝐹 𝐻𝐻𝐻𝐻 𝐻𝐻𝐻𝐻𝐻𝐻𝐻𝐻𝐻𝐻 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒

III. References 1. Petty, J. D.; Huckins, J. N.; Martin, D. B.; Adornato, T. G., Use of semipermeable membrane devices (SPMDS) to determine bioavailable organochlorine pesticide residues in streams receiving irrigation drainwater. Chemosphere 1995, 30, (10), 1891- 1903. 2. Huckins, J. N.; Petty, J. D.; Orazio, C. E.; Lebo, J. A.; Clark, R. C.; Gibson, V. L.; Gala, W. R.; Echols, K. R., Determination of uptake kinetics (Sampling rates) by lipid- containing semipermeable membrane devices (SPMDs) for polycyclic aromatic hydrocarbons (PAHs) in water. Environmental Science & Technology 1999, 33, (21), 3918-3923. 3. Luellen, D. R.; Shea, D., Calibration and Field Verification of Semipermeable Membrane Devices for Measuring Polycyclic Aromatic Hydrocarbons in Water. Environmental Science & Technology 2002, 36, (8), 1791-1797. 4. Huckins, J. N.; Petty, J. D.; Booij, K., Monitors of organic chemicals in the environment : semipermeable membrane devices. Springer: New York, 2006; p xv, 223. 5. Mackay, D.; Shiu, W. Y.; Ma, K. C., Physical-Chemical Properties and Environmental Fate Handbook. CRC Press: Boca Raton, FL, 1999. 6. Neff, J. M.; Burns, W. A., Estimation of polycyclic aromatic hydrocarbon concentrations in the water column based on tissue residues in mussels and salmon: An equilibrium partitioning approach. Environmental Toxicology and Chemistry 1996, 15, (12), 2240-2253. 7. Food Safety Environmental Stewardship Program SOP 2120: Preparation of Polyethylene Passive Sampling Devices for Environmental Sampling Equipment.

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Table 1. Target PAH compounds with suggested PRC compound and estimated method detection limit (MDL) based on three week deployment with 5 PSDs composited in surface water and 1 PSD in sediment pore water at a Portland Harbor Superfund Site with analysis by SOP 418. Kow values are from: US EPA. [2014]. Estimation Programs Interface Suite™ for Microsoft® Windows, v 4.10. United States Environmental Protection Agency, Washington, DC, USA. MDL(ng/L) Compound CAS # log Kow PRC Surface water Pore water Naphthalene 91-20-3 3.30 Fluorene-d10 0.088 0.44 2-Methylnaphthalene 91-57-6 3.86 Fluorene-d10 0.016 0.081 1-Methylnaphthalene 90-12-2 3.87 Fluorene-d10 0.0063 0.031 2-Ethylnaphthalene 939-27-5 4.38 Fluorene-d10 0.0069 0.034 2,6-Dimethylnaphthalene 581-42-0 4.31 Fluorene-d10 0.0073 0.036 1,6-Dimethylnaphthalene 575-43-9 4.26 Fluorene-d10 0.0074 0.037 1,4-dimethylnaphthalene 571-53-4 4.37 Fluorene-d10 0.0090 0.045 1,5 dimethylnaphthalene 571-61-9 4.38 Fluorene-d10 0.0084 0.042 1,2-Dimethylnaphthalene 573-98-8 4.31 Fluorene-d10 0.0077 0.039 1,8-Dimethylnaphthalene 569-41-5 4.26 Fluorene-d10 0.0076 0.038 2,6-Diethylnaphthalene 59919-41-4 4.30 Fluorene-d10 0.0068 0.034 Acenaphthylene 208-96-8 3.94 Fluorene-d10 0.020 0.10 Acenaphthene 83-32-9 3.92 Fluorene-d10 0.046 0.23 Fluorene 86-73-7 4.18 Fluorene-d10 0.0086 0.043 Dibenzothiophene 132-65-0 4.38 Fluorene-d10 0.0017 0.0085 Phenanthrene 85-01-8 4.46 Fluorene-d10 0.0028 0.014 Anthracene 120-12-7 4.45 Fluorene-d10 0.0065 0.032 2-Methylphenanthrene 2531-84-2 4.86 Pyrene-d10 0.0015 0.0074 2-Methylanthracene 613-12-7 5.00 Pyrene-d10 0.0016 0.0079 1-Methylphenanthrene 832-69-9 5.08 Pyrene-d10 0.0034 0.017 9-Methylanthracene 779-02-2 5.07 Pyrene-d10 0.0028 0.014 3,6-Dimethylphenanthrene 1576-67-6 5.44 Benzo[b]fluoranthene-d12 0.0015 0.0074 Fluoranthene 613-06-9 5.22 Pyrene-d10 0.0016 0.0080 2,3-Dimethylanthracene 206-44-0 5.60 Benzo[b]fluoranthene-d12 0.0012 0.0060 9,10-Dimethylanthracene 781-43-1 5.69 Benzo[b]fluoranthene-d12 0.0030 0.015

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Pyrene 129-00-0 4.88 Pyrene-d10 0.0016 0.0078 Retene 483-65-8 6.35 Benzo[b]fluoranthene-d12 0.0035 0.017 Benzo(a)fluorene 238-84-6 5.40 Benzo[b]fluoranthene-d12 0.0036 0.018 Benzo(b)flourene 243-17-4 5.77 Benzo[b]fluoranthene-d12 0.0035 0.018 Benzo(c)fluorene 205-12-9 5.19 Pyrene-d10 0.00089 0.004 1-Methylpyrene 238-71-7 5.48 Benzo[b]fluoranthene-d12 0.0013 0.007 Benz(a)anthracene 56-55-3 5.76 Benzo[b]fluoranthene-d12 0.0027 0.013 Cyclopenta(c,d)pyrene 27208-37-3 5.50 Benzo[b]fluoranthene-d12 0.0019 0.0094 Triphenylene 217-59-4 5.49 Benzo[b]fluoranthene-d12 0.0014 0.0072 Chrysene 218-01-9 5.81 Benzo[b]fluoranthene-d12 0.0018 0.0088 6-Methylchrysene 1705-85-7 6.07 Benzo[b]fluoranthene-d12 0.0033 0.017 5-Methylchrysene 3697-24-3 6.07 Benzo[b]fluoranthene-d12 0.0038 0.019 Benzo(b)fluoranthene 205-99-2 5.78 Benzo[b]fluoranthene-d12 0.0013 0.0065 7,12-Dimethylbenz(a)anthracene 57-97-6 5.80 Benzo[b]fluoranthene-d12 0.0033 0.017 Benzo(k)fluoranthene 207-08-9 6.11 Benzo[b]fluoranthene-d12 0.0020 0.010 Benzo(j)fluoranthene 205-82-3 6.11 Benzo[b]fluoranthene-d12 0.0021 0.011 Benzo(e)pyrene 192-97-2 6.44 Benzo[b]fluoranthene-d12 0.0030 0.015 Benzo(a)pyrene 50-32-8 6.13 Benzo[b]fluoranthene-d12 0.0045 0.023 Indeno(1,2,3-c,d) pyrene 193-39-5 6.70 Benzo[b]fluoranthene-d12 0.0013 0.0065 Dibenz(a,h)anthracene 53-70-3 6.75 Benzo[b]fluoranthene-d12 0.0052 0.026 Picene 213-46-7 7.11 Benzo[b]fluoranthene-d12 0.0047 0.024 Benzo(ghi)perylene 191-24-2 6.63 Benzo[b]fluoranthene-d12 0.0016 0.0081 Anthanthrene 191-26-4 7.04 Benzo[b]fluoranthene-d12 0.0020 0.010 Naptho[1,2-b]fluoranthene 5385-22-8 7.29 Benzo[b]fluoranthene-d12 0.0071 0.036 Naptho[2,3-j]fluoranthene 205-83-4 7.29 Benzo[b]fluoranthene-d12 0.0071 0.036 Dibenzo(a,e)fluoroanthene 5385-75-1 7.28 Benzo[b]fluoranthene-d12 0.0033 0.017 Dibenzo(a,l)pyrene 191-30-0 7.71 Benzo[b]fluoranthene-d12 0.0047 0.023 Naptho[2,3-k]fluoranthene 207-18-1 7.29 Benzo[b]fluoranthene-d12 0.0071 0.036 Naptho[2,3-e]pyrene 193-09-9 7.29 Benzo[b]fluoranthene-d12 0.0071 0.036

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Dibenzo(a,e)pyrene 192-65-4 7.28 Benzo[b]fluoranthene-d12 0.046 0.23 Coronene 191-07-1 7.64 Benzo[b]fluoranthene-d12 0.0064 0.032 Dibenzo(e,l)pyrene 192-51-8 6.20 Benzo[b]fluoranthene-d12 0.0039 0.020 Naptho[2,3-a]pyrene 196-42-9 7.29 Benzo[b]fluoranthene-d12 0.0071 0.036 Benzo(b)perylene 197-70-6 7.00 Benzo[b]fluoranthene-d12 0.0059 0.029 Dibenzo(a,i)pyrene 189-55-9 7.28 Benzo[b]fluoranthene-d12 0.010 0.050 Dibenzo(a,h)pyrene 189-64-0 7.28 Benzo[b]fluoranthene-d12 0.0037 0.018 Pentachlorophenol 87-86-5 5.12 Fluorene-d10 TBD TBD

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Table 2. Target OPAH compounds from SOP 414 with suggested PRC compounds. Kow values are from: US EPA. [2014]. Estimation Programs Interface Suite™ for Microsoft® Windows, v 4.10. United States Environmental Protection Agency, Washington, DC, USA. Compound Cas # logKow PRC 1,4-Benzoquinone 106-51-4 0.20 9,10-Anthraquinone-d9 Chromone 491-38-3 1.38 9,10-Anthraquinone-d9 1,4-Naphthoquinone 130-15-4 1.71 9,10-Anthraquinone-d9 1,2-Naphthoquinone 524-42-5 2.11 9,10-Anthraquinone-d9 9-Fluorenone 486-25-9 3.58 9,10-Anthraquinone-d9 Xanthone 90-47-1 3.39 9,10-Anthraquinone-d9 Acenaphthenequinone 82-86-0 1.95 9,10-Anthraquinone-d9 Perinapthenone 548-39-0 3.39 9,10-Anthraquinone-d9 Phenanthrene-1,4-dione 569-15-3 2.52 9,10-Anthraquinone-d9 9,10-Anthraquinone 84-65-1 3.39 9,10-Anthraquinone-d9 1,4-Anthraquinone 635-12-1 2.84 9,10-Anthraquinone-d9 4H-Cyclopenta(def)phenanthren-4-one 5737-13-3 4.14 9,10-Anthraquinone-d9 9,10-Phenanthrenequinone 84-11-7 3.56 9,10-Anthraquinone-d9 2-Ethylanthraquinone 84-51-5 4.37 9,10-Anthraquinone-d9 Benzofluorenone 76723-60-9 4.73 9,10-Anthraquinone-d9 Benzanthrone 82-05-3 4.81 9,10-Anthraquinone-d9 Aceanthracenequinone 11/1/6373 4.15 9,10-Anthraquinone-d9 Pyrene-4,5-dione 6217-22-7 4.15 9,10-Anthraquinone-d9 7,12-benz(a)anthracenquinone 2498-66-0 4.40 9,10-Anthraquinone-d9 Benzo(c)phenanthrene(1,4)quinone 109699-80-1 3.59 9,10-Anthraquinone-d9 5,12-Naphthacene-quinone 1090-13-7 4.52 9,10-Anthraquinone-d9 Benzo(cd)pyrenone 80398-28-3 5.31 9,10-Anthraquinone-d9

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Table 3. Target Pesticides compounds from SOP 404 with suggested PRC compound. Kow values are from: US EPA. [2014]. Estimation Programs Interface Suite™ for Microsoft® Windows, v 4.10. United States Environmental Protection Agency, Washington, DC, USA.

Compound Cas # logKow PRC 1,2-Dibromo-3-chloropropane 96-12-8 2.96 PCB 65 (d5) Hexachlorocyclopentadiene 77-47-4 5.04 PCB 65 (d5) Etridiazole 259-15-9 3.37 PCB 65 (d5) Chloroneb 2675-77-6 3.44 PCB 65 (d5) Trifluralin 1582-09-8 5.34 PCB 65 (d5) Propachlor 1918-16-7 2.18 PCB 65 (d5) Prophos 13194-48-4 2.15 PCB 65 (d5) Diallate 2303-16-4 0.73 PCB 65 (d5) Hexachlorobenzene 118-74-1 5.31 PCB 65 (d5) a-BHC 319-84-6 3.80 PCB 65 (d5) Diazinon 333-41-5 3.81 PCB 65 (d5) Pentachloronitrobenzene 82-68-8 4.64 PCB 65 (d5) Lindane (g-BHC) 58-89-9 3.55 PCB 65 (d5) Simazine 122-34-9 2.18 PCB 65 (d5) Dimethoate 60-51-5 0.70 PCB 65 (d5) b-BHC 319-85-7 3.81 PCB 65 (d5) Heptachlor 76-44-8 5.58 PCB 65 (d5) Alachlor 15972-60-8 2.89 PCB 65 (d5) d-BHC 319-86-8 3.78 PCB 65 (d5) Chlorothalonil 1897-45-6 2.92 PCB 65 (d5) Aldrin 309-00-2 6.50 PCB 65 (d5) Propanil 709-98-8 3.07 PCB 65 (d5) Metolachlor 51218-45-2 2.90 PCB 65 (d5) o,p'-Dicofol 10606-46-9 5.81 PCB 65 (d5) Dacthal 1861-32-1 4.30 PCB 65 (d5) Chlorpyrifos 2921-88-2 4.96 PCB 65 (d5) Fipronil sulfide 120067-83-6 4.82 PCB 65 (d5) Fipronil 120068-37-3 4.00 PCB 65 (d5) Isodrin 465-73-6 6.75 PCB 65 (d5) p,p'-Dicofol 115-32-2 5.02 PCB 65 (d5) Heptachlor epoxide 1024-57-3 4.98 PCB 65 (d5) Pendimethalin 40487-42-1 2.62 PCB 65 (d5) g-Chlordane (trans) 5103-74-2 6.27 PCB 65 (d5) Trans-Nonachlor 39765-80-5 6.35 PCB 65 (d5) a-Chlordane (cis) 5103-71-9 5.60 PCB 65 (d5) Endosulfan I 959-98-8 3.62 PCB 65 (d5) Fipronil Sulfone 120068-36-2 4.82 PCB 65 (d5)

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Oxadiazon 19666-30-9 4.80 PCB 65 (d5) p,p'-DDE 72-55-9 6.51 PCB 116 (d5) Dieldrin 60-57-1 5.20 PCB 116 (d5) Captan 133-06-2 2.35 PCB 116 (d5) Chloropropylate 5836-10-2 4.41 PCB 116 (d5) Perthane 72-56-0 6.66 PCB 116 (d5) Chlorobenzilate 510-15-6 4.74 PCB 116 (d5) Endrin 72-20-8 5.20 PCB 116 (d5) p,p'-DDD 72-54-8 6.02 PCB 116 (d5) Endosulfan II 33213-65-9 3.83 PCB 116 (d5) p,p'-DDT 50-29-3 6.36 PCB 116 (d5) Endrin aldehyde 7421-93-4 5.20 PCB 116 (d5) Bifenthrin 82657-04-3 6.00 PCB 116 (d5) Endosulfan sulfate 1031-07-8 3.66 PCB 116 (d5) L-Cyhalothrin 91465-08-6 6.80 PCB 156 (d3) Captafol 2425-06-1 3.80 PCB 156 (d3) Methoxychlor 72-43-5 4.95 PCB 156 (d3) Mirex 2385-85-5 5.28 PCB 156 (d3) Endrin ketone 53494-70-5 5.20 PCB 156 (d3) Imidan 732-11-6 2.95 PCB 156 (d3) Cis-permethrin 61949-76-6 6.10 PCB 156 (d3) Trans-permethrin 61949-77-7 6.10 PCB 156 (d3) Acetamiprid 135410-20-7 2.55 PCB 156 (d3) Cypermethrin 52315-07-8 6.60 PCB 156 (d3) Esfenvalerate 66230-04-4 6.22 PCB 156 (d3) Deltamethrin 52918-63-5 6.20 PCB 156 (d3)

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Appendix D Previous Surface Water Sample Results

Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

UPSTREAM

UPSTREAM‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061316‐AM 061416‐AM 061516‐AM 061616‐AM 061716‐AM Sample Date 6/5/16 16:20 6/6/16 10:20 6/6/16 16:00 6/7/16 9:00 6/7/16 15:00 6/8/16 10:20 6/8/16 15:45 6/9/16 10:45 6/8/16 16:05 6/10/16 8:50 6/11/16 8:20 6/12/16 8:18 6/13/16 7:12 6/14/16 7:12 6/15/16 11:00 6/16/16 9:40 6/17/16 7:00 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 1,2,3‐Trichlorobenzene 2.30 J 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4‐Trichlorobenzene 0.85 J 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U Chloroform 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U Dibromochloromethane 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U Dibromomethane 0.34 UJ 0.34 UJ 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 1.40 J 0.49 U 0.49 U 0.49 U 2 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Methyl tert‐butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Naphthalene 1.00 J 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U n‐Butylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U N‐Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U o‐Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U

Page 1 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

UPSTREAM

UPSTREAM‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061316‐AM 061416‐AM 061516‐AM 061616‐AM 061716‐AM Sample Date 6/5/16 16:20 6/6/16 10:20 6/6/16 16:00 6/7/16 9:00 6/7/16 15:00 6/8/16 10:20 6/8/16 15:45 6/9/16 10:45 6/8/16 16:05 6/10/16 8:50 6/11/16 8:20 6/12/16 8:18 6/13/16 7:12 6/14/16 7:12 6/15/16 11:00 6/16/16 9:40 6/17/16 7:00 trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.003 U 0.01 J 0.006 U 0.006 U 0.0062 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.006 U 0.0073 U 0.0061 U 0.006 U 0.006 U 0.006 U 0.007 J 0.006 U 2‐Methylnaphthalene 0.0061 U 0.023 J 0.009 U 0.009 U 0.0093 U 0.009 U 0.0092 U 0.009 U 0.009 U 0.009 U 0.011 U 0.0092 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U Acenaphthene 0.0061 U 0.0025 J 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0053 J 0.002 U Acenaphthylene 0.0061 U 0.0024 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0053 J 0.002 U Anthracene 0.0041 U 0.0038 J 0.0044 J 0.003 U 0.0031 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0061 J 0.003 U Benzo[a]anthracene 0.0041 U 0.0031 J 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0068 J 0.002 U Benzo[a]pyrene 0.003 U 0.0036 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0058 J 0.003 U Benzo[b]fluoranthene 0.003 U 0.0097 U 0.008 U 0.008 U 0.0083 U 0.008 U 0.0082 U 0.008 U 0.008 U 0.008 U 0.0098 U 0.0081 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U Benzo[g,h,i]perylene 0.02 U 0.0036 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0058 J 0.003 U Benzo[k]fluoranthene 0.0061 U 0.011 U 0.009 U 0.009 U 0.0093 U 0.009 U 0.0092 U 0.009 U 0.009 U 0.009 U 0.011 U 0.0092 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U Chrysene 0.0061 U 0.0073 U 0.006 U 0.006 U 0.0062 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.006 U 0.0073 U 0.0061 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U Dibenz(a,h)anthracene 0.003 U 0.0024 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0046 J 0.002 U Fluoranthene 0.008 J 0.0068 J 0.0066 J 0.0042 J 0.0026 J 0.002 U 0.0021 U 0.02 U 0.002 U 0.002 U 0.0024 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0097 J 0.002 U Fluorene 0.0061 U 0.0041 J 0.0046 J 0.0036 J 0.0039 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0057 J 0.003 U Indeno[1,2,3‐cd]pyrene 0.0041 U 0.0085 U 0.007 U 0.007 U 0.0072 U 0.007 U 0.0072 U 0.007 U 0.007 U 0.007 U 0.0085 U 0.0071 U 0.007 U 0.007 U 0.007 U 0.0073 J 0.007 U Naphthalene 0.0061 U 0.019 J 0.018 J 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.016 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 0.0097 J 0.011 J 0.011 J 0.012 J 0.0069 J 0.02 U 0.021 U 0.0052 J 0.0056 J 0.004 U 0.0049 U 0.0044 J 0.02 U 0.0066 J 0.004 U 0.0093 J 0.0056 J Pyrene 0.0063 J 0.0062 J 0.0045 J 0.0058 J 0.0041 U 0.004 U 0.0041 U 0.004 U 0.004 U 0.004 U 0.0049 U 0.0041 U 0.004 U 0.004 U 0.004 U 0.01 J 0.004 U NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10‐C24) ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 0.026 J 0.11 U 0.11 U Motor Oil (>C24‐C36) ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 0.029 U 0.029 U 0.029 U Notes: Results shown in bold denote detected concentrations. µg/L = micrograms per Liter mg/L = milligrams per Liter "‐" ‐ Not analyzed. NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 2 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

UPSTREAM DOWNSTREAM

DOWNSTREA Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ M‐060516 Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 062016‐AM 062216‐AM 062716‐AM 070716 071316 072216 080516 081516 082416 090716 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM Sample Date 6/20/16 10:00 6/22/16 8:30 6/27/16 9:20 7/7/16 12:45 7/13/16 10:40 7/22/16 13:05 8/5/16 10:40 8/15/16 15:45 8/24/16 15:15 9/7/16 15:10 6/5/16 17:05 6/6/16 11:00 6/6/16 16:20 6/7/16 9:30 6/7/16 15:30 6/8/16 10:40 6/8/16 16:30 6/9/16 11:00 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.65 J 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.47 J 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.24 J 0.21 U 0.25 J 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U Chloroform 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U Dibromochloromethane 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 UJ 0.34 UJ 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Methyl tert‐butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.30 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Naphthalene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U n‐Butylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U N‐Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U o‐Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U

Page 3 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

UPSTREAM DOWNSTREAM

DOWNSTREA Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ M‐060516 Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 062016‐AM 062216‐AM 062716‐AM 070716 071316 072216 080516 081516 082416 090716 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM Sample Date 6/20/16 10:00 6/22/16 8:30 6/27/16 9:20 7/7/16 12:45 7/13/16 10:40 7/22/16 13:05 8/5/16 10:40 8/15/16 15:45 8/24/16 15:15 9/7/16 15:10 6/5/16 17:05 6/6/16 11:00 6/6/16 16:20 6/7/16 9:30 6/7/16 15:30 6/8/16 10:40 6/8/16 16:30 6/9/16 11:00 trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0062 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.0063 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.003 U 0.006 U 0.012 J 0.008 J 0.007 J 0.006 U 0.006 U 0.006 U 2‐Methylnaphthalene 0.0092 U 0.0091 U 0.009 U 0.0091 U 0.009 U 0.0094 U 0.0092 U 0.009 U 0.0091 U 0.009 U 0.006 U 0.01 J 0.025 J 0.014 J 0.011 J 0.009 U 0.009 U 0.009 U Acenaphthene 0.0021 U 0.002 U 0.002 U 0.002 U 0.02 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.006 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 0.0021 U 0.002 U 0.002 U 0.002 U 0.02 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.006 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 0.0031 U 0.003 U 0.003 U 0.003 U 0.02 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.004 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[a]anthracene 0.0021 U 0.011 J 0.002 U 0.002 U 0.02 U 0.0021 U 0.002 U 0.0046 J 0.002 U 0.007 J 0.004 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.0031 U 0.003 U 0.003 U 0.003 U 0.02 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.0082 U 0.0081 U 0.008 U 0.0081 U 0.008 U 0.0084 U 0.0082 U 0.008 U 0.0081 U 0.008 U 0.003 U 0.008 U 0.008 U 0.008 U 0.009 U 0.008 U 0.008 U 0.008 U Benzo[g,h,i]perylene 0.0031 U 0.003 U 0.003 U 0.003 U 0.02 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.002 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.0092 U 0.0091 U 0.009 U 0.0091 U 0.009 U 0.0094 U 0.0092 U 0.009 U 0.0091 U 0.009 U 0.006 U 0.009 U 0.009 U 0.009 U 0.01 U 0.009 U 0.009 U 0.009 U Chrysene 0.0062 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.0063 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U Dibenz(a,h)anthracene 0.0021 U 0.002 U 0.002 U 0.002 U 0.02 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.003 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.0021 U 0.002 U 0.002 U 0.002 U 0.02 U 0.0021 U 0.002 U 0.0043 J 0.002 U 0.004 J 0.004 U 0.002 U 0.003 J 0.003 J 0.003 J 0.002 U 0.002 U 0.002 U Fluorene 0.0031 U 0.003 U 0.003 U 0.003 U 0.02 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.006 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3‐cd]pyrene 0.0072 U 0.0071 U 0.007 U 0.0071 U 0.007 U 0.0073 U 0.0072 U 0.007 U 0.0071 U 0.007 U 0.004 U 0.007 U 0.007 U 0.007 U 0.008 U 0.007 U 0.007 U 0.007 U Naphthalene 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.015 J 0.013 U 0.013 U 0.013 U 0.013 U 0.006 U 0.013 U 0.035 J 0.014 U 0.016 J 0.013 U 0.013 U 0.013 U Phenanthrene 0.0041 U 0.02 U 0.011 J 0.0052 J 0.02 U 0.0055 J 0.005 J 0.0041 J 0.0047 J 0.008 J 0.006 U 0.004 U 0.008 J 0.007 J 0.01 J 0.02 U 0.02 U 0.004 U Pyrene 0.0041 U 0.0041 U 0.004 U 0.0041 U 0.02 U 0.0042 U 0.0041 U 0.0064 J 0.0041 U 0.004 J 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 0.049 J 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10‐C24) 0.031 J 0.039 J 0.11 U 0.023 J 0.027 J 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ Motor Oil (>C24‐C36) 0.029 U 0.03 U 0.03 U 0.03 U 0.031 U 0.03 U 0.26 U 0.03 U 0.03 U 0.029 U ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ Notes: Results shown in bold denote detected concentrations. µg/L = micrograms per Liter mg/L = milligrams per Liter "‐" ‐ Not analyzed. NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 4 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

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Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061316‐AM 061416‐AM 061516‐AM 061616‐AM 061716‐AM 062016‐AM 062216‐AM 062716‐AM 070716 071316 072216 080516 081516 082416 Sample Date 6/9/16 16:20 6/10/16 9:00 6/11/16 8:35 6/12/16 8:30 6/13/16 7:21 6/14/16 7:20 6/15/16 11:10 6/16/16 9:50 6/17/16 7:10 6/20/16 10:20 6/22/16 8:45 6/27/16 9:40 7/7/16 12:55 7/13/16 11:00 7/22/16 13:20 8/5/16 10:50 8/15/16 16:00 8/24/16 15:30 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2.8 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.95 J 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.19 J 0.16 U 0.16 U 0.16 U 0.16 U 1 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.31 J 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.22 J 0.22 J 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.4 U 0.4 U Chloroform 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U Dibromochloromethane 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 1.5 J 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U Methyl tert‐butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U Naphthalene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1J 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U n‐Butylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.31 J 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U N‐Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 J 0.13 U 0.13 U 0.13 U 3.00 U 0.13 U 0.13 U o‐Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.33 J 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U

Page 5 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

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Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061316‐AM 061416‐AM 061516‐AM 061616‐AM 061716‐AM 062016‐AM 062216‐AM 062716‐AM 070716 071316 072216 080516 081516 082416 Sample Date 6/9/16 16:20 6/10/16 9:00 6/11/16 8:35 6/12/16 8:30 6/13/16 7:21 6/14/16 7:20 6/15/16 11:10 6/16/16 9:50 6/17/16 7:10 6/20/16 10:20 6/22/16 8:45 6/27/16 9:40 7/7/16 12:55 7/13/16 11:00 7/22/16 13:20 8/5/16 10:50 8/15/16 16:00 8/24/16 15:30 trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.0064 U 0.006 U 0.006 U 0.006 U 0.006 U 2‐Methylnaphthalene 0.009 U 0.009 U 0.009 U 0.009 U 0.0091 U 0.0089 U 0.009 U 0.009 U 0.009 U 0.009 U 0.0093 U 0.009 U 0.009 U 0.0096 U 0.009 U 0.009 U 0.0091 U 0.009 U Acenaphthene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.021 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.014 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[a]anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0022 J 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.0079 U 0.008 U 0.008 U 0.008 U 0.008 U 0.0083 U 0.008 U 0.008 U 0.0085 U 0.008 U 0.008 U 0.0081 U 0.008 U Benzo[g,h,i]perylene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.009 U 0.009 U 0.009 U 0.009 U 0.0091 U 0.0089 U 0.009 U 0.009 U 0.01 J 0.009 U 0.0093 U 0.009 U 0.009 U 0.0096 U 0.009 U 0.009 U 0.0091 U 0.009 U Chrysene 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.0064 U 0.006 U 0.006 U 0.006 U 0.006 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0062 J 0.002 U 0.0052 J 0.002 U 0.002 U 0.0027 J 0.002 U 0.002 U 0.021 U 0.002 U 0.002 U 0.002 U 0.002 U Fluorene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3‐cd]pyrene 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.0069 U 0.007 U 0.007 U 0.007 U 0.007 U 0.0072 U 0.007 U 0.007 U 0.0075 U 0.007 U 0.007 U 0.0071 U 0.007 U Naphthalene 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.014 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 0.005 J 0.004 U 0.0045 J 0.0052 J 0.004 U 0.0069 J 0.004 U 0.0051 J 0.0055 J 0.004 U 0.0041 U 0.005 J 0.005 J 0.0043 U 0.004 U 0.0041 J 0.004 U 0.004 U Pyrene 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.0049 J 0.004 U 0.005 J 0.004 U 0.004 U 0.0041 U 0.004 U 0.004 U 0.0043 U 0.004 U 0.004 U 0.004 U 0.004 U NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10‐C24) ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 0.021 J 0.11 U 0.11 U 0.023 J 0.035 J 0.11 U 0.03 J 0.026 J 0.11 U 0.12 U 0.11 U 0.11 U Motor Oil (>C24‐C36) ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 0.029 U 0.029 U 0.029 U 0.029 U 0.03 U 0.03 U 0.029 U 0.031 U 0.03 U 0.26 U 0.03 U 0.03 U Notes: Results shown in bold denote detected concentrations. µg/L = micrograms per Liter mg/L = milligrams per Liter "‐" ‐ Not analyzed. NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 6 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

DOWN OUTFALL AREA STREAM

Downstream‐ SOURCE‐ Source‐060616‐Source‐060716‐Source‐060716‐Source‐060816‐Source‐060816‐Source‐060916‐Source‐060916‐Source‐061016‐Source‐061116‐Source‐061216‐ Source‐061316‐ Sample ID 090716 060516 Source‐060616 PM AM PM AM PM AM PM AM AM AM AM Source‐061416‐AM Source‐061516‐AM Source‐061616‐AM Sample Date 9/7/16 15:25 6/5/16 16:30 6/6/16 10:40 6/6/16 16:00 6/7/16 9:10 6/7/16 15:10 6/8/16 11:00 6/8/16 17:15 6/9/16 11:15 6/9/16 16:35 6/10/16 9:15 6/11/16 8:45 6/12/16 8:45 6/13/16 7:30 6/14/16 7:33 6/15/16 7:33 6/16/16 10:00 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U Chloroform 0.5 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U Dibromochloromethane 0.2 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U Dibromomethane 0.34 U 0.34 UJ 0.34 UJ 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Methyl tert‐butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U Naphthalene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U n‐Butylbenzene 0.3 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U N‐Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U o‐Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U

Page 7 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

DOWN OUTFALL AREA STREAM

Downstream‐ SOURCE‐ Source‐060616‐Source‐060716‐Source‐060716‐Source‐060816‐Source‐060816‐Source‐060916‐Source‐060916‐Source‐061016‐Source‐061116‐Source‐061216‐ Source‐061316‐ Sample ID 090716 060516 Source‐060616 PM AM PM AM PM AM PM AM AM AM AM Source‐061416‐AM Source‐061516‐AM Source‐061616‐AM Sample Date 9/7/16 15:25 6/5/16 16:30 6/6/16 10:40 6/6/16 16:00 6/7/16 9:10 6/7/16 15:10 6/8/16 11:00 6/8/16 17:15 6/9/16 11:15 6/9/16 16:35 6/10/16 9:15 6/11/16 8:45 6/12/16 8:45 6/13/16 7:30 6/14/16 7:33 6/15/16 7:33 6/16/16 10:00 trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.006 U 0.0048 J 0.013 J 0.01 J 0.0061 J 0.0097 J 0.0067 U 0.006 U 0.006 U 0.006 U 0.0084 J 0.006 U 0.006 U 0.013 J 0.006 U 0.006 U 0.006 U 2‐Methylnaphthalene 0.0091 U 0.0063 U 0.021 J 0.017 J 0.013 J 0.014 J 0.01 U 0.009 U 0.009 U 0.009 U 0.0091 J 0.009 U 0.009 U 0.03 U 0.009 U 0.009 U 0.009 U Acenaphthene 0.002 U 0.0063 U 0.002 U 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0031 J 0.002 U 0.002 U 0.002 U Acenaphthylene 0.002 U 0.0063 U 0.002 U 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0022 J 0.002 U 0.002 U 0.002 U Anthracene 0.003 U 0.0042 U 0.003 U 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[a]anthracene 0.0054 J 0.0042 U 0.002 UJ 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 J 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 J Benzo[a]pyrene 0.003 U 0.0031 U 0.003 UJ 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.0081 U 0.0031 U 0.008 UJ 0.0093 U 0.008 U 0.008 U 0.009 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U Benzo[g,h,i]perylene 0.003 U 0.021 U 0.003 U 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.0091 U 0.0063 U 0.009 U 0.01 U 0.009 U 0.009 U 0.01 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U Chrysene 0.006 U 0.0063 U 0.006 UJ 0.007 U 0.006 U 0.006 U 0.0067 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U Dibenz(a,h)anthracene 0.002 U 0.021 U 0.002 U 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.0042 U 0.002 UJ 0.0025 J 0.0025 J 0.002 U 0.022 U 0.02 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.02 U 0.002 U 0.002 U 0.005 J Fluorene 0.003 U 0.0063 U 0.003 U 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0062 J 0.003 U 0.003 U 0.003 U Indeno[1,2,3‐cd]pyrene 0.007 U 0.0043 J 0.007 U 0.0081 U 0.007 U 0.007 U 0.0079 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U Naphthalene 0.013 U 0.0063 U 0.013 U 0.025 J 0.013 U 0.013 U 0.015 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 J 0.013 U 0.013 U 0.013 U Phenanthrene 0.0045 J 0.0063 U 0.004 U 0.006 J 0.0081 J 0.004 U 0.022 U 0.02 U 0.004 U 0.006 J 0.02 U 0.0048 J 0.0043 J 0.02 U 0.0071 J 0.004 J 0.0051 J Pyrene 0.004 U 0.0042 U 0.004 UJ 0.0046 U 0.004 U 0.004 U 0.022 U 0.02 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.0049 J NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10‐C24) 0.11 U ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 0.029 J 0.11 U Motor Oil (>C24‐C36) 0.03 U ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 0.029 U 0.029 U Notes: Results shown in bold denote detected concentrations. µg/L = micrograms per Liter mg/L = milligrams per Liter "‐" ‐ Not analyzed. NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 8 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

OUTFALL AREA

Sample ID Source‐061716‐AM Source‐062016‐AM Source‐062216‐AM Source‐062716‐AM Source‐070716 Source‐071316 Source‐072216 Source‐080516 Source‐081516 Source‐082416 Source‐090716 CR‐BCH‐061016 Sample Date 6/17/16 7:25 6/20/16 10:35 6/22/16 9:00 6/27/16 10:10 7/7/16 13:05 7/13/16 11:15 7/22/16 13:35 8/5/16 11:00 8/15/16 16:15 8/24/16 15:40 9/7/16 15:55 6/10/16 11:35 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.5 U 0.5 U 0.5 U 0.5 U 0.50 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.34 J 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.48 J 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U 0.2 U 0.2 U 0.20 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.40 U 0.4 U 0.4 U 0.4 U 0.4 U 0.40 U Chloroform 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.50 U 0.5 U 0.5 U 0.5 U 0.5 U 0.50 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U 0.2 U 0.2 U 0.20 U Dibromochloromethane 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.20 U 0.2 U 0.2 U 0.2 U 0.2 U 0.20 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.27 J 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U Methyl tert‐butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.83 J 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U Naphthalene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U n‐Butylbenzene 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.30 U 0.3 U 0.3 U 0.3 U 0.3 U 0.30 U N‐Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U o‐Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 3 U 0.27 U 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.63 J 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U

Page 9 of 10 Table D‐1. Columbia River Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report

OUTFALL AREA

Sample ID Source‐061716‐AM Source‐062016‐AM Source‐062216‐AM Source‐062716‐AM Source‐070716 Source‐071316 Source‐072216 Source‐080516 Source‐081516 Source‐082416 Source‐090716 CR‐BCH‐061016 Sample Date 6/17/16 7:25 6/20/16 10:35 6/22/16 9:00 6/27/16 10:10 7/7/16 13:05 7/13/16 11:15 7/22/16 13:35 8/5/16 11:00 8/15/16 16:15 8/24/16 15:40 9/7/16 15:55 6/10/16 11:35 trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.25 0.017 J 0.012 J 0.006 U 0.006 U 0.006 U 0.0061 U 0.0061 U 0.0061 U 0.006 U 0.006 U 0.0061 U 2‐Methylnaphthalene 0.27 0.02 J 0.021 J 0.0091 U 0.009 U 0.009 U 0.0092 U 0.0092 U 0.0091 U 0.009 U 0.009 U 0.0092 U Acenaphthene 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.02 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 0.01 J 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.02 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U Benzo[a]anthracene 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.004 J 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U Benzo[b]fluoranthene 0.008 U 0.0081 U 0.0082 U 0.008 U 0.008 U 0.008 U 0.0082 U 0.0081 U 0.0081 U 0.008 U 0.008 U 0.0081 U Benzo[g,h,i]perylene 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U Benzo[k]fluoranthene 0.009 U 0.0091 U 0.0093 U 0.0091 U 0.009 U 0.009 U 0.0092 U 0.0092 U 0.0091 U 0.009 U 0.009 U 0.0092 U Chrysene 0.006 U 0.0061 U 0.0062 U 0.006 U 0.006 U 0.006 U 0.0061 U 0.0061 U 0.0061 U 0.006 U 0.006 U 0.0061 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.002 U 0.0028 J 0.002 U 0.002 U 0.02 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.02 U Fluorene 0.02 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U Indeno[1,2,3‐cd]pyrene 0.007 U 0.0071 U 0.0072 U 0.007 U 0.007 U 0.007 U 0.0072 U 0.0071 U 0.0071 U 0.007 U 0.007 U 0.0071 U Naphthalene 0.097 0.016 J 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 0.044 0.0066 J 0.021 U 0.0068 J 0.0058 J 0.02 U 0.0042 J 0.0041 U 0.004 U 0.004 U 0.0085 J 0.02 U Pyrene 0.004 U 0.004 U 0.0041 U 0.004 U 0.004 U 0.02 U 0.0041 U 0.0041 U 0.004 U 0.004 U 0.004 U 0.0041 U NWTPH (mg/L) Gasoline 0.028 J 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10‐C24) 0.11 U 0.07 J 0.033 J 0.11 U 0.034 J 0.024 J 0.11 U 0.11 U 0.12 U 0.11 U 0.11 U ‐‐ Motor Oil (>C24‐C36) 0.042 J 0.048 J 0.029 U 0.029 U 0.03 U 0.03 U 0.03 U 0.26 U 0.031 U 0.03 U 0.029 U ‐‐

Notes: Results shown in bold denote detected concentrations. µg/L = micrograms per Liter mg/L = milligrams per Liter "‐" ‐ Not analyzed. NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 10 of 10 Table D‐2. Rock Creek Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK UPSTREAM Sample ID RC‐UP‐061016 RC‐UP‐061216‐AM RC‐UP‐061416‐AM RC‐UP‐061516‐AM RC‐UP‐061616‐AM RC‐UP‐062716‐AM RC‐UP‐070716 RC‐UP‐080516 RC‐UP‐090716 Sample Date 6/10/16 12:35 6/12/16 9:06 6/14/16 8:43 6/15/16 11:40 6/16/16 10:15 6/27/16 9:50 7/7/16 13:15 8/5/16 11:15 9/7/16 15:35 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 J 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 3 U 0.26 U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Methyl tert‐butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Naphthalene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 2 U 0.26 U n‐Butylbenzene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U N‐Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 3 U 0.13 U o‐Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 3 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 3 U 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U

Page 1 of 4 Table D‐2. Rock Creek Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK UPSTREAM Sample ID RC‐UP‐061016 RC‐UP‐061216‐AM RC‐UP‐061416‐AM RC‐UP‐061516‐AM RC‐UP‐061616‐AM RC‐UP‐062716‐AM RC‐UP‐070716 RC‐UP‐080516 RC‐UP‐090716 Sample Date 6/10/16 12:35 6/12/16 9:06 6/14/16 8:43 6/15/16 11:40 6/16/16 10:15 6/27/16 9:50 7/7/16 13:15 8/5/16 11:15 9/7/16 15:35 trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0076 J 0.006 U 0.0079 J 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0061 U 2‐Methylnaphthalene 0.0097 J 0.0091 U 0.0091 U 0.009 U 0.009 U 0.0091 U 0.009 U 0.009 U 0.0091 U Acenaphthene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[a]anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 J 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.008 U 0.0081 U 0.0081 U 0.008 U 0.008 U 0.0081 U 0.008 U 0.008 U 0.0081 U Benzo[g,h,i]perylene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.009 U 0.0091 U 0.0091 U 0.009 U 0.009 U 0.0091 U 0.009 U 0.009 U 0.0091 U Chrysene 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0061 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.002 U 0.002 U 0.002 U 0.0058 J 0.002 U 0.002 U 0.002 U 0.0085 J Fluorene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3‐cd]pyrene 0.007 U 0.007 U 0.0071 U 0.007 U 0.007 U 0.0071 U 0.007 U 0.007 U 0.0071 U Naphthalene 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 0.02 U 0.0042 J 0.011 J 0.0059 J 0.0058 J 0.0071 J 0.007 J 0.0056 J 0.013 J Pyrene 0.004 U 0.004 U 0.004 U 0.004 U 0.0052 J 0.004 U 0.004 U 0.004 U 0.0046 J NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10‐C24) ‐‐ ‐‐ ‐‐ 0.038 J 0.11 U 0.11 U 0.034 J 0.11 U 0.019 U Motor Oil (>C24‐C36) ‐‐ ‐‐ ‐‐ 0.029 U 0.029 U 0.03 U 0.03 U 0.25 U 0.03 U Notes: Results shown in bold denote detected concentrations. µg/L = micrograms per Liter mg/L = milligrams per Liter "‐" ‐ Not analyzed. NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 2 of 4 Table D‐2. Rock Creek Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK DOWNSTREAM Sample ID RC‐DN‐061016 RC‐DN‐061016‐FD RC‐DN‐061216‐AM RC‐DN‐061416‐AM RC‐DN‐061516‐AM RC‐DN‐061616‐AM RC‐DN‐062716‐AM RC‐DN‐070716 RC‐DN‐080516 RC‐DN090716 Sample Date 6/10/16 12:05 6/10/16 12:00 6/12/16 9:00 6/14/16 8:38 6/15/16 11:30 6/16/16 10:10 6/27/16 10:00 7/7/16 10:00 8/5/16 11:10 9/7/16 15:45 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Methyl tert‐butyl ether 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Naphthalene 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U n‐Butylbenzene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U N‐Propylbenzene 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U o‐Xylene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 3 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U

Page 3 of 4 Table D‐2. Rock Creek Surface Water Sample Results Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK DOWNSTREAM Sample ID RC‐DN‐061016 RC‐DN‐061016‐FD RC‐DN‐061216‐AM RC‐DN‐061416‐AM RC‐DN‐061516‐AM RC‐DN‐061616‐AM RC‐DN‐062716‐AM RC‐DN‐070716 RC‐DN‐080516 RC‐DN090716 Sample Date 6/10/16 12:05 6/10/16 12:00 6/12/16 9:00 6/14/16 8:38 6/15/16 11:30 6/16/16 10:10 6/27/16 10:00 7/7/16 10:00 8/5/16 11:10 9/7/16 15:45 trans‐1,2‐Dichloroethene / 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0061 U 0.0061 U 0.006 U 0.006 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.006 U 0.006 U 2‐Methylnaphthalene 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.009 U 0.0091 U 0.0091 U 0.009 U 0.009 U Acenaphthene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0052 J 0.003 U 0.003 U 0.003 U Benzo[a]anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0034 J 0.022 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.014 J 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.0081 U 0.0081 U 0.0081 U 0.0081 U 0.0081 U 0.008 U 0.024 0.0081 U 0.008 U 0.008 U Benzo[g,h,i]perylene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.029 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.009 U 0.024 J 0.0091 U 0.009 U 0.009 U Chrysene 0.0061 U 0.0061 U 0.006 U 0.006 U 0.0061 U 0.006 U 0.027 0.006 U 0.006 U 0.006 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.03 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.02 U 0.002 U 0.002 U 0.002 U 0.005 J 0.013 J 0.002 U 0.002 U 0.0071 J Fluorene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3‐cd]pyrene 0.0071 U 0.0071 U 0.0071 U 0.0071 U 0.0071 U 0.007 U 0.018 J 0.007 U 0.007 U 0.007 U Naphthalene 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 0.02 U 0.02 U 0.0055 J 0.0083 J 0.0048 J 0.0066 J 0.01 J 0.0069 J 0.004 J 0.0099 J Pyrene 0.0041 U 0.004 U 0.004 U 0.004 U 0.0041 U 0.0041 J 0.013 J 0.004 U 0.004 U 0.0047 J NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U 0.027 U #2 Diesel (C10‐C24) ‐‐ ‐‐ ‐‐ ‐‐ 0.022 J 0.11 U 0.11 U 0.033 J 0.11 U 0.11 U Motor Oil (>C24‐C36) ‐‐ ‐‐ ‐‐ ‐‐ 0.029 U 0.029 U 0.03 U 0.029 U 0.26 U 0.03 U Notes: Results shown in bold denote detected concentrations. µg/L = micrograms per Liter mg/L = milligrams per Liter "‐" ‐ Not analyzed. NWTPH = Northwest Total Petroleum Hydrocarbon Analytical Method Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value. U ‐ Analyte was not detected above the method detection limit (MDL).

Page 4 of 4 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report UPSTREAM UPSTREAM‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 16:20 6/6/16 10:20 6/6/16 16:00 6/7/16 9:00 6/7/16 15:10 6/8/16 15:45 6/8/16 15:45 6/9/16 10:45 6/8/16 16:05 6/10/16 8:50 6/11/16 8:20 6/12/16 8:18 Method Battelle Standard Operating Procedures 5‐245 (PIANO analysis) (µg/L) n‐Pentane ND ND ND ND ND ND ND ND ND ND ND ND n‐Hexane ND ND ND ND ND ND ND ND ND ND ND ND n‐Heptane ND ND ND ND ND ND ND ND ND ND ND ND n‐Octane ND ND ND ND ND ND ND ND ND ND ND ND n‐Nonane ND ND ND ND ND ND ND ND ND ND ND ND n‐Decane ND ND ND ND ND ND ND ND ND ND ND ND n‐Undecane ND ND ND ND ND ND ND ND ND ND ND ND n‐Dodecane 0.05 J ND ND 0.05 J ND ND ND ND ND ND ND ND Isopentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylpentane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2,3‐trimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylhexane ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2,4‐Trimethylpentane/1‐heptene ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,5‐Dimethylhexane/2,2,3‐trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,3,4‐Trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,3,3‐Trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND 4‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,2,4‐Trimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,6‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,5‐dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐dimethylheptane/3,5‐dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3,4‐Dimethylheptane (D) ND ND ND ND ND ND ND ND ND ND ND ND

Page 1 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report UPSTREAM UPSTREAM‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 16:20 6/6/16 10:20 6/6/16 16:00 6/7/16 9:00 6/7/16 15:10 6/8/16 15:45 6/8/16 15:45 6/9/16 10:45 6/8/16 16:05 6/10/16 8:50 6/11/16 8:20 6/12/16 8:18 3,4‐Dimethylheptane (L) ND ND ND ND ND ND ND ND ND ND ND ND 4‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐Diethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 2‐methylnonane ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylnonane ND ND ND ND ND ND ND ND ND ND ND ND Benzene ND ND ND ND ND ND ND ND ND ND ND ND Toluene ND ND ND 0.02 J ND ND ND ND 0.03 J 0.01 J ND ND Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND m‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND p‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND o‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND Isopropylbenzene ND ND ND ND ND ND ND ND ND ND ND ND Propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐3‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐4‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3,5‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐2‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐butylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND isobutylbenzene ND ND ND ND ND ND ND ND ND ND ND ND sec‐Butylbenzene ND ND ND ND ND ND ND ND ND ND ND ND m‐cymene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND p‐Cymene ND ND ND ND ND ND ND ND ND ND ND ND Indane ND ND ND ND ND ND ND ND ND ND ND ND o‐cymene ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Diethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐methyl‐3‐n‐propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐methyl‐4‐n‐propylbenzene/1,4‐Diethylbenz ND ND ND ND ND ND ND ND ND ND ND ND butyl benzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Dimethyl‐5‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Diethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐2‐n‐Propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,4‐dimethyl‐2‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐ethyl‐2,4‐dimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND

Page 2 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report UPSTREAM UPSTREAM‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 16:20 6/6/16 10:20 6/6/16 16:00 6/7/16 9:00 6/7/16 15:10 6/8/16 15:45 6/8/16 15:45 6/9/16 10:45 6/8/16 16:05 6/10/16 8:50 6/11/16 8:20 6/12/16 8:18 1,2‐Dimethyl‐4‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Dimethyl‐2‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐dimethyl‐3‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4,5‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 2‐methylbutylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3,5‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐2‐methylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3,4‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND n‐Pentylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐3,5‐dimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐4‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3,5‐triethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4‐triethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND n‐hexylbenzene ND ND ND ND ND ND ND ND ND ND ND ND Cyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Methylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Cyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1,1‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND cis‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Methylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,3‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,4‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1‐ethyl‐1‐methylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ccc‐1,2,3‐trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Isopropylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND cis‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND Ethylcyclohexane/n‐propylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ccc‐1,3,5‐trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1,1,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1,1,2‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND isobutylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Isopropylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND n‐Butylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND isobutylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND

Page 3 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report UPSTREAM UPSTREAM‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 16:20 6/6/16 10:20 6/6/16 16:00 6/7/16 9:00 6/7/16 15:10 6/8/16 15:45 6/8/16 15:45 6/9/16 10:45 6/8/16 16:05 6/10/16 8:50 6/11/16 8:20 6/12/16 8:18 tert‐1‐methyl‐2‐propylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐methyl‐2‐(4MP)cyclopentane ND ND ND ND ND ND ND ND ND ND ND ND 3‐methyl‐1‐butene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyl‐1‐Butene ND ND ND ND ND ND ND ND ND ND ND ND 2‐methyl‐1,3‐butadiene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND 4‐methylpentene‐1NDNDND ND ND ND ND ND ND ND ND ND 1‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylpentene‐2NDNDND ND ND ND ND ND ND ND ND ND cis‐2‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyl‐1‐Hexene/trans‐1,2‐dimethylcyclop ND ND ND ND ND ND ND ND ND ND ND ND trans‐3‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND cis‐3‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Octene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Octene ND ND ND ND ND ND ND ND ND ND ND ND Cis‐2‐octene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND trans‐3‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND cis‐3‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Decene ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethane ND ND ND ND ND ND ND ND ND ND ND ND 1,2 Dibromoethane ND ND ND ND ND ND ND ND ND ND ND ND MMT ND ND ND ND ND ND ND ND ND ND ND ND ethanol ND ND ND ND ND ND ND ND ND ND ND ND t‐Butanol ND ND ND ND ND ND ND ND ND ND ND ND Methyl tert butyl ether ND ND ND ND ND ND ND ND ND ND ND ND Di‐isopropyl ether ND ND ND ND ND ND ND ND ND ND ND ND Ethyl tert butyl ether ND ND ND ND ND ND ND ND ND ND ND ND Tert amyl methyl ether ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethylene (trans) ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethylene (cis) ND ND ND ND ND ND ND ND ND ND ND ND 1,1,1‐Trichloroethane ND ND ND ND ND ND ND ND ND ND ND ND Trichloroethylene ND ND ND ND ND ND ND ND ND ND ND ND Tetrachloroethylene ND ND ND ND ND ND ND ND ND ND ND ND

Page 4 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report UPSTREAM UPSTREAM‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Upstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 16:20 6/6/16 10:20 6/6/16 16:00 6/7/16 9:00 6/7/16 15:10 6/8/16 15:45 6/8/16 15:45 6/9/16 10:45 6/8/16 16:05 6/10/16 8:50 6/11/16 8:20 6/12/16 8:18 Styrene ND ND ND ND ND ND ND ND ND ND ND ND Thiophene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylthiophene ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylthiophene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Ethylthiophene ND ND ND ND ND ND ND ND ND ND ND ND Benzo(b)thiophene ND ND ND ND ND ND ND ND ND ND ND ND Naphthalene ND ND ND ND ND ND ND ND 0.06 J ND ND ND Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit ND = Analyte was not detected above the MDL Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value.

Page 5 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report DOWNSTREAM DOWNSTREAM‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 17:05 6/6/16 11:00 6/6/16 16:20 6/7/16 9:30 6/7/16 15:30 6/8/16 10:40 6/8/16 16:30 6/9/16 11:00 6/9/16 16:20 6/10/16 9:00 6/11/16 8:35 6/12/16 8:30 Method Battelle Standard Operating Procedures 5‐245 (PIANO analysis) (µg/L) n‐Pentane ND ND ND ND ND ND ND ND ND ND ND ND n‐Hexane ND ND ND ND ND ND ND ND ND ND ND ND n‐Heptane ND ND ND ND ND ND ND ND ND ND ND ND n‐Octane ND ND ND ND ND ND ND ND ND ND ND ND n‐Nonane ND ND ND ND ND ND ND ND ND ND ND ND n‐Decane ND ND ND ND ND ND ND ND ND ND ND ND n‐Undecane ND ND ND ND ND ND ND ND ND ND ND ND n‐Dodecane ND ND ND ND ND ND ND ND ND ND ND ND Isopentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylpentane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2,3‐trimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylhexane ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2,4‐Trimethylpentane/1‐heptene ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,5‐Dimethylhexane/2,2,3‐trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,3,4‐Trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,3,3‐Trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND 4‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,2,4‐Trimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,6‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,5‐dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐dimethylheptane/3,5‐dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND 3,4‐Dimethylheptane (D) ND ND ND ND ND ND ND ND ND ND ND ND

Page 6 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report DOWNSTREAM DOWNSTREAM‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 17:05 6/6/16 11:00 6/6/16 16:20 6/7/16 9:30 6/7/16 15:30 6/8/16 10:40 6/8/16 16:30 6/9/16 11:00 6/9/16 16:20 6/10/16 9:00 6/11/16 8:35 6/12/16 8:30 3,4‐Dimethylheptane (L) ND ND ND ND ND ND ND ND ND ND ND ND 4‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐Diethylpentane ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 2‐methylnonane ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethyloctane ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylnonane ND ND ND ND ND ND ND ND ND ND ND ND Benzene ND ND ND ND ND ND ND ND ND ND ND ND Toluene ND 0.03 J ND 0.02 J ND ND ND ND 0.02 J ND ND ND Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND m‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND p‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND o‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND Isopropylbenzene ND ND ND ND ND ND ND ND ND ND ND ND Propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐3‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐4‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3,5‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐2‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐butylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND isobutylbenzene ND ND ND ND ND ND ND ND ND ND ND ND sec‐Butylbenzene ND ND ND ND ND ND ND ND ND ND ND ND m‐cymene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND p‐Cymene ND ND ND ND ND ND ND ND ND ND ND ND Indane ND ND ND ND ND ND ND ND ND ND ND ND o‐cymene ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Diethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐methyl‐3‐n‐propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐methyl‐4‐n‐propylbenzene/1,4‐Diethylbenz ND ND ND ND ND ND ND ND ND ND ND ND butyl benzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Dimethyl‐5‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Diethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐2‐n‐Propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,4‐dimethyl‐2‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1‐ethyl‐2,4‐dimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND

Page 7 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report DOWNSTREAM DOWNSTREAM‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 17:05 6/6/16 11:00 6/6/16 16:20 6/7/16 9:30 6/7/16 15:30 6/8/16 10:40 6/8/16 16:30 6/9/16 11:00 6/9/16 16:20 6/10/16 9:00 6/11/16 8:35 6/12/16 8:30 1,2‐Dimethyl‐4‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Dimethyl‐2‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐dimethyl‐3‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4,5‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 2‐methylbutylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3,5‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐2‐methylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3,4‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND n‐Pentylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐3,5‐dimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐4‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,3,5‐triethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4‐triethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND n‐hexylbenzene ND ND ND 0.01 J ND ND ND ND ND ND ND ND Cyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Methylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Cyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1,1‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND cis‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Methylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,3‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,4‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1‐ethyl‐1‐methylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ccc‐1,2,3‐trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Isopropylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND cis‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND Ethylcyclohexane/n‐propylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ccc‐1,3,5‐trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1,1,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND 1,1,2‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND isobutylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND Isopropylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND n‐Butylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND isobutylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND

Page 8 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report DOWNSTREAM DOWNSTREAM‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 17:05 6/6/16 11:00 6/6/16 16:20 6/7/16 9:30 6/7/16 15:30 6/8/16 10:40 6/8/16 16:30 6/9/16 11:00 6/9/16 16:20 6/10/16 9:00 6/11/16 8:35 6/12/16 8:30 tert‐1‐methyl‐2‐propylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐methyl‐2‐(4MP)cyclopentane ND ND ND ND ND ND ND ND ND ND ND ND 3‐methyl‐1‐butene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyl‐1‐Butene ND ND ND ND ND ND ND ND ND ND ND ND 2‐methyl‐1,3‐butadiene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND 4‐methylpentene‐1 ND ND ND ND ND ND ND ND ND ND ND ND 1‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylpentene‐2 ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyl‐1‐Hexene/trans‐1,2‐dimethylcyclop ND ND ND ND ND ND ND ND ND ND ND ND trans‐3‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND cis‐3‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Octene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Octene ND ND ND ND ND ND ND ND ND ND ND ND Cis‐2‐octene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND trans‐3‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND cis‐3‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND 1‐Decene ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethane ND ND ND ND ND ND ND ND ND ND ND ND 1,2 Dibromoethane ND ND ND ND ND ND ND ND ND ND ND ND MMT ND ND ND ND ND ND ND ND ND ND ND ND ethanol ND ND ND ND ND ND ND ND ND ND ND ND t‐Butanol ND ND ND ND ND ND ND ND ND ND ND ND Methyl tert butyl ether ND ND ND ND ND ND ND ND ND ND ND ND Di‐isopropyl ether ND ND ND ND ND ND ND ND ND ND ND ND Ethyl tert butyl ether ND ND ND ND ND ND ND ND ND ND ND ND Tert amyl methyl ether ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethylene (trans) ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethylene (cis) ND ND ND ND ND ND ND ND ND ND ND ND 1,1,1‐Trichloroethane ND ND ND ND ND ND ND ND ND ND ND ND Trichloroethylene ND ND ND ND ND ND ND ND ND ND ND ND Tetrachloroethylene ND ND ND ND ND ND ND ND ND ND ND ND

Page 9 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report DOWNSTREAM DOWNSTREAM‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Downstream‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM Sample Date 6/5/16 17:05 6/6/16 11:00 6/6/16 16:20 6/7/16 9:30 6/7/16 15:30 6/8/16 10:40 6/8/16 16:30 6/9/16 11:00 6/9/16 16:20 6/10/16 9:00 6/11/16 8:35 6/12/16 8:30 Styrene ND ND ND ND ND ND ND ND ND ND ND ND Thiophene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylthiophene ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylthiophene ND ND ND ND ND ND ND ND ND ND ND ND 2‐Ethylthiophene ND ND ND ND ND ND ND ND ND ND ND ND Benzo(b)thiophene ND ND ND ND ND ND ND ND ND ND ND ND Naphthalene ND ND ND ND ND ND ND ND ND ND ND ND

Page 10 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report OUTFALL AREA SOURCE‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ CR‐BCH‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061016 Sample Date 6/5/16 16:30 6/6/16 10:40 6/6/16 16:00 6/7/16 9:10 6/7/16 16:00 6/8/16 11:00 6/8/16 17:15 6/9/16 11:15 6/9/16 16:35 6/10/16 9:15 6/11/16 8:45 6/12/16 8:45 6/10/16 11:35 Method Battelle Standard Operating Procedures 5‐245 (PIANO analysis) (µg/L) n‐Pentane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Hexane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Heptane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Octane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Nonane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Decane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Undecane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Dodecane ND ND ND ND ND ND ND ND ND ND ND ND ND Isopentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2,3‐trimethylbutane ND ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylhexane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylhexane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2,4‐Trimethylpentane/1‐heptene ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,5‐Dimethylhexane/2,2,3‐trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,3,4‐Trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,3,3‐Trimethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 4‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethylhexane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2,4‐Trimethylhexane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,4‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,6‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,5‐dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐dimethylheptane/3,5‐dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethylheptane ND ND ND ND ND ND ND ND ND ND ND ND ND 3,4‐Dimethylheptane (D) ND ND ND ND ND ND ND ND ND ND ND ND ND

Page 11 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report OUTFALL AREA SOURCE‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ CR‐BCH‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061016 Sample Date 6/5/16 16:30 6/6/16 10:40 6/6/16 16:00 6/7/16 9:10 6/7/16 16:00 6/8/16 11:00 6/8/16 17:15 6/9/16 11:15 6/9/16 16:35 6/10/16 9:15 6/11/16 8:45 6/12/16 8:45 6/10/16 11:35 3,4‐Dimethylheptane (L) ND ND ND ND ND ND ND ND ND ND ND ND ND 4‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methyloctane ND ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐Diethylpentane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,2‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND ND 3,3‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND ND 2,3‐Dimethyloctane ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐methylnonane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐ethyloctane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylnonane ND ND ND ND ND ND ND ND ND ND ND ND ND Benzene ND ND ND ND ND 0.08 J ND ND ND ND ND ND ND Toluene ND ND ND ND ND 0.07 J ND ND 0.02 J 0.05 J ND 0.01 J 0.08 J Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND m‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND ND p‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND ND o‐Xylene ND ND ND ND ND ND ND ND ND ND ND ND ND Isopropylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND Propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐3‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐4‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,3,5‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐2‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND tert‐butylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND isobutylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND sec‐Butylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND m‐cymene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3‐Trimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND p‐Cymene ND ND ND ND ND ND ND ND ND ND ND ND ND Indane ND ND ND ND ND ND ND ND ND ND ND ND ND o‐cymene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Diethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐methyl‐3‐n‐propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐methyl‐4‐n‐propylbenzene/1,4‐Diethylbenz ND ND ND ND ND ND ND ND ND ND ND ND ND butyl benzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Dimethyl‐5‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Diethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Methyl‐2‐n‐Propylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,4‐dimethyl‐2‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐ethyl‐2,4‐dimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND

Page 12 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report OUTFALL AREA SOURCE‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ CR‐BCH‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061016 Sample Date 6/5/16 16:30 6/6/16 10:40 6/6/16 16:00 6/7/16 9:10 6/7/16 16:00 6/8/16 11:00 6/8/16 17:15 6/9/16 11:15 6/9/16 16:35 6/10/16 9:15 6/11/16 8:45 6/12/16 8:45 6/10/16 11:35 1,2‐Dimethyl‐4‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,3‐Dimethyl‐2‐Ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐dimethyl‐3‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4,5‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐methylbutylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3,5‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐2‐methylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2,3,4‐Tetramethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Pentylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐3,5‐dimethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐butyl‐4‐ethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,3,5‐triethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2,4‐triethylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND n‐hexylbenzene ND ND ND ND ND ND ND ND ND ND ND ND ND Cyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND Methylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND Cyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND 1,1‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND Methylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND ethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,3‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,4‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐ethyl‐1‐methylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND ccc‐1,2,3‐trimethylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND Isopropylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND Ethylcyclohexane/n‐propylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND ccc‐1,3,5‐trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND 1,1,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND 1,1,2‐Trimethylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND isobutylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND Isopropylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND n‐Butylcyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND isobutylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND

Page 13 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report OUTFALL AREA SOURCE‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ CR‐BCH‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061016 Sample Date 6/5/16 16:30 6/6/16 10:40 6/6/16 16:00 6/7/16 9:10 6/7/16 16:00 6/8/16 11:00 6/8/16 17:15 6/9/16 11:15 6/9/16 16:35 6/10/16 9:15 6/11/16 8:45 6/12/16 8:45 6/10/16 11:35 tert‐1‐methyl‐2‐propylcyclohexane ND ND ND ND ND ND ND ND ND ND ND ND ND tert‐1‐methyl‐2‐(4MP)cyclopentane ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐methyl‐1‐butene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyl‐1‐Butene ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐methyl‐1,3‐butadiene ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Pentene ND ND ND ND ND ND ND ND ND ND ND ND ND 4‐methylpentene‐1 ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylpentene‐2 ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Hexene ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methyl‐1‐Hexene/trans‐1,2‐dimethylcyclop ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐3‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐3‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Heptene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Octene ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Octene ND ND ND ND ND ND ND ND ND ND ND ND ND Cis‐2‐octene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐3‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐3‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND ND trans‐2‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND ND cis‐2‐Nonene ND ND ND ND ND ND ND ND ND ND ND ND ND 1‐Decene ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethane ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2 Dibromoethane ND ND ND ND ND ND ND ND ND ND ND ND ND MMT ND ND ND ND ND ND ND ND ND ND ND ND ND ethanol ND ND ND ND ND ND ND ND ND ND ND ND ND t‐Butanol ND ND ND ND ND ND ND ND ND ND ND ND ND Methyl tert butyl ether ND ND ND ND ND ND ND ND ND ND ND ND ND Di‐isopropyl ether ND ND ND ND ND ND ND ND ND ND ND ND ND Ethyl tert butyl ether ND ND ND ND ND ND ND ND ND ND ND ND ND Tert amyl methyl ether ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethylene (trans) ND ND ND ND ND ND ND ND ND ND ND ND ND 1,2‐Dichloroethylene (cis) ND ND ND ND ND ND ND ND ND ND ND ND ND 1,1,1‐Trichloroethane ND ND ND ND ND ND ND ND ND ND ND ND ND Trichloroethylene ND ND ND ND ND ND ND ND ND ND ND ND ND Tetrachloroethylene ND ND ND ND ND ND ND ND ND ND ND ND ND

Page 14 of 15 Table D‐3. Columbia River Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report OUTFALL AREA SOURCE‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ Source‐ CR‐BCH‐ Sample ID 060516 060616 060616‐PM 060716‐AM 060716‐PM 060816‐AM 060816‐PM 060916‐AM 060916‐PM 061016‐AM 061116‐AM 061216‐AM 061016 Sample Date 6/5/16 16:30 6/6/16 10:40 6/6/16 16:00 6/7/16 9:10 6/7/16 16:00 6/8/16 11:00 6/8/16 17:15 6/9/16 11:15 6/9/16 16:35 6/10/16 9:15 6/11/16 8:45 6/12/16 8:45 6/10/16 11:35 Styrene ND ND ND ND ND ND ND ND ND ND ND ND ND Thiophene ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Methylthiophene ND ND ND ND ND ND ND ND ND ND ND ND ND 3‐Methylthiophene ND ND ND ND ND ND ND ND ND ND ND ND ND 2‐Ethylthiophene ND ND ND ND ND ND ND ND ND ND ND ND ND Benzo(b)thiophene ND ND ND ND ND ND ND ND ND ND ND ND ND Naphthalene ND ND ND ND ND ND ND ND ND ND ND ND ND

Page 15 of 15 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK UPSTREAM Sample ID RC‐UP‐061016 RC‐UP‐061216‐AM RC‐UP‐061416‐AM RC‐UP‐061516‐AM RC‐UP‐061616‐AM RC‐UP‐062716‐AM Sample Date 6/10/16 12:35 6/12/16 9:06 6/14/16 8:43 6/15/16 11:40 6/16/16 10:15 6/27/16 9:50 1,1,1‐Trichloroethane ND ND ND ND ND ND 1,1,2‐Trimethylcyclohexane ND ND ND ND ND ND 1,1,4‐Trimethylcyclohexane ND ND ND ND ND ND 1,1‐dimethylcyclopentane ND ND ND ND ND ND 1,2 Dibromoethane ND ND ND ND ND ND 1,2,3,4‐Tetramethylbenzene ND ND ND ND ND ND 1,2,3,5‐Tetramethylbenzene ND ND ND ND ND ND 1,2,3‐Trimethylbenzene ND ND ND ND ND 0.02 J 1,2,4,5‐Tetramethylbenzene ND ND ND ND ND ND 1,2,4‐triethylbenzene ND ND ND ND ND ND 1,2,4‐Trimethylbenzene ND ND ND ND ND ND 1,2‐Dichloroethane ND ND ND ND ND ND 1,2‐Dichloroethylene (cis) ND ND ND ND ND ND 1,2‐Dichloroethylene (trans) ND ND ND ND ND ND 1,2‐Diethylbenzene ND ND ND ND ND ND 1,2‐dimethyl‐3‐ethylbenzene ND ND ND ND ND ND 1,2‐Dimethyl‐4‐Ethylbenzene ND ND ND ND ND ND 1,3,5‐triethylbenzene ND ND ND ND ND ND 1,3,5‐Trimethylbenzene ND ND ND ND ND ND 1,3‐Diethylbenzene ND ND ND ND ND ND 1,3‐Dimethyl‐2‐Ethylbenzene ND ND ND ND ND ND 1,3‐Dimethyl‐5‐Ethylbenzene ND ND ND ND ND ND 1,4‐dimethyl‐2‐ethylbenzene ND ND ND ND ND ND 1‐Decene ND ND ND ND ND ND 1‐ethyl‐1‐methylcyclopentane ND ND ND ND ND ND 1‐ethyl‐2,4‐dimethylbenzene ND ND ND ND ND ND 1‐Hexene ND ND ND ND ND ND 1‐Methyl‐2‐Ethylbenzene ND ND ND ND ND ND 1‐Methyl‐2‐n‐Propylbenzene ND ND ND ND ND ND 1‐Methyl‐3‐Ethylbenzene ND ND ND ND ND ND 1‐methyl‐3‐n‐propylbenzene ND ND ND ND ND ND 1‐Methyl‐4‐Ethylbenzene ND ND ND ND ND ND 1‐methyl‐4‐n‐propylbenzene/1,4‐Diethylbenz ND ND ND ND ND ND 1‐Nonene ND ND ND ND ND ND 1‐Octene ND ND ND ND ND ND 1‐Pentene ND ND ND ND ND ND 2,2,3‐trimethylbutane ND ND ND ND ND ND 2,2,4‐Trimethylhexane ND ND ND ND ND ND 2,2,4‐Trimethylpentane/1‐heptene ND ND ND ND ND ND 2,2‐Dimethylbutane ND ND ND ND ND ND 2,2‐Dimethylheptane ND ND ND ND ND ND 2,2‐dimethylhexane ND ND ND ND ND ND

Page 1 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK UPSTREAM Sample ID RC‐UP‐061016 RC‐UP‐061216‐AM RC‐UP‐061416‐AM RC‐UP‐061516‐AM RC‐UP‐061616‐AM RC‐UP‐062716‐AM Sample Date 6/10/16 12:35 6/12/16 9:06 6/14/16 8:43 6/15/16 11:40 6/16/16 10:15 6/27/16 9:50 1,1,1‐Trichloroethane ND ND ND ND ND ND 2,2‐Dimethyloctane ND ND ND ND ND ND 2,2‐Dimethylpentane ND ND ND ND ND ND 2,3,3‐Trimethylpentane ND ND ND ND ND ND 2,3,4‐Trimethylpentane ND ND ND ND ND ND 2,3‐Dimethylbutane ND ND ND ND ND ND 2,3‐Dimethylheptane ND ND ND ND ND ND 2,3‐Dimethylhexane ND ND ND ND ND ND 2,3‐Dimethyloctane ND ND ND ND ND ND 2,3‐Dimethylpentane ND ND ND ND ND ND 2,4‐Dimethylheptane ND ND ND ND ND ND 2,4‐Dimethylhexane ND ND ND ND ND ND 2,4‐Dimethylpentane ND ND ND ND ND ND 2,5‐dimethylheptane ND ND ND ND ND ND 2,5‐Dimethylhexane/2,2,3‐trimethylpentane ND ND ND ND ND ND 2,6‐Dimethylheptane ND ND ND ND ND ND 2‐Ethylthiophene ND ND ND ND ND ND 2‐methyl‐1,3‐butadiene ND ND ND ND ND ND 2‐Methyl‐1‐Butene ND ND ND ND ND ND 2‐Methyl‐1‐Hexene/trans‐1,2‐dimethylcyclop ND ND ND ND ND ND 2‐methylbutylbenzene ND ND ND ND ND ND 2‐Methylheptane ND ND ND ND ND ND 2‐Methylhexane ND ND ND ND ND ND 2‐methylnonane ND ND ND ND ND ND 2‐Methyloctane ND ND ND ND ND ND 2‐Methylpentane ND ND ND ND ND ND 2‐Methylpentene‐2 ND ND ND ND ND ND 2‐Methylthiophene ND ND ND ND ND ND 3,3‐Diethylpentane ND ND ND ND ND ND 3,3‐dimethylheptane/3,5‐dimethylheptane ND ND ND ND ND ND 3,3‐Dimethyloctane ND ND ND ND ND ND 3,3‐dimethylpentane ND ND ND ND ND ND 3,4‐Dimethylheptane (D) ND ND ND ND ND ND 3,4‐Dimethylheptane (L) ND ND ND ND ND ND 3‐ethylhexane ND ND ND ND ND ND 3‐ethyloctane ND ND ND ND ND ND 3‐ethylpentane ND ND ND ND ND ND 3‐methyl‐1‐butene ND ND ND ND ND ND 3‐Methylheptane ND ND ND ND ND ND 3‐Methylhexane ND ND ND ND ND ND 3‐Methylnonane ND ND ND ND ND ND 3‐Methyloctane ND ND ND ND ND ND

Page 2 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK UPSTREAM Sample ID RC‐UP‐061016 RC‐UP‐061216‐AM RC‐UP‐061416‐AM RC‐UP‐061516‐AM RC‐UP‐061616‐AM RC‐UP‐062716‐AM Sample Date 6/10/16 12:35 6/12/16 9:06 6/14/16 8:43 6/15/16 11:40 6/16/16 10:15 6/27/16 9:50 1,1,1‐Trichloroethane ND ND ND ND ND ND 3‐Methylpentane ND ND ND ND ND ND 3‐Methylthiophene ND ND ND ND ND ND 4‐Methylheptane ND ND ND ND ND ND 4‐Methyloctane ND ND ND ND ND ND 4‐methylpentene‐1 ND ND ND ND ND ND Benzene 0.13 J ND 0.18 J ND ND 0.10 J Benzo(b)thiophene ND ND ND ND ND ND butyl benzene ND ND ND ND ND ND ccc‐1,2,3‐trimethylcyclopentane ND ND ND ND ND ND ccc‐1,3,5‐trimethylcyclohexane ND ND ND ND ND ND cis‐1,2‐dimethylcyclohexane ND ND ND ND ND ND cis‐1,3‐dimethylcyclopentane ND ND ND ND ND ND cis‐2‐Heptene ND ND ND ND ND ND cis‐2‐Hexene ND ND ND ND ND ND cis‐2‐Nonene ND ND ND ND ND ND Cis‐2‐octene ND ND ND ND ND ND cis‐2‐Pentene ND ND ND ND ND ND cis‐3‐Heptene ND ND ND ND ND ND cis‐3‐Nonene ND ND ND ND ND ND ctc‐1,2,3‐Trimethylcyclopentane ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND Cyclohexane 0.06 J ND ND ND ND ND Cyclopentane 0.08 J ND 0.06 J ND ND 0.03 J Di‐isopropyl ether ND ND ND ND ND ND ethanol ND ND ND ND ND ND Ethyl tert butyl ether ND ND ND ND ND ND Ethylbenzene ND ND ND ND ND ND Ethylcyclohexane/n‐propylcyclopentane ND ND ND ND ND ND ethylcyclopentane ND ND ND ND ND ND Indane ND ND ND ND ND ND isobutylbenzene ND ND ND ND ND ND isobutylcyclohexane ND ND ND ND ND ND isobutylcyclopentane ND ND ND ND ND ND Isopentane ND ND ND ND ND ND Isopropylbenzene ND ND ND ND ND ND Isopropylcyclohexane ND ND ND ND ND ND Isopropylcyclopentane ND ND ND ND ND ND m‐cymene ND ND ND ND ND ND

Page 3 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK UPSTREAM Sample ID RC‐UP‐061016 RC‐UP‐061216‐AM RC‐UP‐061416‐AM RC‐UP‐061516‐AM RC‐UP‐061616‐AM RC‐UP‐062716‐AM Sample Date 6/10/16 12:35 6/12/16 9:06 6/14/16 8:43 6/15/16 11:40 6/16/16 10:15 6/27/16 9:50 1,1,1‐Trichloroethane ND ND ND ND ND ND Methyl tert butyl ether ND ND ND ND ND ND Methylcyclohexane ND ND ND ND ND ND Methylcyclopentane 0.05 J ND 0.04 J ND ND 0.04 J MMT ND ND ND ND ND ND m‐Xylene 0.01 J ND 0.01 J ND ND 0.02 J Naphthalene ND ND ND ND ND ND n‐Butylcyclopentane ND ND ND ND ND ND n‐Decane ND ND ND ND ND ND n‐Dodecane ND ND ND ND ND ND n‐Heptane ND ND ND ND ND ND n‐Hexane ND ND ND ND ND ND n‐hexylbenzene ND ND ND ND ND ND n‐Nonane ND ND ND ND ND ND n‐Octane ND ND ND ND ND ND n‐Pentane 0.14 J ND 0.10 J ND ND 0.06 J n‐Pentylbenzene ND ND ND ND ND ND n‐Undecane ND ND ND ND ND ND o‐cymene ND ND ND ND ND ND o‐Xylene ND ND ND ND ND 0.09 J p‐Cymene ND ND ND ND ND ND Propylbenzene ND ND ND ND ND ND p‐Xylene ND ND ND ND ND 0.01 J sec‐Butylbenzene ND ND ND ND ND ND Styrene ND ND ND ND ND ND t‐Butanol ND ND ND ND ND ND Tert amyl methyl ether ND ND ND ND ND ND tert‐1‐butyl‐2‐methylbenzene ND ND ND ND ND ND tert‐1‐butyl‐3,5‐dimethylbenzene ND ND ND ND ND ND tert‐1‐butyl‐4‐ethylbenzene ND ND ND ND ND ND tert‐1‐methyl‐2‐(4MP)cyclopentane ND ND ND ND ND ND tert‐1‐methyl‐2‐propylcyclohexane ND ND ND ND ND ND tert‐butylbenzene ND ND ND ND ND ND Tetrachloroethylene ND ND ND ND ND ND Thiophene ND ND ND ND ND ND Toluene 0.11 J 0.06 J ND ND 0.02 J 0.09 J trans‐1,2‐dimethylcyclohexane ND ND ND ND ND ND trans‐1,3‐dimethylcyclopentane ND ND ND ND ND ND trans‐1,4‐dimethylcyclohexane ND ND ND ND ND ND trans‐2‐Heptene ND ND ND ND ND ND trans‐2‐Hexene ND ND ND ND ND ND trans‐2‐Nonene ND ND ND ND ND ND

Page 4 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK UPSTREAM Sample ID RC‐UP‐061016 RC‐UP‐061216‐AM RC‐UP‐061416‐AM RC‐UP‐061516‐AM RC‐UP‐061616‐AM RC‐UP‐062716‐AM Sample Date 6/10/16 12:35 6/12/16 9:06 6/14/16 8:43 6/15/16 11:40 6/16/16 10:15 6/27/16 9:50 1,1,1‐Trichloroethane ND ND ND ND ND ND trans‐2‐Octene ND ND ND ND ND ND trans‐2‐Pentene ND ND ND ND ND ND trans‐3‐Heptene ND ND ND ND ND ND trans‐3‐Nonene ND ND ND ND ND ND Trichloroethylene ND ND ND ND ND ND Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit ND = Analyte was not detected above the MDL Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value.

Page 5 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK DOWNSTREAM Sample ID RC‐DN‐061016 RC‐DN‐061016‐FD RC‐DN‐061216‐AM RC‐DN‐061416‐AM RC‐DN‐061516‐AM RC‐DN‐061616‐AM RC‐DN‐062716‐AM Sample Date 6/10/16 12:05 6/10/16 12:00 6/12/16 9:00 6/14/16 8:38 6/15/16 11:30 6/16/16 10:10 6/27/16 10:00 1,1,1‐Trichloroethane ND ND ND ND ND ND ND 1,1,2‐Trimethylcyclohexane ND ND ND ND ND ND ND 1,1,4‐Trimethylcyclohexane ND ND ND ND ND ND ND 1,1‐dimethylcyclopentane ND ND ND ND ND ND ND 1,2 Dibromoethane ND ND ND ND ND ND ND 1,2,3,4‐Tetramethylbenzene ND ND ND ND ND ND ND 1,2,3,5‐Tetramethylbenzene ND ND ND ND ND ND ND 1,2,3‐Trimethylbenzene ND ND ND ND ND ND ND 1,2,4,5‐Tetramethylbenzene ND ND ND ND ND ND ND 1,2,4‐triethylbenzene ND ND ND ND ND ND ND 1,2,4‐Trimethylbenzene ND ND ND ND ND ND ND 1,2‐Dichloroethane ND ND ND ND ND ND ND 1,2‐Dichloroethylene (cis) ND ND ND ND ND ND ND 1,2‐Dichloroethylene (trans) ND ND ND ND ND ND ND 1,2‐Diethylbenzene ND ND ND ND ND ND ND 1,2‐dimethyl‐3‐ethylbenzene ND ND ND ND ND ND ND 1,2‐Dimethyl‐4‐Ethylbenzene ND ND ND ND ND ND ND 1,3,5‐triethylbenzene ND ND ND ND ND ND ND 1,3,5‐Trimethylbenzene ND ND ND ND ND ND ND 1,3‐Diethylbenzene ND ND ND ND ND ND ND 1,3‐Dimethyl‐2‐Ethylbenzene ND ND ND ND ND ND ND 1,3‐Dimethyl‐5‐Ethylbenzene ND ND ND ND ND ND ND 1,4‐dimethyl‐2‐ethylbenzene ND ND ND ND ND ND ND 1‐Decene ND ND ND ND ND ND ND 1‐ethyl‐1‐methylcyclopentane ND ND ND ND ND ND ND 1‐ethyl‐2,4‐dimethylbenzene ND ND ND ND ND ND ND 1‐Hexene ND ND ND ND ND ND ND 1‐Methyl‐2‐Ethylbenzene ND ND ND ND ND ND ND 1‐Methyl‐2‐n‐Propylbenzene ND ND ND ND ND ND ND 1‐Methyl‐3‐Ethylbenzene ND ND ND ND ND ND ND 1‐methyl‐3‐n‐propylbenzene ND ND ND ND ND ND ND 1‐Methyl‐4‐Ethylbenzene ND ND ND ND ND ND ND 1‐methyl‐4‐n‐propylbenzene/1,4‐Diethylbenz ND ND ND ND ND ND ND 1‐Nonene ND ND ND ND ND ND ND 1‐Octene ND ND ND ND ND ND ND 1‐Pentene ND ND ND ND ND ND ND 2,2,3‐trimethylbutane ND ND ND ND ND ND ND 2,2,4‐Trimethylhexane ND ND ND ND ND ND ND 2,2,4‐Trimethylpentane/1‐heptene ND ND ND ND ND ND ND 2,2‐Dimethylbutane ND ND ND ND ND ND ND 2,2‐Dimethylheptane ND ND ND ND ND ND ND 2,2‐dimethylhexane ND ND ND ND ND ND ND

Page 6 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK DOWNSTREAM Sample ID RC‐DN‐061016 RC‐DN‐061016‐FD RC‐DN‐061216‐AM RC‐DN‐061416‐AM RC‐DN‐061516‐AM RC‐DN‐061616‐AM RC‐DN‐062716‐AM Sample Date 6/10/16 12:05 6/10/16 12:00 6/12/16 9:00 6/14/16 8:38 6/15/16 11:30 6/16/16 10:10 6/27/16 10:00 1,1,1‐Trichloroethane ND ND ND ND ND ND ND 2,2‐Dimethyloctane ND ND ND ND ND ND ND 2,2‐Dimethylpentane ND ND ND ND ND ND ND 2,3,3‐Trimethylpentane ND ND ND ND ND ND ND 2,3,4‐Trimethylpentane ND ND ND ND ND ND ND 2,3‐Dimethylbutane ND ND ND ND ND ND ND 2,3‐Dimethylheptane ND ND ND ND ND ND ND 2,3‐Dimethylhexane ND ND ND ND ND ND ND 2,3‐Dimethyloctane ND ND ND ND ND ND ND 2,3‐Dimethylpentane ND ND ND ND ND ND ND 2,4‐Dimethylheptane ND ND ND ND ND ND ND 2,4‐Dimethylhexane ND ND ND ND ND ND ND 2,4‐Dimethylpentane ND ND ND ND ND ND ND 2,5‐dimethylheptane ND ND ND ND ND ND ND 2,5‐Dimethylhexane/2,2,3‐trimethylpentane ND ND ND ND ND ND ND 2,6‐Dimethylheptane ND ND ND ND ND ND ND 2‐Ethylthiophene ND ND ND ND ND ND ND 2‐methyl‐1,3‐butadiene ND ND ND ND ND ND ND 2‐Methyl‐1‐Butene ND ND ND ND ND ND ND 2‐Methyl‐1‐Hexene/trans‐1,2‐dimethylcyclop ND ND ND ND ND ND ND 2‐methylbutylbenzene ND ND ND ND ND ND ND 2‐Methylheptane ND ND ND ND ND ND ND 2‐Methylhexane ND ND ND ND ND ND ND 2‐methylnonane ND ND ND ND ND ND ND 2‐Methyloctane ND ND ND ND ND ND ND 2‐Methylpentane ND ND ND ND ND ND ND 2‐Methylpentene‐2 ND ND ND ND ND ND ND 2‐Methylthiophene ND ND ND ND ND ND ND 3,3‐Diethylpentane ND ND ND ND ND ND ND 3,3‐dimethylheptane/3,5‐dimethylheptane ND ND ND ND ND ND ND 3,3‐Dimethyloctane ND ND ND ND ND ND ND 3,3‐dimethylpentane ND ND ND ND ND ND ND 3,4‐Dimethylheptane (D) ND ND ND ND ND ND ND 3,4‐Dimethylheptane (L) ND ND ND ND ND ND ND 3‐ethylhexane ND ND ND ND ND ND ND 3‐ethyloctane ND ND ND ND ND ND ND 3‐ethylpentane ND ND ND ND ND ND ND 3‐methyl‐1‐butene ND ND ND ND ND ND ND 3‐Methylheptane ND ND ND ND ND ND ND 3‐Methylhexane ND ND ND ND ND ND ND 3‐Methylnonane ND ND ND ND ND ND ND 3‐Methyloctane ND ND ND ND ND ND ND

Page 7 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK DOWNSTREAM Sample ID RC‐DN‐061016 RC‐DN‐061016‐FD RC‐DN‐061216‐AM RC‐DN‐061416‐AM RC‐DN‐061516‐AM RC‐DN‐061616‐AM RC‐DN‐062716‐AM Sample Date 6/10/16 12:05 6/10/16 12:00 6/12/16 9:00 6/14/16 8:38 6/15/16 11:30 6/16/16 10:10 6/27/16 10:00 1,1,1‐Trichloroethane ND ND ND ND ND ND ND 3‐Methylpentane ND ND ND ND ND ND ND 3‐Methylthiophene ND ND ND ND ND ND ND 4‐Methylheptane ND ND ND ND ND ND ND 4‐Methyloctane ND ND ND ND ND ND ND 4‐methylpentene‐1 ND ND ND ND ND ND ND Benzene 0.28 J 0.3 J 0.05 J ND ND ND 0.05 J Benzo(b)thiophene ND ND ND ND ND ND ND butyl benzene ND ND ND ND ND ND ND ccc‐1,2,3‐trimethylcyclopentane ND ND ND ND ND ND ND ccc‐1,3,5‐trimethylcyclohexane ND ND ND ND ND ND ND cis‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND cis‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND cis‐2‐Heptene ND ND ND ND ND ND ND cis‐2‐Hexene ND ND ND ND ND ND ND cis‐2‐Nonene ND ND ND ND ND ND ND Cis‐2‐octene ND ND ND ND ND ND ND cis‐2‐Pentene ND ND ND ND ND ND ND cis‐3‐Heptene ND ND ND ND ND ND ND cis‐3‐Nonene ND ND ND ND ND ND ND ctc‐1,2,3‐Trimethylcyclopentane ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ctc‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclohexane ND ND ND ND ND ND ND ctt‐1,2,4‐Trimethylcyclopentane ND ND ND ND ND ND ND Cyclohexane ND 0.10 J ND ND ND ND ND Cyclopentane 0.10 J 0.14 J 0.06 J ND ND ND 0.02 J Di‐isopropyl ether ND ND ND ND ND ND ND ethanol ND ND ND ND ND ND ND Ethyl tert butyl ether ND ND ND ND ND ND ND Ethylbenzene 0.02 J 0.02 J 0.02 J ND ND ND ND Ethylcyclohexane/n‐propylcyclopentane ND ND ND ND ND ND ND ethylcyclopentane ND ND ND ND ND ND ND Indane ND ND ND ND ND ND ND isobutylbenzene ND ND ND ND ND ND ND isobutylcyclohexane ND ND ND ND ND ND ND isobutylcyclopentane ND ND ND ND ND ND ND Isopentane ND ND ND ND ND ND ND Isopropylbenzene ND ND ND ND ND ND ND Isopropylcyclohexane ND ND ND ND ND ND ND Isopropylcyclopentane ND ND ND ND ND ND ND m‐cymene ND ND ND ND ND ND ND

Page 8 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK DOWNSTREAM Sample ID RC‐DN‐061016 RC‐DN‐061016‐FD RC‐DN‐061216‐AM RC‐DN‐061416‐AM RC‐DN‐061516‐AM RC‐DN‐061616‐AM RC‐DN‐062716‐AM Sample Date 6/10/16 12:05 6/10/16 12:00 6/12/16 9:00 6/14/16 8:38 6/15/16 11:30 6/16/16 10:10 6/27/16 10:00 1,1,1‐Trichloroethane ND ND ND ND ND ND ND Methyl tert butyl ether ND ND ND ND ND ND ND Methylcyclohexane ND ND ND ND ND ND ND Methylcyclopentane 0.07 J 0.12 J 0.04 J ND ND ND ND MMT ND ND ND ND ND ND ND m‐Xylene 0.03 J 0.04 J 0.02 J ND ND ND ND Naphthalene ND ND ND ND ND ND ND n‐Butylcyclopentane ND ND ND ND ND ND ND n‐Decane ND ND ND ND ND ND ND n‐Dodecane ND ND 0.06 J ND ND ND ND n‐Heptane ND ND ND ND ND ND ND n‐Hexane ND ND ND ND ND ND ND n‐hexylbenzene ND ND ND ND ND ND ND n‐Nonane ND ND ND ND ND ND ND n‐Octane ND ND ND ND ND ND ND n‐Pentane 0.21 J 0.24 J 0.12 J ND ND ND 0.05 J n‐Pentylbenzene ND ND ND ND ND ND ND n‐Undecane ND ND ND ND ND ND ND o‐cymene ND ND ND ND ND ND ND o‐Xylene 0.02 J 0.02 J ND ND ND ND 0.04 J p‐Cymene ND ND ND ND ND ND ND Propylbenzene ND ND ND ND ND ND ND p‐Xylene ND 0.01 J 0.01 J ND ND ND ND sec‐Butylbenzene ND ND ND ND ND ND ND Styrene ND ND ND ND ND ND ND t‐Butanol ND ND ND ND ND ND ND Tert amyl methyl ether ND ND ND ND ND ND ND tert‐1‐butyl‐2‐methylbenzene ND ND ND ND ND ND ND tert‐1‐butyl‐3,5‐dimethylbenzene ND ND ND ND ND ND ND tert‐1‐butyl‐4‐ethylbenzene ND ND ND ND ND ND ND tert‐1‐methyl‐2‐(4MP)cyclopentane ND ND ND ND ND ND ND tert‐1‐methyl‐2‐propylcyclohexane ND ND ND ND ND ND ND tert‐butylbenzene ND ND ND ND ND ND ND Tetrachloroethylene ND ND ND ND ND ND ND Thiophene ND ND ND ND ND ND ND Toluene 0.12 J 0.12 J 0.08 J ND ND 0.02 J 0.08 J trans‐1,2‐dimethylcyclohexane ND ND ND ND ND ND ND trans‐1,3‐dimethylcyclopentane ND ND ND ND ND ND ND trans‐1,4‐dimethylcyclohexane ND ND ND ND ND ND ND trans‐2‐Heptene ND ND ND ND ND ND ND trans‐2‐Hexene ND ND ND ND ND ND ND trans‐2‐Nonene ND ND ND ND ND ND ND

Page 9 of 10 Table D‐4. Rock Creek Surface Water Sample Results ‐ PIANO analysis Union Pacific Railroad Company Mosier Release Site Assessment Report ROCK CREEK DOWNSTREAM Sample ID RC‐DN‐061016 RC‐DN‐061016‐FD RC‐DN‐061216‐AM RC‐DN‐061416‐AM RC‐DN‐061516‐AM RC‐DN‐061616‐AM RC‐DN‐062716‐AM Sample Date 6/10/16 12:05 6/10/16 12:00 6/12/16 9:00 6/14/16 8:38 6/15/16 11:30 6/16/16 10:10 6/27/16 10:00 1,1,1‐Trichloroethane ND ND ND ND ND ND ND trans‐2‐Octene ND ND ND ND ND ND ND trans‐2‐Pentene ND ND ND ND ND ND ND trans‐3‐Heptene ND ND ND ND ND ND ND trans‐3‐Nonene ND ND ND ND ND ND ND Trichloroethylene ND ND ND ND ND ND ND Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit ND = Analyte was not detected above the MDL Qualifiers J ‐ Result is less than the reporting limit but greater than or equal to the method detection limit and the concentration is an approximate value.

Page 10 of 10

OSU Mosier Data vs Columbia River - All data

OVERERALL DATA - Columbia River Upstream/East(2) Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Compound CAS (1) East 1(3) East 2(3) FCV (µg/L) 060516 060616 060616-PM 060716-AM 060716-PM 060816-AM 060816-PM 060916-AM 060916-PM 061016-AM 061116-AM

Volatile Organic Compounds (µg/L)

Naphthalene 91-20-3 193.5 0.00268 0.00304 0.26 J 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 0.000164 0.00019 0.003 U 0.01 J 0.006 U 0.006 U 0.0062 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.006 U 0.0073 U 2-Methylnaphthalene 91-57-6 72.16 0.000191 0.000211 0.0061 U 0.023 J 0.009 U 0.009 U 0.0093 U 0.009 U 0.0092 U 0.009 U 0.009 U 0.009 U 0.011 U Acenaphthene 83-32-9 55.85 0.000506 0.000486 0.0061 U 0.0025 J 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U Acenaphthylene 208-96-8 306.9 0.0000324 J 0.000048 J 0.0061 U 0.0024 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U Anthracene 120-12-7 20.73 0.0000442 0.0000436 0.0041 U 0.0038 J 0.0044 J 0.003 U 0.0031 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U Benz[a]anthracene 56-55-3 2.227 0.0000176 0.000017 0.0041 U 0.0031 J 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U Benzo[a]pyrene 50-32-8 0.9573 0.0000035 J 0.00000256 J 0.003 U 0.0036 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U Benzo[b]fluoranthene 205-99-2 0.6774 0.0000172 0.0000164 0.003 U 0.0097 U 0.008 U 0.008 U 0.0083 U 0.008 U 0.0082 U 0.008 U 0.008 U 0.008 U 0.0098 U Benzo[ghi]perylene 191-24-2 0.4391 0.00000494 0.00000392 0.0026 J B 0.0036 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U Benzo[k]fluoranthene 207-08-9 0.6415 0.0000056 0.00000612 0.0061 U 0.011 U 0.009 U 0.009 U 0.0093 U 0.009 U 0.0092 U 0.009 U 0.009 U 0.009 U 0.011 U Chrysene 218-01-9 2.042 0.0000401 0.000043 0.0061 U 0.0073 U 0.006 U 0.006 U 0.0062 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.006 U 0.0073 U Dibenz[a,h]anthracene 53-70-3 0.2825 0.00000108 U 0.0000013 U 0.003 U 0.0024 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0024 U Fluoranthene 206-44-0 7.109 0.00055 0.00062 0.008 J 0.0068 J 0.0066 J 0.0042 J 0.0026 J 0.002 U 0.0021 U 0.0021 J B 0.002 U 0.002 U 0.0024 J Fluorene 86-73-7 39.3 0.000349 0.000388 0.0061 U 0.0041 J 0.0046 J 0.0036 J 0.0039 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0037 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 2.67E-07 U 3.23E-07 U 0.0041 U 0.0085 U 0.007 U 0.007 U 0.0072 U 0.007 U 0.0072 U 0.007 U 0.007 U 0.007 U 0.0085 U Naphthalene 91-20-3 193.5 0.00268 0.00304 0.0061 U 0.019 J 0.018 J 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.016 U Phenanthrene 85-01-8 19.13 0.00107 0.00114 0.0097 J 0.011 J 0.011 J 0.012 J 0.0069 J 0.0055 J B 0.0061 J B 0.0052 J 0.0056 J 0.004 U 0.0049 J Pyrene 129-00-0 10.11 0.000282 0.000288 0.0063 J 0.0062 J 0.0045 J 0.0058 J 0.0041 U 0.004 U 0.0041 U 0.004 U 0.004 U 0.004 U 0.0049 U

Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Upstream- Compound CAS FCV (µg/L)(1) 061216-AM 061316-AM 061416-AM 061516-AM 061616-AM 061716-AM 062016-AM 062216-AM 062716-AM 070716 071316 072216 080516 081516 Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 0.0061 U 0.006 U 0.006 U 0.006 U 0.007 J 0.006 U 0.0062 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.0063 U 0.0061 U 0.006 U 2-Methylnaphthalene 91-57-6 72.16 0.0092 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.0092 U 0.0091 U 0.009 U 0.0091 U 0.009 U 0.0094 U 0.0092 U 0.009 U Acenaphthene 83-32-9 55.85 0.002 U 0.002 U 0.002 U 0.002 U 0.0053 J 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0061 J B 0.0021 U 0.002 U 0.002 U Acenaphthylene 208-96-8 306.9 0.002 U 0.002 U 0.002 U 0.002 U 0.0053 J 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0061 J B 0.0021 U 0.002 U 0.002 U Anthracene 120-12-7 20.73 0.0031 U 0.003 U 0.003 U 0.003 U 0.0061 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0057 J B 0.0031 U 0.0031 U 0.003 U Benz[a]anthracene 56-55-3 2.227 0.002 U 0.002 U 0.002 U 0.002 U 0.0068 J 0.002 U 0.0021 U 0.011 J 0.002 U 0.002 U 0.0056 J B 0.0021 U 0.002 U 0.0046 J Benzo[a]pyrene 50-32-8 0.9573 0.0031 U 0.003 U 0.003 U 0.003 U 0.0058 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0045 J B 0.0031 U 0.0031 U 0.003 U Benzo[b]fluoranthene 205-99-2 0.6774 0.0081 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.0082 U 0.0081 U 0.008 U 0.0081 U 0.008 U 0.0084 U 0.0082 U 0.008 U Benzo[ghi]perylene 191-24-2 0.4391 0.0031 U 0.003 U 0.003 U 0.003 U 0.0058 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0047 J B 0.0031 U 0.0031 U 0.003 U Benzo[k]fluoranthene 207-08-9 0.6415 0.0092 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.0092 U 0.0091 U 0.009 U 0.0091 U 0.009 U 0.0094 U 0.0092 U 0.009 U Chrysene 218-01-9 2.042 0.0061 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0062 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.0063 U 0.0061 U 0.006 U Dibenz[a,h]anthracene 53-70-3 0.2825 0.002 U 0.002 U 0.002 U 0.002 U 0.0046 J 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0072 J B 0.0021 U 0.002 U 0.002 U Fluoranthene 206-44-0 7.109 0.002 U 0.002 U 0.002 U 0.002 U 0.0097 J 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.0065 J B 0.0021 U 0.002 U 0.0043 J Fluorene 86-73-7 39.3 0.0031 U 0.003 U 0.003 U 0.003 U 0.0057 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0063 J B 0.0031 U 0.0031 U 0.003 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 0.0071 U 0.007 U 0.007 U 0.007 U 0.0073 J 0.007 U 0.0072 U 0.0071 U 0.007 U 0.0071 U 0.007 U 0.0073 U 0.0072 U 0.007 U Naphthalene 91-20-3 193.5 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.015 J 0.013 U 0.013 U Phenanthrene 85-01-8 19.13 0.0044 J 0.005 J B 0.0066 J 0.004 U 0.0093 J 0.0056 J 0.0041 U 0.0063 J B 0.011 J 0.0052 J 0.0088 J B 0.0055 J 0.005 J 0.0041 J Pyrene 129-00-0 10.11 0.0041 U 0.004 U 0.004 U 0.004 U 0.01 J 0.004 U 0.0041 U 0.0041 U 0.004 U 0.0041 U 0.0086 J B 0.0042 U 0.0041 U 0.0064 J

Notes: Qualifiers: Results shown in bold denote detected concentrations. * LCS or LCSD is outside acceptance limits. (1) FCVs taken from EPA's Procedures for the Derivation of ESBs for the Protection of Benthic Organisms: PAH Mixtures (2003) B - Compound was found in both the method blank and sample. (2) Unless otherwise indicated, grab samples taken from top six inches of water F1 - MS and/or MSD Recovery is outside acceptance limits. (3) LDPE water samplers deployed approximately 2 feet above mudline J - Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value. "-" - Not analyzed. U - Analyte was not detected above the method detection limit (MDL). ng/L = ppt OSU Mosier Data vs Columbia River - All data

Columbia River Downstream/West

Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Compound CAS (1) West 1(3) West 2(3) FCV (µg/L) 060516 060616 060616-PM 060716-AM 060716-PM 060816-AM 060816-PM 060916-AM 060916-PM 061016-AM 061116-AM

Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 0.00361 0.00457 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 0.000282 0.0003 0.0032 U 0.0062 U 0.012 J 0.0083 J 0.0065 J 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 2-Methylnaphthalene 91-57-6 72.16 0.000285 0.000299 0.0064 U 0.01 J 0.025 J 0.014 J 0.011 J 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U Acenaphthene 83-32-9 55.85 0.000397 0.000441 0.0064 U 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 208-96-8 306.9 0.0000376 J 0.0000375 J 0.0064 U 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 120-12-7 20.73 0.0000316 0.0000425 0.0043 U 0.0031 U 0.003 U 0.0031 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benz[a]anthracene 56-55-3 2.227 0.00000691 0.0000106 0.0043 U 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 50-32-8 0.9573 0.00000162 J 0.0000022 J 0.0032 U 0.0031 U 0.003 U 0.0031 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 205-99-2 0.6774 0.00000627 0.00001 0.0032 U 0.0083 U 0.008 U 0.0084 U 0.0086 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U Benzo[ghi]perylene 191-24-2 0.4391 0.000002 0.00000362 0.0021 U 0.0031 U 0.003 U 0.0031 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 207-08-9 0.6415 0.00000226 0.00000374 0.0064 U 0.0093 U 0.009 U 0.0094 U 0.0096 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U Chrysene 218-01-9 2.042 0.0000145 0.000023 0.0064 U 0.0062 U 0.006 U 0.0063 U 0.0064 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U Dibenz[a,h]anthracene 53-70-3 0.2825 0.00000106 U 0.00000175 U 0.0032 U 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 206-44-0 7.109 0.000342 0.000496 0.0043 U 0.0021 U 0.003 J 0.0029 J 0.0031 J 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluorene 86-73-7 39.3 0.000286 0.00035 0.0064 U 0.0031 U 0.003 U 0.0031 U 0.0032 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 2.62E-07 U 4.34E-07 U 0.0043 U 0.0072 U 0.007 U 0.0073 U 0.0075 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U Naphthalene 91-20-3 193.5 0.00361 0.00457 0.0064 U 0.013 U 0.035 J 0.014 U 0.016 J 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 85-01-8 19.13 0.000791 0.00104 0.0064 U 0.0041 U 0.0077 J 0.0067 J 0.0097 J 0.0063 J B 0.0056 J B 0.004 U 0.0045 J 0.004 U 0.0045 J Pyrene 129-00-0 10.11 0.00014 0.000185 0.0043 U 0.0041 U 0.004 U 0.0042 U 0.0043 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U 0.004 U

Columbia River Downstream/West

Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Downstream- Compound CAS (1) FCV (µg/L) 061216-AM 061316-AM 061416-AM 061516-AM 061616-AM 061716-AM 062016-AM 062216-AM 062716-AM 070716 071316 072216 080516 081516

Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1 J 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.0064 U 0.006 U 0.006 U 0.006 U 2-Methylnaphthalene 91-57-6 72.16 0.009 U 0.0091 U 0.0089 U 0.009 U 0.009 U 0.009 U 0.009 U 0.0093 U 0.009 U 0.009 U 0.0096 U 0.009 U 0.009 U 0.0091 U Acenaphthene 83-32-9 55.85 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 J B 0.002 U 0.002 U 0.002 U Acenaphthylene 208-96-8 306.9 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0063 U 0.002 U 0.002 U 0.002 U Anthracene 120-12-7 20.73 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.014 J 0.003 U 0.0031 U 0.003 U 0.003 U 0.0042 U 0.003 U 0.003 U 0.003 U Benz[a]anthracene 56-55-3 2.227 0.002 U 0.002 U 0.002 U 0.002 U 0.0022 J 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0042 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 50-32-8 0.9573 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.0063 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 205-99-2 0.6774 0.008 U 0.008 U 0.0079 U 0.008 U 0.008 U 0.008 U 0.008 U 0.0083 U 0.008 U 0.008 U 0.0063 U 0.008 U 0.008 U 0.0081 U Benzo[ghi]perylene 191-24-2 0.4391 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.0047 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 207-08-9 0.6415 0.009 U 0.0091 U 0.0089 U 0.009 U 0.009 U 0.01 J 0.009 U 0.0093 U 0.009 U 0.009 U 0.0063 U 0.009 U 0.009 U 0.0091 U Chrysene 218-01-9 2.042 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0062 U 0.006 U 0.006 U 0.0063 U 0.006 U 0.006 U 0.006 U Dibenz[a,h]anthracene 53-70-3 0.2825 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0054 U 0.002 U 0.002 U 0.002 U Fluoranthene 206-44-0 7.109 0.002 U 0.002 U 0.0062 J 0.002 U 0.0052 J 0.002 U 0.002 U 0.0027 J 0.002 U 0.002 U 0.0024 J B 0.002 U 0.002 U 0.002 U Fluorene 86-73-7 39.3 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 0.007 U 0.007 U 0.0069 U 0.007 U 0.007 U 0.007 U 0.007 U 0.0072 U 0.007 U 0.007 U 0.0075 U 0.007 U 0.007 U 0.0071 U Naphthalene 91-20-3 193.5 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.014 U 0.013 U 0.013 U 0.013 U Phenanthrene 85-01-8 19.13 0.0052 J 0.004 U 0.0069 J 0.004 U 0.0051 J 0.0055 J 0.004 U 0.0041 U 0.005 J 0.005 J 0.0043 U 0.004 U 0.0041 J 0.004 U Pyrene 129-00-0 10.11 0.004 U 0.004 U 0.0049 J 0.004 U 0.005 J 0.004 U 0.004 U 0.0041 U 0.004 U 0.004 U 0.0043 U 0.004 U 0.004 U 0.004 U

Notes: Qualifiers: Results shown in bold denote detected concentrations. * LCS or LCSD is outside acceptance limits. (1) FCVs taken from EPA's Procedures for the Derivation of ESBs for the Protection of Benthic Organisms: PAH Mixtures (2003) B - Compound was found in both the method blank and sample. (2) Unless otherwise indicated, grab samples taken from top six inches of water F1 - MS and/or MSD Recovery is outside acceptance limits. (3) LDPE water samplers deployed approximately 2 feet above mudline J - Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value. "-" - Not analyzed. U - Analyte was not detected above the method detection limit (MDL). ng/L = ppt NSV = no screening value OSU Mosier Data vs Columbia River - All data

Columbia River Downstream/West Source-060616- Source-060716- Source-060716- Source-060816- Source-060816- Source-060916- Source-060916- Source-061016- Source-061116- Compound CAS (1) Center 2 (1)(3) Center 2 (2)(3) Center 2 (3)(3) Source-060516 Source-060616 FCV (µg/L) PM AM PM AM PM AM PM AM AM Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 0.00328 0.00377 0.00351 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 0.000339 0.000323 0.000428 0.0048 J 0.013 J 0.01 J 0.0061 J 0.0097 J 0.0067 U 0.006 U 0.006 U 0.006 U 0.0084 J 0.006 U 2-Methylnaphthalene 91-57-6 72.16 0.000378 0.000373 0.000514 0.0063 U 0.021 J 0.017 J 0.013 J 0.014 J 0.01 U 0.009 U 0.009 U 0.009 U 0.0091 J 0.009 U Acenaphthene 83-32-9 55.85 0.000399 0.000434 0.000429 0.0063 U 0.002 U 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 208-96-8 306.9 0.0000414 J 0.0000406 J 0.0000369 J 0.0063 U 0.002 U 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 120-12-7 20.73 0.0000314 0.0000391 0.0000324 0.0042 U 0.003 U 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benz[a]anthracene 56-55-3 2.227 0.00000814 0.0000104 0.00000874 0.0042 U 0.002 U 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 J 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 50-32-8 0.9573 0.00000141 J 0.0000016 J 0.00000143 J 0.0063 U 0.003 U 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 205-99-2 0.6774 0.00000706 0.00000911 0.00000724 0.0063 U 0.008 U 0.0093 U 0.008 U 0.008 U 0.009 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U Benzo[ghi]perylene 191-24-2 0.4391 0.00000238 0.00000261 0.00000204 0.0047 J B 0.003 U 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 207-08-9 0.6415 0.00000257 0.00000322 0.00000264 0.0063 U 0.009 U 0.01 U 0.009 U 0.009 U 0.01 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U Chrysene 218-01-9 2.042 0.0000166 0.0000217 0.000018 0.0063 U 0.006 U 0.007 U 0.006 U 0.006 U 0.0067 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U Dibenz[a,h]anthracene 53-70-3 0.2825 8.96E-07 U 0.00000113 U 9.22E-07 U 0.0054 J B 0.002 U 0.0023 U 0.002 U 0.002 U 0.0022 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 206-44-0 7.109 0.000365 0.000452 0.000396 0.0042 U 0.002 U 0.0025 J 0.0025 J 0.002 U 0.0044 J B 0.0055 J B 0.002 U 0.002 U 0.002 U 0.002 U Fluorene 86-73-7 39.3 0.000282 0.000309 0.000299 0.0063 U 0.003 U 0.0035 U 0.003 U 0.003 U 0.0034 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 2.22E-07 U 2.81E-07 U 2.29E-07 U 0.0043 J 0.007 U 0.0081 U 0.007 U 0.007 U 0.0079 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U Naphthalene 91-20-3 193.5 0.00328 0.00377 0.00351 0.0063 U 0.013 U 0.025 J 0.013 U 0.013 U 0.015 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 85-01-8 19.13 0.000778 0.000843 0.000821 0.0063 U 0.004 U 0.006 J 0.0081 J 0.004 U 0.0072 J B 0.0074 J B 0.004 U 0.006 J 0.0048 J B 0.0048 J Pyrene 129-00-0 10.11 0.000158 0.000188 0.000173 0.0042 U 0.004 U 0.0046 U 0.004 U 0.004 U 0.0052 J B 0.0058 J B 0.004 U 0.004 U 0.004 U 0.004 U

Columbia River Downstream/West

Source-061216- Source-061316- Source-061416- Source-061516- Source-061616- Source-061716- Source-062016- Source-062216- Source-062716- Source- Source- Source- Source- Compound CAS FCV (µg/L)(1) Source-081516 AM AM AM AM AM AM AM AM AM 070716 071316 072216 080516

Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 0.006 U 0.013 J 0.006 U 0.006 U 0.006 U 0.25 0.017 J 0.012 J 0.006 U 0.006 U 0.006 U 0.0061 U 0.0061 U 0.0061 U 2-Methylnaphthalene 91-57-6 72.16 0.009 U 0.017 J B 0.009 U 0.009 U 0.009 U 0.27 0.02 J 0.021 J 0.0091 U 0.009 U 0.009 U 0.0092 U 0.0092 U 0.0091 U Acenaphthene 83-32-9 55.85 0.002 U 0.0031 J 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 J B 0.002 U 0.002 U 0.002 U Acenaphthylene 208-96-8 306.9 0.002 U 0.0022 J 0.002 U 0.002 U 0.002 U 0.01 J 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 120-12-7 20.73 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.0042 J B 0.0031 U 0.0031 U 0.003 U Benz[a]anthracene 56-55-3 2.227 0.002 U 0.002 U 0.002 U 0.002 U 0.0022 J 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0043 J 0.002 U Benzo[a]pyrene 50-32-8 0.9573 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.003 U Benzo[b]fluoranthene 205-99-2 0.6774 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.008 U 0.0081 U 0.0082 U 0.008 U 0.008 U 0.008 U 0.0082 U 0.0081 U 0.0081 U Benzo[ghi]perylene 191-24-2 0.4391 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.003 U Benzo[k]fluoranthene 207-08-9 0.6415 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.009 U 0.0091 U 0.0093 U 0.0091 U 0.009 U 0.009 U 0.0092 U 0.0092 U 0.0091 U Chrysene 218-01-9 2.042 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0061 U 0.0062 U 0.006 U 0.006 U 0.006 U 0.0061 U 0.0061 U 0.0061 U Dibenz[a,h]anthracene 53-70-3 0.2825 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 206-44-0 7.109 0.002 U 0.0028 J B 0.002 U 0.002 U 0.005 J 0.002 U 0.002 U 0.0028 J 0.002 U 0.002 U 0.0034 J B 0.002 U 0.002 U 0.002 U Fluorene 86-73-7 39.3 0.003 U 0.0062 J 0.003 U 0.003 U 0.003 U 0.02 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.003 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.007 U 0.0071 U 0.0072 U 0.007 U 0.007 U 0.007 U 0.0072 U 0.0071 U 0.0071 U Naphthalene 91-20-3 193.5 0.013 U 0.013 J 0.013 U 0.013 U 0.013 U 0.097 0.016 J 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 85-01-8 19.13 0.0043 J 0.0069 J B 0.0071 J 0.004 J 0.0051 J 0.044 0.0066 J 0.0061 J B 0.0068 J 0.0058 J 0.0073 J B 0.0042 J 0.0041 U 0.004 U Pyrene 129-00-0 10.11 0.004 U 0.004 U 0.004 U 0.004 U 0.0049 J 0.004 U 0.004 U 0.0041 U 0.004 U 0.004 U 0.0053 J B 0.0041 U 0.0041 U 0.004 U

Notes: Qualifiers: Results shown in bold denote detected concentrations. * LCS or LCSD is outside acceptance limits. (1) FCVs taken from EPA's Procedures for the Derivation of ESBs for the Protection of Benthic Organisms: PAH Mixtures (2003) B - Compound was found in both the method blank and sample. (2) Unless otherwise indicated, grab samples taken from top six inches of water F1 - MS and/or MSD Recovery is outside acceptance limits. (3) LDPE water samplers deployed approximately 2 feet above mudline J - Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value. "-" - Not analyzed. U - Analyte was not detected above the method detection limit (MDL). ng/L = ppt NSV = no screening value Rock Creek Surface Water Sample Results - Semi-Volatile Organic Compounds

Compound CAS FCV (µg/L) ROCK CREEK UPSTREAM Semi-Volatile Organic Compounds (µg/L) RC-UP-061016 RC-UP-061216-AM RC-UP-061416-AM RC-UP-061516-AM RC-UP-061616-AM RC-UP-062716-AM RC-UP-070716 RC-UP-080516 1-Methylnaphthalene 90-12-0 75.37 0.0076 J 0.006 U 0.0079 J 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 2-Methylnaphthalene 91-57-6 72.16 0.0097 J 0.0091 U 0.0091 U 0.009 U 0.009 U 0.0091 U 0.009 U 0.009 U Acenaphthene 83-32-9 55.85 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 208-96-8 306.9 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 120-12-7 20.73 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benz[a]anthracene 56-55-3 2.227 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 J 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 50-32-8 0.9573 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 205-99-2 0.6774 0.008 U 0.0081 U 0.0081 U 0.008 U 0.008 U 0.0081 U 0.008 U 0.008 U Benzo[ghi]perylene 191-24-2 0.4391 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 207-08-9 0.6415 0.009 U 0.0091 U 0.0091 U 0.009 U 0.009 U 0.0091 U 0.009 U 0.009 U Chrysene 218-01-9 2.042 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U 0.006 U Dibenz[a,h]anthracene 53-70-3 0.2825 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 206-44-0 7.109 0.002 U 0.002 U 0.002 U 0.002 U 0.0058 J 0.002 U 0.002 U 0.002 U Fluorene 86-73-7 39.3 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 0.007 U 0.007 U 0.0071 U 0.007 U 0.007 U 0.0071 U 0.007 U 0.007 U Naphthalene 91-20-3 193.5 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U Phenanthrene 85-01-8 19.13 0.006 J B 0.0042 J 0.011 J 0.0059 J 0.0058 J 0.0071 J 0.007 J 0.0056 J Pyrene 129-00-0 10.11 0.004 U 0.004 U 0.004 U 0.004 U 0.0052 J 0.004 U 0.004 U 0.004 U

Compound CAS FCV (µg/L) ROCK CREEK DOWNSTREAM RC-DN-061016 RC-DN-061016-FD RC-DN-061216-AM RC-DN-061416-AM RC-DN-061516-AM RC-DN-061616-AM RC-DN-062716-AM RC-DN-070716 RC-DN-080516 Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 0.0061 U 0.0061 U 0.006 U 0.006 U 0.0061 U 0.006 U 0.0061 U 0.006 U 0.006 U 2-Methylnaphthalene 91-57-6 72.16 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.009 U 0.0091 U 0.0091 U 0.009 U Acenaphthene 83-32-9 55.85 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Acenaphthylene 208-96-8 306.9 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Anthracene 120-12-7 20.73 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0052 J 0.003 U 0.003 U Benz[a]anthracene 56-55-3 2.227 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0034 J 0.022 0.002 U 0.002 U Benzo[a]pyrene 50-32-8 0.9573 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.014 J 0.003 U 0.003 U Benzo[b]fluoranthene 205-99-2 0.6774 0.0081 U 0.0081 U 0.0081 U 0.0081 U 0.0081 U 0.008 U 0.024 0.0081 U 0.008 U Benzo[ghi]perylene 191-24-2 0.4391 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.029 0.003 U 0.003 U Benzo[k]fluoranthene 207-08-9 0.6415 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.0091 U 0.009 U 0.024 J 0.0091 U 0.009 U Chrysene 218-01-9 2.042 0.0061 U 0.0061 U 0.006 U 0.006 U 0.0061 U 0.006 U 0.027 0.006 U 0.006 U Dibenz[a,h]anthracene 53-70-3 0.2825 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.03 0.002 U 0.002 U Fluoranthene 206-44-0 7.109 0.002 U 0.0031 J B 0.002 U 0.002 U 0.002 U 0.005 J 0.013 J 0.002 U 0.002 U Fluorene 86-73-7 39.3 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Indeno[1,2,3-cd]pyrene 193-39-5 0.275 0.0071 U 0.0071 U 0.0071 U 0.0071 U 0.0071 U 0.007 U 0.018 J 0.007 U 0.007 U Naphthalene 91-20-3 193.5 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.04 0.013 U 0.013 U Phenanthrene 85-01-8 19.13 0.0051 J B 0.0068 J B 0.0055 J 0.0083 J 0.0048 J 0.0066 J 0.01 J 0.0069 J 0.004 J Pyrene 129-00-0 10.11 0.0041 U 0.004 U 0.004 U 0.004 U 0.0041 U 0.0041 J 0.013 J 0.004 U 0.004 U Rock Creek Surface Water Sample Results - Volatile Organic Compounds - Downstream

Compound CAS FCV (µg/L) ROCK CREEK DOWNSTREAM RC-DN-061016 RC-DN-061016-FD RC-DN-061216-AM RC-DN-061416-AM RC-DN-061516-AM RC-DN-061616-AM RC-DN-062716-AM RC-DN-070716 RC-DN-080516 Volatile Organic Compounds (µg/L) 1,1,1,2-Tetrachloroethane #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1-Trichloroethane #N/A #N/A 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2-Tetrachloroethane #N/A #N/A 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2-Trichloroethane #N/A #N/A 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1-Dichloroethane #N/A #N/A 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1-Dichloroethene #N/A #N/A 0.33 U 0.33 U 0.33 U 0.33 * 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1-Dichloropropene #N/A #N/A 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3-Trichlorobenzene #N/A #N/A 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3-Trichloropropane #N/A #N/A 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3-Trimethylbenzene #N/A #N/A 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4-Trichlorobenzene #N/A #N/A 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4-Trimethylbenzene #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2-Dibromo-3-Chloropropane #N/A #N/A 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2-Dibromoethane #N/A #N/A 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2-Dichlorobenzene #N/A #N/A 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2-Dichloroethane #N/A #N/A 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2-Dichloropropane #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5-Trimethylbenzene #N/A #N/A 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 1,3-Dichlorobenzene #N/A #N/A 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3-Dichloropropane #N/A #N/A 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4-Dichlorobenzene #N/A #N/A 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2-Dichloropropane #N/A #N/A 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2-Chlorotoluene #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 * 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4-Chlorotoluene #N/A #N/A 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4-Isopropyltoluene #N/A #N/A 0.26 U 0.26 U 0.26 U 0.26 * 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene #N/A #N/A 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane #N/A #N/A 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 * 0.29 U 0.29 U* Bromodichloromethane #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform #N/A #N/A 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride #N/A #N/A 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene #N/A #N/A 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane #N/A #N/A 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform #N/A #N/A 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane #N/A #N/A 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis-1,2-Dichloroethene #N/A #N/A 0.21 * 0.21 * 0.21 U 0.21 U 0.21 U 0.21 U 0.21 * 0.21 U 0.21 U* cis-1,3-Dichloropropene #N/A #N/A 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane #N/A #N/A 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane #N/A #N/A 0.34 * 0.34 * 0.34 U 0.34 U 0.34 U 0.34 * 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane #N/A #N/A 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene #N/A #N/A 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene #N/A #N/A 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 * 0.49 U 0.49 U 0.49 U Isopropylbenzene #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Methyl tert-butyl ether #N/A #N/A 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride #N/A #N/A 1.3 * 1.3 * 1.3 U 1.3 U 1.3 U 1.3 U 1.3 * 1.3 U 1.3 U* m-Xylene & p-Xylene #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 0.3 U 0.3 U Naphthalene 91-20-3 193.5 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 0.26 U 0.26 U n-Butylbenzene #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 0.3 U 0.3 U N-Propylbenzene #N/A #N/A 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 0.13 U 0.13 U o-Xylene #N/A #N/A 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 0.49 U 0.49 U sec-Butylbenzene #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 0.27 U 0.3 J B Styrene #N/A #N/A 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 0.36 U 0.36 U t-Butylbenzene #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 0.27 U 0.27 U Tetrachloroethene #N/A #N/A 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 0.33 U 0.33 U Toluene #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 0.18 U 0.18 U trans-1,2-Dichloroethene #N/A #N/A 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 0.71 U 0.71 U* trans-1,3-Dichloropropene #N/A #N/A 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 0.16 U 0.16 U Trichloroethene #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 0.18 U 0.18 U* Trichlorofluoromethane #N/A #N/A 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 0.63 U 0.63 U Vinyl chloride #N/A #N/A 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 * 0.22 0.22 U 0.22 U Rock Creek Surface Water Sample Results - Volatile Organic Compounds - Upstream

Compound CAS FCV (µg/L) ROCK CREEK UPSTREAM RC-UP-061016 RC-UP-061216-AM RC-UP-061416-AM RC-UP-061516-AM RC-UP-061616-AM RC-UP-062716-AM RC-UP-070716 RC-UP-080516 Volatile Organic Compounds (µg/L) 1,1,1,2-Tetrachloroethane #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1-Trichloroethane #N/A #N/A 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2-Tetrachloroethane #N/A #N/A 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2-Trichloroethane #N/A #N/A 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1-Dichloroethane #N/A #N/A 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1-Dichloroethene #N/A #N/A 0.33 U 0.33 U 0.33 * 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1-Dichloropropene #N/A #N/A 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3-Trichlorobenzene #N/A #N/A 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3-Trichloropropane #N/A #N/A 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3-Trimethylbenzene #N/A #N/A 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 0.25 U 1,2,4-Trichlorobenzene #N/A #N/A 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4-Trimethylbenzene #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 1,2-Dibromo-3-Chloropropane #N/A #N/A 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2-Dibromoethane #N/A #N/A 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2-Dichlorobenzene #N/A #N/A 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2-Dichloroethane #N/A #N/A 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2-Dichloropropane #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5-Trimethylbenzene #N/A #N/A 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.35 J B 1,3-Dichlorobenzene #N/A #N/A 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3-Dichloropropane #N/A #N/A 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4-Dichlorobenzene #N/A #N/A 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2-Dichloropropane #N/A #N/A 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2-Chlorotoluene #N/A #N/A 0.3 U 0.3 U 0.3 * 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4-Chlorotoluene #N/A #N/A 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4-Isopropyltoluene #N/A #N/A 0.26 U 0.26 U 0.26 * 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U Benzene #N/A #N/A 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U 0.42 U Bromobenzene #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane #N/A #N/A 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 * 0.29 U 0.29 U* Bromodichloromethane #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform #N/A #N/A 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride #N/A #N/A 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene #N/A #N/A 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane #N/A #N/A 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform #N/A #N/A 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane #N/A #N/A 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis-1,2-Dichloroethene #N/A #N/A 0.21 * 0.21 U 0.21 U 0.21 U 0.21 U 0.21 * 0.21 U 0.21 U* cis-1,3-Dichloropropene #N/A #N/A 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane #N/A #N/A 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane #N/A #N/A 0.34 * 0.34 U 0.34 U 0.34 U 0.34 * 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane #N/A #N/A 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene #N/A #N/A 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Hexachlorobutadiene #N/A #N/A 0.49 U 0.49 U 0.49 U 0.49 U 0.49 * 0.49 U 0.49 U 0.49 U Isopropylbenzene #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Methyl tert-butyl ether #N/A #N/A 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene Chloride #N/A #N/A 1.3 * 1.3 U 1.3 U 1.3 U 1.3 U 1.3 * 1.3 U 1.3 U* m-Xylene & p-Xylene #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Naphthalene 91-20-3 193.5 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.36 J B n-Butylbenzene #N/A #N/A 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U N-Propylbenzene #N/A #N/A 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.13 U 0.19 J B o-Xylene #N/A #N/A 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U sec-Butylbenzene #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.32 J B Styrene #N/A #N/A 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U t-Butylbenzene #N/A #N/A 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.35 J B Tetrachloroethene #N/A #N/A 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U trans-1,2-Dichloroethene #N/A #N/A 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U* trans-1,3-Dichloropropene #N/A #N/A 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene #N/A #N/A 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U* Trichlorofluoromethane #N/A #N/A 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride #N/A #N/A 0.22 U 0.22 U 0.22 U 0.22 U 0.22 * 0.22 U 0.22 U 0.22 U Table 2 - OSU Mosier Report Data vs Columbia River Summary Comparison

Upstream(2) East(3) Compound CAS FCV (µg/L)(1) Min Max Mean Min Max Mean Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 2.60E-01 2.60E-01 2.60E-01 2.68E-03 3.04E-03 2.86E-03 Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 3.00E-03 1.00E-02 6.18E-03 1.64E-04 1.90E-04 1.77E-04 2-Methylnaphthalene 91-57-6 72.16 6.10E-03 2.30E-02 9.59E-03 1.91E-04 2.11E-04 2.01E-04 Acenaphthene 83-32-9 55.85 2.00E-03 6.10E-03 2.51E-03 4.86E-04 5.06E-04 4.96E-04 Acenaphthylene 208-96-8 306.9 2.00E-03 6.10E-03 2.51E-03 3.24E-05 4.80E-05 4.02E-05 Anthracene 120-12-7 20.73 3.00E-03 6.10E-03 3.42E-03 4.36E-05 4.42E-05 4.39E-05 Benz[a]anthracene 56-55-3 2.227 2.00E-03 1.10E-02 2.96E-03 1.70E-05 1.76E-05 1.73E-05 Benzo[a]pyrene 50-32-8 0.9573 3.00E-03 5.80E-03 3.25E-03 2.56E-06 3.50E-06 3.03E-06 Benzo[b]fluoranthene 205-99-2 0.6774 3.00E-03 9.80E-03 8.00E-03 1.64E-05 1.72E-05 1.68E-05 Benzo[ghi]perylene 191-24-2 0.4391 2.60E-03 5.80E-03 3.24E-03 3.92E-06 4.94E-06 4.43E-06 Benzo[k]fluoranthene 207-08-9 0.6415 6.10E-03 1.10E-02 9.11E-03 5.60E-06 6.12E-06 5.86E-06 Chrysene 218-01-9 2.042 6.00E-03 7.30E-03 6.16E-03 4.01E-05 4.30E-05 4.16E-05 Dibenz[a,h]anthracene 53-70-3 0.2825 2.00E-03 7.20E-03 2.40E-03 1.08E-06 1.30E-06 1.19E-06 Fluoranthene 206-44-0 7.109 2.00E-03 9.70E-03 3.34E-03 5.50E-04 6.20E-04 5.85E-04 Fluorene 86-73-7 39.3 3.00E-03 6.30E-03 3.58E-03 3.49E-04 3.88E-04 3.69E-04 Indeno[1,2,3-cd]pyrene 193-39-5 0.275 4.10E-03 8.50E-03 7.07E-03 2.67E-07 3.23E-07 2.95E-07 Naphthalene 91-20-3 193.5 6.10E-03 1.90E-02 1.34E-02 2.68E-03 3.04E-03 2.86E-03 Phenanthrene 85-01-8 19.13 4.00E-03 1.20E-02 6.67E-03 1.07E-03 1.14E-03 1.11E-03 Pyrene 129-00-0 10.11 4.00E-03 1.00E-02 4.86E-03 2.82E-04 2.88E-04 2.85E-04

Notes: (1) FCVs taken from EPA's Procedures for the Derivation of ESBs for the Protection of Benthic Organisms: PAH Mixtures (2003) (2) Grab samples taken from top six inches of water. Sampling occurred from 6/5/16 to 8/15/16. (3) LDPE water samplers deployed approximately 2 feet above mudline. Deployment occurred on 6/24/16 and retrieval on 7/8/16. Table 2 - OSU Mosier Report Data vs Columbia River Summary Comparison

Downstream(2) West(3) Compound CAS FCV (µg/L)(1) Min Max Mean Min Max Mean Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 2.60E-01 1.00E+00 2.90E-01 3.61E-03 4.57E-03 4.09E-03 Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 3.20E-03 1.20E-02 6.27E-03 2.82E-04 3.00E-04 2.91E-04 2-Methylnaphthalene 91-57-6 72.16 6.40E-03 2.50E-02 9.90E-03 2.85E-04 2.99E-04 2.92E-04 Acenaphthene 83-32-9 55.85 2.00E-03 6.40E-03 2.20E-03 3.97E-04 4.41E-04 4.19E-04 Acenaphthylene 208-96-8 306.9 2.00E-03 6.40E-03 2.36E-03 3.75E-05 3.76E-05 3.76E-05 Anthracene 120-12-7 20.73 3.00E-03 1.40E-02 3.56E-03 3.16E-05 4.25E-05 3.71E-05 Benz[a]anthracene 56-55-3 2.227 2.00E-03 4.30E-03 2.20E-03 6.91E-06 1.06E-05 8.76E-06 Benzo[a]pyrene 50-32-8 0.9573 3.00E-03 6.30E-03 3.16E-03 1.62E-06 2.20E-06 1.91E-06 Benzo[b]fluoranthene 205-99-2 0.6774 3.20E-03 8.60E-03 7.80E-03 6.27E-06 1.00E-05 8.14E-06 Benzo[ghi]perylene 191-24-2 0.4391 2.10E-03 4.70E-03 3.05E-03 2.00E-06 3.62E-06 2.81E-06 Benzo[k]fluoranthene 207-08-9 0.6415 6.30E-03 1.00E-02 8.90E-03 2.26E-06 3.74E-06 3.00E-06 Chrysene 218-01-9 2.042 6.00E-03 6.40E-03 6.07E-03 1.45E-05 2.30E-05 1.88E-05 Dibenz[a,h]anthracene 53-70-3 0.2825 2.00E-03 5.40E-03 2.20E-03 1.06E-06 1.75E-06 1.41E-06 Fluoranthene 206-44-0 7.109 2.00E-03 6.20E-03 2.56E-03 3.42E-04 4.96E-04 4.19E-04 Fluorene 86-73-7 39.3 3.00E-03 6.40E-03 3.16E-03 2.86E-04 3.50E-04 3.18E-04 Indeno[1,2,3-cd]pyrene 193-39-5 0.275 4.30E-03 7.50E-03 6.96E-03 2.62E-07 4.34E-07 3.48E-07 Naphthalene 91-20-3 193.5 6.40E-03 3.50E-02 1.38E-02 3.61E-03 4.57E-03 4.09E-03 Phenanthrene 85-01-8 19.13 4.00E-03 9.70E-03 5.15E-03 7.91E-04 1.04E-03 9.16E-04 Pyrene 129-00-0 10.11 4.00E-03 5.00E-03 4.13E-03 1.40E-04 1.85E-04 1.63E-04

Notes: (1) FCVs taken from EPA's Procedures for the Derivation of ESBs for the Protection of Benthic Organisms: PAH Mixtures (2003) (2) Grab samples taken from top six inches of water. Sampling occurred from 6/5/16 to 8/15/16. (3) LDPE water samplers deployed approximately 2 feet above mudline. Deployment occurred on 6/24/16 and retrieval on 7/8/16. Table 2 - OSU Mosier Report Data vs Columbia River Summary Comparison

Source(2) Center(3) Compound CAS FCV (µg/L)(1) Min Max Mean Min Max Mean Volatile Organic Compounds (µg/L) Naphthalene 91-20-3 193.5 2.60E-01 2.60E-01 2.60E-01 3.28E-03 3.77E-03 3.52E-03 Semi-Volatile Organic Compounds (µg/L) 1-Methylnaphthalene 90-12-0 75.37 4.80E-03 2.50E-01 1.74E-02 3.23E-04 4.28E-04 3.63E-04 2-Methylnaphthalene 91-57-6 72.16 6.30E-03 2.70E-01 2.18E-02 3.73E-04 5.14E-04 4.22E-04 Acenaphthene 83-32-9 55.85 2.00E-03 6.30E-03 2.24E-03 3.99E-04 4.34E-04 4.21E-04 Acenaphthylene 208-96-8 306.9 2.00E-03 1.00E-02 2.52E-03 3.69E-05 4.14E-05 3.96E-05 Anthracene 120-12-7 20.73 3.00E-03 4.20E-03 3.14E-03 3.14E-05 3.91E-05 3.43E-05 Benz[a]anthracene 56-55-3 2.227 2.00E-03 4.30E-03 2.21E-03 8.14E-06 1.04E-05 9.09E-06 Benzo[a]pyrene 50-32-8 0.9573 3.00E-03 6.30E-03 3.18E-03 1.41E-06 1.60E-06 1.48E-06 Benzo[b]fluoranthene 205-99-2 0.6774 6.30E-03 9.30E-03 8.05E-03 7.06E-06 9.11E-06 7.80E-06 Benzo[ghi]perylene 191-24-2 0.4391 3.00E-03 4.70E-03 3.12E-03 2.04E-06 2.61E-06 2.34E-06 Benzo[k]fluoranthene 207-08-9 0.6415 6.30E-03 1.00E-02 9.01E-03 2.57E-06 3.22E-06 2.81E-06 Chrysene 218-01-9 2.042 6.00E-03 7.00E-03 6.10E-03 1.66E-05 2.17E-05 1.88E-05 Dibenz[a,h]anthracene 53-70-3 0.2825 2.00E-03 5.40E-03 2.16E-03 8.96E-07 1.13E-06 9.83E-07 Fluoranthene 206-44-0 7.109 2.00E-03 5.50E-03 2.60E-03 3.65E-04 4.52E-04 4.04E-04 Fluorene 86-73-7 39.3 3.00E-03 2.00E-02 3.99E-03 2.82E-04 3.09E-04 2.97E-04 Indeno[1,2,3-cd]pyrene 193-39-5 0.275 4.30E-03 8.10E-03 7.00E-03 2.22E-07 2.81E-07 2.44E-07 Naphthalene 91-20-3 193.5 6.30E-03 9.70E-02 1.68E-02 3.28E-03 3.77E-03 3.52E-03 Phenanthrene 85-01-8 19.13 4.00E-03 4.40E-02 7.16E-03 7.78E-04 8.43E-04 8.14E-04 Pyrene 129-00-0 10.11 4.00E-03 5.80E-03 4.25E-03 1.58E-04 1.88E-04 1.73E-04

Notes: (1) FCVs taken from EPA's Procedures for the Derivation of ESBs for the Protection of Benthic Organisms: PAH Mixtures (2003) (2) Grab samples taken from top six inches of water. Sampling occurred from 6/5/16 to 8/15/16. (3) LDPE water samplers deployed approximately 2 feet above mudline. Deployment occurred on 6/24/16 and retrieval on 7/8/16.

Appendix E Laboratory Analytical Data Packages

Appendix F Boring Logs

PROJECT NUMBER BORING NUMBER 678490 BS-1 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 7/29/2016 DRILLING CONTRACTOR : Environmental West Explorations Western Most Biosparge well ~ 50' from MW-4 DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 8 feet bgs START : 11:20 END : 14:30 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) SYMBOL PID READING = 0.0 ppm

0 ______Brown silty gravel - 3-4 inch rounded to 18" W x 32" L x 24" D Flush _ _ Cemenet Utillity vault and cement _ GM subrounded gravel with occasional cobbles in a silt matrix, dry Well Casing cut 12" BGS to allow _ _ biosparge piping connections _

_ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ _ gravel with silt and sand matrix, poorly 5 ___ graded, loose __ __

_ _ _

_ _ _ _ ˅ WL _ _ 2' to 15' (3/8" Bentonite _ Becomes saturated at ~ 8' _ Chip Seal) _

10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15______GP _ _ _

_ _ _

_ _ _

_ _ _ 15' to 24' (3/8" Bentonite 20 ___ __ Pellets) __

_ _ _

_ _ _

_ Well Completion Details: _ _ _ Casing Material: Sch. 40 PVC _ _ Casing diameter: 2-in 24' to 28' Filter Pack 25 ___ Seal Type: Bentonite Chips (3/8") __ 10x20 Silica Sand __ Filter Media: 10-20 Colorado Silica Sand Screen 25' to 28' _ Screen Length 3' _ _ _ Screen Type: Sch 40 PVC, 0.10" slot _ _ Boring logged by drill cuttings from cyclone _ _ 28' Bottom of Well _ <- 6" -> _ _ _ PROJECT NUMBER BORING NUMBER 678490 BS-2 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 7/30/2016 DRILLING CONTRACTOR : Environmental West Explorations ~24' from BS-1 and 24' from BS-3 DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 6 to 7 feet bgs START : 8:30 END : 10:45 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) SYMBOL PID READING = 0.0 ppm

0 ______Brown silty gravel - 3-4 inch rounded to 18" W x 32" L x 18" D Flush _ _ Cemenet Utillity vault and cement _ GM subrounded gravel with occasional cobbles in a silt matrix, dry Well Casing cut 12" BGS to allow _ _ biosparge piping connections _

_ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ _ gravel with silt and sand matrix, poorly 5 ___ graded, loose __ __

_ _ _ _ ˅ WL _ _

_ Becomes saturated at ~ 7' _ _ 2' to 15' (3/8" Bentonite _ _ Chip Seal) _

10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15______GP _ _ _

_ _ _

_ _ _

_ _ _ 15' to 24' (3/8" Bentonite 20 ___ __ Pellets) __

_ _ _

_ _ _

_ Well Completion Details: _ _ _ Casing Material: Sch. 40 PVC _ _ Casing diameter: 2-in 24' to 28' Filter Pack 25 ___ Seal Type: Bentonite Chips (3/8") __ 10x20 Silica Sand __ Filter Media: 10-20 Colorado Silica Sand Screen 25' to 28' _ Screen Length 3' _ _ _ Screen Type: Sch 40 PVC, 0.10" slot _ _ Boring logged by drill cuttings from cyclone _ _ 28' Bottom of Well _ <- 6" -> _ _ _ PROJECT NUMBER BORING NUMBER 678490 BS-3 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 7/29/2016 DRILLING CONTRACTOR : Environmental West Explorations DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 7 ft bgs START : 7:00 END : 9:30 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) SYMBOL PID READING 0.0

0 ______Brown silty gravel - 3-4 inch rounded to 18" W x 32" L x 18" D Flush _ _ Cemenet Utillity vault and cement _ GM subrounded gravel with occasional cobbles in a silt matrix, dry Well Casing cut 12" BGS to allow _ _ biosparge piping connections _

_ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ _ gravel with silt and sand matrix, poorly 5 ___ graded, loose __ __

_ _ _

_ _ _

_ Becomes saturated at ~ 7' _ _ 2' to 15' (3/8" Bentonite _ _ Chip Seal) _

10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15______GP _ _ _

_ _ _

_ _ _

_ _ _ 15' to 24' (3/8" Bentonite 20 ___ __ Pellets) __

_ _ _

_ _ _

_ Well Completion Details: _ _ _ Casing Material: Sch. 40 PVC _ _ Casing diameter: 2-in 24' to 28' Filter Pack 25 ___ Seal Type: Bentonite Chips (3/8") __ 10x20 Silica Sand __ Filter Media: 10-20 Colorado Silica Sand Screen 25' to 28' _ Screen Length 3' _ _ _ Screen Type: Sch 40 PVC, 0.10" slot _ _ Boring logged by drill cuttings from cyclone _ _ 28' Bottom of Well _ <- 6" -> _ _ _ PROJECT NUMBER BORING NUMBER 678490 BS-4 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 7/28/2016 DRILLING CONTRACTOR : Environmental West Explorations DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 6 to 7 feet bgs START: 13:20 END: 15:00 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) SYMBOL PID READING ~0.1 ppm

0 ______Brown silty gravel - 3-4 inch rounded to 18" W x 32" L x 18" D Flush _ _ Cemenet Utillity vault and cement _ GM subrounded gravel with occasional cobbles in a silt matrix, dry Well Casing cut 12" BGS to allow _ _ biosparge piping connections _

_ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ _ gravel with silt and sand matrix, poorly 5 ___ graded, loose __ __

_ _ _ _ ˅ WL _ _

_ Becomes saturated at ~ 7' _ _ 2' to 15' (3/8" Bentonite _ _ Chip Seal) _

10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15______GP _ _ _

_ _ _

_ _ _

_ _ _ 15' to 24' (3/8" Bentonite 20 ___ __ Pellets) __

_ _ _

_ _ _

_ Well Completion Details: _ _ _ Casing Material: Sch. 40 PVC _ _ Casing diameter: 2-in 24' to 28' Filter Pack 25 ___ Seal Type: Bentonite Chips (3/8") __ 10x20 Silica Sand __ Filter Media: 10-20 Colorado Silica Sand Screen 25' to 27.9' _ Screen Length 3' _ _ _ Screen Type: Sch 40 PVC, 0.10" slot _ _ Boring logged by drill cuttings from cyclone _ _ 27.9' Bottom of Well _ <- 4" -> _ Developed by pumping 25 gallons _ _ PROJECT NUMBER BORING NUMBER 678490 BS-5 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 7/27/2016 - 7/28/16 DRILLING CONTRACTOR : Environmental West Explorations Eastern most biosparge well DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 7' bgs START: 14:20 END: 8:30 AM LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) SYMBOL PID READING 0.0

0 ______Brown silty gravel - 3-4 inch rounded to 18" W x 32" L x 18" D Flush _ _ Cemenet Utillity vault and cement _ GM subrounded gravel with occasional cobbles in a silt matrix, dry Well Casing cut 12" BGS to allow _ _ biosparge piping connections _

_ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ _ gravel with silt and sand matrix, poorly 5 ___ graded, loose __ __

_ _ 2' to 10' ( 2 bags 3/8" _ Bentonite Chip Seal) _ _ _

_ Becomes saturated at ~ 7' _ _

_ _ _

10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15______GP _ _ _

_ _ 10' to 24' (5 buckets 3/8" _ Bentonite Pellets) _ _ _

_ _ _

20 ______

_ _ _

_ _ _

_ Well Completion Details: _ _ Casing Material: Sch. 40 PVC _ _ _ Casing diameter: 2-in 23.7' to 27.8' Filter Pack 4 bags 25 ___ Seal Type: Bentonite Chips (3/8") __ of 10x20 Silica Sand __ Filter Media: 10-20 Colorado Silica Sand Screen 25' to 27.8' _ Screen Length 3' _ _ Screen Type: Sch 40 PVC, 0.10" slot _ _ _ Boring logged by drill cuttings from cyclone _ _ 27.8' Bottom of Well _ <- 6" -> _ Developed by pumping 20 gallons _ _ PROJECT NUMBER BORING NUMBER 678490 EW-1 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 6/13/2016 DRILLING CONTRACTOR : Environmental West Explorations DRILLING METHOD AND EQUIPMENT USED : Air Rotary B-90 WATER LEVELS : 22.85 feet START : 14:00 END : 16:10 LOGGER : DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, MOISTURE CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER USCS GROUP CONTENT, RELATIVE DENSITY OR CONSISTENCY, SOIL SAND TYPE SYMBOL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING

0 ______GP 12" flush-mount vault and _ 2-inch minus gravel fill _ cement seal (to 1.0' bgs) _

_ _ _

_ _ 0.1 _ GP Dry compacted clean gravel fill _ _ _

5 ______

_ _ _ As above _ _ _

_ _ 17.0' to 2.0' Bentonite Chip 0 _ Seal _ _ _ GP 10 ______

_ _ _

_ _ _

_ _ _ Grayish-Brown silty sandy gravel - silt matrix with 3- _ 4" rounded to subrounded poorly graded gravel, f- _ _ m sand, no odor, no sheen (fill?), moist 15______

_ _ _

_ _ 0.2 _ 17.0' to 36.0' Filter Pack _ _ _ As above _ _ _

20 ______20' Top Depth of Screen Increase in moisture at 20' _ _ _

_ _ _

_ Becomes saturated at 22' _ _ 0.1 _ no sheen observed _ _

25 ______GM _ _ _

_ _ _

_ _ _

_ _ _

30 ______

_ Increase in f-c sand at 30' _ _

_ _ _

_ _ _

_ _ 0 _

35 ___ Increase in fines at 35' __ 35' Bottom Depth of __ Screen _ _ _

_ _

_ Grayish Brown clayey gravel - clay matrix with _ occasional f-c angular basalt fragments, no odor, GC _ no sheen, saturated. Drilling becomes hard at __ _ 39.5' 0 40 ______<- 8" -> Well Completion Details: Boring logged by drill cuttings from cyclone Casing Material: Sch. 40 PVC Casing diameter: 4-in Seal Type: Bentonite Chips Filter Media: 10-20 Colorado Silica Sand Screen Length 15' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 EW-2 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 6/15/2016 DRILLING CONTRACTOR : Environmental West Explorations DRILLING METHOD AND EQUIPMENT USED : Air Rotary B-90 WATER LEVELS : 22.06 feet START : 14:20 END : 16:45 LOGGER : DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, MOISTURE CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER USCS GROUP CONTENT, RELATIVE DENSITY OR CONSISTENCY, SOIL SAND TYPE SYMBOL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING

0 ______12" flush-mount vault and GP _ 2-inch minus gravel fill _ cement seal (to 1.0' bgs) _

_ _ _ Dry compacted clean gravel fill GP _ _ 0.1 _

_ _ _ Reddish-Brown silty gravel - silt matrix with angular 5 ___ basalt gravel, poorly graded, no odor, no sheen, __ __ moist, occasional f-m sand in matrix _ _ _

_ _ _

_ _ 13.0' to 2.0' Bentonite Chip 0 _ Seal GM _ _ _

10 ______

_ _ _ Increase in f-m sand at 12' _ _ _

_ _ _ 13.0' to 36.0' Filter Pack Reddish-Brown silty sandy gravel - silt and f-m _ sand matrix with angular basalt gravel, poorly _ _ graded, no odor, no sheen, moist 15______15' Top Depth of Screen _ _ _

_ _ 0.2 _

_ _ _

_ _ _

20 ______Increase in moisture at 21' _ _ _

_ _ _

_ Becomes saturated at 22' _ _ GM 0.1 _ no sheen observed _ _

25 ______

_ _ _

_ _ _

_ _ _

_ _ _

30 ______

_ Increase of f-c sand at 30' _ _

_ _ _

_ _ _ Brown to Reddish brown sandy gravel - f-c angular _ to subangular sand with f-m gravel. Gravel is _ 0 _ GP subangular consisting of basalt with quartz 35 ___ __ 35' Bottom Depth of __ (alluvium), poorly graded, no odor, no sheen, Screen _ saturated _ _ Well Completion Details: Boring logged by drill cuttings from the cyclone Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips Filter Media: 10-20 Colorado Silica Sand Screen Length 20' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-1 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 6/16/2016 DRILLING CONTRACTOR : Cascade Drilling DRILLING METHOD AND EQUIPMENT USED : Sonic track mount WATER LEVELS : 14.8 feet START : 10:30 END : 11:30 LOGGER : DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, MOISTURE CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER USCS GROUP CONTENT, RELATIVE DENSITY OR CONSISTENCY, SOIL SAND TYPE SYMBOL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING

0 ______12" flush-mount vault and _ Brown silty gravel - 3-4 inch rounded to subrounded _ cement seal (to 1.0' bgs) _ GM gravel with occasional cobbles in a silt matrix, dry _ (fill?) _ _ 5.0' to 1.0' Bentonite Chip _ _ Seal 0.1 _ Grayish-Brown gravel - 1-inch subrounded gravel _ with silt and f-m sand matrix, poorly graded, loose, _ _ dry. 5 ______

_ _ _

_ _ _ 7' Top Depth of Screen _ _ 0 _

_ _ _

10 ______

_ _ _ Increase in moisture at 12' _ _ _

_ GP _ _ 5.0' to 23.0' Filter Pack Saturated at approximately 14' during drilling _ _ _

15______

_ _ _

_ _ 0.2 _

_ _ _

_ _ _ Brown to Reddish brown sandy gravel - f-c angular 20 ___ to subangular sand with f-m gravel. Gravel is __ __ subangular consisting of basalt with quartz _ (alluvium), poorly graded, no odor, no sheen, _ _ saturated _ _ _ 22' Bottom Depth of Screen

_ _ _ Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips Filter Media: 10-20 Colorado Silica Sand Screen Length 15' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-2 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 6/17/2016 DRILLING CONTRACTOR : Cascade Drilling DRILLING METHOD AND EQUIPMENT USED : Sonic track mount WATER LEVELS : 10.6 feet START : 10:30 END : 11:30 LOGGER : DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, MOISTURE CASING MATERIAL, SCREEN TYPE, SEAL TYPE, USCS GROUP CONTENT, RELATIVE DENSITY OR CONSISTENCY, SOIL FILTER SAND TYPE SYMBOL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING

0 ______12" flush-mount vault and _ Brown silty gravel - 3-4 inch rounded to _ cement seal (to 1.0' bgs) _ GM subrounded gravel with occasional cobbles in a silt _ matrix, dry _ _ 4.0' to 1.0' Bentonite Chip _ _ Seal 0.1 _ Grayish-Brown gravel - 1-inch subrounded gravel _ with silt and f-m sand matrix, poorly graded, loose, _ _ dry. 5 ______5' Top Depth of Screen _ _ _

_ _ _

_ _ 0 _ Increase of moisture at 9' _ _ _

10 ______

_ _ _ GP Grades to Brown to Grayish Brown Gravel - f-c _ angular to subangular sand with silt. Gravel is _ _ angular to subrounded (1-3") alluvium, poorly _ _ _ graded, no odor, no sheen, saturated 4.0' to 21.0' Filter Pack _ _ _

15______

_ Increase of f-m sand _ _

_ _ 0.2 _ As Above - Brown to Grayish Brown Gravel - f-c _ angular to subangular sand with silt. Gravel is _ _ angular to subrounded (1-3") alluvium, poorly _ graded, no odor, no sheen, saturated _ _ 20 ______20' Bottom Depth of Screen _ _ _ Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips Filter Media: 10-20 Colorado Silica Sand Screen Length 15' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-3 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 6/17/2016 DRILLING CONTRACTOR : Cascade Drilling DRILLING METHOD AND EQUIPMENT USED : Sonic track mount WATER LEVELS : 10.0 feet START : 08:00 END : 9:00 LOGGER : DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, MOISTURE CASING MATERIAL, SCREEN TYPE, SEAL TYPE, USCS GROUP CONTENT, RELATIVE DENSITY OR CONSISTENCY, SOIL FILTER SAND TYPE SYMBOL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING

0 ______12" flush-mount vault and _ Brown silty gravel - 3-4 inch rounded to _ cement seal (to 1.0' bgs) _ GM subrounded gravel with occasional cobbles in a silt _ matrix, dry _ _ 4.0' to 1.0' Bentonite Chip _ _ Seal 0.1 _ Grayish-Brown gravel - 1-inch subrounded gravel _ with silt and f-m sand matrix, poorly graded, loose, _ _ dry. 5 ______5' Top Depth of Screen _ _ _

_ _ _

_ _ 0 _ Increase of moisture at 9' _ _ _

10 ______

_ _ _ GP Grades to Brown to Grayish Brown Gravel - f-c _ angular to subangular sand with silt. Gravel is _ _ angular to subrounded (1-3") alluvium, poorly _ _ _ graded, no odor, no sheen, saturated 4.0' to 21.0' Filter Pack _ _ _

15______

_ Increase of fines at 18' _ _

_ _ 0.2 _

_ _ _ Brown to Grayish Brown Gravel - f-c angular to _ subangular sand with silt. Higher fines content than _ _ above. Gravel is angular to subrounded (1-3") 20 ______alluvium, poorly graded, no odor, no sheen, 20' Bottom Depth of Screen saturated _ _ _ Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips Filter Media: 10-20 Colorado Silica Sand Screen Length 15' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-4 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 6/16/2016 DRILLING CONTRACTOR : Cascade Drilling DRILLING METHOD AND EQUIPMENT USED : Sonic track mount WATER LEVELS : 6.0 feet START : 14:45 END : 15:30 LOGGER : DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, MOISTURE CASING MATERIAL, SCREEN TYPE, SEAL TYPE, USCS GROUP CONTENT, RELATIVE DENSITY OR CONSISTENCY, SOIL FILTER SAND TYPE SYMBOL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING

0 ______12" flush-mount vault and _ Brown silty gravel - 3-4 inch rounded to _ cement seal (to 1.0' bgs) _ GM subrounded gravel with occasional cobbles in a silt _ matrix, dry _ _ 4.0' to 1.0' Bentonite Chip _ _ Seal 0.1 _ Grayish-Brown gravel - 1-inch subrounded gravel _ with silt and f-m sand matrix, poorly graded, loose, _ _ Increase of moisture at 5' 5 ______5' Top Depth of Screen _ _ _ Becomes saturated at 6' _ _ _ GP _ _ 0 _

_ _ _

10 ______

_ _ _

_ _ _

_ _ _ 4.0' to 16.0' Filter Pack Grades to Brown Silt - Silt (soft) with occasional _ basalt gravel. Gravel is angular to subrounded (1") _ _ ML alluvium, poorly graded, no odor, no sheen, 15___ saturated __ 15' Bottom Depth of Screen __ GP Grades to Grayish Brown Gravel - f-c angular to _ subangular sand with silt. Gravel is angular to _ _ subrounded (1-3") alluvium, poorly graded, no _ odor, no sheen, saturated _ _ _ _ Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips Filter Media: 10-20 Colorado Silica Sand Screen Length 10' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-5 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 7/28/2016 DRILLING CONTRACTOR : Environmental West Explorations Eastern well ~ 20' from BS-5 DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : ~ 5 ft bgs START : 13:00 END : 14:00 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) SYMBOL PID READING 30-40 ppm

0 ______12" flush-mount vault and _ Brown silty gravel - 3-4 inch rounded to _ _ GM subrounded gravel with occasional cobbles in cement seal (to 1.0' bgs). Set ~ 6" above grade. _ a silt matrix, dry _ _

_ _ 1.0' to 4.0' (3/8" Bentonite _ Chip Seal) _ Grayish-Brown gravel - 1-inch subrounded _ _ gravel with silt and sand matrix, poorly graded, GP 5 ___ loose __ __ 5' Top Depth of Screen _ _ _

_ Becomes saturated at ~ 5' _ _

_ _ _

_ _ 4.0' to 15.0' Filter Pack _ 10x20 Silica Sand 10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15___ End of boring __ 15' Bottom Depth of Screen __ <- 6" -> _ _ _

_ _ _

_ _ _ Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips (3/8") Filter Media: 10-20 Colorado Silica Sand Screen Length 10' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-6 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR Date Drilled: 7/28/2016 DRILLING CONTRACTOR : Environmental West Explorations Eastern Most well ~ 10' from BS-5 DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 5 ft bgs START : 9:55 END : 11:30 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM SAMPLE INTERVAL (FT) SOIL NAME, USCS GROUP SYMBOL, COLOR, USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, MOISTURE CONTENT, RELATIVE DENSITY OR GROUP FILTER SAND TYPE CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) SYMBOL PID READING 0.0

0 ______12" flush-mount vault and _ _ _ GM cement seal (to 1.0' bgs). Set ~ 6" above grade. _ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ 1.0' to 4.0' (3/8" Bentonite _ gravel with silt and sand matrix, poorly graded, Chip Seal) _ loose _ _

5 ______5' Top Depth of Screen _ Becomes saturated at ~ 5' _ _

_ _ _

_ _ _ GP _ _ 4.0' to 15.0' Filter Pack _ 10x20 Silica Sand 10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15___ End of boring __ 15' Bottom Depth of Screen __ <- 6" -> _ _ _

_ _ _ Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips (3/8") Filter Media: 10-20 Colorado Silica Sand Screen Length 10' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-7 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR ~25' North of BS Date Drilled: 7/30/2016 DRILLING CONTRACTOR : Environmental West Explorations DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 5 ft bgs START : 6:50 END : 8:00 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM

SOIL NAME, USCS GROUP SYMBOL, COLOR, SAMPLE INTERVAL (FT) USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE SYMBOL CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING 0.0 Above Ground Completion, _ _ monument stickup ~4'

_ _ ~4' _ _

0 ______Brown silty gravel - 3-4 inch rounded to _ _ Concrete Surface Seal and Pad _ GM subrounded gravel with occasional cobbles in a silt matrix, dry _ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ 2' to 5' (3/8" Bentonite Chip _ gravel with silt and sand matrix, poorly Seal) _ graded, loose _ _ 5 ___ ˅ WL __ __ 5' Top Depth of Screen _ Becomes saturated at ~ 5' _ _

_ _ _

_ _ _ GP _ _ 5.0' to 15.0' Filter Pack _ 10x20 Silica Sand 10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15___ End of boring __ 15' Bottom of Well __ <- 6" -> _ _ _

_ _ _

Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips (3/8") Filter Media: 10-20 Colorado Silica Sand Screen Length 10' Screen Type: Sch 40 PVC, 0.10" slot PROJECT NUMBER BORING NUMBER 678490 MW-8 SHEET 1 OF 1 SOIL BORING LOG and WELL CONSTRUCTION

PROJECT : UPRR Mosier Derailment LOCATION : Mosier, OR ~100' North of MW-4 Date Drilled: 7/30/2016 DRILLING CONTRACTOR : Environmental West Explorations DRILLING METHOD AND EQUIPMENT USED : Air Rotary WATER LEVELS : 5 ft bgs START : 15:00 END : 16:00 LOGGER Brandon Jones-Stanley DEPTH BELOW SURFACE (FT) CORE DESCRIPTION WELL CONSTRUCTION DIAGRAM

SOIL NAME, USCS GROUP SYMBOL, COLOR, SAMPLE INTERVAL (FT) USCS CASING MATERIAL, SCREEN TYPE, SEAL TYPE, FILTER MOISTURE CONTENT, RELATIVE DENSITY OR GROUP SAND TYPE SYMBOL CONSISTENCY, SOIL STRUCTURE, MINERALOGY. RECOVERY (FT) PID READING 0.0 Above Ground Completion, _ _ monument stickup ~4'

_ _ ~4' _ _

0 ______Brown silty gravel - 3-4 inch rounded to _ _ Concrete Surface Seal and Pad _ GM subrounded gravel with occasional cobbles in a silt matrix, dry _ _ _

_ Grayish-Brown gravel - 1-inch subrounded _ 2' to 5' (3/8" Bentonite Chip _ gravel with silt and sand matrix, poorly Seal) _ graded, loose _ _ 5 ___ ˅ WL __ __ 5' Top Depth of Screen _ Becomes saturated at ~ 5' _ _

_ _ _

_ _ _ GP _ _ 5.0' to 15.0' Filter Pack _ 10x20 Silica Sand 10 ______

_ _ _

_ _ _

_ _ _

_ _ _

15___ End of boring __ 15' Bottom of Well __ <- 6" -> _ _ _

_ _ _

Well Completion Details: Casing Material: Sch. 40 PVC Casing diameter: 2-in Seal Type: Bentonite Chips (3/8") Filter Media: 10-20 Colorado Silica Sand Screen Length 10' Screen Type: Sch 40 PVC, 0.10" slot

Appendix G Previous Groundwater Sample Results

Table G‐1 Groundwater Sample Results ‐ 6/14/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW‐1MW‐1 Dup Sample Date 6/14/16 9:15 6/14/16 9:15 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 1.0 U 1.0 U 1,1,1‐Trichloroethane 1.0 U 1.0 U 1,1,2,2‐Tetrachloroethane 1.0 U 1.0 U 1,1,2‐Trichloroethane 1.0 U 1.0 U 1,1‐Dichloroethane 1.0 U 1.0 U 1,1‐Dichloroethene 2.0 U 2.0 U 1,1‐Dichloropropene 1.0 U 1.0 U 1,2,3‐Trichlorobenzene 5.0 U 5.0 U 1,2,3‐Trichloropropane 1.0 U 1.0 U 1,2,4‐Trichlorobenzene 2.0 U 2.0 U 1,2,4‐Trimethylbenzene 1.0 U 1.0 U 1,2‐Dibromo‐3‐Chloropropane 1.0 U 1.0 U 1,2‐Dibromoethane 0.01 U 0.01 U 1,2‐Dichlorobenzene 1.0 U 1.0 U 1,2‐Dichloroethane 1.0 U 1.0 U 1,2‐Dichloropropane 1.0 U 1.0 U 1,3,5‐Trimethylbenzene 1.0 U 1.0 U 1,3‐Dichlorobenzene 1.0 U 1.0 U 1,3‐Dichloropropane 1.0 U 1.0 U 1,4‐Dichlorobenzene 1.0 U 1.0 U 2,2‐Dichloropropane 2.0 U 2.0 U 2‐Chlorotoluene 1.0 U 1.0 U 4‐Chlorotoluene 1.0 U 1.0 U Benzene 3 2.7 Bromobenzene 1.0 U 1.0 U Bromodichloromethane 1.0 U 1.0 U Bromoform 1.0 U 1.0 U Bromomethane 2.0 U 2.0 U Carbon tetrachloride 1.0 U 1.0 U Chlorobenzene 1.0 U 1.0 U Chloroethane 2.0 U 2.0 U Chloroform 1.0 U 1.0 U Chloromethane 2.0 U 2.0 U cis‐1,2‐Dichloroethene 1.0 U 1.0 U cis‐1,3‐Dichloropropene 1.0 U 1.0 U Dibromochloromethane 1.0 U 1.0 U Table G‐1 Groundwater Sample Results ‐ 6/14/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW‐1MW‐1 Dup Sample Date 6/14/16 9:15 6/14/16 9:15 Dibromomethane 1.0 U 1.0 U Dichlorodifluoromethane 2.0 U 2.0 U Ethylbenzene 1.0 U 1.0 U Hexachloro‐1,3‐butadiene 5.0 U 5.0 U Isopropylbenzene 4.0 U 4.0 U Isopropyltoluene 1.0 U 1.0 U Methyl tert‐Butyl Ether (MTBE) 5.0 U 5.0 U Methylene chloride 1.0 U 1.0 U Naphthalene 5.0 U 5.0 U n‐Butylbenzene 1.0 U 1.0 U n‐Propylbenzene 1.0 U 1.0 U sec‐Butylbenzene 1.0 U 1.0 U Styrene 1.0 U 1.0 U tert‐Butylbenzene 1.0 U 1.0 U Tetrachloroethene (PCE) 1.0 U 1.0 U Toluene 2.6 2.3 Total Xylenes 2.0 U 2.0 U trans‐1,2‐Dichloroethene 1.0 U 1.0 U Trans‐1,3‐Dichloropropene 1.0 U 1.0 U Trichloroethene (TCE) 1.0 U 1.0 U Trichlorofluoromethane 2.0 U 2.0 U Vinyl chloride 0.2 U 0.2 U NWTPH (mg/L) Gasoline 0.1 U 0.1 U Notes: Sample was collected as a grab sample, and is not representative of actual aquifer conditions. Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed U = Analyte was not detected above the MDL Table G‐2 Groundwater Sample Results ‐ 6/24/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐062416 MW2‐062416 MW3‐062416 MW4‐062416 EW1‐062416 DUP‐062416 EW2‐062416 Sample Date 6/24/16 11:40 6/24/16 8:40 6/24/16 9:40 6/24/16 10:45 6/24/16 12:45 6/24/16 12:00 6/24/16 13:45 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.66 J 0.25 U 0.25 U 90 8.9 12 3.2 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 1J 0.27 U 0.27 U 130 J 0.95 J 0.96 J 2.9 J 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 42 2.6 J 3.7 1 J 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 5.2 0.26 U 0.26 U 0.26 U Benzene 0.91 J 0.42 U 0.42 U 520 62 81 9.9 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U

Page 4 of 44 Table G‐2 Groundwater Sample Results ‐ 6/24/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐062416 MW2‐062416 MW3‐062416 MW4‐062416 EW1‐062416 DUP‐062416 EW2‐062416 Sample Date 6/24/16 11:40 6/24/16 8:40 6/24/16 9:40 6/24/16 10:45 6/24/16 12:45 6/24/16 12:00 6/24/16 13:45 Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.31 J 0.21 U 0.21 U 81 1.1 J 1.4 J 1.6 J Hexachlorobutadiene ‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 19 0.41 J 0.53 J 0.3 U Isopropyltoluene ‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 1.3 J 0.3 U 0.3 U 310 5.7 7.2 7.6 Naphthalenes 2.8 U 0.26 U 0.26 U 23 2U 2U 2U n‐Butylbenzene 0.43 J 0.3 U 0.3 U 25 0.3 U 1.5 J 0.3 U n‐Propylbenzene 0.14 J 0.13 U 0.13 U 17 0.18 J 0.19 J 0.21 J o‐Xylene 0.59 J 0.49 U 0.49 U 150 J 23 31 7 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 4.6 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.51 J 0.36 U 0.36 U 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.42 J 0.27 U 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 1.3 J 0.18 U 0.18 U 590 24 32 13 Total Xylenes ‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U

Page 5 of 44 Table G‐2 Groundwater Sample Results ‐ 6/24/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐062416 MW2‐062416 MW3‐062416 MW4‐062416 EW1‐062416 DUP‐062416 EW2‐062416 Sample Date 6/24/16 11:40 6/24/16 8:40 6/24/16 9:40 6/24/16 10:45 6/24/16 12:45 6/24/16 12:00 6/24/16 13:45 Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.012 J 0.0062 U 0.0074 J 12 0.67 0.71 0.0065 J 2‐Methylnaphthalene 0.0091 U 0.0093 U 0.0091 U 9.1 0.05 J 0.0092 UJ 0.01 J Acenaphthene 0.002 U 0.0066 J 0.0056 J 0.076 0.0072 J 0.0078 J 0.002 U Acenaphthylene 0.002 U 0.0021 U 0.002 U 0.21 0.031 0.033 0.002 U Anthracene 0.003 U 0.0031 U 0.003 U 0.0032 U 0.003 U 0.0031 U 0.003 U Benzo[a]anthracene 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.0031 U 0.003 U 0.0032 U 0.003 U 0.0031 U 0.003 U Benzo[b]fluoranthene 0.0081 U 0.0083 U 0.0081 U 0.0086 U 0.0081 U 0.0082 U 0.0081 U Benzo[g,h,i]perylene 0.003 U 0.0031 U 0.003 U 0.0032 U 0.003 U 0.0031 U 0.003 U Benzo[k]fluoranthene 0.0091 U 0.0093 U 0.0091 U 0.0097 U 0.0091 U 0.0092 U 0.0091 U Chrysene 0.0061 U 0.0062 U 0.0061 U 0.0064 U 0.006 U 0.0061 U 0.006 U Dibenz(a,h)anthracene 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0074 J Fluorene 0.003 U 0.0031 U 0.003 U 0.35 0.033 0.032 0.003 U Indeno[1,2,3‐cd]pyrene 0.0071 U 0.0073 U 0.0071 U 0.0075 U 0.0071 U 0.0071 U 0.0071 U Naphthalene 0.013 J 0.026 J 0.016 J 8.7 0.34 0.36 0.013 U Phenanthrene 0.011 J 0.011 J 0.012 J 0.26 0.034 0.035 0.016 J Pyrene 0.0041 U 0.0042 U 0.004 U 0.0043 U 0.004 U 0.0041 U 0.009 J

Page 6 of 44 Table G‐2 Groundwater Sample Results ‐ 6/24/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐062416 MW2‐062416 MW3‐062416 MW4‐062416 EW1‐062416 DUP‐062416 EW2‐062416 Sample Date 6/24/16 11:40 6/24/16 8:40 6/24/16 9:40 6/24/16 10:45 6/24/16 12:45 6/24/16 12:00 6/24/16 13:45 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 5.1 J 0.31 J 0.48 J 0.14 #2 Diesel (C10‐C24) 0.11 U 0.11 U 0.11 U 0.49 0.15 U 0.15 U 0.14 U Motor Oil (>C24‐C36) 0.03 U 0.03 U 0.029 U 0.032 J 0.03 U 0.029 U 0.029 U Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 7 of 44 Table G‐3 Groundwater Sample Results ‐ 6/30/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐063016 MW2‐063016 MW3‐063016 MW4‐063016 EW1‐063016 EW2‐063016 Sample Date 6/30/16 10:05 6/30/16 10:50 6/30/16 11:30 6/30/16 12:20 6/30/16 8:25 6/30/16 9:10 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.52 J 0.25 U 0.25 U 130 20 1.6 J 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.83 J 0.27 U 0.27 U 220 13 1.1 J 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 56 6.4 0.41 J 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 6.4 0.5 J 0.26 U Benzene 0.87 J 0.42 U 0.42 U 1,800 160 10 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U

Page 8 of 44 Table G‐3 Groundwater Sample Results ‐ 6/30/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐063016 MW2‐063016 MW3‐063016 MW4‐063016 EW1‐063016 EW2‐063016 Sample Date 6/30/16 10:05 6/30/16 10:50 6/30/16 11:30 6/30/16 12:20 6/30/16 8:25 6/30/16 9:10 Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.31 J 0.21 U 0.21 U 140 9.9 0.87 J Hexachlorobutadiene ‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 34 1.8 J 0.3 U Isopropyltoluene ‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 1.3 J 0.3 U 0.3 U 630 49 3.6 Naphthalene 1.5 J 0.26 U 0.26 U 37 5.9 J 0.48 J n‐Butylbenzene 0.3 U 0.3 U 0.3 U 33 2.5 J 0.3 U n‐Propylbenzene 0.13 U 0.13 U 0.13 U 25 1.1 J 0.13 U o‐Xylene 0.49 J 0.49 U 0.49 U 360 55 3.7 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 6.1 0.34 J 0.27 U Styrene 0.36 U 0.36 U 0.36 U 1.4 J 0.36 U 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.51 J 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 1.3 J 0.24 J 0.18 U 1,600 110 9.2 Total Xylenes ‐‐‐‐‐‐

Page 9 of 44 Table G‐3 Groundwater Sample Results ‐ 6/30/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐063016 MW2‐063016 MW3‐063016 MW4‐063016 EW1‐063016 EW2‐063016 Sample Date 6/30/16 10:05 6/30/16 10:50 6/30/16 11:30 6/30/16 12:20 6/30/16 8:25 6/30/16 9:10 trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.006 U 0.006 U 0.0061 U 26 3 0.006 U 2‐Methylnaphthalene 0.0091 U 0.009 U 0.0091 U 29 2.1 0.009 U Acenaphthene 0.002 U 0.002 U 0.002 U 0.1 0.017 J 0.002 U Acenaphthylene 0.002 U 0.002 U 0.002 U 0.29 0.12 0.002 U Anthracene 0.003 U 0.003 U 0.003 U 0.019 J 0.003 U 0.003 U Benzo[a]anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.0081 U 0.008 U 0.0081 U 0.0081 U 0.008 U 0.008 U Benzo[g,h,i]perylene 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.0091 U 0.009 U 0.0091 U 0.0091 U 0.009 U 0.009 U Chrysene 0.006 U 0.006 U 0.0061 U 0.0061 U 0.006 U 0.006 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluorene 0.003 U 0.003 U 0.003 U 0.48 0.077 0.003 U Indeno[1,2,3‐cd]pyrene 0.0071 U 0.007 U 0.0071 U 0.0071 U 0.007 U 0.007 U Naphthalene 0.031 J 0.036 J 0.033 J 19 3.3 0.013 U Phenanthrene 0.0069 J 0.009 J 0.0096 J 0.69 0.09 0.0042 J Pyrene 0.004 U 0.004 U 0.0041 U 0.019 J 0.004 U 0.004 U

Page 10 of 44 Table G‐3 Groundwater Sample Results ‐ 6/30/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐063016 MW2‐063016 MW3‐063016 MW4‐063016 EW1‐063016 EW2‐063016 Sample Date 6/30/16 10:05 6/30/16 10:50 6/30/16 11:30 6/30/16 12:20 6/30/16 8:25 6/30/16 9:10 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 9.9 J 0.95 0.077 #2 Diesel (C10‐C24) 0.023 J 0.035 J 0.034 J 0.98 0.26 0.11 Motor Oil (>C24‐C36) 0.03 U 0.029 U 0.029 U 0.075 J 0.029 U 0.35 Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 11 of 44 Table G‐4 Groundwater Sample Results ‐ 7/8/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐070816 MW2‐070816 MW3‐070816 MW4‐070816 EW1‐070816DUP‐070816 EW2‐070816 Sample Date 7/8/16 10:30 7/8/16 11:10 7/8/16 11:55 7/8/16 13:00 7/8/16 14:05 7/8/16 12:00 7/8/16 15:10 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 120 J 0.62 J 0.25 U 1.1 J 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 170 J 0.87 J 0.27 U 1.5 J 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.22 J 0.16 U 0.16 U 0.16 U 0.16 J 0.17 J 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 56 0.27 J 0.26 U 0.44 J 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 5.9 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.49 J 0.42 U 1,800 1J 1J 1J Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.27 J 0.23 J

Page 12 of 44 Table G‐4 Groundwater Sample Results ‐ 7/8/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐070816 MW2‐070816 MW3‐070816 MW4‐070816 EW1‐070816DUP‐070816 EW2‐070816 Sample Date 7/8/16 10:30 7/8/16 11:10 7/8/16 11:55 7/8/16 13:00 7/8/16 14:05 7/8/16 12:00 7/8/16 15:10 Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 130 J 0.21 U 0.21 U 0.67 J Hexachlorobutadiene ‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 29 0.3 U 0.3 U 0.3 U Isopropyltoluene ‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 580 1.3 J 0.35 J 2.4 J Naphthalene 0.26 U 0.26 U 0.26 U 44 J 0.5 J 0.26 U 0.39 J n‐Butylbenzene 0.3 U 0.3 U 0.3 U 31 0.3 U 0.3 U 0.35 J n‐Propylbenzene 0.13 U 0.13 U 0.13 U 24 0.16 J 0.13 U 0.19 J o‐Xylene 0.49 U 0.49 U 0.49 U 310 0.68 J 0.49 U 1.9 J sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 5.7 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 1.2 J 0.36 U 0.36 U 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.49 J 0.27 U 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.32 J 0.18 U 1500 1.3 J 0.6 J 3.3 Total Xylenes ‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U

Page 13 of 44 Table G‐4 Groundwater Sample Results ‐ 7/8/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐070816 MW2‐070816 MW3‐070816 MW4‐070816 EW1‐070816DUP‐070816 EW2‐070816 Sample Date 7/8/16 10:30 7/8/16 11:10 7/8/16 11:55 7/8/16 13:00 7/8/16 14:05 7/8/16 12:00 7/8/16 15:10 Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0062 U 0.0065 U 0.0062 U 20 0.0061 U 0.0062 U 0.12 2‐Methylnaphthalene 0.0093 U 0.0097 U 0.0094 U 21 0.0092 U 0.0093 U 0.092 Acenaphthene 0.0021 U 0.0045 J 0.0021 U 0.12 0.002 U 0.0021 U 0.0021 U Acenaphthylene 0.0021 U 0.0022 U 0.0021 U 0.27 0.002 U 0.0021 U 0.0021 U Anthracene 0.0031 U 0.0032 U 0.0031 U 0.0099 J 0.0031 U 0.0031 U 0.0031 U Benzo[a]anthracene 0.0021 U 0.0022 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.0021 U Benzo[a]pyrene 0.0031 U 0.0032 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[b]fluoranthene 0.0082 U 0.0087 U 0.0083 U 0.0082 U 0.0081 U 0.0082 U 0.0083 U Benzo[g,h,i]perylene 0.0031 U 0.0032 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[k]fluoranthene 0.0093 U 0.0097 U 0.0094 U 0.0093 U 0.0092 U 0.0093 U 0.0093 U Chrysene 0.0062 U 0.0065 U 0.0062 U 0.0062 U 0.0061 U 0.0062 U 0.0062 U Dibenz(a,h)anthracene 0.0021 U 0.0022 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.0021 U Fluoranthene 0.0021 U 0.0022 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.0021 U Fluorene 0.0031 U 0.0032 U 0.0031 U 0.4 0.0031 U 0.0031 U 0.0031 U Indeno[1,2,3‐cd]pyrene 0.0072 U 0.0076 U 0.0073 U 0.0072 U 0.0071 U 0.0072 U 0.0072 U Naphthalene 0.03 J 0.025 J 0.025 J 17 0.013 U 0.013 U 0.13 Phenanthrene 0.021 U 0.022 U 0.021 U 0.53 0.0041 U 0.0041 U 0.021 U Pyrene 0.0041 U 0.0043 U 0.0042 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U

Page 14 of 44 Table G‐4 Groundwater Sample Results ‐ 7/8/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐070816 MW2‐070816 MW3‐070816 MW4‐070816 EW1‐070816DUP‐070816 EW2‐070816 Sample Date 7/8/16 10:30 7/8/16 11:10 7/8/16 11:55 7/8/16 13:00 7/8/16 14:05 7/8/16 12:00 7/8/16 15:10 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 9.2 J 0.027 U 0.027 U 0.034 J #2 Diesel (C10‐C24) 0.021 J 0.022 J 0.02 U 0.81 0.03 J 0.025 J 0.03 J Motor Oil (>C24‐C36) 0.071 J 0.16 J 0.05 J 0.029 U 0.11 J 0.073 J 0.03 U Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 15 of 44 Table G‐5 Groundwater Sample Results ‐ 7/15/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐071516 MW2‐071516 MW3‐071516 MW4‐071516 EW1‐071516 DUP‐071516 EW2‐071516 Sample Date 7/15/16 15:05 7/15/16 14:20 7/15/16 13:35 7/15/16 12:50 7/15/16 10:20 7/15/16 12:00 7/15/16 11:25 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 110 J 0.25 U 0.25 U 1J 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 170 J 0.27 U 0.27 U 1.3 J 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.17 J 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 54 0.26 U 0.26 U 0.35 J 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 6 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 900 0.42 U 0.42 U 1J Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.24 J 0.21 U

Page 16 of 44 Table G‐5 Groundwater Sample Results ‐ 7/15/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐071516 MW2‐071516 MW3‐071516 MW4‐071516 EW1‐071516 DUP‐071516 EW2‐071516 Sample Date 7/15/16 15:05 7/15/16 14:20 7/15/16 13:35 7/15/16 12:50 7/15/16 10:20 7/15/16 12:00 7/15/16 11:25 Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 100 J 0.21 U 0.21 U 0.66 J Hexachlorobutadiene ‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 25 0.3 U 0.3 U 0.3 U Isopropyltoluene ‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.6 J 500 0.3 U 0.3 U 2.3 J Naphthalene 0.26 U 0.26 U 0.26 U 25 0.26 U 0.26 U 0.35 J n‐Butylbenzene 0.3 U 0.3 U 0.3 U 28 0.3 U 0.3 U 0.3 U n‐Propylbenzene 0.13 U 0.13 U 0.13 U 22 0.13 U 0.13 U 0.16 J o‐Xylene 0.49 U 0.49 U 0.49 U 260 0.49 U 0.49 U 1.7 J sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 5.3 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.57 J 0.27 U 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 990 0.18 U 0.18 U 3.6 Total Xylenes ‐‐‐‐‐‐‐

Page 17 of 44 Table G‐5 Groundwater Sample Results ‐ 7/15/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐071516 MW2‐071516 MW3‐071516 MW4‐071516 EW1‐071516 DUP‐071516 EW2‐071516 Sample Date 7/15/16 15:05 7/15/16 14:20 7/15/16 13:35 7/15/16 12:50 7/15/16 10:20 7/15/16 12:00 7/15/16 11:25 trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0062 U 0.0061 U 0.0062 U 17 0.0062 U 0.0062 U 0.046 2‐Methylnaphthalene 0.0093 U 0.0091 U 0.0093 U 16 0.0093 U 0.0092 U 0.017 J Acenaphthene 0.0021 U 0.002 U 0.0021 U 0.072 0.0021 U 0.0021 U 0.0021 U Acenaphthylene 0.0021 U 0.002 U 0.0021 U 0.2 0.0021 U 0.0021 U 0.0021 U Anthracene 0.0031 U 0.003 U 0.0031 U 0.014 J 0.0031 U 0.0031 U 0.0031 U Benzo[a]anthracene 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.0021 U Benzo[a]pyrene 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[b]fluoranthene 0.0083 U 0.0081 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U Benzo[g,h,i]perylene 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[k]fluoranthene 0.0093 U 0.0091 U 0.0093 U 0.0092 U 0.0093 U 0.0092 U 0.0093 U Chrysene 0.0062 U 0.0061 U 0.0062 U 0.0061 U 0.0062 U 0.0062 U 0.0062 U Dibenz(a,h)anthracene 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.0021 U Fluoranthene 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.0021 U Fluorene 0.0031 U 0.003 U 0.0031 U 0.34 0.0031 U 0.0031 U 0.0031 U Indeno[1,2,3‐cd]pyrene 0.0072 U 0.0071 U 0.0072 U 0.0072 U 0.0072 U 0.0072 U 0.0072 U Naphthalene 0.013 U 0.017 J 0.015 J 14 0.013 U 0.013 U 0.061 Phenanthrene 0.0041 U 0.0068 J 0.0041 U 0.37 0.0041 U 0.0041 U 0.0041 U Pyrene 0.0041 U 0.004 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U

Page 18 of 44 Table G‐5 Groundwater Sample Results ‐ 7/15/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐071516 MW2‐071516 MW3‐071516 MW4‐071516 EW1‐071516 DUP‐071516 EW2‐071516 Sample Date 7/15/16 15:05 7/15/16 14:20 7/15/16 13:35 7/15/16 12:50 7/15/16 10:20 7/15/16 12:00 7/15/16 11:25 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 7J 0.027 U 0.027 U 0.039 J #2 Diesel (C10‐C24) 0.02 U 0.019 U 0.022 J 0.57 0.022 J 0.027 J 0.03 J Motor Oil (>C24‐C36) 0.03 U 0.029 U 0.03 U 0.045 J 0.03 U 0.089 J 0.03 U Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 19 of 44 Table G‐6 Groundwater Sample Results ‐ 7/20/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072016 MW2‐072016 MW3‐072016 MW4‐072016 EW1‐072016 EW2‐072016 Sample Date 7/20/16 15:10 7/20/16 14:30 7/20/16 13:40 7/20/16 12:50 7/20/16 10:30 7/20/16 11:30 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 95 43 4.5 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 170 40 4.3 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.18 J 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 46 16 1.4 J 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 5.4 1.3 J 0.26 U Benzene 0.42 U 0.42 U 0.42 U 790 280 12 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U

Page 20 of 44 Table G‐6 Groundwater Sample Results ‐ 7/20/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072016 MW2‐072016 MW3‐072016 MW4‐072016 EW1‐072016 EW2‐072016 Sample Date 7/20/16 15:10 7/20/16 14:30 7/20/16 13:40 7/20/16 12:50 7/20/16 10:30 7/20/16 11:30 Bromoform 0.23 J 0.21 U 0.21 U 0.21 U 0.25 J 0.27 J Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 97 26 2.1 J Hexachlorobutadiene ‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 21 4.2 0.45 J Isopropyltoluene ‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 470 120 8.3 Naphthalene 0.26 U 0.26 U 0.26 U 23 9.7 1.1 J n‐Butylbenzene 0.3 U 0.3 U 0.3 U 24 6.4 0.83 J n‐Propylbenzene 0.13 U 0.13 U 0.13 U 19 2.9 J 0.4 J o‐Xylene 0.49 U 0.49 U 0.49 U 240 100 8.5 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 4.7 0.75 J 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.89 J 0.68 J 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.42 J 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 820 290 16 Total Xylenes ‐‐‐‐‐‐

Page 21 of 44 Table G‐6 Groundwater Sample Results ‐ 7/20/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072016 MW2‐072016 MW3‐072016 MW4‐072016 EW1‐072016 EW2‐072016 Sample Date 7/20/16 15:10 7/20/16 14:30 7/20/16 13:40 7/20/16 12:50 7/20/16 10:30 7/20/16 11:30 trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0061 U 0.0062 U 0.0063 U 7.1 0.2 0.0078 J 2‐Methylnaphthalene 0.0092 U 0.0092 U 0.0095 U 1.6 0.0093 U 0.0096 U Acenaphthene 0.0048 J 0.0021 U 0.0021 U 0.064 0.0021 U 0.0021 U Acenaphthylene 0.002 U 0.0021 U 0.0021 U 0.09 0.015 J 0.0021 U Anthracene 0.0031 U 0.0031 U 0.0032 U 0.0031 U 0.0031 U 0.0032 U Benzo[a]anthracene 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U Benzo[a]pyrene 0.0031 U 0.0031 U 0.0032 U 0.0031 U 0.0031 U 0.0032 U Benzo[b]fluoranthene 0.0082 U 0.0082 U 0.0084 U 0.0082 U 0.0083 U 0.0086 U Benzo[g,h,i]perylene 0.0031 U 0.0031 U 0.0032 U 0.0031 U 0.0031 U 0.0032 U Benzo[k]fluoranthene 0.0092 U 0.0092 U 0.0095 U 0.0092 U 0.0093 U 0.0096 U Chrysene 0.0061 U 0.0062 U 0.0063 U 0.0062 U 0.0062 U 0.0064 U Dibenz(a,h)anthracene 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U Fluoranthene 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U Fluorene 0.0031 U 0.0031 U 0.0032 U 0.2 0.021 0.0032 U Indeno[1,2,3‐cd]pyrene 0.0072 U 0.0072 U 0.0074 U 0.0072 U 0.0073 U 0.0075 U Naphthalene 0.022 J 0.021 J 0.025 J 5.3 0.21 0.017 J Phenanthrene 0.0061 J 0.0075 J 0.0049 J 0.041 0.0044 J 0.0043 U Pyrene 0.0041 U 0.0041 U 0.0042 U 0.0041 U 0.0041 U 0.0043 U

Page 22 of 44 Table G‐6 Groundwater Sample Results ‐ 7/20/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072016 MW2‐072016 MW3‐072016 MW4‐072016 EW1‐072016 EW2‐072016 Sample Date 7/20/16 15:10 7/20/16 14:30 7/20/16 13:40 7/20/16 12:50 7/20/16 10:30 7/20/16 11:30 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 6.1 J 1.9 0.17 #2 Diesel (C10‐C24) 0.022 J 0.019 U 0.02 U 0.43 0.23 0.062 J Motor Oil (>C24‐C36) 0.03 U 0.03 U 0.26 U 0.03 U 0.055 J 0.032 U Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 23 of 44 Table G‐7 Groundwater Sample Results ‐ 7/27/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072716 MW2‐072716 MW3‐072716 MW4‐072716 EW1‐072716 EW2‐072716 FD‐072716 Sample Date 7/27/16 17:11 7/27/16 16:20 7/27/16 15:10 7/27/16 13:55 7/27/16 19:40 7/27/16 18:10 7/27/16 12:00 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.32 J 0.37 J 0.84 J 82 0.49 J 1.6 J 1.8 J 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.33 J 0.42 J 1.2 J 130 J 0.32 J 1.5 J 1.6 J 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 J 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.39 J 0.66 J 39 0.39 J 0.72 J 0.74 J 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 4.9 0.26 U 0.26 U 0.26 U Benzene 0.42 U 0.42 U 0.42 U 470 1.3 J 2 2 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.22 J 0.21 U 0.23 J 0.21 U

Page 24 of 44 Table G‐7 Groundwater Sample Results ‐ 7/27/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072716 MW2‐072716 MW3‐072716 MW4‐072716 EW1‐072716 EW2‐072716 FD‐072716 Sample Date 7/27/16 17:11 7/27/16 16:20 7/27/16 15:10 7/27/16 13:55 7/27/16 19:40 7/27/16 18:10 7/27/16 12:00 Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.33 J 70 0.21 U 0.83 J 0.92 J Hexachlorobutadiene ‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.37 J 0.43 J 16 0.3 U 0.47 J 0.49 J Isopropyltoluene ‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.93 J 250 J 0.3 U 2.6 J 2.9 J Naphthalene 0.26 U 0.35 J 0.93 J 15 0.33 J 0.56 J 0.57 J n‐Butylbenzene 0.3 U 0.3 U 0.53 J 24 0.3 U 0.42 J 0.43 J n‐Propylbenzene 0.19 J 0.23 J 0.34 J 16 0.19 J 0.3 J 0.29 J o‐Xylene 0.49 U 0.49 U 0.65 J 160 J 0.81 J 2.6 3 sec‐Butylbenzene 0.27 U 0.27 U 0.35 J 4.7 0.27 U 0.32 J 0.32 J Styrene 0.36 U 0.36 U 0.36 U 0.82 J 0.36 U 0.36 U 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.66 J 0.27 U 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 J 0.51 J 390 0.78 J 3.8 4.5 Total Xylenes ‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U

Page 25 of 44 Table G‐7 Groundwater Sample Results ‐ 7/27/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072716 MW2‐072716 MW3‐072716 MW4‐072716 EW1‐072716 EW2‐072716 FD‐072716 Sample Date 7/27/16 17:11 7/27/16 16:20 7/27/16 15:10 7/27/16 13:55 7/27/16 19:40 7/27/16 18:10 7/27/16 12:00 Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.016 J 0.012 J 0.012 J 1 0.0098 J 0.0099 J 0.0062 U 2‐Methylnaphthalene 0.032 0.027 J 0.026 J 0.062 0.025 J 0.022 J 0.015 J Acenaphthene 0.002 U 0.002 U 0.002 U 0.053 0.002 U 0.0021 U 0.0021 U Acenaphthylene 0.002 U 0.002 U 0.002 U 0.014 J 0.002 U 0.0021 U 0.0021 U Anthracene 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.0032 U 0.0031 U Benzo[a]anthracene 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.0021 U Benzo[a]pyrene 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.0032 U 0.0031 U Benzo[b]fluoranthene 0.0082 U 0.0081 U 0.0081 U 0.0084 U 0.0081 U 0.0086 U 0.0083 U Benzo[g,h,i]perylene 0.0031 U 0.003 U 0.003 U 0.0032 U 0.003 U 0.0032 U 0.0031 U Benzo[k]fluoranthene 0.0092 U 0.0091 U 0.0091 U 0.0095 U 0.0091 U 0.0096 U 0.0093 U Chrysene 0.0061 U 0.006 U 0.0061 U 0.0063 U 0.0061 U 0.0064 U 0.0062 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.0021 U Fluoranthene 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.0021 U Fluorene 0.0031 U 0.003 U 0.003 U 0.12 0.003 U 0.0032 U 0.0031 U Indeno[1,2,3‐cd]pyrene 0.0071 U 0.0071 U 0.0071 U 0.0074 U 0.0071 U 0.0075 U 0.0073 U Naphthalene 0.026 J 0.024 J 0.021 J 0.54 0.019 J 0.023 J 0.015 J Phenanthrene 0.0061 J 0.0065 J 0.0041 J 0.0042 U 0.004 U 0.0043 U 0.0042 U Pyrene 0.0041 U 0.004 U 0.0041 U 0.0042 U 0.004 U 0.0043 U 0.0042 U

Page 26 of 44 Table G‐7 Groundwater Sample Results ‐ 7/27/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐072716 MW2‐072716 MW3‐072716 MW4‐072716 EW1‐072716 EW2‐072716 FD‐072716 Sample Date 7/27/16 17:11 7/27/16 16:20 7/27/16 15:10 7/27/16 13:55 7/27/16 19:40 7/27/16 18:10 7/27/16 12:00 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 4.3 J 0.027 U 0.043 J 0.044 J #2 Diesel (C10‐C24) 0.019 U 0.11 U 0.11 U 0.31 0.11 U 0.25 0.11 J Motor Oil (>C24‐C36) 0.03 U 0.029 J 0.03 U 0.035 U 0.029 U 0.18 J 0.052 J Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 27 of 44 Table G‐8 Groundwater Sample Results ‐ 8/3/16 and 8/4/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐080416 MW2‐080416 MW3‐080416 MW4‐080316 MW5‐080316 MW6‐080316MW7‐080316 MW8‐080316 EW1‐080416 EW2‐080416 FD‐080416 Sample Date 8/4/16 12:15 8/4/16 11:30 8/4/16 10:40 8/3/16 12:15 8/3/16 13:55 8/3/16 14:53 8/3/16 16:45 8/3/16 17:45 8/4/16 13:25 8/4/16 14:20 8/4/16 12:00 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 75 0.83 J 0.37 J 0.25 U 0.25 U 2.41212 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 120 0.27 U 0.43 J 0.31 J 0.27 U 0.51 J 14 14 1,2‐Dibromo‐3‐Chloropropane1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U 1,2‐Dichloroethane 0.16 U 0.19 J 0.16 J 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 36 3U 3U 3U 0.26U 3U 4.2 4.2 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 4.7 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.49 J 0.5 J Benzene 0.42 U 0.42 U 0.42 U 840 0.42 U 0.42 U 0.42 U 0.42 U 6.33231 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 J 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U Chloroform 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U Dibromochloromethane 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 77 0.36 J 0.21 U 0.21 U 0.21 U 0.55 J 3.9 3.7 Hexachlorobutadiene ‐‐‐‐‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 17 0.42 J 0.37 J 0.3 U 0.3 U 0.41J 0.98J 1J Isopropyltoluene ‐‐‐‐‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U

Page 28 of 44 Table G‐8 Groundwater Sample Results ‐ 8/3/16 and 8/4/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐080416 MW2‐080416 MW3‐080416 MW4‐080316 MW5‐080316 MW6‐080316MW7‐080316 MW8‐080316 EW1‐080416 EW2‐080416 FD‐080416 Sample Date 8/4/16 12:15 8/4/16 11:30 8/4/16 10:40 8/3/16 12:15 8/3/16 13:55 8/3/16 14:53 8/3/16 16:45 8/3/16 17:45 8/4/16 13:25 8/4/16 14:20 8/4/16 12:00 m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 400 0.3 U 0.3 U 0.3 U 0.3 U 1.7 J 30 29 Naphthalene 0.26 U 0.26 U 0.26 U 19 2U 2U 2U 0.26U 2U 2U 2 n‐Butylbenzene 0.3 U 0.3 U 0.3 U 24 0.49 J 0.3 U 0.3 U 0.3 U 0.47J2.2J2.4J n‐Propylbenzene 0.13 U 0.13 U 0.13 U 14 3U 3U 0.13U 3U 0.13U 3U 3U o‐Xylene 0.49 U 0.49 U 0.49 U 190 0.49 U 0.49 U 0.49 U 0.49 U 5.32221 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 4.3 3U 0.27U 0.27U 0.27U 0.27U 3U 0.27U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.36 J 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 600 0.18 U 0.18 U 0.18 U 0.18 U 3.12624 Total Xylenes ‐‐‐‐‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0063 U 0.0061 U 0.006 U 0.41 0.0061 U 0.0061 U 0.0062 U 0.0062 U 0.0062 U 0.0063 U 0.0061 U 2‐Methylnaphthalene 0.0094 U 0.0092 U 0.009 U 0.064 0.0091 U 0.0092 U 0.0092 U 0.0092 U 0.0092 U 0.0094 U 0.0091 U Acenaphthene 0.0021 U 0.002 U 0.002 U 0.045 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.002 U Acenaphthylene 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.002 U Anthracene 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.003 U Benzo[a]anthracene 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.002 U Benzo[a]pyrene 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.003 U Benzo[b]fluoranthene 0.0083 U 0.0082 U 0.008 U 0.0081 U 0.0081 U 0.0081 U 0.0082 U 0.0082 U 0.0082 U 0.0083 U 0.0081 U Benzo[g,h,i]perylene 0.0031 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.003 U Benzo[k]fluoranthene 0.0094 U 0.0092 U 0.009 U 0.0091 U 0.0091 U 0.0092 U 0.0092 U 0.0092 U 0.0092 U 0.0094 U 0.0091 U Chrysene 0.0063 U 0.0061 U 0.006 U 0.0061 U 0.0061 U 0.0061 U 0.0062 U 0.0062 U 0.0062 U 0.0063 U 0.0061 U Dibenz(a,h)anthracene 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.002 U Fluoranthene 0.0021 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U 0.002 U Fluorene 0.0031 U 0.0031 U 0.003 U 0.055 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.003 U Indeno[1,2,3‐cd]pyrene 0.0073 U 0.0072 U 0.007 U 0.0071 U 0.0071 U 0.0071 U 0.0072 U 0.0072 U 0.0072 U 0.0073 U 0.0071 U Naphthalene 0.014 J 0.013 U 0.013 U 0.4 0.013 U 0.013 U 0.013 U 0.013 U 0.013 U 0.014 U 0.013 J Phenanthrene 0.0058 J 0.006 J 0.004 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0042 U 0.004 U Pyrene 0.0042 U 0.0041 U 0.004 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0042 U 0.004 U

Page 29 of 44 Table G‐8 Groundwater Sample Results ‐ 8/3/16 and 8/4/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐080416 MW2‐080416 MW3‐080416 MW4‐080316 MW5‐080316 MW6‐080316MW7‐080316 MW8‐080316 EW1‐080416 EW2‐080416 FD‐080416 Sample Date 8/4/16 12:15 8/4/16 11:30 8/4/16 10:40 8/3/16 12:15 8/3/16 13:55 8/3/16 14:53 8/3/16 16:45 8/3/16 17:45 8/4/16 13:25 8/4/16 14:20 8/4/16 12:00 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 5.3 0.027 U 0.027 U 0.027 U 0.027 U 0.045 J 0.44 0.37 #2 Diesel (C10‐C24) 0.11 U 0.11 U 0.11 U 0.48 0.11 U 0.12 U 0.11 U 0.11 U 0.11 U 0.22 J 0.11 U Motor Oil (>C24‐C36) 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.25 U 0.26 U 0.25 U Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 30 of 44 Table G‐9 Groundwater Sample Results ‐ 8/9/16 and 8/10/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐081016 MW2‐081016 MW3‐080916 MW4‐080916 MW5‐080916 MW6‐080916 MW7‐080916 MW8‐080916 EW1‐081016 DUP‐081016 EW2‐081016 Sample Date 8/10/16 10:45 8/10/16 10:00 8/9/16 15:15 8/9/16 12:30 8/9/16 11:00 8/9/16 11:40 8/9/16 13:25 8/9/16 14:20 8/10/16 11:50 8/10/16 11:00 8/10/16 13:00 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 73 2U 2U 0.25U 0.25U 15 15 4.3 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 99 3U 3U 0.27U 0.27U 13 12 4.9 1,2‐Dibromo‐3‐Chloropropane1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.17 J 0.16U 0.16U 1U 0.16U 0.16U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 34 3U 3U 0.26U 0.26U 5.4 5.1 3U 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 8 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 4.2 0.26 U 0.26 U 0.26 U 0.26 U 0.48 J 0.46 J 0.26 U Benzene 0.42 U 0.42 U 0.42 U 950 0.42 U 0.42 U 0.42 U 0.42 U 1309725 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U Bromoform 0.21 U 0.21 U 0.21 U 0.21 J 0.21 U 0.24 J 0.21 U 0.21 U 0.21 U 0.22 J 0.32 J Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U Chloroform 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U Dibromochloromethane 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 81 0.21 U 0.36 J 0.21 U 0.21 U 7.1 7 1.5 J Hexachlorobutadiene ‐‐‐‐‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 16 2U 2U 2U 2U 1.4 J 1.3 J 0.72 J Isopropyltoluene ‐‐‐‐‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U

Page 31 of 44 Table G‐9 Groundwater Sample Results ‐ 8/9/16 and 8/10/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐081016 MW2‐081016 MW3‐080916 MW4‐080916 MW5‐080916 MW6‐080916 MW7‐080916 MW8‐080916 EW1‐081016 DUP‐081016 EW2‐081016 Sample Date 8/10/16 10:45 8/10/16 10:00 8/9/16 15:15 8/9/16 12:30 8/9/16 11:00 8/9/16 11:40 8/9/16 13:25 8/9/16 14:20 8/10/16 11:50 8/10/16 11:00 8/10/16 13:00 m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 440 0.3 U 0.3 U 0.3 U 0.3 U 45 44 13 Naphthalene 0.26 U 0.26 U 0.26 U 20 2U 2U 0.26U 0.26U 32.6 2U n‐Butylbenzene 0.3 U 0.3 U 0.3 U 21 0.3 U 0.45 J 0.3 U 0.3 U 2.1J 2J 3U n‐Propylbenzene 0.13 U 0.13 U 0.13 U 13 3U 3U 0.13U 0.13U 3U 3U 3U o‐Xylene 0.49 U 0.49 U 0.49 U 240 0.49 U 0.49 U 0.49 U 0.49 U 44 42 10 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 3.9 3U 3U 0.27U 0.27U 0.27U 3U 3U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.69 J 0.7 J 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.38 J 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 640 0.18 J 0.18 U 0.18 U 0.18 U 98 94 11 Total Xylenes ‐‐‐‐‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0061 U 0.0062 U 0.057 8.2 0.0068 J 0.011 J 0.053 0.0061 U 0.44 J 0.022 J 0.0063 U 2‐Methylnaphthalene 0.0091 U 0.0094 U 0.14 2.3 0.017 J 0.025 J 0.024 J 0.011 J 0.069 J 0.0094 UJ 0.0094 U Acenaphthene 0.002 U 0.0021 U 0.02 J 0.093 0.022 0.0056 J 0.045 0.002 U 0.002 U 0.0021 U 0.0021 U Acenaphthylene 0.002 U 0.0021 U 0.03 0.11 0.047 0.0047 J 0.098 0.002 U 0.025 J 0.0021 UJ 0.0021 U Anthracene 0.003 U 0.0031 U 0.17 0.0094 J 0.13 0.0077 J 0.049 0.003 U 0.0087 J 0.0031 U 0.0031 U Benzo[a]anthracene 0.002 U 0.0021 U 0.84 0.0021 U 0.43 0.065 0.0021 U 0.002 U 0.057 J 0.0021 UJ 0.0021 U Benzo[a]pyrene 0.003 U 0.0031 U 0.79 0.0031 U 0.49 0.046 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.0031 U Benzo[b]fluoranthene 0.0081 U 0.0083 U 1 0.0083 U 0.64 0.079 0.0082 U 0.0081 U 0.0082 U 0.0084 U 0.0084 U Benzo[g,h,i]perylene 0.003 U 0.0031 U 1.2 0.0031 U 0.86 0.07 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.0031 U Benzo[k]fluoranthene 0.0091 U 0.0094 U 0.74 0.0093 U 0.45 0.07 0.0093 U 0.0091 U 0.0092 U 0.0094 U 0.0094 U Chrysene 0.0061 U 0.0062 U 0.7 0.0072 J 0.36 0.07 0.0062 U 0.0061 U 0.034 J 0.0063 UJ 0.0063 U Dibenz(a,h)anthracene 0.002 U 0.0021 U 1.2 0.0055 J 0.76 0.083 0.0021 U 0.002 U 0.002 U 0.0021 U 0.0021 U Fluoranthene 0.002 U 0.0062 J 0.7 0.0083 J 0.32 0.019 J 0.055 0.002 U 0.011 J 0.0021 U 0.0021 U Fluorene 0.003 U 0.0031 U 0.062 0.28 0.046 0.015 J 0.0031 U 0.0069 J 0.025 J 0.0031 UJ 0.0031 U Indeno[1,2,3‐cd]pyrene 0.0071 U 0.0073 U 1.3 0.0072 U 0.9 0.084 0.0072 U 0.0071 U 0.0071 U 0.0073 U 0.0073 U Naphthalene 0.014 J 0.016 J 0.15 6.7 0.041 U 0.013 U 0.041 U 0.013 U 0.58 J 0.053 J 0.014 U Phenanthrene 0.006 J 0.011 J 0.21 0.03 0.11 0.011 J 0.11 0.004 U 0.02 J 0.0042 UJ 0.0042 U Pyrene 0.0041 U 0.0061 J 0.64 0.018 J 0.31 0.018 J 0.021 0.004 U 0.013 J 0.0042 U 0.0042 U

Page 32 of 44 Table G‐9 Groundwater Sample Results ‐ 8/9/16 and 8/10/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐081016 MW2‐081016 MW3‐080916 MW4‐080916 MW5‐080916 MW6‐080916 MW7‐080916 MW8‐080916 EW1‐081016 DUP‐081016 EW2‐081016 Sample Date 8/10/16 10:45 8/10/16 10:00 8/9/16 15:15 8/9/16 12:30 8/9/16 11:00 8/9/16 11:40 8/9/16 13:25 8/9/16 14:20 8/10/16 11:50 8/10/16 11:00 8/10/16 13:00 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 5.3 J 0.027 U 0.027 U 0.027 U 0.027 U 0.87 0.77 0.12 #2 Diesel (C10‐C24) 0.11 U 0.11 U 0.12 U 0.44 0.12 U 0.11 U 0.12 U 0.11 U 0.21 U 0.23 U 0.11 U Motor Oil (>C24‐C36) 0.25 U 0.25 U 0.03 U 0.037 J 0.12 J 0.03 U 0.03 U 0.03 U 0.26 U 0.26 U 0.25 U Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 33 of 44 Table G‐10 Groundwater Sample Results ‐ 8/15/16 and 8/16/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐081516 MW‐2‐081516 MW3‐081616 MW4‐081616 MW5‐081616 MW6‐081616 MW7‐081616 MW8‐081616 EW1‐081616 DUP‐081616 EW‐2‐081516 Sample Date 8/15/16 13:00 8/15/16 13:40 8/16/16 15:30 8/16/16 13:30 8/16/16 13:00 8/16/16 12:20 8/16/16 11:40 8/16/16 11:00 8/16/16 17:00 8/16/16 12:00 8/15/16 12:10 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.34 J 0.3 J 0.87 J 74 0.25 U 0.25 U 0.25 U 0.25 U 30 30 9.7 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.37 J 0.27 U 0.27 U 120 0.27 U 0.27 U 0.27 U 0.27 U 32 31 11 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 1 U 0.16 U 0.16 U 1 U 0.16 U 0.16 U 1 U 0.16 U 0.16 U 1 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.37 J 0.34 J 3U 34 0.26 U 0.26 U 0.26 U 0.26 U 11 11 3.4 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.29 J 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 4.2 0.26 U 0.26 U 0.26 U 0.26 U 1 J 1 J 0.37 J Benzene 0.42 U 0.42 U 0.42 U 580 0.42 U 0.42 U 0.42 U 0.42 U 230 230 15 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.24 J 0.22 J 1 U 0.21 U 1 U 0.21 U 0.21 U 0.21 U 10 U 0.21 U 0.27 J Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.81 J 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.37 J 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 17 16 1.1 J Hexachlorobutadiene ‐‐‐‐‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 2 U 16 0.3 U 0.3 U 0.3 U 0.3 U 3 2.9 0.93 J Isopropyltoluene ‐‐‐‐‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U

Page 1 of 3 Table G‐10 Groundwater Sample Results ‐ 8/15/16 and 8/16/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐081516 MW‐2‐081516 MW3‐081616 MW4‐081616 MW5‐081616 MW6‐081616 MW7‐081616 MW8‐081616 EW1‐081616 DUP‐081616 EW‐2‐081516 Sample Date 8/15/16 13:00 8/15/16 13:40 8/16/16 15:30 8/16/16 13:30 8/16/16 13:00 8/16/16 12:20 8/16/16 11:40 8/16/16 11:00 8/16/16 17:00 8/16/16 12:00 8/15/16 12:10 m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 370 0.3 U 0.3 U 0.3 U 0.3 U 90 99 25 Naphthalene 2 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 0.26 U 6.4 7.1 2U n‐Butylbenzene 0.3 U 0.3 U 0.54 J21 0.3 U 0.3 U 0.3 U 0.3 U 5.1 5 1.4 J n‐Propylbenzene 3 U 3 U 3 U 13 3 U 0.13 U 0.13 U 3 U 1.7 J 1.7 J 3U o‐Xylene 0.49 U 0.49 U 0.49 U 180 0.49 U 0.49 U 0.49 U 0.49 U 84 82 18 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 3.8 0.27 U 0.27 U 0.27 U 3 U 3 U 3 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 1 J 1.1 J 0.45 J tert‐Butylbenzene 0.27 U 0.27 U 3 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 3 U 3 U 0.34 J Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 160 0.18 U 0.18 U 0.18 U 0.18 U 210 220 6.9 Total Xylenes ‐‐‐‐‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0062 U 0.0061 U 0.0061 U 5 0.0062 U 0.0062 U 0.0061 U 0.0063 U 2.3 1.9 0.0063 UJ 2‐Methylnaphthalene 0.0092 U 0.0092 U 0.0092 U 0.9 0.0093 U 0.0093 U 0.0092 U 0.0094 U 1.6 1.1 0.0094 UJ Acenaphthene 0.0021 U 0.002 U 0.002 U 0.079 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.017 J 0.015 J 0.0021 UJ Acenaphthylene 0.0021 U 0.002 U 0.002 U 0.079 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.083 0.07 0.0021 UJ Anthracene 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.0031 UJ Benzo[a]anthracene 0.0021 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.005 J Benzo[a]pyrene 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.0031 UJ Benzo[b]fluoranthene 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0084 U 0.0081 U 0.008 U 0.0083 UJ Benzo[g,h,i]perylene 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.003 U 0.003 U 0.0031 UJ Benzo[k]fluoranthene 0.0092 U 0.0092 U 0.0092 U 0.0092 U 0.0093 U 0.0093 U 0.0092 U 0.0094 U 0.0091 U 0.009 U 0.0094 UJ Chrysene 0.0062 U 0.0061 U 0.0061 U 0.0061 U 0.0062 U 0.0062 U 0.0061 U 0.0063 U 0.0061 U 0.006 U 0.0063 UJ Dibenz(a,h)anthracene 0.0021 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 UJ Fluoranthene 0.0021 U 0.002 U 0.002 U 0.002 U 0.0043 J 0.0021 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0059 J Fluorene 0.0031 U 0.0031 U 0.0031 U 0.18 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.054 0.049 0.0031 UJ Indeno[1,2,3‐cd]pyrene 0.0072 U 0.0071 U 0.0071 U 0.0071 U 0.0072 U 0.0072 U 0.0072 U 0.0073 U 0.0071 U 0.007 U 0.0073 UJ Naphthalene 0.013 U 0.013 U 0.013 U 3.2 0.013 U 0.013 U 0.013 U 0.014 U 2.6 2 0.014 UJ Phenanthrene 0.005 J 0.0041 U 0.0047 J 0.0041 U 0.0044 J 0.0041 U 0.0043 J 0.0042 U 0.027 0.022 0.0042 UJ Pyrene 0.0041 U 0.0041 U 0.0041 U 0.014 J 0.0074 J 0.0041 U 0.0041 U 0.0042 U 0.0068 J 0.0069 J 0.009 J

Page 2 of 3 Table G‐10 Groundwater Sample Results ‐ 8/15/16 and 8/16/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐081516 MW‐2‐081516 MW3‐081616 MW4‐081616 MW5‐081616 MW6‐081616 MW7‐081616 MW8‐081616 EW1‐081616 DUP‐081616 EW‐2‐081516 Sample Date 8/15/16 13:00 8/15/16 13:40 8/16/16 15:30 8/16/16 13:30 8/16/16 13:00 8/16/16 12:20 8/16/16 11:40 8/16/16 11:00 8/16/16 17:00 8/16/16 12:00 8/15/16 12:10 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 3.8 J 0.027 U 0.027 U 0.027 U 0.027 U 1.5 1.6 0.27 #2 Diesel (C10‐C24) 0.12 U 0.11 U 0.019 U 0.41 0.11 U 0.02 U 0.11 U 0.11 U 0.13 0.16 0.14 U Motor Oil (>C24‐C36) 0.057 J 0.03 U 0.029 U 0.03 U 0.03 U 0.03 U 0.03 U 0.26 U 0.26 U 0.26 U 0.13 J Natural Attenuation Parameters (mg/L) Alkalinity ‐‐69 140 120 100 89 85 70 71 ‐ Methane ‐‐0.0025 U 0.0025 U 0.0025 U 0.0025 U 0.0025 U 0.0025 U 0.0025 U 0.0025 U ‐ Nitrate as N ‐‐0.27 0.33 1.8 1.8 1.3 1.4 0.72 0.72 ‐ Nitrite as N ‐‐0.08 U 0.22 J 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U ‐ Sulfate ‐‐4.9 17 18 18 16 15 11 11 ‐ Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 3 of 3 Table G‐11 Groundwater Sample Results ‐ 8/23/16 and 8/24/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐082416 MW‐2‐082416 MW3‐082416 MW4‐082316 MW5‐082316 MW6‐082316 MW7‐082316 MW8‐082316 EW1‐082416 DUP‐082416 EW‐2‐082416 Sample Date 8/24/16 13:45 8/24/16 12:40 8/24/16 12:45 8/23/16 14:40 8/23/16 14:27 8/23/16 15:50 8/23/16 16:25 8/23/16 16:50 8/24/16 10:55 8/24/16 12:00 8/24/16 11:15 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 1.1 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.25 U 91 0.5 J 0.25 U 0.25 U 0.55 J 31 41 9.1 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1 U 0.23 U 1 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 160 0.27 U 0.27 U 0.27 U 0.93 J 26 37 12 1,2‐Dibromo‐3‐Chloropropane1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1 U 0.16 U 1 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 43 0.26 U 0.26 U 0.26 U 0.26 U 12 16 3.3 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 4.2 0.15 U 0.15 U 0.15 U 0.15 U 0.15 UJ 2.8 J 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 5 0.26 U 0.26 U 0.26 U 0.26 U 0.98 J 1.3 J 0.32 J Benzene 0.42 U 0.42 U 0.42 U 690 0.42 U 0.42 U 0.42 U 0.89 J 180 180 73 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U Bromoform 0.21 U 0.21 J 0.22 J 1 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 J 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U Chloroform 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U Dibromochloromethane 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 89 0.26 J 0.21 U 0.21 U 0.41 J 11 16 0.82 J Hexachlorobutadiene ‐‐‐‐‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 18 0.3 U 0.3 U 0.3 U 0.3 U 1.7J 2.6 0.74J Isopropyltoluene ‐‐‐‐‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U

Page 36 of 44 Table G‐11 Groundwater Sample Results ‐ 8/23/16 and 8/24/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐082416 MW‐2‐082416 MW3‐082416 MW4‐082316 MW5‐082316 MW6‐082316 MW7‐082316 MW8‐082316 EW1‐082416 DUP‐082416 EW‐2‐082416 Sample Date 8/24/16 13:45 8/24/16 12:40 8/24/16 12:45 8/23/16 14:40 8/23/16 14:27 8/23/16 15:50 8/23/16 16:25 8/23/16 16:50 8/24/16 10:55 8/24/16 12:00 8/24/16 11:15 m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 430 0.3 U 0.4 J 0.37 J 1.9 J 72 79 30 Naphthalene 0.26 U 0.26 U 2 U 18 2U 2U 0.26U 2U 4.8 6.4 2U n‐Butylbenzene 0.3 U 0.3 U 0.3 U 24 0.33 J 0.3 U 0.3 U 0.3 U 4.6 6.6 3U n‐Propylbenzene 0.13 U 0.13 U 0.13 U 16 0.13 U 0.13 U 0.13 U 0.13 U 1.3 J 1.9 J 0.27 J o‐Xylene 0.49 U 0.49 U 0.49 U 210 0.49 U 0.49 U 0.49 U 0.81 J 79 89 18 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.58 J 0.79 J 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 U 0.18 U 270 0.18 U 0.22 J 0.29 J 1.1 J 180 170 11 Total Xylenes ‐‐‐‐‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0061 U 0.0061 U 0.0061 U 3.5 0.0075 J 0.006 U 0.006 U 0.077 2.7 2.7 0.18 2‐Methylnaphthalene 0.0091 U 0.0092 U 0.0091 U 0.28 0.009 U 0.009 U 0.009 U 0.082 0.87 0.59 0.019 J Acenaphthene 0.002 U 0.002 U 0.002 U 0.065 0.002 U 0.002 U 0.002 U 0.002 U 0.043 J 0.028 J 0.0095 J Acenaphthylene 0.002 U 0.002 U 0.002 U 0.039 0.002 U 0.002 U 0.002 U 0.002 U 0.12 0.11 0.002 U Anthracene 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U Benzo[a]anthracene 0.002 U 0.0049 J 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Benzo[a]pyrene 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U Benzo[b]fluoranthene 0.0081 U 0.0082 U 0.0081 U 0.0081 U 0.008 U 0.008 U 0.008 U 0.008 U 0.0082 U 0.0081 U 0.0081 U Benzo[g,h,i]perylene 0.003 U 0.0031 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.003 U Benzo[k]fluoranthene 0.0091 U 0.0092 U 0.0091 U 0.0091 U 0.009 U 0.009 U 0.009 U 0.009 U 0.0092 U 0.0091 U 0.0091 U Chrysene 0.0061 U 0.0061 U 0.0061 U 0.0061 U 0.006 U 0.006 U 0.006 U 0.006 U 0.0061 U 0.0061 U 0.0061 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluoranthene 0.002 U 0.0046 J 0.002 U 0.0065 J 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U 0.002 U Fluorene 0.003 U 0.0031 U 0.003 U 0.14 0.003 U 0.003 U 0.003 U 0.003 U 0.072 0.067 0.003 U Indeno[1,2,3‐cd]pyrene 0.0071 U 0.0071 U 0.0071 U 0.0071 U 0.007 U 0.007 U 0.007 U 0.007 U 0.0071 U 0.0071 U 0.0071 U Naphthalene 0.013 U 0.013 U 0.013 U 2.1 0.014 J 0.016 J 0.015 J 0.061 3 2.7 0.11 Phenanthrene 0.0061 J 0.0081 J 0.0066 J 0.0041 U 0.004 U 0.0041 J 0.0048 J 0.0067 J 0.0088 J 0.0041 U 0.0041 U Pyrene 0.004 U 0.0043 J 0.0041 U 0.013 J 0.004 U 0.004 U 0.004 U 0.004 U 0.0041 U 0.0041 U 0.0041 U

Page 37 of 44 Table G‐11 Groundwater Sample Results ‐ 8/23/16 and 8/24/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐082416 MW‐2‐082416 MW3‐082416 MW4‐082316 MW5‐082316 MW6‐082316 MW7‐082316 MW8‐082316 EW1‐082416 DUP‐082416 EW‐2‐082416 Sample Date 8/24/16 13:45 8/24/16 12:40 8/24/16 12:45 8/23/16 14:40 8/23/16 14:27 8/23/16 15:50 8/23/16 16:25 8/23/16 16:50 8/24/16 10:55 8/24/16 12:00 8/24/16 11:15 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.027 U 4.2 0.027 U 0.027 U 0.027 U 0.05 U 1.4 1.5 0.3 #2 Diesel (C10‐C24) 0.11 U 0.11 U 0.11 U 0.5 0.11 U 0.11 U 0.11 U 0.11 U 0.31 0.28 0.12 Motor Oil (>C24‐C36) 0.03 U 0.09 J 0.029 U 0.03 U 0.029 U 0.029 U 0.029 U 0.029 U 0.029 U 0.048 J 0.045 J Natural Attenuation Parameters (mg/L) Alkalinity ‐‐‐‐‐‐‐‐‐‐‐ Methane ‐‐‐‐‐‐‐‐‐‐‐ Nitrate as N ‐‐‐‐‐‐‐‐‐‐‐ Nitrite as N ‐‐‐‐‐‐‐‐‐‐‐ Sulfate ‐‐‐‐‐‐‐‐‐‐‐ Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 38 of 44 Table G‐12 Groundwater Sample Results ‐ 9/1/16 and 9/2/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐090216 MW2‐090216 MW3 ‐ 090116 MW4 ‐ 090116 MW5 ‐ 090116 MW6 ‐ 090116 MW7 ‐ 090116 MW8 ‐ 090116 EW1‐090216 DUP‐090216 EW2‐090216 Sample Date 9/2/16 11:30 9/2/16 10:20 9/1/16 15:20 9/1/16 14:17 9/1/16 13:10 9/1/16 12:23 9/1/16 11:00 9/1/16 11:20 9/2/16 12:40 9/2/16 12:00 9/2/16 13:50 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U0.5U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.44 J 81 0.25 U 0.25 U 0.25 U 0.25 U 35 27 8.1 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 0.27 U 0.27 U 0.27 U 130 J 0.27 U 0.27 U 0.27 U 0.27 U 26 20 7.1 1,2‐Dibromo‐3‐Chloropropane1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U1.8U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 U 0.26 U 39 0.26 U 0.26 U 0.26 U 0.26 U 13 9.6 2.7 J 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U0.3U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 4.5 0.26 U 0.26 U 0.26 U 0.26 U 0.8J 0.6J 0.26 U Benzene 0.42 U 0.42 U 0.42 U 430 0.84 J 0.42 U 0.42 U 0.42 U 96 93 6.6 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U 0.3U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 1 U 0.21 U 1 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U 0.4U Chloroform 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U 0.5U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U0.2U Dibromochloromethane 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U 0.2U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 54 0.21 U 0.21 U 0.21 U 0.21 U 19 15 0.52 J Hexachlorobutadiene ‐‐‐‐‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 15 0.3 U 0.3 U 0.3 U 0.3 U 2.2 1.8 J 0.3 U Isopropyltoluene ‐‐‐‐‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U Methylene chloride 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U 1.3U

Page 39 of 44 Table G‐12 Groundwater Sample Results ‐ 9/1/16 and 9/2/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐090216 MW2‐090216 MW3 ‐ 090116 MW4 ‐ 090116 MW5 ‐ 090116 MW6 ‐ 090116 MW7 ‐ 090116 MW8 ‐ 090116 EW1‐090216 DUP‐090216 EW2‐090216 Sample Date 9/2/16 11:30 9/2/16 10:20 9/1/16 15:20 9/1/16 14:17 9/1/16 13:10 9/1/16 12:23 9/1/16 11:00 9/1/16 11:20 9/2/16 12:40 9/2/16 12:00 9/2/16 13:50 m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.3 U 250 0.3 U 0.3 U 0.3 U 0.3 U 91 71 9.2 Naphthalene 0.26 U 0.26 U 2 U 15 0.26U 0.26U 2U 2U 20U 20U 2U n‐Butylbenzene 0.3 U 0.3 U 0.34 J 21 0.3 U 0.3 U 0.3 U 0.3 U 4.4 3.2 1.3 J n‐Propylbenzene 0.13 U 0.13 U 0.13 U 12 0.13 U 0.13 U 0.13 U 0.13 U 1.1 J 0.88 J 0.18 J o‐Xylene 0.49 U 0.49 U 0.49 U 130 0.49 U 0.49 U 0.49 U 0.49 U 99 81 12 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.28 J 0.27 U 0.27 U Styrene 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.36 U 0.69 J 0.64 J 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 3.1 3.8 0.76 J 250 0.18 U 0.18 U 0.18 U 0.18 U 150 150 5.5 Total Xylenes ‐‐‐‐‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0061 U 0.006 U 0.006 U 5.5 J 0.0062 U 0.006 U 0.0061 U 0.0062 U 0.92 J 0.8 J 0.0062 U 2‐Methylnaphthalene 0.0092 U 0.009 U 0.009 U 1.3 J 0.0093 U 0.0091 U 0.0092 U 0.0093 U 0.13 J 0.087 J 0.0093 U Acenaphthene 0.002 U 0.002 U 0.002 U 0.067 J 0.0021 U 0.002 U 0.002 U 0.0021 U 0.013 J 0.014 J 0.0021 U Acenaphthylene 0.002 U 0.002 U 0.002 U 0.076 J 0.0021 U 0.002 U 0.002 U 0.0021 U 0.034 J 0.033 J 0.0021 U Anthracene 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[a]anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U Benzo[a]pyrene 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[b]fluoranthene 0.0081 U 0.008 U 0.008 U 0.0081 U 0.0083 U 0.008 U 0.0082 U 0.0083 U 0.0084 U 0.0082 U 0.0082 U Benzo[g,h,i]perylene 0.0031 U 0.003 U 0.003 U 0.003 U 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[k]fluoranthene 0.0092 U 0.009 U 0.009 U 0.0091 U 0.0093 U 0.0091 U 0.0092 U 0.0093 U 0.0094 U 0.0093 U 0.0093 U Chrysene 0.0061 U 0.006 U 0.006 U 0.0061 U 0.0062 U 0.006 U 0.0061 U 0.0062 U 0.0063 U 0.0062 U 0.0062 U Dibenz(a,h)anthracene 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U Fluoranthene 0.002 U 0.002 U 0.002 U 0.002 U 0.0021 U 0.002 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.0021 U Fluorene 0.0031 U 0.003 U 0.003 U 0.23 J 0.0031 U 0.003 U 0.0031 U 0.0031 U 0.023 J 0.025 J 0.0031 U Indeno[1,2,3‐cd]pyrene 0.0071 U 0.007 U 0.007 U 0.0071 U 0.0072 U 0.007 U 0.0072 U 0.0072 U 0.0073 U 0.0072 U 0.0072 U Naphthalene 0.013 U 0.013 U 0.013 U 3.8 J 0.013 U 0.013 U 0.013 U 0.013 U 1.2J 1.1J 0.013 U Phenanthrene 0.0058 J 0.0064 J 0.006 J 0.028 0.0058 J 0.004 U 0.0041 U 0.0041 U 0.0042 U 0.0041 U 0.0041 U Pyrene 0.0041 U 0.004 U 0.004 U 0.004 U 0.0041 U 0.004 U 0.0041 U 0.0041 U 0.0042 U 0.0065 J 0.0041 U

Page 40 of 44 Table G‐12 Groundwater Sample Results ‐ 9/1/16 and 9/2/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐090216 MW2‐090216 MW3 ‐ 090116 MW4 ‐ 090116 MW5 ‐ 090116 MW6 ‐ 090116 MW7 ‐ 090116 MW8 ‐ 090116 EW1‐090216 DUP‐090216 EW2‐090216 Sample Date 9/2/16 11:30 9/2/16 10:20 9/1/16 15:20 9/1/16 14:17 9/1/16 13:10 9/1/16 12:23 9/1/16 11:00 9/1/16 11:20 9/2/16 12:40 9/2/16 12:00 9/2/16 13:50 NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.029 J 3.4 0.027 U 0.027 U 0.027 U 0.027 U 1.3 1.4 0.18 #2 Diesel (C10‐C24) 0.11 U 0.11 U 0.11 U 0.46 0.11 U 0.11 U 0.11 U 0.12 U 0.2 U 0.21 U 0.18 U Motor Oil (>C24‐C36) 0.03 U 0.029 U 0.029 U 0.057 J 0.03 J 0.03 U 0.051 J 0.031 U 0.057 J 0.052 J 0.23 J Natural Attenuation Parameters (mg/L) Alkalinity ‐‐58 97 87 66 52 66 69 64 81 Methane ‐‐0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Nitrate as N ‐‐0.31 0.11 J 1.3 1.6 1 1.1 0.52 J 0.56 J 0.2 J Nitrite as N ‐‐0.08 U 0.08 U 0.08 U 0.08 U 0.08 U 0.08 U 0.08 R 0.08 R 0.08 R Sulfate ‐‐4.5161615111211J119.6 Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

Page 41 of 44 Table G‐13 Groundwater Sample Results ‐ 9/8/16 and 9/9/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐090916 MW2‐090816 MW3 ‐ 090816 MW4 ‐ 090816 MW5 ‐ 090816 MW6 ‐ 090816 MW7 ‐ 090816 MW8 ‐ 090816 EW1‐090916 DUP‐090916 EW2‐090916 Sample Date 9/9/16 13:50 9/8/16 16:00 9/8/16 10:50 9/8/16 11:40 9/8/16 12:25 9/8/16 13:05 9/8/16 14:00 9/8/16 15:20 9/9/16 11:10 9/9/16 10:00 9/9/16 12:40 Volatile Organic Compounds (µg/L) 1,1,1,2‐Tetrachloroethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 1,1,1‐Trichloroethane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,1,2,2‐Tetrachloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1,2‐Trichloroethane 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 0.24 U 1,1‐Dichloroethane 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,1‐Dichloroethene 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 1,1‐Dichloropropene 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 1,2,3‐Trichlorobenzene 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 1,2,3‐Trichloropropane 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 0.41 U 1,2,3‐Trimethylbenzene 0.25 U 0.25 U 0.29 J 83 0.25 U 0.25 U 0.25 U 0.25 U 58 55 10 1,2,4‐Trichlorobenzene 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 0.23 U 1,2,4‐Trimethylbenzene 3 U 0.34 J 0.76 J 150 0.27 U 0.27 U 0.27 U 0.27 U 56 52 12 1,2‐Dibromo‐3‐Chloropropane 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1.8 U 1,2‐Dibromoethane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,2‐Dichlorobenzene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 1,2‐Dichloroethane 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 J 0.16 U 0.16 J 0.16 U 0.16 U 0.16 J 1,2‐Dichloropropane 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 1,3,5‐Trimethylbenzene 0.26 U 0.26 J 0.35 J 40 0.26 U 0.26 U 0.26 U 0.26 U 22 21 4.4 1,3‐Dichlorobenzene 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 0.44 U 1,3‐Dichloropropane 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 0.15 U 1,4‐Dichlorobenzene 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 0.98 U 2,2‐Dichloropropane 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 0.32 U 2‐Chlorotoluene 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 4‐Chlorotoluene 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 0.28 U 4‐Isopropyltoluene 0.26 U 0.26 U 0.26 U 4.8 0.26 U 0.26 U 0.26 U 0.26 U 1.5 J 1.6 J 0.43 J Benzene 0.42 U 0.42 U 0.42 U 610 0.42 U 0.42 U 0.42 U 0.42 U 210 230 6.6 Bromobenzene 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Bromochloromethane 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U 0.29 U Bromodichloromethane 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U Bromoform 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U Bromomethane 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U 0.27 U Carbon tetrachloride 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U 0.55 U Chlorobenzene 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U 0.17 U Chloroethane 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U 0.4 U Chloroform 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Chloromethane 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U 0.64 U cis‐1,2‐Dichloroethene 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U 0.21 U cis‐1,3‐Dichloropropene 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromochloromethane 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U Dibromomethane 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U 0.34 U Dichlorodifluoromethane 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U 0.31 U Ethylbenzene 0.21 U 0.21 U 0.21 U 60 0.21 U 0.21 U 0.21 U 0.21 U 37 35 0.85 J Hexachlorobutadiene ‐‐‐‐‐‐‐‐‐‐‐ Hexachloro‐1,3‐butadiene 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U 0.49 U Isopropylbenzene 0.3 U 0.3 U 0.3 U 15 0.3 U 0.3 U 0.3 U 0.3 U 4.8 4.8 0.73 J Isopropyltoluene ‐‐‐‐‐‐‐‐‐‐‐ Methyl tert‐Butyl Ether (MTBE) 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U 0.11 U

Page 1 of 2 Table G‐13 Groundwater Sample Results ‐ 9/8/16 and 9/9/16 Union Pacific Railroad Company Mosier Release Site Assessment Report Sample ID MW1‐090916 MW2‐090816 MW3 ‐ 090816 MW4 ‐ 090816 MW5 ‐ 090816 MW6 ‐ 090816 MW7 ‐ 090816 MW8 ‐ 090816 EW1‐090916 DUP‐090916 EW2‐090916 Sample Date 9/9/16 13:50 9/8/16 16:00 9/8/16 10:50 9/8/16 11:40 9/8/16 12:25 9/8/16 13:05 9/8/16 14:00 9/8/16 15:20 9/9/16 11:10 9/9/16 10:00 9/9/16 12:40 Methylene chloride 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U 1.3 U m‐Xylene & p‐Xylene 0.3 U 0.3 U 0.53 J 230 0.3 U 0.3 U 0.3 U 0.3 U 140 160 9.1 Naphthalene 0.26 U 0.26 U 2 U 17 0.26 U 0.26 U 0.26 U 0.26 U 9.9 9.9 2U n‐Butylbenzene 0.3 U 0.3 U 0.51 J 22 0.3 U 0.3 U 0.3 U 0.3 U 0.3 U 7.6 2.5 J n‐Propylbenzene 0.13 U 0.13 U 0.13 U 12 0.13 U 0.13 U 0.13 U 0.13 U 3.4 3.1 0.26 J o‐Xylene 0.49 U 0.49 U 0.49 U 150 0.49 U 0.49 U 0.49 U 0.49 U 130 150 14 sec‐Butylbenzene 0.27 U 0.27 U 0.27 U 4 0.27 U 0.27 U 0.27 U 0.27 U 3 U 3 U 3 U Styrene 0.36 U 0.36 U 0.36 U 0.72 J 0.36 U 0.36 U 0.36 U 0.36 U 1.3 J 1.3 J 0.36 U tert‐Butylbenzene 0.27 U 0.27 U 0.27 U 0.51 J 0.27 U 0.27 U 0.27 U 0.27 U 0.42 J 0.34 J 0.27 U Tetrachloroethene (PCE) 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U 0.33 U Toluene 0.18 U 0.18 J 0.38 J 370 0.18 U 0.18 U 0.18 U 0.18 U 250 270 5.8 Total Xylenes ‐‐‐‐‐‐‐‐‐‐‐ trans‐1,2‐Dichloroethene 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U 0.71 U Trans‐1,3‐Dichloropropene 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U 0.16 U Trichloroethene (TCE) 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U 0.18 U Trichlorofluoromethane 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U 0.63 U Vinyl chloride 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U 0.22 U Semi‐Volatile Organic Compounds (µg/L) 1‐Methylnaphthalene 0.0062 U 0.0061 U 0.0062 U 13 0.0062 U 0.0061 U 0.0062 U 0.0061 U 2.6 1.8 0.036 2‐Methylnaphthalene 0.0094 U 0.0092 U 0.0093 U 8.6 0.0092 U 0.0092 U 0.0093 U 0.0092 U 0.59 0.42 0.0093 U Acenaphthene 0.0021 U 0.002 U 0.0021 U 0.1 0.0021 U 0.002 U 0.0021 U 0.002 U 0.024 0.02 0.0021 U Acenaphthylene 0.0021 U 0.002 U 0.0021 U 0.2 0.0021 U 0.002 U 0.0021 U 0.002 U 0.15 0.11 0.0021 U Anthracene 0.0031 U 0.0031 U 0.0031 U 0.0085 J 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[a]anthracene 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U Benzo[a]pyrene 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[b]fluoranthene 0.0083 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0082 U 0.0083 U 0.0082 U 0.0082 U 0.0082 U 0.0083 U Benzo[g,h,i]perylene 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.0031 U Benzo[k]fluoranthene 0.0094 U 0.0092 U 0.0093 U 0.0092 U 0.0092 U 0.0092 U 0.0093 U 0.0092 U 0.0092 U 0.0092 U 0.0093 U Chrysene 0.0062 U 0.0061 U 0.0062 U 0.0062 U 0.0062 U 0.0061 U 0.0062 U 0.0061 U 0.0062 U 0.0061 U 0.0062 U Dibenz(a,h)anthracene 0.0021 U 0.002 U 0.0021 U 0.0021 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U Fluoranthene 0.0021 U 0.002 U 0.0021 U 0.0071 J 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U 0.002 U 0.0021 U Fluorene 0.0031 U 0.0031 U 0.0031 U 0.39 0.0031 U 0.0031 U 0.0031 U 0.0031 U 0.093 0.087 0.0031 U Indeno[1,2,3‐cd]pyrene 0.0073 U 0.0071 U 0.0072 U 0.0072 U 0.0072 U 0.0071 U 0.0073 U 0.0071 U 0.0072 U 0.0071 U 0.0072 U Naphthalene 0.014 U 0.013 U 0.013 U 10 0.013 U 0.013 U 0.013 U 0.013 U 3.6 2.6 0.013 U Phenanthrene 0.0074 J 0.0041 U 0.0041 U 0.2 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0085 J 0.0041 U 0.0041 U Pyrene 0.0042 U 0.0041 U 0.0041 U 0.012 J 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U 0.0041 U NWTPH (mg/L) Gasoline 0.027 U 0.027 U 0.029 J 3.5 0.027 U 0.027 U 0.027 U 0.027 U 2.2 2.2 0.24 #2 Diesel (C10‐C24) 0.12 0.033 J 0.069 J 0.53 0.047 J 0.032 J 0.17 0.035 J 0.4 0.54 0.08 J Motor Oil (>C24‐C36) 0.058 J 0.03 U 0.18 J 0.035 J 0.05 J 0.03 U 0.043 J 0.03 U 0.079 J 0.087 J 0.03 U Notes: Results shown in bold denote detected concentrations. µg/L = microgram(s) per liter ID = identification MDL = method detection limit mg/L = milligram(s) per liter NWTPH = TPH by method Northwest TPH Qualifiers "‐" = Not analyzed * LCS or LCSD is outside acceptance limits. B = Compound was found in both the method blank and sample J = Result is less than the RL but greater than or equal to the MDL and the concentration is an approximate value U = Analyte was not detected above the MDL

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