Beneficial Ground Water Use Determination

Former Troh Landfill Property 10010 SE Vradenburg Road Happy Valley,

August 16, 2014

Prepared for: The Holt Group / Holt Homes 2601 NE 163rd Court Vancouver, 98684

Prepared by: Creekside Environmental Consulting, LLC 21790 Southwest Chehalis Court Tualatin, Oregon 97062 T. (503) 692-8118

and

P.O. Box 14488 Portland, Oregon 97293 T. 503-452-5561 E. [email protected]

LYNN D GREEN Exp. 1/31/2016

Contents 1.0 INTRODUCTION ...... 4 1.1 Background ...... 4 1.2 Purpose ...... 5 1.3 Scope ...... 5 2.0 SITE SETTING ...... 6 2.1 Description and Location ...... 6 2.2 Climate ...... 8 2.3 Topography ...... 9 2.4 Cultural Setting ...... 9 2.5 Regional Geologic Setting ...... 9 2.6 Site Geology ...... 10 2.7 ...... 10 2.7.1 Surface Water in the Vicinity of the Subject Property ...... 10 2.7.2 Ground Water ...... 10 2.7.3 Conceptual Hydrogeologic Model ...... 10 3.0 AREA OF STUDY ...... 11 4.0 WATER WELL RECORDS ...... 11 4.1 Oregon Water Resources Department (OWRD) GRID Database ...... 11 4.2 Door to Door Well Survey ...... 13 4.3 Sunrise Water Authority ...... 13 5.0 REVIEW OF OWRD’S WATER RIGHTS, PERMITS, AND CLAIMS ...... 13 5.1 Surface Water Rights ...... 14 5.2 Ground Water Rights ...... 14 6.0 DISCUSSION OF OTHER BENEFICIAL USES OF WATER ...... 14 7.0 CONCLUSIONS ...... 15 8.0 LIMITATIONS ...... 15

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Table (after text) 1 Water Wells in Area of Study

Figure (in text) 2-1 Historical 1967 Aerial Photograph of Troh's Nest Airfield 2-2 Happy Valley Climate Data

Figures (after text) 1 Site Vicinity Map 2 Site Plan 3 Zoning Map 4 Area of Study of Beneficial Water Use Determination 5 Sunrise Water Authority Service Area 6 Water Rights

Attachments A Water Well Logs

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Beneficial Ground Water Use Determination

Former Troh Landfill Property 10010 SE Vradenburg Road Happy Valley, Oregon 97086

1.0 INTRODUCTION At the request of The Holt Group / Holt Homes, Creekside Environmental Consulting, LLC (Creekside) has prepared this beneficial ground water use determination for ground water in the vicinity of 10010 SE Vradenburg Road, Happy Valley, Oregon (subject site; Figure 1). The site includes the former Troh Legacy Landfill facility, which was reportedly active between 1966 and 1971. Creekside requested EVREN Northwest, Inc. (ENW) to collaborate on the project. 1.1 Background The site was operated as the Troh Landfill from 1966 to 1971 and accepted construction and demolition wastes. A small abandoned airport hanger observed near the Troh Legacy Landfill and former air strip are remnants of the small private airport that formerly occupied the site. In 1971, CH2M Hill conducted a study of the landfill and concluded that the site was adequate for the (continued) operation of a demolition landfill, with enough soil cover to serve as a small sanitary landfill. CH2M Hill’s final recommendation to the Clackamas County Commissioners was to permit the site as a sanitary landfill operation in the future. Notwithstanding CH2M Hill’s study, the site was never permitted as a sanitary (municipal solid waste) landfill, and it was subsequently closed as a demolition and construction debris landfill. In 2004, Metro Government added the former Troh Legacy Landfill to its Legacy Landfill database. In 2011, Creekside conducted a preliminary investigation of the Troh Legacy Landfill concurrent with the Oregon Department of Environmental Quality's (ODEQ's) Preliminary Assessment (PA). Creekside observed that several acres had been used as a landfill. Debris consisting of old tires, scrap metal and wood, roofing, old drums, carpet scraps, automobile parts, and old appliances were present between five to ten feet below ground surface, and landfill leachate was draining from the southern tip of the landfill. For its PA, ODEQ prepared a Memorandum which summarized the results of the Troh Legacy Landfill site visit conducted by its technical staff members Ms. Miller and Mr. Fortuna on March 15, 2011. They observed landfilled debris that appeared to be disposed of relatively recently (i.e., between 1971 and present day) consisting of tires, metal, containers (metal, glass, plastic), old drums, demolition wastes (pavement, concrete, roofing, shingles, wood), carpet & foam padding, automotive items (car seats and enamel containers). Orange leachate was observed to be draining from the toe of the landfill to an ephemeral creek which discharges to Rock Creek (perennial stream), which has its confluence with Clackamas River at river mile 6.2.

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In their PA, ODEQ indicated that nearby construction or demolition projects at the time may have deposited wastes at the Troh Legacy Landfill; e.g., the adjacent Troh’s Nest airport serviced many small planes and may have dumped oils at the landfill. ODEQ also determined that other names for the landfill include the “Troh’s Nest”, and “Obrist & Chaney”. ODEQ stated that they “did not find any existing analytical data or documented contamination on the property”. Within Oregon Water Resources Department (OWRD) database, ODEQ identified 652 ground water wells within a 4-mile radius of the site, seven of which were domestic wells within one-half mile of the site. One of the seven domestic wells is an on-site well that serves the residential house on the same tax lot as the former landfill. Domestic wells in the landfill vicinity are 200 to 700 feet deep and pull water from the below the strata. Based on this information, ODEQ concluded that the landfill is not likely to contaminate local ground water wells, given the basalt layer is estimated to lie approximately 200 feet beneath the landfill. ODEQ concluded in the PA that further site investigation appeared warranted under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) on the basis of absence of analytical data, presence of leachate from landfill, pathway of leachate to potentially impact surface waters and on-site domestic drinking water well, and exposed wastes not completely covered with soil. In May 2014, Creekside conducted landfill characterization to delineate fill boundaries and depth, characterize the buried waste and investigate subsurface impacts with collection of representative soil samples at selected locations. Work also included collecting leachate water samples from two landfill cell seeps and soil gas samples from the periphery of landfill areas. 1.2 Purpose This beneficial ground water use determination evaluates the occurrence and beneficial use of ground water in the vicinity of the subject site, to support an assessment of potential risk to human and ecological receptors from residual impacts associated with the former landfill. 1.3 Scope The scope of this evaluation includes the following: Review of regional and site geology and hydrogeology and site zoning (site characterization). Development of a Conceptual Hydrogeologic Model and identification of an Area of Study. Review of available water well data, including a well log database search. Review of water rights and permits in the vicinity of the site. Identification of other beneficial uses of water in the vicinity of the site.

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2.0 SITE SETTING

2.1 Description and Location The subject property is located at 10010 SE Vradenburg Road, Happy Valley, Oregon (Figures 1 and 2). The site is irregular in outline and occupies a portion of the upper east flank of Scouters Mountain. The former Troh Legacy Landfill is centered near 45.4488°N, 122.4957°, within Township 1 South, Range 2 East (Willamette Meridian), Section 25D. Access is from SE Vradenburg Road along the west margin of the property. An abandoned airport hangar is located on the northern portion of the property, and former crossing air strips run the length of the site from south to north and southwest to northeast. These features are remnants of the former Troh’s Nest Airport (see 1967 photograph below). These former air strips are now used as local roads to access the three residences at the site. SE Airport Road is a former air strip that is accessed from a gated drive off of SE Vradenburg Road, and it provides access to a single-family residence to the south (on Tax Lot 401). At is north end, SE Airport Road connects to two other roads that were once air strips or cross-connecting taxi-ways. These roads access a single-family residence on the northeast part of the site (on Tax Lot 401) and a single-family residence on the east part of the site (on Tax Lot 1801). The Troh Legacy Landfill (identified as the 'North Cell' on Figure 2) is located on the east side of Tax Lot 401 and covers an area of approximately 1.5 acres. Evidence of land clearing and construction of a benched fill was observed within an approximately 7-acre area on the southern part of the site (on Tax Lots 400, 1800, and 1801). Little or no solid waste was observed in this area. Beyond the residences noted above, the site is currently wooded and covered with thick undergrowth, with the exception of some grassy meadows and wetlands along the east side of SE Airport Road. A power line cuts through the easternmost portion of the property.

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Figure 2-1. Historical 1967 Aerial Photograph of Troh's Nest Airfield Source: http://www.airfields-freeman.com/OR/Airfields_OR_NW.htm#happyvalley

A 1967 aerial photo looking west at Troh’s Nest airfield with the 2nd longer runway completed (courtesy of Viola Troh Gabel via Jonathan Westerling). Henry Troh’s house is in the foreground, and dozens of light planes were on the field. The Troh Legacy Landfill is visible in the bottom part of the photograph.

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2.2 Climate Happy Valley, Oregon has a temperate climate with dry warm summers and wet mild winters. Spring and fall are transitional seasons. The majority of Happy Valley's annual precipitation falls between November and February. Severe cold snaps, although rare, can last for several days. The following graphs summarize Happy Valley climate data.

Figure 2-2. Happy Valley Climate Data Source http://www.city-data.com/city/Happy-Valley-Oregon.html

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2.3 Topography The subject site is located within the US Geological Survey Damascus, Oregon 7.5-minute quadrangle, between approximate 575 and 800 feet elevation above mean sea level (Figure 1). The site occupies an elevated topographic "bench" and east slope of Scouters Mountain, in the highland area between the Portland Basin and the Clackamas River. The site slopes variably to the east. 2.4 Cultural Setting A zoning map is presented in Figure 3. The site is zoned Residential 15,000 and 20,000 square feet lot minimum" by the City of Happy Valley's Final Zoning Map dated 2012. It is the intention of the property owners to redevelop the property as a multi-residential development. Therefore the site will undergo a construction phase followed by residential use. Properties to the north, east, south, and west are similarly zoned; however, a Boy Scout camp is mapped to the west, at the crest of Scouters Mountain. We have noted that the Clackamas County zoning map dated 2012 shows the vicinity of the property as Rural Residential Farm Forest (RRFF-5), but that map as well as Clackamas County's CMAP online GIS application appear to indicate that zoning of incorporated cities overrides the county's zoning map. 2.5 Regional Geologic Setting The site is located in the volcanic highlands between the Portland Basin and the Clackamas River, generally known as the Boring Field.1 The area is characterized by young (Pleistocene) volcanic cones and basalt flows composed of basalt or , mapped collectively as Boring . The valleys and lowlands between and bounding the volcanic highlands are occupied by small creeks, and are underlain by the Springwater Formation (? to Pleistocene) and older Troutdale Formation (Miocene-Pliocene). The Springwater Formation is composed of fluvial sediments originating from the Cascades Mountain highlands to the east. The Troutdale Formation is considered to be the ancestral deposits of the Columbia River and its coeval Cascadian sediments. Boring Lavas are generally resistant to erosion and protect underlying rocks from erosion, thus accounting for their occurrence as highlands and cones greatly dissected and modified by fluvial processes.

1 Madin, I.P., 1994, Geologic Map of the Damascus Quadrangle, Clackamas and Multnomah Counties, Oregon: State of Oregon Department of Geology and Mineral Industries, Geological Map Series GMS-60, Map 1:24,000.

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2.6 Site Geology Madin1 mapped the Boring Lava below the site as belonging to the Basalt of Mt. Scott flow unit. The source of the flow is not known but is suspected to be vented to the north or northeast of the site. The flow is believed to be up to 260 feet thick. Locally fill and waste debris have been placed in cleared and cut areas on the subject site. Creekside's borings onsite have shown waste debris in excess of 12 feet thickness at the Former Troh Legacy Landfill location ('North Cell'). 2.7 Hydrogeology 2.7.1 Surface Water in the Vicinity of the Subject Property Perennial and ephemeral (intermittent) streams originate on the site and flow through and off the site through channeled ravines, predominantly on the east side of the site, eventually discharging to Rock Creek, located approximately 1 mile south and east of the site. A wetland consisting of marshy ground and wetland grasses was identified at the western part of the site. An area of ponding at the southwest corner of the North Cell was observed during 2014 field work. Ground water seeps to the surface were identified proximate to the North and South Cells.

2.7.2 Ground Water Localized perched water bodies can occur within or above the Boring Lavas (e.g., within scoriaceous flow-top ), the saturated thickness of which depends on the structure and of the rocks, topographic position, and extent of surficial . Ground water movement will follow topography and is expected to migrate to the east and south towards Rock Creek. Water wells in the upper elevations of Scouter Mountain are typically completed in the sedimentary formations (Springwater and Troutdale Formations) underlying the Boring Lavas. Ground water in the Springwater and Troutdale Formation probably discharges to the Clackamas River and its tributaries (including Rock Creek). Occurrence of ground water is further discussed in Section 4.1.

2.7.3 Conceptual Hydrogeologic Model The subject property is located in a topographically highland area on Scouter Mountain. All water originates as precipitation at this location. Precipitation either 1) infiltrates into the ground, 2) runs off to nearby small ephemeral and perennial creeks, 3) evaporates, or 4) becomes biologic uptake and returns to the atmosphere by transpiration. Shallow (perched) ground water generally discharges to Rock Creek, where it flows to the southwest to the Clackamas River. Deeper ground water in the Springwater and Troutdale Formations probably discharges to the Clackamas River and its tributaries (including Rock Creek), as noted above. In addition, small volumes of

CEC/ENW 10 August 16, 2014 Project No. THG-2014.3 / 351-14002-02 Former Troh Landfill Property Beneficial Ground Water Happy Valley, OR Use Determination ground water are withdrawn by domestic water wells. All the water wells reviewed for this survey were listed as domestic use.

3.0 AREA OF STUDY The Locality of the Facility (LOF) is defined as any point where a human or an ecological receptor is reasonably likely to come into contact with facility-related hazardous substances. The LOF takes into account the likelihood of the contamination migrating over time and may be larger than the facility. This beneficial ground water use determination identified a conservative Area of Study. The development of the boundaries of this Area of Study is described below and is based on ground water flow and hydrogeologic boundaries (see Figure 4). This Area of Study will be further refined during the site Risk Assessment by including an assessment of fate and transport of COPCs as well as presence of receptors.

North: The northern boundary of the Area of Study was chosen as SE Maple Hill Road, extending westward to the west side of SE Vradenburg Road. SE Maple Hill Road winds its way up the east side of Scouters Mountain and has many homes with water wells. The northern boundary also includes the northern portion of the topographic bench north of the landfill cells. This boundary should be cross-gradient to any surface water or ground water flow from the property.

West: SE Vradenburg Road and the adjacent relatively flat topographic "bench" was chosen as the western boundary since it is the topographic high side of the property, and higher elevations are present to the west (the summit of Scouter Mountain). Predominant drainage is to the east.

South: The southern boundary of the Area of Study was chosen as just north of John Hagen Road. This boundary should be cross-gradient to any surface water or ground water flow from the property.

East: Properties to the east of the subject site are hydrogeologically down-gradient. We arbitrarily chose SE 172nd Avenue as the east margin of the Area of Study.

4.0 WATER WELL RECORDS

4.1 Oregon Water Resources Department (OWRD) GRID Database The OWRD maintains the GRID (Ground water Information Database) consisting of logs for borings and wells in the State. The following should be noted with regard to the logs within the database: 1. Over the years the well report form has changed several times, and the filing of well logs has only been required since 1955;

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2. Older wells are frequently undocumented; 3. Well logs are completed and filed by well drillers and well locations are commonly poorly described; 4. Older wells have the names of the original property owners which are not updated with changes of title; 5. Drillers also have no training in materials descriptions, and their described in the well logs should be considered carefully during review. Therefore, this beneficial use survey is conservative in considering database-listed water wells, as discussed below.

Well Identification. The site is located in the southwest quarter of the southwest quadrant of Section 25, Township 1 South, Range 2 East of the Willamette Meridian. Therefore, as a starting point, the OWRD GRID well log review conducted for this report included inspection of all water well logs for Sections 25 and 36, Township 1 South, Range 2 East and for Sections 30 and 31 of Township 1S, Range 3 East. Note that this is very conservative in that the listed Sections extend far outside the identified Area of Study. Therefore the well logs were additionally screened for location as follows: All wells located west of SE Vradenburg Road addresses were screened out, since these addresses are across a topographic divide and are unlikely to be impacted by the release from the subject property. Similarly, all addresses on SE Vradenburg Road, SE Maple Hill Lane, SE 162nd Avenue, and SE 172nd Avenue's odd numbered addresses were retained within the limits of the north and south boundaries of the Area of Study. All water well logs passing the initial screen described above were further screened to eliminate from consideration those logs that were determined to be inappropriate to the discussion of beneficial uses of ground water in the vicinity of the subject property. Since there are no beneficial uses associated with decommissioned water wells, geotechnical borings, monitoring wells, piezometers, cathodic protection wells, or injection wells, these well/boring types were screened out. Dewatering wells were also screened out, since they do not have beneficial use. Many wells did not have adequate locations to accurately locate. These wells are not included in the table, since the residential density in the vicinity of the subject property is low, and enough water wells were identified within the Area of Study to characterize ground water occurrence and use. Table 1 (located after text) summarizes the well logs retained for evaluation. The water wells listed in Table 1 were further reviewed for completion depth, aquifer type and communication with the impacted aquifer, depth of perforations/screens, applied use, presence or absence of low

CEC/ENW 12 August 16, 2014 Project No. THG-2014.3 / 351-14002-02 Former Troh Landfill Property Beneficial Ground Water Happy Valley, OR Use Determination permeability zones above the producing zones. Referenced well logs are included in Attachment A.

Findings. Logs of wells completed in the site's vicinity indicated that water wells were completed at depths ranging from 278 to 800 feet below ground surface. Static water levels ranged from 60 feet (in water well log Clac #219 for the well at 16900 Maple Hill Lane at a topographically low elevation on the hillside) to 586 feet below ground surface. Other than the 16900 Maple Hill Lane address, all other static water levels exceeded 100 feet below ground surface. The yield of the wells was generally low (equal to or less than 10 gallons per minute for those located in topographically higher locations on Scouter Mountain) to 60 gallons per minute for lower elevation wells completed in Springwater/Troutdale Formation . Review of the well logs for locations along the crest of Vrandenburg Road indicate that those wells are completed through the into the underlying sedimentary aquifers, from which they produce potable water. Oregon water well regulations require a minimum surface casing depth of 18 feet, and water well drillers on Scouters Mountain in the vicinity of the former Troh Landfill would advance their surface casing to seal off unconsolidated soils and any perched water above competent (i.e., unweathered) bedrock. The construction, depth of the producing zones of the wells, and aquifers from which they produce indicate that the landfill is unlikely to impact the beneficial uses of the wells within the Area of Study. 4.2 Door to Door Well Survey Since development in the vicinity of the former Troh Landfill was begun after Oregon water well regulations requiring start cards and filing of well logs were implemented, and since the OWRD's GRID database appears to be adequate for review of water wells in the vicinity, a door-to door survey was not performed. 4.3 Sunrise Water Authority According to Clackamas County, the water purveyor for the vicinity of the site is the Sunrise Water Authority. The Sunrise Water Authority's web site provides a map of its service area (see Figure 5), which includes the former Troh Landfill. The planned residential development of the property by the current property owner will entail connection to the Sunrise Water Authority water system. Sunrise Water Authority obtains water from the Clackamas River through three different agencies; the North Clackamas County Water Commission, the Clackamas River Water District, and the South Fork Water Board. It also maintains several water wells for emergency and seasonal use, as well as wells listed as inactive.

5.0 REVIEW OF OWRD’S WATER RIGHTS, PERMITS, AND CLAIMS The waters of Oregon collectively belong to the public and cannot be owned by any one individual or group. Instead, individuals or groups may be granted rights to use them. A water right is a legal authorization to use a predefined quantity of public water for a designated purpose. Any

CEC/ENW 13 August 16, 2014 Project No. THG-2014.3 / 351-14002-02 Former Troh Landfill Property Beneficial Ground Water Happy Valley, OR Use Determination use of surface water (e.g., lakes, ponds, rivers, streams, or springs) and any use of ground water requires a water-right permit or certificate. ENW accessed OWRD's Water Rights Database and Mapping Tool to research water rights, permits, and claims in the vicinity of the subject property. 5.1 Surface Water Rights There were no surface water rights (i.e., points of diversion) in the Area of Study, as determined by interactive mapping on the OWRD web site (Figure 6). 5.2 Ground Water Rights Oregon Water Law exempts the following ground water uses from permitting and water rights regulations: 1. Stock watering. 2. Lawn or noncommercial garden: watering of not more than one-half acre in area. 3. Single or group domestic purposes: not exceeding 15,000 gallons per day. 4. Single industrial or commercial purposes: not exceeding 5,000 gallons per day. 5. Down-hole heat exchange uses. 6. Watering school grounds: ten acres or less, of schools located within a critical ground water area. Figure 6 indicates all ground water rights points of diversion (i.e., water wells) in the vicinity of the subject property. The closest ground water right is outside of the Area of Study. No other ground water points of diversion were identified within the vicinity of the subject property. The water rights review therefore indicates nonexempt beneficial uses of ground water in the vicinity of the site are unlikely to be impacted by the former Troh Landfill.

6.0 DISCUSSION OF OTHER BENEFICIAL USES OF WATER Wildlife (Ecological). Leachate is flowing from the lobes of the landfill to nearby hillside creeks and then flowing down the hillside. The Mt. Scouter creeks are too steep to permit aquatic life but may provide water to nonaquatic wildlife species. The eventual down-slope discharge is to Rock Creek.

Geothermal Heating and Cooling. Ground water may be used as a geothermal heating and cooling resource. No reviewed well logs or water rights indicated/suggested use of ground water for geothermal heating and cooling; however, these beneficial uses should not be impacted by the landfill impacts since ground water is so deep and geothermal use is non-consumptive.

Surficial Vegetation. The depth to trapped water within the landfill mass is generally less than 15 feet, based on Creekside's previous environmental investigations at the site. Although direct uptake by deep-rooted vegetation in the vicinity of the subject property is possible, no visible impacts were observed to vegetation.

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Recreation and Aesthetics. There are no current recreational and aesthetic resources in the vicinity of the property that would be affected by the residual impacts at the subject site. Anticipated residential redevelopment of the site should address future recreational and aesthetic qualities.

7.0 CONCLUSIONS Creekside/ENW first developed a Conceptual Hydrogeologic Model for the subject site and then evaluated beneficial water use in a conservative Area of Study that was developed based on major topographic and geological constrains. A review of OWRD water well and water rights databases and other data showed: The landfill property is located on a relatively high topographic "bench" on Scouter Mountain. Population density is low in this area, but increases near the eastern base of the mountain where topographic gradient decreases at the margin of Pleasant Valley. Perched (trapped) water within the landfill mass, if present, it at less than 15 feet below ground surface; however, is not used for drinking water. All existing water wells are completed in bedrock aquifers and are therefore unlikely to be affected by the impacts to the soils and perched ground water above bedrock. Water wells in the Area of Study are deep and almost all produce water from the sedimentary bedrock aquifers of the Springwater and/or Troutdale Formations, stratigraphically beneath the Boring Lavas (Basalt of Mt. Scott flow unit) that comprise the upper portion of Scouter Mountain. There are many water wells indicated in the Area of Study of this Beneficial Water Use Determination. However, the Sunrise Water Authority has provided water service into the vicinity of the subject property, and it is likely that all future development in the vicinity will connect to the water system. No surface or ground water rights points of diversion were identified in the Area of Study.

8.0 LIMITATIONS The scope of this report is limited to observations made during on-site work, interviews with knowledgeable sources, and review of readily available published and unpublished reports and literature. As a result, these conclusions are based on information supplied by others as well as interpretations by qualified parties. The focus of this survey does not extend to the presence of the following conditions unless they were the express concerns of contacted personnel, report and literature authors or the work scope. Naturally-occurring toxic or hazardous substances in the subsurface soils, geology and water.

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Toxicity of substances common in current habitable environments, such as stored chemicals, products, building materials and consumables, Contaminants or contaminant concentrations that are not a concern now but may be under future regulatory standards. Unpredictable events that may occur after our site visit, such as illegal dumping or accidental spillage. Creekside and ENW have performed services for this project in accordance with our agreement and understanding with the Client. This document and the information contained herein have been prepared solely for the use of the Client. Creekside and ENW performed this study under a limited scope of services, per agreement. It is possible, despite the use of reasonable care and interpretation, that we may have failed to identify regulation violations related to the presence of hazardous substances other than those specifically mentioned at the closure site. We assume no responsibility for conditions that we did not specifically evaluate or conditions that were not generally recognized as environmentally unacceptable at the time this report was prepared.

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TABLE

Table 1. Water Wells in Area of Study [Source: Selected Well Logs from Oregon Water Resources Resource Information Database (GRID)]

Well Quarter‐ post static county Well township range Quarter Quarter type of depth depth completed water code Number township char range char Section Section Section Tax Lot Street of Well Name Last Name Company Street zip log first water drilled depth level work new use domestic max yield Section 25, Township 1 South, Range 2 East CLAC 329 1 S 2 E 25 SE SE TRON 9700 SE 162ND 97236 W 540 540 503 X X 10 CLAC 327 1 S 2 E 25 9901 SE Vrandenberg Rd. MOFFITT MOFFITT, GALE K 9901 SE VRANDENBURG RD 97236 W 193 278 270 170 X X 7 CLAC 324 1 S 2 E 25 NW NE 9595 VRANDENBERG RD PORTLAND MOFFITT 9595 SE VRANDENBERG RD 97236 W 358 395 395 347 X X 2 CLAC 322 1 S 2 E 25 SE NE 9700 SE 162nd Avenue COX PO BOX 431 97030 W 595 625 625 584 X 6 CLAC 50746 1 S 2 E 25 SE NE 100 9600 SE VRADENBURG RD NELSON NELSON, DALENE 16822 SE POWELL BLVD 100 97236‐1791 W 622 622 X X CLAC 51500 1 S 2 E 25 SE NE 100 9600 SE VRADENBURG RD NELSON NELSON, DALENE 16822 SE POWELL BLVD 100 97236‐1791 W 610 610 X X CLAC 51598 1 S 2 E 25 SE NE 103 9600 SE VANDENBURG NELSON 16822 SE POWELL BLVD 100 97236‐1791 W 630 800 700 586 X 5

Section 36, Township 1 South, Range 2 East [None identified]

Section 30, Township 1 South, Range 3 East CLAC 635 1 S 3 E 30 16450 SE Maple Hill Lane ENGSTROM ENGSTROM, MRS LYNN B 16450 SE MAPLE HILL LANE 97009 W 358 354 300 X 20 CLAC 634 1 S 3 E 30 SW SW 10150 SE Vrandenburg Rd FERRY 10150 SE VRANDENBURG RD 97236 W 300 370 370 250 X X 4 CLAC 631 1 S 3 E 30 9905 SE 172ND AVE STEVENS 9905 SE 172ND AVE 97009 W 200 240 225 140 X X 20 CLAC 186 1 S 3 E 30 SW NE 201 CHASE 17020 SE MAPLE HILL LANE 97009 W 240 330 310 155 X 20 CLAC 219 1 S 3 E 30 16900 MAPLE HILL LN BORING MOHN 16900 MAPLE HILL LANE 97009 W 260 330 305 60 X 20 CLAC 1540 1 S 3 E 30 SW SW 2100 10159 SE 172ND UTBERG 10159 SE 172ND 97009 W 280 325 325 200 X X 25 CLAC 18610 1 S 3 E 30 1501 16321 SE MAPLE HILL LN BORING COLES 16321 SE MAPLE HILL LANE 97009 W 460 520 475 367 X X 20 CLAC 12311 1 S 3 E 30 SE SW 800 16859 SE MAPLE HILL LANE LAMORILLE 21135 NE INTERLACHEN LANE 97060 W 285 385 370 290 X X 25 CLAC 53703 1 S 3 E 30 SW SE 2700 10473 SE 172ND KARAM 10473 SE 172ND 97009 W 240 340 340 130 X X 60 CLAC 58059 1 S 3 E 30 SW NE 202 17032 SE MAPLE HILL LANE CHASE 17032 SE MAPLE HILL LANE 97009 W 360 360 360 144 X X 60 CLAC 59103 1 S 3 E 30 SW SW 1500 NEXT TO 16321 SE MAPLE HILL LANE, BORINJOHNSON 645 NE 26TH ST 97030 W 460 580 580 399 X X 25 CLAC 68977 1 S 3 E 30 SW NE 300 9747 SE 172ND AVE HAPPY VALLEY OR 97086 NEW LIFE MISSIONARY CHURCH 6220 SE 92ND AVE 97266 W 271 343 343 211.5 X X 35

Section 36, Township 1 South, Range 3 East [None identified]

well_logs.xlsxTable 1 well_logs Creekside Environmental Consulting / EVREN Northwest 8/7/2014 P:\351(Creekside_Environmental)\2014\14002(Troh_Landfill)\02(RA_CMMP)\benuse\water wells\well_logs.xlsx

FIGURES

Project No. Date Drawn: 8/13/2014 Troh Landfill 351-14002-02 CAD File Name: 351-14002fig1sv_map(v03) Drawn By: KMC 45º 26’ 57.59”N / 122º 29’ 49.78” W Figure No. Approved By: BJ Site Vicinity Map Happy Valley, Oregon 1

TL400 TL401 TL1600

NORTH CELL TL1700

TL1800

SOUTH CELL TL1801 SURFACE TL1802 DUMP FORMER CLEARED AREA SITE SE VRADENBURG ROAD SE VRADENBURG AIRPORT ROAD AIRPORT TL1800

BENCHED FILL AREA

0 250 500

CREEKSIDE ENVIRONMENTAL CONSULTING, LLC 21790 SW CHEHALIS COURT TUALATIN, OREGON 97062 (503)692-8118

FIGURE 2 SITE PLAN TL 200 Former Troh Legacy Landfill

Source: City of Happy Valley, Oregon http://www.ci.happy-valley.or.us/DocumentCenter/Home/View/519

Project No. Former Troh Legacy Landfill 351-14002-02 10010 Vradenburg Road Zoning Map Figure No. Happy Valley, Oregon 3

N

SE Maple SE Vradenburg Hill Road Approx 1,000 ft. Road

SE Wooded Heights Road

SE 162nd Avenue SE 172nd Avenue

Former Troh Legacy Landfill

SE Airport Road

Rock Creek

Project No. Former Troh Legacy Landfill Area of Study of THG-2014.3/351-14002-02 10010 SE Vradenburg Road Beneficial Water Use Figure No. Happy Valley, Oregon Determination 4

Former Troh Legacy Landfill

Yellow Pattern Indicates Sunrise Water Authority Service Area

Former Troh Legacy Landfill Project No. Sunrise Water Authority THG-2014.3/351-14002-02 10010 SE Vradenburg Road Service Area Figure No. Happy Valley, Oregon 5

Former Troh Legacy Landfill

Project No. Former Troh Legacy Landfill THG-2014.3/351-14002-02 10010 SE Vradenburg Road Water Rights Figure No. Happy Valley, Oregon 6

ATTACHMENT A WATER WELL LOGS

Page 1 of 1 STATE OF OREGON CLAC 68977 WELL I.D. LABEL# L 107851 WATER SUPPLY WELL REPORT START CARD # 201793 (as required by ORS 537.765 & OAR 690-205-0210) 7/19/2012 ORIGINAL LOG # (1) LAND OWNER Owner Well I.D. First Name Last Name (9) LOCATION OF WELL (legal description) Company NEW LIFE MISSIONARY CHURCH County CLACKAMAS Twp 1.00 S N/S Range 3.00 E E/W WM Address 6220 SE 92ND AVE Sec 30 NE 1/4 of the SW 1/4 Tax Lot 00300 City PORTLAND State OR Zip 97266 Tax Map Number Lot (2) TYPE OF WORK New Well Deepening Conversion Lat ° ' " or DMS or DD Alteration (complete 2a & 10) Abandonment(complete 5a) Long ° ' " or DMS or DD

(2a) PRE-ALTERATION+ Dia From To Gauge Stl Plstc Wld Thrd Street address of well Nearest address Casing: 9747 SE 172ND AVE Material From To Amt sacks/lbs HAPPY VALLEY OR 97086 Seal: (10) STATIC WATER LEVEL (3) DRILL METHOD + Rotary Air Rotary Mud Cable Auger Cable Mud Date SWL(psi) SWL(ft) Existing Well / Pre-Alteration Reverse Rotary Other Completed Well 6/27/2012 211.5 (4) PROPOSED USE Domestic Irrigation Community Flowing Artesian? Dry Hole? Industrial/ Commericial Livestock Dewatering WATER BEARING ZONES Depth water was first found 271.00 + Thermal Injection Other SWL Date From To Est Flow SWL(psi) SWL(ft) (5) BORE HOLE CONSTRUCTION Special Standard (Attach copy) 7/27/2012 271 343 35 211.5 Depth of Completed Well 343.00 ft. BORE HOLE SEAL sacks/ Dia From To Material From To Amt lbs 10 0 50 Bentonite 0 50 34 S 7.62 50 343

(11) WELL LOG Ground Elevation How was seal placed: Method A B C D E Material From To Other POURED IN TOP SOIL 0 1 Backfill placed from ft. to ft. Material BROWN CLAY 1 28 Filter pack from ft. to ft. Material Size GRAY CLAY 28 43 MEDIUM HARD GRAY BASALTS 43 230 Explosives used: Yes Type Amount MEDIUM COARSE MULTI-COLORED GRAVEL 230 343 (5a) ABANDONMENT USING UNHYDRATED BENTONITE Proposed Amount Actual Amount

(6) CASING/LINER + Casing Liner Dia From To Gauge Stl Plstc Wld Thrd 6 1 343 .250

Shoe Inside Outside Other Location of shoe(s) 343 Temp casing Yes Dia From To (7) PERFORATIONS/SCREENS Perforations Method Screens Type Material Date Started6/20/2012 Complete 6/27/2012 Perf/ Casing/ Screen Scrn/slot Slot # of Tele/ d Screen Liner Dia From To width length slots pipe size (unbonded) Water Well Constructor Certification I certify that the work I performed on the construction, deepening, alteration, or abandonment of this well is in compliance with Oregon water supply well construction standards. Materials used and information reported above are true to the best of my knowledge and belief. License Number Date (8) WELL TESTS: Minimum testing time is 1 hour Signed Pump Bailer Air Flowing Artesian Yield gal/min Drawdown Drill stem/Pump depth Duration (hr) (bonded) Water Well Constructor Certification 35 340 2 I accept responsibility for the construction, deepening, alteration, or abandonment work performed on this well during the construction dates reported above. All work performed during this time is in compliance with Oregon water supply well construction standards. This report is true to the best of my knowledge and belief. Temperature 52 °F Lab analysis Yes By Water quality concerns? Yes (describe below) TDS amount License Number 1738 Date 7/17/2012 From To Description Amount Units Signed VANCE WAGNER (E-filed) Contact Info (optional) OLSEN-PULLIAM WELL DRLG 503-665-3353

ORIGINAL - WATER RESOURCES DEPARTMENT THIS REPORT MUST BE SUBMITTED TO THE WATER RESOURCES DEPARTMENT WITHIN 30 DAYS OF COMPLETION OF WORK Form Version: