DEQ SITE ASSESSMENT PROGRAM – SITE STRATEGY RECOMMENDATION

Site Name: Marx‐Whitaker Sediment Source

EPA CERCLIS Number: None.

DEQ ECSI Number: 4166

Site Address/Location: Sediment contamination in Marx‐Whitaker Sub‐basin of Columbia Slough, T/R‐S: 1S/2E‐23 Latitude range: 45° 33’ 35.24’’ to 45° 33’ 40.2’’ Longitude range: 122° 31’ 40.1’’ to 122° 32’ 6.87’’ Main sediment contamination source is believed to be from tax lots: 1N2E23CD 1700, 1800, 1900, 1402; and 1N2E23CC 0300, 0400, 0500 & 0600.

Recommendation By: Chuck Harman, Site Assessment Section, Department of Environmental Quality (DEQ) Northwest Region Office (NWR)

Approved By: Sally Puent, Manager, Site Assessment Section, DEQ‐NWR

Date: October 2004

Background

The Marx‐Whitaker Sediment Source refers to a sub‐basin of the Columbia Slough watershed, located in northeast Portland, where high concentrations of pesticide‐contaminated sediment have been found. Sediment contamination in the Marx Whitaker sub‐basin has been extensively sampled and potential sources evaluated by the City of Portland beginning in 1995. The evaluations and analysis work performed in the Marx‐Whitaker sub‐basin are part of the City’s overall effort to clean up contaminated sediments in the Columbia Slough.

Since 1993 the City of Portland has been under a consent order from the Oregon Department of Environmental Quality (DEQ) to address contamination in the Columbia Slough. The City performed a risk‐evaluation of the Marx‐Whitaker sub‐basin in December 1997 and identified several selected pesticides and petroleum hydrocarbons in sediment as a threat to benthic life, and 2,2‐bis[p‐chlorophenyl]‐1,1‐dichlorethylene (DDE) in sediment as a threat to piscivorous birds that forage there.

DEQ NWR Site Assessment has received several reports regarding the City of Portland’s evaluation of the sediments in the sub‐basin and investigations. The conclusions reached from those investigations were that the major sources of the pesticide contamination were several large tracts of land located about 3200 feet south and upslope from the waterway. The main

1 Marx-Whitaker Sediment Source – Strategy Recommendation suspected upland sources are several properties that are being managed as farm land by two different farm families. The lands are farmed to grow vegetable crops during the growing season. Some of the farm‐managed properties are being leased from the City of Portland by one of the two farm managers.

This evaluation is different than typical screenings performed for contaminated sites in Oregon. For this screening DEQ is primarily evaluating the threats posed by the contamination that is present in the sediments of the Marx‐Whitaker sub‐basin and documenting the work that has been done to determine upland sources of the contamination. DEQ is not evaluating the exposure threats at the properties that are considered to be the upland sources of the sediment contamination.

DEQ is performing a screening of the Marx‐Whitaker Sediment Source area due to threats to the environment identified in the City of Portland (COP) risk assessments. This screening summarizes the past investigations, identifies potential responsible parties for possible cleanup actions and recommends a cleanup action priority for the sub‐basin.

Physical Setting

‐ Site Description and Local Land Use

The Marx‐Whitaker (M‐W) sub‐basin of Whitaker Slough, a reach of the Columbia Slough, lies east of NE 122nd Avenue between NE Whitaker Way and NE Marx Street in Portland, Oregon, as shown in Figure 1. The sub‐basin channel has been filled with soil to the east of COP stormwater outfall 104/105.

The sub‐basin channel is heavily vegetated, largely with reed canary grass. Water flow in the sub‐basin varies with rainfall. During dry periods, a narrow (1 to 1.5 m in width), shallow (0.2 to 1m in depth) groundwater‐fed stream flows through the sub‐basin. During period of heavy rainfall the sub‐basin may fill from bank to bank with runoff from the surrounding area.

The general land use in the area surrounding the sub‐basin is largely commercial and light industrial businesses. The area is zoned Industrial. Figure 2 is an aerial photograph taken in 2002, acquired from the City of Portland’s on‐line mapping tool (Portland Maps), which shows the general area directly around the sub‐basin. Despite the heavy development and small riparian corridor the site is still attractive to wildlife, and numerous species of birds and mammals have been observed in the sub‐basin during past site visits by City of Portland personnel and city‐hired contractors. The locations of storm‐sewer outfalls that empty into the sub‐basin are also indicated on Figure 2.

The closest current residential area to the M‐W sub‐basin is about 1500 feet to the south and at a higher elevation. The sub‐basin is located in an area that has 12 to 25 percent of residents with income below the poverty level according to the 2000 U.S. Census, which is indicated in Figure 3, a map printout acquired from EPA’s Site Information database (EPA SITEINFO, 2004).

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‐ Geology and Groundwater

Geology information has been summarized from existing environmental assessment reports and from Oregon Water Resources Department (OWRD) well logs for the area around the Marx‐Whitaker sub‐basin area.

The Marx‐Whitaker sub‐basin is located in the Columbia River flood plain physiographic province of the Portland Basin, at an approximate elevation of 25 feet above mean sea level. The area is underlain by Columbia River late Pleistocene fluvial deposits, which are underlain by the Troutdale Formation, a Pleistocene‐age sand and gravel aquifer (also known as Troutdale Gravel Aquifer, or TGA). The TGA is underlain by Pliocene age sandstone deposits and deeper by Miocene to Eocene age Columbia River Basalt.

A review of water supply well logs and boring hole logs from OWRD on‐line well logs for wells installed in the nearby area describe subsurface soils as silty sands, sand and gravels and silty gravels. Groundwater has been found as shallow as 6 feet below ground surface (bgs).

‐ Soils

The soils in the area surrounding the Marx‐Whitaker sub‐basin have been disturbed significantly by development in the area and much of the ground is covered by buildings, concrete or asphalt. The Multnomah County soil survey describes the 3 types of native soils in the area around the sub‐basin as – (a) Rafton silt loam – protected; a very poorly drained soil formed in recent alluvium, some of which is mixed with volcanic ash; and (b) Sauvie silty clay loam; a poorly drained soil formed in recent alluvium, with some mixing of volcanic ash; (c) Quafeno loam; 0 to 3 percent slopes, consisting of moderately well drained soils that formed in old alluvium. The Rafton and Sauvie soils are hydric soils, which are typically found in wetland environments.

‐ Hydrology and Surface Waters

The Marx‐Whitaker sub‐basin comprises the eastern‐most portion of the Whitaker Slough, which is a 5‐mile long tributary of the Columbia Slough. The Columbia Slough is an approximately 18‐mile long waterway that stretches from Troutdale, Oregon and flows westward to its mouth at the Willamette River. The Multnomah County Drainage District (MCDD), who maintains water levels in the Slough year‐round, primarily for flood control purposes, heavily controls flow in the Columbia Slough waterway. Total precipitation in this area averages 39.9 inches each year.

The Marx‐Whitaker sub‐basin is primarily fed by storm‐sewers that deliver runoff from surrounding roads, commercial areas, residential neighborhoods and, as already noted, areas within its watershed that are still managed as farm land. During dry periods there is a small stream flow supplied by groundwater base flow into the sub‐basin.

3 Marx-Whitaker Sediment Source – Strategy Recommendation

Storm sewer outfall locations have been denoted on Figure 2. For the purposes of identifying the possible sources of the pesticide contamination, it is important to understand what areas are drained to which outfalls. Figure 4 is a 2002 aerial photograph that has been overlaid with the rough boundaries of the drainage basins for each of the outfalls that empty into the Marx‐ Whitaker sub‐basin. Detailed drainage basin outlines are provided on a large map “Marx‐ Whitaker Drainage Basin” (printed 08/13/2004)a. As Figure 4 shows, outfall 104b (yellow outline), which is usually identified as the NE 128th and Whitaker outfall, receives the majority of it’s runoff from the residential and farm managed properties located up gradient from the sub‐basin.

Site History

The City of Portland has performed extensive studies of the Marx‐Whitaker sub‐basin. One of the first studies of Columbia Slough sediments was performed in 1991. Data from those samples indicated that the concentrations of several metals ‐ antimony, silver, lead, thallium and zinc posed a threat to benthic invertebrates and other wildlife in the Whitaker Slough. The 1991 sediments were not analyzed for organic contaminants.

In 1994 the City of Portland conducted an extensive sampling effort throughout the Columbia Slough system. Over 300 sediment and fish tissue samples were collected throughout the Columbia Slough. Using the collected data, the City developed a Screening Level Risk Assessment (SLRA) that prioritized sediment samples based upon an exposure risk model for human (food chain) and ecological receptors. The Columbia Slough sediment sampling data, which included the sampling performed in 1991, were evaluated through human health and ecological risk models. A total risk score was established for each sediment sample by adding up individual receptor‐specific hazard scores. The City then established four levels of total (cumulative risk) – A, B, C and D, in order to establish a prioritization system for addressing the sediment contamination in the Slough. The ten highest scoring samples were ranked as Priority A. The next 24‐highest scoring sediments were ranked as priority B sediments. One of the 1991 sediment samples in the Marx‐Whitaker sub‐basin (sample ID – EDWTS451600) was ranked as a B‐level priority for the metals cited in the first paragraph. The 1991 M‐W sediment sample was ranked as the 27th highest exposure risk sample of the 300 sediment samples analyzed.

In 1997 the City performed a detailed analysis of possible sources of contaminants to the Marx‐ Whitaker sub‐basin that looked at a broader set of contaminants in addition to metals. The sampling detected six pesticides routinely and at concentrations, on average, ten times higher than the average concentrations measured in sediments across the entire Columbia Slough. More details of this work are presented in the Investigation History section below.

The Multnomah County Drainage District (MCDD), on several occasions prior to 1983, dredged out the sub‐basin when it would fill with sediment. The last removal of dredge materials in the sub‐basin by MCDD occurred in 1983. Since 1983, MCDD has dredged the center channel of the

a The large BES map is not provided with this report, but will be kept in the Environmental Cleanup Site Information (ECSI) files at DEQ NWR for reference.

4 Marx-Whitaker Sediment Source – Strategy Recommendation sub‐basin and piled the dredge spoils on the banks, a practice known as “side casting”. This practice occurred in 1989, 1990, 1994 and 1997.

The upland drainage area for the 128th and Whitaker outfall consists primarily of residential properties, the farm managed areas and an elementary school, as shown in Figure 4. Figure 5 is a map showing the land management and ownership in the immediate area around the farm lands. Mr. Al Garre owns tax lots 1700 (5.87 ac.) and 1402 (4.12 ac.), the area bordered in green, and leases the remaining 15.71‐acres (tax lots 1900, 1800, 1200 and 1100) from the City of Portland, the area bordered in red. The 15.89‐acres of farm land to the west (tax lots 300, 400, 500, 600), bordered in blue, are owned and operated by the Rossi Family (Contact: Mr. Joe Rossi).

At the beginning of this evaluation, DEQ contacted both farm managers and requested information regarding their operations that would be pertinent to this report. No materials from either farm were provided to DEQ.

DEQ Site Assessment has reviewed DEQ Water Quality Division correspondence regarding the storm water runoff from the agricultural areas into the Marx‐Whitaker sub‐basin. The letters in the file predominantly discuss soil erosion and runoff concerns from the Garre‐managed farm lands. There is no correspondence in the file that indicates that the Rossi Farms property has been identified as a specific source of sediment to the Marx‐Whitaker sub‐basin.

Both DEQ and City of Portland water quality inspectors have observed runoff from the farm areas onto surface roads along the north side of the farm lands on several occasions. There are several input points where soil erosion from the farm‐managed areas has been observed entering into the storm sewer system. Locations of catch basins or drains that have received storm water runoff, based upon the reviewed records, are indicated on Figure 5. There is also a catch basin located on the Garre‐managed, Portland‐owned farm lands that has been observed receiving stormwater laden with suspended solids. This catch basin is also identified on Fig 5.

Investigation History

DEQ has reviewed several studies and sets of data that have addressed contaminants in the Columbia Slough and Marx‐Whitaker sub‐basin to support this strategy recommendation. The reports described below do not include all of the reports and documentation that has been produced as part of the overall work on the Columbia Slough sediment contamination, but do constitute the main body of work that has been performed to date to evaluate the sediment contamination in the Marx‐Whitaker sub‐basin. Each report’s findings are summarized and important facts are presented below.

A. Summary Report, Screening‐Level Risk Assessment, Columbia Slough Sediment Remedial Investigation/Feasibility Study (Columbia Slough Sediment Project), February 1995, Prepared for City of Portland, Bureau of Environmental Services; Prepared by Parametrix, Inc. and Oman/Jerrick Associates.

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This report summarizes the findings of the sediment sampling performed in the Columbia Slough during 1991 and 1994. In addition, this report presents the highest priority sediment samples (denoted as Priority A – highest and Priority B – second tier) based upon the risk assessment evaluation of the collected sediment data. There was one Priority B site in the Marx‐ Whitaker sub‐basin, from 1991 (EDWTS451600), that the risk model measured as a threat to benthic life and piscivorous species. The Priority B sites were recommended for further investigation.

B. Source Investigation of Contaminants in the Whitaker Slough Reach of the Columbia Slough, City of Portland Industrial Stormwater Program, October 1997, City of Portland Environmental Services.

This evaluation was performed to further evaluate pollutant sources to the Marx‐Whitaker sub‐ basin due to the detections of several metals (antimony, lead, silver, thallium and zinc), which caused the Priority B ranking. City of Portland staff performed site inspections of 29 industrial and commercial facilities within the sub‐basin watershed, including the Garre farm operation. The report notes that Rossi Farms has part of their operation within the drainage basin for the 128th and Whitaker outfall sub‐basin (see Figures 4 and 5), but no inspection of their lands was apparently performed.

No specific conclusions were made as part of this report. Each of the 29 inspected facilities was provided with recommended storm water best management practices (BMPs). In the letter to Mr. Garre the City of Portland’s Bureau of Environmental Services recommended several approaches to address observed soil erosion problems on the farm land.

C. Final Sediment Characterization Report and Risk Assessment, Marx‐Whitaker Subbasin of Whitaker Slough, Early‐Action Remedial Activities, Columbia Slough Sediment Project, Ecology and Environment, Inc., prepared for Portland Bureau of Environmental Services, August 1998.

This report was designed to address several issues related to the metals‐contaminated sediment in the Marx‐Whitaker sub‐basin. The tasks defined in the report included – (a) Delineate the extent of sediment contamination; (b) Evaluate the significance of the area as a habitat for aquatic life and wildlife; (c) Determine the possible effects of the contamination on key ecological receptors; and (d) Determine if the area supports large fish that may attract anglers and, if so, evaluate the potential risks to individuals that may eat fish from the sub‐basin. As part of the work for this evaluation, E&E collected eight additional sediment samples from locations along the length of the sub‐basin and tested them for a broader range of chemical and physical parameters than had been done in 1991. Figure 6 shows the sampling locations for 1997 sediment samples.

The new data collected for this report showed that six pesticide and pesticide degradation products (DDD, DDE, DDT, dieldrin, endosulfan II, and endosulfan sulfate) and petroleum hydrocarbon concentrations were elevated in sediment throughout the sub‐basin. The new sediment data also showed that the metals of concern from the 1991 sediment work were not present at levels that posed a risk to ecological species in the sub‐basin.

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The report concluded that survival and growth of benthic life was impaired by several pesticides (dieldrin, endosulfan II and DDT) and that piscivorous birds, such as the great blue heron, may be adversely affected by sediment DDE contamination. In addition, the report concluded that since there were no fish of sufficient size to support fishing, that there was no risk to humans via fish consumption.

D. Stormwater and Storm‐Sewer Sediment Report for the Marx‐Whitaker Sub‐basin of Whitaker Slough, Columbia Slough Sediment Project, Early Remedial Action, Phase II, Ecology and Environment, Inc., prepared for City of Portland, Bureau of Environmental Services, April 1999.

This report presents findings from a follow‐up investigation performed to identify the principal sources of contamination measured in the 1997 sediment sampling in the Marx‐Whitaker sub‐ basin. This investigation collected stormwater and storm‐sewer sediment at the outfalls and at selected upstream locations and analyzed them for pesticides, petroleum contamination, storm flow volumes, total suspended solids and soil particle size.

Storm event sampling was performed at or near outfalls and at points within the up gradient storm‐sewer network for the explicit purpose of differentiating flows from sub‐sections of the stormwater system’s catchments areas. Figure 7 shows a map from this report that shows the sampling locations. The storm sewer system lines have been highlighted to more clearly show the catchment areas for each of the outfalls and the selected sampling locations. Catch basins along NE Shaver Street, at intersections with NE 129th and NE 130th, where stormwater runoff from the farms had been observed entering the storm sewer system, were sampled. In addition, a catch basin at the intersection of NE Shaver and NE 136th Avenue was sampled. Stormwater that enters the NE Shaver catch basins at 129th and 130th eventually drains into the NE 128th and Whitaker outfall. The NE Shaver and NE 136th outfall is also an upstream point that eventually drains into the NE 128th and Whitaker outfall, but primarily drains a residential neighborhood.

Several types of samples were collected as part of this report. The target size and duration of an acceptable storm was set a priori at between 0.2 and 0.6 inches of rainfall over an 8 to 20 hour period, preceded by a 72‐hour dry period (< 0.1 in. of rain). During a period of no precipitation, sediments were sampled near the outfalls and at the selected storm sewer system locations. Secondly, during rainfall events, stormwater was sampled at the selected locations. The storm‐ event water samples that were acquired included – (a) “first flush” grab samples that captured stormwater approximately 15 minutes after rainfall began; and (b) flow‐weighted composite samples, where 600 mL aliquots of stormwater were collected periodically over a three hour period after a “continuous” flow was established in the storm sewer system.

Figures 8 through 10 show storm sewer sediment sample concentrations for the pesticides of concern acquired from the M‐W sub‐basin outfalls and upstream sewer system locations. These figures show the highest concentrations for the selected pesticides of concern were in sediments collected at the NE 128th and Whitaker outfall. The second‐ and third‐highest detections of those pesticides were typically found in the upstream 129th and 130th storm sewer locations. The only exceptions were that DDD and DDE were measured in the OF 104/105 outfall sediments. The

7 Marx-Whitaker Sediment Source – Strategy Recommendation authors of the report surmised that pesticides measured in OF 104/105 sediments might result from contaminated sediments coming from the 128th and Whitaker outfall, given its proximity to OF 104/105.

Figure 11 shows storm sewer sediment sampling results for petroleum hydrocarbons. The highest concentrations for petroleum hydrocarbons were from outfalls – OF 101 and OF 128th & Marx ‐ that drained largely roads and parking areas in the commercial/industrial areas closer to the sub‐basin (see Figure 4).

Figures 12 to 15 show “first flush” storm sample results taken from the outfalls and catch basins in December 1998. The first flush results for the pesticides (Figures 12 and 13) show that the 129th and 130th catch basins captured the heaviest loads of the pesticides in stormwater. Figure 14 shows the TSS measurements, again indicating that the heaviest sediment loads are coming from the two catch basins near the farm‐managed lands.

Figure 15 shows that petroleum hydrocarbon contaminated runoff was highest at the 128th and Marx outfall. This outfall captures runoff from areas that drain largely paved parking lots and industrial areas in close proximity to the Marx‐Whitaker sub‐basin.

This report concluded that the agricultural fields south of NE Shaver Street were the “ultimate source of much of the pesticide contamination”. Secondly, that petroleum contamination was entering the sub‐basin from multiple sources that discharged stormwater into the sub‐basin.

E. Pollutant Removal Facility Evaluation for the Marx‐Whitaker Subbasin of Whitaker Slough, prepared for City of Portland Bureau of Environmental Services, by Parametrix, July 2003.

This report was prepared for the City of Portland with the purpose of presenting several alternatives for pollutant removal facilities (PRFs) that might eliminate or reduce pesticide‐ contaminated suspended solids from upland runoff areas that were discharging into the sub‐ basin via the 128th and Whitaker outfall. This evaluation included additional stormwater sampling from of the 128th and Whitaker outfall catchment and subcatchments. Figure 16, which is taken directly from the report, shows the sampling locations for this study. The table below summarizes each of the sites.

Sampling Subcatchment(s) Description Site Site 2 WHIT2‐RES Combined flow, storm drains flowing from east to west, at 12280 NE WHIT2‐AG Prescott. WS10A WHIT10A Storm drain flowing from west on NE Sandy Blvd at 125th Place. WS13A/12Aa WHIT13A Storm drain flowing from east on NE Sandy Blvd at 131st Place. WS11A All of the above Storm drain flowing from south at 12800 NE Sandy Blvd (combined flow from all of the above sites. Just prior to 128th and Whitaker outfall. a – Sample for Event 1 (3/31/03) was collected at WS13A. Sample for Event 2 (4/23/03) was collected at WS12A (NE Sandy Blvd at 125th Place), which represents flows from the same drainage area as WS13A.

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The sampling was performed during two separate storm events in the spring of 2003, one on March 31 and the second on April 24. Water samples were tested for pesticides and several other water quality parameters, including total suspended solids (TSS) and total dissolved solids (TDS). For the sake of brevity, only a few examples of the results are presented in this screening. Figure 17 shows the mass transport results for 4,4’‐DDT for both storm events. Similar results can be observed in Figure 18, the mass transport results for Dieldrin. These results are similar to results for the other pesticides, indicating that significant volumes of the pesticide‐contaminated soils are coming from the subcatchment that includes the farmlands. Finally, Figure 19 presents the TSS data, further illustrating that the soil/sediment load to the 128th and Whitaker outfall is predominantly from the area that drains the farm‐managed lands.

The report concluded from the mass loading analysis that 60 to 100 % of the pesticide loading being discharged to the 128th and Whitaker outfall was from the agricultural fields.

Analytical Results

Table 1 presents a summary of selected analytical results, primarily for organochlorine contaminants, for sediment sampling that has been performed in the Marx‐Whitaker sub‐basin, compared to the greater Columbia Slough sediment results. This table is a direct copy of Table 4‐1 from the April 1999 Ecology and Environment, Inc. report, with the exception that DEQ Screening Criteria concentrations have been added to the right side. The table clearly illustrates that the average concentrations of pesticides measured in the sub‐basin and storm‐sewer sediments are much higher than the concentrations found throughout the Columbia Slough.

In addition, Table 1 illustrates that the concentrations of the presented pesticides are much greater than the Columbia Slough Baseline concentrations established by DEQ for the purposes of prioritizing cleanup actions for sediments in the Slough. The Columbia Slough baseline values are statistically based concentrations, developed from the 1991 and 1994 sediment sampling events, which represent a system‐wide “ambient level” for multiple contaminants that were detected. The pesticide concentrations in sediment in the Marx‐Whitaker sub‐basin exceed DEQ‐established values for protection of aquatic species by an order of 10 to 100 times.

The storm sewer sediment and storm event data presented in the Investigation History section, particularly the results from the April 1999 and July 2003, do not provide a complete accounting of all possible pesticide‐contaminated sediment sources to the Marx‐Whitaker sub‐basin. Nonetheless, the results, coupled with the past visual observations of runoff from the farms entering the storm sewer system, show that the runoff from the farm‐managed lands is a large, ongoing source of contaminated sediments to the sub‐basin and the most‐likely source of discharges since 1983.

Contaminant Pathways

As part of every screening, DEQ typically evaluates the most likely ways that human or ecological receptors could be exposed to suspected or known site contaminants. The contaminant pathway analysis does not constitute a complete Conceptual Site Model (CSM),

9 Marx-Whitaker Sediment Source – Strategy Recommendation but is provided to establish possible exposure pathways that are of the most concern based on the available information.

Soil – DEQ recognizes three possible soil exposure pathways:

(a) There is the threat of direct contact exposure for humans or ecological species along the banks of the sub‐basin if contaminated sediments had been cast up on the banks previously. Soils on the banks of this area should be evaluated during future remedial work. (b) One possible soil exposure pathway that could occur during future sediment removal and disposal activities. If sediments are dredged from the sub‐basin channel there could be exposure to workers either through direct contact with sediments or via dust inhalation, should the sediments be allowed to dry before transport; (c) How and where the sediments are disposed of may be a concern for persons performing the disposal work and to any persons who might be exposed to the sediments via direct contact or dust inhalation if the disposal is done in locations accessible to the public. In addition, ecological exposure to contaminated soils at the disposal location would need to be evaluated;

Air – The sediment contaminants of concern have very low vapor pressures and would not result in significant vapor concentrations in air. A possible air exposure pathway could be via inhalation of airborne dust that might be generated during sediment removal activities. However, precautionary measures could be taken during any removal activity to address this potential exposure pathway.

The sediments in the Marx‐Whitaker sub‐basin should not represent a significant exposure threat via the air pathway.

Groundwater – The contaminants of concern for the Marx‐Whitaker sub‐basin sediments all have low solubility and there is a low likelihood that they would enter into an aqueous phase and enter local groundwater supplies. In addition, bank seepage and base flow from shallow groundwater that flow into the sub‐basin during the drier seasons, indicate an upward hydraulic gradient that would be expected to block transport of soluble contaminants into deeper groundwater. Thirdly, the soils in the immediate vicinity of the sub‐basin are characterized as very poorly to poorly drained, indicating that downward flow of pore waters would be impeded and thus not likely to transport contaminants into the subsurface.

However, this site is located within the City of Portland’s Columbia South Shore well field wellhead protection area and monitoring of local groundwater during future investigative or remedial activities should be performed as a precaution.

Surface waters/sediment – The National Wetland Inventory (NWI) indicates that the Marx‐ Whitaker sub‐basin is a palustrine aquatic‐bed, permanently flooded wetland. There are several

10 Marx-Whitaker Sediment Source – Strategy Recommendation other wetland areas downstream in the Whitaker Slough and near the sub‐basin. Figure 3 shows the nearby wetlands and their designations from the NWI.

The Whitaker Slough is part of a near‐continuous east‐to‐west wildlife corridor of water and vegetation close to the Columbia River. Waterfowl and songbirds use areas of the Marx‐ Whitaker sub‐basin for migratory rest stops and wintering habitat.

The Columbia Slough is listed as a water quality limited body on the 2002 303(d) list for several parameters ‐ iron and manganese in the water column and temperature. The Columbia Slough was also listed for toxic parameters on the 1998 303(d) list – DDE, DDT, lead, dioxins, and polychlorinated biphenyls (PCBs), based on those contaminants being found in fish tissues. The 2002 303(d) list no longer lists the toxic contaminants because a total maximum daily load (TMDL) has been written for these contaminants. However, the delisting of the Columbia Slough for toxics is not based upon newer data indicating elimination or reduction of the listed toxic substances, and therefore, they will continue to be a concern for the foreseeable future.

An ecological risk analysis of the Marx‐Whitaker sub‐basin has shown that concentrations of organochlorine pesticides in sediments pose a threat to aquatic and terrestrial species that are present in the sub‐basin.

The surface water/sediment pathway presents a known risk to ecological receptors that needs to be addressed.

Summary and Conclusions

Sediments in the Marx‐Whitaker sub‐basin contain high levels of several organochlorine pesticides that have been determined to be harmful to aquatic and terrestrial species based upon a risk assessment. Furthermore, the pesticide concentrations found in the sub‐basin greatly exceed benchmarks for the Columbia Slough and DEQ‐established screening criteria for sediments. The City of Portland has evaluated potential sources of sediment contamination and concluded that the major sources of the organochlorine pesticides are farm‐managed properties located approximately 1.5 miles to the north.

The potentially responsible parties for the Marx‐Whitaker sub‐basin sediment contamination are (a) City of Portland Parks and Recreation Department (tax lots 1100, 1200, 1800 and 1900); (b) Mr. Albert Garre (tax lots 1402 and 1700); and (c) Rossi Farms (tax lots 300, 400, 500 and 600). It is possible that other, smaller properties, including residential properties within the catchment of the sub‐basin, may be contributors of pesticide‐contaminated sediments to the sub‐basin. Nonetheless, direct observation by water quality professionals from DEQ and the City of Portland, combined with the three storm sewer and sediment investigations, show that the farm‐managed properties have contributed a significant portion of the contaminated sediment that has been measured in the Marx‐Whitaker sub‐basin.

The Marx‐Whitaker sub‐basin is a high priority for a Remedial Investigation/Feasibility Study (RI/FS). An RI/FS is appropriate given the amount of investigation that has been conducted to

11 Marx-Whitaker Sediment Source – Strategy Recommendation date. The City and the farm managers should consider early actions to address further release of contaminants to the slough and to evaluate cleanup options for contaminated sediment should also be considered.

This report, in combination with the referenced reports maintained at DEQ in the ECSI files, constitutes a Preliminary Assessment Equivalent (PAE).

Recommendation(s)

1. The City of Portland Bureau of Environmental Services and the upland farm managers (Mr. Al Garre and Mr. Joe Rossi) should collaborate on a plan to clean up contaminated sediments in the Marx‐Whitaker sub‐basin. A major component of this plan is a strategy for instituting source control measures that will great reduce or eliminate the delivery of contaminated upland soils into the sub‐basin.

2. Future remedial actions for the Marx‐Whitaker sub‐basin will most likely include removal of the sediments that have accumulated in the waterway since about 1983, including areas where sediments have been historically side‐cast. Once removed, sediments should be evaluated to determine the proper method for disposal.

Referrals

A. This site will be proposed for listing on the Confirmed Release List. B. This site will be proposed for listing on Inventory of Hazardous Substance Sites.

Site Regulatory Status

This site is listed on DEQ’s ECSI database, #4166.

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Attachments FIGURES

Figure 1: Map showing Marx‐Whitaker sub‐basin and upland source areas in NE Portland.

Figure 2: 2002 aerial photograph of Marx‐Whitaker sub‐basin showing local land use.

Figure 3: EPA Site Info map for two‐mile radius showing local income levels, streets and water quality limited streams.

Figure 4: Aerial photograph outlining several Marx‐Whitaker outfall drainage basins.

Figure 5: Aerial photograph showing outlines of land ownership on upland farm lands.

Figure 6: Marx‐Whitaker sub‐basin map showing locations of 1998 sediment sampling locations.

Figure 7: Sampling location map for 1998 storm sewer and stormwater flush sampling.

Figure 8: Storm sewer system sediment data from October 1998 (DDT, DDE, DDD).

Figure 9: Storm sewer system sediment data from October 1998 (Dieldrin, Endosulfan I & II).

Figure 10: Storm sewer system sediment data from October 1998 (Endosulfan Sulfate).

Figure 11: Storm sewer system sediment data from October 1998 (petroleum hydrocarbons).

Figure 12: First flush stormwater sampling data from December 1998 (DDT, DDE, Dieldrin).

Figure 13: First flush stormwater sampling data from Dec. 1998 (Endosulfan I & II, and Sulfate).

Figure 14: First flush stormwater sampling data from December 1998 (Total suspended solids).

Figure 15: First flush stormwater sampling data from Dec. 1998 (Petroleum hydrocarbons).

Figure 16: Map showing storm sewer system sampling locations for Spring 2003 Pollution Reduction Facility evaluation.

Figure 17: Storm runoff mass transport measurements for DDT during two spring storm events.

Figure 18: Storm runoff mass transport measurements for Dieldrin during two spring storm events.

Figure 19: Storm runoff mass transport measurements for TSS during two spring storm events.

TABLES

Table 1: Comparison of Marx‐Whitaker Sediment Pesticide Concentrations to Greater Columbia Slough.

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References

1. Ecology and Environment, Inc., “Stormwater and Storm‐Sewer Sediment Report for the Marx‐ Whitaker Sub‐basin of Whitaker Slough, Columbia Slough Sediment Project Early Remedial Action, Phase II,” Prepared for City of Portland Bureau of Environmental Services, April 1999.

2. Ecology and Environment, Inc., “Final Sediment Characterization Report And Risk Assessment, Marx‐Whitaker Subbasin of Whitaker Slough, Early‐Action Remedial Activities, Columbia Slough Sediment Project,” Prepared for Portland Bureau of Environmental Services, August 1998.

3. Metro Regional Government, File Transfer Protocol (FTP) map data for ecological information, URL: ftp://ftp.metro‐region.org/dist/gm/goal5/maps/, April 2004.

4. Oregon Department of Environmental Quality (DEQ), Water Quality Division, “2002 Water Quality Limited Streams 303(d) List,” URL: http://www.deq.state.or.us/wq/303dlist/ 303dpage.htm, April 2004.

5. Oregon Department of Environmental Quality (DEQ), Underground Storage Tank (UST) Program, letter from Andree Pollack (DEQ‐UST) to Charles W. Gaskill, June 30, 1989.

6. Oregon Department of Fish and Wildlife (ODFW), “Fish Distribution/Habitat Maps”, URL: http://osu.orst.edu/dept/nrimp/information/fishdistmaps.htm, Updated in February 2001.

7. Oregon Water Resources Department (WRD), Geographic Resource Identification (GRID) Well Log Database (http://deschutes.wrd.state.or.us/apps/gw/well_log/), April 2004.

8. Parametrix, “Pollutant Removal Facility Evaluation for the Marx‐Whitaker Subbasin of Whitaker Slough,” Prepared for City of Portland Bureau of Environmental Services, July 2003.

9. Parametrix, Inc., “Screening‐Level Risk Assessment, Columbia Slough Sediment Remedial Investigation/Feasibility Study,” Prepared for City of Portland Bureau of Environmental Services, February 1995.

10. City of Portland, Bureau of Water Works, “Columbia South Shore Well Field Wellhead Protection Area, Reference Manual,” June 25, 2003.

11. City of Portland, Corporate Geographic Information System (CGIS) database (a.k.a. Portland Maps), http://www.cgis.ci.portland.or.us/main.cfm, April 2004.

12. City of Portland, Environmental Services Systems Analysis, “Marx‐Whitaker Drainage Basin,” Date Printed: 08/13/2004.

13. City of Portland, Environmental Services, “Source Investigation of Contaminants in the Whitaker Slough Reach of the Columbia Slough, City of Portland Industrial Stormwater Program,” October 1997.

14. United States Department of Agriculture (USDA), “Soil Survey of Multnomah County Area, Oregon,” August 1983.

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