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Site 4: Warmhouse Beach Open DumpSite Background and History
The Warmhouse Beach Open Dump is situated on the edge of a small valley overlooking the Strait of Juan de Fuca. The dump is at an elevation of approximately 260 feet above msl on the northern coast of the Reservation, 2 miles west of the town of Neah Bay and ¼ mile south of the Strait of Juan de Fuca. The dump is surrounded by dense vegetation. Its northernmost extent is approximately 800 feet inland from the shoreline. Members of the Makah Tribe have used the dump for approximately 20 years; prior to that, the Warmhouse Beach Open Dump was used by the USAF (Claplanhoo, 1994; White Shield, 1995; Tecumseh, 1998). The Makah Tribe historically used Warmhouse Beach as a summer fishing camp. The Makah AFS reportedly used the site from World War II until 1988 to dispose of household and various hazardous wastes. Materials disposed of by the Makah AFS included paint cans, paint thinner, pesticides, lubricants, waste oil, asbestos-containing materials, empty barrels, and sewer sludge (Chamblin, 1994; LaChester, 1994; Olson, 1994; Ray, 1994; Shunn, 1994). Dumping reportedly began in a deep ravine that runs east and west along the south edge of the dump site. The ravine is 20 to 40 feet deep relative to the elevation of the access road where it enters the site. A bedrock ridge just to the north of the ravine runs parallel to the ravine. The top of the ridge is about 70 feet above the top of the ravine. The north side of the ridge slopes steeply to the north toward Warmhouse Beach and the Strait of Juan de Fuca. Waste materials were originally dumped into the ravine from the access road on the ravine's south side. As the ravine filled with waste material, a road embankment was constructed on top of the waste material and across the ravine from the south side to the north side. This road embankment increased the dump's accessibility and allowed additional filling of the ravine to the east and west of the original dump, where the road crosses the ravine. Subsequently, the access road was extended to the top of the ridge. Since then, waste materials have been dumped from the top of the ridge down toward the ravine to the south. Consequently, a layer of waste covers the steep hillside that faces south toward the ravine. Waste has also been dumped from the top of the ridge down toward the north and northeast.
Runoff from rainfall originates on the south side of the ridge, flows across the waste deposit on the ridge's south hillside, and flows through the waste deposit in the ravine. From the waste deposit, the main drainage pathways are to the east and west through small intermittent creeks. The watershed in which the dump is located generally drains to the north, into the Strait of Juan de Fuca and away from the known aquifers in the Waatch River valley and the Sooes River valley. The dump is 2 to 3 miles from the Waatch River valley, which is the nearest area delineated by the U.S. Geological Survey (USGS) as potentially having an aquifer. The Makah Tribe is seeking to create opportunities for economic development, including tourism, in a manner that enhances the ecology of the area and the culture of its people. Consolidation and closure of the Warmhouse Beach Open Dump is of the highest priority to the Makah Tribe. The Warmhouse Beach Open Dump contains hazardous substances, is a health hazard to people who visit the site, and has impacted wildlife in the vicinity. The adjacent beach area is prime habitat for marbled murrelet. However, murrelet nesting in the area is inhibited because crows and seagulls use the dump site. Drainage from the dump site has potentially impacted downgradient and adjacent beach areas. Kelp beds and shellfish habitat may have been or may be impacted by contaminants migrating from the dump. In addition, an historical fishing village in the area that is of archaeological value may have been impacted by the waste disposal practices. CharacterizationWaste
Based on the initial waste delineation and site characterization study performed by White Shield in 1995, Brown and Caldwell (1999) estimated the waste volume at the Warmhouse Beach Open Dump to be between 25,000 and 33,000 cubic yards. This estimate was based on a survey of the site and various test pits excavated to determine waste depth. An updated estimate of the current volume of solid waste material was developed based on waste generation rates and population. As of the end of 2003, in-place waste volumes at the dump were estimated within a range of 55,000 to 65,000 cubic yards (Ridolfi, 2003a). The active portion of the dump consists of about 7 acres at the top of the ridge, with the bulk of the waste located within the deep ravine. The dump is generally oval-shaped and aligned east-west. The dump is about 500 feet in width by 250 feet in length by up to 40 feet in depth (Ridolfi, 2003a). In the ravine at the toe of the dump, the waste extends below the surface to a depth of at least 22 feet (White Shield, 1995). Scattered debris is located along the access road to the dump; metal drums, tires, and other debris are located in the ravine west of the access road (Ridolfi, 2003a). About 1,500 people, or 492 households, use the dump for solid waste disposal (Ridolfi, 2003a). The USCG currently ships its refuse off the Reservation for disposal. Table 1 summarizes the results of the 1995 waste characterization. A waste stream analysis performed in 2002 provides more specific information about the contents of the waste that is generated on the Reservation and eventually placed in the Warmhouse Beach Open Dump (Foster, 2002; Ridolfi, 2003). Table 2 presents the results of that waste stream characterization. GeologyThe dump and the surrounding area are underlain by the Hoko River Formation, which outcrops locally. This formation is comprised of siltstone and sandy siltstone with pebble-cobble conglomerate lenses; iron-stained concretionary siltstone and sandy siltstone with minor thin-bedded quartzofeldspathic, very fine to medium-grained sandstone beds; and pebbly mudstone, mudflow breccia, sandstone dikes, and thin tuff beds (Dion et al., 1980). The Hoko River Formation dips to the northeast at approximately 30 degrees. Based on the regional dip of the formation, and the location of the surface contact with the stratigraphically lower Lyre Formation, there are potentially 2,000 feet of Hoko River siltstone beneath the landfill. The Lyre Formation, which underlies the Hoko River Formation, is comprised of conglomerate and sandstone (Dion et al., 1980). Surface WaterThe dump site is located on a "saddle" between two unnamed creeks that drain to the east and west. The "West Creek" outfalls to Warmhouse Beach approximately 1,000 feet west of the site. The "East Creek" outfalls west of Kydikabbit Point, approximately 500 feet northeast of the site. The majority of the waste at the site has been dumped into the upper portions of the East Creek and West Creek drainages. Warmhouse Beach can be accessed by a steep trail that begins at the northwest corner of the dump. The beach is used for camping, surfing, and other recreational activities (Ridolfi, 2005a). Ground WaterBased on information from the USGS, various consultants, and a 2001 hydrogeologic investigation, it is believed that there are no geologic formations beneath the dump site that meet the definition of an aquifer. Water supply studies funded by the IHS have also shown that no potential aquifers exist elsewhere within the Hoko River Formation. Therefore, it does not appear that a potential ground water pathway exists for site contaminants (Ridolfi, 2001a). Activities to Date2001 Hydrogeologic Investigation
The Makah Environmental Restoration Team completed a hydrogeologic investigation at the site in 2001 (Ridolfi, 2001a). Four soil borings were drilled, soil samples were collected from each boring, and monitoring wells were installed in the four soil borings. A ground water sample was collected from MW-03. Ground water was not encountered in the other wells. In addition, one surface water sample and one sediment sample were collected from the West Creek. The samples were analyzed for volatile organic compounds, PAHs, PCBs, gasoline-range hydrocarbons, diesel-range hydrocarbons, and 15 metals from the USEPA Target Analyte List. The chemical analyses indicated that cadmium, chromium, copper, lead, and zinc are contaminants of concern at the site. Investigation results indicate that a continuous aquifer does not exist beneath the site and that the contaminants of concern are migrating away from the dump site toward Warmhouse Beach through the surface water pathway. After being installed in 2001, monitoring wells at the site were damaged as a result of vandalism and vehicular traffic. Protective casing covers on some of the wells were destroyed, leaving the well casing open and exposed to the elements. During a site visit in October 2002, water was observed in each of the wells. However, it was not clear whether the water was rainwater that had entered through the tops of the open wells or ground water that had entered through the screened intervals. 2004 Site Investigation
In March, April, and September 2004, monitoring wells MW-01, MW-02, and MW-03 were repaired and redeveloped. Monitoring well MW-04 was buried under debris and could not be located. Well repairs included installing new watertight plugs and locking well caps and painting the protective casing covers a safety-yellow color. Bollards were constructed around wells MW-01 and MW-02 and also painted bright yellow (Ridolfi, 2004a, 2005a). In October 2004, the ground water levels in the monitoring wells were measured and four ground water samples (including one replicate) were collected to verify that contaminants were not migrating from the site via the ground water pathway. In addition, two surface water and two sediment samples were collected from both West Creek and East Creek to verify whether contaminants continue to migrate from the dump site through the surface water pathways. One surface water sample and one sediment sample were collected from nearby Classet Creek to assess background conditions (Ridolfi, 2005a). The surface water and sediment samples were analyzed for gasoline-, diesel-, and lubricating oil-range hydrocarbons and metals from the USEPA Target Analyte List. Ground WaterMetals and benzene were detected in ground water from the site. Lead was detected in two of the samples at concentrations that exceed the USEPA National Primary Drinking Water Regulations for Maximum Contaminant Level. Arsenic was detected in MW-01 at a concentration exceeding the screening levels. Other metals were each detected in at least one sample at concentrations below the screening levels. Benzene was detected in the sample collected from MW-02 at a concentration below the screening level (Ridolfi, 2005a). Surface WaterMetals and diesel-range hydrocarbons were detected in the surface water samples collected near waste debris at the site. Arsenic was the only metal detected at a concentration greater than the screening level. Arsenic was also detected at a concentration above the screening level in the background sample from Classet Creek, but that concentration was the lowest arsenic concentration detected in any of the surface water samples. Other metals were detected in several of the surface water samples at concentrations below the screening levels. Diesel-range hydrocarbons were detected only in the West Creek 001 sample. Screening levels were not available for diesel-range hydrocarbons (Ridolfi, 2005a). Conductivity measured in the field in the East Creek and West Creek samples was similar to that of the ground water samples, and one order of magnitude greater than that of the background sample. Conductivity is a measure of the ability of a solution to conduct an electrical current; because the current is transported by ions in solution, a higher conductivity reflects a greater concentration of ions in suspension. The elevated conductivity of these samples indicates surface water impacts from the dump. SedimentThe concentrations of lead, nickel, and zinc in the upstream sediment samples from both creeks exceeded screening levels. The concentrations of these metals in samples collected farther downstream in the creeks and at the background station on Classet Creek were below the screening levels, with the exception of nickel in the Classet Creek sample, which was just above the screening level. Manganese was detected at concentrations above the screening levels in samples from upstream stations, while manganese concentrations in downstream samples were below the screening levels but greater than the concentration in the Classet Creek background sample (Ridolfi, 2005a). In general, elevated metals concentrations are present in the creeks near the waste material. A decrease in metals concentrations was observed in the downstream samples. Calcium, lead, manganese, mercury, and zinc concentrations in samples from upstream stations were one order of magnitude greater than concentrations in the sample from the background station. Sodium concentrations in samples from upstream stations were more than twice the levels found at background or downstream stations. These metals are typically associated with leachate from solid waste impoundments and also contribute to conductivity. 2006 Annual Sampling
During March 2006, another round of ground water, surface water, and sediment sampling was conducted at the dump. The Makah Environmental Restoration Team intends to make this an annual or semi-annual activity, in order to provide information on trends over time, as planned in the SPIP (Ridolfi, 2005e). The March 2006 sampling event included three ground water samples from monitoring wells MW-01, MW-02, and MW-03; two sediment and two surface water samples from West Creek; two sediment and two surface water samples from East Creek; and one sediment and one surface water sample from Classet Creek (reference station). Ground WaterAnalytical results from the ground water samples collected in 2006 indicate that lead and arsenic are present at concentrations above screening levels with maximum concentrations in MW-01. These results are similar to the results for the ground water samples collected in 2004 (Nicholls and Hilgart, 2006b). Surface WaterMetals were detected in surface water samples collected from the East Creek and West Creek. In 2006, arsenic, copper, and lead were the only metals detected above screening levels in the primary surface water samples. The maximum concentrations of these metals were detected in West Creek near the waste. The majority of the metals detected in the 2006 surface water samples were at concentrations similar to those detected in the 2004 samples (Nicholls and Hilgart, 2006b). SedimentMetals and diesel-range and motor oil-range hydrocarbons were detected in sediment samples collected from East Creek and West Creek. Chromium, copper, and nickel were detected at concentrations greater than the screening levels in both the primary and reference sediment samples. Concentrations of diesel-range and motor oil-range hydrocarbons and some metals appear to decrease with distance from the waste debris. Most metals concentrations detected in 2006 were not substantially different from the concentrations detected at the same locations in 2004. In general, concentrations of diesel- and motor oil-range hydrocarbons were greater in the 2006 sediment samples than in the 2004 sediment samples (Nicholls and Hilgart, 2006b). Several metals that are typically considered good indicators of landfill leachate contamination, including calcium, iron, manganese, and sodium, were detected in samples taken from the sampling locations closest to the waste, at concentrations several times greater than those detected in the sample from the reference location. Closure OptionsThree options for landfill closure were evaluated for the USEPA in 1993: (1) minimal cover, (2) consolidation and capping, and (3) excavation and haul to a Resource Conservation and Recovery Act (RCRA)-permitted landfill. The feasibility, practicality, and cost of the three alternatives were examined based on a field assessment. Conformance with RCRA regulations for runon and runoff control, cover systems, leachate collection, landfill gas control, and post-closure care were also considered in the evaluation of closure alternatives. The evaluation concluded that the minimal cover concept would not meet regulatory requirements, nor would it be protective of human health or the environment. Excavation and haul would meet RCRA standards but would be the most costly alternative. It was recommended that the dump be closed under the consolidation and capping alternative (SAIC, 1993). Following the 1995 waste delineation/site characterization study, Brown and Caldwell estimated the costs of two alternatives: (1) in-place consolidation and closure and (2) waste excavation and export. Alternative 1 consisted of consolidating the existing waste on site and closing the consolidated waste in place. Alternative 2 consisted of excavating all of the waste and exporting it to an existing regional disposal facility. To determine the preferred disposal alternative, a cost-benefit analysis of each alternative was conducted. In this second analysis of dump closure alternatives, consolidation and closure in place still appeared to be more favorable than excavation and export to an existing landfill (Brown and Caldwell, 1999). The Brown and Caldwell studies indicate that consolidation and closure in place has higher upfront costs because of the necessary permitting and engineering required to close a landfill in accordance with Subtitle D of RCRA. However, the construction costs for this alternative are significantly lower and more easily estimated than are the costs of the waste export alternative. In-place closure requires a long-term commitment to perform post-closure monitoring of the site (Brown and Caldwell, 1999). In 2003, Ridolfi prepared a draft closure plan for the Warmhouse Beach Open Dump (Ridolfi, 2003a). Two cover configurations were explored for the final shape of the waste containment facility: a Slope Option, in which the waste would simply be regraded to a more stable slope, and a Ravine Option, in which the waste would be consolidated within the existing ravine. Both options included site drainage and access control measures, as well as site stabilization. A multi-media engineered cover would be installed over the consolidated and compacted waste. This cap would include an internal drainage layer, a passive gas-venting system, a geosynthetic barrier layer, and a growth media layer to support vegetation (Ridolfi, 2003a). Based on the recommendations made following the prior evaluations, the working assumption is that the active dump will be consolidated and closed in place using one of the two options explored in the draft closure plan, although the final configuration has not yet been selected. To support closure of the Warmhouse Beach Open Dump and comprehensively address waste-related issues, the Makah Tribe developed a solid waste management program (Ridolfi, 2003). Five options for future handling of the Makah Tribe's waste were evaluated in the 2003 solid waste management plan to support replacement of the Warmhouse Beach Open Dump and allow its closure. The five options were:
All five disposal options relied on the assumption that household hazardous waste, vehicle batteries, waste motor oil, and tires would be removed from the waste stream and shipped off site for recycling or disposal (Ridolfi 2003, 2003b). Because a transfer station would be a useful element under any of the disposal options, the Makah Tribe decided to proceed with design of the facility. (Although Options A and E did not call for a transfer station, both would be enhanced by such a facility to allow sorting and handling of the waste so that hazardous and recyclable materials can be diverted.) The U.S. Department of Agriculture (USDA)'s Rural Development Service is expected to provide funding for construction. To date, a preliminary engineering report (Ridolfi, 2003b), an environmental report (Ridolfi, 2003c), and a Phase I environmental site assessment (Ridolfi, 2003f) have been prepared for the proposed waste transfer station. Funding for the design was secured through the USEPA and IHS, and additional funding is expected to come from the Tribal Solid Waste Interagency Workgroup. The design of the new transfer station has been completed and construction documents are currently being prepared. Planned ActivitiesThe Tribe considers this site a high priority (Priority A). The following activities are planned for 2006 to 2010:
Accomplishing dump closure requires several actions, which are summarized in the discussion below. Semi-Annual Surface and Ground Water Monitoring: Ground water sampling and analysis will be conducted on a semi-annual basis using the on-site monitoring wells. If needed to monitor ground water quality, additional wells will be installed. Surface water samples will be collected from East Creek and West Creek on either side of the dump. Both surface and ground water samples will be analyzed for contaminants of concern. Construction of the Waste Transfer Station: The facility is expected to include a metal building about 60 feet by 60 feet in size, concrete slabs on the upper and lower levels, and concrete retaining walls. The Tribe will contact potential construction contractors, request bids, receive bids, select a contractor, and contract directly with a qualified contractor to build the waste transfer station according to the plans and specifications. Construction is expected to take place from summer 2007 through spring 2008. Closure and capping of the site will involve the following tasks: Consolidation/Closure Plan for Dump: A plan for the final closure of the dump will include drawings and cross sections, a timeline schedule, and cost estimates for waste consolidation, in-place closure, and long-term monitoring and maintenance of the site. This plan has already been drafted and will be updated as needed. Dump Waste Consolidation: Part of the closure in-place alternative involves consolidating the shallow waste on site to minimize the area and cost of cover construction. The results of the 1995 waste delineation and characterization (White Shield, 1995) will be used to develop plans for waste consolidation. Based on a 1995 topographic survey of the dump, the ravine appears to be a favorable location for consolidating waste on site, because it would involve moving the least amount of waste and most of that waste would be moved downhill. Based on the topographic data from White Shield (1995) and the relatively shallow slopes for a final consolidated landfill cover, there appeared at that time to be sufficient space to consolidate 20,000 to 25,000 cubic yards of waste in this valley. If the waste were consolidated in this manner, the total cover area could likely be reduced to less than 1.5 acres (Brown and Caldwell, 1999). The Tribe will contact potential contractors for the waste consolidation work, request bids, receive bids, select a contractor, and contract directly with a qualified contractor to perform the waste consolidation according to the waste consolidation plan. Once the waste is consolidated, the Tribe can proceed with final closure. Final closure includes engineering design, closure construction, design of a ground water monitoring system, closure construction, construction management, quality assurance testing, post-closure maintenance and monitoring, and legal, administrative, and financing costs. Post-Consolidation Survey and Mapping: A post-consolidation site survey will be necessary to establish the topography of the area to be covered after the waste consolidation is completed. The data obtained through this survey will be used to develop an updated topographic map of the consolidated waste area, which will be used as the base map for the landfill closure bid and construction documents. Engineering for In-Place Closure: This task will include performing the necessary permitting and engineering tasks associated with in-place closure of the dump. The Resources Conservation and Recovery Act requires that a hydrogeologic assessment be prepared for municipal solid waste landfill sites that are operated or closed in accordance with RCRA regulations. The purpose of the hydrogeologic assessment is to demonstrate (1) that the landfill is not polluting underlying ground water resources and (2) that the system of ground water monitoring wells has been designed to effectively monitor the site. For this project, the hydrogeologic data will be compiled into one document that will provide a basis for the design of a long-term ground water monitoring system. The closure design for the dump should be developed to meet the objectives of the Tribe and to comply with all applicable regulations, including those under RCRA. The design should conform to appropriate design standards acceptable to the Makah Tribal Council, the USEPA, the U.S. Army Corps of Engineers (USACE), the IHS, the BIA, and other government agencies with trust responsibilities to the Makah Tribe. The main elements of the engineering design for closure of the Warmhouse Beach Open Dump include:
RCRA requires that a post-closure plan be developed to demonstrate to regulatory agencies that the owner/operator has in place a plan that defines the landfill maintenance and monitoring activities during the 30-year post-closure monitoring period and demonstrates that the owner/operator has the necessary funds available to meet the costs of annual post-closure monitoring. The post-closure plan serves as a manual for performing post-closure monitoring activities. The plan will describe regular inspection and maintenance of the final cover, ground water monitoring system, landfill gas control system (if appropriate), and surface water drainage system. The post-closure plan will also include descriptions of the actual monitoring activities to be performed throughout the post-closure period, development of the ground water sampling and analysis plan, and future uses of the facility after the post-closure period is completed. Cost estimates will be prepared for post-closure activities. Construction Drawings and Specifications: The final design of the landfill closure will be based on the pre-design analysis contained in the agency-approved landfill closure plan. The purpose of this task is to develop contract drawings and specifications for the final closure system. These drawings and specifications must be suitable for a contractor to use in developing a bid price for the project and as guidance for constructing the closure system. In addition, the drawings and specifications must be suitable for use by the Tribe in monitoring the contractor's conformance to design specifications. In general, developing good, clear contract drawings and specifications can reduce a contractor's requests for change orders during project implementation and can minimize litigation resulting from disagreements between the contractor and the owner. Dump Closure Construction: This task involves construction of the closure system, including the cover system and any surface and ground water diversion or control systems. The Tribe will provide bid documents, attend a pre-bid conference to answer potential bidders' questions, conduct a site walk-through with potential bidders to familiarize them with the site, prepare any contract addenda as necessary during the bidding period, and provide technical clarification of the specifications as requested by the bidders. This task may also include the installation of additional ground water monitoring wells. If additional wells are needed, every attempt will be made to use the investigation wells as the long-term monitoring wells. During construction, a resident construction manager must be present on a daily basis to confirm that the landfill is being constructed in accordance with the approved plans and specifications. In addition, the resident construction manager should be able to address general technical questions about the contract or specifications, address change order issues, coordinate activities of the consultant, perform construction quality assurance testing, and review invoices for payment under the contract. Construction-phase engineering services to be performed for this task include attending the preconstruction conference with the Tribe and the selected contractor; providing construction consultation; reviewing change orders; conducting periodic site visits by consultant staff; conducting final inspection of the site to assess overall contractor conformance to specifications; and preparing record drawings and as-built drawings as required by regulatory agencies. Construction Quality Assurance (CQA) and Closure Certification: Regulatory agencies require construction quality assurance testing of liner materials to demonstrate that the required permeabilities are being obtained by the contractor and that geomembranes are seamed properly. It is generally recommended that CQA testing be provided by a qualified and neutral third-party contractor. The type of CQA testing required depends on the type of cover materials selected. CQA testing will be defined in the closure plan on a preliminary basis and then more strictly defined in the bid documents. Typical CQA tests for a landfill in a wet-weather area include air-leak testing and shear and peel tests on the geomembrane field seams. These tests are performed at regular intervals along the seam length and anywhere repairs are made. Contractors typically duplicate this testing for their own assurance. This task also includes certification by a registered engineer to document that the landfill was closed in accordance with the approved plans and specifications. A certification document is typically prepared to consolidate the construction information that justifies the closure certification. Certification documents may include a summary of responsibilities and lines of authority; manufacturer quality control data; seam test results; design change data; the construction punch list and as-built drawings; daily inspection reports; and construction photographs. Monitoring: RCRA requires 30 years of post-closure maintenance and monitoring at a landfill. The wells used for the hydrogeological investigation will also be used as long-term monitoring wells, if practical. If new wells are needed based on the findings of the pre-construction hydrogeological investigation, they will be located, designed, drilled, and installed to monitor ground water quality. Ground water sampling and analysis will be conducted regularly. In addition, surface water will be collected and analyzed regularly, and the landfill gas control system will also be monitored. A maintenance and monitoring plan will be developed. The plan will describe the monitoring procedures, outline monitoring frequency, and provide instructions for inspection and maintenance of the final cover, ground water monitoring system, surface water drainage system, and gas control system. Additional Information:
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![[ Waste at Warmhouse Beach Open Dump ]](Site4_waste.jpg "Waste at Warmhouse Beach Open Dump")
![[ Creek discharging to Warmhouse Beach ]](Site4_creek.jpg "Creek discharging to Warmhouse Beach")
![[ Waste stream audit ]](Site4_wastechar.jpg "Waste stream audit")
![[ Groundwater sampling at Site 4 ]](Site4_gw.jpg "Groundwater sampling at Site 4")
![[ Sampling locations, 2004 SI ]](tnSite4_SI_Fig3.jpg "Sampling locations, 2004 SI")
![[ Sampling locations, 2006 annual sampling ]](tnSite4_2006.jpg "Sampling locations, 2006 annual sampling")