Region 7 Fact Sheet ^ \ ISBJ Iowa Kansas Missouri Nebraska Nine Tribal Nations March 2016 West Lake Landfill Superfund Site Bridgeton, Missouri INTRODUCTION This fact sheet provides a historical overview of the West Lake Landfill Superfund Site, its current state, and work being done to protect the public from potential health risks associated with the site. BACKGROUND The West Lake Landfill Superfund Site is located in Bridgeton, Mo. The site consists of several inactive landfills, including the West Lake Landfill and the Bridgeton Landfill. Originally used for agriculture, the land became a limestone quarrying and crushing oper- ation in 1939. Beginning in the early 1950s, portions of the quarried areas and adjacent areas were used to dispose of municipal refuse, industrial solid wastes, and construction/demolition debris. In 1973, around 8,700 tons of leached barium sulfate from the Manhattan Pro- ject, a World War II nuclear bomb development pro- gram, was mixed with approximately 38,000 tons of soil and used to cover trash being dumped during daily op- erations. In 1990 the U.S. Environmental Protection Agency listed the site on the National Priorities List under the Comprehensive Environmental, Response, Compensa- tion and Liability Act of 1980 (Superfund law). The Agency listed the entire 200-acre facility and has since divided it into two areas referred to as Operable Units. Operable Unit 1 (OU-1) contains radiologically- impacted material (RIM). The adjacent Bridgeton Landfill, which is a part of OU- 2, is part of the Superfund Site, but remains under the regulatory authority and oversight of the Missouri De- partment of Natural Resources. COMMUNITY HEALTH Since 1990, EPA has overseen numerous air, soil and groundwater tests related to the West Lake Landfill. The scientific data demonstrates that the wastes at the landfill do not currently pose an off-site health risk to the surrounding community. The recent Agency for Toxic Substances and Disease Registry's (ATSDR) health consultation confirmed previous EPA and MDNR assessments that show groundwater, air, and soil data do not indicate a current health risk to communities sur- rounding the West Lake Landfill. In its health consultation, ATSDR expressed concern regarding the health impacts of radon gas to any past, current, and future on-site workers of the landfill. If landfill surface disturbances occurred at certain loca- tions in OU-1, dust particles containing uranium and thorium decay products could have been released to the atmosphere. In December 2015, EPA ordered the responsible parties to take steps to cover those areas at the landfill where radiological material was at or near the surface. This cover will alleviate the concerns re- garding landfill surface disturbances. Additionally, there have been a number of significant assessments to determine if radiological material has migrated offsite, into the surrounding community; tests included off-site air and soil sampling, as well as groundwater monitoring. The Missouri Department of Natural Resources regularly publishes air monitoring results and the Missouri Department of Health and Senior Services continues to review the data collected for any health concerns. There is no known exposure pathway to contaminated groundwater beneath the site. Without a pathway, the water will not harm people's health. The water currently flows away from residential areas and is not being used as a public water supply. If you have health-related questions or concerns, please talk with your physician, or contact Lieutenant Commander Erin Evans, U.S. Public Health Service, at isb5@cdc.gov. THE CONTAMINATION In 1990 the EPA listed the site on the National Priorities List. The agency listed the entirety of the 200-acre West Lake Landfill due to the presence of radioactive waste in an area now known as Operable Unit 1 (OU- 1). The portion of the landfill that does not contain radi- ological material is now known as Operable Unit 2 (OU- 2). The adjacent Bridgeton Landfill remains under the oversight of the Missouri Department of Natural Re- sources. Within OU-1, radioactive material has been found in two areas. At the time of the 2000 Remedial Investiga- tion, Area 1 encompassed approximately 10 acres southeast of the main entrance road to the West Lake Landfill property. Area 2 encompassed approximately 30 acres along the northern boundary of the West Lake ------- Landfill property. Additional investigations performed in Area 1 throughout 2014 and 2015 have improved our understanding oftheOU-1 boundary. GOING FORWARD Isolation System In December 2010, Bridgeton Landfill LLC notified Mis- souri Department of Natural Resources (MDNR) that it found elevated temperatures in its south quarry. The company and MDNR eventually determined this to be an underground smoldering event. A subsurface smol- dering event (SSE) is a high-temperature, self- sustaining (without the need for oxygen), chemical re- action that is consuming the buried waste (accelerating decomposition). The most recent testing data indicate the SSE has not migrated past the area referred to as the "neck" which lies between the Bridgeton Landfill North and South Quarries. A series of temperature monitoring probes and gas extraction wells, in addition to visual observa- tion and other methods, provide data to monitor the SSE. On Dec. 31, 2015, EPA announced its decision to pro- ceed with the installation of an isolation barrier. The decision calls for the installation of additional engineer- ing controls, such as cooling loops, to prevent potential impacts that could result if a SSE were to come into contact with radioactive materials contained in the West Lake Landfill. EPA will continue to work closely with MDNR with ex- pert support from the Army Corps of Engineers. EPA will release additional information, such as location of the barrier, once plans are finalized. Surface Fire Prevention EPA issued a Unilateral Administrative Order (UAO) on December 9, 2015, for a time-critical removal action to reduce or prevent the risk of surface fires in areas where RIM is located at or near the surface. A UAO is an enforceable order requiring the completion of speci- fied actions. A surface fire could potentially lead to a release of radi- onuclides near areas where radiologically impacted materials are located at or near the surface, creating an on-site hazard for workers at the site. To mitigate this risk, the UAO requires the Potentially Responsible Par- ties (PRPs) to: -Implement engineering measures to mitigate the risk of a surface fire within the boundary of the West Lake Landfill site coming in contact with radiologically im- pacted material at or near the surface, and -Develop an incident management plan that will be used to coordinate with local emergency responders. 2016. Long-Term Remedy The results of additional site characterization and as- sessments will be used in a revised evaluation of vari- ous remedial options, including the 2008 selected rem- edy, partial excavation, and full excavation. By the end of 2016, EPA will present its proposed decision on whether or not to make changes to the 2008 Record of Decision to the community with an opportunity to com- ment. After the public comment period closes, EPA will release its final remedy decision. ADDITIONAL INFORMATION Technical documents, maps, and other site related in- formation is available online at: https://vwvw3.epa.gov/ reaionOy/cleanup/west lake landfill. Concerned residents may also contact Ben Washburn, EPA Region 7 Community Involvement Coordinator, at (913) 551-7364 or washbyrn.ben@epa.gov. This work is expected to be completed in late spring of ------- |