West Lake Landfill
The West Lake Landfill Superfund Site is located at 13570 St. Charles Rock Road in Bridgeton, Missouri, and contains several former waste disposal areas, including the Bridgeton Sanitary Landfill. The 200-acre site sits within the Earth City Industrial Park and is surrounded by commercial, industrial, residential and agricultural land on a levee-protected edge of the Missouri River floodplain.
Past practices at the site include mining limestone and landfilling industrial wastes, demolition debris and municipal solid waste. In 1973, soils mixed with uranium ore processing residues were transported to the site and used for landfilling operations, radiologically contaminating at least two of the former disposal areas of the site.
In 1990, the U.S. Environmental Protection Agency (EPA) listed West Lake Landfill on the National Priorities List making it a Superfund site. Each of the former waste disposal areas have contamination characteristics unique to that area. In order to address contamination more effectively, EPA divided the site into three distinct operable units (OUs).
- Operable Unit-1 (OU-1): Along with contamination typically encountered in landfills, OU-1 is also contaminated with radiological material and other material from the uranium ore processing residues and soils from the Hazelwood Interim Storage Site. OU-1 includes two designated radiologically impacted former waste disposal areas (Area 1 and Area 2), and property adjacent to Area 2 (Buffer Zone and Crossroads Lot 2A2) resulting from migration of radiologically impacted material (RIM) from Area 2.
- Operable Unit-2 (OU-2): This unit consists of former waste disposal areas that are not known to be impacted by radiological materials. These disposal areas and expected contaminants were presumed typical for solid waste landfills.
- Operable Unit-3 (OU-3): OU-3 is intended to address site wide groundwater contamination.
Missouri Department of Natural Resources’ Role
EPA is the lead regulatory authority over the Superfund site; therefore, the department’s federal facilities section provides a support and assistance role for this site.
Federal facilities section staff provide technical review on decision documents, work plans, designs, investigations, and reports. Depending on the nature of the activity and content of the documents, the section may coordinate with other programs and state entities to respond appropriately.
Periodically, staff visit the site to observe and document site status, activities, environmental monitoring and investigations.
Occasionally, staff also perform independent investigations and sampling in the vicinity of West Lake Landfill.
Site Status for OU-1
Comprehensive, Environmental Response, Compensation, and Liability Act (CERCLA) Superfund Actions Since EPA’s 2018 Record of Decision Amendment
On May 6, 2019, EPA and the responsible parties agreed to add remedial design work to the existing settlement agreement. A consent decree and settlement agreement for implementation and construction (remedial action) is in negotiation.
Remedial design covers pre-construction investigation and planning activities in preparation for remedial action at the site.
Monitoring and safety planning are essential components of remedial design that evolve as the project moves from planning to construction.
Design monitoring starts with documenting baseline site conditions, so when field activities begin, any changes that occur due to field work can be recognized and appropriate actions taken. The monitoring plan is expected to become more complex when remedial action begins. The responsible parties submitted a second draft Site Management Plan, West Lake Landfill Superfund Site Operable Unit 1 to EPA.
Certain monitoring acivities, such as air monitoring and stormwater monitoring were drafted separately from the management plan document and have been approved by EPA.
Design safety planning includes documents designed to keep workers safe in the field, and are typically referred to as health and safety plans. Additional safety planning is developed to protect site personnel and the public during potential emergency events. For OU-1, this planning document is referred to as the Emergency Response Plan. The responsible parties currently have an EPA approved Emergency Response Plan for OU-1.
- Responsible parties' RD Health and Safety Plan
- Responsible parties' final draft Emergency Response Plan; EPA approval with comments
The remedial design work plan develops the construction and implementation plan to ensure the remedial action complies with the record of decision amendment, and protects health and the environment. There are a number of approaches for remedial design, but they generally follow similar phased patterns. The phases for design of the OU-1 remedy are outlined in Section 6 of EPA’s statement of work. Based on the schedule, the responsible parties should be past the 30 percent design development stage.
Preliminary Remedial Design: These documents are intended to describe in detail how the design phase will be implemented and where information will be presented leading up to the final design. EPA approved the work plan and design criteria report with comments.
Preliminary Excavation Plan: The preliminary excavation plan document is intended to describe how total activity will be calculated to show conformance with requirements of the record of decision. When final, the excavation plan should describe the boundaries of the planned excavation.
- The responsible parties submitted a draft preliminary excavation plan; and EPA approved the document with conditions. MoDNR provided comments on the plan.
Design Investigation Work Plan: The design investigation work plan identifies and addresses any data gaps that the engineering contractor needs to answer in order to design the remedy and ensure the requirements of the ROD amendment are met. Since this work plan involves sampling and investigative activity, other documents are included with the plan to show that collected data will meet the goals of investigations to be performed.
- Final draft Design Investigation Work Plan, Field Sampling Plan, Quality Assurance Plan, Data Management Plan, EPA approval with modifications, MoDNR comments
- Second draft Design Investigation Work Plan, Field Sampling Plan, Quality Assurance Plan, Data Management Plan, EPA comments, MoDNR comments
- First draft Design Investigation Work Plan, Field Sampling Plan, Quality Assurance Plan, Data Management Plan; EPA comments part 1; EPA comments part 2; and MoDNR comments
CERCLA Superfund Actions between EPA’s 2008 Record of Decision and 2018 Record of Decision Amendment
EPA signed a record of decision for OU-1 in May 2008 that required the responsible parties to, among other activities, construct a modified solid waste landfill cover to contain the radiological contamination in place. This solution (remedy) was selected with the intent to protect humans or other organisms from coming into contact with, or being harmed by, the contamination. Prior to design completion, EPA ordered the responsible parties to perform additional work that is reflected in the following documents:
- EPA approved the supplemental feasibility study on Dec. 28, 2011, which compared the selected remedy against additional alternatives.
- The investigation addendum report incorporated recent sampling data into a revised model of radiological contamination and updated the analysis of risk to health and the environment (risk assessment).
- The final feasibility study report brought the new information together to compare all potential remedies against the nine criteria required by federal regulation, as described in the Code of Federal Regulations, 40 CFR 300.430(e)(9)(iii).
Based on the new information, EPA determined an amendment to the original remedy was needed in order to be protective of health and the environment. EPA issued the proposed amendment on Feb. 1, 2018, and solicited the public to comment on the proposed plan from Feb. 6 through April 23, 2018. EPA issued the final decision on Sept. 27, 2018 along with a fact sheet explaining the amended remedy. MoDNR provided public technical comments on the proposed plan, and position on the selected remedy.
Site Status for OU-2
In July 2008, EPA signed a record of decision for OU-2 selecting various remedies for three former waste disposal areas including Bridgeton Sanitary Landfill. EPA has retained regulatory authority for the area identified as the Inactive Sanitary Landfill in OU-2, and remedial design is expected to be completed concurrent with design of the remedy for the adjacent OU-1, Area 2.
EPA deferred the other two former waste disposal areas in OU-2; including the Former Active (Bridgeton) Sanitary Landfill and the Closed Demolition Landfill, to state regulatory authority. The department’s waste management program oversees closure and post-closure of these units. Additional information is available on MoDNR’s Bridgeton Landfill page.
- The responsible party's final remedial design work plan for the Inactive Sanitary Landfill
- The responsible party has submitted a third draft remedial design work plan for the Inactive Sanitary Landfill, EPA approval with modifications
- Responsible party's second revised draft remedial design work plan for the Inactive Sanitary Landfill; EPA comments; MoDNR comments
- Responsible party's revised draft Remedial Design Work Plan for the Inactive Sanitary Landfill; EPA comments; MoDNR comments
Pre-design and investigative documents developed from the approved work plan:
- Existing conditions report
- Slope stability and western waste limit
- Soil cover evaluation
- Waste separation between Inactive and Bridgeton Landfills, EPA comments
Monitoring documents developed from the approved work plan:
Site Status for OU-3
On Feb. 6, 2019 EPA and the responsible parties finalized an administrative settlement agreement and order on consent for investigation and remedial options for site wide groundwater. The responsible parties have drafted a work plan to perform the required work.
- Responsible parties' fourth draft remedial investigation and feasibility study work plan
- Responsible parties' third draft remedial investigation and feasibility study work plan, EPA comments
- The responsible parties have submitted a second draft remedial investigation and feasibility study work plan; EPA disapproved the submittal. MoDNR provided comments to EPA.
- Responsible parties’ first draft remedial investigation and feasibility study work plan; EPA comments; MoDNR comments
Interim Site Actions
OU-1 Non-Combustible Cover Time-Critical Removal Action
In a unilateral administrative order dated Dec. 9, 2015, EPA ordered the responsible parties to place non-combustible cover over portions of OU-1 where radiologically impacted material is located at or near the surface. Components of the order in addition to placement of non-combustible cover include:
- Testing and surface surveys to confirm surficial RIM was covered.
- Determination of potential radiological risk from combustion of remaining vegetation in OU-1.
- Maintenance of the non-combustible cover.
- Site wide incident management plan for responding to incidents affecting OU-1.
- Action documents and reporting requirements.
While placing non-combustible cover over remaining RIM on steep slopes in Area 2, 167 tires were found lining one of the slopes. The responsible parties developed a cleaning, screening, and disposal plan; EPA approved the plan prior to removal of the tires from the site.
Isolation Barrier System and North Quarry Time-Critical Removal Action
On May 13, 2013 Bridgeton Landfill entered into an Agreed Order with the State of Missouri to address the subsurface smoldering event. The agreed order included a phased sampling program in Bridgeton Landfill near Area 1 to identify potential locations for installation of a barrier between radiologically impacted material and the existing smoldering event. EPA later took the lead regulatory role in the investigation, and approved the results in April 2017 that expanded the previously defined boundaries of OU-1 Area 1.
The responsible parties also developed and continue to implement a baseline air-monitoring program as part of EPA’s administrative settlement agreement and order on consent dated April 16, 2014.
In EPA’s follow-on administrative settlement agreement and order on consent dated April 28, 2016, the responsible parties implemented engineering controls within portions of the Bridgeton Landfill to mitigate potential impacts to OU-1 Area 1 of subsurface exothermic events originating in Bridgeton Landfill. These controls include:
- Inert gas injection plan, and criteria for implementation.
- Installation of ethylene vinyl alcohol (EVOH) cover over the North Quarry.
- Installation of a heat extraction system in the neck area of Bridgeton Landfill based on the work plan document that was conditionally approved by the department on Dec. 4, 2015.
- Two sulfur dioxide ambient air monitors and monitoring for one year.
- Installation of a system of temperature monitoring probes in the north quarry area of Bridgeton Landfill.
- Action documents and reporting requirements.
The responsible parties continue to operate and monitor the systems.
West Lake Landfill Vicinity Radiological Surveys
May 16, 2013 – Department staff conducted radiological surveys and collected deposition dust samples near the site, using odor as a wind direction indicator. The upwind and downwind readings were compared for differences in radiological readings.
- Department of Health and Senior Services Bridgeton Sanitary Landfill Final Radiological Air Sampling (June 2013)
November 2015 through April 2016 – MoDNR staff conducted radiological surveying and sampling in the vicinity of West Lake Landfill. The report on the investigation was released in two phases. The first interim report, released Jan. 25, 2016, described the investigation and presented immediately available data. The second final report, released April 1, 2016, supplemented the interim report with laboratory sample results and investigation conclusions.
- Department of Natural Resources -- West Lake Interim Vicinity Report - Radiological Survey and Sampling - Nov. 4-6, 2015
- Department of Natural Resources -- West Lake Landfill Final Vicinity Report - Radiological Survey and Sampling - Nov. 4-6, 2015
- Missouri Department of Health and Senior Services Bridgeton/West Lake Landfill Radiological sampling (Interim Report) – Nov. 4-5, 2015
- Missouri Department of Health and Senior Services Bridgeton/West Lake Landfill Radiological Sampling Final Report – Nov. 4-5, 2015
State Regulated Areas and Permits
Waste Management Program – Learn more about the department's Waste Management Program’s work at the Bridgeton Sanitary Landfill (OU-2)
Air Pollution Control Program – Operating Permit for Bridgeton Landfill, LLC
Water Protection Program – Stormwater Permit for Bridgeton Landfill, LLC
- EPA Community Involvement Plan (Update) West Lake Landfill Superfund Site, Bridgeton, Missouri, U.S. Environmental Protection Agency, October 2011.
- West Lake Community Advisory Group (CAG)/ Technical Assistance Services for Communities (TASC)
EPA maintains electronic files for the administrative record and hard copies at the address provided below. The administrative record includes all documents and data used and produced to develop cleanup alternatives and support the remedy for the site. The record also includes the community involvement plan, fact sheets, site updates, and general information about the Superfund program.
The administrative record is available at:
Bridgeton Trails Branch of the St. Louis County Library
3455 McKelvey Road
Bridgeton, MO 63044
Hours: Monday through Thursday 9 a.m. to 9 p.m., Friday and Saturday 9 a.m. to 5 p.m. The library is closed on Sundays.