EPA Proposes Site to National Priorities List, Washington County Lead District, Potosi Site, Washington County, Missouri
The U.S. Environmental Protection Agency (EPA) is proposing the Washington County Lead District--Potosi Site to the National Priorities List or NPL. The NPL is a published list of hazardous waste sites in the country that are eligible for extensive, long-term cleanup action under the Superfund program. EPA is asking for comments on the proposal.
Washington County is part of Missouri's Old Lead Belt, where lead mining has occurred for several hundred years. This area is also part of the barite mining district of Missouri. The county has hosted over 1,000 lead and barite mining, milling and smelting sites. Mining activities in Washington County have contributed to elevated levels of lead in soil and ground water in this area.
EPA is conducting investigations and cleanup work at the site under the Superfund program. Congress established Superfund in 1980 in response to growing concerns over human health and environmental risks posed by hazardous sites. After a Superfund site is discovered, cleanup can fall under two programs: removal and remedial. Removal actions address immediate threats to human health and the environment posed by contamination. Remedial actions address sites that require extensive and potentially long-term cleanup. Under the Superfund program, a site may qualify for placement on the NPL. The NPL is intended primarily to guide EPA in determining which sites warrant further investigation and cleanup. For a site to be included on the NPL, it has to score sufficiently on the Hazard Ranking System (HRS). The HRS evaluates exposure pathways and the potential risk to human health and the environment. Those sites that score high enough on the HRS are eligible for the NPL. A site that is listed on the NPL qualifies to be financed by Superfund's Trust Fund. If a responsible party is not identified, a site cannot undergo a remedial cleanup unless it is listed on the NPL.
The Washington County Lead District--Potosi Site is being proposed to the NPL due to the potential risks associated with the levels of lead detected in soils and ground water at this site. Missouri supports this proposal.
COMPLETED SITE ACTIVITIES
Under the removal program, EPA has collected soil and water samples from 1,571 properties located in the Potosi area. To date, 158 properties with lead-contaminated soil above 1,200 parts per million (ppm) have been identified. At this level, EPA prioritizes properties for cleanup as time-critical removals. By the end of August, EPA had excavated and replaced contaminated soil at 69 of these properties.
EPA has also identified 138 private residential wells with lead above 15 parts per billion (ppb). Currently, 120 of these residents have agreed to accept bottled water from EPA for drinking and cooking purposes. An additional 539 properties have been identified with lead soil contamination in the range of 400 ppm to 1,199 ppm. These properties will be addressed through remedial action.
FUTURE SITE ACTIONS
A remedial investigation and feasibility study will be performed to fully define the nature and extent of contamination, followed by an evaluation of alternatives to clean up the contamination. EPA will ultimately present this information to the community and ask for comments on EPA's proposed actions before making decisions about site cleanup.
TECHNICAL ASSISTANCE GRANT
EPA wants to help affected communities understand the technical information related to a site. EPA's Technical Assistance Grant Program provides up to $50,000 for a qualified citizens group to hire independent technical advisors. The advisors can help citizens interpret technical data, understand site hazards, and become more knowledgeable about the different technologies used to clean up sites.
EPA is requesting comments until November 19, 2007 on the proposal to add this site to the NPL. Comments should be mailed or e-mailed to:
U.S. Environmental Protection Agency
CERCLA Docket Office
Mail Code 5305T
1200 Pennsylvania Avenue, NW
Washington, DC 20460
ATTN Docket ID No. EPA-HQ-SFUND-2007-0688
If you have questions about this proposal or want additional information about applying for a Technical Assistance Grant, please contact:
U.S. EPA Region 901 N. Fifth St.
Kansas City, KS 66101
Phone: 913-551-7003 or Toll Free: 1-800-223-0425