The site is located in a heavily mined region of eastern Missouri known as the Washington County Lead District. The site includes residential areas within and around the towns of Caledonia, Irondale, Belgrade, and Hopewell, and is only a portion of the larger Washington County Lead Mining District.
Lead mining in southeast Missouri began around 1720, and is still mined in the Viburnum Trend, which includes part of Washington County (Doe Run’s Viburnum Mine 29). The Missouri Department of Natural Resources has developed a database of known mining occurrences in the State of Missouri called Incidents of Mines, Occurrences, and Prospects. Currently there are over 1,000 entries in the database for Washington County.
Toward the end of the American Civil War, lead deposits in Washington County ran low and the industry declined. It was soon replaced by the surface mining of barite (barium sulfate), which was used in rubber, paint, soap, drilling fluids, and medical products. Many lead mines were over-mined for the barite, which was also associated with galena (lead sulfide). The barite was separated from the clay initially by hand washing and then by mechanical barite washing plants that were introduced into the area in the 1920s. In 1941, Missouri accounted for 40 percent of the United States barite production.
In June 2008, EPA began a removal assessment that included soil and groundwater sampling in the Furnace Creek area. During this sampling event, EPA contractors screened the soil at 428 residences and sampled 207 private drinking water wells. The results of this sampling effort revealed the following information.
Properties with soil levels greater than 400 ppm 145
Properties with soil levels greater than 1,200 ppm 33
The Superfund Technical Assessment and Response Team (START) contractor continues to sample residential properties and child high-use areas at the site. The following is a summary of the results of sampling to date.
Clean Properties: 795
Non-Time Critical Properties: 258
Time-Critical Properties: 135
Drinking Water Wells Sampled 922
Wells exceeding 15 ppb lead 11
To date, the Emergency and Rapid Response Services (ERRS) contractor has completed excavation and backfilling of 110 properties with an estimated volume of 18,088 cubic yards removed. The ERRS contractor is also providing alternative drinking water to 4 property owners whose wells are contaminated with lead.
On or about October 26, 2009, EPA mailed out approximately 604 letters to homeowners that had previously refused access or did not answer previous requests to sample. To date, as a result of this mailing, EPA received permission to sample from an additional 76 property owners.
The Emergency and Rapid Response Services contractor will continue excavation of time-critical properties.
The sampling and cleanup efforts will continue.
None.
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