COPPER BASIN MINING DISTRICT, OPERABLE UNIT
COPPERHILL, POLK COUNTY, TENNESSEE
BACKGROUND AND STATEMENT OF ISSUES
The Copper Basin Mining District Site is located in Polk County, Tennessee. Commercial mining operations began in the region in the mid 1800s. A large complex mining and production facility operated in the basin for years and included mining, milling, floatation, roasting, smelting, and producing bulk chemicals (primarily sulfuric acid).
The subject area covers 30 square miles and includes the now defunct Tennessee Chemical Company (TCC) and other areas that have been impacted by mining activities. The TCC ceased mining activities in the basin in 1987 and declared bankruptcy in 1989. Much of the land formerly owned by TCC was auctioned off and is now in private hands.
The EPA divided the site into six operable units. This health consultation will address contamination in Operable Unit 2. This operable unit includes the Oconee River from McCaysville, Georgia, to the Oconee No. 3 dam. The portion of the Oconee River within the Copper Basin Mining District site has been severely impacted by past mining activities. Surface water runoff has eroded large amounts of surface soil from the basin and deposited it in the river. Davis Mill Creek and North Potato Creek continue to discharge water and sediment containing elevated concentrations of metals into the Oconee River.
In 1997, PRC Environmental Management, Inc., a contractor for EPA, conducted environmental sampling at the site. This consultation will focus on the results of this environmental sampling, since these data provide the most recent characterization of environmental contamination at the site.
Samples of sediment and surface water from the Oconee River were collected and analyzed for metals and organic chemicals. Elevated levels of site-related metals (copper, lead, manganese, and zinc) were detected. Contaminant concentrations were highest at the discharge points of Davis Mill and North Potato Creeks and decreased substantially upon dilution into the Oconee River.
The maximum concentrations of metals detected in sediment and surface water from the Oconee River are presented in the following table. The surface water samples collected at the mouth of Davis Mill and North Potato Creeks are not included in this table since they are not representative of water from the several miles of the Oconee River in Operable Unit 2.
Table 1: Maximum concentrations of contaminants in environmental
media from the Oconee River in Operable Unit 2(a)
|sediment||1400 J||160 J||760||2300|
(a) sediment - parts per million (ppm)
surface water - parts per billion (ppb)
J - estimated value