The Smokey Mountain Smelters Site was originally a series of fertilizer and agricultural chemical companies which operated from the 1920s to the 1960s. Smokey Mountain Smelters (SMS), also known as Rotary Furnace, Inc., operated at the Site from 1979 to 1994 and has been inactive since that time. The facility was a secondary aluminum smelting operation. The process involved the melting of scrap aluminum and aluminum dross (a waste by-product of primary and secondary aluminum smelting) and casting the molten aluminum ingots. Raw materials at the facility primarily consisted of scrap aluminum and aluminum dross. Waste material from the SMS operation was primarily saltcake, a residue from dross smelting with high salt and low metal content. Other waste materials included baghouse dust and discarded aluminum dross. Much of the Site is covered in a waste pile consisting of saltcake and aluminum dross that was dumped directly on the land surface without a liner or drainage controls.
In 1983, Tennessee DHE Division of Solid Waste Management issued a notice to SMS with the conclusion that the Site was “unsuitable for use as an industrial landfill;” however, landfilling on-site continued to occur for several years afterward. In addition, the Knox County Department for Air Pollution Control (KCDAPC) documented numerous citizen complaints regarding excessive air emissions from the Site and cited SMS for several air quality violations in the 1980s.
The total SMS Site is approximately 13 acres in size and includes one large industrial process building, a small lagoon, a large outside saltcake waste pile, and three mid-sized indoor dross waste piles. The process building is approximately 100 feet wide by 300 feet long, and 50 feet high; it houses some equipment and three 900 cubic-yard (each) piles of aluminum dross. Portions of the north and east walls of the building have collapsed. The spring-fed lagoon measures approximately 25 feet wide by 100 feet long and is located to the southeast of the process building. The saltcake waste pile is approximately 50,500 cubic yards in size and covers an area of about 4 acres on the south side of the process building. Surface runoff from the Site generally flows to the southwest. Leachate and surface runoff discharges to an unnamed tributary stream, reaching Flenniken Branch and eventually the Tennessee River.
Multiple sampling events between 1997 and 2006 have been conducted at the Site to characterize the composition and contaminant concentrations in the waste piles, the raw material piles, the on-site lagoon, leachate to the unnamed tributary, and downstream impacts to the unnamed tributary and Flenniken Branch. Dross and saltcake are exothermically water-reactive materials that release heat and ammonia gas, and leach aluminum, ammonia, chlorides, and other contaminants.
In 1997, the Tennessee DSF collected surface water and waste samples at SMS. Elevated levels of ammonia, arsenic, lead, and aluminum were found in surface waters at the Site. Elevated levels of aluminum, PAHs, heptachlor, heptachlor epoxide and ammonia were found in the on-site waste pile. Headspace air samples over the waste pile measured elevated concentrations of ammonia. DSF collected additional samples from the Site in 2001, 2003, and 2004 to monitor ongoing surface water conditions. Analysis of these later samples showed that contaminant concentrations in surface waters leaving the Site had increased for arsenic, lead, and aluminum. Elevated levels of chlorides were found in surface waters leaving the Site that were significantly above background levels. Elevated concentrations of ammonia, chlorides, and pH were found along the entire length of the unnamed tributary to the Flenniken Branch downstream of the Site.
A residential apartment community within 75 feet of the Site houses approximately 560 residents. During a 2008 Site visit the EPA OSC observed that access controls were not adequate to keep trespassers out of the property. Holes had been cut in the site fence and a path leads from the Site to the nearby apartment complex. A time critical removal action was initiated to provide stronger security measures in order to keep trespassers away from the water-reactive dross material, and collect additional data to determine if further waste removal or treatment action is necessary.