Starting a century ago, the 13-acre property on Maryville Pike was home to a series of fertilizer and agricultural chemical companies. Smokey Mountain Smelters, also called Rotary Furnace Inc., melted scrap aluminum and cast it into ingots there between 1979 and 1994. When the company shut down, huge exposed piles of waste products remained on the ground and in a tributary of Flenniken Branch.
The runoff contaminated the creek that flows through nearby I.C. King Park and eventually drains to the Tennessee River, a drinking water source and recreation destination.
Sedimentation from another disturbed piece of land in South Knoxville has already threatened to smother the beleaguered creek, according to the state, as referenced in a Hellbender Press report last year.
The EPA added Smokey Mountain Smelters to the Superfund list in 2010. Surface water, ground water, soil and air samples at the site showed elevated levels of various heavy metals such as arsenic and lead as well as ammonia, chlorides, and chemicals like polycyclic aromatic hydrocarbons (PAHs), all of which can harm human health.
Residents of the adjacent Montgomery Village public housing complex often took shortcuts across the property, and homeless people had been in the buildings. So EPA conducted a “short-term” cleanup to eliminate surface contamination and the immediate risk to the public. It demolished the collapsing buildings and removed debris. The rest of the waste was covered temporarily under a clay cap. But sporadic tests showed pollutants still seeping into the groundwater.
In 2015, the agency decided on a plan for more complete cleanup, projected to cost $3.7 million. Before proceeding, the EPA tried to pursue those who made the mess.
“We haven’t been doing nothing,” Kestle said. “We’ve been trying to get the responsible parties to pay for the cleanup.”
Smokey Mountain Smelters owner Daniel Johnson had died, however, and his heirs excluded the property in the estate they inherited, Kestle said. “That’s how it became an orphan site.”
EPA and U.S. Department of Justice lawyers have since concluded that because of the array of industrial activities on the property over the past century, it would be hard to hold any single owner or former operator liable, Kestle said.
That leaves taxpayers footing the cleanup bill. But it’s expected to be among the easiest and cheapest to finish in the Southeast, Kestle said. “We did a pretty good job on the initial response work,” he said. “That’s why this was relatively low priority until the money came along for infrastructure improvement.”
Rejecting more expensive options that would have included extensive soil removal, the EPA plans to install a higher-quality cover system with a gas collection layer, a geosynthetic clay liner, a high-density plastic drainage liner, 18 inches of protective soil and another six inches of topsoil. Water treatment chemicals will also be injected into the water table, which will be monitored using wells.
Reviews will be conducted every five years to evaluate whether the treatment is effective at protecting human health and the environment, the plan states.
The new cap will take a year or less to construct, Kestle said. The groundwater treatment will take longer, although it can continue without delaying redevelopment.
The buried waste includes “salt cake,” which is highly corrosive and dissolves easily in water. The contaminants it contains can filter through porous underground limestone to the ground-water table, which is as shallow as 35 feet, according to federal documents by EPA and the Agency for Toxic Substances and Disease Registry. Surrounding residents have access to public drinking water.
Although surface water contamination is unlikely to have persisted, it hasn’t been monitored to find out for sure, Kestle said. (He noted that there are already posted warnings against eating fish caught at I.C. King Park or from the Tennessee River, because of pollution unrelated to Smokey Mountain Smelters.) The 2015 EPA assessment concluded that the former industrial property posed no substantial harm to the surrounding environment.
Kestle said some contamination could remain in the creek sediment, but metals break down over time. “We’re still concerned about it and want to make sure no more contamination leaves the site,” he said.
“But as far as digging up the creek to remove it, that would probably cause more damage than good.”