Faulty construction at the Gatlinburg, TN, Wastewater Treatment plant resulted in a wall collapsing killing two workers.
The design of the walls of a basin at the plant were in such a way that leakage of acidic waste across a joint corroded metal couplers over a long period of time, according to the Tennessee Occupational Safety and Health Administration (TOSHA).
Plant operators John Eslinger and Donald Storey died April 5 when a concrete wall fell onto the control building where they were working. The collapse sent about 850,000 gallons of untreated sewage into the Little Pigeon River.
Construction of the wall that collapsed during a period of heavy rain occurred in such a way it produced a “cold joint.” The construction allowed acidic effluent to corrode reinforcing bar splice couplers, the report said. The couplers probably did not all fail in the collapse, but gave way over a number of years, the report said. Construction of the equalization basin, where the failure occurred, finished in 1996.
Inspectors also found the contractor used splicing couplers instead of the specified dowels. TOSHA, however, concluded the switch was not, in itself, a cause of the collapse, but the change did accelerate deterioration.
The agency said the design of the basin was such that intersecting walls within it would help support the outside wall, which failed.
The agency concluded there were no violations of standards in design or construction of the plant and there will be no citations, according to the summary report.