A flaw in construction led to the Gatlinburg (Tenn.) Wastewater Treatment Plant basin wall collapse that killed two workers last spring, according to report cited by the Knoxville News Sentinel.
The report from Mohammad Ayub from the OSHA Office of Engineering said that while the basin’s design was adequate, “a deficiency in concrete wall construction" led to the collapse. “Walls were cast in a manner that produced a cold joint between the east wall, which fell, and the three intersecting walls," Ayub wrote in his summary. Those walls were critical to the east wall’s integrity.
"What the engineer called a ‘cold smooth joint’ led to leakage of acidic waste water across the joint, and ‘as a result, corroded the rebar splice couplers over a number of years,’” the newspaper reported. The failure occurred gradually over time.
The basin contained 1.3 million gallons of wastewater and was 85 percent full when the wall gave way. The workers who died were in a flow-control building when the wall collapsed on top of it, according to the report. No safety violations were found during the investigation. Veolia Water North America employees John Eslinger, 53, and Don Storey, 44, died in the collapse. The workers were adjusting valves after a night of heavy rain when the basin wall collapsed and crushed them, according to Veolia officials.
The full story is at http://m.knoxnews.com/news/2011/oct/27/deficient-wall-construction-cited-in-gatlinburg/.
