Since June 2012, the 0.995 mgd Hanceville (Alabama) Wastewater Treatment Plant had met all NPDES discharge permit limits set by the state Department of Environmental Management.However, August 2014 brought two violations: one for CBOD weekly average concentration, and one for CBOD monthly average. It took a few weeks, but the plant team finally identified the cause of the violations. The source of the problem was surprising — and the plant’s effluent most likely was never truly in violation.A simple changeThe trouble started on July 4, when the silicone pump tubing on the effluent sampler split during the night, and a
