Vance water lines flushed after total coliforms detected Published Oct. 21, 2014 71st Medical Operations Squadron VANCE AIR FORCE BASE, Okla. -- On Sept. 2 Bioenvironmental Engineering received three sample results that were positive for Total Coliforms in Vance Air Force Base's water system. These tests do not cover family housing, which is a separate water system. Total Coliforms are harmless organisms that naturally exist in almost any environment and are used as a water quality indicator. "Total Coliform alone doesn't mean that the water is unsafe to drink; it's just an early indicator that water systems use to screen for possible problems," said Capt Trevor Sleight, the 71st Medical Operations Squadron bioenvironmental engineer. None of the samples contained the harmful bacteria eColi. 15,000 gallons of water were flushed out of the water mains later that week as a precaution, and all samples were repeated immediately and tested negative for Total Coliform on the repeat sample. "Further sampling in September has also been negative for Total Coliform," said Sleight. By federal law, water systems are required to notify their customers when a water quality standard is violated. "Because Vance's water system is so small, only seven samples are taken every month, and one routine sample may be positive for total coliform within that month," said Sleight. The allowable positive sample is intended to allow for sample errors and false positives, he said. Bio and Civil Engineering are currently exploring long-term options for water quality initiatives on Vance, said Sleight. For more information, call the Bioenvironmental Engineering Element at 580-213-7241, or visit Total Coliform Violation Notice ah http://www.vance.af.mil/shared/media/document/AFD-141103-011.pdf.