Purcellville’s troubled Hirst Farm well has been shut down again. Town Manager Robert W. Lohr Jr. said this morning that two tests last week revealed the presence of E. coli bacteria.
Lohr said the Virginia Department of Health permitted the well to continue running after treatment killed the bacteria and stated there is no risk to the town’s public water system.
Out of an abundance of caution, the town closed the well. “We didn’t want that risk and exposure to citizens, so we shut it down,” Lohr said, adding that the town is exploring additional treatment options, as well as consulting with its utility advisors and the state about the best way to move forward.
The Hirst Farm well produces about 6 percent of the town’s total production.
The well has only been online since Oct. 25 after a previous E. coli finding in raw water samples in July 2015. During that period, the town, in consultation with the Department of Health, conducted extensive repairs to the well and developed an operating and monitoring system approved by VDH’s Office of Drinking Water. The town staff conducts twice-weekly sampling for the presence of fecal coliform. The town also added treatment and monitoring capabilities to guarantee disinfection to sure that drinking water was clean and safe.
During last week’s heavy rains, the E. coli problems surfaced again. Last Friday evening, a testing laboratory informed the town that one sample had tested positive for fecal coliform—the first positive result since the well re-opened.
This morning, Lohr said the town will continue to discuss options with VDH and town consultants, including coming up with a plan of action. “We’d hoped we’d addressed the issues,” Lohr said.
Last year, the town repaired a small crack in the pedestal area around the pipe, and re-grouted the well casing. Lohr said it appears water again penetrated the cracks during the heavy rains, allowing surface water enter the well. Testing will continue to see confirm the source of the infiltration, he said.
Among the options under consideration are increasing the treatment level at the Hirst Farm well or finding other sources for water production. In addition to supplying drinking water, the well provides additional pressure and water flow for the southwestern end of town.