NORTH SALT LAKE -- Two South Davis mayors are keeping watch on their shrinking drinking water supply as they contend with PCE-contaminated wells and growing populations.
Woods Cross has had four wells and North Salt Lake has had two wells closed because of a tetrachloroethylene underground plume, which for more than 40 years has continued to leach from its original place of origin -- a former dry-cleaning business at "Five Points" in Woods Cross.
"The groundwater contains PCE at a level above what we have deemed acceptable," said Hans Millican, with the Division of Environmental Response and Remediation.
Because the wells do not meet quality standards, they have been closed down, officials said.
Two of North Salt Lake's wells, which are in Woods Cross, were found contaminated with PCE in 2009 and have since been shut down, said North Salt Lake Mayor Len Arave.
"We closed our wells down," Arave said. "It is not something we take lightly, and we have arranged for some other water sources."
Since losing two of its wells, Arave said, the city in the last 18 months has drilled an additional well, which will serve as a reserve to provide a total of three PCE-free wells to serve the city.
The city has also decided to buy some additional shares of secondary water from Weber Basin Water Conservancy District to take some stress off its culinary water supply being used to care for lawns and lots, he said.
Woods Cross leaders are taking similar measures as they debate whether to bond for $4 million to build and operate a centralized "granular activated carbon system" to remove the PCE from the groundwater, said Woods Cross Mayor Kent Parry.
"It's like having a water filter on your tap, only a larger facility," with the PCE being absorbed by the carbon, he said.
The project would cost each rate payer about $10 more a month on each water bill, Parry said.
The other option available would be to continue to have residents consume the water with traces of PCE in it, at levels that would put it at "one-in-a-million" of being a cancer-causing agent, he said.
The Environmental Protection Agency has set a maximum contaminant level for PCE at 5 parts per billion. Some people who drink water containing PCE in excess of the maximum contaminant level over many years could have problems with their liver and may have an increased risk of getting cancer, according to the EPA website.
"The most the wells have shown (in Woods Cross) is about one-tenth of that," Parry said.
"That is the debate the council and I have to decide. Right now, we have one well that is PCE-free."
But the underground plume is moving toward the city's lone well that remains PCE-free, he said.
City officials have been aware of the problem for several months and held an open house with residents to get their input regarding which alternative they want the city to take, Parry said.
But for whatever reason, the city has received only 27 responses from its 9,500 residents, he said, and he and the council are not comfortable in making a $4 million decision based on 27 responses.
The council is considering making the decision part of a Nov. 5 voter referendum, Parry said. By doing so, he said, the council would get at least 1,300 residents to respond on the matter.
"We would like nothing more than to have tons of public input on this."