A chemical designated as a human carcinogen has been found in two of Turlock’s 17 drinking water wells, but City officials say the water is still safe to drink.
The State Water Resources Control Board adopted a regulation on July 18, 2017 that went into effect Jan. 1, which creates a maximum allowable level of 1,2,3-Trichloropropane (1,2,3-TCP) — an industrial solvent that has been found as an impurity in soil fumigants and persists in groundwater. In 2013, the California Environmental Protection Agency designated TCP as a human carcinogen.
“Farmers didn’t know they were putting this on their land, they complied with all applications of their soil fumigants,” said Municipal Services Director Michael Cooke during a presentation about the new regulation to the Turlock City Council in July 2017.
Starting with the new year, the City of Turlock has had to perform quarterly monitoring, public notification if the contaminant is found, installation of wellhead treatments and implement water system chlorination.
In May, routine test results indicated that 1,2,3-TCP was present in two of the City of Turlock’s 17 drinking water wells. According to City officials, Turlock’s drinking water remains safe to drink and there is no need for customers to use an alternative water supply, such as bottled water.
The City sent out a press release stating that it is developing a corrective action plan with the anticipation of the issue being resolved by June 30, 2021. Most likely, the City will install treatment systems at the affected wells to filter the contaminant out of the drinking water.
“While it’s concerning that we’ve detected TCP in two of our 17 wells,” said Director Cooke, “I cannot reiterate enough that there is no immediate health impact to our customers and that Turlock’s water remains safe to drink. We will resolve this issue over the next three years and, in the meantime, there is no scientific data to indicate that there will be any impact to anyone’s health.”
“This situation highlights the declining quality of our groundwater and the importance of developing a drinking water supply from the Tuolumne River in partnership with the City of Ceres and the Turlock Irrigation District,” said Turlock Mayor Gary Soiseth.
In December 2017, the Turlock City Council adopted water rate increases to pay for groundwater well treatments and help fund a new surface water treatment plant. Currently, 100 percent of the City of Turlock’s drinking water supply comes from groundwater. The Cities of Turlock and Ceres, as members of the Stanislaus Regional Water Authority, have started the process of building a plant to deliver treated Tuolumne River water to homes by 2022.
