The California State Water Resources Control Board will soon set a maximum contaminant level for 1,2,3 Trichloropropane, or 1,2,3 TCP.
It's currently found in industrial solvents and cleaning agents, but it was once found in two popular soil fumigants made by Dow Chemical and Shell Oil Company.
The pesticide byproduct contaminated groundwater throughout the Central Valley. State water regulators have found 1,2,3 TCP in 94 public drinking water systems in 16 counties.
Right now, water systems in California are only required to notify residents if the chemical is found at a certain health-based advisory level.
“But they are not required to do anything about it. They’re not required to treat it," says Asha Kreiling with the environmental justice group Community Water Action. "It’s totally legal to be in the water, although we know this is a human carcinogen. Having a MCL [Maximum Contaminant Level] established will require public water systems to treat the water.”
The State Water Resources Control Board will hold public meetings in Sacramento, Fresno, and Bakersfield this month to discuss what the legal limit should be.
Environmental groups want regulators to set the lowest and most protective level possible so that the companies responsible for the contamination are paying for treatment.
Regulators are expected to make an official recommendation in the fall.