Protecting California Water . . .

Pesticides used to rid California fields of insects and worms may be leaching into groundwater basins that provide almost half the state’s drinking water. But too little is known about how long they remain toxic, or even how much gets into the groundwater. A bill seeking answers to both questions is moving through the California Legislature, and deserves passage.

California and the federal government have many laws already on the books that are aimed at preserving clean water, but most deal with rivers, ponds or lakes. The vast underground water resources known as groundwater have been considered immune to pollution because contaminants presumably would degrade before reaching the water. That security has been shaken with the discovery of pesticides such as dibromochloropropane (DBCP) in California wells.

Efforts to protect groundwater have concentrated on preventing or at least discovering leaks in underground storage tanks or waste dumps. Not enough is known about the potential hazards of pesticides--about which of them remain toxic, and to what extent--largely because not enough monitoring is done to check for dangerous pesticides in the water supply. Legislation (AB 2021) sponsored by Assemblyman Lloyd G. Connelly (D-Sacramento) would increase both monitoring and testing of the toxicity of pesticide residue.

The bill, which will come before the Senate Toxics Committee on Wednesday, also would require the state Department of Food and Agriculture to set standards to indicate a pesticide’s potential for contaminating groundwater, and to restrict the use of pesticides that exceed those standards.

Connelly has been negotiating with both the department and agricultural and chemical interests, and as a result of compromises the department and the farm interests--but not the pesticide makers--are now neutral. But differences remain over whether to finance the monitoring completely out of the state budget or partly with industry fees, and over how to define pollution. It is critical that the Legislature stand firm on a strict definition of how bad is bad, or the bill has little meaning. AB 2021 is a reasonable bill that would provide much-needed protection for California’s drinking water. It should be passed.