If three environmental groups have their way, California’s mammoth agriculture industry will be subject to state water-pollution laws for the first time in history. The three groups (San Francisco BayKeeper, DeltaKeeper, and the California Public Interest Research Group) filed suit yesterday against the Central Valley Regional Water Control Board to close a loophole that allows farmers in the Central Valley to discharge pesticide-filled irrigation runoff without a permit. The federal Clean Water Act exempts agricultural runoff, and in California, farmers are not subject to the restrictions imposed on other industries. The result, according to the allegations in the lawsuit, is that every year, millions of gallons of polluted agricultural runoff flow into the San Joaquin and Sacramento rivers, and from there into the San Francisco Bay, where it kills and injures marine life.