The state Assembly has passed the country's strongest legislation… (Patrick T. Fallon / Bloomberg )
SACRAMENTO -- A bill that would give California the nation's toughest regulation of a controversial oil drilling technique won easy passage Wednesday from the state Assembly.
SB 4 by Sen. Fran Pavley (D-Agoura Hills) cleared the Assembly on a 47-17 vote and went back to the Senate for concurrence in amendments. The Senate previously passed it by a 28-11 vote.
The measure had widespread support from most environmental groups, but they pulled their support just before the Assembly vote Wednesday. They argued that the proposal was too weak and did not force drillers to disclose all needed information about chemicals injected in wells.
Oil companies opposed the bill, arguing it would make it harder for them to exploit the estimated 15 billion barrels of oil in the Monterey Shale Formation in the southern San Joaquin Valley.
Pavley said her bill is needed because California currently does not regulate the practice of hydraulic fracturing, a process that involves injecting mixtures of sand, water and chemicals to free oil and natural gas trapped deep underground in shale formations.
State regulators also do not oversee a related "well stimulation" process that uses acid to retrieve the hydrocarbons, she said.
Pavley's bill, if it becomes law, would require drillers to obtain permits for fracking and acidizing. It also would mandate notification of neighbors, public disclosure of all chemicals used and ground and water quality monitoring.
Gov. Jerry Brown has not commented publicly on whether he would sign the bill. But Pavley indicated the governor told her Tuesday that he would sign the bill.
The governor also has given assurances to the oil companies that some of their concerns would be addressed by proposed state regulations due to be completed this year, Pavley said.
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