California’s Legislature last week passed the toughest fracking law in the nation. Environmentalists should be heralding the work of SB 4’s author, Sen. Fran Pavley, D-Agoura Hills, whose green credentials are well established.

They are instead calling on Gov. Jerry Brown to veto the legislation, which, thankfully, he won’t. Brown said last week that he’ll gladly sign the bill, for all the right reasons: The legislation requires that oil companies disclose the chemicals they use in the process, formally known as hydraulic fracturing, which involves pumping water and other substances into shale formations to extract natural gas and has prompted concerns about groundwater contamination. It also requires that drillers notify property owners 30 days in advance of doing any fracking and demands that they test groundwater before and after any operation in order to monitor water quality.

The bill also calls for a statewide environmental impact review of the process that will be completed by 2015. If the study indicates tougher restrictions are needed, the Legislature can act.

Some environmentalists won’t be happy unless there is a complete ban on fracking or a moratorium until the environmental impact review is complete. But studies by the Environmental Protection Agency have not linked fracking by oil companies to groundwater contamination.

SB 4 was a reaction to new drilling techniques allowing the extraction of oil and natural gas from the Monterey Shale, which stretches from Modesto to Bakersfield and is believed to hold more than 15 billion barrels of oil — enough to fuel the nation for three years. The potential benefits are enormous, including thousands of jobs and desperately needed tax revenue.

California currently has no regulations governing fracking, and it needs them given its seismic history and fragile water supply.

Pavley’s legislation gives the state the toughest laws in the United States, and it paves the way for even stricter laws if scientific reviews indicate they are necessary.