California Gov. Gavin Newsom cracked down on oil producers Tuesday, halting approval of hundreds of fracking permits until independent scientists can review them and temporarily banning new wells using another drilling method that regulators believe is linked to one of the largest spills in state history. The state Division of Oil, Gas and Geothermal Resources announced it will not approve new wells that use high-pressure steam to extract oil from underground. It’s the type of process Chevron uses at an oil field in the Central Valley that leaked more than 1.3 million gallons (4.9 million liters) of oil and water this summer.