California may put oil companies on the financial hook to plug and clean aging oil fields after lawmakers approved a measure meant to prevent taxpayers from footing the bill for orphaned wells. In a year that has been relatively quiet for climate legislation, the passage of Assembly Bill 1167 on Thursday night marked a win for environmentalists and communities mainly around Los Angeles and the San Joaquin Valley facing methane leaks from aging oil wells that require costly cleanup. … Orphaned wells, as they’re called, risk harmful leaks of oil, polluted water and methane often near residential areas. According to the Geologic Energy Management Division, known as CalGEM, California has plugged about 1,400 wells since 1977 at a cost of $29.5 million.