Cesar Aguirre first became aware of a potential methane leak in Bakersfield about a month ago. He says that he heard the news from a resident who reported hearing a “hissing” sound coming from an oil well near their home. And sure enough, after investigation, the California Geologic Energy Management Division, or CalGEM, confirmed the report. They found dozens of oil wells in need of remediation, with 21 leaking explosive levels of methane gas in various neighborhoods in Bakersfield. … When improperly abandoned, idle wells can contaminate air and drinking water.