One of the biggest oil producers taking part in the most prolific U.S. shale play has decided to stop routine gas flaring in the Permian and plans to push for all other shale well operators to do the same. In an interview with Reuters, Exxon officials said they would insist on tougher flaring regulations in a bid to achieve a phase-out of the practice. “It levels the playing field,” the chief environmental scientist of the supermajor, Matt Kolesar, told Reuters. “We need strong regulations so it doesn’t matter who owns the…