Many new, unfamiliar names on latest list of America’s top methane emitters

As the world’s oil and gas giants face increasing pressure to reduce their fossil fuel emissions, small, privately held drilling companies are becoming the country’s biggest emitters of greenhouse gases, often by buying up the industry’s high-polluting assets.

According to a startling new analysis of the latest emissions data disclosed to the Environmental Protection Agency, five of the industry’s top 10 emitters of methane, a particularly potent planet-warming gas, are little-known oil and gas producers, some backed by obscure investment firms, whose environmental footprints are wildly large relative to their production.

In some cases, the companies are buying assets directly from the largest oil and gas corporations, like Conoco Phillips and BP; in other cases, private equity firms acquire risky oil and gas properties, develop them and sell them quickly for maximum profits.

The largest emitter, Hilcorp Energy, reported almost 50 percent more methane emissions from its operations than the nation’s largest fossil fuel producer, Exxon Mobil, despite pumping far less oil and gas. Four other relatively unknown companies — Terra Energy Partners, Flywheel Energy, Blackbeard Operating and Scout Energy — each reported emitting more of the gas than many industry heavyweights.

These companies have largely escaped public scrutiny, even as they have become major polluters.