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 new analysis of the latest emissions data disclosed to the Environmental Protection Agency, five of the industry’s top ten 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 up high-polluting assets directly from the largest oil and gas corporations, like ConocoPhillips 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 […]