Hydraulic fracturing, or "fracking," is all about opposing forces operating under extreme pressure. Energy companies pump a mixture of water, sand and chemicals into tight shale formations in an effort to extract oil and gas. Cities respond by passing fracking bans designed to extract the energy companies. The fracking industry responds by taking the cities to court. And then Representative Jared Polis pumps some stern admonitions into the ears of the fracking industry, pressing them to stop filing lawsuits.

But at least he's polite about it.

"Please stop suing the communities I represent," begins the letter the congressman just fired off to Tisha Schuller, president of the Colorado Oil and Gas Association, after COGA filed lawsuits against Fort Collins and Lafayette challenging the approval by voters of measures prohibiting fracking in both cities. Although Lafayette's ban is the most controversial, voters in Boulder and Broomfield also approved similar ballot issues last month, imposing a five-year moratorium on new drilling permits despite COGA-backed campaigns that spent close to $900,000 to defeat the measures.

Schuller, the subject of my profile "The Insider" last June, has made no secret of her organization's determination to challenge any outright ban on fracking anywhere in Colorado; COGA is already suing Longmont over the ban it passed last year, as is the state. But Polis, who dubbed himself a fracking "poster boy" a few months ago after a drill rig showed up next door to property he owns in Weld County, isn't one to let all this litigation gush without comment.

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While Governor John Hickenlooper has insisted that the state has the primary authority to regulate oil and gas drilling, Polis believes locals have a strong case. "Elections matter," he writes. "Local governments have authority to regulate oil and gas land use activities because oil and gas operations are matters of local concern.... You can't sue, bully, or buy your way to a solution."

COGA spokesman Doug Flanders told the Daily Camera that he found the letter "encouraging," since Polis also stated that he wants the industry to thrive and find solutions. But oh, the pressure.

See the complete text of the Polis letter below.

More from our Environment archive circa August: "Video: Jared Polis, fracking 'poster boy,' bemoans drilling rig next door."