The Environmental Protection Agency is expected to adopt rules to reduce air pollution from gas development in places such as the Upper Green River Valley, several groups said Monday.

If enacted, the EPA rules should reduce air pollution from emissions caused by hydraulic fracturing and other energy industry practices in places that have experienced a boom in natural gas development, groups said. Representatives from Sierra Club, Earthjustice, the Clean Air Task Force, the Natural Resources Defense Council and the Environmental Defense Fund made the comments in a teleconference Monday.

The rules “will help rein in a dirty industry that has gone unchecked for way too long,” said Deb Nardone, with Sierra Club. “Natural gas frackers will no longer be able to recklessly dump pollution into our air. The upcoming announcement from EPA is really going to be a first step in helping families.”

In recent years, pollution from energy development has prompted Wyoming Department of Environ-mental Quality officials to warn of high, unhealthy ozone levels for the Upper Green River Valley. Smog levels in rural communities south of Jackson have rivaled big cities such as Los Angeles.

“A drilling boom has also brought serious ozone pollution problems to rural areas, such as western Wyoming and eastern Utah,” a coalition of 31 conservation groups said in comments to the EPA about the proposed rules. “In Wyoming’s Upper Green River Basin, for 13 days last winter alone residents suffered ‘unhealthy’ ozone concentrations under EPA’s current standards, including days when the ozone pollution levels exceeded the worst days of smog pollution in Los Angeles.”

Earthjustice represented Wild Earth Guardians and San Juan Citizens Alliance in a lawsuit to force the EPA to develop the rules, which were originally set for release today.

The EPA requested and received an extension for the rules until April 17.

The EPA’s existing air quality standards for gas development are inadequate and out of date, said Robin Cooley, an attorney for Earthjustice.

“Some of these standards we’re talking about have been around for 27 years,” she said. “The rule is long overdue. For too long, the people who live in and around natural gas fields have been forced to breathe dangerous pollution.”

The pollutants released from gas development include benzene, a known carcinogen, and volatile organic chemicals, which are known to be the precursors of ozone.

The new EPA rules are expected to require companies to capture gases released into the air during the fracturing process. One of those is methane, a greenhouse gas.

Methane emissions from energy development account for roughly 37 percent of the methane emissions in the United States, according to the Natural Resources Defense Council. While some states already have standards in place for capturing these emissions, many do not.

In a relatively short time, the money made by capturing and selling these emissions can repay developers for the equipment used to capture the emissions, said David Doniger, a climate and clean air advocate for the Natural Resources Defense Council.

Technology to capture the gas is “readily available and highly profitable,” Doniger said.

The EPA titles the regulation “New Source Performance Standards and National Emission Standards for Hazardous Air Pollutants.”