DENVER - Colorado gas and oil companies could soon face the strictest air quality rules in the U.S.

The state air quality board expects to meet four or five days starting Wednesday to adopt new rules, which have divided both the industry and the environmental community.

"These rules are incredibly important," said Dan Grossman, regional director for the Environmental Defense Fund, and a prime supporter of the plan.

The rules would require companies to detect leaks from their equipment and repair them quickly, and to stop venting methane into the atmosphere. It would be the first time any state in the country mandates the capture of methane.

Gov. John Hickenlooper announced his support for the proposal in November. He's backed by three oil and gas companies - Noble Energy, Anadarko and Encana - as well as the Environmental Defense Fund. But with most other energy companies opposed, and other environmental groups wanting a tougher rule, there's no guarantee the Air Quality Control Commission will give Hickenlooper what he wants.