Washington must restrict greenhouse-gas emissions from the state's five oil refineries and possibly other industries under a federal judge's ruling Friday.

The Sierra Club, the Washington Environmental Council and their lawyers at Earthjustice sued the state Ecology Department and two regional clean-air agencies in March to force them to do a better job curbing emissions from the refineries. The groups estimate the refineries are responsible for up to 8 percent of all greenhouse gases released in Washington.

Under the state's own environmental rules, U.S. District Judge Marsha Pechman noted, regulators are supposed to require "reasonably available control technology" by industrial emitters of greenhouse gases such as methane, nitrous oxide and carbon dioxide.

State regulators never actually enforced that, even though the rules were approved by the U.S. Environmental Protection Agency in 1995.

Instead, state regulators require refineries only to comply with reductions of certain other air pollutants, such as sulfur dioxide.

Earthjustice attorney Janette Brimmer called the ruling a big deal for the state.

"The court affirmed that Washington has the authority and the obligation to address impacts from climate-change pollution," she said. "Our state can no longer afford to have our regulators sit on their hands and wait for the federal government to deal with the issue. It is time for our state regulators to follow the law and implement long-overdue measures to protect our climate."

Though the environmental groups sued over the emissions from Washington's five refineries, the language of the judge's ruling — that state regulators must require reasonably available emission-control technology from emitters of greenhouse gases — would seem to apply to other industries as well.

The other major emitters of greenhouse gases in the state include the TransAlta coal-fired power plant in Centralia, which is already getting new pollution controls before it shuts down in 2025, and cement kilns.

It's not clear whether any "reasonably available technology" exists that would cut greenhouse-gas emissions from cement kilns, Brimmer said.

It is clear that oil refineries can reduce their emissions, primarily by making their processes more efficient and thus burning less fuel during refining, she said.

Seth Preston, a spokesman for the state Ecology Department, said Friday that officials had just received the ruling and were reviewing it.

"To be able to talk about far-reaching implications, we're not there yet," he said.

The refineries are BP PLC's Cherry Point near Blaine, ConocoPhillips' in Ferndale, Shell Oil's in Anacortes, Tesoro's in Anacortes and U.S. Oil's in Tacoma. A lawyer and a spokesman for the Western State Petroleum Association, which represents the refineries and intervened in the case, did not immediately return calls seeking comment.

Pechman said she would determine later how quickly the state must apply greenhouse-gas emission standards to the refineries. The environmentalists argued the state could begin enforcing the rule within 90 days, but the agencies suggested they would need three years.