Four of 10 electric membership cooperatives planning a $2 billion coal-fired power plant in Washington County have pulled out of the project, according to environmental groups that have campaigned against the 850-megawatt generating station.

Jackson Electric Membership Corp., Diverse Power Inc., Excelsior EMC and GreyStone Power Corp. announced this week their intention to abandon participation in the project, said Midge Sweet, the campaign director for Georgians for Smart Energy.

The plant, which would be built near Sandersville, about 70 miles from Augusta, would use coal to generate electricity for as many as 700,000 people.

The consortium planning the project, Power4Georgians LLC, still has six partners who would undertake a larger stake in the new plant.

Georgians for Smart Energy contends the plant would emit unacceptable levels of pollution and have lobbied for investments in cleaner power sources.

Georgia's Environmental Protection Division, which is processing permits for the plant, estimates the plant's annual emissions would include 678 tons of soot particles, 1,896 tons of sulfur dioxide, 145 tons of sulfuric acid, 1,160 pounds of lead, 120 pounds of mercury.

Ms. Sweet said in a news release Wednesday that Georgians for Smart Energy will continue efforts to persuade the project's remaining partners, including two in the Atlanta area -- Snapping Shoals EMC and Cobb EMC -- to pull out of the consortium.