HAYWARD — Opponents of a 600-megawatt natural gas-fired facility at the Hayward shoreline vowed to appeal a final permit for the project approved Wednesday.

While Calpine says that its Russell City Energy Center will be the first plant in the nation to abide by federal greenhouse gas limits, opponents say it would be anything but a victory for the environment.

"We are very disappointed that the (Bay Area Air Quality Management District) would allow the building of such a facility that is unwanted and unneeded at this time," said Audrey LePell of Hayward-based Citizens Against Pollution, a group that has fought against the plant since the project was proposed nearly a decade ago.

The power plant would use twin combined-cycle generators located on 19 acres at the corner of Depot Road and Cabot Boulevard. It would be linked to the PG&E power grid and create power for use throughout the Bay Area, with a key line traversing the Bay to the Peninsula.

LePell and other opponents say a plant like Russell City is old technology that no longer should be used.

But Calpine and natural gas proponents say it's far cleaner than coal, and cleaner than gas plants using old technology, making it an ideal "in between" facility until renewable resources become more viable forms of power generation.

They say new plants like Russell City allow for older, more-polluting models to be removed from the grid.

In approving the permit, the air board — acting under the authority of the Environmental Protection Agency — made limits on gas emissions more stringent based on public comment it received last summer that indicated new technology makes it possible.

Don Neal of Calpine said it has no problem abiding by the new regulations, which started as voluntarily caps stricter than the state mandates on pollution.

He said Calpine expects federal limits to become law, given the current administration, and added that an EPA committee looking into creating such guidelines for power plants used the Russell City permit as a model at a meeting this week.

"We're trying to get ahead of the curve," he said. "Our idea was that we wanted to undertake a process for establishing (Russell City) that would be identical to what the EPA will require."

Rob Simpson, a longtime power plant opponent, called it an "exploitation of our environment and community."

"We will continue to prove that the project is illegal and a threat to public health," said Simpson, adding that such plants "continue our dependence on and support of foreign powers. Our children will remain at risk in wars to protect dependency."

While numerous other opponents — including county Supervisor Gail Steele — have spoken against the plant at public hearings, it has a fair share of supporters.

Union workers applaud the 650 construction jobs the project will create, and others have touted the millions of dollars in city revenue that will be generated by the plant. It will use reclaimed water from the neighboring city water treatment facility, and Calpine will donate $10 million to help build a new library for Hayward.

Calpine officials said the appeal could take three to six months, but hope to break ground on the plant this year and complete it sometime in 2012.

Eric Kurhi covers Hayward. Contact him at 510-293-2473.