State environmental regulators gave the owners of Oregon's only coal-fired power plant three new options Monday for shutting it down or improving pollution controls to meet federal requirements for less smog in the Columbia Gorge.

GRANTS PASS — State environmental regulators gave the owners of Oregon's only coal-fired power plant three new options Monday for shutting it down or improving pollution controls to meet federal requirements for less smog in the Columbia Gorge.

Portland General Electric Co. did not like any of the options offered by the Oregon Department of Environmental Quality for the Boardman plant, noting that each would force it to spend more money or close its cheapest source of power earlier than it has proposed.

The options reflect an extreme interpretation of federal clean air rules and would be costly to ratepayers, PGE President and CEO Jim Piro said.

"We put forward a plan for Boardman that we believe reached a good balance between cost, risk and environmental benefits," Piro said. "We'll do a complete analysis, but we're disappointed that DEQ didn't allow that plan to proceed."

Earlier this month, the Oregon Environmental Quality Commission rejected PGE's proposal to close the plant by 2020 while relying on low sulfur coal and $41 million in new pollution controls to meet emissions targets.

The commission said the plan was not likely to be approved by the U.S. Environmental Protection Agency.

At issue is meeting U.S. Clean Air Act requirements to reduce the amount of haze obscuring visibility on national park and federal wilderness lands in the Columbia Gorge, where the plant is located. The Department of Environmental Quality has labeled the plant the single worst source of haze pollution in those areas.

EPA has indicated that all three of the options would be acceptable, said Andy Ginsburg of the Air Quality Division of the Oregon DEQ.

The first option would close the plant by 2020 but cost $320 million to install new burners in 2011 that reduce nitrogen oxides emissions and scrubbers in 2014 to remove sulfur dioxide.

The second option calls for closing the plant at the end of 2018 after installing $100 million in pollution controls. The expensive scrubber would no longer be required due to the earlier closing date, but some sulfur reduction would still be necessary.

Option three calls for closing the plant by late 2015 or early 2016, with only the nitrogen oxide reductions required. The cost would be $35 million.

PGE spokesman Steve Corson said the company needs until 2020 to come up with a way to replace the power.

In the meantime, the utility is working to meet the need for new transmission lines, renewable energy production and natural gas production outside the Boardman plant.

Currently, PGE can operate the plant until 2040 but must spend more than $500 million on pollution controls.