The agency's draft proposal would require the plant to cut annual emissions of sulfur dioxide and nitrogen oxides by a combined 21,000 tons. The agency said both pollutants contribute to haze, acid rain and acid deposition.
The regulator added that it estimates proposed emission controls necessary to achieve the proposed reduction levels will cost PGE $400 million when fully in place, adding that the cost could raise rates for the utility's residential and business customers by 2% to 3%.
DEQ said it plans to hold several sessions to solicit public review and comment on the draft before it begins the rule-writing process.
The agency said its draft proposal goes beyond minimum federal Clean Air Act requirements and would be one of the strongest actions taken in western states to reduce haze in national parks and scenic areas.
DEQ has scheduled an August 21 public meeting in Hermiston, Oregon, to discuss the draft and said it will convene a fiscal advisory committee in September to help evaluate the financial consequences of the proposal.
The agency said it may modify the draft proposal based on information provided by its fiscal advisory committee and the public before it makes a formal rule proposal in November. DEQ said it expects a formal public comment period on proposed rules to run from December through January, with final rules forwarded to the commission in April 2009.