Closure of plant will help clear Gorge air
Experts to deliver results of decade of study Tuesday
Monday, September 12, 2011
The haze that blurs scenic views in the Columbia River Gorge for many days each year isn’t decreasing. But it isn’t getting worse either, even with population growth in the Portland-Vancouver metro area, and the closure of Oregon’s only coal-fired plant in 2020 will help restore the sweeping vistas that gave the nation’s only national scenic area its name.
That’s part of the message Washington and Oregon air quality experts will deliver to the Columbia River Gorge Commission on Tuesday after more than a decade of research and monitoring of Gorge air quality.
Portland General Electric’s coal-fired plant in Boardman, Ore., located east of the national scenic area boundary, remains the most significant individual contributor to haze, air quality issues and acid precipitation in the Gorge, air quality experts said. The Boardman plant is now scheduled to close in 2020; between now and then, it’s expected to reduce haze-producing emissions by nearly half.
The Gorge Commission’s involvement in air quality issues dates to 2000, when the bistate panel amended its management plan to state that air quality in the scenic area “shall be protected and enhanced” consistent with the purposes of the 1986 National Scenic Area Act.
The commission, which has had neither a staff nor a budget to work directly on air quality issues, asked the states to develop and implement a regional air quality strategy that would lead to improvements in haze. The U.S. Forest Service contributed to the effort by expanding its own air monitoring program in both the western and eastern Gorge.
In 2003, when the Washington Department of Ecology stopped funding its haze management program, the Vancouver-based Southwest Clean Air Agency stepped in to fill the gap. Both states continue to monitor haze-producing emissions in the Gorge, but plans for a bistate air quality advisory committee and more technical studies were scrapped or scaled back after 2003 due to lack of funding.
The Yakama Nation and the Confederated Tribes of the Umatilla Indian Reservation, concerned about the deterioration of Indian rock art due to acid precipitation, commissioned their own air quality studies.
Air quality experts determined that sources from throughout the region, even from as far away as Canada, contribute to haze in the Gorge. The impaired visibility is noticeable in both winter and summer but is generally worse in winter, they said. Portland-area emissions contribute to summertime haze in the western Gorge, but the so-called “Portland plume” is not a primary contributor to winter haze, they concluded.
The air quality agencies decided not to set a numerical goal for improving air quality in the Gorge. There’s no scientific justification for defending such a standard, they said, and “widely divergent and strongly held opinions” among Gorge residents about what an appropriate goal would be likely “would lead to a long and divisive debate” that could actually become an obstacle to achieving air quality improvements.
The most efficient way to stay on top of air quality trends going forward, they said, is through implementation of the federally mandated Regional Haze Program. Part of the federal Clean Air Act, the program sets standards intended to lead to pristine air quality with “no man-made impairment” in national parks and wilderness areas, known as Class 1 areas, by the year 2064. It requires five-year progress reports and stringent emission controls on major sources of haze, such as the Boardman plant.
The Gorge itself is not a Class 1 area and never will be, the experts said.
“Due to the mix of urban and rural activities in the Gorge, long-term visibility improvements cannot be expected to reach ‘natural conditions’ as is the case for pristine wilderness areas and natural parks,” they said. But the Gorge, sandwiched between wilderness areas around Mount Adams to the north and Mount Hood to the south, will benefit significantly from measures taken to improve visibility in those Class 1 airsheds, they said.
Adopting the Regional Haze Program as the strategy to improve visibility in the Gorge “provides milestones, benchmarks and the legal framework that would not otherwise exist” for taking action to reduce haze in the Gorge, the experts said.
Stringent new emission controls at the 600-megawatt Boardman plant are expected to reduce haze-forming emissions by 48 percent between now and 2019 and eliminate those emissions when the plant closes at the end of 2020. Sulfur dioxide and nitrogen oxide emissions from the plant can travel as far as 200 miles and currently contribute to impaired visibility in 14 Class 1 areas in Oregon, Washington and Idaho.
Phased closure of the Trans-Alta coal-fired plant near Centralia beginning in 2025 also is expected to reduce regional haze. That plant is twice the size of the Boardman plant.
Other sources that mar air quality in the Gorge include natural wildfires, emissions from autos, ships, locomotives and construction equipment, and residential heating. Regulatory efforts requiring vehicles to meet low emission standards, retrofitting of diesel engines to use ultra-low sulfur fuels, and development of smoke management plans to keep smoke out of the Gorge during prescribed burns all will contribute to improved visibility over time, said Paul Mairose, chief engineer for Southwest Clean Air.
“We anticipate the early years may be easier to get progress than in the latter years,” Mairose said. “In the early years, we’re taking a look at major point sources. We know that transportation and other sources are bigger contributors. There will be a lot of opportunities in the future to replace our carbon-based fuel engines.”