The Environmental Protection Agency announced this week that it is proposing pollution controls at three Arizona power plants in order to improve air quality at 18 national parks and wilderness areas. Here are the details.
* According to EPA, its proposal to approve Arizona's air quality plan to control sulfur dioxide and soot at three power plants will improve visibility and human health at places such as the Grand Canyon, Saguaro National Park and the Petrified Forest. Ninety percent of the time, the Grand Canyon's air is impaired by pollution, which also reduces the Grand Canyon's views by more than 30 percent.
* Arizona's plan calls for emissions controls of sulfur dioxide and coarse particles from the eastern Arizona Cholla, Apache and Coronado plants. The EPA is additionally proposing to limit nitrogen oxides at these plants.
* The Arizona Republic reported that the owners of these power plants have already planned upgrades and that the expenses incurred by the EPA's proposal will be paid by the customers.
* The proposal calls for equipment that costs up to $110 million to be added to a generator at the Coronado plant, as well as two at Apache and three at Cholla.
* Salt River Project, which owns the Coronado Generating Station, has already spent $500 million trying to reduce emissions. Arizona Public Service, which owns the Cholla plant, has spent about $350 million already and has reduced emissions by 65 percent, The Republic reported.
* The EPA stated that its proposal is consistent with the Clean Air Act's long-term goal of restoring natural visibility conditions at natural parks and wilderness areas. One strategy for achieving this, the administration explained, is the use of Best Available Retrofit Technology at older power plants.
* Environmental organizations such as the Environmental Defense Fund praised the proposal, stating that in addition to increasing visibility at the parks -the "plan provides critical health protections for Arizona's citizens."
* According to the Environmental Defense Fund, the proposal is "an opportunity to transition older power plants, such as Cholla, to cleaner sources of energy."
* The EPA is soliciting public comments through Aug. 31 on its proposed approval of the state's plan, and is hosting a public workshop and hearing on July 31 in Phoenix. Final EPA action is expected to occur by a Nov. 15 deadline, the EPA stated.
* A number of environmental organizations joined a suit filed in 2008 against the EPA for missing deadlines for limiting haze in Arizona, The Republic reported.