Period On Visibility Rule

By Nick Worth
The U.S. Environmental Protection Agency extended the public comment period for a rule proposed earlier this month that would require additional pollution controls for nitrogen oxide at three power plants in eastern Arizona. The rule would improve visibility and human health at 18 national parks and wilderness areas, includ-ing Grand Canyon, Saguaro and Petrified Forest national parks.
According to Arizona Public Service officials, the rule, as proposed, could possibly result in APS being forced to shut down Unit 2 of Cholla Power Plant near Joseph City.
APS spokesman Damon Gross said from 2007 through 2010 the company invested $324 million in upgrad-ing Cholla Power Plant’s emissions controls to meet clean air standards. He said if the proposed EPA rule takes effect, it would cost APS another $436 million. Bringing Unit 2 up to the same emission control capabili-ties as units 1, 3 and 4 would cost $126 million alone, making it cost prohibitive for APS to continue to run the unit.
Originally, the only public meeting on the proposed EPA rule was to be held on July 31 in Phoenix, with the public comment period to end on Aug. 31.
Both the Navajo County Board of Supervisors and the Holbrook City Council, along with other cities and towns in the county, recently sent letters of support to the EPA asking for an extension on the deadline for pub-lic comment, as well as public comment meetings to be held locally.
On July 26, the EPA announced it is extending the public comment period until Sept. 18, and will host two additional public hearings in Arizona. The first hearing will be held at 6 p.m. on Tuesday, Aug. 14, in the Tiponi Community Center Conference Room at Northland Pioneer College in Holbrook. The second will be held at 6 p.m. on Wednesday, Aug. 15, in rooms 113 and 115 at Cochise College in Benson.
The deadline for final EPA action remains Nov. 15.
On July 2, EPA proposed to approve Arizona’s plan that controls emissions of sulfur dioxide and coarse particles from older boilers at Apache Generating Station, Coronado Generating Station and Cholla Power Plant. In addition, EPA proposed a federal plan to limit nitrogen oxide (NOx) emissions at these plants.
Specifically, the proposal is designed to cut NOx emissions by 7,800 tons per year at Cholla Power Plant, by 4,700 tons/year at Apache Generating Station, and 4,500 tons/year at Coronado Generating Station.
Under the Clean Air Act, Congress set a long-term goal of restoring natural visibility conditions in numer-ous national parks and wilderness areas throughout the United States, known as Class 1 Areas. One of the strategies for achieving this goal is the use of best available retrofit technology at older power plants that cause or contribute to visibility impairment at Class 1 areas. The three power plants impact 18 of these areas.
For more information on the proposed rulemaking and opportunities to provide input, please go online to http://www.epa.gov/region9/air/actions/az.html#all.