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A Park with a View: EPA Sets Schedule to Improve Visibility at National Parks

Last week the United States Environmental Protection Agency (EPA), in an effort to resolve ongoing litigation under the Clean Air Act with environmental groups over dozens of past due state implementation plans (SIP), agreed to a schedule for taking action on more than 40 state plans aimed at lowering haze in national parks and wilderness areas.

Regional haze, the visibility impairment produced by a multitude of sources and activities that emit fine particles and their precursors across a broad geographic area, has decreased the average visual range in western national parks from 140 miles to 35 to 90 miles, and in eastern parks, from 90 miles to 15 to 25 miles. To address this problem, EPA promulgated regulations in 1999 requiring states to develop and submit SIPs to improve visibility in 156 national parks and wilderness areas, including the Grand Canyon, Yosemite, and Shenandoah Valley. These plans, which focus on reducing harmful pollution from large, older stationary sources, such as power plants, cement plants and large industrial boilers, were due in December 2007. In January 2009, EPA found that the majority of states had failed to submit their regional haze plans, in full or in part, and in August 2011, the National Parks Conservation Association and Sierra Club, among others, initiated litigation in federal Court to end the on-going delay.

Under the terms of the proposed consent decree, EPA must issue final plans for 34 states and territories by deadlines that range from December 13, 2011 to November 15, 2012, and must approve or disapprove the proposed plans of nine other states and one region no later than June 15, 2012. In cases where EPA does not approve a state proposal, the agency must determine an appropriate federal plan. EPA is accepting public comments on its proposed agreement for 30 days following publication of a notice in the Federal Register.

Haze results when sunlight encounters tiny, suspended particles in the air, which absorb and scatter light, reducing the clarity, color, texture, and form of objects in view. The pollutants that reduce visibility include fine particulate matter and compounds that contribute to its formation, such as nitrogen oxides and sulfur dioxides.

Per EPA, yearly visitors to our nation’s parks and wilderness areas often discover that they are not able to see the nation’s spectacular vistas because a blurring veil of white or brown haze hangs in the air much of the year. Most of this haze is the result of air pollution carried by the wind from origination points many hundreds of miles away.

Categories: Air Quality