Visibility: The issue that won't dissappear. [Air pollution control in the Grand Canyon]

This article concerns the negotiations over reducing the SO[sub 2] emissions from the Navajo Generating Station coal-fired plant 60 miles east of the Grand Canyon. After two months of negotiations, the Navajo group was able to reach an agreement with EPA and with environmental groups. The resulting agreement provided for a 90% reduction in emissions, calculated on an average annual basis. This was a greater emissions reduction than previously proposed by the EPA, and at a savings of over $1 billion. The key to the agreement was the allowance by EPA of annual averaging, which they had never allowed before. The longer period thereby allowed Navajo's owners to avoid the expense of building backup scrubber units. The agreement was negotiated under section 169A of the Clean Air Act, which is designed to protect aesthetic quality, not human health.