The Nickel Report

Since President Trump’s inauguration and the beginning of Scott Pruitt’s tenure as administrator of the U.S. Environmental Protection Agency (EPA), much of the focus of Clean Air Act activity in the new administration has been on global climate change issues. As more time passes, however, EPA is beginning to address other areas of Clean Air Act regulatory policy, and, in some respects at least, charting a new course that departs from the record of the Obama administration. One of the areas to which EPA has started to give renewed attention is the regional haze program.

During much of the Obama administration, states and EPA were in conflict about how to craft Clean Air Act plans to reduce “regional haze” impairment of visibility in national parks and wilderness areas. The technical and policy issues are daunting. Regional haze forms in the atmosphere from many sources’ air emissions — emissions from cars and trucks, construction equipment, factories and power plants (among others), plus natural sources like wildfires and dust storms. Developing regional haze implementation plans entails complex policy choices and weighing sometimes heavy compliance costs for emission controls — costs that may total in the hundreds of millions or even billions of dollars — against improvements in visibility that can be hard to measure and in some cases are even imperceptible to the human eye.