Clean Air: EPA Toughens Standards For SO_2 Emissions

摘要

The U.S. Environmental Protection Agency has set more stringent new air-quality standards for sulfur dioxide (SO_2). In a final regulation announced on June 3, EPA is jettisoning the current standard, which is 140 parts per billion over 24 hours, in favor of a one-hour, 75-ppb level.rnThe estimated cost to fully implement the new standard by 2020 is $1.5 billion, EPA says.