MoreThe EPA on Thursday, Jan. 7, 2010, proposed what it called the strictest health standards to date for ground-level ozone, or smog. The agency is proposing to replace the standards set by the Bush Administration.
The agency is proposing to set the "primary" standard, which focuses on human health, at a level between 0.060 and 0.070 ppm measured over eight hours. The EPA also proposed a separate "secondary" standard to protect the environment. This seasonal standard is designed to protect plants and trees from damage occurring from repeated ozone exposure, which can reduce tree growth, damage leaves, and increase susceptibility to disease, the agency said. The current eight-hour levels, set in March 2008, is 0.075 ppm for both primary and secondary standards.
In September 2009 Administrator Jackson announced that the agency would reconsider the March 2008 standards. As part of its reconsideration, the EPA conducted a review of the science that guided the 2008 decision, including more than 1,700 scientific studies and public comments from the 2008 rulemaking process. The EPA also reviewed the findings of the independent Clean Air Scientific Advisory Committee, which recommended standards in the ranges proposed today.
The EPA will take public comment for 60 days after the proposed rule is published in the Federal Register (i.e. likely sometime between Monday, March 8, and Wednesday, March 10, 2010). The agency will hold three public hearings on the proposal: Feb. 2, 2010 in Arlington, Va. and in Houston; and Feb. 4, 2010 in Sacramento.
The agency is proposing to set the "primary" standard, which focuses on human health, at a level between 0.060 and 0.070 ppm measured over eight hours. The EPA also proposed a separate "secondary" standard to protect the environment. This seasonal standard is designed to protect plants and trees from damage occurring from repeated ozone exposure, which can reduce tree growth, damage leaves, and increase susceptibility to disease, the agency said. The current eight-hour levels, set in March 2008, is 0.075 ppm for both primary and secondary standards.
In September 2009 Administrator Jackson announced that the agency would reconsider the March 2008 standards. As part of its reconsideration, the EPA conducted a review of the science that guided the 2008 decision, including more than 1,700 scientific studies and public comments from the 2008 rulemaking process. The EPA also reviewed the findings of the independent Clean Air Scientific Advisory Committee, which recommended standards in the ranges proposed today.
The EPA will take public comment for 60 days after the proposed rule is published in the Federal Register (i.e. likely sometime between Monday, March 8, and Wednesday, March 10, 2010). The agency will hold three public hearings on the proposal: Feb. 2, 2010 in Arlington, Va. and in Houston; and Feb. 4, 2010 in Sacramento.
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