|Counties projected to violate proposed Primary 8-hour Ground-Level Ozone Standards in 2020. Source: EPA. Click to enlarge.
The United States Environmental Protection Agency has proposed the strictest standards to date for ground-level ozone. Ground-level ozone forms when emissions from industrial facilities, power plants, landfills and motor vehicles react in the sun.
The agency is proposing to set the “primary” standard, which protects public health, at a level between 0.060 and 0.070 parts per million (ppm) measured over eight hours. EPA is also proposing to set a separate “secondary” standard to protect the environment within the range of 7-15 ppm-hours. 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.
In September 2009 Administrator Jackson announced that EPA would reconsider the existing ozone standards, set at 0.075 ppm in March 2008. As part of its reconsideration, 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. EPA also reviewed the findings of the independent Clean Air Scientific Advisory Committee, which recommended standards in the ranges of the new proposal.
EPA is proposing an accelerated schedule for designating areas for the primary ozone standard. Also, EPA is taking comment on whether to designate areas for a seasonal secondary standard on an accelerated schedule or a 2-year schedule. The accelerated schedule would be:
By January 2011: States make recommendations for areas to be designated attainment, nonattainment or unclassifiable.
By July 2011: EPA makes final area designations.
August 2011 Designations become effective.
December 2013: State Implementation Plans, outlining how states will reduce pollution to meet the standards, are due to EPA.
2014 to 2031: States are required to meet the primary standard, with deadlines depending on the severity of the problem.
Ground-level ozone (smog) is linked to a number of serious health problems, ranging from aggravation of asthma to increased risk of premature death in people with heart or lung disease. Ozone can also harm otherwise healthy people who work and play outdoors.
Depending on the level of the final standard, the proposal would yield health benefits between $13 billion and $100 billion, according to the EPA. This proposal would help reduce premature deaths, aggravated asthma, bronchitis cases, hospital and emergency room visits and days when people miss work or school because of ozone-related symptoms. Estimated costs of implementing this proposal range from $19 billion to $90 billion.
EPA will take public comment for 60 days after the proposed rule is published in the Federal Register. The agency will hold three public hearings on the proposal: 2 Feb. 2010 in Arlington, Va. and in Houston; and 4 Feb. 2010 in Sacramento.