On January 6, 2010, the U.S. Environmental Protection Agency (U.S. EPA) proposed strengthening the national ambient air quality standards (NAAQS) for ozone. The proposal results from the agency’s reconsideration of the 2008 8-hour ozone standards that was announced in September 2009. The 2008 “primary” standard, which is designed to protect public health, and the “secondary” standard, which is designed to protect sensitive vegetation and ecosystems, including forests, parks, wildlife refuges and wilderness areas are identical and set at 0.075 parts per million (ppm). Now, U.S. EPA is proposing to strengthen the 8-hour primary ozone standard to a level within the range of 0.060-0.070 ppm and is also proposing to establish a distinct cumulative, seasonal secondary standard at a level within the range of 7-15 ppm-hours. The proposed secondary standard, also called W126, is designed to account for the cumulative effects of repeated ozone exposures on sensitive vegetation during the three months of the year when ozone concentrations are highest. For a pre-publication version of the proposed rule, click here.
Stricter standards will be costly. Depending on the level of the final standard, U.S. EPA estimates the cost of implementing the standards in the proposal to range from $19 billion to $90 billion and estimates the health benefits to be between $13 billion and $100 billion. U.S. EPA conducted a supplement to the Regulatory Impact Analysis (RIA) it conducted to analyze the benefits and costs of reducing pollution to meet the ozone standards set in 2008. In the supplement to the RIA, U.S. EPA estimates the value of health benefits of reducing ozone to 0.070 ppm to range from about $13 billion to $37 billion per year in 2010 and the cost of reducing ozone to that level range from an estimated $19 billion to $25 billion per year in 2020. For a standard of 0.060 ppm, U.S. EPA estimates the value of benefits would range from $35 billion to $100 billion per year in 2010 and the cost would range from $52 billion to $90 billion per year in 2020. U.S. EPA assumed in the RIA supplement that the proposed standards could be achieved using a mixture of known air pollution control technologies and unknown, future technologies. U.S. EPA estimates that the annual control technology costs of implementing known controls as part of a strategy to obtain a standard in the proposed range of 0.060 ppm or 0.070 ppm in 2020 would be approximately $3.3 billion to $4.5 billion. While stricter standards will be costly, the Clean Air Act prohibits U.S. EPA from considering costs in setting air quality standards.
Stricter standards will also mean that more counties will not meet the stricter levels and will be identified as exceeding the new standards and designated nonattainment. Currently, 322 counties out of 675 counties with monitors violate the 2008 8-hour ozone standards of 0.075 ppm. For a map of the counties with monitors violating the 2008 8-hour ozone standards, click here. Based on 2006-2008 air quality data, U.S. EPA estimates that 515 monitored counties would violate an 8-hour standard of 0.070 ppm, an additional 95 counties would violate a standard of 0.065 ppm for a total of 608, and 42 additional counties would violate 0.060 ppm for a total of 650. For a map of counties with monitors violating primary 8-hour ground-level ozone standards in the range of 0.060-0.070 ppm, click here. Viewed from another perspective, only 25 of the counties with ozone monitors would not violate a primary standard of 0.060 ppm.
U.S. EPA also projects that, based on 2006-2008 air quality data, 196 counties with monitors would violate a secondary seasonal ground-level ozone standard of 15 ppm–hours and that 383 additional counties would violate a standard of 7 ppm–hours for a total of 579. For a map of counties with monitors violating secondary seasonal ground-level ozone standards in the range of 7-15 ppm-hours, click here.
However, if U.S. EPA finalizes ozone standards at a level below the current standards of 0.075 ppm, U.S. EPA will not designate areas as nonattainment based on 2006-2008 air quality data. U.S. EPA anticipates that designations will be based on 2008-2010 air quality data which U.S. EPA expects to show improved air quality. The improvement in air quality is due in part to reductions made by power plants under the Clean Air Interstate Rule that currently remains in effect although the D.C. Circuit found fundamental flaws in it and remanded it to U.S. EPA. While the number of counties designated nonattainment may be less than depicted on U.S. EPA’s maps, the number will still be substantial and will mean additional air quality planning obligations for states and controls for sources in nonattainment areas.
U.S. EPA is proposing an accelerated schedule for designating areas as attainment, nonattainment, or unclassifiable for the primary ozone standard. The proposed accelerated schedule is as follows: (1) state Governors submit their recommendations by January 2011; (2) U.S. EPA promulgates final designations by July 2011; (3) designations take effect August 2011; and (3) states with nonattainment areas submit their state implementation plans describing how they will reduce pollution to meet the standards by December 2013. Depending upon the severity of the air quality problem, states would be required to meet the primary standard by 2014–2031. U.S. EPA is planning to propose an implementation rule in the spring of 2010 and issue a final rule as quickly as possible after the final ozone NAAQS that U.S. EPA plans to sign by August 31, 2010. U.S. EPA is taking comment on whether to designate areas for a seasonal secondary standard on an accelerated schedule or a two-year schedule.
U.S. EPA is not proposing to modify the ozone monitoring requirements for ozone. U.S. EPA proposed in July 2009 modifications to the ozone air quality monitoring network design requirements. The proposed monitoring revisions would modify minimum monitoring requirements in urban areas, add new minimum monitoring requirements in non-urban areas, and extend the length of the required ozone monitoring season in many states. U.S. EPA estimates that about 270 new ozone monitors would be required under the proposed monitoring requirements. U.S. EPA expects to issue a final ozone air quality monitoring rule in late summer of 2010.
Meanwhile, the 2008 8-hour ozone NAAQS and the 1997 8-hour ozone NAAQS (0.08 ppm) remain in place. Implementation for the 2008 8-hour ozone NAAQS is delayed, however. U.S. EPA announced on January 6, 2010, it is extending the deadline for area designations for the 2008 ozone standards by one year or until March 12, 2011. If U.S. EPA issues stricter ozone standards in 2010, these standards would replace the 2008 ozone standards and implementation requirements for the 2008 ozone standards, including designations would no longer apply. Meanwhile, states are to continue their plans for implementing the 1997 NAAQS.
The 2008 standards were adopted under the Bush Administration and were not consistent with recommendations by U.S. EPA’s science advisory panel, the Clean Air Scientific Advisory Committee (CASAC). The range for the proposed standards is consistent with CASAC’s recommendations. If U.S. EPA finalizes standards within that range, they will be more difficult for environmental groups to challenge as insufficiently protective. The D.C. Circuit recently remanded the annual PM2.5 NAAQS which were also inconsistent with CASAC’s recommendations.
While the proposed standards are consistent with CASAC’s recommendations, U.S. EPA based its reconsideration on studies about the health and ecological effects of ozone that were in the record for the 2008 ozone standards. U.S. EPA did not rely on studies that had been published since the science assessment for the 2008 review. Instead, U.S. EPA conducted a “provisional” assessment of studies since the 2008 review was completed and maintains that the new studies do not materially change the conclusions of its earlier science assessment. Whether U.S. EPA used the best science in declining to undertake a full assessment of newer science since the last review may be an issue in any challenges to the ozone standards if they are finalized at a level below 0.075 ppm.
By 2020, U.S. EPA projects that 99 counties with monitors would violate a standard of 0.070 ppm, 149 additional counties would violate a primary standard of 0.065 ppm for a total of 248, and 203 additional counties would violate a standard of 0.060 ppm for a total of 451. For a map of counties with monitors projected to violate a primary 8-hour ozone standard in the range of 0.060 0.070 ppm in 2020, click here. U.S. EPA also projects that by 2020 27 counties would violate a secondary seasonal standard of 15 ppm–hours and 167 additional counties would violate a standard of 7 ppm-hours for a total of 194. For a map of counties with monitors projected to violate the secondary seasonal ozone standards in the range of 7-15 ppm-hours by 2020, click here.
These projections for 2020 are based on modeled emissions that reflect expected emissions reductions from federal programs some of which are expected to be made stringent than the programs used in the modeling. For example, although the Clean Air Interstate Rule remains in effect while U.S. EPA considers a replacement rule, the replacement rule is expected to be more stringent when finalized in 2011 than the current rule. In addition, the Clean Air Mercury Rule was vacated by the D.C. Circuit and U.S. EPA is obligated under a consent decree to promulgate maximum achievable control technology standard for mercury and other hazardous air pollutants from power plants by November 2011.
Following publication of the proposed rule and the Federal Register, U.S. EPA will take public comment for 60 days. U.S. EPA will also hold public hearings in Arlington, Virginia and Houston, Texas on February 2, 2010, and in Sacramento, California on February 4, 2010.
This article was authored by Gale Lea Rubrecht, Jackson Kelly PLLC. For more information on the author, see here.