UPDATE: Environmental Protection Agency Proposes Stricter Standards For Smog

On January 7, 2010, the Environmental Protection Agency (“EPA”) announced its strictest smog health standards to date, noting that smog is linked to numerous health problems. The EPA stated that it “is proposing to replace the standards set by the previous administration, which many believe were not protective enough of human health.” The new standards will result in a large increase in the number of counties violating ozone standards.

Ground level ozone, which is the main component of smog, is not emitted directly into the air but forms when emissions from industrial facilities, power plants, exhaust from motor vehicles, and other sources react in the sun. Exposure to ozone is linked to serious health problems, particularly in children because their lungs are still forming, and in adults who have lung disease. According to the EPA, breathing air that contains ozone can reduce lung functions and inflame airways. Exposure to ozone has been associated with increased respiratory illnesses, increased use of medication, and increased emergency room visits and hospital admissions.

The EPA proposal will set the primary standard, which protects public health, at a level between .060 and .070 parts per million (“ppm”) measured over a period of eight hours. The EPA also proposes establishing a seasonal secondary standard, which is designed to protect sensitive trees and plants in forests, parks, wildlife refuges and wilderness areas from repeated ozone exposure. The proposed level of the secondary standard is to be set at a range between 7-15 ppm-hours. The previous primary and secondary standard was set at .075 ppm in 2008.

Compliance for the primary standard will be determined by examining ozone concentration averages over eight hour periods. The fourth highest eight-hour value at a particular monitor will be averaged with the fourth-highest eight-hour values from the previous years to produce a three-year average. To meet the standard established by the EPA, that three-year average must be less than or equal to the level of the standard.

Compliance with the proposed secondary standard will be determined during the three months when daytime ozone concentrations are at their highest. The new method of calculation is a “cumulative peak-weighted index” called W126. W126 is to be calculated by “‘weighting’ each hourly ozone measurement during the 12 daylight hours (8:00 am to 8:00 pm) each day, with more weight given to higher concentrations.” These 12 measurements are then added together to get a cumulative daily value. The daily values are then added together to get a cumulative monthly value. The three consecutive months with the highest index values are identified to get the cumulative seasonal value index. The seasonal index values will then be averaged over three years. An area will “meet the proposed secondary standard if the three-year average of the cumulative seasonal index values is less than or equal to the level of the standard (i.e., 7-15 ppm-hours).”

The EPA has set out an estimated timeline for implementing the proposed standards. States must make recommendations for areas to be designated attainment, nonattainment, or unclassifiable by January 2011. The EPA will make final area designations by July 2011 and the designations will become effective in August 2011. States must submit state implementation plans to the EPA in December 2013. The deadlines for meeting the primary standards will be set between 2014 through 2031, with the exact deadline to be determined depending on the severity of the problem.

The EPA will take public comments for 60 days after the proposal is published in the Federal Register. The EPA will then issue final standards by August 31, 2010.


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