September 26, 2014
The Unknown in Ozone: Impacts from future National Ambient Air Quality Standard (NAAQS) for Ozone (O3)
When EPA proposes/promulgates a new NAAQS, states must evaluate ambient air monitoring data and submit recommendations to identify areas that will be non-attainment with the new NAAQS. Next, states must develop/revise State Implementation Plans (SIPs) that identify sources within their jurisdiction that are significant emission contributors to the pollutant of concern promulgated in NAAQS. States must propose emission reduction measures (new/updated state & local air regulations) and their projected impact to show justification for how proposed measures will achieve attainment with NAAQS by a specified date.
As a result of this process, new state/local regulations become effective which place tighter emission standards on stationary sources in attainment and non-attainment areas with NAAQS. By rule, SIP submittals cannot exclude any source category (e.g. minor sources) from participating in necessary emission reductions for attainment with a NAAQS. Stationary sources in non-attainment areas for a NAAQS will have more rigorous air permit requirements within the NSR program. Existing source major modifications will receive Non-Attainment Area (NAA) permits which can require Lowest Achievable Emission Rate (LAER) pollutant standards. LAER is the most stringent level of control required under the Clean Air Act; LAER does not consider economic cost for emission reductions and can require large capital costs for modest emission reductions.
If proposed Ozone NAAQS are set at 60 ppb (as has been suggested), EPA estimates 451 counties in 44 states are projected to be in nonattainment. Criteria Pollutants CO, NOx and VOC are precursors to atmospheric O3 formation; meaning significant emission reductions from stationary sources for each pollutant will be required for areas to reach attainment. Moreover, state agencies have limited regulatory authority to reduce ozone and precursor emissions from the 2nd largest emission group, mobile sources (28% of GHG emissions nationally), because mobile source emission standards are administered by EPA and not state agencies. For Kentucky, EPA has only identified 22% of emission reductions needed to meet the standard. The remaining 78% of emission reductions have to come from measures yet to be determined to achieve attainment with 60 ppb O3 NAAQS.
Future Proposed Ozone NAAQS of 60-70 ppb:
- Current O3 NAAQS set in 2008 at 75 ppb
- Proposed O3 NAAQS due late 2014 and is projected to be between 60-70 ppb.
- EPA is prohibited from evaluating cost effectiveness for public health quality in Setting NAAQS, but is required by congress to produce a Regulatory Impact Analysis (RIA) for projected economic impact.
- EPA’s RIA stated that the costs of new O3 NAAQS could exceed $100 billion annually once promulgated.
- The National Association of Manufacturers projects much greater economic impact ranging from $270-360 billion of GDP reduction annually after promulgation.
- Projected O3 NAAQS Promulgation date is late 2015, non-attainment areas have 3-20 years to reach attainment
- As of November 2009, 122 million people (about 40% of the U.S. population) lived in areas classified “nonattainment” for the primary 1997 ozone NAAQS.
- Only 675 of the nation’s 3,000 counties have ozone monitors in place. With as many as 650 of them (96%) showing violations of the most stringent proposed standard (60 pb).