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EPA Proposes to Redesignate Ozone Nonattainment Areas

As published in the Federal Register on 08/27/2015, EPA is proposing to redesignate 36 Ozone Nonattainment Areas, including Atlanta.  Based on the 2012-2014 design value, EPA determined that Atlanta did not attain the 2008 ozone NAAQS by July 20, 2015, thereby triggering a “bump up” in nonattainment classification from marginal to moderate.  The new attainment date is July 20, 2018.  The proposed SIP submittal due date is January 1, 2017 or March 1, 2017 (comment solicited).  Several federal standards, including CSAPR, Tier 3 vehicle standards, and Boiler MACT, are expected to support attainment efforts.  However, state agencies could find that additional NOx or VOC control measures (RACT rules) are needed.  Georgia EPD has indicated that it intends to certify 2013-2015 ozone monitoring data in support of a request to redesignate to attainment.

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EPA Proposed Amendments to MSW Landfill Air Emissions Standards

On 08/14/2015, EPA proposed amendments to emissions standards for MSW landfills.

Fact Sheet for Existing Landfills:


  • The agency is proposing to update the emissions threshold that triggers a requirement to install landfill gas collection and control systems. That annual threshold, currently set at 50 metric tons (written as megagrams in the proposal) of nonmethane organic compounds, would change to 34 metric tons for active landfills under the proposed guidelines. This is the same threshold EPA is proposing for new landfills. Closed landfills would remain subject to the current threshold of 50 metric tons per year.
  • Landfills subject to the proposed guidelines would have 30 months after reaching the emissions threshold to install and begin operating a gas collection and control system.
  • Landfill owners/operators with a gas collection and control system would to be required to expand that system into new areas of the landfill within five years for active areas, and two years for areas that are closed or at final grade.

Fact Sheet for New, Modified, and Reconstructed Landfills:

EPA Site:

For more information, contact your EPS consultant.

Proposed Revisions to EPA’s Guideline on Air Quality Models

On 07/29/2015, EPA’s proposed revision to the air quality modeling guideline (Appendix W to 40 CFR Part 51) was published.

Appendix W Factsheet:


  • Proposed enhancements to the scientific formulation of the preferred nearfield dispersion model, AERMOD, including modeling techniques to address the secondary chemical formation of fine particle and ozone pollution from direct, single source emissions of pollutants that form them such as sulfur dioxide, oxides of nitrogen, volatile organic compounds. (See details below)
  • Proposed streamlining of resources necessary to conduct regulatory modeling with AERMOD by incorporating model algorithms from the Buoyant Line and Point Source (BLP) model and replacing the CALINE3 model used for mobile source applications including fine particle pollution (PM2.5, PM10), and carbon monoxide (CO) hot-spot analyses.
  • Remove CALPUFF as a preferred model for long range air quality assessments and recommending its use as a screening technique along with other Lagrangian models for addressing PSD increment beyond 50 km from a new or modifying source. This proposed change does not affect the EPA’s recommendation in the 2005 BART Guidelines to use CALPUFF in the BART determination process.

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AERMOD Dispersion Model Version 15181 Released

On 07/24/2015, EPA released an updated version of the AERMOD model. Key technical changes in the new version are as follows:

  • Includes option in AERMET to adjust the surface friction velocity (u*) to address issues with AERMOD model over prediction under stable, low wind speed conditions.
  • Includes a low wind option in AERMOD to address issues with model over prediction under low wind speed conditions. The low wind option will increase the minimum value of the lateral turbulence intensity (sigma-v) from 0.2 to 0.3 and adjusts the dispersion coefficient to account for the effects of horizontal plume meander on the plume centerline concentration.
  • Modifications to AERMOD formulation to address issues with over prediction for applications involving relatively tall stacks located near relatively small urban areas.
  • Includes regulatory default options to address plume rise for horizontal and capped stacks.
  • Includes buoyant line source option based on the BLP model.
  • Updates to the NO2 Tier 2 and Tier 3 screening techniques coded within AERMOD for assessments related to 1 hour NO2 standards. Tier 2 technique will be ARM2 which is based on hourly measurements of the NO2 to NOx ratios and provides more detailed estimates of this ratio based on the total NOx present. For Tier 3 technique, the existing detailed screening options of the Ozone Limiting Method (OLM) and PVMRM which have been  available as non-regulatory, non-default options in AERMOD for many years is formally incorporated as regulatory options.

Please contact your EPS consultant for more information.

Reconsideration and Proposed Amendments to Boiler Rules Published

On 01/21/2015, the reconsideration and proposed amendments to the Boiler MACT and the Boiler Area Source NESHAP were published in the Federal Register:

Boiler MACT:

Proposed Rule:

Fact Sheet:

Redline/Strikeout Version:

Boiler Area Source NESHAP:

Proposed Rule:

Fact Sheet:

Redline/Strikeout Version:

Comments will be accepted until March 9, 2015.

EPA Proposes to Tighten Ozone Standards

On 11/25/14, EPA proposed to tighten the ground-level ozone standards to within a range of 65 to 70 ppb or possibly as low as 60 ppb, as compared to the current NAAQS of 75 ppb.  Public comments will be accepted for 90 days after publication in the Federal Register.  And, EPA plans to issue the final revised ozone NAAQS by 10/01/15.

Proposed Rule:

More information:

EPA Issues Ministerial Actions to Implement CSAPR

On 11/21/14, EPA issued two ministerial actions to implement the Cross State Air Pollution Rule (CSAPR) beginning on January 1, 2015.  The implementation of CSAPR will sunset the Clean Air Interstate Rule (CAIR), which is a similar cap-and-trade based program.  CSAPR requires the covered 28 states to limit SO2 and/or NOx emissions from electric generating units (EGUs) on a state-wide basis, with the goal of reducing contributions to fine particulate matter (PM2.5) and ground-level ozone in other states.  CSAPR had been stayed by the D.C Circuit of the U.S. Court of Appeals since 2011, but on 10/23/14, the Court ordered that EPA’s motion to lift the stay be granted.  To reflect the three-year delay in implementation, EPA is issuing final rules that toll the implementation dates to allign with a January 1, 2015 start date for Phase 1 and 2017 for Phase 2.

CSAPR Interim Final Rule:

NODA for CSAPR Unit Level Allocations:


EPA Web Site:

EPA Releases Revised Framework for Biogenic CO2 Accounting

On 11/19/14, EPA released a revised framework for assessing biogenic CO2 emissions from stationary sources.

  • For the Clean Power Plan, EPA expects to recognize biogenic CO2 emissions and climate poly benefits of waste-derived and certain forest-derived industrial byproduct feedstocks, support states’ efforts in using biomass power to met the CPP goals.  EPA also mentions that sustainably-derived agricultural and forest-derived feedstocks may also be an approvable element of CPP compliance plans.
  • For PSD, EPA plans rule revisions to exempt from BACT requirements waste-derived feedstocks and non-waste biogenic feedstocks derived from sustainable forest or agricultural practices.  This is based on EPA’s position that biogenic CO2 emissions are likely to have minimal or no net atmostpheric contributions of CO2 or even reduce such impacts when compared to an alternate fate of disposal.

Janet McCabe Memo:

EPA Framework Document:

EPA website:

GA EPD Issues GHG Permitting Policy to Address Supreme Court Action

On 07/10/14, GA EPD posted a memo discussing the agency’s policy with respect to the GHG Tailoring Rule and the U.S. Supreme Court’s recent ruling:

Key points: 

  • For biomass facilities, the July 20, 2014 deadline to begin actual construction (per the biogenic deferral) is no longer applicable.
  • For in-progress and new permitting actions, EPD will not implement GHG PSD permitting (for “non-anyway” sources) or GHG Title V permitting.
  • After the 11th Circuit U.S. Court of Appeals vacates the Tailoring Rule provisions:
    • Existing sources may apply to have GHG-related PSD requirements (for “non-anyway” sources) removed from their permits.
    • Existing sources required to have Title V permits solely due to GHGs may apply to become Title V minor.
  • EPD will continue to use the 75,000 ton/yr CO2e de minimis level for “anyway sources” for PSD GHG BACT purposes.

For questions regarding impact on issued permits or pending permitting actions, contact your EPS consultant.

Supreme Court Strikes Down GHG PSD and Title V Authority

Today (06/23/14), the U.S. Supreme Court issued a 5-4 ruling that eliminates EPA’s authority to require PSD and Title V permits based on GHG emissions.


Some key findings of the Court:


  • The Clean Air Act does not compel EPA to interpret the definition of “air pollutant” such that GHGs must be subject to the PSD and Title V permitting programs.  This is a reversal of the Court of Appeals decision.
  • EPA lacked authority to “tailor” the PSD and Title V major source thresholds for GHGs.
  • EPA reasonably interpreted the Clean Air Act to require GHG BACT for “anyway sources” – those facilities that triggered PSD for conventional criteria pollutants (e.g., NOx).
  • EPA may establish a de minimis level below which BACT is not required for GHGs – again, only for “anyway sources”.  And, the existing threshold for modified sources (75,000 tons/yr CO2e) was not established as a de minimis level for BACT but could be set as a de minimis level with EPA justification.

The ruling does not appear to impact other GHG regulatory efforts, including the recently-proposed performance standards for power plants and mobile source emissions standards.

Some questions arise:

  • How will EPA and state agencies react to the ruling?  When will regulations (40 CFR 52.21) be amended?
  • Can state agencies waive GHG PSD and Title V permitting immediately?  Or, do the regulations (SIPs) need to be amended first?
  • When will EPA issue a GHG de minimis level for “anyway sources”?  Will they propose to keep the 75,000 ton/yr CO2e threshold?

The decision is available here: