Facilities received the letter because LDEQ must develop a State Implementation Plan (SIP) for the Regional Haze Planning Period II. This SIP must demonstrate reasonable progress toward achieving natural visibility conditions in Federal Class I areas during the period between 2018 and 2028. LDEQ must develop a long term strategy for reducing emissions of key pollutants and sources impacting visibly impairment by 2064. Facilities were evaluated and selected for four factor analysis based on their emissions and location relative to the Class I area for contribution to light extinction at the Class I area. The purpose of a four factor analysis is to determine if there are emission control options that, if implemented by a facility, could be used to attain reasonable progress toward the visibility goals set forth in the SIP.
The Regional Haze Rule establishes four factors by which a state must consider potential control measures for the long-term strategy. The four factor analysis involves assessing potential emission controls technologies against four statutory factors:
(1) Cost of compliance
(2) Time necessary for compliance
(3) Energy and non-air quality environmental impacts of compliance
(4) Remaining useful life of existing sources that contribute to visibility impairment
All four factor analysis should be prepared using the guidance provided in the following documents.
Yes, a facility must evaluate every source of NOX and SO2. If controls are currently in place, please evaluate the source and document the existing controls.
LDEQ will not provide an example of a four-factor analysis. Please reference EPA’s Guidance on Regional Haze State Implementation Plans for the Second Implementation Period for assistance preparing your analysis.
LDEQ must have a completed draft of the SIP by March 2021 to allow for a 60 day comment period, and at this time has no plans to hold a stakeholder meeting. A public hearing will be held, if requested, during the comment period.
Alternative technology and vendor estimates can be used as long as the estimate is fully documented and the alternative technology will provide controls that are at least as efficient as the controls listed in the EPA Air Pollution Control Cost Manual.