BACKGROUND

The Environmental Protection Agency (EPA) regularly updates its National Ambient Air Quality Standards (NAAQS) for criteria pollutants, classifying areas that do not meet these standards as nonattainment areas. Such designations require states to develop State Implementation Plans (SIPs) that estimate future emissions and outline necessary control measures. The Clean Air Act (CAA) mandates that federally approved projects demonstrate conformity with the applicable SIP, known as General Conformity. Projects exceeding the minimums thresholds must undergo a General Conformity Determination, highlighting the need for accurate emissions inventories in SIPs.

Since the release of ACRP Report 84: Guidebook for Preparing Airport Emissions Inventories for State Implementation Plans (2013), the EPA has lowered the NAAQS for ozone and PM2.5. This has resulted in an increased number of nonattainment areas, subjecting airport improvement projects to greater scrutiny. As airport operations are projected to grow, it is crucial that SIPs accurately account for the resulting emissions, particularly for projects like new runways and terminals.

Research is needed to update ACRP Report 84: Guidebook for Preparing Airport Emissions Inventories for State Implementation Plans and for airport operators,  inside and outside attainment areas, who are more frequently conducting inventories for reasons beyond SIP, such as voluntary commitments, environmental, social, and governance (ESG) reporting, and state and local initiatives.

OBJECTIVE

The objective of this research is to develop a guide for US airports on how to develop emissions inventories for purposes beyond federal actions, while building on and updating ACRP Report 84: Guidebook for Preparing Airport Emissions Inventories for State Implementation Plans.

The guide should include at a minimum, the following:

• A discussion of the various drivers on why an airport may develop an emissions inventory such as federal, state, local requirements (including the nonattainment status of a region), and voluntary commitments;
• An overview of the types of pollutant emissions that may be quantified, including criteria pollutants within nonattainment areas and attainment areas, hazardous air pollutants, and greenhouse gasses;
• A list of applicable tools and a discussion on how airports can use them to complete emissions inventories;
• A discussion of different approaches based on the relative orders of complexity and how to choose between them based on suitability;
• A discussion of how emissions inventories for nonattainment areas can integrate into a SIP and help airports meet general conformity requirements; and
• A discussion of SIP coordination strategies and best practices.

RESEARCH PLAN

The research plan shall include at a minimum, the appropriate interim deliverables for ACRP review and approval, that include:

• A summary of relevant research, including ACRP publications, emissions inventory tools (including data needs), and other relevant guidance such as the FAA Aviation Emissions and Air Quality Handbook;
• A gap analysis of ACRP Report 84: Guidebook for Preparing Airport Emissions Inventories for State Implementation Plans, along with a discussion of gaps relative to the broadened research objective;
• A summary of changes in issues such as policies, regulations, and industry practices; and
• An interim report to include research results to date, analysis of results, next steps, an annotated outline for the guide, and potential follow-on research ideas to be developed into problem statements.

The research plan should also include, at a minimum, checkpoints with the ACRP panel including:

• A kick-off web meeting to be held within 1 month of the Notice to Proceed;
• A web meeting to discuss summary; and
• One face-to-face interim deliverable review meeting, as well as web-enabled teleconferences tied to the panel review and ACRP approval of other interim deliverables deemed appropriate.

The final deliverables will include: 

• The guide; 
• Research Team’s Final Report documenting all research steps, results, and analysis;
• The Summary of Key Findings; 
• The Further Recommended Research Memo; and 
• A technical memo titled “Implementation of Research Findings and Products”.

STATUS: Proposals have been received in response to the RFP. The project panel will meet to select a contractor to perform the work.