[Federal Register Volume 63, Number 70 (Monday, April 13, 1998)] [Notices] [Pages 18068-18069] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 98-9641] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration [Docket No. 29194] RIN 2120-AC22 Emissions and Dispersion Modeling System Policy for Airport Air Quality Analysis; Interim Guidance to FAA Orders 1050.1D and 5050.4A AGENCY: Federal Aviation Administration, DOT. ACTION: Policy Statement. ----------------------------------------------------------------------- SUMMARY: This document provides a statement of Federal Aviation Administration (FAA) policy concerning the required use of the FAA Emissions and Dispersion Modeling System (EDMS) to assess the air quality impacts of proposed airport development projects. To date, the EDMS has been considered an FAA preferred model for airport air quality analysis. The policy statement is intended to ensure consistency and quality of analysis performed to assess the air quality impacts of airport emission sources for purposes of complying with the National Environmental Policy Act of 1969, as amended, 42 U.S.C. 4321 et seq. (NEPA) and the Clean Air Act as amended, 42 U.S.C. 7401, 7506(c) general conformity (general conformity) requirements. EFFECTIVE DATE: April 13, 1998. FOR FURTHER INFORMATION CONTACT: Ms. Julie Ann Draper, Analysis and Engineering Branch (AEE-120), Technology Division, Office of Environment and Energy, Federal Aviation Administration, 800 Independence Avenue, SW., Washington, DC 20591, telephone (202) 267-3494. SUPPLEMENTARY INFORMATION: The EDMS was developed by the FAA in cooperation with the U.S. Air Force (USAF) in the mid-1980's as a complex source microcomputer model to assess the air quality impacts of proposed airport development projects. It has since been the FAA preferred model for airport air quality analysis. On July 20, 1993, the Environmental Protection Agency (EPA) accepted the EDMS as a formal EPA ``Preferred Guideline'' model for use in civil airports and [[Page 18069]] military bases. In response to the growing needs of the air quality analysis community and changes in regulations, the FAA in cooperation with the USAF re-engineered and enhanced EDMS in 1997 to create EDMS Version 3.0. EDMS Version 3.0 was built under the guidance of a government and industry advisory board composed of experts from the scientific, environmental policy, and analysis fields. The FAA provides guidance on the use of EDMS in FAA Report No. AEE- AEE-97-03, ``Air Quality Procedures for Civilian Airports and Air Force Bases,'' which updates and replaces the original version of the handbook, FAA Report No. FAA-82-21. The FAA is taking this opportunity to identify EDMS as the required model to perform the air quality analyses for aviation emission sources from airport projects instead of the preferred model, as stated in the FAA's ``Air Quality Procedures for Civilian Airports and Air Force Bases.'' This policy statement will serve as the interim written document until the revised FAA Orders 1050, Policies and Procedures for Considering Environmental Impacts, and 5050, Airport Environmental Handbook, are published. Policy Statement EDMS is designed to assess the air quality impacts of airport emission sources, particularly aviation sources, which consist of aircraft, auxiliary power units, and ground support equipment. EDMS also offers the capability to model other airport emission sources that are not aviation-specific, such as power plants, fuel storage tanks, and ground access vehicles. Except for air toxics or where advance written approval has been granted to use an equivalent methodology and computer model by the FAA Office of Environment and Energy (AEE-120), the air quality analyses for aviation emission sources from airport projects conducted to satisfy NEPA and general conformity requirements under the Clean Air Act must be prepared using the most recent EDMS model available at the start of the environmental analysis process. In the event that EDMS is updated after the environmental analysis process is underway, the updated version of EDMS may be used to provide additional disclosure concerning air quality but use is not required. A complete description of all inputs, particularly the specification of non-default data, should be included in the documentation of the air quality analysis for purposes of complying with NEPA and general conformity requirements. Users also must provide one copy of EDMS input files used in the analysis and the corresponding output files to the FAA responsible official on magnetic media specified by the FAA responsible official. As stated above, EDMS currently is not designed to perform air toxic analyses for aviation sources, and may be supplemented with other air toxic methodology and models in consultation with the appropriate FAA regional program office. Use of supplemental methodology and models for more refined analysis of non-aviation sources also is permitted in consultation with the appropriate FAA regional program office. This policy is being issued in order to ensure consistency and quality of analysis performed to assess the air quality impacts of airport emission sources for purposes of complying with NEPA and general conformity requirements. Issued in Washington, DC, on April 6, 1998. Paul R. Dykeman, Deputy Director of Environment and Energy. [FR Doc. 98-9641 Filed 4-10-98; 8:45 am] BILLING CODE 4910-13-M