T.F. Green Airport Improvement Program - FEIS Chapters - PVD

T.F. Green Airport Improvement ProgramEnvironmental Impact Statement and Final Section 4(f) Evaluationairports, such as T.F. Green, in which there are more than 1.3 million annual enplanements. As T.F. Green Airportexceeds this threshold, a NAAQS Assessment has been performed for the Improvement Program to determinewhether the pollutant concentrations would exceed the NAAQS. Additionally, as the State of Rhode Island is in nonattainmentfor ozone (0 3) a General Conformity Assessment has been performed to determine if net emissions ofozone exceed the General Conformity threshold levels or are otherwise regionally significant.The overall approach for conducting the air quality assessment, including the objectives, methodologies, andintended outcomes were initially reviewed by the RIDEM prior to undertaking the analyses. 193 In general, the airquality assessment includes the following:• Emissions Inventory – The purpose of an emissions inventory is to quantify the amounts (i.e., total mass) ofair emissions (associated with the Airport, by emission source and pollutant type). Consistent with thisapproach, the sources of emissions included in the inventory are identified as aircraft, GSE/APUs, on- andoff-site motor vehicle operations and airport-related stationary sources and fuel storage facilities.• Atmospheric Dispersion Analysis – The purpose of the atmospheric dispersion analysis is to convert theemissions inventory results for CO, NO x, and PM 10/2.5to ambient (i.e., outdoor) concentrations at receptorslocated on the Airport, around the perimeter, and in the neighboring community. This is achieved bycombining the Emissions and Dispersion Modeling System (EDMS) emissions inventory output with actualhourly meteorological data and geographical information from the Airport area. Background pollutantlevels are added to the results to account for the contributions from non-airport, regional and naturalsources. The results are then directly compared to the NAAQS.• CO “Hot-Spot” Analysis – The purpose of this analysis is to predict ambient levels of CO in the vicinity ofroadway intersections, both on and off the Airport. Seven intersections were analyzed and selected basedon their proximity to the Airport and based on the surface transportation traffic analysis. The modeling wasconducted under simulated worst-case meteorological conditions (i.e., low wind speeds, stable atmosphericconditions, and low ambient temperatures) and the results are directly compared to the NAAQS for CO.• HAPs Emissions Inventory – HAPs are a category of air emissions distinct from the EPA criteria airpollutants and for which there are no NAAQS. The HAPs emissions inventory includes aircraft, GSE/APU,motor vehicle operations, and on-site stationary sources.Baseline conditions are based upon 2004 aircraft operations activity levels, aircraft fleet mix and operationaltimes for landing; take-off; climb-out; and ground-based taxi-in, taxi-out and delay periods. 194 GSE emissions arealso based upon the aircraft fleet mix and GSE operational characteristics at the Airport in 2004.4.6.1.1 Air Quality Study AreaThe Airport is located in a designated non-attainment area for the criteria pollutant O 3. Because O 3is a regionalpollutant, the non-attainment area designation is not confined to the Providence and Warwick area, butincludes the entire State of Rhode Island and extends into the neighboring states of Connecticut and193 RIDEM approved the Air Quality Assessment Protocol except for the exclusion of a health risk assessment based on hazardous air pollutant emissionsand dispersion modeling.194 The year 2004 airport operational levels are used in the air quality assessment for consistency with the noise, surface transportation, and other sections of the EIS.Chapter 4 – Affected Environment 4-35 July 2011\\mawatr\ev\09228.00\reports\FEIS_Final_July_2011\PVD_CH04_Affected_Env_JUL_2011.doc