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

T.F. Green Airport Improvement ProgramEnvironmental Impact Statement and Final Section 4(f) EvaluationThe methodology used to adjust the FEIS Forecast considered changes in the individual aircraft operatorcategories within the TAF. The TAF is broken down into the following aircraft operator groups; 136 Air Carrier,Air Taxi, General Aviation, and Military (see Appendix E.1, Updated Forecast of Aviation Activity). Therefore, theforecast adjustments accounted for changing percentages of aircraft operator categories at T.F. Green Airportover time. Due to the refined adjustment method to take into account aircraft operator category variations, thedifference in total aircraft operations between the Draft 2010 TAF and the 2010 FEIS No-Action Forecast isconsistent with FAA criteria.Since the DEIS, the FAA identified further wetland impact avoidance and minimization opportunities andmodified the design at the Runway 34 End. Impacts to wetlands were avoided by re-examining the location ofthe Perimeter Road on the east side of Runway 34 along with the design requirements for the end-fire glideslope antenna; 137 a critical part of the system that allows aircraft to make instrument landings on the runway.Runway 34 is equipped with an end-fire antenna. The imaging type glide slope, which is used at the other threerunways at the Airport, has specific site requirements reflected in the previous glide slope area grading designfor Runway 34. Due to the use of an end-fire system at Runway 34, the side slopes along the runway can besteepened beginning at the edge of the RSA. This in turn allowed the Perimeter Road to be shifted closer to theside of Runway 34. This shift brought the Perimeter Road within the glide slope antenna signal zone so the roadwas lowered to prevent vehicles from interfering with the signal. The minimization measures incorporated inthe Runway 34 design presented in this FEIS involved steepening the side slopes adjacent to wetlands from theprevious 4:1 gradient to the present 3:1 slopes. This resulted in a further reduction of wetland impact.3.9.3 FEIS – Summary of Environmental ConsequencesThis section summarizes and compares the environmental consequences and benefits of the No-Action Alternativeand Alternatives B2 and B4 for the relevant environmental resource categories specified in FAA Order 1050.1E.The environmental impacts described below inform the FAA in its identification of the Preferred Alternative.This section includes a discussion of the environmental impacts of Alternatives B2 and B4; any adverseenvironmental effects that cannot be avoided; the relationship between short-term uses of the human environmentand the maintenance and enhancement of long-term productivity; and any irreversible or irretrievablecommitments of resources that would be involved if the T.F. Green Airport Improvement Program isimplemented. Alternatives B2 and B4 would have significant impacts (as significance is defined by FAA) to noise,compatible land use, historical resources, Section 4(f) resources, wetlands, and floodplains. Table 3-12 and thefollowing discussion focuses only on the environmental impacts and program characteristics that differentiate thealternatives from each other and provide a basis for identifying the Preferred Alternative. 138 Some impacts listed inthis section, such as wetlands and floodplains, have been reduced since the DEIS was filed as described inSection 3.9.2, FEIS Impact Analysis. A comparison of the FEIS and DEIS Level 6 findings is provided in Table 3-13.136 FAA Order JO 7210.3V Change 3 effective Aug 27, 2009 Facility Operation and Administration, Chapter 12, section 12-2-2, Categories of Operations, andAppendix 3.137 The end-fire system is a non-image system, and is designed for use in areas where conformance to the imaging type glide slope criteria is impractical. Endfireantenna systems are intended for runways having a limited amount of flat terrain.138 It would be possible to combine Alternative B2 Runway 5-23 configuration with the Alternative B4 Runway 16-34 configuration, however, this combinationwould still require the partial and full relocations of Airport Road. It would be possible to combine the Alternative B2 Runway 16-34 configuration with theAlternative B4 Runway 5-23 configuration, however, this combination would still require the relocation of Main Avenue and partial relocation of Airport Road,and would negatively impact Airport Plaza and the rental car property north of the intersection of Airport and Post Roads.Chapter 3 – Alternatives Analysis 3-41 July 2011\\mawatr\ev\09228.00\reports\FEIS_Final_July_2011\PVD_CH03_Alternatives_JUL_2011.doc