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

T.F. Green Airport Improvement ProgramEnvironmental Impact Statement and Final Section 4(f) Evaluation3.6 Level 4 Screening - Refined Combined AlternativesThe Level 4 Screening process included two steps: advancing each of the five IP Options to a 30 percentengineering design level in order to more accurately evaluate the full range of environmental impacts; andassess practicability based on construction logistics and cost. The design was conducted to a level at which thelimit of impact and areas of pavement could be calculated. As noted in Section 3.5, each of the IP Options meetsthe purpose to the same degree. Each of the IP Options includes all of the T.F. Green Airport ImprovementProgram elements and a proposed extension of Runway 5-23 to 9,350 feet. In the Level 4 Screening, FAA andRIAC evaluated each of the IP Options to determine whether it would be practicable on the basis of:• The impacts to the aquatic ecosystem; 103• Other significant adverse environmental consequences;• Operational safety; and• Cost.A major cost item was the construction of the Main Avenue tunnel, which was estimated to be approximately$112 million, and was included in all IP Options except for IP Option B. FAA determined that puttingMain Avenue in a tunnel, although constructible, would not be practicable for public safety considerations 104and cost. Therefore, all IP Options with the Main Avenue tunnel were eliminated from further consideration.The only IP Option that does not include a Main Avenue tunnel was IP Option B, which moved forward in thealternatives consideration.Of the three Integrated Cargo Facility site locations, Site 3 was operationally preferred and would not impactwetlands, and thus was retained for further environmental analysis. Refer to DEIS Appendix E, AlternativesAnalysis for the full Level 4 Screening practicability analysis.Based on the Level 4 screening analysis, FAA dismissed four of the Level 4 Alternatives (IP Options A, C, D,and E) from further consideration because they would not be practicable to construct based on environmentalimpacts, community impacts, and cost. 105 Integrated Cargo Facility Sites 1 and 2 were eliminated from furtheranalysis because they would not be practicable to construct due to airside operational safety concerns. Inaddition Site 1 would impact wetlands. The Site 3 location of the Integrated Cargo Facility was carried forward.Table 3-4 summarizes the results of the Level 4 screening analysis.The No-Action Alternative and IP Option B were carried forward into the Level 5 screening because based on theLevel 4 screening, they were found to be practicable and IP Option B would meet the project Purpose and Need.Within the Level 5 screening process, four steps were undertaken as described in the following section.103 Impacts to the aquatic ecosystem were used as a screening criteria because the Clean Water Act protects these resources and a permit from the USACEwould be required if the IP Options would significantly impact wetlands.104 Currently, the Rhode Island Department of Transportation (RIDOT) does not own or operate any tunnels, and expressed concern about public safety.105 For cost and impacts of the Level 4 Alternatives, see DEIS Appendix E, Alternatives Analysis Tables E.6-1 and E.6-2.Chapter 3 – Alternatives Analysis 3-15 July 2011\\mawatr\ev\09228.00\reports\FEIS_Final_July_2011\PVD_CH03_Alternatives_JUL_2011.doc