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

T.F. Green Airport Improvement ProgramEnvironmental Impact Statement and Final Section 4(f) EvaluationDEIS Appendix E, Alternatives Analysis provides a full description of the project elements evaluated under theLevel 2 Screening.3.4.1 Refinement of AlternativesSelected Candidate Alternatives that could meet FAA’s standard design criteria were refined based onevaluation of FAA safety requirements, size and design requirements, and through consideration of physicalconstraints.3.4.1.1 Runway Safety Area RefinementsThe FAA’s objective is to improve existing, physically constrained runways in order to enhance operationalsafety. The FAA encourages the design of new runway extensions to incorporate the full 1,000-foot turf RSA, inorder to conform to the design requirements. In certain circumstances such as when there are severe physicalconstraints, and when it is impractical to provide a full 1,000-foot RSA, FAA Order 5200.8 and FAA AdvisoryCircular (AC) 150/5220-22A establish a procedure that enables the consideration of EMAS as an option to provideequivalent levels of safety. EMAS is a soft concrete material that can safely decelerate an aircraft to a complete stopwith minimal damage if the aircraft overshoots the runway. It is typically placed within a 500-foot wide safety areathat extends 600 feet beyond the end of the runway, and allows for a standard RSA that is less than 1,000-feet long.The use of EMAS was considered for the RSAs for each of the runway ends of Runway 16-34 and Runway 5-23.3.4.1.2 Runway 5-23 Extension Runway Length RefinementsBased on the standard methodology for determining the recommended runway length provided in FAAAC 150/5325-4B, a primary runway length of 10,700 feet is recommended at T.F. Green Airport. 100 However,because of surrounding land use, environmental, and infrastructure constraints, a 10,700-foot runway isimpractical to implement at T.F. Green Airport. Therefore, an “operationally preferred” 101 runway length of9,350 feet was identified using a modified methodology provided in FAA AC 150/5325-4B. The operationallypreferred runway length considered reductions in belly cargo weight for aircraft types that demand longerrunways. DEIS Appendix E, Alternatives Analysis Attachment E.A.1, Runway Length Analysis provides a detaileddiscussion of the methodology used to determine the operationally preferred runway length.3.4.1.3 Supporting Off-Airport Roadway RefinementsThe Runway 16-34 Safety options and the Runway 5-23 Extension options would impact Post Road,Airport Road, or Main Avenue due to off-Airport roadway configurations. Options for maintaining traffic flowand continuity on each of these roadways were evaluated, and options were eliminated if they were found to be not reasonable or feasible.• Post Road is a densely-developed north-south urban roadway. Preliminary Alternatives evaluated forPost Road included constructing a tunnel, realigning the road, or constructing the road in a new location.These options were found to not be reasonable and feasible due to excessive property, business, and trafficimpacts. Therefore the Preliminary Alternatives involving realignment of Post Road were eliminated fromfurther consideration.100 Based on the runway length requirements of the B767-300 (the Airport’s critical design aircraft) according to the aircraft manufacturer’s specifications manual.101 “Operationally preferred” runway length refers to an adjustment in the recommended runway length due to extenuating circumstances (such as surroundingland use, environmental, and infrastructure constraints) that still meets the runway length needs of the existing and future fleet mix.Chapter 3 – Alternatives Analysis 3-11 July 2011\\mawatr\ev\09228.00\reports\FEIS_Final_July_2011\PVD_CH03_Alternatives_JUL_2011.doc