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

T.F. Green Airport Improvement ProgramEnvironmental Impact Statement and Final Section 4(f) Evaluationin a net increase in roadway and parking area (impervious surfaces), with a 17.8-acre net increase, andAlternative B4 would result in no net change in roadway and parking area (impervious surfaces).Alternative B2 would incorporate three types of control measures to minimize changes to hydrology and waterquality: designed stormwater controls; operations and maintenance procedures; and construction-period controlmeasures, as described in Section 6.10, Water Quality, for Alternative B4. The conceptual design for AlternativeB2 is intended to comply with the most recent draft of the Rhode Island Stormwater Design and InstallationStandards Manual. No mitigation is required aside from compliance with RIDEM standards.6.21.10 Fish, Wildlife, and PlantsBased on the impact analysis presented in Chapter 5, Environmental Consequences, Alternative B2 would notsignificantly impact fish, wildlife, and plants. While the habitat for two state-listed species were observed in theProject Area (the pine barrens tiger beetle, and sickle-leaved golden aster), these habitats would not be impactedby Alternative B2. Alternative B2 would impact a 142-linear foot segment of Buckeye Brook north of LakeshoreDrive including the extension of an existing culvert by 30 linear feet. In order to avoid obstructing river herringpassage to spawning areas in Spring Green Pond, a new culvert would be designed to maintain passage. Therelocated stream channel would also be designed to promote fish passage to and from Spring Green Pond.Similar to Alternative B4, Alternative B2 avoids impact to important plant and wildlife habitat south ofRunway 34 and would not require additional mitigation.6.21.11 Threatened and Endangered SpeciesThere are no federally listed species of concern or threatened or endangered species within the Project Area and,therefore, there would be no significant impacts to threatened or endangered species as a result of theT.F. Green Airport Improvement Program. No mitigation is required.6.21.12 FloodplainsAlternative B2 would result in significant impacts as it would require filling of approximately 0.5 acres offloodplain. Alternative B2 would constitute a “significant encroachment” since it would cause adverse impactson natural and beneficial floodplain values. Alternative B2 would impact 0.7 acres less floodplain thanAlternative B4, and therefore less mitigation would be required.Alternative B2 impacts Lower Buckeye Brook through the construction of a new access road to the AMF andconstruction of the glide slope critical area east of the Runway 23 End. Partial mitigation for fill placed in theLower Buckeye Brook floodplain between Airport Road and Lakeshore Drive would be achieved by theremoval of an existing roadway fill section in this floodplain that is no longer needed by the Airport. Floodingof Lakeshore Drive would also be mitigated by replacing the existing, restrictive culvert under Lakeshore Drivewith a new structure with greater capacity. Additional mitigation measures would be implemented in BuckeyeBrook through the removal of existing roadway fill sections between Airport Road and Lakeshore Drive northof Warwick Pond (Wetland Mitigation Site 3) and with the construction of Wetland Mitigation Site 1, describedin Section 6.9, Wetlands and Waterways.Chapter 6 – Mitigation 6-51 July 2011\\Mawatr\ev\09228.00\reports\FEIS_Final_July_2011\PVD_CH06_Mitigation_JUL_2011.doc