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

T.F. Green Airport Improvement ProgramEnvironmental Impact Statement and Final Section 4(f) Evaluation5.11.4.1 No-Action AlternativeThe No-Action Alternative would include improvements to water quality in the Buckeye Brook North,Tuscatucket Brook, and Callahan Brook watersheds by decreasing impervious surfaces through the removal ofhouses associated with the Current Part 150 VLAP. This would also reduce peak runoff rates in thosewatersheds. The No-Action Alternative would include mitigation measures for the full length taxiway M withinthe Buckeye Brook South drainage area. The No-Action improvements would be designed to meet statestormwater requirements and would not adversely affect water quality in Buckeye Brook.Table 5-111 shows the annual pollutant loading within the affected drainage areas for the No-Action Alternative.Infiltrating stormwater BMPs and pervious surfaces located between impervious surfaces, such as taxiways andrunways, and the stormwater collection system would be implemented to effectively reduce pollutant loadingimpacts and would not adversely affect water quality in receiving waters.Table 5-111Annual Pollutant Loading by Drainage Area 1 (No-Action Alternative)Pollutant 2Drainage Area TSS P N Cu Pb Zn BOD COD BacteriaBuckeye Brook North 46,061 77 706 0 11 16 2,457 30,708 522,029Warwick Pond 1,870 3 29 0 0 1 100 1,247 21,194Buckeye Brook South 35,077 58 538 0 8 12 1,871 23,385 397,537Mill Cove (cumulative) 3 83,008 138 1,273 0 19 29 4,428 55,340 940,760Tuscatucket Brook 10,973 18 168 0 3 4 585 7,316 124,366Callahan Brook 9,871 16 151 0 2 3 526 6,581 111,876Brush Neck Cove (cumulative) 4 20,844 172 1,592 0 24 36 5,539 69,237 1,177,002Total 103,852 206 1,911 0 29 43 6,650 83,134 1,413,244Source: VHB, Inc.1 A Highway Land Use Category was assumed the most appropriate Land Use Category for T.F. Green to determine the Event Mean Concentrations (EMCs)values. Other categories include Residential, Commercial, Industrial, and Undeveloped/Rural.2 The pollutants loading listed in this table represent the potential annual loading rate for the five drainage areas, totaling 1,360 acres, without the installation ofstormwater BMPs, where TSS is Total Suspended Solids, P is Phosphorus, N is Nitrogen, Cu is Copper, Pb is Lead, Zn is Zinc, BOD is Biological OxygenDemand, and COD is Chemical Oxygen Demand. Pollutants were calculated using the Simple Method (Schuster, 1987) which requires estimates of annualrainfall, site impervious cover, land use type, and pollutant loading coefficients based on land use. Totals are rounded.3 The Mill Cove drainage area consists of the combined Buckeye Brook North, Warwick Pond, and Buckeye Brook South drainage areas evaluated in this analysis.4 The Brush Neck Cove drainage area consists of the combined Tuscatucket Brook and Callahan Brook drainage areas evaluated in this analysis.The Airport completed construction of a consolidated glycol dispensing and blending facility in 2009. Theblending facility is expected to reduce the use of glycol at the Airport by up to 30 percent. Glycol-impactedstormwater will be controlled in accordance with the RIPDES permit and MOA executed on February 19, 2009,and Annual Deicing Management Program Plan, collectively referred to as the “RIPDES permit.” Under theRIPDES permit, RIAC will design and install a new deicer management system that will further reduce theamount of glycol-impacted stormwater that may be discharged to the receiving waters. The deicer managementsystem will be constructed independent of the proposed Improvement Program and is included in theNo-Action Alternative.Chapter 5 - Environmental Consequences 5-213 July 2011\\mawatr\ev\09228.00\reports\FEIS_Final_July_2011\PVD_CH05_Environmental_Cons_JUL_2011.doc