Presentation on theme: "Water Resources Target Nitrogen loads will be achieved Flexibility for regional solutions Site constraints at Buck Island Site are adequately conditioned."— Presentation transcript:
Water Resources Target Nitrogen loads will be achieved Flexibility for regional solutions Site constraints at Buck Island Site are adequately conditioned Flow neutrality outside of economic growth areas is demonstrated
Regionalization Barnstable Potential sharing of treatment facilities Regional assessment of R8 Hospital Bogs site for effluent disposal Flexibility of Pump stations to accommodate future regional solutions
Regionalization Dennis MEP indicates nearly 100% of septic nitrogen load to upper-Bass River should be removed Mid-Bass River is less nitrogen sensitive Lower-Bass River appears to have more assimilative capacity Bass River will be addressed in subsequent wastewater Planning effort
Effluent Disposal Capacity Buck Island Site R1 Hydrogeologic Investigation and Groundwater Modeling Indicates 0.99 to 1.5 MGD of infiltration capacity Ave BOPeak Phase 1 318,000 gpd418,700 Phase 2 628,000 gpd812, MGD Phase MGD1.40 MGD1.8 MGD CWMP proposes decreasing 4 ft separation to increase infiltration capacity.
Parkers River Watershed
Effluent Disposal Buck Island Site R1 Nitrogen Constraint MEP indicates 1.93 MGD at 3 ppm is the nitrogen loading constraint for Parkers River when Culvert is completed CWMP Phase 1 and 2 will have lower flows with a limit of 7 ppm that operationally will approach 5 ppm. Phase 3 modifications are proposed to achieve a maximum of 5 with an average to approach 3 ppm. Additional Effluent Disposal Capacity will be required beyond Phase 3
Interbasin Transfer of Nitrogen Phase 1 as modified in the SEIR will have a no- net increase to the Greater Parkers River Seine Pond The MEP required septic nitrogen decrease for the Seine Pond Sub-watershed is 59% Seine Pond will receive 25% of effluent nitrogen for an additional 4kg/day at Phase 2 Suggest expediting sewering in Seine Pond subwatershed from Phase 4 to Phase 1 or 2.
Comprehensive Effluent Disposal Effluent Disposal sites in lower and mid Bass River and Nantucket Sound Watersheds have less constraints from nitrogen loading perspective. Additional Site investigation is required for future Phase and Bass River Planning effort
Sewer Service Alternatives Maximize use of R1 site for nitrogen removal Long Pond Groundwater flow and natural attenuation removes approximately 95% of the nitrogen Plashes Pond Natural attenuation should be considered Nantucket Sound No nitrogen limitation
Growth Controls Yarmouth will be seeking 0% SRF Loan which requires flow-neutral controls CWMP uses 16% for buildout + 5 % for additional economic development Commission is working with Town to re- evaluate buildout and buildout flows
Conclusion and Recommendations Single EIR is sufficiently detailed to complete MEPA/Joint Review processSingle EIR is sufficiently detailed to complete MEPA/Joint Review process Subcommittee vote to approve staff report as comment letter to MEPASubcommittee vote to approve staff report as comment letter to MEPA Vote to authorize the Subcommittee Chair to sign a cover letter transmitting the staff report to MEPA on behalf of the CommissionVote to authorize the Subcommittee Chair to sign a cover letter transmitting the staff report to MEPA on behalf of the Commission Comment period closes 8/19/11Comment period closes 8/19/11