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HomeMy WebLinkAboutPresentationBuck Island NOI Presented to Yarmouth Conservation Commission March 21, 2024 Karilyn Heisen, PE, D.WRE CDM Smith Amy Ball, PWS, CWS Horsley Witten Group Plashes Brook August 2023 Nitrogen Impacts in Yarmouth Parkers River Fish Kill Mill Creek Algae Bloom May 2011 4 ▬Water Resource Recovery Facility 100% Design Complete ▬Collection System Groundbreaking for Phase I March 14 Comprehensive Wastewater Management Plan (CWMP) Status ▬Permitting Recharge of Highly Treated Effluent to Aquifer ‐Buck Island Road Hydrogeologic Evaluation Report submitted July 2022 ‐8 potential recharge sites identified in 2011 ‐4 additional recharge sites added for evaluation in 2024 5 ▬Ocean is environmentally sensitive ▬Streams in Yarmouth are small ▬The WRRF removes nitrogen, phosphorus and other wastewater compounds ▬Recharge maintains water levels in wetlands and ponds ▬Recharge improves water levels in areas with lowered groundwater due to pumping Why Recharge to the Groundwater? There can be an overall improvement in wetlands due to improvements in water quality and return of water to the aquifer Example Infiltration Basin 6 ▬Unique site ‐No direct impacts to wetlands (i.e. construction or vegetation removal) ‐Indirect impacts to wetlands by potential increase in maximum water levels ‐Some wetlands are former cranberry bogs ‐Stream flow and local water levels impacted by agricultural ▬Existing site used for disposal of excess reclaimed water from Septage Treatment Facility 99 Buck Island Road NOI Plashes Brook December 2010 7 Water Level Increase 0.29 MGD Recharge ▬Compare mounding to maximum high water with cranberry bogs flooded and irrigation ponds full ‐No impact (groundwater rise < 0.1 foot) if bogs used for drainage ‐Potential groundwater increase between 0.1 and 1 foot if bogs are not used to lower water levels ▬Additional simulation requested by MassDEP (not shown): June conditions with high water table but cranberry bogs and irrigation ponds at average levels ▬Two to three years before recharge begins: ‐Baseline wetlands monitoring (4 locations) ‐Groundwater level monitoring (9 locations) ‐Surface water level monitoring (7 locations) ‐water quality sampling (3 groundwater and 5 surface water locations) ▬Increase in water table will be gradual ▬Model simulations are the worse conditions (high groundwater + high recharge) ‐High effluent recharge period occurs during July and August when water table is low 8 Proposed Monitoring to Identify Adverse Impacts Cranberry Bog Water Control Structure 9 ▬Locations to be established in the field during baseline monitoring 1 location near the cranberry bog irrigation pond (wetland areas #17) near MW-22A 1 location within the Plashes Brook area (wetland area #20) near MW-17 1 location west of the proposed WRRF site (wetland areas #25) near BW-225 1 location south of the proposed WRRF site (wetland area #27) near MW-24 Wetland Hydrology Monitoring Observation Plots 10 ▬Conservation Commission provides input on the wetlands monitoring plan and issues Order of Conditions ▬MassDEP approves Hydrogeological Evaluation (WP-83) for 99 Buck Island Road ▬Town applies for Groundwater Discharge Permit ▬Town bids construction contract – bidding process to start in June 2024 ▬30-day comment period on GWDP after MassDEP issues permit ▬Begin plant construction for Phase 1 – late 2024/early 2025 ▬Baseline monitoring begins 1-year before start-up - 2026 ▬WRRF start-up and recharge begins - 2027 Next Steps Extra Slides 12 Schedule Well Drawdown Impacts 13 Steady-state drawdown associated with 2003 groundwater withdrawals From USGS SIR2004-5181. Stream flows from Parkers River MEP Report 14 Water Level Control Structures 15 Water Level Control Structures 16 Annual and seasonal groundwater variation 17 Average range within one year is ~2.5 ft Range of all observed data is 6.3 ft 18 DEP Wetlands and Mound Extent Mounding > 0.1 ft Mounding > 0.5 ft 19 Wetland Delineation (2008) Recharge Area 20 Infiltration Basins 21 Phase 1 Flows ▬Phase 1 maximum day flow: 1.04 MGD ‐Based on expected initial flows. Does not include build-out ▬Buck Island simulated “maximum month” flow: 0.29 MGD ▬Buck Island permit request: 0.37 MGD ▬Additional flow in Phase 1 likely to be discharged at Bayberry Hills Golf Course and a third alternative site to be identified