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HomeMy WebLinkAboutadditional model revisions 21Feb2023 Updated Model and Site Capacity 22-WP83-005-APPdocx.docx Memorandum To: Joe Cerutti (MassDEP), Ian Jarvis (MassDEP) From: Karilyn Heisen, PE, D.WRE (CDM Smith) Date: February 22, 2022 Subject: Yarmouth, MA - Buck Island Hydrogeologic Evaluation Application 22-WP83-005- APP –Groundwater Model Updates and Revised Site Capacity Executive Summary Per the memorandum provided on January 12, 2023 and our discussion on January 27, 2023, modifications were made to the groundwater flow model used for the Buck Island recharge site in Yarmouth, Massachusetts, as documented in the 2011 Hydrogeologic Evaluation. This memorandum summarizes the modifications, model calibration and revised discharge capacity estimate. This memorandum beings with a brief executive summary, list of attached figures, tables and photographs and then provides details on model updates and calibration, simulated recharge capacity and references. During model recalibration, it became evident that the water levels on-site are strongly influenced by the adjacent cranberry bogs to the west and to the north and the Plashes Brook and adjacent wetlands to the east and south. The January 12 memorandum indicated that the model would be re- calibrated by adjusting conductivity in drain cells which represent the bogs, brook and wetland features. During model calibration, it became apparent that operation of the cranberry bogs to the west and north likely increases the natural water levels in the aquifer. Therefore, the cranberry bogs were simulated using river model boundaries with fixed stages. This allows these cells to both recharge and discharge water to the aquifer. This is consistent with application of irrigation water to cultivate cranberries. Water level elevations for the bogs were estimated from the 1984 Facilities Plan and existing surface data. Proposed water level measurement locations in the cranberry bogs are included in the groundwater and surface water monitoring plan submitted with the Hydrogeologic Evaluation 22-WP83-005-APP. Overall, the use of the river cells (MODFLOW RIV package) improved model calibration to the observed long-term average head data, particularly at the northern and western portion of the site. Recharge from precipitation and hydraulic conductivity values were unchanged from the groundwater model documented in the 2011 Hydrogeologic Evaluation. Drain conductance values for Plashes Brook and associated wetlands were adjusted to match water levels adjacent to the brook and match the estimated flow data from the Massachusetts Estuary Project (MEP) (Figure IV- 9 from MEP 2010). 28Sep2023 Proposed Permit Approach.docx Memorandum To: Gerard Martin, Deputy Regional Director, MassDEP SERO From: Karilyn Heisen and David Young – CDM Smith Date: September 29, 2023 Subject: Yarmouth, MA – Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP – Proposed Pathway Forward CDM Smith, on behalf of the Town of Yarmouth, filed a Hydrogeologic Evaluation Report with the Massachusetts Department of Environmental Protection (MassDEP) for the proposed 99 Buck Island Road effluent recharge site on July 26, 2022. This as approach was proposed in the town’s approved multi-phase Comprehensive Wastewater Management Plan (CWMP) and focused on trying to maximize the effluent recharge capacity of that site. Since July, we have had a few conversations with MassDEP hydrogeologic reviewers to try and resolve some of the complex issues at this site. Per MassDEP’s request we have provided additional data, made revisions to the groundwater flow model and simulated additional recharge scenarios. However, the delay in approval of the WP83 Hydrogeologic Evaluation Report application is now preventing the Town from obtaining a Groundwater Discharge Permit (GWDP) for this site. That has resulted in a delay to the Phase 1 Wastewater Program implementation as laid out in the Project Evaluation Form (August 2022) and State Revolving Fund (SRF) application (June 2023). Two collection system contracts totally around $33 Million have been bid and are awaiting Approval to Award (ATA) letters. From our discussions with MassDEP staff, the primary regulatory concern appears to be the MassDEP internal guideline that deals with the intersection of surface water bodies with the extent of the 0.1-foot mound from simulated effluent recharge. This 0.1-foot extent mirrors the MassDEP Drinking Water Program Area of Influence for public water supply source approvals as defined in Section 4.4 of the Guidelines for Public Water Systems1. Based on the above, and in an attempt to move this process forward so that the Town of Yarmouth does not incur several million dollars in increased costs due to delays, we feel it is time to revise the capacity requested in the Hydrogeologic Evaluation Report down to focus on the Phase 1 flows. The Town’s goal is to have MassDEP agree to the smaller flow request and conditionally approve the Hydrogeologic Evaluation Report so that the two currently bid collection system contracts can be 1 Email from Sean Carney (MassDEP) to Karilyn Heisen (CDM Smith) on August 15, 2023. Hydrogeologic Evaluation Application 22-WP83-005-APP – Proposed Pathway Forward September 29, 2023 Page 2 28Sep2023 Proposed Permit Approach.docx awarded and that the Town’s schedule of bidding other Phase 1 contracts is not impacted. To support this approach, we have prepared information for the following three scenarios: Scenario 1 – Maximum Recharge Flow based on 0.1-foot guideline This scenario presents the maximum effluent recharge flow that can be applied at the Buck Island Road site without resulting in a simulated 0.1-foot increase at surface water features. The hydrogeologic steady-state model was run iteratively, with the simulated groundwater recharge reduced until the 0.1-foot groundwater mound contour no longer intersected with a mapped surface water2. This resulted in a recharge rate of 0.29 million gallons per day (MGD)3. The 0.1-foot contour from the 0.29 MGD simulation is shown in Figure 1. Under these conditions, the minimum time of travel from the recharge basins to the Plashes Brook is 74 days4. This steady-state condition equates to 0.37 MGD daily maximum flow, using MassDEP guidance that the simulated value for 0.29 MGD represents 80% of the permissible daily maximum flow. The baseline model simulation represents the 80th percentile high-water conditions documented in the February 22, 2023 memorandum submitted to Mass DEP. The recharge scenario assumes that the cranberry bogs will be used to drain water away from the site, as documented in the February 22, 2023 memorandum. Scenario 2 – Phase 1 Wastewater Flow – Average Annual Conditions The effluent recharge flow in Scenario 1 is significantly lower than the Phase 1 existing flows of 0.417 MGD as presented in the approved CWMP. The hydrogeologic steady-state model was run at a steady-stage flow of 0.417 MGD to determine the mounding impacts. The 0.1-foot contour for the Phase 1 average daily flows of 0.417 MGD is shown on Figure 1. This represents the expected average increase in groundwater elevations from the Phase 1 existing flows. Scenario 3 – Projected Site Capacity Flow CDM Smith revised the groundwater model and completed additional model simulations based on comments and questions from MassDEP. A memorandum documenting these revisions and the revised site capacity was submitted to MassDEP on February 22, 2023. For reference, the 0.1-foot contour from the simulated mounding from a steady-state recharge rate of 0.76 MGD, which equates to a permit rate of 0.95 MGD (0.76 / 80%) is included on Figure 1. This approach is overly conservative with respect to the area of impacted surface waters by simulating the maximum daily flows and not average daily conditions. 2 MassGIS Data: MassDEP Wetlands (2005) dataset, December 2017. https://www.mass.gov/info-details/massgis-data-massdep- wetlands-2005 3 See February 22, 2023 memorandum on Groundwater Model Updates and Revised Site Capacity for the description of the baseline water conditions and use of drainage from cranberry bogs. 4 The time of travel from the proposed discharge to Plashes Brook with 0 additional recharge is around 100 days. Assumed porosity is 0.3. Hydrogeologic Evaluation Application 22-WP83-005-APP – Proposed Pathway Forward September 29, 2023 Page 3 28Sep2023 Proposed Permit Approach.docx Table 1. Summary of simulated scenarios Scenario Average Annual Flow (MGD) Model Simulated Capacity (MGD) Maximum Permitted Flow (MGD) 1. Maximum Recharge Flow based on 0.1-foot guideline a 0.24 0.29 0.37 2. Phase 1 Average Flow 0.417 0.417 b 3. Projected Site Capacity Flow 0.76 0.95 Notes: a – Recharge at site based on area of influence not to exceed 0.1 feet at surface waters. b – Scenario simulated to show impact of average Phase 1 flows. Permitted flow not calculated. Figure 1. Simulated 0.1-foot Groundwater Mound for: Scenario 1 – Maximum Recharge Flow based on 0.1-foot guideline (Dashed contour) Scenario 2 – Phase 1 Average Flow (Red contour) Scenario 3 – Projected Site Capacity Flow (Green contour) Hydrogeologic Evaluation Application 22-WP83-005-APP – Proposed Pathway Forward September 29, 2023 Page 4 28Sep2023 Proposed Permit Approach.docx Scenario 1 and Scenario 2 do not increase water levels below private properties to the east and southeast of the site. The potential increase in water levels in Scenario 3 is small, on the order of 0.1 to 0.2 feet. This increase theoretically could cause groundwater to enter basement structures. Particle tracks show that effluent will either discharge to surface waters or flow at a deeper elevation beneath the properties, so treated effluent would not enter basements. The proposed monitoring plan includes water level observations at MW-23 to quantify the increase in water levels across Plashes Brook due to effluent recharge during the initial phase of the project. The Projected Site Capacity Flow would have minimal impact on water levels beneath the private properties. In addition to the minimal impact, the high-water table occurs in the spring months when effluent recharge rates will be low at the site. Proposed Implementation Schedule and Monitoring Construction of the collection system and water resource recovery facility (WRRF) will take 2 to 3 years and flows will increase gradually after start-up. There is time to collect additional data and evaluate options before flows reach the expected Phase 1 existing flows. • During construction, the Town can monitor pre-recharge conditions to develop a baseline and measure groundwater and surface water interactions. • During initial start-up flows will be low and can serve as pilot study to validate simulated recharge impacts. • This data will provide the base for developing additional mitigation plans, if required, and demonstrate ultimate site capacity. Action Plan The SRF funding window is closing and is critical to Yarmouth’s funding for the Phase 1 program. A proposed Groundwater Discharge Permit capacity request of 0.37 MGD maximum daily flow will allow MassDEP to approve the Hydrogeologic Evaluation Report, allow the town to formally apply for a Groundwater Discharge permit and allow recently bid construction contracts to be awarded. During the construction and initial start-up timeframe, the Town will have ample opportunity to collect data and document baseline conditions, develop operating procedures and allow MassDEP to clarify conflicting guidance so that the ultimate recharge capacity for this site can be determined. Lastly, the Town will need to evaluate other potential recharge options during the initial GWDP period to increase recharge capacity for Phase 1. These options could include: re-evaluate previous effluent recharge site screening analyses, apply for a National Pollutant Discharge Elimination System (NPDES) permit, evaluate increasing treatment and disinfection at the WRRF to apply for an agricultural use reclaimed water permit, look into expanding use of reclaimed water at the Bayberry Hills Golf Course and Bass River Golf Course, and/or consider the environment impacts and cost of a regional ocean outfall. 17Oct2023 Proposed Permit Approach Additional Information.docx Memorandum To: Joe Cerutti, MassDEP From: Karilyn Heisen, CDM Smith Date: October 17, 2023 Subject: Yarmouth MA – Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP – Proposed Permit Approach Additional Information During the October 6, 2023 meeting with the Town of Yarmouth and MassDEP to discuss the 99 Buck Island Road groundwater discharge permit process, you raised a question about why the change in the groundwater mound did not seem to be in proportion to the change in the proposed effluent discharge rates. This memorandum provides additional information including flow budgets. This memo refers to four MODFLOW simulations. The first three simulations were documented in the February 22, 2023 memorandum. The fourth simulation was documented in the September 29, 2023 memorandum. The modeled recharge rate is assumed to represent 80% of the permitted peak discharge permit rate. These simulations are: • High-water conditions – the 80th percentile high water conditions • Drained conditions – assumes the bogs will act as drains and the bogs can be taken off-line as necessary • Proposed Site Flow (0.76 MGD)– assumes the bogs will act as drains, assumes 4-foot separation between bottom of basins and top of groundwater mound, 0.95 MGD permitted rate • Maximum Recharge Flow based on 0.1-foot guideline (0.29 MGD) - 0.37 MGD permitted rate Simulated groundwater elevation contours for each model simulation above are included in the attached figures. The figures include simulated groundwater elevations for the top three active model layers at the site (layers 6, 7 and 8, with 6 being the shallowest active layer). Groundwater elevation contours are shown every 0.5 feet with every 1-foot contour in bold. River and drain boundary conditions are included for each layer. Drain boundaries that are active in each layer are shaded in gray. The orange boxes are the areas used to calculate the surface discharge fluxes included in Table 1. In addition to the groundwater contours, two figures are included for each 22-WP83-005-APP – Proposed Permit Approach Additional Information October 17, 2023 Page 2 17Oct2023 Proposed Permit Approach Additional Information.docx simulation that post the simulated groundwater elevation within each cell near the infiltration basins. The model vertical datum is NGVD29 feet. Since site survey data was recorded using a vertical datum of NAVD88 ft, a correction factor of 0.88 ft should be subtracted from the model elevations to convert from NGVD29 to the site elevations in NAVD88. Specified elevations in the text and figures are in NGVD29 feet for this memorandum. For this site, the mound or “area of influence” is calculated relative to the high water conditions model-simulated water table. The high water level condition used as the basis for calculating the mound is due to a combination of higher recharge from precipitation (35.44 inches per year) and elevated water levels in the bogs. The maximum water level underneath the proposed infiltration basin area is 12.5 ft NGVD29. The simulated conditions with Proposed Site Flow and Maximum Recharge Flow utilize the cranberry bogs to drain away water and lower the water table beneath the infiltration basins. The recharge from rainfall (35.44 inches per year) is unchanged from the high water condition. The bog to the north is assumed to be held at a lower elevation through drainage. The maximum water level underneath the proposed recharge basins in the drained conditions simulation is 10.9 feet NGVD29. Draining the site to this water table elevation requires an increase of 0.67 MGD of flow to drain into the adjacent water bodies. The water levels on-site in the Drained conditions simulation are consistent with the average long- term water levels. Phase 1 of the project will include monitoring of surface water and groundwater levels along with information on the operation of the bog flumes. This data will be utilized to confirm the degree of communication between the surface water and groundwater and the ability of the bogs to drain away water. Monthly surface and groundwater levels were collected as part of the 1985 Facilities Plan. These data suggest that surface water levels in the irrigation pond at the northern end of the bog to the west of the site has an impact on groundwater levels, particularly at monitoring location GW-1. As the water levels show, the groundwater level beneath the recharge basins is simulated to decrease due to the use of the cranberry bogs as drains. The flow budgets for these four scenarios further support the monitoring approach recommended in the Hydrogeologic Evaluation application which includes collection of surface and groundwater data using pressure transducers during initial start-up to better understand the surface and groundwater interactions. The ratio of the flows for the effluent recharge (0.29/0.76 = 0.38) is consistent with the change in water tables [(12.25-10.90)/(13.88-10.90)=0.45] when compared to the drained maximum high water table. 22-WP83-005-APP – Proposed Permit Approach Additional Information October 17, 2023 Page 3 17Oct2023 Proposed Permit Approach Additional Information.docx Table 1. Site zone budget Flow in MGD High Water Conditions Drained Conditions Proposed Site Flow Maximum Recharge based on 0.1- foot guideline Precipitation Recharge 1.47 1.47 1.47 1.47 Effluent Recharge 0 0 0.76 0.29 Groundwater Flux 1.88 2.55 2.49 2.53 Discharge to Surface Water -3.35 -4.02 -4.72 -4.29 Discharge to surface water by Zone Zone 1 (outside of 2, 3, 4) -2.20 -2.81 -3.00 -2.90 Zone 2 -0.76 -0.99 -1.27 -1.11 Zone 3 -0.31 -0.17 -0.34 -0.22 Zone 4 -0.08 -0.05 -0.11 -0.07 Max High Water under beds (ft NGVD29) 12.50 10.90 13.88 12.25 Mounding Relative to the Drained Conditions (feet) N/A 0 2.98 1.35 Attachments: Figure 1-1. High-Water Conditions, Model Layer 6 (20 to 10 feet NGVD29) Figure 1-2. High-Water Conditions, Model Layer 7 (10 to -1 feet NGVD29) Figure 1-3. High-Water Conditions, Model Layer 8 (-1 to -10 feet NGVD29) Figure 1-4. High-Water Conditions, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Figure 1-5. High-Water Conditions, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) Figure 2-1. Drained Conditions, Model Layer 6 (20 to 10 feet NGVD29) Figure 2-2. Drained Conditions, Model Layer 7 (10 to -1 feet NGVD29) Figure 2-3. Drained Conditions, Model Layer 8 (-1 to -10 feet NGVD29) Figure 2-4. Drained Conditions, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Figure 2-5. Drained Conditions, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) Figure 3-1. Proposed Site Flow, Model Layer 6 (20 to 10 feet NGVD29) Figure 3-2. Proposed Site Flow, Model Layer 7 (10 to -1 feet NGVD29) Figure 3-3. Proposed Site Flow, Model Layer 8 (-1 to -10 feet NGVD29) Figure 3-4. Proposed Site Flow, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Figure 3-5. Proposed Site Flow, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) Figure 4-1. Maximum Recharge 0.1-ft Guideline, Model Layer 6 (20 to 10 feet NGVD29) Figure 4-2. Maximum Recharge 0.1-ft Guideline, Model Layer 7 (10 to -1 feet NGVD29) Figure 4-3. Maximum Recharge 0.1-ft Guideline, Model Layer 8 (-1 to -10 feet NGVD29) Figure 4-4. Maximum Recharge 0.1-ft Guideline, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Figure 4-5. Maximum Recharge 0.1-ft Guideline, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) High-Water Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 1-1. High-Water Conditions, Model Layer 6 (20 to 10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 1-2. High-Water Conditions, Model Layer 7 (10 to -1 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 1-3. High-Water Conditions, Model Layer 8 (-1 to -10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 1-4: High-Water Conditions, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 1-5. High-Water Conditions, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) Drained Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 2-1. Drained Conditions, Model Layer 6 (20 to 10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 2-2. Drained Conditions, Model Layer 7 (10 to -1 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 2-3. Drained Conditions, Model Layer 8 (-1 to -10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 2-4. Drained Conditions, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 2-5. Drained Conditions, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) Proposed Site Flow Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 3-1. Proposed Site Flow, Model Layer 6 (20 to 10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 3-2. Proposed Site Flow, Model Layer 7 (10 to -1 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 3-3. Proposed Site Flow, Model Layer 8 (-1 to -10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 3-4. Proposed Site Flow, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 3-5. Proposed Site Flow, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) Maximum Recharge based on 0.1-foot guideline Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 4-1. Maximum Recharge 0.1-ft Guideline, Model Layer 6 (20 to 10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 4-2. Maximum Recharge 0.1-ft Guideline, Model Layer 7 (10 to -1 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Area for Zone Budget Road Infiltration Basin Area MODFLOW river Figure 4-3. Maximum Recharge 0.1-ft Guideline, Model Layer 8 (-1 to -10 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 4-4. Maximum Recharge 0.1-ft Guideline, Simulated Water Levels by Cell, Model Layer 6 (10 to 20 feet NGVD29) Simulated groundwater contours, 0.5 ft interval, 1 ft interval bold Mapped surface water feature MODFLOW drain - Inactive MODFLOW drain - Active Road Infiltration Basin Area 12. 14 Simulated groundwater head Figure 4-5. Maximum Recharge 0.1-ft Guideline, Simulated Water Levels by Cell, Model Layer 7 (10 to -1 feet NGVD29) Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP February 22, 2023 Page 2 21Feb2023 Updated Model and Site Capacity 22-WP83-005-APPdocx.docx Site capacity was calculated using the constant head package (CHD) in MODFLOW. Water levels beneath the proposed recharge area were set to 13 feet (ft) NAVD88, which is 4 ft below the bottom of the infiltration basins. Under high-water table conditions with the cranberry bogs to the north and west assumed to be in operation, the model simulations show 0.53 million gallons per day (MGD) could be recharged under steady-state conditions while maintaining 4 feet separation between the bottom of the infiltration basins and the top of the water table. Per MassDEP guidance, assuming this represents 80% of the peak daily discharge, the permitted site capacity would be 0.66 MGD. If the cranberry bogs were removed from operation, the model simulations show 0.76 MGD could be recharged under steady-state conditions while maintaining 4 feet separation between the bottom of the infiltration basins and the top of the water table. Assuming this represents 80% of the peak daily discharge, the permitted site capacity would be 0.95 MGD. Recharged water would discharge to the cranberry bogs, Plashes Brook, Seine Pond and the Parkers River. The revised model indicates that with 0.76 MGD of recharge, groundwater levels would increase by more than 0.1 ft at the Plashes Brook and wetlands. Figure 11 of this memorandum shows the simulated extent of wetlands and the wetland boundary delineated by CDM Smith wetland scientists in accordance U.S. Army Corps of Engineers 1987 Wetlands Delineation Manual (Environmental Laboratory, 1987), using vegetation, soils and indicators of wetland hydrology. Comparison of the simulated wetland extent and the wetland boundary delineated by the on-site survey shows that the change in the extent of the wetlands is negligible. MassDEP has indicated that an increase of 0.1-ft in groundwater which intersects with a natural waterway (i.e. stream or pond) would be a potential concern. This 0.1-ft condition is not appropriate for the site. The water table on Cape Cod is highly variable and heavily influenced by anthrophonic changes including groundwater withdrawals from pumping, septic system recharge, land use changes, irrigation, and water level control in surface water features. The USGS has studied the impact of pumping on the surface and groundwater in Cape Cod (Walter and Whealan 2005). The study included simulated water table drawdown based on pumping data from 2003 and projected future groundwater withdrawals in 2020. Figure11 from the USGS report, attached to this memorandum, shows that drawdown from pumping near the Buck Island site is around 0.5 feet under 2003 pumping conditions and 1 foot under projected future conditions. Recharge of water at the site would help alleviate decreases in streamflow to Plashes Brook from groundwater supply withdrawals. In addition, based on data available from the Parkers River MEP report (MEP 2010), Plashes Brook is not a natural stream and water level and flow are controlled by releases from the Plashes Pond and the cranberry bog to the north and a water control structure at Winslow Gray Road. Figures 13 and 14 shows the simulated depth to water at high water conditions and with the proposed recharge of 0.76 MGD with the bogs off-line. Comparison between the figures shows that the change in the depth to water beneath structures to the east of Plashes Brook will be very small. Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP February 22, 2023 Page 3 21Feb2023 Updated Model and Site Capacity 22-WP83-005-APPdocx.docx Details on model updates and calibration, discharge capacity simulation including depth to water and expanded wetlands mapping and Plashes Brook flows are detailed below. Attached Figures and Tables Figure 1. Model Boundary Conditions Figure 2. Scatter Plot of Simulated and Observed Water Levels and Table 1. Simulated and Observed Water Levels, Water Level Calibration Statistics and Simulated and Observed Streamflow Figure 3. Simulated Average and High-Water Water Table Contours Figure 4. Simulated Water Table Contours with 0.76 MGD Recharge and Bogs Off-line Figure 5. Simulated Particle Pathlines from 0.76 MGD Recharge the Bogs Off-line Figure 6. West-East and North-South Cross-sections showing Simulated Water Table for Average, High-Water, 0.53 MGD Recharge with Bogs in Operation and 0.76 MGD Recharge the Bogs Off-line Figure 7. Simulated Mounding from Recharge at 0.76 MGD with Bogs Off-line as Compared to Simulated High-Water Figure 8. Simulated Wetland Extent at High Water and Expanded Extent due to Recharge of 0.76 MGD Recharge with Bogs Off-line Figure 9. Simulated Wetland Extent at High Water and Expanded Extent due to Recharge of 0.76 MGD Recharge with Bogs Off-line – Aerial Background Figure 10. Site as Shown on Historic Topographic Maps from 1889 and 1943 Figure 11. Site Survey of Wetlands Compared to Simulated Wetland Extent at High Water and Expanded Extent due to Recharge of 0.76 MGD Recharge with Bogs Off-line Figure 12. Plashes Brook Measured Streamflow (2004-2005) and Daily Precipitation Totals from Barnstable Airport and Table 2. Measured Plashes Brook Streamflow on Days with Greater than 1 inch of Precipitation Photo 1. Plashes Brook Control Structure Looking North from Winslow Gray Road Photo 2. Plashes Brook Looking South from Buck Island Road Photo 3. Water Control Structure in Cranberry Bog to the West of Site January 2010 Figure 13. Simulated Depth to Water (DTW) at High-Water Conditions Figure 14. Simulated Depth to Water at 0.76 MGD Recharge with Bogs Off-line Figure 11 from USGS SIR 2004-5181 Simulated Water Sources and Effects of Pumping on Surface and Ground Water, Sagamore and Monomoy Flow Lenses, Cape Cod, Massachusetts Model Updates and Calibration The site is bounded by multiple surface water features, which impact groundwater flow. These include cranberry bogs to the north and west, Plashes Brook to the east and south and the Parkers River and Seine Pond to the southeast. Based on discussions with Bill Bonnetti, the Director of the Yarmouth Division of Natural Resources, the cranberry bogs to the north and west of 99 Buck Island Road are currently cultivated under a leasing agreement with Quaker Run Cranberries. The bogs are irrigated using water from Plashes Pond or groundwater. During cold periods the bogs are flooded to protect the plants. Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP February 22, 2023 Page 4 21Feb2023 Updated Model and Site Capacity 22-WP83-005-APPdocx.docx Figure 1 shows the location of model boundary cells for the cranberry bogs and wetlands and the assigned elevations for RIV cells in the cranberry bogs. Surface water elevations for the bogs were estimated based on data collected as part of the 1984 Facility Plan. This water level data was provided to MassDEP on December 20, 2022. For model calibration, the water levels were set to 14.12 ft, 13.62 ft and 12.62 ft NAVD88 for the northern bog, the irrigation pond and the western bog respectively. For the high-water period, the water levels were set to 15.12 ft, 15.12 ft and 13.12 ft NAVD88. Conductance for the western bog was modeled as 500 square feet per day (ft2/day) for a 10,000 square foot (ft2) model cell. In addition to the revisions of the cranberry bog and wetland boundaries adjacent to the site, the Parkers River between Long Pond and Seine Pond were also included as drain features. These features were not included in the regional USGS model and has impacts on the water level elevations in the neighborhood to the east of Plashes Brook. The drain elevations for the wetlands adjacent to the site, along Plashes Brook and between Long Pond and Seine Pond were assigned based on LIDAR data. The LIDAR data referenced in this memorandum is the 2011 US Geological Survey Topographic Lidar for the North East. The Lidar data was collected on 1 meter (3.28 ft) ground sampling distance or better and processed to meet a bare earth vertical accuracy of 9.25 centimeters (3.64 inches) root-mean-square-error vertically or better. Drain conductance was set to 300 ft2/day over a 10,000 ft2 model cell for the brook and wetlands along Plashes Brook. The steady-state model was recalibrated to match the observed long-term average water levels. The general recharge from precipitation was 27.26 inches per year with zero recharge on ponds and wetlands, same as the 2011 Hydrogeologic Evaluation model. Hydraulic conductivity values were also unchanged from the 2011 Hydrogeologic Evaluation model. Model boundary conditions were updated as described above. A scatter plot of observed and simulated water levels is shown in Figure 2 and includes both on- site wells and two nearby USGS wells. Model water levels and statistics are presented in Table 1, located beneath Figure 2. Model statistics demonstrate a very good calibration on-site. Compared to the calibration in the 2011 Hydrogeologic Evaluation, the simulated water levels at the northern end of the site better match observed water levels. The model simulated discharge to Plashes Brook north of Winslow Gray Road is 1.22 cubic feet per second (cfs), which is 3.9% less than the average annual observed flow of 1.27 cfs. The updated groundwater model was utilized to develop a new baseline simulation. This simulation represents the 80th percentile groundwater levels, or the “high-water” conditions. Target water levels for the 80th percentile high-water period are from the May 2009 synoptic water level round To simulate the 80th percentile high-water period, model recharge from precipitation was increased by 30% to 35.44 inches per year. For the high-water period, the water levels in the northern and western cranberry bogs were set to 15.12 ft, 15.12 ft and 13.12 ft NAVD88. Simulated streamflow increased by 50% from the simulated average flow of 1.22 cfs to 1.83 cfs. The increase in Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP February 22, 2023 Page 5 21Feb2023 Updated Model and Site Capacity 22-WP83-005-APPdocx.docx streamflow is from both the increase in overall recharge and increased recharge from the higher heads in the cranberry bogs. Observed and simulated water levels for the high-water conditions are shown in the scatterplot in Figure 2 as open symbols. Calibration statistics (residuals) for the high-water simulation are shown Table 1. Groundwater contours of the average simulated steady-state condition and the high-water simulated steady-state condition are shown in Figure 3. Simulated Recharge Capacity Site capacity was calculated using the constant head package (CHD) in MODFLOW. Water levels beneath the proposed recharge area were set to 13 ft NAVD88, which is 4 ft below the bottom of the infiltration basins Under high-water table conditions with the cranberry bogs to the north and west assumed to be in operation, the model simulations show 0.53 MGD could be recharged under steady-state conditions while maintaining 4 feet separation between the bottom of the infiltration basins and the top of the water table. Per MassDEP guidance, assuming this represents 80% of the peak daily discharge, the permitted site capacity would be 0.66 million gallons per day (MGD). The model simulations and observed water levels show that irrigation in the cranberry bogs increases water levels at the site. If the cranberry bogs were removed from operation and used to drain water away from the site, the model simulations show 0.76 MGD could be recharged under high-water steady-state conditions while maintaining 4 feet separation between the bottom of the infiltration basins and the top of the water table. Assuming this represents 80% of the peak daily discharge, the permitted site capacity would be 0.95 MGD. Groundwater contours of the simulated 0.76 MGD recharge during high-water conditions with the bogs off-line is shown in Figure 4. MODPATH was used to simulate particle pathlines from the area of the infiltration basins. The particle pathlines, shown in Figure 5, show the recharged water will discharge to Plashes Brook, the cranberry bog to the west, wetlands to the south and Seine Pond. Cross-sections showing the water table during the average, high-water, recharge of 0.53 MGD with bogs in operation and recharge of 0.76 MGD with bogs off-line is shown in Figure 6. Figure 7 shows the increase in the water table due to the recharge of 0.76 MGD with the bogs off- line. The blue lines on the figure are the mapped extent of existing wetlands as delineated in the MassDEP 2005 wetlands shapefile. The increase or mound is the change in the water table as compared to the high-water simulation. The maximum increase is 3.5 ft beneath the infiltration beds. There is no increase at the cranberry bogs because with the bogs off-line water levels will be lower than in the high-water conditions due to increased drainage through these bogs. The area east of the site around Plashes Brook will have simulated groundwater level increases of over 0.5 ft. Figure 8 shows the extent of the simulated wetlands at high-water (blue) and the additional area (pink) with 0.76 MGD of recharge and the bogs off-line. The wetlands extent was calculated by subtracting the ground surface elevation Lidar data from the model simulated water table. Figure 9 is the same figure with an aerial background for reference. Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP February 22, 2023 Page 6 21Feb2023 Updated Model and Site Capacity 22-WP83-005-APPdocx.docx The revised model indicates that with 0.76 MGD of recharge, groundwater levels would increase by more than 0.1 ft at the Plashes Brook and wetlands. The extent of the wooded wetland area will also expand. MassDEP has indicated that an increase of 0.1-ft in groundwater which intersects with a natural watercourse (i.e. stream or pond) would be a potential concern. Cranberry bogs are natural features and have been harvested for hundreds of years on Cape Cod. Henry Hall of Dennis is credited with the first successful cultivation of cranberries in 1816. Historical records indicate that by 1854, the state’s first census of cranberry land recorded 197 acres in Barnstable County. It is believed that the water control features that exist on Plashes Brook were added to regulate the water level to the bogs once commercial farming was established nearby. For reference, historic topographic maps from 1889 and 1943 are shown in Figure 10. The 1889 map does not show the cranberry bogs existed however that could be attributed to the lack of detail on older topographic or perhaps the bog was modified (cleared, ditches added, etc.) for cranberry farming after 1889. Controlling flow to the bogs resulted in changes to Plashes Pond and Plashes Brook with the construction of water control structures. This indicates that the present day Plashes Brook is also not a naturally flowing waterway. Since the Massachusetts DEP wetlands mapping from 2005 is based on photo-interpretation of wetlands features, it does not include all wetlands, particularly seasonally flooded wetland areas. Figure 11 shows the simulated wetland extent and the wetland extent identified from a on-the- ground wetland delineation survey conducted in 2010 (thick green line). The wetland boundary was delineated by CDM Smith wetland scientists in accordance U.S. Army Corps of Engineers 1987 Wetlands Delineation Manual (Environmental Laboratory, 1987), using vegetation, soils and indicators of wetland hydrology. This shows that the simulated extent of wetlands is similar to the wetlands as field delineated in 2010. The wetlands extent is likely larger than mapped in the 2005 photo interpretation due to low depth to groundwater in these areas and periodic inundation from Plashes Brook. Evidence of the periodic inundation is based on the extent of the wetlands and measured streamflow. Figure 12 shows the Plashes Brook flow reported in the Parkers River MEP report (MEP 2010) and the daily rainfall totals reported at the Hyannis Airport in Barnstable for the period. Table 2, located beneath Figure 12, lists the dates with daily precipitation of greater than 1 inch and the corresponding flow in Plashes Brook. As evidenced by the large spikes in flow on January 23, 2005, upstream releases from the cranberry bogs and Plashes Pond can greatly increase flow, indicating that the brook is a regulated watercourse and not a natural flowing watercourse. For reference, photographs from key features of the site area included. Photo 1 shows the water control structure in Plashes Brook at Winslow Gray Road looking north. The ability to add and remove logs indicates that this control structure can be utilized to control flow in Plashes Brook. Photo 2 shows Plashes Brook looking south from Buck Island Road. The mud along the stream channel shows the variability in water levels. Photo 3 is a picture of the water control structure in Buck Island Hydrogeologic Evaluation Application 22-WP83-005-APP February 22, 2023 Page 7 21Feb2023 Updated Model and Site Capacity 22-WP83-005-APPdocx.docx the cranberry bog to the west of the site. This picture was taken in January 2010 and shows the bog when flooded. Simulated depth to water and the wetlands extent is shown for the high-water conditions in Figure 13 and the 0.76 MGD recharge with bogs off-line in Figure 14. Use of the higher resolution ground surface information and inclusion of the discharge to Parkers River upstream of Seine Pond improved model representations in the neighborhood to the east of the site. Changes in depth to water in this area are minor between the high-water and the recharge scenarios. Elevation Datum Note The model vertical datum is NGVD29 feet. Since site survey data was recorded using a vertical datum of NAVD88 ft, a correction factor of 0.88 ft should be subtracted from the model elevations to convert from NGVD29 to the site elevations in NAVD88 (Milbert 1999). Specified elevations in the text and figures are in NAVD88 unless otherwise specified. References Environmental Laboratory, 1987. “Corps of Engineers Wetlands Delineation Manual“ Technical Report Y-87-1, US Army Engineer Waterways Experiment Station, Vicksburg, Mississippi MEP 2010. Linked Watershed-Embayment Model to Determine Critical Nitrogen Loading Thresholds for the Parkers River Embayment System, Yarmouth, Massachusetts. Final Report – May 2010. University of Massachusetts Dartmouth School of Marine Science and Technology and Massachusetts Department of Environmental Protection. Flow data provided electronically by Roland Samimy on February 12, 2023. NOAA 2011. 2011 U.S. Geological Survey Topographic LiDAR: LiDAR for the North East from 2010- 06-15 to 2010-08-15. NOAA National Centers for Environmental Information, https://www.fisheries.noaa.gov/inport/item/49844. Milbert, D.G., 1999. VertCON 2.0 National Geodetic Survey (NGS) Height Conversion Methodology. Accessed at http://www.ngs.noaa.gov/TOOLS/Vertcon/vertcon.html. Walter, D.A., and Whealan, A.T., 2005. Simulated Water Sources and Effects of Pumping on Surface and Ground Water, Sagamore and Monomoy Flow Lenses, Cape Cod, Massachusetts: U.S. Geological Survey Scientific Investigations Report 2004-5181. Available at https://pubs.usgs.gov/sir/2004/5181/ Wright-Pierce 1984. Facility Plan for Wastewater and Septage Management. Town of Yarmouth, Massachusetts. Prepared by Wright-Pierce, Topsham, Maine, January 1984. Figure 1. Model Boundary ConditionsSeine PondBog to westBog to northPlashes BrookBog ElevationAverage: 12.62High Water: 13.12Pond ElevationAverage: 13.62High Water: 15.12Bog ElevationAverage: 14.12High Water: 15.1222-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 2. Scatter Plot of Simulated and Observed Water LevelsTable 1. Simulated and Observed Water Levels, Water Level Calibration Statistics and Simulated and Observed Streamflow WellLong-term Avg Water Level High Water LevelObs. 2003 to 2010 Simulated ResidualObs. May 2009 Simulated Residualft ft ft ft ft ftMW-22 12.70 12.50 -0.19 13.40 13.42 0.02MW-1 12.20 12.16 -0.03 12.90 13.03 0.13MW-11 11.30 11.16 -0.14 12.50 11.90 -0.60MW-17 9.30 9.05 -0.25 10.30 9.49 -0.81MW-14 9.70 10.03 0.33 10.40 10.62 0.22MW-16 9.30 9.47 0.18 10.00 10.00 0.00IW-1 8.50 8.76 0.26 9.30 9.23 -0.07MW-23 7.20 7.30 0.10 7.30 7.69 0.39MA-YAW89 17.89 15.80 -2.09 19.37 18.58 -0.79MA-YAW94 7.49 10.40 2.91 8.86 11.72 2.86On-site Wells All Wells On-site Wells All WellsAvg 0.03 0.11 -0.09 0.13Abs Avg 0.19 0.65 0.28 0.59St Dev 0.20 1.14 0.38 0.99RMSE 0.21 1.15 0.40 1.00Range 5.50 10.69 6.10 12.07Avg/Range 0.6% 1.0% -1.5% 1.1%AbsAvg/Range 3.4% 6.1% 4.6% 4.9%StDev/Range 3.7% 10.7% 6.3% 8.2%RMSE/Range 3.7% 10.7% 6.5% 8.3%Obs. 2003 to 2010 Simulated Residual Simulatedcfs cfs cfs cfsPlashes Brook 1.27 1.22 -0.05 1.8322-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 3. Simulated Average and High-Water Water Table Contours22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 4. Simulated Water Table Contours with 0.76 MGD Recharge and Bogs Off-line22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 5. Simulated Particle Pathlinesfrom 0.76 MGD Recharge with Bogs Off-line22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 6. West-East and North-South Cross-sections showing Simulated Water Table for Average, High-Water, 0.53 MGD Recharge with Bogs in Operation and 0.76 MGD Recharge the Bogs Off-line 22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 7. Simulated Mounding from Recharge at 0.76 MGD with Bogs Off-line as Compared to Simulated High-Water Conditions0.1 ft0.2 ft0.5 ft1 ftMax 3.5 ft22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 8. Simulated Wetland Extent at High Water and Expanded Extent due to Recharge of 0.76 MGD Recharge with Bogs Off-lineExisting Wetlands22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 9. Simulated Wetland Extent at High Water and Expanded Extent due to Recharge of 0.76 MGD Recharge with Bogs Off-line –Aerial BackgroundExisting Wetlands22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 10. Site as Shown on Historic Topographic Maps from 1889 and 1943Source: USGS Historical Topographic Map Explorer accessed at https://livingatlas.arcgis.com/topoexplorer/index.htmlPlashes Pond water control structure added and increase in pond sizePlashes Brook water control structure added near Winslow Gray RoadNew cranberry bogs1889194322-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 11. Site Survey of Wetlands Compared to Simulated Wetland Extent at High Water and Expanded Extent due to Recharge of 0.76 MGD Recharge with Bogs Off-line22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 12. Plashes Brook Measured Streamflow (2004-2005) and Daily Precipitation Totals from Barnstable Airport Table 2. Measured Plashes Brook Streamflow on Days with Greater than 1 inch of Precipitation 012345678910024681012141618205/1/04 6/1/04 7/1/04 8/1/04 9/1/04 10/1/04 11/1/04 12/1/04 1/1/05 2/1/05 3/1/05 4/1/05 5/1/05 6/1/05 7/1/05 8/1/05 9/1/05 10/1/05 11/1/05 Rainfail Depth (inches) Measured Flow (cfs)DatePrecipitation (inches)Flow (cfs)Date / Time Flow (cfs)Daily Precipitation (inches)9/15/2005 0.41 2.749/29/2004 2.64 2.438/31/2004 2.04 2.071/23/2005 13.68 2.0510/25/2005 1.00 2.024/30/2005 1.53 1.8510/15/2005 2.32 1.643/28/2005 2.31 1.619/16/2005 2.78 1.558/15/2004 0.80 1.483/8/2005 3.58 1.377/8/2005 0.64 1.289/18/2004 0.51 1.285/28/2004 1.92 1.215/7/2005 4.59 1.1710/9/2005 0.49 1.1610/29/2005 0.76 1.0811/13/2004 0.50 1.0222-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Photo 1. Plashes Brook Control Structure Looking North from Winslow Gray Road22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Photo 2. Plashes Brook Looking South from Buck Island Road22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Photo 3. Water Control Structure in Cranberry Bog to the West of Site January 2010 22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 13. Simulated Depth to Water (DTW) at High-Water Conditions22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Figure 14. Simulated Depth to Water at 0.76 MGD Recharge with Bogs Off-lineNote: DTW based on Lidar elevations. DTW will be 4 feet under infiltration beds due to addition of sand up to 17 feet NAVD88. InfiltrationArea22-WP83-005-APP Groundwater Model Updates and Revised Site Capacity – 21 Feb 2023 Walter, D.A., and Whealan, A.T., 2005, Simulated Water Sources and Effects of Pumping on Surface and Ground Water, Sagamore and Monomoy Flow Lenses, Cape Cod, Massachusetts: U.S. Geological Survey Scientific Investigations Report 2004-5181, 85 p.Available at https://pubs.usgs.gov/sir/2004/5181/Buck Island Site