Revised Stormwater Management Report

PA-3 Existing and Proposed 2024-05-12 HydroCad - Proposed 11-12 Multi-Event Tables Prepared by Anderson Consulting Services Printed 6/13/2024 Page 34 HydroCAD® 10.20-5a s/n 06666 © 2023 HydroCAD Software Solutions LLC Events for Subcatchment 26S: Basin 12 pre-dev Event Rainfall (inches) 2-Year 10-Year 100-Year 3.44 5.22 8.66 Runoff (cfs) 0.13 0.30 0.66 Volume Depth (acre-feet) (inches) 0.010 0.023 0.050 1.08 2.37 5.28

PA-3 Existing and Proposed 2024-05-12 HydroCad - Proposed 11-12 Multi-Event Tables Prepared by Anderson Consulting Services Printed 6/13/2024 Page 35 HydroCAD® 10.20-5a s/n 06666 © 2023 HydroCAD Software Solutions LLC Events for Subcatchment 27S: Basin 12 - Imp Event Rainfall (inches) 2-Year 10-Year 100-Year 3.44 5.22 8.66 Runoff (cfs) 0.20 0.30 0.51 Volume Depth (acre-feet) (inches) 0.015 0.024 0.040 3.21 4.98 8.42

PA-3 Existing and Proposed 2024-05-12 HydroCad - Proposed 11-12 Multi-Event Tables Prepared by Anderson Consulting Services Printed 6/13/2024 Page 36 HydroCAD® 10.20-5a s/n 06666 © 2023 HydroCAD Software Solutions LLC Events for Subcatchment 29S: Basin 12 - Perv Event Rainfall (inches) 2-Year 10-Year 100-Year 3.44 5.22 8.66 Runoff (cfs) 0.18 0.39 0.83 Volume Depth (acre-feet) (inches) 0.012 0.026 0.055 1.20 2.54 5.52

PA-3 Existing and Proposed 2024-05-12 HydroCad - Proposed 11-12 Multi-Event Tables Prepared by Anderson Consulting Services Printed 6/13/2024 Page 37 HydroCAD® 10.20-5a s/n 06666 © 2023 HydroCAD Software Solutions LLC Events for Pond 30: Basin 12 Event Inflow (cfs) Discarded (cfs) Elevation (feet) Storage (cubic-feet) 2-Year 10-Year 100-Year 0.38 0.69 1.33 0.08 0.08 0.08 594.60 595.65 598.42 215 595 1,652

Cy # f Input Values R Recharge rate (permeability rate) (in/hr) Specific yield, Sy (dimensionless) sy default value is 0.15; max value is 0.2 provided that a lab test data Is submitted Horizontal hydraulic conductivity (in/hr) Kh Kh = 5xRecharge Rate (R) in the costal plan; Kh=R outside the coastal plan x 1/2 length of basin (x direction, in feet) y 1/2 width of basin (y direction, in feet) t Duration of infiltration period (hours) hi(o) Initial thickness of saturated zone (feet) Ti] —h(max) Maximum thickness of saturated zone (beneath center of basin at end of infiltration period) Tz] ahtman) Maximum groundwater mounding (beneath center of basin at end of infiltration period) Distance from Ground-water _center of basin inx Mounding, in feet direction, in feet [Pipe cateuete Now oo a ~ ~ — = 1 a = 3 < 5 a = 5 a ic} 2 = ra) < 3 EF Fj a 5 | = @ o a oo 110 120 130 140 150 Disclaimer This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins" or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet (other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences. These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet, the user is responsible for documenting the changes and justifying the results and conclusions.

ge Input Values R Recharge rate (permeability rate) (in/hr) Specific yield, Sy (dimensionless) sy default value is 0.15; max value is 0.2 provided that a lab test data is submitted Horizontal hydraulic conductivity (in/hr) Kh Kh = 5xRecharge Rate (R) in the costal plan; Kh=R outside the coastal plan x 1/2 length of basin (x direction, in feet) y 1/2 width of basin (y direction, in feet) t Duration of infiltration period (hours) hilo) Initial thickness of saturated zone (feet) ivi h{max) Maximum thickness of saturated zone (beneath center of basin at end of infiltration period) ee] Ah(max) Maximum groundwater mounding (beneath center of basin at end of infiltration period) Distance from Ground-water center of basin in x. Mounding, in feet direction, in feet Re-Calculate Now Groundwater Mounding, in feet 2.000 1.500 0,001 1.000 0.500 0.000 ' 120 130 140 150 -0.500 a 7 oo eee -_ Disclaimer This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins" or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet (other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences. These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet, the user is responsible for documenting the changes and justifying the results and conclusions.

Input Values R Recharge rate (permeability rate) (in/hr) Specific yield, Sy (dimensionless) sy default value is 0.15; max value is 0.2 provided that a lab test data is submitted Horizontal hydraulic conductivity (in/hr) Kh Kh = SxRecharge Rate (R) in the costal plan; Kh=R outside the coastal plan x 1/2 length of basin (x direction, in feet) y 1/2 width of basin (y direction, in feet) t Duration of infiltration period (hours) Ai(a) Initial thickness of saturated zone (feet) h{max) Maximum thickness of saturated zone (beneath center of basin at end of infiltration period) 0778 Mes) Maximum groundwater mounding (beneath center of basin at end of infiltration period) Distance from Ground-water —_center of basin inx Mounding, in feet_direction, in feet Re-Calculate Now Groundwater Mounding, in feet | 0.900 0,000 2 0.800 0.000 0.000 0.000 0.000 0.700 0.600 0.500 0.300 0.200 +: 0.100 0.000 | | | | | i | | ooo | | | er 100110 120 130 140 150 Disclaimer This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins" or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet (other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences. These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet, the user is responsible for documenting the changes and justifying the results and conclusions.

Input Values hi(o) (max) Ah(max) Distance from Ground-water _ center of basin in x. Mounding, in feet direction, in feet 0,001 Disclaimer 4 Recharge rate (permeability rate) (in/hr) Specific yield, Sy (dimensionless) default value 's 0.15; max value is 0.2 provided that a lab test data is submitted Horizontal hydraulic conductivity (in/hr) Kh = 5xRecharge Rate (R) in the costal plan; Kh=R outside the coastal plan 1/2 length of basin (x direction, in feet) 1/2 width of basin (y direction, in feet) Duration of infiltration period (hours) Initial thickness of saturated zone (feet) Maximum thickness of saturated zone (beneath center of basin at end of infiltration period) Maximum groundwater mounding (beneath center of basin at end of infiltration period) Re-Calculate Now Groundwater Mounding, in feet 3,000 2.500 100 110 120 130 140 150 This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins" or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet (other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences. These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet, the user is responsible for documenting the changes and justifying the results and conclusions.

Input Values R Recharge rate (permeability rate) (in/hr) Specific yield, Sy (dimensionless) sy default value is 0.15; max value is 0.2 provided that a lab test data is submitted Horizontal hydraulic conductivity (in/hr) Kh Kh = SxRecharge Rate (R) in the costal plan; Kh=R outside the coastal plan x 1/2 length of basin (x direction, in feet) y 1/2 width of basin (y direction, in feet) t Duration of infiltration period (hours) hi(o) Initial thickness of saturated zone (feet) 10.667 (max) Maximum thickness of saturated zone (beneath center of basin at end of infiltration period) 0.667 Ah(max) Maximum groundwater mounding (beneath center of basin at end of infiltration period) Distance from Ground-water center of basin inx Mounding, in feet_direction, in feet Re-Calculate Now Groundwater Mounding, in feet 0,000 0,000 0.000 0.000 0.000 90 100 110 120 130 140 150 Disclaimer This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins" or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet (other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences. These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet, the user is responsible for documenting the changes and justifying the results and conclusions.

Input Values R Recharge rate (permeability rate) (in/hr) Specific yield, Sy (dimensionless) sy default value is 0.15; max value is 0.2 provided that a lab test data is submitted Horizontal hydraulic conductivity (in/hr) Kh Kh = 5xRecharge Rate (R) in the costal plan; kh=R outside the coastal plan x 1/2 length of basin (x direction, in feet) y 1/2 width of basin (y direction, in feet) t Duration of infiltration period (hours) hi(o) Initial thickness of saturated zone (feet) h{max) Maximum thickness of saturated zone (beneath center of basin at end of infiltration period) Ah{max) Maximum groundwater mounding (beneath center of basin at end of infiltration period) Distance from center of basin in x Mounding, in feet_direction, in feet Ground-water 0.000 0.000 0,000 Disclaimer Re-Calculate Now Groundwater Mounding, in feet KY 100 110 120 130 140 150 This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltration basin is made available to the general public as a convenience for those wishing to replicate values documented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneath hypothetical stormwater infiltration basins” or to calculate values based on user-specified site conditions. Any changes made to the spreadsheet (other than values identified as user-specified) after transmission from the USGS could have unintended, undesirable consequences. These consequences could include, but may not be limited to: erroneous output, numerical instabilities, and violations of underlying assumptions that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the spreadsheet. If changes are made to the spreadsheet, the user is responsible for documenting the changes and justifying the results and conclusions.