Response Letter 3226rcd 3 12 2026

10. 11. 12 13. 14, 15. 16. 17. Revise the plans to ensure that all inlet grates are set higher than the 100-year water surface elevation within the basins. This comment has been addressed, and all inlet grates have been set to be higher than the 100-year water surface elevation of 412.33 feet. The proposed inlet located at the bottom of the proposed staircase provides 6" of cover over the top of the pipe. The concrete sidewalk detail on sheet 8 indicates that 4" of concrete and 4" of stone is required for concrete sidewalk installation. Therefore, it appears that additional cover should be provided over the pipe. This comment has been addressed, and the plan has been revised to indicate 1.5’ of cover over the top of the pipe coming out of the inlet at the bottom of staircase. . The design of the proposed underground basin should be clarified. The basin is indicated on the Grading, Drainage, Soil Erosion & Sediment Control Plan (sheet 6) as a detention basin, however, it will be constructed with perforated pipes (infiltration) and is modeled with exfiltration within the hydrograph routings. Our office notes that underground detention basins are only permitted when granted a waiver or variance from NJAC 7:8-5.3. This comment has been addressed, and the underground pipe system has been renamed to an infiltration system Groundwater mounding and duration of infiltration period calculations should be provided for all proposed infiltration systems. This comment has been addressed, and groundwater mounding calculations have been provided for both the pipes and the paver systems. Revise the plans to clarify how roof runoff will be pre-treated prior to infiltration. This comment does not need to be addressed as it is not required to pre-treat roof runoff. Revise the permeable pavement detail on the Construction Details (sheet 8) to indicate the separation from the bottom of the system to the seasonal high water table elevation. Additionally, the detail should be revised to indicate that filter fabric should be installed on the sides of the storage bed. This comment has been addressed, and the pervious paver detail has been revised to show a distance to the SHWT and the filter fabrics needed. Revise the Grading, Drainage, Soil Erosion & Sediment Control Plan (sheet 6) to provide at least one inspection port within the permeable pavement

distance to the SHWT and the filter fabrics needed. Revise the Grading, Drainage, Soil Erosion & Sediment Control Plan (sheet 6) to provide at least one inspection port within the permeable pavement system. Further, the permeable pavement detail should be revised accordingly. This comment has been addressed, and the pervious paver detail has been revised to display the inspection port. Pipe capacity calculations should be provided for review. This comment has been addressed, and pipe capacity calculations have been added to the Stormwater Management Report.