24 07 24 Review 1 CME

"ses ASSOCIATES, Chairman and Members of the West Orange Township Zoning Board July 24, 2024 Re: PSE&G Company (ZB-24-06) Our File No. 115.WRZ0155.V04 Preliminary & Final Site Plan with ‘C’ and ‘D' Page 6 Variances and Tree Removal Permit - Review #1 C. DRAINAGE COMMENTS 1. The proposed development will result in the disturbance of more than one acre. As a result, it is classified as a Major Development which requires that the project be designed to meet the stormwater runoff quality, quantity and groundwater recharge standards using green infrastructure. We note that trench drains are proposed adjacent to each bioretention basin to prevent off-site drainage from entering the bioretention basins. The flows from the trench drains will connect to a separate stormwater conveyance system which will discharge to the existing stormwater system in Mt. Pleasant Avenue. The areas that will discharge to the trench drains are not proposed for development and will remain in their existing condition. The Bioretention and Control Structure Elevations and Control Orifices table on sheet 792798 should be revised to label the Top of Basin Wall Elevation as E to match the Typical Concrete Lined Small-Scale Bioretention with Underdrain Detail on the same sheet. The Bioretention Media Notes on sheet 792798 should be revised to include a note which states “The soil bed material must be placed in lifts not to exceed 6 inches”. The plans should be revised to provide maintenance access to each proposed basin. It shows on the Bioretention and Control Structure Elevations and Control Orifices table , that each basin will have a freeboard of only 0.1 feet between the top of wall and the top of overflow grate. It is our recommendation that a minimum freeboard of 1.0 ft be provided. It shows on the Conduit Table in the Stormwater Report that the following pipe runs do not have adequate capacity to accommodate the design flow: a) SD-01 b) SD-02 c) SD-04 d) SD-12 e) SD-21 f) SD-22 g) SD-23 h) SD-24 i) SD-25 The Small Scale Bioretention Outlet Structure detail on sheet 792798 shows a 2.5” water quality control orifice with a trash rack at Elevation G. It is our understanding that the 4” perforated underdrain pipe will connect to the outlet structure at this location. Therefore, the trash rack is not required at this location and should be deleted. ‘§:\West Orenge\Zoning

that the 4” perforated underdrain pipe will connect to the outlet structure at this location. Therefore, the trash rack is not required at this location and should be deleted. ‘§:\West Orenge\Zoning Board\ 15. WRZ0155.VO4 - PSE&G Company\24-07-24 Review #1,docx