CME Associates Review 1

NO CMe ASSOCIATES Chairman and Members of the West Orange Township Planning Board June 26, 2024 Re: West Essex Highlands, LLC (PB 24-01) Our File No. VWRP0179.01 Preliminary & Final Site Plan - Review #1 Page 9 55. The plans should be revised to include details of the following improvements that are proposed: a) Keep Right Around Circle sign. b) Electric Vehicle parking space sign. c) Pump stations. d) Emergency access drive to Howell Drive. e) Emergency access drive gate. f) Retaining walls. g) Drainage inlets h) Drainage headwalls. i) Porous HDPE pipe installation detail. J) _ Inflow level spreaders. k) Storm manhole. !) Sanitary sewer manhole. m) Sanitary force main. E. 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 and is subject to the stormwater management requirements set forth in Section 25-29.4 of the Ordinance. 2. In accordance with Section 25-29.4.h, whenever the stormwater management design includes one or more BMPs that will infiltrate stormwater into subsoil, the design engineer shall assess the hydraulic impact on the groundwater table and design the site so as to avoid adverse hydraulic impacts. A groundwater mounding analysis for all BMPs designed to infiltrate into the subsoil shall be provided. 3. In accordance with Section 25-29.4.j, manufactured treatment devices may be used to meet the requirements of this subchapter, provided the pollutant removal rates verified by the New Jersey Corporation for Advanced Technology and certified by NJDEP. The Applicant should provide copies of the NJDEP certification to confirm the proposed MTD’s will meet the green infrastructure requirements. 4. In accordance with Section 25-29.5.a.4, in computing stormwater runoff from all design storms, the design engineer shall consider the relative stormwater runoff rates and/or volumes of pervious and impervious surfaces separately to accurately compute the rates and volume stormwater runoff from the site. The SWM report should be revised to comply with same. 5. In accordance with Chapter 5 of the New Jersey Stormwater Best Management Practices (BMP) Manual, a minimum or default value may not be used for time of concentration. We note that a minimum Tc of 10 min is used for several hydrographs. Time of concentration for pre- and

nt Practices (BMP) Manual, a minimum or default value may not be used for time of concentration. We note that a minimum Tc of 10 min is used for several hydrographs. Time of concentration for pre- and post-development conditions must be calculated and used in the stormwater analysis. The SWM report shall be revised to comply with same. ‘S:\West Orange\Planning Board\VWRPO179.01 - West Essex Highlands, Inc\Review #1 06-26-24 docx