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West Essex Highlands Review West Orange, NJ Permit No. 722-04-0001.1 LUP230001 April 2025 ¢ Peak flow calculations « Impacts to onsite wetlands 1.0 INTRODUCTION West Essex Highlands is a proposed multi-family residential development with recreational facilities and a clubhouse with a limit of disturbance of 1,233,793 sf (28.35 acres). The 120.4 acre parcel is located in the headwaters of Canoe Brook and is currently undeveloped. The steeply sloping site is almost completely forested. The West Essex Highlands development project is currently being reviewed by the Township of West Orange Municipal for Planning Board approval and the proposed project will necessitate the removal of approximately 28.35 acres of relatively mature forest. The purpose of this letter is to briefly summarize the various deficiencies identified during our review of the revised application materials related to critical aspects of the application's compliance with the New Jersey Stormwater Management Rules at N.J.A.C. 7:8, the BMP Manual and the Township's local stormwater ordinance, § 25-29 of the general ordinances. 2.0 STORMWATER MANAGEMENT It is our professional opinion that the applicant failed to demonstrate compliance with the requirements of N.J.A.C. 7:8.The site plans and stormwater calculations have been reviewed to determine if the design engineer, Anderson Consulting Services LLC (ACS), has demonstrated compliance with N.J.A.C. 7:8, the New Jersey BMP Manual and §25-29 of the Township of West Orange's local stormwater ordinance. We find that both the application to the Township as well as the information submitted to the NJDEP fail to demonstrate that the soil testing requirements of Chapter 12 of the New Jersey BMP Manual have been satisfied for two of the three primary stormwater management performance metrics, groundwater recharge (section P of §25-29) and stormwater runoff quantity standards (section R of §25-29). The following subsections outline our specific concerns as they relate to these three areas with the application submission. 2.1 SOIL TESTING REQUIREMENTS Before discussing the issues of compliance with two of the three primary stormwater management performance metrics, this section will discuss the soil testing requirements as set forth in Chapter 12 of the New Jersey BMP Manual and compare it to the soil testing documentation provided in this

t performance metrics, this section will discuss the soil testing requirements as set forth in Chapter 12 of the New Jersey BMP Manual and compare it to the soil testing documentation provided in this application. The New Jersey BMP manual was developed to provide examples of ways to meet stormwater design standards set by the state. The New Jersey BMP Manual was developed by the NJDEP, in coordination with the New Jersey Department of Agriculture, the New Jersey Department of Community Affairs, the New Jersey Department of Transportation, municipal engineers, county engineers, consulting firms, contractors, and environmental organizations. As stated in Chapter 12 of the New Jersey BMP Manual, understanding the character and saturated hydraulic conductivity of surface and subsurface soils at a proposed land development site is crucial to the design of stormwater best management practices (BMPs) that meet the requirements of the New Jersey Stormwater Management rules at N.J.A.C. 7:8 and §25-29 of the local ordinance. Section 2 of Chapter 12 further clarifies that saturated hydraulic conductivity and depth to SeasonalHigh Water Table (SHWT) are of high importance for the design of stormwater BMPs. Subsection 1d of Chapter 12 Princeton Hydro, LLC Page | 3