Stormwater Management Report 03302026

1500 B-3 4—6 30 FILL +5000 4000 B-3 6—8 19 SP-SM 3800 4000 B-3 8 — 9'-2" 44/2 SP/GP +5000 5000 B-3 @ 9'-5" Augur Refusal - +5000 8000 In-Place Penetration Recommended Boring Depth in Soil Soil Bearing Resistance Soil Bearing Number (feet) Type N-Value Capacity (PSF) C(PSF)~ B-4 0—2 9 FILL 1800 1000

Client: Gomes Management Project: 525 Northfield Avenue, West Orange, NJ Page: 5 Date: 09/03/2024 B-4 2—4 15 SM/GM 3000 2500 B-4 4 — 5'-2" 45/2 GM-SM +5000 4500 B-4 6- 8 62 SM/GM +5000 5000 B-4 8 - 10 94 SM/GM +5000 5000 B-4 10 - 10'-10" 52/4 SP/GP +5000 5000 B-4 @11'-2" Augur Refusal - +5000 8000 In-Place Penetration Recommended Boring Depth in Soil Soil Bearing Resistance Soil Bearing Number (feet) Type C~PSFjty N-Value Capacity (PSF) B-5/5A 0 - 1'-8" 26 FILL +5000 1500 B-5/5A 2- 4 6 FILL 1200 1500 B-5/5A 4- 6 15 SM/GM 3000 3000 B-5/5A 6- 8 19 SM/GM 3800 4000 B-5/5A 8 - 10 55 SM/GM +5000 5000 B-5/5A 10 - 11'-1" 93/7 SM/GM +5000 5000 B-5/5A 15 - 15'-3" 78/3 SM/GM +5000 5000 B-5/5A @19'-9" Augur Refusal - +5000 8000 In-Place Penetration Recommended Boring Depth in Soil Soil Bearing Resistance

Recommended Boring Depth in Soil Soil Bearing Resistance Soil Bearing Number (feet) Type C(PSFjty N-Value Capacity (PSF) B-6 0- 2 21 SP-SM 4200 1500 B-6 2- 4 8 SM/GM 1600 1500 B-6 4- 6 6 SM/GM 1200 1500 B-6 6- 8 5 SM/GM 1000 1000 - B-6 - 8 - 10 - - 13 - SM/GM 2600 2500 B-6 10 - 12 28 SM/GM +5000 5000 B-6 15 - 17 52 SM/GM +5000 5000 B-6 20 - 22 47 SM/GM +5000 5000 B-6 25 - 25'-7" 50/1 SM/GM +5000 6000 In-Place Penetration Recommended Boring Depth in Soil Soil Bearing Resistance Soil Bearing Number (feet) Type C~PSFjty N-Value Capacity (PSF) B-7 0- 2 16 SM/GM 3200 3000 B-7 2- 4 17 SM/GM 3400 3500 B-7 4- 6 23 SM/GM 4600 4000 B-7 6- 8 7 SM/GM 1400 1500 B-7 8 - 10 10 SM/GM 2000 2000 B-7 10 - 12 18

SM/GM 1400 1500 B-7 8 - 10 10 SM/GM 2000 2000 B-7 10 - 12 18 SM/GM 3600 4000 B-7 @14'-2" Augur Refusal - +5000 8000 In-Place Penetration Recommended Boring Depth in Soil Soil Bearing Resistance Soil Bearing Number (feet) Type C(PS~jty N-Value Capacity (PSF) B-8 0- 2 15 FILL 3000 1500 B-8 2- 4 25 SM/GM 5000 1500 B-8 4- 6 5 SM/GM 1000 1000 B-8 6 - 7'-9" 5 SM/GM 1000 1000 B-8 9 - 11 6 SM/GM 1200 1500 B-8 11 - 13 19 SP/GP 3800 3500 B-8 15 - 17 44 SM/GM +5000 4500 B-8 @19'-2" Augur Refusal - +5000 6000

Client: Gomes Management Project: 525 Northfield Avenue, West Orange, NJ Page: 6 Date: 09/03/2024 GROUNDWATER: Groundwater was encountered in only two borings B-6 & B-8 below existing grade surface as follows: Depth to Depth to Boring Boring Groundwater Groundwater Number Number (feet) (feet) B-1 - B-5 Hole collapsed at 9'-2" B-2 Hole collapsed at 7'-5" B-6 11'-1" B-3 Hole collapsed at 7'-2" B-7 - B-4 Hole collapsed at 4'-4" B-8 8'-9" It should be noted that groundwater level will fluctuate due to variations in rainfall or other factors not evident at the time of our investigation. SEASONAL HIGH WATER TABLE: Signs of black mottling was noted at 6 feet depth in only boring B-7, indicating SHWT below 6 feet. CONCLUSIONS: 1. Groundwater was encountered at 11'- 1" in B-6 and at 8'- 9" in B-8 below existing grade surface. Consequently, we anticipate that groundwater management during construction will be critical. 2. Signs of black mottling was noted at 6 feet depth in only boring B-7, indicating SHWT below 6 feet. 3. Fill was noted in top 2'-6" in boring B-1, in top 4' in B-2/2A, in top 4'-11" in B-3, in top 5" in B-4, in top 2' in B-5/5A and in top 9" in B-8. Below fill, the majority of the on-site soil consists of silt with trace f/c sand &trace f/m gravel. The onsite soil will be suitable as structural fill. Depending upon the time of the year when the actual construction takes place, drying of excavated sandy soil and aeration may be required to reduce the moisture content. In-situ moisture content of soil varied between 5.5 % to 14.2 %which is

ction takes place, drying of excavated sandy soil and aeration may be required to reduce the moisture content. In-situ moisture content of soil varied between 5.5 % to 14.2 %which is generally considered moist. 4. The following parameters should be used for seismic design of the building in accordance with IBC-2021 ASCE 7-22: Description Parameter Recommended value Mapped Spectral Acceleration for short periods: Ss 0.27 Mapped Spectral Acceleration for 1-sec period: S, 0.05 Site Class: C Very dense Soil &Soft Rock 5 percent damped Design spectral response Sos 0.18 acceleration at short periods: 5 percent damped Design spectral response So, 0.043 acceleration at 1-sec periods: The following parameters should be used for seismic design of the building in accordance with IBC-2018-ASCE 7-16:

Client: Gomes Management Project: 525 Northfield Avenue, West Orange, NJ Page: 7 Date: 09/03/2024 Description Parameter Recommended Value Mapped Spectral Acceleration for short periods: Ss 0.282 Mapped Spectral Acceleration for 1-sec period: S, 0.059 Site Class: C Very dense Soil &Soft Rock Site Coefficient: Fa 1.3 Site Coefficient: Fv 1.5 5 percent damped Design spectral response Sos 0.245 acceleration at short periods: 5 percent damped Design spectral response So, 0.059 acceleration at 1-sec periods: 5. Any fill used as backfill material within the building and pavement areas should consist of approved portions of the on-site granular soils, which have been maintained at moisture contents suitable for compaction or select fill should be imported. All fill should be placed in lift in the order of twelve (12) inches in loose thickness and be uniformly compacted to at least 95% of its maximum dry density as determined by the modified proctor density values derived based upon ASTM D-1557-98 test procedure. In addition, we recommend that backfill soil placed in confined areas, such as foundation or utility excavations, should be spread in lifts in the order of six (6) to eight (8) inches in loose thickens and it should be compacted to the same degree using manually operated vibratory compaction equipment. We recommend that temporary construction slopes be established atone vertical to two horizontal, or flatter, or as required by the governing safety codes. FOUNDATION DESIGN CRITERIA: As per the r2-coastal-fema.hub.arcgis.com website and FIRM-(flood insurance rate map), the Effective Flood Zone of the subject property is AE. The properties in these flood zones

As per the r2-coastal-fema.hub.arcgis.com website and FIRM-(flood insurance rate map), the Effective Flood Zone of the subject property is AE. The properties in these flood zones have a 1%chance of flooding each year. Fill was noted in top 2'-6" in boring B-1, in top 4' in B-2/2A, in top 4'-11" in B-3, in top 5" in B-4, in top 2' in B-5/5A and in top 9" in B-8. We recommend that the foundation for the proposed 1-story retail building shall be supported by conventional shallow foundations established on the medium dense soil noted at 4' to 6' depth below grade. Foundation should be designed to impose maximum allowable net bearing pressure of 2,000 pounds per square foot. Excavation down to 10 feet depth will be required in borings B-6, B-7 & B-8 to get net bearing pressure of 4,000 psf. A complete removal of fill is recommended. Any pockets of localized unsuitable soil encountered during foundation excavation should be completely removed. The over excavated area should be backfilled utilizing either controlled compacted fill or 3/4" size clean gravels. Any footing or slab placed in this area will require over excavation, removal of unsuitable material and backfilling with 3/ 4 size stones or controlled compacted fill. Placing additional reinforcing steel to strength the footing over soft soil may be required. We recommend that exterior foundations be established at least three feet six inches below the adjacent exterior grade, or as required by local ordinance, to provide protection from frost penetration. The maximum post-construction settlements of foundations designed and constructed in accordance with our recommendations will be in the order of 3/ " or less.

Client: Gomes Management Project: 525 Northfield Avenue, West Orange, NJ Page: 8 Date: 09/03/2024 FLOOR SLAB DESIGN CRITERIA: Removal of fill from top 2'-6" in boring B-1, from top 4' in B-2/2A, from top 4'-11" in B- 3, from top 5" in B-4, from top 2' in B-5/5A and from top 9" in B-8 will be required. The floor slab or patio slab shall be supported directly on the compacted sub-grade of onsite material or controlled compacted structural fill. Compaction of the sand below the floor slab sub-grade to 95% of its optimum density will be required. We recommend performing compaction test at the rate of one test per 200-sq.ft area. Recommended Modulus of Sub-Grade reaction is 75 pci. Any back fill required for the structural area to be off site or 3/ 4" clean crushed stones may be utilized to minimize the influence of moisture on the first fill layer. All off-site fill should composed of relatively well graded sand and gravel containing less than 15% by weight passing U.S. Standard #200 sieve and having a maximum particle size of six inches. Acceptable soil materials for backfill and fill should be free of clay, rock or gravel larger than six (6) inches in any dimension, debris, waste, frozen materials, vegetable and other deleterious matter and it should comply with ASTM D-2487-91 soil classification groups GW, GP, SM, SW and SP. All fill should be placed in lifts in the order of twelve (12) inches in loose thickness and it should be uniformly compacted to at least 95% of its maximum dry density as determined by the modified proctor density values derived based upon ASTM D-1557-93 test procedure. In addition, we recommend that backfill soils placed in confined areas, such as foundation or utility excavations, should be spread in lifts in the order of six to eight inches in loose thickness and be compacted to the same degree using manually operated vibratory compaction equipment. BELOW GRADE WALLS: We recommend that the exterior building walls should be constructed with a continuous perimeter foundation drain to convey localized groundwater seepage away from the building and prevent the hydrostatic pressures built-up against

s should be constructed with a continuous perimeter foundation drain to convey localized groundwater seepage away from the building and prevent the hydrostatic pressures built-up against the walls. The drain could consist of a 6 to 8 inch diameter PVC pipe surrounded on all sides by a minimum of six (6) inches of clean 3/8" crushed gravel. The pipe should drain by gravity to the site storm water system, if feasible, or should be connected to a sump pit where any water could be removed by pumping. Soil Unit weight (total): 120 pcf Angle of Internal Friction: 31 degrees Coefficient of sliding friction: 0.4 Coefficient of active earth pressure: 0.28 Coefficient of passive earth pressure: 3.57 RECOMMENDATIONS FOR THE EARTHWORK FOUNDATION CONSTRUCTION: Clearing and Stripping: Clearing and stripping would include removing vegetation and any boulders or any loose or unsuitable soil at the distance of 5 feet beyond the limits of the proposed building excavation, structure and paved areas. Limits of stripping should conform to construction permit limitations. Soil Erosion and Sediment Control: Clearing and stripping should be performed in accordance with the requirements of the soil erosion and sediment control plan and environment permits.