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other potential obstructions such as a underground tank or buried concrete slabs. Utility Clearance for the boring location will take approximately half an hour to an hour to complete. Environmental Borings One boring (BH-110) will be advanced using direct push technology (DPT) to evaluate subsurface lithology and collect 4-6 soil samples for chemical analysis (total petroleum hydrocarbons [TPH] like gasoline [GRO], diesel [DRO], and oil [MORO]; volatile organic compounds [VOCs] like solvents; polychlorinated biphenyls [PCBs]; and metals). Sample locations were chosen with at least one per acquisition property and analyzed for contaminants of potential concern (COPC) based on nearby or on site potential sources identified in the Phase I investigation and with sites found on GeoTracker. The proposed boring location is approximate and may be moved due to field constraints. At the boring location, concrete or existing pavement will be cored or drilled with the DPT rig, if necessary. With concrete coring, the noise generated will be similar to a table saw and the duration should only last 5 to 10 minutes. With DPT drilling, a hammer drives a steel rod into the ground to create an opening in the pavement. The noise generated can be loud, but typically lasts no longer than 5 minutes. Our field team can provide ear plugs if onsite occupants or tenants are affected. Dust may be generated with either technique but is minimal and does not extend very far from the point of drilling (no more than 2 feet). A hand auger, similar to a post-hole digger, will be used to a minimum depth of 5 feet bgs to clear the location for underground utilities. If samples are to be collected between ground surface and 5 feet bgs, the hand auger will be decontaminated with an Alconox solution between sample collections. Noise and dust generation during the hand auger process is minimal to none, although a rubber mallet or hammer may be used to retrieve the soil from the bucket of the hand auger for soil conditions comprised of silt or clay. The selected drilling contractor will use Geoprobe™ DPT drilling equipment that utilizes a “dual tube” system. A hammer will drive the steel tubes into the ground to collect the soil core. Noise generation will be the same as that experienced during the concrete pavement opening, but dust generation will be minimal to none. Our field team can provide ear plugs if onsite occupants or tenants are affected. The soil core will be contained in an acetate liner used to line the inside of the small diameter casing. A continuous soil core will be collected from the boring and will be logged by an AECOM geologist or engineer in accordance with the Unified Soil Classification System (USCS). Headspace measurements for organic vapors in soil samples will be made in the field using a photo ionization detector (PID). The soil will be placed in a sealable plastic bag, the bag will be sealed, and the soil broken up. The highest PID reading will be recorded for each headspace sample. The used bag and soil will be contained in a DOT-approved drum for disposal at a later date. A detailed field log of the boring will be prepared in the field noting soil type, soil color, groundwater depth, moisture, (density, stiffness, and plasticity as applicable), and PID readings. If high PID readings or visual or olfactory observations indicate the presence of gross contamination at depths, a soil sample will be collected from that interval and submitted for TPH and VOC analysis. If the PID and visual observations don’t indicate a suitable sample location, additional samples may be collected and the maximum number of soil samples for potential chemical analysis to be collected follows the following sample analysis matrix. In general, soil samples will be selected based on the following depths but modified in the field based on PID readings and other visible or olfactory signs of environmental impacts: Soil samples analyzed for VOCs, TPH, metals (including lead), and PCBs will be collected at 1 to 1.5 feet bgs, 4.5 to 5 feet bgs, 9.5 to 10 feet bgs, and 14.5 to 15 feet bgs for the boring. Additionally, soil samples analyzed for lead will be collected from the surface to six inches and 2.5 to 3 feet bgs for the boring. Soil samples collected for VOC and GRO analysis will be collected from the opened acetate liner using a Terra Core® sampler. Soil samples collected for metals, PCBs, and DRO will be collected from the open acetate liner and placed in an 8 oz jar. ATTY/AGR.2025.012/BMR-Bay LP (700, 720, and 740 Bay Road) (Page 13 of 16)