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• Notify Underground Service Alert North (USA North) a minimum of two business days prior to drilling activities to clear public utilities; • Secure the necessary Boring Permit from the SJCEHD. Permit acquisition will involve submitting a completed application and site plan to the SJCEHD for review and approval and remitting the necessary fees.The turnaround time of the SJCEHD to issue the permit is expected to be no more than two weeks; • Notify the applicable regulatory agencies a minimum of 48 hours prior to drilling/backfilling activities; • A geophysical survey will be performed in the vicinity of the former remediation excavation at the subject property to identify its bounds and to additionally clear boring locations of utilities. Boring placement will be modified as necessary based on the geophysical survey results to avoid damaging underground features. Additionally, to the extent practical based on subsurface lithology, clear boring locations using hand tools; • One boring will be advanced with a hollow-stem auger (HSA) in the vicinity of the former remedial excavation (based on data from the geophysical survey and/or historical records) to a terminal depth of 110 feet bgs or groundwater, whichever is shallower, and soil samples will be collected at 5 feet bgs and in 10-foot intervals from 10 feet bgs to the terminal depth and a grab groundwater sample will be collected at the terminal depth; • Ten (10) borings will be advanced with a Geoprobe direct-push rig in the vicinity of the former soil stockpiles and areas of stained soil to a terminal depth of 10 feet bgs, and soil samples will be collected at 2, 5, and 10 feet bgs; • Drilling and sampling equipment will be pre-cleaned prior to arriving on-site. Downhole equipment and materials will be decontaminated in a detergent/tap water and double-rinsed with tap water or with a pressure washer between samples and/or borings to reduce the potential for cross-contamination; • Soil samples advanced by the HSA rig will be collected using 5-foot long, 4.25-inch inner diameter hollow augers with a cutting bit attached to the lead auger, generating loose soil that is lifted to the surface along the exterior auger flights.At the desired sampling depth, a California modified split spoon sampler equipped with three pre-cleaned 6-inch long by 2-inch diameter stainless steel liners will be driven into the soil using a hammer system to allow undisturbed soil to enter the sampler liner at maximum distance of 18 inches or until refusal. The sampler will be retrieved from the subsurface and the soil-filled liners will recovered; • Soil samples advanced by a Geoprobe direct-push rig will be collected using a 4-foot long by 2.25-inch diameter MacroCore sampler with a 4-foot long acetate liner and 4-foot long by 1.5-inch diameter drill rods. The sampler will be driven into the subsurface to allow undisturbed soil to enter the open MacroCore barrel and retrieved in 4-foot intervals to recover the soil-filled liners. • The soil column will be visually inspected for discoloration, monitored for odors, and classified in accordance with the Unified Soil Classification System (USCS). Select intervals were placed in sealable plastic bags and field-screened with a photoionization detector(PID).Soil depths selected for laboratory analysis will be sampled directly from the liners using a disposable plastic syringe and retained in one methanol-preserved and two sodium bisulfate-preserved volatile organics analysis (VOA) vials in accordance with United States Environmental Protection Agency(EPA) Method 5035 sampling protocol. A sample will also be collected by transferring soil into a laboratory-supplied, four-ounce, wide-mouth, unpreserved glass jars, which are sealed with a threaded, Teflon-lined lid.The jars will be filled with soil to capacity to minimize headspace and reduce the potential for volatilization. The jars and VOA vials will be labeled for identification and stored in an iced cooler; • After soil sampling to the terminal depth, a groundwater sample will be collected by withdrawing the augers from the subsurface and installing 3/4-inch diameter temporary monitoring wells within the open borehole.The temporary monitoring well will consist of a 5- or 10-foot long, 0.010-inch factory-slotted Page 3 PARTNER