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• Notify the applicable regulatory agencies a minimum of 48 hours prior to drilling/backfilling activities; • Clear boreholes/probes of utility lines through a geophysical survey. 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; • Complete a site checklist to identify substances within the areas to be tested that may contribute to any constituents identified in indoor/outdoor air samples. Partner will perform visual inspections and conduct interviews with on-site personal to document any factors that may influence indoor/outdoor air quality. To minimize potential impacts on the air samples, air sample locations will be strategically selected to avoid areas with potential interior contaminant sources; • Photograph site conditions; • Collect a total of five air samples using laboratory-provided, individually-certified clean 3- or 6-liter SUMMA canisters. Two samples will be collected from the interior of Suite 308A (former on-site dry cleaning facility suite), one sample will be collected from the interior of Suite 306, one sample will be collected from the interior of Suite 308B, and one ambient sample will be collected to the exterior of the building. Air sampling activities will be conducted during normal business hours/operations, with the building heating,ventilation, and air conditioning (HVAC) system on; • In general, indoor air samples will collected away from entrances and in areas where the air is relatively still to minimize potential dilution effects from outside air.Also,the indoor and outdoor air samples will be placed in strategic areas to avoid any disturbance from on-site employees and the public; • Partner will periodically monitor the sampling equipment; • Provide flow controllers for each canister calibrated to collect samples over an 8-hour period; • Analyze the two air samples collected from Suite 308A and the ambient air sample for CVOCs [specifically PCE; trichloroethene (TCE); 1,1-dichloroethene (DCE); cis-1,2-DCE;trans-1,2-DCE; and vinyl chloride) via EPA Method TO-15 Selective Ion Monitoring (SIM) Method (ultra-trace detection limit); and • Hold the two air samples collected from Suite 306 and 308B at the laboratory for potential future analysis based on the results of the additional soil gas sampling; • Advance two borings in Suite 308A to a terminal depth of 15 feet bgs collecting soil samples at 2 feet bgs and in 5-foot intervals from 5 feet bgs to the terminal depth; • Advance two borings on the exterior of the building to a terminal depth of 50 feet bgs or groundwater, whichever is shallower, collecting soil samples at 2 feet bgs and in 5-foot intervals from 5 feet bgs to the terminal depth and a grab groundwater sample at the terminal depth; • 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 will be collected using a 4-foot long by 2.25-inch diameter MacroCore sampler with a 4-foot long acetate liner, which was advanced by the direct-push drill rig using 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. A lengthwise section of each acetate liner was removed with a splitting tool to expose the soil. The soil column was 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) calibrated to isobutylene. 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 Page 3 PARTNER