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STANDARD OPERATING PROCEDURES The following section describes field techniques that are performed by Stantec personnel in the performance of the tasks involved with this project. LOCATING UNDERGROUND UTILITIES Prior to the commencement of work on site, field personnel marks the boring locations with white paint and research the location of all underground utilities with the assistance of Underground Service Alert(USA). USA contacts the owners of the various utilities in the vicinity of the site to have the utility owners mark the locations of their underground utilities. In addition, a private utility locator is subcontracted to further locate possible underground utilities in each of the boring areas. Prior to drilling, each boring is advanced manually using a hand auger or post-hole digger to a minimum depth of 8 feet to avoid contact with unmarked utilities. SOIL BORING AND SOIL SAMPLING PROTOCOL Drilling and soil sampling are performed under the direction of a Stantec registered geologist or engineer. During drilling, the soil Iithology is classified and described using the Unified Soil Classification System (USCS). All down-hole drilling and sampling equipment is decontaminated prior to use and between each boring to reduce the chances of cross contamination. The sampler is washed between each sampling event to reduce the potential for cross contamination between samples. Hand augers are washed between each sampling event to reduce the potential for cross contamination between boreholes. Soil sampling is performed using a sampler at approximately 5-foot intervals. Using hollow- stem auger or direct-push methods, the soil sampler is advanced ahead of the casing to the desired depth to collect a discrete depth soil sample. The sampler is then retrieved protecting the integrity of the hole. At the next sample depth interval, a new sampler is lowered into place, and advanced further to collect the next soil core. Soil core samples are collected in the sampler with clear acetate expendable liners or stainless steel sleeves. The portion of the sample to be retained for potential laboratory analysis, if warranted, is cut from the soil core, sealed with a Teflon liner and a plastic cap, labeled, identified on the chain of custody, and stored in a chilled cooler for transport to the laboratory. Remaining soil in the sampler is used for screening with a photoionization detector (PID) or equivalent equipment. The soil field screened with a PID is placed in re-sealable plastic bags and allowed to reach ambient temperature. Headspace vapors in the bags are field screened with a calibrated PID. The highest observed stable reading is then recorded onto the boring log.