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Page 2 of 5 <br /> Communications with Ecology under the VCP are included in Task 6. <br /> Task 2:Remedial Investigation Field Explorations <br /> 1. Update GeoEngineers' health and safety plan for on-site field work. <br /> 2. Contact the public utilities notification service to mark public utilities in the exploration areas, <br /> rights-of-way and easements. In addition, we will subcontract a private utility locating company to mark <br /> underground utilities or obstructions. <br /> 3. Monitor the completion of up to ten direct-push borings to depths up to 10 feet below ground surface <br /> (bgs) and four hollow-stem auger (HSA) borings to depths up to 25 feet bgs. The explorations will be <br /> completed by a licensed drilling company under subcontract to GeoEngineers. Explorations locations will <br /> be recorded in the field using a hand-held GPS device. <br /> 4. Complete the HSA borings as permanent 2-inch-diameter monitoring wells. The monitoring wells will <br /> extend to approximately 10 feet below the apparent seasonal low groundwater level, which is presumed <br /> to range between approximately 10 and 15 feet bgs;the actual depth may vary based on field screening <br /> results and observed groundwater conditions during drilling.The well will be screened with 0.010-inch or <br /> 0.020-inch slot width polyvinyl chloride (PVC) well screen spanning the zone of water table fluctuation <br /> and extending into the vadose zone. Silica sand will be placed in the borehole annulus surrounding the <br /> well screen and the annulus will be sealed above the sand with bentonite and concrete to ground surface. <br /> A concrete well monument will be fitted with a locking cap within flush-mounted well monument and <br /> locking steel monument lid.The drillers will submit resource protection well notification and construction <br /> documents to Ecology as required by State law. Develop the monitoring well by a combination of surging <br /> and purging. <br /> 5. Obtain soil samples at approximately 2.5-foot depth intervals from the explorations for field screening <br /> and possible chemical testing. Field screen the soil samples for evidence of volatiles using visual, water <br /> sheen and headspace vapor screening methods.Visually classify the samples in general accordance with <br /> ASTM International (ASTM) D 2488 and maintain a detailed log of each exploration. <br /> 6. Submit one to three soil samples from each boring for chemical analyses of polycyclic aromatic <br /> hydrocarbons (PAHs) by U.S. Environmental Protection Agency (EPA) Method 8270 and diesel and <br /> oil-range petroleum hydrocarbons by method NWTPH-Dx. Additionally, select soil samples will be <br /> submitted for chemical analysis of gasoline and BETX by EPA Method 8021B,volatile organic compounds <br /> (VOCs) by EPA Method 8260, and MTCA 5 Metals by EPA 6000/7000 series. Chemical testing will be <br /> performed on a standard 10 business day turnaround time by an Ecology-certified environmental <br /> laboratory under subcontract to GeoEngineers. The selection of samples for chemical testing will be in <br /> accordance with the Ecology-reviewed RI Work Plan. <br /> 7. Survey the monitoring well casing rim elevations relative to a local control point. Measure depth to <br /> groundwater and evaluate the groundwater flow direction. <br /> 8. Obtain up to four rounds of groundwater samples from the monitoring wells using low-flow sampling <br /> techniques. Submit the water samples for chemical analysis of PAHs, diesel and oil-range <br /> petroleum hydrocarbons, gasoline-range petroleum hydrocarbons, volatile organic compounds, and <br /> MTCA 5 metals. Both filtered and unfiltered water samples will be submitted for analysis of total and <br /> dissolved metals. Prior to sampling, the wells will be purged until water quality parameters stabilize <br /> and/or three well volumes are removed. Chemical testing will be performed on a standard 10 business <br /> day turnaround time by an Ecology-certified environmental laboratory under subcontract to GeoEngineers. <br /> GeoEngineers,Inc. <br /> File No.0661-108-02 <br />