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Geosyntec consultants • The HASP will be available on-site during all field activities. Prior to the start of field activities,a safety tailgate meeting will be conducted(Appendix G). 6.3.1.2 Soil Borings Soil borings will be drilled by a C57-licensed contractor using a direct-push technology (DPT) drilling rig under the supervision of a Geosyntec geologist or engineer. If refusal is encountered before the target depth of the boring is reached using DPT, then the hollow-stem auger (HSA) drilling method may be used to complete the boring to the target total depth (Table 9). The soil will be logged by field staff under the direction of a California Professional Geologist using the Unified Soil Classification System. The soil will be field screened using a 10.6 electron volt lamp photoionization detector(PID). Soil descriptions will include observations of chemical odors or staining. The borings will be terminated if the clay aquitard unit at approximately 70 to 80 feet bgs is encountered.All downhole equipment will be decontaminated prior to use. 6.3.1.3 Sample Collection Grab-groundwater samples will be collected from each DPT boring from the target depth intervals in Table 9. At each location, hollow steel direct-push rods equipped with a disposable tip and a section of slotted polyvinyl chloride (PVC) will be advanced to the selected depth (Table 9). The sample depths may be modified in the field based on the field conditions encountered. The sample depths may be adjusted to target higher permeability soils (i.e., sands and gravels). Additionally, the depth of first encountered groundwater, PID readings, and indications of chemical odors or staining may be used to adjust the sample depths.DTSC and the RWQCB will be notified if changes are made to the depths samples are collected based on the field conditions encountered. Once the bottom of the target sample depth has been reached, the rods will be retracted approximately 5 feet, exposing the slotted PVC screen while the disposable tip remains stationary. Groundwater samples will be collected with a new disposable polyethylene bailer or clean polyethylene tubing and peristaltic pump. The grab-groundwater samples will be labeled and stored in ice-cooled chests for transport under standard chain-of-custody procedures to a California certified laboratory for analysis of VOCs by EPA Method 8260B in accordance with the QAPP (Appendix H). RRI Groundwater Monitoring Work Plan 29 1 June 2018