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A4OM 4 FIELDWORK INSTRUCTION 4.1 UTILITY CLEARANCE A utility clearance will be completed prior to installation of soil vapor probes. For more information, see Utility Clearance SOP100. • A large area (as available) will be cleared by the utility locator to allow installation at multiple locations • Plans detailing ground penetration sites and depths, including client provided site plans, will be provided to the Sub-Surface Clearance Contractor for site clearance activities. 4.2 PROBE INSTALLATION PROCEDURE 4.2.1 Real Time Monitoring During Installation If the bores are being installed in a potentially contaminated area, the air quality will be monitored using a PID and LEL. 4.2.2 Installation Steps • Wipe the permanent soil gas probe clean. • Confirm probe was stored in a clean manner; if requiring decontamination prior to sampling, conduct decontamination and allow probe to dry prior to sampling. • Confirm Teflon tubing is dry. • First, hand augur to at least 5 feet bgs. After confirming that there are no underground utilities, continue drilling the borehole to the targeted terminal depth using the chosen drilling method (i.e., direct push). • Perform logging of the soil, even for shallow wells. • Take a photograph to show the depth of the hole and location. • Take PID readings of soil at the depths at which the implants are to be installed. If elevated PID readings are observed, call the PM to discuss the need to move the vapor bore location vertically or laterally to achieve optimum results. • Once at target depth, expose the probe's slotted head by lifting the outer sleeve of the probe so that the tip of the probe (attached to the internal tubing) detaches from the probe; this leaves a vapor `screen' of approximately 4 to 6 inches. • Maintain a good seal around the top of the probe (i.e. between the probe and soil). Note: Non Destructive Digging (NDD) cannot be utilized for soil vapor bores, as the introduction of air or water can compromise sample integrity.