EST performed multiple phases of soil gas monitoring and direct-push soil sampling at Air Force Plant (AFP) 42, Palmdale, California, for a national environmental consulting and engineering company. Multiple sites within AFP 42 were investigated as part of a final remedial investigation performed for the Air Force Installation Restoration Program. The objectives of soil gas monitoring and direct-push soil sampling were to identify potential vadose zone source areas of volatile organic compounds (VOCs) and assess the lateral and vertical extents of VOCs in soil. Environmental assessment activities and EST’s involvement with the AFP 42 project is ongoing.
Sites were investigated using soil gas surveys and direct push soil sampling methods, including open, unpaved burn areas, unlined drainage ditches, tarmac, and asphalt-paved runway areas (some covered with Marsden-matting). Fieldwork was performed in Level D personnel protective equipment (PPE), with provision for Level C PPE upgrade if warranted by field conditions. EST field personnel collected approximately 500 soil gas samples at AFP 42. Each of the soil gas samples were analyzed onsite for halogenated (HVOCs) and aromatic hydrocarbons (BTEX) using EST’s mobile environmental laboratories. As a special project requirement, the soil gas sample analyses were performed using a 30-minute to 1-hour turnaround time to facilitate real-time decisions in the field. Soil samples were collected by EST field staff at locations and depths specified by the client.
Soil gas sample analyses were performed according to DTSC/LARWQCB guidance documents. Analytical QA/QC procedures included recovery of surrogate compounds, multi-point equipment calibrations, laboratory control samples, daily mid-point calibration checks, and blank injections. Fieldwork was performed without incident or accident. Each phase of this project involving EST was completed on schedule and within budget.