WORK PLANS - Laserfiche WebLink

Home Browse Search

Revised Workplan-Additional Site Investigation for PFAS BSK Project E20-016-01F Stockton Metropolitan Airport(SCK) March 1, 2023 Stockton, California Page 17 6.1.2.1 Soil Sampling Subsurface soil samples collected with a DPT drilling rig will be recovered inside acetate core sleeves. Soil cores will be opened after retrieval for analytical sample collection using laboratory supplied sample bottles. Alternatively, if the samples are cut directly from the acetate liner, the sample interval will be selected,cut out using a clean hack saw(or similar cutting tool)and capped with tight fitting vinyl endcaps, then labeled with relevant sample information (i.e., sample ID, date, time, analysis, etc.,). Teflon sheets will not be used under the vinyl end caps. Following sample acquisition, the remainder of the acetate sleeve would be opened, and soil logged according to ASTM D2487-17, the Unified Soil Classification System (USCS) and screened with a Photoionization Detector(PID). Subsurface soil samples for chemical analysis will be collected during advancement of the monitoring well and vertical groundwater definition borings with a HSA drilling rig using a Modified California or Standard Penetration Test (SPT) split-barrel sampler lined with new,steel sample sleeves and will be placed in a laboratory supplied sample container. Soil from the monitoring well borings, and borings advanced for vertical groundwater sampling will be collected continuously for the entire depth of the boring using a Modified California or SPT split-barrel sampler lined with new, steel sample sleeves. Subsurface soil samples from the monitoring well borings will also be logged according to the USCS. Lithologic classifications and observations will be recorded on a drilling log and a monitoring well construction log (see Appendix A-A of the SAP). The following information will generally be recorded on the soil sampling logs: • Depth (total and any other relevant depth information) • USCS classification (ASTM D2487-17) • Color • Moisture content(i.e., dry, moist, wet, saturated) • Density(relative to soils found on site) • Depth to groundwater, if encountered • Indications of contamination, if any • Other observations as needed The following approximate depth intervals are proposed for collection of subsurface soil samples for chemical analyses in the shallow DPT, Monitoring wells, and vertical groundwater definition borings: • 1.0 ft bgs or directly beneath pavement, if present • 5.0 ft bgs • 10.0 ft bgs In addition to the sample intervals listed above, DPT borings BSK plans to advance to depths greater than 10 ft bgs for vertical definition of soil will be sampled for chemical analysis every 5 ft,once the 10 ft sample has been collected (i.e., 15 ft, 20 ft, 25 ft, etc.,) down to the total depth (e.g., 40 ft bgs) of the boring. DPT borings advanced to a depth greater than 10 ft bgs in PRA 1 will be located near the former boring B-19