COMPLIANCE INFO - Laserfiche WebLink

Home Browse Search

WORK PLAN FOR LIMITED SITE INVESTIGATION lierracon Tracy Ridge Tracy, California March 27, 2019 Terracon Project No. NA187052.1 Five soil borings will be advanced using hand auger in the upper 5 feet bgs then by a track- mounted, direct push drill rig to a depth of 10 feet bgs. Drilling activities will be performed by a California C-57 licensed driller. During drilling activities, soil samples will be continuously collected to document lithology, color, and relative moisture content. In addition, the soil samples will be field screened using sensory methods and an organic vapor meter (OVM) equipped with a photoionization detector (PID) to detect the presence of organic vapors. One soil sample from each of the 23 borings will be collected for laboratory analysis from the zone exhibiting the highest PID reading or the interval of most-likely environmental impact as determined in the field by the sampling professional. Additional soil samples may be collected from the intervals exhibiting a change in lithology, and/or from the bottom of the boring. These soil samples will be placed on hold for potential contingent analyses if recommended based on review of the initial analytical results. The soil samples will be collected and placed into laboratory-prepared containers. The containers will be labeled and placed on ice in a cooler which will be secured with a custody seal. The samples and completed chain-of-custody forms will be transported to the selected analytical laboratory for analysis within 5-day turnaround following receipt of the samples by the laboratory. At the completion of boring activities, if groundwater is encountered, groundwater samples will be collected. The sample containers will be subsequently transported to Pace Analytical, a California state- certified laboratory, under strict chain-of-custody procedures. 2.6.2 Boring Abandonment Terracon will schedule the backfilling inspection with the SJCDEH no later than 48 hours prior to planned field work activities to ensure the availability of an SJCDEH representative. Additionally, Terracon will confirm the field work date and inspection time with the inspector 24 hours prior to field work. At the completion of sampling activities and in the presence of an SJCDEH representative, the soil borings will be backfilled using neat cement. A tremie pipe will be lowered to within three feet of the bottom of the boring and the cement slurry will be deposited into the borings via the trennie pipe. If located over asphalt, the cement will be dyed using cement color packs to match existing surface. Responsive • Resourceful • Reliable 5