ARCHIVED REPORTS_DRYWELL CLOSURE AND INVESTIGATION

Home Browse Search

1 NOA Drywell Closure and Investigation Page 10 of 26 May 30, 2014 was recorded, labeled and stored at a temperature of approximately 4°C in an ice chest for I transportation to the analytical laboratory. Two (2) pre-chilled, pre-labeled 40-ml VOA vials with Teflon septa were filled for TPH as Diesel testing. The sample was preserved with hydrochloric acid. Collection methods specified for volatile organics were followed. The sample was recorded, labeled and stored at a temperature of approximately 40C in an ice chest for transportation to the analytical laboratory. I Two (2) pre-chilled, pre-labeled 40-ml VOA vials with Teflon septa were filled for Total Recoverable Petroleum Hydrocarbons (TRPH) testing. The sample was preserved with hydrochloric acid. Collection methods specified for volatile organics were followed. The sample was recorded, labeled and stored at a temperature of approximately 4°C in an ice chest for transportation to the analytical laboratory. 4.3.2 Soil For the soil sampling in the drywells, a truck-mounted drill rig equipped with an eight-inch hollow-stem auger was used to collect the soil samples under the supervision and direction of a California Professional Geologist or Engineer. Drilling fluids were not used. A 24-inch long core barrel fitted with four (4) six-inch long clean stainless steel sleeves were forced into the undisturbed soil one (1) to two (2) feet below the bottom of the drywells (50 feet bgs). The core barrel was then retrieved and sampling sleeves were removed and placed on clean plastic. The borehole was logged once soil sampling began using cuttings and the coring by a Geologist in accordance with the Unified Soil Classification System. The sampling sleeve ends were then covered with Teflon sheets and plastic end caps and secured with silicone-based tape. Sample end caps were labeled appropriately. Sealed and labeled samples were then placed in cooled ice chests for transportation to the analytical laboratory. 4.4 Sample Documentation 4.4.1 Sample Labeling Each sample was marked with identification details, including the sample identification number, date and time of sample collection, sample matrix, whether the sample is preserved or unpreserved, signature of sampler, and the general analysis to be conducted. Soil samples were labeled according to the drywell, the depth of sample collection, and the sampling tube collected. For soil samples, DW-1 is referred to BS since it was the first boring 1 drilled. The sampling tubes are ordered using roman numerals, with the bottom sample labeled I. For example, the bottom tube collected from DW-1 at sixty-five (65) feet bgs is labeled B1@65'-I. Groundwater samples were labeled according to the drywell and the sample collection order. For groundwater samples, DW-1 is referred to as W1 since it is the first well in which groundwater was sampled. For example, the first groundwater sample collected from the western drywell was labeled Wl-I. '044 902 Industrial Way• Lodi, CA 95240•209.367.3701 • Fax 209.333.8303 02014 Neil 0.Anderson&Associates, Inc.