REMOVAL 2011 CLOSURE IN PLACE - Laserfiche WebLink

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' data from former wells on the Subject Property, groundwater is expected to be approximately 65 feet below ground surface (bgs). Soil encountered within the area of excavation was predominantly a silty clay. ' 2.3 Post-UST Closure Activities ' The following sections provide a summary of tasks performed following in-place closure of the UST. ' 2.3.1 Soil Sample Collection On October 26, 2011, PSI advanced two angled hand-auger borings (B-1 and B-2) at ' the two ends of the closed UST (See Figure 3). The soil borings were advanced underneath and a soil sample was collected from the two ends of the UST. Each boring was then advanced beyond the initial sample and a second soil sample collected Soil ' samples were collected in B-1 at 7 and 8.5 feet bgs and in B-2 at 8.5 and 9.5 feet bgs. Soil samples were collected with a drive sampler lined with a new stainless-steel sleeve. Upon retrieval of the soil samples, the ends of the sample sleeves were covered with ' Teflon sheets and capped with polyethylene end caps. The samples were labeled and placed in a chilled cooler pending delivery to the laboratory for analysis. Soil samples were assigned identification numbers such as B-1-7, where B-1 indicates the boring number and -7 indicates that the sample was collected at 7 feet bgs. The samples were labeled with the sampling designation, depth, date, client name, and project number. All reusable soil sampling equipment was washed between samples with Alconox soap followed by a deionized-water rinse. Chain-of-custody procedures using chain-of- custody forms were used to document sample handling and transportation. A copy of ' the soil sampling procedure can be found in Appendix B. Following completion of the hand-auger borings, they were backfilled with hydrated ' bentonite chips. Soil sampling and backfill of the borings were conducted under the direction of Mr. Wong of the SJEHD. ' 2.3.2 Soil and Liquid Disposal ' PSI collected two soil samples each from two soil stockpiles (SP-1 and SP-2). The four samples were composited at the laboratory into two composite soil samples (SP-1-A&B and SP-2-A&B). The composite samples were analyzed for disposal characterization ' purposes. Based on the non-detect concentrations of Volatile Organic Compounds and trace concentrations of Total Petroleum Hydrocarbons as Diesel (TPH-D) in the stockpile soil samples, Mr. Wong of the SJEHD allowed the stockpiled soil to be used ' as backfill material at the site. During tank closure activities, approximately 100 gallons of residual diesel/water/soil were generated. The material was stored at the site in two 55-gallon drums, until it was removed by All Chem on November 22, 2011. The drums were transported to Clean Harbors Aragonite of Aragonite, Utah for disposal. A copy of the Uniform Waste ' Manifest is included in Appendix C. 3