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t t- A S S O C I A T E S I N C The excavated backfill material will be immediately transported to Forward Inc. landfill in Stockton and stockpiled at the landfill. Composite soil samples will be collected from the excavated backfill material as it is loaded into the trucks for profiling at Forward Landfill. Five confirmation soil samples will be collected from the excavation at locations specified by PHS/EHD. Soil samples will be placed on ice and transported under chain-of-custody documentation to a State-certified laboratory for analysis. Samples will be analyzed for TPHg, TPHd, benzene, toluene, ethylbenzene, and xylenes (BTEX, EPA Method 8020), total petroleum hydrocarbons as Stoddard Solvents (TPHss, EPA Method 8015), chlorinated hydrocarbons (EPA Method 8010), oxygenate fuel additives (EPA Method 8260), and total lead. Once analytical results have been received, the data will be supplied to Forward Inc. landfill and they will place the soil in the appropriate location in the landfill based on the analytical results. The excavation will be backfilled with clean pea gravel from twelve feet to five feet bgs. The remaining five feet will be backfilled with clean Class II aggregate base material to the surface. The Class II material will be compacted as it is placed in the excavation. It is anticipated that the excavation, disposal, and backfill activities will be completed in one long day. Traffic control measures will be taken in the alley area to allow access for trucks and prevent public access to the excavation area. Advancement of Three Soil Borings To try and determine the.horizontal extent of soil and groundwater contamination, two soil borings will be advanced to approximately 57 feet bgs and completed as shallow groundwater monitoring wells. To try and determine the vertical extent of soil and groundwater contamination, one soil boring will be advanced to approximately 70 feet bgs inside the former excavation area. This boring will be completed as a shallow monitoring well and depending on field conditions, may be completed with a nested deep well. The proposed boring/well locations are shown on Figure 2. The three borings will be advanced using an 8-inch hollow stem auger equipped drill rig. A field geologist will be present to log all drill cuttings and soil samples. Descriptions of soil types encountered and sample collection intervals will be recorded on boring/well logs. Soil Sample Collection and Analysis Soil samples will be collected at five-foot intervals or changes in lithology, field screened with a PID, placed in a cooler with ice. At least two soil samples from consecutive five-foot intervals from each of the three borings will be submitted for laboratory analysis. Selected soil samples will be analyzed for TPHg, TPHd, TPHss, BTEX, chlorinated hydrocarbons, and oxygenate fuel additives. All drill cuttings will be drummed and stored on-site pending laboratory results. wA172951reportslwkpadd.doc 3