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I Mr Harlan Knoll ' August 9, 2001 Page 3 of 7 ' 2.2 Drilling and Soil Sampling V&W Dnlling, Inc (V&W, C57# 720904) advanced four soil borings (MW 1 through MW4) at ' the site on May 17, 2001 for the purpose of installing groundwater monitoring wells Well locations are shown on Figure 3 ' V&W utilized a drilling ng equipped with hollow stem augers to advance the borings Soil samples were collected from borings MW 1 through MW4 at 5-foot intervals for classification and subjective evaluation of contamination An 18-inch long core sampler lined with new 2-inch ' diameter brass sleeves was used to collect soil samples The soil samples selected for laboratory analyses, based on held observations and field screening results, were sealed, labeled, immediately placed in an ice chest cooled to a temperature of approximately 4° Centigrade The samples were and transported under chain of custody to Argon Labs (FLAP #2359), where selected samples were analyzed for TPHg and TPHd using EPA method 8015M, benzene, toluene, ethylbenzene, and xylenes (BTEX) using EPA method 8020, and oxygenated gasoline additives, 1,2- ' dichloroethane (1,2-DCA), and ethylene dibromide (EDB) using EPA Method 8260B All work conducted at the site was performed under the supervision of Ground Zero geologist Sean Garvey and project manager John Lane, a California Registered Geologist Mr Harlan Knoll of PHS/EHD conducted grout inspections lie All dnlling and sampling equipment was decontaminated prior to use and between sample collection to minimize the possibility of cross contamination Soil generated during dnlling ' activities was placed on and covered with plastic sheeting Wastewater generated was placed in DOT approved 55-gallon drums Both waste streams are currently stored on site pending disposal 2.3 Well Construction ' Based on the lithology and initial depth to groundwater (8-11 feet bgs) encountered dunng drilling, wells MWI through MW4 were screened from approximately 4 feet bgs to 24 feet bgs The wells were constructed of 2-inch diameter, Schedule 40 PVC casing and 0 010 slot screen The filter pack ' consisted of 21 feet of 2112 silica sand The annular seal contained 2 feet of bentonite overlain by concrete, which was approved on site by Harlan Knoll of PHS/EHD The wells were completed with traffic-rated, grade-level well boxes Bonng/well construction logs are included in Attachment A 2.4 Well Development and Groundwater Sampling ' On May 21, 2001 a Ground Zero technician surveyed the well casing elevations, monitored groundwater levels, and developed and sampled groundwater from the newly installed wells 1 Prior to well development, the depth to groundwater was measured in each well and subtracted from the surveyed wellhead elevation to determine groundwater elevation The wells were lie developed by surging, bailing and pumping groundwater until turbidity was minimized During ' G 1Data1GROLJNDZE\Barnyard-Mamer�Repotts\WELLRPT doc