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S E C ® R w • Ms Victoria McCartney March 24, 2005 Page 6 • Soil Analytical Results. Soil samples from MW-11 and MW-12 were collected at 5- foot intervals using a California modified split-spoon sampler Selected samples from each boring were sent under chain-of-custody procedures to Severn Trent Laboratories, Inc (STL) for analysts of gasoline range organics (GRO), BTEX, fuel oxygenates (MtBE, TAME, di-isopropyl ether [DIPE], ethyl tertiary butyl ether [EtBE], TBA), 1,2-dichloroethane [1,2-DCA], and ethylene dibromide [EDB] by EPA Method 8260B Results are presented in Table 2 Soil samples were inadvertently not analyzed for TPHd by—EPA Method-8015M, as requested by the SJCEHD in correspondence dated December 23, 2003 (Attachment 1) Procedures for soil sample collection are included in Attachment 3 The certified laboratory analytical report and chain-of-custody documentation are presented in Attachment 5 r • Well Development. The newly installed groundwater monitoring wells were developed on January 24, 2005 by Cascade under the supervision of SECOR personnel Each well was developed by surging the length of the screen interval and removing at least ten casing volumes of water Well development field data sheets are included in Attachment 6 ® ; Groundwater Analytical Results Groundwater monitoring wells were sampled after well development on January 24, 2005, and were submitted to STL for analysts of GRO, BTEX, fuel oxygenates (MtBE, TAME, DIPE, EtBE, TBA), 1,2-DCA, and EDB by EPA Method 82608 Results are presented in Table 3 The certified laboratory analytical report and chain-of-custody documentation are included in Attachment 6 Samples will be collected from these wells under standard groundwater monitoring and sampling protocol during the first quarter 2005 sampling event Well Surveying Wells MW-11 and MW-12 were surveyed by Morrow Surveying, Inc (Morrow), a licensed surveyor, for locations and elevations relative to mean sea level Well survey data is included 1n Table 1 and Attachment 7 l FINDINGS Subsurface Conditions Soil within the boring for well MW-11 consisted of sandy silt from ground surface to approximately 11 feet bgs, underlain by sand to the depth of the boring (approximately 30 feet bgs) Soil within the boring for well MW-12 consisted mainly of sandy silt, with a layer of well graded sand between approximately 10 and 15 feet bgs, and a saturated clay layer from approximately 16 to 19 feet bgs Saturated sand was encountered at the total depth of the boring (approximately 30 feet bgs) Groundwater was first encountered in the two borings at approximately 13 feet bgs, and stabilized at approximately 11 5 to 12 75 feet bgs (Table 3) 1 1ConocoPhrilipslRetad Sdes1111931Reports111193 Off-Site Well Install 1-05 doc St;COR International Inco poorated