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1 C,eolagualTechuacsW Page 6 Morita Additional Site Characterization Report Project No 724 2 April 19,2004 ' ❑ Benzene, toluene, ethylbenzene and xylene (BTEX)by EPA method 8020 ❑ Methyl tertiary butyl ether(MTBE) by EPA method 8020 ' ❑ Gasoline range petroleum hydrocarbons (TPH-G) by EPA method 5030/8015(m) A summary of the groundwater laboratory data is attached in Table 1, Appendix A, and the lab data reports are attached in Appendix B ' As required under A132886, the MW-202 laboratory data were submitted electronically to GeoTracker on March 2, 2004 - confirmation number 4792362451 ' Wells MW-111111, MWA 08/208, MW-109/209 and MWA 10/2_10 Del-Tech Geotechnical Support developed the rest of the new wells on January 24, 2004 ' All of the new and existing wells will be sampled during the first quarter 2004 groundwater monitoring event that was performed by Del-Tech on March 22, 2004 4.0 GEOLOGY AND FIELD OBSERVATIONS The results of the borehole installations are summarized below ' Well MW-202 Well MW-202 was installed adjacent to well MW-2 that was installed by a previous consultant MW-2 was logged primarily as silts, silty sands and clayey silts to its total depth of 65 feet bgs Well MW-202 was sampled at five foot intervals at 60 feet and below The subsurface is characterized as follows ❑ The subsurface contained alternating layers of clayey silts, sand, sandy silt and silty ' sand ❑ The soils tended to be blue-grey in color with a faint organic odor that was described as "sewage odor"by the field geologist ' ❑ When present, the sands were recorded as very fine to medium grained, with occasional grains to 3mm ❑ The 65 and 75 feet bgs samples contained prominent CaCO3 nodules, with the 80 feet bgs sample containing Iess CaCO3 ' ❑ Field evidence of contamination (odor) was noted in all samples from this boring OVM readings from samples ranged 0 1 0 3 ppm above the background level of 0 ppm ' Wells MW-111111 Shallow and intermediate well pair MW-111111 was installed in the sidewalk on the northwest edge of the parcel This is an up gradient position with two known UST sites across Charter Way to the northwest of the site These wells will enable a determination if ' off site contamination is migrating onto the site The subsurface in this location is characterized as follows ❑ The subsurface contained alternating layers of silty clays, sands, silts and clays ' ❑ Sand intervals occur at 20 - 25 feet bgs ❑ The sands ranged from very fine to very coarse grain size and brown to grey or blue- grey in color CaCO3 nodules and black organic detritus or magnetite were ' occasionally present ❑ Fine grain units- silts and clays were found at depths of approximately 0 — 15, 30 — 60 feet bgs 1