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it I Monitoring Well Installation Report Speedy Mart,8200 N Highway 99 • Page 5 of 8 the site on March 3, 2000 by American Valley Disposal and transported to a State-licensed waste disposal facility in Redwood City Copies of waste manifests for soil and liquid waste are included in Attachment C Domestic Well Investigation On February 28, 2000, Ground Zero personnel supervised Welenco in conducting a video survey of the water supply well to determine well construction details and evaluate the integrity of the well casing The down hole equipment, including the pump and 126 feet of piping, was removed from the well by Machado Pump on February 25, 2000 to allow access to the well The video survey determined that the well was cased to a depth of approximately 193 feet from the top of the casing (btc) with open hole from approximately 193 feet btc to 233 feet btc The top of the well casing stands approximately I foot above the ground surface No perforations were observed in the well casing The well pump was set at approximately 126 feet The well casing is in generally poor condition with numerous visible holes and/or poor joints between the depths of approximately 72 feet and 132 feet below the top of the well casing Very heavy scale was observed from approximately 160 feet btc to the total depth of the well casing • (193 btc) A copy written observations of the video survey is included in Attachment D A copy of a video tape of the well survey will be submitted under separate cover Groundwater samples were collected from the well immediately after the well survey at depths of 72 feet btc, 90 feet btc, and 222 feet btc These depths correspond to observations of a very poor casing joint (72 feet btc), a series of casing holes (81-101 feet btc), and near the bottom of the uncased hole (222 feet btc), respectively Samples were collected using disposable bailers equipped with check valves The groundwater samples were analyzed for TPHg, BTEX, and MTBE RESULTS OF INVESTIGATION Subsurface Conditions Soils encountered at the site during drilling consisted of primarily of silt and clay, with some sand The soil stratigraphy was dominated by silt and clay from the ground surface to approximately 30 feet bgs, with the exception of minor sand lenses in wells MW2 and MW3 at approximately 15 feet bgs The interval between approximately 30 feet bgs and 43 feet bgs consisted primarily of a laterally continuous layer of well graded to silty sand This sand unit was underlain by clay (SB5, MW2-MW4) and silt (SB4) to approximately 55 feet bgs A water bearing sand unit was encountered from approximately 55 to 63 feet bgs in every boring except for SB5, where clay was encountered Soil from approximately 63 feet bgs to 95 feet bgs consisted primarily of clay and silt with several minor sand .� lenses groundzeltuleburglwellrpt doe,