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CHECKLIST OF REQUIRED DATA FOR NO FURTHER ACTION REQUESTS AT <br /> UNDERGROUND TANK SITES <br /> Barnyard Site, 8960 W Walnut Grove Rd, Thornton, CA <br /> Page 1 <br /> 1 Distance to production wells within 2,000 feet of the site Up to seventeen water supply <br /> wells were identified within 2,000 feet of the site The closest water supply well is <br /> approximately 280 feet northwest of the site as depicted on the Figure in Attachment A <br /> Additional details on these and others wells within 2,000 feet of the site can be found in the <br /> Groundwater Monitoring Well Installation Report (Ground Zero Analysis, Inc , August 9, <br /> 2001) <br /> 2 Site maw Site maps depicting the location and layout of the site (including buildings and <br /> streets), former USTs and associated excavation locations, soil stockpile locations, soil boring <br /> locations, monitoring well locations, groundwater gradients are included in Attachment A <br /> 3 Cross sections and figures depicting lithology Cross sections and logs of soil boring and <br /> monitoring wells that illustrate site stratigraphy are included in Attachment B <br /> 4 Stockpiled soil Approximately 3,750 cubic yards (cy) of soil generated from excavation <br /> and drilling activities was stockpiled on site Approximately 1,100 cy of clean overburden <br /> and soil reported as being non-detectable for petroleum hydrocarbon constituents through <br /> laboratory analysis was utilized for backfill Approximately 2,650 cy of soil impacted with <br /> low to moderate levels of petroleum hydrocarbons was aerated to non-detectable levels <br /> The remediated soil remains on site <br /> 5 Monitoring wells remaining on site fate Seven monitoring wells (MW1-MW7) remain at the <br /> site It is recommended that these wells be properly destroyed by pressure grouting with neat <br /> cement once site closure is granted <br /> 6 Tabulated results of groundwater elevations and depths to water A table of groundwater <br /> elevation data is included in Attachment C Depths to water at the site have ranged from <br /> approximately 5 26 feet below grade to 9 74 feet below grade <br /> 7 Tabulated results of all sampling and analyses, including detection limits for confirmation <br /> sampling and analyses Analytical data for all soil and groundwater samples are summarized <br /> in the tables included in Attachment C <br /> S Concentration contours of contaminants in soil and groundwater <br /> The extent of soil and groundwater contamination remaining at the site is very limited A <br /> cross-section showing contaminant concentrations in the soil is included in Attachment D A <br /> Figure showing the estimated lateral extent of groundwater contamination is included in <br /> Attachment D <br /> 9 Zone of influence for remediation system Not applicable <br /> appB cklist doc <br />