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Site Background Information
<br /> Eckert Cold Storage,Manteca,CA
<br /> February 8,2005
<br /> Page 4 of 5
<br /> Condor conducted the third quarter 2003 groundwater monitoring event at the site on September 2 and 3,
<br /> ' 2003 Groundwater samples were collected and submitted for laboratory analyses from monitoring wells
<br /> MW-4, MW-8, and domestic well DW-1 No separate phase petroleum was noted in the wells, but a slight
<br /> petroleum odor was noted in groundwater recovered from MW-8 The groundwater samples collected
<br /> ' from the monitoring wells and the domestic well were analyzed for BTEX, TPH-G, and selected gasoline
<br /> oxygenates/additives including MTBE Laboratory analytical results for the September 2 and 3, 2003,
<br /> monitoring event were generally consistent with historical laboratory analytical results
<br /> ' The average groundwater elevation was approximately 2 37 feet lower on September 2, 2003, than the
<br /> previous sampling event conducted on June 5, 2003 Water level data from monitoring well MW-7 was
<br /> not included in the September 2, 2003 figures Water level measurement of monitoring well MW-7 was
<br /> ' obstructed by a root mass in the casing The root mass in monitoring well MW-7 was removed on
<br /> September 3, 2003 by using a small diameter auger The groundwater elevation contours estimated with
<br /> the depth to water measurements indicated the groundwater gradtent was generally towards the northwest
<br /> ' The groundwater gradient estimated using MW-4, MW-5, and MW-6 was 0 0020 ft/ft towards the
<br /> northwest, and was generally consistent with historical groundwater gradients estimated for the site
<br /> ' Condor conducted annual groundwater monitoring on December 12, 2003 during the fourth quarter 2003
<br /> groundwater monitoring event at the site Groundwater samples were collected and submitted for
<br /> laboratory analyses from annually monitored wells MW-5 and MW-7, as well as from quarterly
<br /> monitored wells MW-4, MW-8, and domestic well DW-1 No separate phase petroleum, sheen, or odor
<br /> was noted in the field inspection samples collected from the wells Monitoring well MW-5 was observed
<br /> to have a damaged monument, and the well casing appeared to be broken dust below the ground surface
<br /> Groundwater samples collected from the monitoring wells and the domestic well were analyzed for
<br /> ' BTEX, TPH-G, and selected gasoline oxygenates/additives, including MTBE Laboratory analytical
<br /> results for the December 12, 2003, monitoring event were generally consistent with historic laboratory
<br /> analytical results
<br /> ' The average groundwater elevation was approximately 0 10 feet lower on December 17, 2003 than the
<br /> previous sampling event conducted on September 2, 2003 The groundwater elevation contours estimated
<br /> ' with the depth to water measurements indicated the groundwater gradient was variable but overall
<br /> towards the northwest The groundwater gradient estimated with a three-point construction using wells
<br /> MW-3, MW-4, and MW-6 was 0 002 ft/ft towards the northwest, and was generally consistent with
<br /> ' historic groundwater gradients estimated for the site Condor recommended that monitoring well MW-5
<br /> be repaired and resurveyed, or destroyed
<br /> Condor conducted the first quarter 2004 groundwater monitoring event at the site on March 17, 2004
<br /> Eckert personnel indicated repairs to monitoring well MW-5 had been made prior to the first quarter 2004
<br /> groundwater monitoring event with no apparent change in elevation to the well measuring point
<br /> Groundwater samples were collected and submitted for laboratory analyses from monitoring wells MW4,
<br />' MW-8, and domestic well DW-1 No separate phase petroleum was noted in the wells, but a slight
<br /> petroleum odor was noted in groundwater recovered from MW-8 The groundwater samples collected
<br /> from the monitoring wells and the domestic well were analyzed for BTEX, TPH-G, and selected gasoline
<br />' oxygenates/additives including MTBE Laboratory analytical results for the March 17, 2004, monitoring
<br /> event were generally consistent with historical laboratory analytical results
<br />' The average groundwater elevation was approximately 1 11 feet higher on March 17, 2004 than the
<br /> previous sampling event conducted on December 17, 2003 The groundwater elevation contours estimated
<br /> with the depth to water measurements indicated the groundwater gradient was variable but overall
<br />' towards the northwest The groundwater gradient estimated with a three-point construction using wells
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