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1 <br /> 26 October 2004 <br /> AGE-NC Project No 97-0290 <br /> Page 3 of 6 <br /> 24 SOIL-VAPOR SAMPLING AND ANALYSIS <br /> A set of soil-vapor samples were collected from the carbon-adsorption soil-vapor extraction system <br />' on 15 January, 23 February, 24 March, 28 April, 26 May, 22 June, 22 July, 19 August and one <br /> sample was collected from the SVE system on 16 September 2004 <br />' The soil-vapor samples were collected in Tedlar vapor bags using a vacuum pump attached to the <br /> influent and effluent stream The samples were labeled,placed in apre-chilled cooler and transported <br /> under chain of custody to McCampbell Analytical Inc (MAI) and CTEL, California DHS-certified <br />' laboratories The samples were analyzed for <br /> • TPH-g in accordance with EPA Method 8015M, and <br />' BTEX and MTBE in accordance with EPA Method 8021B <br />' 3.0. FINDINGS <br /> Ground water elevation,flow direction and gradient were determinable this quarter,the contaminant <br /> impact to ground water was quantified from the ground water laboratory data <br />' From field and laboratory data collected at the SVE remediation system from 30 December 2003 to <br /> 16 September 2004 AGE determined the average TPH-g concentration, the average flow rate and <br />' calculated the approximate mass and volume of hydrocarbons removed <br />' 3 1 GROUND WATER ELEVATION AND GRADIENT <br /> On 09 September, depth to ground water at the site ranged from 49 42 feet to 54 46 feet below the <br /> top of the well casing (btoc) in monitoring wells MW-4 and MW-2, respectively(Table 1) <br /> Ground water elevation at the site ranged from 2 16 feet to 2 66 feet below mean sea level (MSL) <br />' in monitoring wells MW-2 and MW-6, respectively (Table 1) Ground water elevation in the <br /> monitoring wells decreased an average of 2 feet from the elevations recorded during the May 2004 <br /> monitoring event A ground water elevation contour map for the September 2004 monitoring event <br />' is illustrated on Figure 3 The ground water gradient for the September 2004 event was calculated <br /> to be 0 002 ft/ft to the south and southwest, which is consistent with historical ground water flow <br /> directions <br /> 1 Advanced GeoEnvironmental,Inc <br /> I <br />