Laserfiche WebLink
09 September 2002 <br />' AGE-NC Project No. 98-0450 <br /> Page 5 of 6 <br />' 380 pg/l; the results of the laboratory analysis are summarized in Table 5. The laboratory.reports <br /> p s <br /> (MAI SarnpleNumbers:0203365-01,0204269-01,0205078-01 and0206031-07)Quality Assurance <br />' and Quality Control (QA/QC) reports and chain-of-custody forms are included in Appendices B <br /> and C. <br />' 3.4. MASS'OF RECOVERED HYDROCARBONS <br /> ' The hydrocarbon mass (TPH-g) removed during the operating period was calculated using the <br /> following equation: M= C•Q•t <br /> ' where: M = cumulative mass recovered (kg) <br /> C = soil-vapor concentration (kg/d) <br /> ' Q = extraction flow rate (rOhr) <br /> t = operational period, in hours <br /> ' The operational time was divided into four time periods. Mass of hydrocarbons removed was based <br /> on analysis of soil-vapor samples. The mass of extracted hydrocarbons was calculated for each time <br /> period using average hydrocarbon concentrations of influent soil-vapor sample data and average air <br /> tflow rates. <br /> Approximately 42 kg, 93 lbs or 14.5 gallons. of hydrocarbons as gasoline (TPH-g)'were extracted by <br /> ' the SVE system,at the site between March and June 2002. On average 1 ]b of gasoline was removed each <br /> day of operation. The volume/mass calculations are attached in Appendix D. <br /> 4.0. DISCUSSION AND CONCLUSIONS <br /> ' Based on SVE remediation data collected between March and June 2002 and the second quarter <br /> monitoring event, AGE concludes. <br /> ' Ground water was encountered in the monitoring wells at approximately 48 feet bsg and was <br /> inferred to have a southerly flow direction during the June 2002 monitoring event,consistent <br /> with the historical ground water flow direction. <br /> _ The maximum hydr`ocarbon concentrations in groundwater were detected in monitoring well <br /> BMW-4 at the former UST excavation;maximum BTEX concentrations were also detected <br /> ' in BMW-4. <br /> • MTBE was detected in two ground water samples (BMW-2 and MW-5).down-gradient of <br /> the former UST location. The maximum MTBE concentration was detected in sample MW-5. <br /> ' The average SVE inlet flow rate was 64 cubic feet per minute. Since re-initiation of the SVE <br /> Advanced GeoEnvironmentai,Inc. <br />