ARCHIVED REPORTS_QUARTERLY REPORT - THIRD QUARTER 2005

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24 October 2005 AGE-NC Project No. 98-0500 Page 3 of 11 2.1. SOIL-VAPOR EXTRACTION PARAMETERS/ANALYSIS The SVE system was operational between 14 June and 12 September 2005 (3`d Quarter 2005), operating for approximately 2,094 hours. The SVE well network setting (number and type wells) remained the same between(the 2nd and 3`d)quarters,and vacuum was optimized at increased vapor wells that had significant detections of hydrocarbon vapor. These included extraction wells on the eastern portion of the site with organic vapor meter (OVM) readings generally over 100 parts per million(ppm)and extraction wells(vapor and monitoring wells)within the Connell Lift Truck well network. The SVE system was observed weekly and monitored monthly.Weekly activities included collection and storage of soil-vapor condensate in 55-gallons drums for storage and disposal, and recording system operation parameters, including hours of operation, system temperatures and flow rates. At each monthly monitoring event,the flow rate of extracted soil-vapor(influent)was measured using an electrical DPT flow meter,a manual DPT flow meter to verify the electrical readings,and vacuum potential was measured using a Dwyer magnehelic vacuum gauge.The organic-vapor concentration was measured at the influent and effluent sampling ports using an OVM equipped with a photo- ionization detector(PID [Thermo Environmental 580, 10.0eV,calibrated to isobutylene 100 ppb]). Three sets of soiil-vapor samples were collected, on 28 July, 18 August and 12 September 2005. Samples were collected from the influent and effluent ports directly into Tedlar vapor bags using a vacuum chamber and vacuum pump. The samples were labeled, placed in a pre-chilled cooler and transported under chain of custody to Cal Tech Environmental Laboratory(CTEL)both California Department of Health Services(DHS)-certified analytical laboratories. The samples were analyzed for: • Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA Method 8015 Modified and • Benzene, toluene, ethylbenzene and total xylenes (BTEX); with methyl tertiary-butyl ether (MTBE) in accordance with EPA Method 8020 or 8260. 2.2. SOIL-VAPOR EXTRACTION RESULTS The SVE unit operated at generally consistent operational rates during the observation period. Extraction flow rates were calculated at 280 cfm.An induced vacuum(negative pressure)of above 20 inches of water was measured in the piping between the blower and extraction wells. Soil-vapor extraction data is presented in Table 1. • Advanced GeoEnvironmental,Inc.