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28 November 2005 AGE-NC Project No 00-0696 Page 3 of 5 water ranged from 4 69 feet(MW-4)to 5 74 feet(MW-1)below the tops of the well casings Ground water elevation at the site ranged from 17 45 feet (MW-4) to 17 68 feet (MW-3) below mean sea level (MSL), and averaged approximately 17 57 feet below MSL, indicating an increase in ground water elevation of approximately 0 16 feet since the last monitoring event in May 2005 During this monitoring event, the ground water level in well MW-4 was approximately 0 31 feet ' above the top of the well screen However, all wells should yield accurate data representative of shallow ground water conditions, during the purge cycle,the depth to ground water was reduced to a level within the well screen, thus recharging the well with water from the screen area exposed to the surrounding sediments and water-bearing layers During the August 2005 ground water monitoring event, ground water at the site was inferred to be flowing in a north-northeast plunging trough under hydraulic gradients of approximately 0 007 foot/foot(ft/ft)or less Figure 3 illustrates the contoured ground water elevations as measured on 23 August 2005 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH- was detected in the round water samples collected from wells MW-2 and MW-3 at g g concentrations of 100 micrograms per liter (µg/l) and 1,600 µg/1, respectively BTEX compounds were detected in the ground water samples collected from wells MW-2 and MW-3 at the following maximum concentrations in well MW-3 50 pg/l benzene,50 µg/l toluene,39µg/1 ethylbenzene,and 74 [ig/1 total xylenes MTBE was detected in samples MW-2 and MW-4 at concentrations of 85 µg/l and 14 µg/l, respectively No other analytes were detected at or above laboratory detection limits in the ground water samples analyzed The analytical results of the ground water samples collected on 23 August 2005 are summarized in Table 2 The laboratory report (CTEL Project No CT214-0508158), quality assurance/quality control (QA/QC)report, and chain of custody form are included in Appendix C 3 3 RESULTS OF SENSITIVE RECEPTOR SURVEY ' In August 2005, an AGE representative reviewed well drillers' reports from the California Department of Water Resources - Central District for water wells located in the surrounding area ' Drillers' reports for two water wells located within a 2,000-foot radius of the site were identified • Advanced GeoEnvironmental,Inc