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. remediation system was shut down in March or early April, and is one of the most obvious examples of plume response to changes in groundwater flow direction of any documented in this report. As a further confirmation of this response, MTBE was detected in KF-2 at more than 2 ppb (this elevated detection limit had not been exceeded since August 1998). The contours are consistent with downgradient dispersion of MTBE, parallel to groundwater flow in the eastern portion of the Kwikee site. Furthermore, the increase in concentrations in all wells favors the interpretation that the previous decrease in concentration (February) was due more to plume rotation than to overall reduction in the dissolved mass of MTBE (see above paragraph). 5.0 NOVEMBER 2002 MONITORING REPORT 5.1 Procedures Groundwater monitoring took place on November 14, 2002. Gettler-Ryan Inc. monitored the neighboring Chevron site on the same date and provided water-depth measurements and a copy of the laboratory report to Upgradient Environmental. After the wells were opened and allowed to equalize with atmospheric pressure, the depth to groundwater was measured with a water level meter and recorded on the Well Monitor Report (Appendix Q. A Grundfos submersible purge pump was then used to purge the wells of standing water. Ten to 15 gallons of water were purged from each well and stored in 55-gallon drums on • site. After purging, water samples were collected with a disposable plastic bailer and placed in 40-m1 vials. The vials were labeled and, logged and placed in a cooled ice chest for later transport to Sequoia Analytical Laboratory. The laboratory report and chain of custody form are in Appendix D. 5.2 Results The static water level fell by over 2 feet since the second quarter, and the depth to groundwater now averages more than 10 feet. This is a typical seasonal decline prior to the start of the rainy season. The historical record of groundwater depth measurements is given in Table 2, and the analytical record is presented in Table 3. Both of these have been discussed in previous sections of this report. 6.0 ADDITIONAL ITEMS OF CONCERN In written correspondence in September, EHD offered several points for consideration and further analysis. These are addressed below. ® EHD pointed out that: "The results from one sampling event, in an area of known contamination, are hardly definitive. As an example, the last time the ground water 1 21