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demonstrates conclusively that this has occurred. The model also predicts that any gasoline leaked from the Kwikee UST's will also migrate eastward, and the most contaminated wells will be located east of the UST's (KF-2 and KF-4). Less contamination will be detected west of the facility, as at KF-3. For the most part, this prediction is not supported by the data. The highest TPH-g concentrations detected at the Kwikee site have consistently been in KF-3, and TP11-g concentrations have been below the detection limit in KF-4 (Table 3). TPH-g concentrations in KF- 2 were intermediate between KF-3 and KF-4 through July 2000, but have been below the detection limit since then. For this reason, the Kwikee UST facility is not depicted as a source of significant soil or groundwater contamination in the model (Figure 11). This question is discussed further in subsequent sections. 3.0 HISTORICAL ANALYSIS OF GROUNDWATER FLOW DIRECTIONS In past reports, groundwater elevation maps have been produced separately by the consulting companies that monitor the two sites. Until 2000, maps of the Kwikee site were limited to the solution of a "three-point problem" using wells KF-1, KF-2, and KF-3. Such maps gave only a very cursory picture of the direction of groundwater flow, because the water table is seldom perfectly planar and the actual flow direction can vary significantly at the scale of the area being mapped. Attempts to integrate the data from the Chevron site were unsuccessful, partly because the two sites were not monitored concurrently but even more so because the elevations of the well casings (and in some cases the well locations themselves) were not accurately surveyed across both sites. Groundwater elevation maps prepared by Upgradient Environmental since the sites were jointly surveyed in late 2001 encompassed both sites, but revised maps were not prepared for previous quarters using the new survey data. Therefore, during the data analysis for this report, depth-to- groundwater measurements for all wells were used in conjunction with the new survey data to produce at least twenty groundwater elevation maps dating back to 1994. Of these, ten have been selected for inclusion in this report. Because the Kwikee site was not monitored as consistently as the Chevron site, data at Kwikee were available only for selected quarters, and these were the preferred maps for display here. One map is shown for each year from 1995 through 2001, and three maps are shown for 2002. The analysis demonstrates that groundwater flow since 1994 has been generally consistent with the schematic model derived from the regional groundwater elevation map (Figure 6), but there have been local variations, both spatially and 'temporally. The primary flow direction was to the northeast, but varied at times from north to south and was locally even westward prior to the installation of the remediation system at the Chevron site. 3.1 Year 1: 1995 The groundwater elevation in August 1995 is depicted in Figure 12. Chevron wells MW-10 through 12 and Kwikee wells KF-4 through 7 had not yet been drilled, so data are absent along the north and east margins of the map. The most prominent feature of this map is the strong east-northeast 12