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conceritration of benzene (0.008 mg/L) was found in MW3 . The toluene level was highest in EA2 ( 0. 0025 mg/L) , xylenes in MW1 ( 0.007 mg/L) , and ethylbanzene in .7A4 (0.002 mg/L) .- 3 . 3 DISCUSSION OF THE RESULTS AND CONCLUSIONS No hydrocarbons were detected in the soil samples collected during the most recent investigation. Water %from the three sold wells located around the former tank field (MW1 , MW2, and MW3 ) and from two new wells (EA2 and EA4 ) contained�.detectable.amounts of hydrocarbons or some gasoline volatile consjtu`etts-. The concentrations of dissolved hydrocarbons are low, and have decreased significantly since March 1387 (Table 2 ) . The concen- tration of benzene in the old wells dropped by amounts ranging from 10 times (MW3 ) to over 500 times (MW1 ) from March 1987 to - . February 1988 . This decrease and the low levels of hydrocarbons suggests that fuel losses were of limited ,yolume at on the site,. and that ground water has probably never been in direct -contact with free product. It appears tha'C there is no remaining significant source of hydrocarbons at the site. Therefore, hydrocarbons already disso' •ed in the ground water will be further diluted, volatilized, and degraded, so that their concentrations should drop below the detection limit within the next year if the pre- sent trend continues. The shift of ground-water direction .from northwest to southwest in the period February--April 1988 was probably caused ray more intensive pumping from nearby domestic and industrial wells, especially one located at the Broadway Hatchery. The southwest flow direction appears to be induced by a local cone of epres_ Sion rather than a shift in regional flow. The difference between the regional and the local direction of ground-water movement implies that vicinity water supply wells have a measur- able influence upon the direction of ground-water movement at the C23/72q2 9