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<br /> TheSo Report
<br /> The Southland Corporation,9110 Thornton Road M
<br /> Stocon CA December S.19955
<br /> Monitoring well MW-1 was selected as the primary test well Radius of capture,velocity and flow rate
<br /> obtained from the test for MW-1 are considered to be generally representative for the entire site
<br /> Applied vacuum at the wellhead was approximately 20 5 inches of water (IW) Induced vacuum at
<br /> wells MW-4, PW-3, MW-3,VP-4, 17A,VP-3,VP-2, MW-2,VP-1 and MW-5 located at distances of 15,
<br /> 24, 27, 28, 40, 40, 49,60, 77 and 120 feet, respectively, ranged from 1 2 to 0 1 IW Total petroleum
<br /> hydrocarbon concentration in the extracted air was two percent LEL Velocity of extracted air in the
<br /> 4-inch vapor extraction piping was 950 feet per minute (ft/min) Oxygen concentration in the extracted
<br /> air was 12 2 percent volume Data collected during the tests are summarized in Table 2
<br /> Wells MW4, PW-3,VP-4, MW-3,VP-3, VP-1,VP-2, MW-2, PW-2, MW-8, MW-10, MW-12 and MW-5
<br /> were also tested, however, during the tests on these wells,induced vacuum was not monitored due to
<br /> time constraints Concentration of total petroleum hydrocarbons in extracted air from these wells
<br /> measured in the field ranged from zero to two percent LEL
<br /> Laboratory analysis of air samples collected during the tests indicated that the only BTEX component
<br /> detected was xylenes and it was detected only in extracted air from wells MW-4,VP-2 and MW-12 at
<br /> concentrations of 2, 0 5, and 0 6 micrograms per liter(pg/L), respectively TPH-G was detected in
<br /> samples collected from wells MW-1, MW-4,VP-3,VP-1,VP-2, MW-2, MW-8, MW-10, MW-12 and
<br /> • MW-5 at concentrations ranging from 18 to 74 pg/L (Table 3)
<br /> Vacuum at the extraction well (MW-1) and induced vacuum readings at observation wells MW-4, PW-3,
<br /> MW-3,VP-4, 17A,VP-3,VP-2, MW-2,VP-1 and MW-5 were plotted against distance of the observation
<br /> wells from the extraction well (Figure 11) Based on the data discussed above,the radius of capture of
<br /> MW-1 at an applied vacuum of 20 5 IW was determined to be approximately 100 feet (Figure 12)
<br /> Results of the test were used to estimate potential hydrocarbon mass extraction rate should the SVE
<br /> system be reactivated Flow rate obtained during the test using a 1 5-hp blower was approximately 83
<br /> cubic feet per minute (ft3lmin) Based on this flow rate and an average TPH-G concentration of 39
<br /> pgIL, the potential maximum hydrocarbon mass extraction rate was estimated as follows
<br /> 83 ft' a�x 39�m TPH-G x 28 32 L x 9 Ib x 1440 min = 0 29 lbs TPH-G
<br /> min L air fe 454xleAV day day
<br /> The results of the SVE test conducted at this site indicated that hydrocarbons were present in the
<br /> vadose zone soil or in the capillary fringe at this site, however, based on the laboratory analytical results
<br /> . of air sampling,the estimated quantity was small
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