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First Quarter 2006 Groundwater Monitoring Report Eckert Cold Storage,Manteca,California Page 2 Summary of March 29, 2006 Quarterly Groundwater Monitoring Event Field Activity Number of monitoring wells8 Number of monitoring wells sampled 2 Number of monitoring wells measured for 6 Date monitored 03/29/06 water level Site H drolo" Average depth to groundwater below Increase(+)/decrease(—)in average depth to - 1.18 ft monitoringwell measuringpoints 15.12 ft groundwater since last monitoringevent shallower Approximate oundwater flow direction North Groundwater Contamination Well;containing free product 0 Wells with petroleum hydrocarbon odors noted I Nature of contamination: Gasoline Range in concentrations: Constituents Benzene(pg/L) <0.5—62 Toluene(µg/L) <0.5—2.7 Ethyl benzene(µg/L) <0.5—66 Total Xylenes(µglL) <1,0—97 TPH-G(mg/L) 0.081-1.2 MTBE(µgll,) 1.3-7.7 1,2-DCA(µg/L) <0.5—5.6 TBA /I.. <5.0—27 FIELD OBSERVATIONS As per the first quarter monitoring schedule, a Condor representative visited the Site on March 29, 2006 to sample three of the eight Site monitoring wells (MW-1, MW-5, and MW-8) and measure water levels in all the eight monitoring wells. However, the Condor representative observed a large soil stockpile covering most of the north end of the parking lot, including monitoring wells MW-4 and MW-8. Thus, Condor's field observations were limited to monitoring wells MW-1 and MW-5, and groundwater measurements taken at all Site monitoring wells except for inaccessible wells MW-4 and MW-8. The Condor representative noted that the traffic box cover for monitoring well MW-1 had been removed and appeared to have been scraped off with a tractor/scraper. Although the traffic box appeared to be damaged,the well casing itself appeared to be intact. Field observations included sample odor, appearance (color, clarity, and presence of petroleum product sheen or phase in samples), and water quality field parameters. The inspection samples from both monitoring wells MW-1 and MW-5 appeared to be clear in color with good clarity. No sheen was noted in the samples collected from both wells; a slight hydrocarbon odor was noted in the inspection sample collected from MW-1. GROUNDWATER ELEVATIONS six of the eight Site monitoring wells were measured for depth to water during the first quarter 2006 monitoring event conducted on March 29, 2006. The average groundwater elevation was approximately 1.18 feet higher than the previous monitoring event conducted on January 5, 2006. Monitoring wells MW-3, MW-4, and MW-6 are typically the three wells used to calculate the groundwater gradient at the Site. Because the soil stockpile prevented the depth to water in monitoring well MW-4 from being measured, monitoring wells MW-5, MW-6, and MW-7 were selected to calculate an estimated groundwater gradient of 0.0011 to the north(see Figure 3,Attachment A). Historically, groundwater gradient direction at the Site has been variable but generally to the northwest. Groundwater elevation data for the March 29, 2006 monitoring event are presented in Table 1, on the following page. } ilk CONDOR