SITE INFORMATION AND CORRESPONDENCE_FILE 1

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b - _ Page 2 Geological Technics Inc. Marci Property Proj ect No.: 770.2 December 14,2001 ,- In May of 1996 a soil boring was advanced through the center of the former tank pit. BTEX, TPH-G and TEPH-D were detected in the soil samples collected down to a depth of 80 feet bgs. In March of 1997 SJC PHS/EHD requested the installation of an additional monitoring well. This well (MW-4) was installed in September of 1997. Soil and water sampled showed the presence of TPH-G and TEPH-D. In August 2001, GTI installed three additional monitoring wells at the site. Two wells, MW- 5 and MW-6, were completed as shallow wells screened across the water table at approximately 60 feet below grade. One well, MW-105, was completed with a discretely screened interval at approximately 30 feet below the water table. The new and existing wells have been sampled for four consecutive quarters and laboratory analysis of groundwater samples indicates the presence of diesel in the deep well. In our August 20, 2001, "2"d 'Quarter 2001 Groundwater- Monitoring". report, GTI recommended the installation of two additional deep monitoring wells. The purpose of these wells is to determine if there is a difference in shallow versus deep groundwater plume behavior. In their September 6, 2001 letter, the SJC PHS/EHD directed the submittal of a work plan to install additional deep-screened monitoring wells as described above. Proposed Direction of Project This opinion of cost includes the following work: I. Install two water table(70 ft) monitoring wells MW-7 and MW-8. 2. Install two deep (95 ft) screened monitoring wells MW-104 and MW-106. 3. Test a maximum of eight soil samples for BTEX, TPH-G, and TEPH-D. 4. Have a licensed land surveyor survey the top of casing elevations and locations of the wells into a benchmark elevation in accordance with the GeoTracker - Assembly Bill 2886 requirements. 5. Prepare a Site Characterization Reportdocumenting well installation activities and the results of laboratory analysis. 6. Develop the new monitoring wells. 7. Perform quarterly groundwater monitoring for one year. ❑ Test groundwater samples for BTEX, TPH-G, TEPH-D ❑ Test groundwater samples from MW-5 & 105 for Ethanol & Methanol for one event. ❑ Prepare quarterly groundwater monitoring reports. 8. Perform monthly depth to groundwater measurements to better define gradient trends. Listed below is a proposed schedule for implementing this project. I