SITE INFORMATION AND CORRESPONDENCE

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RE-MANUFACTURING LTD. -4- 19 February 1991 SOIL AND GROUND WATER ASSESSMENT REPORT According to the ground water surface profile determined for October through December 1990, all three wells are "upgradient" of the SI (SI) and wells MW-2 and MW-3 are upgradient of Moore Industrial Park property. However, MW-1 is adjacent to the SI and would probably be influenced by any leakage from the SI. Appendix E contains Piper and Stiff diagrams for the three wells. The diagrams indicate the water chemistry in MW-3 is different from MW-1 and 2. The TDS in wells MW-1, 2 and 3 were 919, 625, and 1,500 mg/L, respectively. These exceeded the recommended secondary MCL of 500 mg/L. The highest TDS was found in MW-3 which is farthest away from the SI and may be influenced by an off-site source. 6. Drill, log, and analyze additional soil borings to locate ND or background levels of contaminants in both the horizontal and vertical directions. The number, location, depths of these borings, and sampling intervals shall be approved the Regional Board prior to drilling. No additional borings have been drilled in or near the SI, except for MW-1 . No extractable TPH, volatile organics, or phenols were detected in the soil samples Kleinfelder submitted for analysis. However, as previously mentioned, two samples collected by the Board from MW-1 at 25 and 30.5 feet below ground surface contained 1 .46 mg/kg and 1.21 mg/kg dichloromethane, respectively. All of the total lead results from the well borings were near or below the detection limit of 5 mg/kg. The maximum total lead concentration was 6 mg/kg. Two of the samples were analyzed for soluble lead. Both were below the detection limit of 0.5 mg/L. Kleinfelder collected surface samples from the floor and sidewalls of the SI after Re-Manufacturing excavated roughly 120 cubic yards of soil . The results are included in the 14 December 1990 Closure Plan. The results show hazardous levels of lead, up to 62,700 mg/kg, remain in the SI . Therefore, additional soil borings are required in order to locate NO or background levels of contaminants, as stated above. 7. Prepare a 3-dimensional picture of the subsurface showing the lateral and vertical extent of contamination. This cannot be completed until the extent of contamination has been determined. 8. Based on your qualified assessment of the data, graphically show where you have determined that these contaminants attenuate to ND or background levels. This cannot be completed until the extent of contamination has been determined. 9. Explain any inconsistencies in the data such as the apparent isolated occurrences of phenol in the vadose zone, and the order of magnitude increase in TEH between 10 and 15 feet bgs found in borehole No. 2. Page 2 of the SGWA report states: "Based on the results obtained during this soil and ground water assessment, it does not appear that the SI has affected soil more than a few feet below the SI. " This may be true for lead, based on the borings sampled by Hunter and Associates on 24 August 1989. However, the inconsistencies mentioned above must still be addressed.