SITE INFORMATION AND CORRESPONDENCE

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I can agree that the groundwater gradient has shown a typical pattern of variability with seasonal changes. After review of the previous quarterly monitoring reports, I note that the flow direction has varied from approximately west by northwest to north by northeast, a variation of nearly 90 degrees. However, I have found no data which would suggest that the flow direction has ever been in a more easterly direction than north by northeast. Given this information, it is logical to suggest that the current position of monitoring well 3A, is In the ideal location to intercept a contaminant plume which might emanate from the historical tank pit and travel in a northeasterly direction. As the data indicates, monitoring well MW-3A has always shown non- detect for all constituents. I honestly cannot perceive of a location within the vacant lot which would be an improvement on this location. 3. Time frame for well monitoring. The concern seems to center on the possibility that four quarters of groundwater monitoring may not be sufficient time to detect a plume of contaminated groundwater, if one existed. Ms Deutsch has also stated an additional concern, that the physical presence of the monitoring wells constitutes an impediment to the development or financing of the site. Regarding the time frame of the monitoring program, I would like to point out that the only wells which have been in existence for more then three quarters have shown non-detect for more then two years. As stated previously, monitoring well MW-3A has always been non-detect, including the past four quarters. The only well to show any significant positive results during the entire monitoring period, was well MW-3, which was destroyed during the over-excavation project when the surrounding contaminated soils were removed. I would also point out that the removal of the accumulated groundwater from the tank pit during that excavation also had a positive effect on the remediation of the low level hydrocarbons which had previously been reported in MW-3. Another concern referred to the fact that the vacant land was sporadically used for automobile storage. Ms. Deutsch suggested that there may have been "dumping" on the property during the active life of the service station. On these issues, it must be pointed out that in Unocal's considerable history of operating and remediating service stations, I do not know of a single instance of environmental degradation caused by the simple act of parking or storing automobiles. I have no information which would suggest that auto repairs, dismantling or "auto wrecking" was ever undertaken on this lot. In addition, there is no physical evidence, such as, surface staining, to suggest that any dumping or other activities took place. Regarding the physical presence of the monitoring wells, I can assure Ms. Deutsch from personal knowledge that there are literally thousands of sites located throughout California which are the subject of ongoing groundwater monitoring programs. As you are well aware, the majority of developers and lending institutions are familiar with the routine monitoring requirements of state and local governments. In addition, Ms. Deutsch should be assured that in cases such as this (where soil closure has been obtained and only monitoring requirements remain), there is not a significant impediment to either the development or the financing of the property. She should