SITE INFORMATION AND CORRESPONDENCE

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iJWl1'ViTA Site Code'_'193 Healy Property Pa3e petroleum hydrocarbons) and Tank #2 had 3.1 ppm TPH. Both are below state action levels. No further action required by the Health District at this time." Based upon this assessment by County Health the property was purchased by Mr. Northcutt. It would appear from the Public Health Services letter of October, 1991 that there has been some change in the interpretation of "allowable limits as recommended by the leaching potential analysis in the LUFT manual." Table 2-1 on Page 29 of this October 1989 LUFT Manual presents the leaching potential analysis estimations rationale and the maximum allowable TPH levels which can be left in place. The subject site scores as follows: 1. Depth to groundwater: 25 - 50 feet = 5 points 2. Fractures in subsurface: none = 10 pmts 3. Average annual precipitation 10 - 25 inches = 9 points 4. Man made conducts which increase vertical migration none = 10 points 5. Unique site features, recharge area, coarse soil, nearby well — 9 pgints Total = 43 points Based on the subjective score noted above, the allowable TVPH level for this location should be 100 mg/kg. In considering this type of analysis, however, it must be recognized that the LUFT manual is only a guidance document and not a substitute for technical reasoning based on experience or other relevant data. For instance, while concern is justified based on the presence of a well approximately 130 feet across gradient from the location, this is mitigated by the fact that their are two wells (part of 7-11 investigation) completed in shallower water bearing zones approximately 90 and-210 feet directly down gradient of the former tanks. Both of these wells have recorded nondetectable levels of all gasoline hydrocarbons over a 6 year period of continuous sampling, much of it, during a time when pumping from this shallow zone was occurring on the downgradient 7-11 property (which would draw upgradient contaminants to these wells). Additionally, the reported TPH Ievels recorded in the Ivy Motel well (upon which the County file review was based) were anomalous based on a very long history of sampling including the last 6 monthly samples. These very occasional rounds of anomalous results have been reported for several wells in the area which are monitored by Southland Corp. (7-11). Clearly Health Services accepts this since no remediation or investigation in the vicinity of these wells has ever been suggested. Furthermore, the site conditions for the LUFT scoring categories (which are necessarily crude) of depth to water (40 feet) and precipitation (14 inches) are in the lowest 20% of the scoring range. KPL692.RW1