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a-1 APPENDIX A - MAXIMUM ACCEPTABLE LEVELS <br /> Table 2-1 (LOFT Manual, 1989) - <br /> Leaching Potential Analysis for Gasoline and Diesel <br /> V Using Total Petroleum Hydrocarbons(TPH) = �_ <br /> and Benzene, Toluene, Xylene and Ethylbenzene (BTX8E) <br /> The following table was designed to permit estimating the concentrations of TPH and BTX8E that can be <br /> left in place without threatening groundwater. Three levels of TPN and BTX8E concentrations were derived <br /> (from modeling) for sites which fall into categories of low, medium, or high leaching potential. To use the <br /> table, find the appropriate description for each of the features. Score each feature using the weighting <br /> system shown at the top of each column. Sum the points for each column and total them. Match the total <br /> points to the allowable BTX8E and TPH levels. <br /> S SCORE S' SCORE S SCORE <br /> SITE C 10 PTS C 9 PTS C 5 PTS <br /> O IF CON- O IF CON O IF CON- <br /> FEATURE R DITION R DITION' R DITION <br /> E IS MET E 1S MET E IS MET <br /> Minimum Depth to Groundwater from the > 100 51-100 5 25-50' <br /> Soil Sample (feet) <br /> Fractures in subsurface (applies to 10 <br /> None Unknown Present <br /> foothills or mountain areas) <br /> Average Annual.Precipitation (inches) < 10 10-25 26-402 <br /> Man-made conduits which increase 10 None Unknown Present <br /> vertical migration of leachate <br /> =Uniqessoitie features: recharge area, 10 None At least More than <br /> nearby wells, etc. lone .one <br /> COLUMN TOTALS —r TOTAL POINTS <br /> RANGE OF TOTAL POINTS 49 pts or more 41 - 48 pts 40 pis or less <br /> MAXIMUM ALLOWABLE 1/50/50/50 .3/.3/1/1 NA' <br /> B/T/X/E LEVELS (PPA <br /> MAXIMUM ALLOWABLE GASOLINE 1.000 100 10 <br /> TPH LEVELS (PP" <br /> DIESEL 10,000 1.000 100 <br /> N ' If depth is greater than 5 feet and less than 25 feet, score 0 points (If depth is 5 feet or less, this table <br /> should not be used) <br /> 2 If precipitation-ts over 40 inches, score 0 points <br /> 3 Levels for BTX8E are not applicable at a TPH concentration of 10 ppm (gasoline) or 100 ppm (diesel) <br /> (For explanation see step.6, page 27 (of the LUFT Manual)) <br /> NOTE: Minimum depth to groundwater must be historic high <br /> County or Los Angeles, Department of Public Works, UST Local Oversight Program; -Guidelines for Report Submittals.-June 1923 <br />