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11 September 2001 AGE-NC Project No. 98-0466 ' Page 7 of 24 ' summarized in Table 1,the vertical distribution of analytes in SCA2 are shown on Figure 6.A report of procedures and findings for the December 2000 investigation is in preparation. A boring in the immediate steam cleaning area is not proposed as the area has been assessed;however two proposed ' borings (PB5 and PB6) along the down-stream reach of the western ditch are proposed to assess ground water for TPH, chromium, lead and zinc potentially released from the steam cleaning operation. The P135 boring can also be used to assess soil and ground water for contaminants ' potentially released from the saw filing room as discussed in Section 3.4.4. ' 3.2.3. Western Drainage Ditch AGE collected a total of six soil samples from the western ditch area during the site assessment of ' June 2000.TRPH was detected in all samples,but was particularly eleva ed in sample DS 1-2,which also had elevated concentrations of chromium, lead and zinc. ThE chromium concentration (663 mg/kg)exceeds the Preliminary Remediation Goal(PRG)for industrial soil of 450 milligrams ' per kilogram(mg/kg).The lead concentration(357 mg/kg)exceeds the California modified PRG of 130 mg/kg, but does not exceed the federal EPA PRGs for either residential or industrial soil. Although zinc concentrations are elevated in DSI-2 (1,730 mg/kg), the level does not exceed any ' PRG for the metal. A deeper sample could not be retrieved from hand-auger boring DSI, but the concentrations of each analyte decrease northward, where the concentrations also decrease with ' depth. Also, deeper soil samples from probe boring DPl, located nearby, did not contain elevated metals or TRPH concentrations. Analysis of two samples collected in the ditch area for pentachlorophenol and tetrachlorophenol showed no detectable concentrations.Contaminants detected in DS 1-2 were TRPH,chromium,lead and zinc. TRPH in DS 1-2 was characterized as motor oil. TRPH and lead concentrations dropped ' significantly from 2 feet bsg to 5 feet bsg in DS-2. Chromium and zinc were at background concentrations in DS2-5.Analytical results are summarized in Table 1.Figures 6 and 7 illustrate the extent of TRPH-and metals-impacted soil.Two borings(PB5 and PB6)are proposed to be advanced along the down-stream reach of the western ditch are proposed to asses ground water for TPH-all, chromium, lead and zinc potentially released from the steam cleaning perations. The PB5 boring can also be used to assess soil and ground water for contaminants poten ially released from the saw ' filing room as discussed in Section 3.4.4. ' 3.3. SEPTIC TANKS A total of 6 septic tanks have been identified on the subject property,of hich only two are currently ' active. The active septic systems are located on the north and east portio of the property(Figures 3 and 4),one east of the existing maintenance building,the other west of the Millwork Building. The inactive septic tanks are on the south portion of the site (Figure 3), one east of the former Cover ' Advanced GeoEnvironmental,Inc.