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30 May 2000 <br /> AGE-NC Project No. 97-0372 <br /> Page 10 of 17 <br /> a grab ground water samples difficult. A shallow zone of `boulders', if horizontally <br /> widespread, could act as a preferred horizontal migration route for impacted fluids during <br /> periods of high ground water elevation. <br /> • Sample water produced from the municipal water well and analyze for metals, VOCs. <br /> Plating Bath Areas <br /> • Steam-clean concrete walls and flooring in the plating bath area, the solder flux room and <br /> the treatment area; capture and contain all water generated; obtain swipe samples from the <br /> concrete for analysis for the target metals. Cleaning the walls and flooring is necessary to <br /> obtain an occupancy permit; capturing and containerizing the rinsale is necessary for proper <br /> disposal of the potentially impacted rinsate. <br /> • Advancement of four soil borings, three stepping out in unassessed directions from boring <br /> B7 and a deeper boring adjacent to B7 to obtain soil and ground water samples to analyze <br /> for the target metals and pH to determine the extent of impacted soil. Soil samples will be <br /> collected in the step-out borings at 2 feet, 5 feet bsg and then at 5-foot intervals to total <br /> depth, expected to be 30 feet bsg. Samples will start being collected at 10 feet bsg in the B7 <br /> twin boring. In addition, a grab ground water sample will be collected from the B7 twin <br /> boring. All soil samples and the grab ground water sample will be analyzed for pH; the <br /> 2-foot and bottom soil samples and the grab ground water sample will initially be analyzed <br /> for the target metals. As noted in Section 2.2 above, the drilling log for the California Water <br /> Service well on the adjacent site shows yellow clay from near surface to 26 feet below <br /> surface grade (bsg); from 26 feet to 30 feet bsg the log shows boulders. The boulders, if <br /> present on the subject property, may make obtaining the proposed total depth and a grab <br /> ground water samples difficult and could provide a preferred horizontal migration route for <br /> impacted fluids during periods of high ground water elevation. <br /> • Advancement of one soil boring adjacent to the floor drain in the eastern portion of the <br /> material preparation area to obtain soil samples to analyze for the target metals and pH. The <br /> floor drain provides a potential vertical migration route into the subsurface for releases in the <br /> area. The boring will be advanced to a total depth of 15 feet bsg with samples to be collected <br /> at 2 feet, 5 feet, 10 feet and 15 feet bsg. All samples will be analyzed for pH, the 2-foot <br /> sample will initially be analyzed for the target metals. <br /> • Advancement of one soil boring in the former solder flux room to obtain soil samples to <br /> analyze for the target metals and pH. Depth of boring, sampling points and analyses are the <br /> same as noted above for the floor drain area. <br /> • Conduct a fluorescence survey for lead in the solder flux room, steam-clean the solder flux <br /> room,and obtain wipe samples from walls and floors for analysis for lead, copper and nickel. <br /> Advanced CeoEn,ironmental,Inc <br />