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the water table. Therefore actual or potential contaminant <br /> transport pathways exist into the groundwater and possibly <br /> into the air from these SWMUs. Table 2 shows a compilation <br /> of the results of analyses for some metals of concern in <br /> groundwater samples from the second quarterly monitoring <br /> round. Many are over EPA and DHS MCLS. These excursions <br /> over MCLs need to be highlighted and potential pathways <br /> explained in the risk assessment. <br /> 12 . SWMU No. 20 is listed as an aboveground solvent tank within <br /> Building 10, according to a Canonie report (1988) on <br /> Industrial Waste System Point Source Investigation. Also in <br /> Building 10 other possible contributing facilities have been <br /> identified. These other facilities include a paint spray <br /> booth inside the northwestern corner connected to a paint <br /> booth tank outside the northwestern corner. Wastes <br /> generated there include heavy metals, ethylbenzene, xylene, <br /> SVOCs, total petroleum hydrocarbons (TPHs) , and reactive <br /> sulfides. Appropriate sampling/analysis need to be <br /> proposed. <br /> Within the northeastern corner of the building were a steam <br /> cleaner and a cleaning tank (removed) ; outside of that <br /> corner is a sewer manhole which receives and temporarily <br /> stores wastes from the cleaning tank, the paint spray booth <br /> and the steam cleaner. Wastes reported in the AEPCO, Inc. <br /> report included TCE, 1, 1, 1-trichloroethane (1, 1, 1-TCA) , <br /> SVOCs, virtually all heavy metals, TPHs, reactive sulfides, <br /> and some organochlorine pesticides. <br /> All of this discussion points to the need for additional <br /> sampling and analysis around the northern end of Warehouse <br /> 10. <br /> SOIL SAMPLING AND ANALYSIS <br /> 13 . Slant-borings have been proposed as the soil sampling <br /> approach in several of the SWMU areas. Due to the <br /> limitations of the angle of approach of the slant boring, <br /> samples more representative of the contaminant migration in <br /> the subsurface at a consistent level under the various SWMUs <br /> would be collected using a horizontal boring technique. <br /> Several techniques are available and perhaps should be <br /> considered. Such techniques may involve first digging a <br /> vertical trench into which the horizontal boring equipment <br /> might fit. Consideration of such a technique is suggested <br /> for the Sanitary Settling Ponds (SWMU No. 2) , the IWPs (SWMU <br /> No. 3) , the Storm Pond (SWMU No. 4) , and Burn Pit No. 1 <br /> (SWMU No. 7) . <br /> 14 . The confidence level, power, minimum detectable relative <br /> difference, and the coefficient of variation (CV) must all <br /> I-4 <br />