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~ooaosso~ feed line for Load Line 4, all the pipes inspected were constructed of metal. The northeast water main feed line was constructed of transite. Transite is a term for asbestos.containing cement. The pipe was not tested for asbestos content, but is assumed to contain asbestos. All field tests for explosives were negative and all water supply lines were left in place with the excavations backfllled. (c) Approximately 7,9401inear feet of vitreous clay industrial and sanitary sewers were excavated and removed from the building footprints to the fenced boundaries of the load. line. The sewer lines were removed up to a safe distance from the building footprints to preserve the structural integrity of the buildings, with approximately 1,800 linear feet of sewer line left in place to be removed later. At the fenced boundary the sewers were capped as they exited the load line. (d) Along with the utilities that were known from the as-built drawings, previously unknown utilities that were discovered during geophysical investigation were inspected and field screened for explosives. One of these pipes is described as a buried culvert pipe insulated with asbestos. The insulation was sampled and analyzed and determined to contain 40% amosite asbestos. This pipe runs from the east perimeter fence to the location of former Building L-10 within Load Line 4. Through visual inspection and field screening, it was determined that the pipe did not contain any explosives residues and the line was left in place with the excavation backfilled. (e) Limited sail screening was conducted beneath sewers, at an abandoned cesspool location, and beneath anomalies identified in the geophysical survey to confirm that the lacations did not contain greater than 10% explosives. Results for nearly all samples were below the quantitation limit, that is, no detectable level of explosives was found. The highest value detected was 0.00066% RDX (6,600 µg/kg) in a single sample. Because these results were far below the value that is considered. an explosive safety hazard (greater than 10% explosives is considered to be an explosive safety hazard), the soils beneath the sewer lines were left in place. (f) During the July 2005 1to 2006 time frame, work was performed to disassemble, decontaminate and demolish Load Line 4 buildings; remove concrete floor slabs; sample the soil under former concrete slab lacations to confirm that the locations did not contain greater than 10% explosives; and to excavate and remove sanitary and industrial sewer lines that were close to building foundations, followed by limited sail screening for explosives at the greater than 10% level beneath former sewer locations. The highest concentration of explosives detected during soil screening beneath the former slabs was 580,000 µg/kg 2,4,6-TNT or 0.058%. The highest concentration of explosives detected during soil. screening beneath the former sewer locations was 340 µg/kg 2,4,6-TNT. (g) The goal of all of the above-identified actions from 2005 to 2006 was to obtain SX certification for the load. line areas in accordance with U.S. Army Pamphlet IOCP 385-1 Classification and Remediation of Explosive Contamination. The SX designation indicates that 9