SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

S E C O R Ms, Devra Lewis January9, 2004 Page 4 FINDINGS -ADDITIONAL EXCAVATIONS A private utility locator was contracted to locate the ends of the steel pipelines located in the original excavations. However, the utility locator equipment frequently lost the signal after it passed a connection or elbow in the pipelines. Thus, several excavations were required to locate the ends of the steel pipelines. The ends of pipelines were located in three locations and additional pipelines were located as well. Findings from each of the additional excavations are presented below. Excavation and pipeline locations are shown on Figure 2. Photographs are provided in Attachment B. EX-1-A1: This excavation was performed in an area where the utility locator lost the signal from one of the steel pipelines located at the east end of EX-1. The three four-inch diameter steel pipelines located at the east end of EX-1 were located in this excavation at a depth of approximately 52 inches bgs; however, the ends were not located (photo 11). Soil encountered consisted of fill material (clay with rocks and concrete). Gray hydrocarbon staining was observed in the excavation beginning at a depth of approximately 36 inches bgs. EX-1-A2: This excavation was performed in an area where the utility locator lost the signal from another of the steel pipelines located at the east end of EX-1. The three steel pipelines located at the east end of EX-1 were located in this excavation at a depth of approximately 64 inches bgs. Each pipe was connected to a 90 degree elbow that continued the trend of the pipes to the west. The three pipelines were located on top of each other after the 90 degree turn (photo 12). Soil encountered consisted of fill material (clay with rocks, bricks, and concrete). Gray hydrocarbon staining was observed in the excavation beginning at a depth of approximately 36 to 48 inches bgs. EX-1-A3: This excavation was performed in an area where the utility locator lost the signal from the steel pipelines located at the east end of EX-1-A2. The open end of one of the three steel pipelines located in EX-1-A2 was located at a depth of approximately 59 inches bgs. Approximately 3 to 4 inches of soil filled the end of the pipe. The soil was removed from the end of the pipe and was stained more than the surrounding soil, very wet (the surrounding soil was dry), had PID of 177 ppm, and exhibited an oily sheen when placed in water. The two remaining pipelines from EX-1-A2 were not located (photos 13 through 16). Soil encountered consisted of fill material (clay with concrete, wood, and asphalt). Gray hydrocarbon staining was observed in the excavation beginning at a depth of approximately 36 inches bgs. EX-1-B1: This excavation was performed in an area where the utility locator lost the signal from the steel pipelines located in the middle of EX-1. The excavation was located adjacent to EX-1-A2 and the two eight-inch diameter steel pipelines that were located in the middle of EX-1 were located in this excavation at a depth of approximately 60 inches bgs, with 90 degree elbows that trended the pipes to the west (photo 17). Soil encountered consisted of fill material (clay with rocks, bricks, and concrete). Gray hydrocarbon staining was observed in the excavation beginning at a depth of approximately 36 to 48 inches bgs. EX-1-B2: This excavation was performed in an area where the utility locator lost the signal from the steel pipelines located in EX-1-B1. The two eight-inch diameter pipelines located in EX-1-B1 were not found, however seven additional pipes (described below) were located (photos 18 and 19). Soil encountered consisted of fill material (clay with rocks, bricks, and concrete). Gray hydrocarbon staining was observed in the excavation beginning at a depth of approximately 24 to 36 inches bgs. Stockton Parcel 2A Utility Search Report