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Pitch Reclamation Project -Sediment Control Embankment November, 2002 Based on the field observations made during the initial site visit, and subsequent discussions with Homestake, additional piezometers were installed in the embankment to further characterize the seepage through the embankment. A summary of the site observations and field work is presented in the following sections. Figure 4 shows the approximate location of the wet area of concern on the downstream face of the embankment and the location of the additional piezometers. 3.2 Field Observations -September 1, 2000 The site visit of September 1, 2000, included both observation of the embankment and slope conditions, and review of design and construction data contained in the project files at the site office. A summary of the significant observations and findings from the site visit is presented below. The complete report of the site observations and data, and resulting conclusions is included in Appendix A for reference. The embankment slope and crest areas were walked several times in noting the following observations. (Note: Left and right directions in this report are based on facing downstream.) I. The area of concern noted by the CDWR was evident by an azea of dense, tall grass (<10-ft diameter area) exists on the face of the slope. It was just below and to the left of the Standpipe for Piezometer No. 4 and about mid-slope near the maximum cross-section of the embankment. 2. The soils in and immediately adjacent to the left side of the dense grass were wet and showed signs of sustained seepage. In addition, an area about 15-ft wide that indicated increase moisture content over the adjacent aeeas extended across the face of the embankment from just right of the wet area to the left abutment. Signs of at least surficial movement were apparent in the 15-ft wide strip as well as in areas above and below the strip. 4. A small void was observed in the scarp just left of the grassy area. A small amount of embankment borrow material was present on the surface azound the void. It was not obvious whether this material had been piped to the surface from uncontrolled seepage or eroded from the scarp trace. The Homesrnke Mining Company -5- The Glasgow Engineering Croup, lnc.