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Pitch Reclamation Project -Sediment Control Entbnnkment November, 2002 downstream shell of the embankment about 30-ft back from the toe trace up the right abutment. The . shell extends about 60-ft beyond the drain at the maximum section of the embankment. An outlet pipe extends from the drain to the toe of the embankment and discharges into Indian Creek. The crest of the embankment is about 515 ft long and about 20 ft wide (see Figure 2). The upstream slope of the embankment was designed and constructed at a grade of 3H:1 V. The downstream slope was designed at a grade of 2H:1 V slope. The downstream slope however, was constructed to a 1.85H:1 V grade according to as-built reports prepared by Bingham Engineering and their follow up stability report on the steeper slope. A survey of the downstream slope in line with the wet azea was conducted as part of this current study. This new survey data shows that in the main section of the embankment, the downstream slope measures at 1.66H:1V grade compared to the reported 1.85H:1 V slope. For this study, the slope geometry of the downstream face of the embankment is based on the recent survey data. A survey of the upstream slope was not conducted as part of this study. Slope staking during the remedial work found the upstream slope to about 3H:1 V as designed. A copy of the . survey data is presented in Appendix B. The core of the embankment was founded in a key trench excavated into the foundation material about 8 ft on average along the centerline of the trench. The bottom width of the trench is shown in the original design report to be 15-ft wide with side slopes excavated at 1H:1 V down to the floor of the trench. The downstream side of the core was constructed vertical from the downstream edge of the key trench up to the crest of the embankment. It is 15-ft wide from the crest down to about Etev. 9884 ft. At Elev. 9884 ft the upstream face slopes at a 1H:1 V grade down to the foundation. 3.0 FIELD OBSERVATIONS and EXPLORATION 3.1 General The initial site visit and evaluations of the embankment were conducted in early September 2000 in response to CDWR observation of the seepage on the downstream face of the embankment. The Nomestake Muting Company -4- The Glasgow Eirgineering Group, lnc.