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2.2 Test Pits Tests pits were excavated around the inner perimeter of the Treiber A at approximately 100 to 200 foot spacing as a component of the reclamation slope designs. The test pits were excavated about halfway up the slopes and extended into native sand and gravel and occasionally deeper to the top of bedrock. Although most of the materials excavated and tested from the test pits will not be encountered during tunnel construction, the slope liner materials and geometry may impact shaft construction and should be considered when developing shoring designs. Laboratory test results from the test pits are summarized in Table 2. Complete lab testing results are included in Appendix B. Table 2: Test Results from Treiber A Test Pit Samples Approx Gradation Atterberg Limits Test Depth Gravel Sand Fines Liquid Plasticity Unified Soil Soil Area Pit (ft) N (%) (%) Limit Index Classification Unit TP1 5 4 44 52 27 11 CL Clayey Fill Zone 2 TP8 8 36 56 8 NL NP SW-SM Pit Run TP16 5 18 70 12 NL NP SW-SM Clayey Fill TP19 1 23 60 17 29 15 SC Clayey Fill Zone 1 Clayey TP26 5 55 31 14 30 13 GC Fill Zone 3 TP33 4 12 43 45 27 9 SC Clayey Fill 2.3 Topographic Survey Topographic information within Overland Ponds Pond 1 was obtained by Civil Arts in 2011. An as-built topographic survey within Overland Ponds Pond 2 was performed by King Surveyors, Inc., in November, 2013. A topographic survey inside the Treiber A slurry wall footprint was conducted by King Surveyors, Inc. in June 2014 to establish existing conditions within the reservoir to assist in reclamation slope design. The existing conditions within Treiber A during interconnect construction is anticipated to be as shown on the interconnect design drawings. Topographic surveys of Overland Ponds Pond 1, Overland Ponds Pond 3, and Treiber B were not provided to GEI or have not been performed. Overland Ponds Pond 3 surveying is scheduled for October 2014. G E 1 M Field Investigations 1 7