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3.1.3 Initial Detailed Inspection Report <br />An initial Detailed Inspection Report will be prepared. A preliminary outline for the Detailed <br />Inspection Report is provided as Figure 1. Section 1 of the report will summarize the basic <br />project information, citing the Project Data Report as appropriate for more detailed information <br />on project design and construction. The Project Data Report may be attached as an appendix to <br />the Detailed Inspection Report. <br />Section 2 of the Detailed Inspection Report will document the findings of the initial dam safety <br />inspection, including visual observations and any noted deficiencies from the field inspection. <br />The results of the visual inspection will be described for each major feature of the facility as <br />listed on the outline (Figure 1). The tailing facility inspection form and inspection photos will be <br />provided as appendices to facilitate the visual inspection discussion. The inspection will <br />document the following types of observations: <br />• Visual observations of deficient conditions such as surface erosion, slumps, cracks, <br />settlement, major woody vegetation growth, rodent burrowing or other detrimental <br />conditions on the dam embankment; <br />• Visual observations of the condition of the seepage collection systems at the downstream <br />toe of the dam; <br />• Approximate length of the beach slope in front of the dam to the existing pond; <br />• Estimated size (area) of the existing pond; <br />• Visual observations of the condition of the main storm -water diversion channel and drop <br />structure on the south side of the facility; <br />• General condition of the impoundment area and contributing watershed; <br />Section 3 of the report will summarize, to the degree possible based on the available data and <br />visual observations, the dam safety inspector's evaluation of structural stability of the tailing <br />dam. The structural evaluation will consider normal operating (static) and earthquake loading <br />conditions. This evaluation will consider the previous design criteria, assumptions, and slope <br />stability and seepage analysis results from design reports; as -built construction records (noting <br />especially any differences from design assumptions); available piezometric and drain outflow <br />monitoring data; and observed current physical condition of the dam based on the site inspection. <br />Section 4 will summarize to the degree possible based on available data and visual observations, <br />the hydraulic capacity of the flood diversion systems. This evaluation will consider both design <br />flood events and extreme events (e.g., Probable Maximum Flood). Evaluation of hydraulic <br />capacity will require review of the original design criteria for the diversion channel system and <br />consideration of the current condition of the diversion channel(s) and drop structure located in <br />the left dam abutment. An understanding of the available flood storage capacity (above normal <br />operating pool volume) within the impoundment area also will be needed to evaluate the <br />capability of the facility to store flood flows in excess of the diversion channel design event. <br />Any additional or supplemental engineering analyses that are performed as part of the inspection <br />process to facilitate these structural geotechnical and hydraulic evaluations will be documented <br />and discussed in Sections 3 and 4 of the report. <br />San Luis Project <br />Tailing Dam Safety Inspection and Reporting Program <br />Page 3 of 10 <br />