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Chandler Martin July 14, 2006 Page 3 • kinematic analysis of bedrock discontinuities to demonstrate that the final slopes will have an adequate factor of safety for the proposed end land use; • discussion of the field and laboratory methodology and results used to determine rock and soil strength characteristics used in the slope stability analyses; • engineering geologic cross-sections for all slopes analyzed for stability showing the critical slope geometry, failure plane(s), and geologic and ground water conditions anticipated to occur in the mine slopes; • engineering calculations to demonstrate the factor of safety for all cut slopes that exceed the critical gradient; • technical recommendations for construction of mine cut slopes to ensure adequate final stability, • engineering analysis of the factor of safety for all fill slopes on the mine site that exceed a gradient of 2H:1 V; • recommendations for cut and fill slope monitoring to evaluate the ` adequacy of the slope stability analyses, including what information should be collected and reported and what level of professional skill and licensing should be required, and how often geotechnical inspections will .. be done and reported. Hydrology and Water Quality ` (Refer to SMARA sections 2772, 2773, CCR sections 3502, 3503,3706, 3710,3712) 5. SMARA establishes performance standards for sediment and erosion control. CCR section 3706(d) requires that erosion and sedimentation be controlled during all phases of mining and reclamation, and includes for performance standards for drainage, diversion structures, and erosion control. CCR section 3503(a)(3) addresses the construction of erosion control facilities. The erosion control plan requirements of SMARA may be met by the SWPPP required by the State Water Resources Control Board. OMR recommends that a copy of the SWPPP be appended to the reclamation plan if the SWPPP will be relied upon for SMARA compliance. 6. SMARA requires that site-specific sediment and erosion control criteria be included in reclamation plans. The erosion control methods described in the _ reclamation plan lack the specific details required in a site-specific sediment erosion control plan. Also, the reclamation plan needs to address performance criteria for erosion control as required in CCR section 3706 (d). Performance criteria are necessary in order to identify how much erosion can be tolerated in reclaimed areas before implementing erosion control treatments. Such criteria may state, for example: `Erosion of rills greater in cross section than 5 square inches and exceeding 5 feet in length will be arrested by placement of graded rock interceptors or straw bales to slow concentrated runoff within 1 week following any rainfall event." OMR recommends that an evaluation of the