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17. Insufficient design information was submitted for proposed Stock Ponds T-25, T-26, and T-27. The design, construction, and maintenance of all impoundments shall be in compliance with Rule 4.05.9. The Division will require a certified design for each proposed stock pond and a stock pond stability analysis. The certified design should at a minimum include the following information: a spillway cross-sectional profile, an embankment and pond cross-section profile (with side slope information), plan view drawing, and astage/capacity table. Please provide certified stock pond designs for T- 25, T-26, and T-27. Please revise the SEDCAD demonstration to include for each stock pond a detailed discharge table showing the spillway elevation and peak stage elevation to demonstrete compliance wkh 4.05.917)(d). 2.05.4(2)(e) Revegetation Plan 18. SCC has a comprehensive Weed Management Plan covering the three mine permit areas, as required by the Routt County Weed Control District. The county plan is somewhat more detailed than the currently approved plan in Tab 22 of the Seneca II-W permit application package. The comprehensive plan required by the county includes additional weed species of concern, and certain additional control and prevention measures, chemical products, application rates and product labels, and monitoring and reporting requirements. In order to eliminate possible confusion or ambiguity, please incorporate the comprehensive Weed Management Plan into the DMG permit, as an appendix to Tab 22, with reference to the plan in the Tab 22 text, and remove the current weed control narrative on pages 31 through 32b. 19. A severe noxious weed infestation has developed in recently seeded portions of the "D" Pit area, dominated by black henbane and Canada thistle, with bull thistle and houndstongue also present. Due to the severity of the infestation and the minimal presence of desirable vegetation, it appears that complete renovation of the subject area will be necessary, including control of noxious species and reseeding with desirable vegetation. A major portion of the infestation area is within a large concentrated shrub establishment area on the final highwall graded slope. In retrospect, this site may not have been a good site for a shrub establishment area, given the steep south exposure, use of long-term stockpiled topsoil, and presence of noxious weeds in the close vicinity. Due to the need for rapid establishment of desirable vegetation that will be more competitive with the noxious species, it is recommended that Seedmix 1 be used in the renovation seeding of this area. A similar steep, south facing slope was recently seeded with Seedmix 6 in the "B" Pit area. Weed patches are less extensive and there is apparently no black henbane in this area, but control measures will be required and reseeding of portions of the area may be necessary. Broadcast seeding of the entire south facing steep slope area of the "B" pit reclaimed in 2004, with Seedmix 1, may be appropriate, in order to establish perennial grasses that will be competitive with the invasive weeds. Please submit revegetation plan amendments to address renovation of the severe weed infestation on the steep, south facing "D" Pit slopes, as well as the less severe weed infestation on the "B" Pit slopes, reclaimed in 2004.