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ly prepared and will provide adequate support for the embankment fill. All or- <br />ganic matter, topsoil and loose material will be removed and the surface will <br />be scarified. Fill on steep slopes will be keyed into the slope by benching. <br />The D-Portal pond, which has an embankment height greater than 10 feet has been <br />designed to have a minimum factor of safety of 1.8 under all loading conditions <br />(see Illustration 18 of the permit application). <br />Registered Engineer Design and Inspection of Temporary Impoundments <br />All sedimentation ponds and embankments have been designed by a professional <br />engineer registered in the State of Colorado. The applicant has indicated that <br />plans for the D-Portal sedimentation pond will be submitted to the Office of <br />the State Engineer of Colorado when the geotechnical investigation and final <br />design is complete (page V-8 of the permit application). Although the appli- <br />cant has stated on page IV-74 of the permit application that all sediment ponds <br />will be inspected regularly, no inspection schedule or list of inspection para- <br />meters was submitted. The applicant must comply with the inspection reguire- <br />ments for the State Engineer__for_the..D-Portal pond. The Refuse Disposal area <br />ponds must be examined in accordance with section 4.05.9(8) of the Colorado <br />Permanent Regulatory Program and the reports submitted quarterly to the Golora- <br />. do Mined Land Reclamation Division. (See "Stipulations" in this section of the <br />TEA). <br />Stabilization of the Sedimentation Ponds <br />All bare areas created during construction of the sediment ponds will be mulch- <br />ed and seeded (See Map 78 of the permit application). During the final design <br />phase of each dam, a soils analysis will be made of the fill material to deter- <br />mine its erosion potential. The proposed foundation materials have already <br />been classified by the SCS as silty clay loams having low strengths and prone <br />to erosion and piping (page V~9 of the permit application). If final analysis <br />deems it necessary, toe drains or liners will be provided. The D-Portal pond <br />will have both a toe drain and a liner. The entire pond will be covered with a <br />liner consisting of a one-foot thick layer of cohesive material overlain with <br />six inches of compacted gravel. The face of the dam will also be covered with <br />gravel (page Y-19 of the permit application). The applicant has stated gener- <br />24 <br />