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-31- The applicant constructed an access road from County Road 92 to the refuse disposal pile under the interim permit approval. That road is approximately 1,275 feet in length, with an average overall grade of 10.1%. The as-built plan, profile and cross-sections contained within the permit application as Figures 2.05.3-3A and 36, depict cut and fill slopes between approximate stations 2+00' and 8+00'. The applicant has supplied insufficient information to allow the Division to determine whether these cut and fill s]opes conform with the operational slope limitations of Rule 4.03.2(3)(c)(i)(d)(viii), or whether the permanent reclaimed configuration conforms with the stability requirements of Rule 4.14.2(1)(b). Further, the applicant has not provided sufficient information to demonstrate that this access road is "suitable for the approved post-mining land use", as required by Rule 4.03.2(7)(a). For this reason, the Division deems it appropriate to impose the following stipulation upon permanent program permit approval. Stipulation No. 9 7HE OPERATOR SHALL POST AND MAINTAIN "STEEP SLOPE CAUTION SIGNS" ALONG THE ACCESS ROAD TO THE REFUSE DUMP. TWO MONTHS PRIOR TO ABANDONMENT AND RECLAMATION OF THE ACCESS ROAD, THE OPERATOR SHALL SUBMIT APPROPRIATE GEOTECHNICAL STABILITY ANALYSIS TO DEMONSTRATE COMPLIANCE WITH THE STABILITY REQUIREMENTS OF RULES 4.03.2(3)(c)(i) or (d)(viii); OR IN THE ALTERNATIVE, THE OPERATOR SHALL SUBMIT A PROPOSED RECLAIMED CONFIGURATION WITH APPROPRIATE STABILITY ANALYSES TO DEMONSTRATE CONFORMANCE WITH THE REQUIREMENTS OF RULE 4.03.2(7). Rule 4.03.2(4)(e)(v) requires the installation of road ditch relief culverts at specific, regular intervals, depending on the grade and length of road. The purpose of the rule is to discharge water from the roadside at frequent enough intervals to prevent ponding on the road. The operator requested a variance from the culvert spacing requirement in Response Volume II, Attachment A, page 3. The operator has designed a large riprap channel to collect road drainage from the entire road length and route it to a stilling basin. Since this design method achieves the same required result, the variance request is hereby granted. The operation is found to be in compliance with the requirements of this section. XVI. Ponds. Impoundments, Diversions - Rules 2.05.3 and 4.05 As a result of surface and underground disturbance at the Dorchester No. 1 Mine, water discharged from the mine would be high in total suspended solids. To mitigate this condition, the operator has designed a sediment control system which will remove suspended solids prior to the water being discharged to the receiving stream. The final water discharged will be able to meet both Federal NPDES discharge requirements, as well as Colorado Department of Health Receiving Stream Standards. The Division was responsible for reviewing the sediment control system from both a design and performance standpoint to ensure that the above standards will be met.