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spoils data shows very low SAR levels ranging from 0.1 to 7.9 with a mean value of 0.7. Therefore, due to the dilution of the small areas high SAR materials with the much greater amounts of low level SAP, materials during excavation and regrading no significant SAR problems are expected. V. Hydrologic Balance: Surface Water (Rules 2.04.5, 2.04.7, 2.05.3(4 The Division has reviewed Sections 2.7, 4.8 and Appendices P and Q of the permit application for compliance. Sediment Ponds and Water Rights The sediment control system for the mine is found in Appendix 0 of the application. A11 runoff from disturbed areas at the Trapper mine is muted through one or more sediment ponds. A11 the larger disturbed areas except for Coyote drainage are treated by sediment ponds in series. All ponds are designed to treat the 10-year, 24-hour storm event for the applicable settleable solids effluent limit. All final effluent points have NPDES discharge permits issued by the Colorado Department of Health. Pond sizing was determined by the use of the University of Kentucky's computer model - SEDIMOT II which predicts compliance for the pond under a 10-year, 24-hour runoff and given land condition with the settleable solids effluent limits imposed by the NPDES permit. The model is predicting excessively high total suspended solids for the effluent. However, from actual on-site sampling both by the Division and by Trapper Mining, it is documented that the pond designs are adequate to meet both settleable solids and total suspended solids when applicable. Water rights have been obtained to cover both storage and evaporative losses resulting from the sediment ponds on site. Small Area Exemptions A small area exemption from constructing sediment ponds has been granted to Trapper Mine (See TR-33, June 15, 1981). The Division has granted this small area exemption due to the limited size of the area and due to the fact that ponds or treatment facilities are not necessary for the drainage to meet the effluent limitations of 4.05.2 and the applicable State and Federal water quality requirements for downstream receiving streams. Monitoring The monitoring sites are given in Tables 4.8-8b and 4.8-11a of the permit application. The parameters to be monitored are shown on Table 4.8-12a. The above sections are all in compliance with the regulations. VI. Hydrologic Balance: Ground Water (Rules 2.04.5, 2.04.7, 2.05.3(4 a~ The Division has reviewed Sections 2.7, 4.2, 4.3, 4.8, and Appendix N for compliance with the requirements of this section. -15-