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The applicant should review the monitoring data yearly and prepare an annual report of the results of the monitoring. The annual report shall compare the monitoring data with baseline data in graphic or tabular form and shall discuss whether this data verifies the applicants statement of probable hydrologic consequences. Because of the need for this information the Division requires the following stipulation: STIPULATION N0. 5 THE PERMITTEE SHALL SUBMIT AN ANNUAL HYDROLOGY REPORT BY JANUARY 30 OF EACH YEAR WHICH PRESENTS AND DISCUSSES THE MONITORING DATA COLLECTED DURING THE PAST YEAR. The Division finds that the operation has been designed to minimize disturbance to the hydrologic balance and prevent material damage. The mining operation is in compliance with the requirements of this section. 4I. Surface Water Hydrology - Rules 2:04.5, 2:04.7; 2.05.3(4}, 2.05.6(3) and Information regarding Surface Water Hydroloyy is found in Section 2.04.5 and 2.04.7 and Appendix K of the permit application. The operation is located in the South Platte River Basin in Weld County. There are many important streams located within Weld county including the Cache La Poudre River, Vrain Creek, Crow Creek, and Kiowa Creek, all of which flow into the South Platte River. However, these streams are distant from the mine site and have not been affected by the operation. Two potentially affected streams are located adjacent to the mine area. Box Elder Creek, an intermittent stream, is located to the west of the mine plan area. The watershed of this stream is located outside the affected area. The ground water within the permit area is not hydraulically connected to this stream. Because of this, the Division has excluded Box Elder Creek from further consideration in this permitting decision. Surface water run-off from the mine plan area would flow to the east to Ennis Draw. Historically, this draw has shown no evidence of surface water flaw. Because the draw is covered 6y 61ow sand, all water flow is subsurface and it can be considered to be an unconfined aquifer. Therefore, impacts to Ennis Draw were considered under the Ground Water discussion in previous section. The applicant has submitted a study on the estimate of run-off expected from the mine permit area (see Appendix K of the application). The estimating procedure used is outlined in section 4, Hydrology of the National Engineering Handbook, U.S.D.A., SCS, 1968. Precipitation data used was from Technical Paper No. 40, U. S. Department of Commerce, 1961 and was verified by the Division using NOAA precipitation data. Curve numbers considered were found to be justified for the site. The results of the study have shown that for a "good hydrologic" condition no, runoff would be generated from a 10-year 24-hour event. This prediction seems reasonable based on the fact that on-site inspections of the mine by the operator and MLRD staff had shown no signs of visible runoff nor any defined runoff channels. The reason for the lack of runoff is the highly permeable mantle of sand that overlies the mine plan area. -13-