Laserfiche WebLink
• All runoff waters collecting in Pit 2 will be pumped <br />into a 5.2 acre-foot sediment control pond (No. 4). Although <br />no discharges from this pond are planned, an NPDES permit (NO. <br />CO-0031825), will be secured for this facility. <br />One gauging station currently exists downstream on the North <br />Fork of Bolton Draw. The history of and surface flows recorded by <br />this weir are discussed under the surface water hydrology of Pit 1. <br />In addition to Weir #1 (see Exhibit C-2 for location), diversion <br />records of a ditch right located in the NW; of the NE: of Section <br />11, T8N, R78W give some indication of historic flows at this midpoint <br />in the drainage near the proposed mine. Diversion records for this <br />right are presented in Table II of the Willard Owens report found at <br />the end of this Appendix. <br />Since no gauging equipment was in place on the draw at the <br />time the Willard Owens report was written, these values for flow <br />are just estimates. However, they probably represent with reasonable <br />• accuracy, especially in later years, the spring flow in the Draw. <br />The water rights associated with this diversion is rather junior, <br />and consequently, the ditch is normally shut off after the spring <br />runoff. Flows in the Draw probably decline through the summer and <br />eventually disappear in the fall and winter. <br />Based on the fact that the North Fork of Bolton Draw (watershed <br />IV) drains an area of approximately 1.7 sq. miles, and utilizing <br />the techniques developed by McCain and Janett (1976), Willard Owens <br />Associates estimated flood discharges of this stream at the east <br />boundary of the Pit 1 lease area resulting from various precipitation <br />events. These discharges are presented in Table III of their report. <br />Surface water quality data was collected from two locations <br />in the North Fork of Bolton Draw during May, 1980. One of the <br />sites sampled was Weir ~1 which was installed in that month. The <br />second sample was collected from the culvert where the M&T access <br />• <br />-70- <br />