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,/r ,, n.,....i ,. • _~_ according to the guidelines provided by the Division. The samples have met all the effluent standards set forth in Rule 4.05.1. None of the water quality parameters sampled have been found to be at levels which pose a hazard to the environment. Samples taken from the Nu-Mine discharge have consistently had less than 700 milligrams per liter total dissolved solids and a neutral pH. Thus, all indications are that the water quality is good. Specific information about the water quality can be found in Exhibit 4. The application is in compliance with the requirements addressed in this section. VI. Rules 2.04.5, 2.04.7, 2.05.3(4), 2.05.6(3) and 4.05 - Surface Water Hydrology Information on the surface water hydrology can be found on pages 7,8,9, and Exhibit 7 of the application. Information on sediment control can be found in Exhibit 8. There are no streams, springs, wells, or irrigation ditches within a one- mile radius of the permit area. There are two stock ponds within a mile . of the permit area that catch water after major precipitation events. The water flowing from the Nu-Mine edit is tt~e only consistent surface flow in the area. AI2 surface water from the disturbed area passes through a sediment control system. Water from undisturbed areas is routed around the disturbed area by two diversion ditches. She sediment control system at the mine site consists of two interception ditches and a sediment pond with a capacity of one acre-foot. The sediment control system drains 8.4 acres, of which 2.3 acres are disturbed by the mining operation. The sediment pond is designed to contain the runoff from a 10-year, 29-hour storm. The pond is eyuipped with a dewatering device which allows for 24 hours retention time. The emergency spillway will pass the 25-year, 24-hour storm while maintaining one foot of freeboard. A11 the diversion and interception ditches will pass the 10-year, 29-hour storm while maintaining 0.3 feet of freeboard. These structures were found to be in compliance with the appropriate requirements of Rule 4.05. In the event of a discharge from the sediment pond, water would flow through a vegetated Swale into Ohio Creek two miles away. Water flowing down this Swale should cause little erosion because of dense vegetation and moderately permeable soils. The effects of pond discharge on water quality are not quantifiable at the present time because there has been no discharge from the pond. ^owever, the average computed discharge from the 10-year, 24- hour storm is small at 0.4 cfs in comparison to tl~e IG-year average flow of 89 cfs measured at a USGS gauging station on Ohio Creek. Also, since the discharge point is almost two miles from Ohio Creek, mast, if not a11, of the water would infiltrate before it reached Ohio Creek. Therefore, any adverse affects from sediment pond discharge should be negligible. The application is in compliance with the requirements addressed in this section.