Laserfiche WebLink
• <br />However, consistent with best manage.~ent practices, if the acce55 system <br />is properly designed, laid out, and drained, the intercepted o-rater should <br />be distributed back over the basin surface and allowed t0 re-infiltrate <br />into the soil mantle if storage is available. -his minimizes the impact <br />on the hydrograph to the point where the true effect of the access <br />system per se, is questionable and certainly beyond ±he state-of-the-art <br />to predict as part of this exercise. <br />The most significant impact that mining activities can have on storm <br />flo:r is through their modification of antecedent storage. As the <br />intensity of disturbance increases, the deficit or storage capacity at <br />any point in time, decreases. With less storage capacity, more cf the <br />precipitation appears as stormflow. <br />There are many techniques for estimating storm runoff. For the <br /> <br />purceses of this retort, one technique has been used, not because it is <br />necessarily the best, but because it is universal in application. The <br />"SCS method" is one of the more widely used techniques and principles <br />of the method are sum.narized here since: (T) it is applicable to <br />unpaged aratersheds, ~•rhere at best, rainfall data are available on a <br />daily basis from nan-recording gages, and (2) it is a standard and <br />recognized engineering approach for predicting storm runoff (U.S. Soil <br />Conservation Service, 1972). <br /> <br />It should be emphasized that if the method is used to determine <br />hydrologic impacts from mining activities, care should be taken to <br />relate the rainfall/runoff relationships to processes insofar as possible. <br />~J <br />