Laserfiche WebLink
c <br /> <br />no longer be needed to retain runoff. ,fit this point, <br />the runoff from the reclaimed surface will drain unrestricted into the <br />receiving streams. <br />Estimated increase of flow in receiving streams. Based upon 35e increase <br />in runoff from disturbed sites. <br />Recei ving Streams Percent Yield Increases <br />Bolton Draw 2.7a <br />Bush Draw 0.30 <br />Williams Draw 1.20 <br />Sudduth Draw 0.4a <br />These seem to represent a worst case condition. Any actual increase <br />would probably be less. <br />The sediment pond effluent limitations on total suspended solids is <br />set at 30 mg/I by fJPDES standards. This affluent limitation will have <br />the effect of reeuirinq Kerr Coal's mining operations to release watei <br />which is actually lower in sediment load than national baseline Levels. <br />This condition may, in turn, have the effect of causing erosion down- <br />stream from the mine plan area to regain the natural level of sediment <br />load. This effect has been suggested on a theoretical basis at several <br />mine sites. However, it has yet to be documented either by the Division's <br />inspectors or by the companies. Should the erosion occur, it would <br />begin immediately downstream from the discharge points from the ponds. <br />Given the infrequent nature of stream flow in this area, it would not <br />spread rapidly, and could be mitigated if it occurs. <br />2 <br />Salt Loadino <br />Sediment and flow control facilities such as sediment ponds and diversion <br />ditches which detain water will have the effect of increasing the concen- <br />tration of total dissolved solids in the water due to evaporation. Also, <br />any water pumped from the pits into surface drainages to facilitate <br />operations may contain relatively high levels of dissolved salts, while <br />difficult to quantify, might increase in streams draining the mine property. <br />Using data from .Williams Draw the applicant has made the following estimate. <br />The average salt discharge of 172.3 grams per day times G2 days _gives an <br />assumed annual salt discharge of 1017 kilograms per year from the mine plan <br />area into Williams Draw. <br />Considering the respective amount of disturbed area tributary to each of <br />Bolton, Bush, Williams, and Sudduth Dra:as, the total amount of salt load- <br />ing on receiving streams is estimated to 6e about 54 kilograms per year. <br />(p 180-12Ghhhhh) <br />This can be broken down into the amount of loading on each individual stream. <br />Bolton Draw <br />Bush Draw <br />Williams Draw <br />Sudduth Draw <br />37. J ;;ilograms/yr. <br />3.2 kg/ur <br />20.7 %47/yr <br />2.7 ~~/yr <br />-R- <br />