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Walsenburg Sand and Gravel - Sand Arroyo Pit Page 3 <br />Permit # M- 1978 -283 Technical Revision <br />MINING PLAN CLARIFICATION AND REVISED MAXIMUM DISTURBANCE ALLOWED <br />For lack of a better term we will use word "creek" to define the <br />water flow regions of the ephemeral drainage known as the Sand <br />Arroyo. <br />During the 2002 permitting, the application reduced the maximum <br />disturbed area to five acres more or less, when the DRMS insisted <br />that WSG take responsibility for grading all slopes within the <br />permit area to 3h to lv no mater how they were created. The <br />original intent was to mine within the banks of the creek in such <br />a way that no lateral banks would be affected and whenever water <br />flowed down the creek it would refill the excavated area with <br />sand. In addition, there was a source of dune sand (wind blown) <br />in the northwest corner, outside the banks of the arroyo that had <br />value. This area required mining into a hill side above the <br />creek bottom and outside the water flow area. This area would <br />not be affected by highwater flows down the creek. <br />On the southwest part of the disturbed area there is a section of <br />creek bank that has been mined for a different type of sand. In <br />this area the creek bank was mine leaving a highwall. While <br />there was a cutbank in this area 600 feet of bank has been <br />redisturbed by mining and will be slope. This is an example of <br />the area where it is Walsenburg Sand and Gravel's (WSG) <br />responsibility to grade the bank 3:1 but the probability of it <br />being later eroded due to highwater is very high. <br />The water flow also leaves cutbanks along the sides of the Arroyo <br />that are naturally occurring and are not created by WSG. In <br />2002, the Division Staff requires WSG to commit to grading all <br />the cutbanks to 3:1 no mater the cause. This created a problem <br />such that WSG might never complete reclamation because when <br />highwater flows down the arroyo, some or all of the slopes would <br />be eroded, leaving near vertical cutbanks. WSG would then have <br />to go back and regrade them after nature destroyed the slopes. <br />The proposed change would revise this so that WSG would only <br />grade slopes to 3:1 where they have been disturbed by mining. <br />The newly created slopes would be seeded as soon as practical. <br />Once grading and seeding was done it would be documented with <br />pictures to show the work was done as required. The Division <br />would be provided the proof so that later, if the sloped areas <br />were damaged by highwater then Walsenburg would be relieved from <br />having to reslope and seed them a second time. The naturally <br />occurring cutbanks would be left as is and Walsenburg Sand and <br />Gravel would not be the responsible fixing them. <br />If we limit the amount of bank sloping liability to only the <br />areas mined vertical by Walsenburg, then the area of disturbance <br />can be increased and the bond remains nearly the same. The <br />