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EF&ME1 <br />State.co.us Executive Branch Mail - Re: Diversion ditch design <br />Susan, <br />My original message provides the introduction. <br />have saved the survey results at M: \Coal \LDS \New Elk \RDA, together with exhibit 30 (which shows the <br />RDA design) and section 2.05 of the permit. <br />Once I received the survey results I expected to quickly find the approved design in the permit and <br />compare the two... hmmmm, not so far. <br />Ponds, impoundments and diversions are discussed from page 2.05 -9 of the permit (p21 of the pdf file). <br />There is no specific mention of the upland diversion above the RDA. Also, the ditch is not included in table <br />20 (ditch data). There is a statement on page 2.05 -9: <br />"These sedimentation ponds and associated diversion ditches have been designed according to <br />Section 4.05.6 of the DRMS Regulations. In addition, the diversion structures have been designed <br />utilizing the requirements of 4.05.3 and 4.05.4" <br />Those sections of the regulations do not seem particularly specific or helpful. <br />So my first group of questions is about the design of upland diversions - are they generic? should they be <br />based on some modeling results? should we have any sort of as -built certification? is this permit deficient, <br />or am I missing something? <br />I'll be out tomorrow, and it looks as though you plan to be out this week too. Perhaps we could talk about <br />it when you return. <br />Leigh <br />Leigh Simmons <br />Environmental Protection Specialist <br />Colorado Division of Reclamation, Mining and Safety <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 <br />303 866 3567 (8121) <br />On Mon, Nov4, 2013 at 9:55 AM, Brown - DNR, Sandy <sandy.brown@state.co. us> wrote: <br />Hi Leigh, <br />I'd like Susan to help you out with this <br />review? <br />Thanks, <br />Sandy <br />Will you please provide her the information you want her to <br />On Thu, Oct 31, 2013 at 11:40 AM, Simmons - DNR, Leigh <1eigh.simmons@state.co.us> wrote: <br />Sandy, <br />At the New Elk mine the Refuse Disposal Area fills a steep drainage. Immediately below the RDA is <br />a sediment pond and below that is Highway 12, then the Purgatoire River. <br />Above the RDA is a diversion ditch. <br />Since I have been visiting the mine I have been convinced that the diversion ditch does not have a <br />positive drainage gradient at all points, and have raised this concern numerous times. During an <br />inspection in the summer of 2013 (July, I think), I noticed that the ditch had breached following a <br />storm that was smaller than a 10 year /24 hour event. <br />As part of the abatement for NOV 008 we required that NECC: <br />• clear the ditch of fallen rocks and trees; <br />hftps: / /mai l.g oog le.conVmai 1 /u /0 / ?ui =2 &i Ire29129fcb5 &�iev�-- pt &search =i nbox&th= 14524a4b6f3df26a &si ml= 14524a4b6f3df26a 2/4 <br />