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21. The Storm Water Management Plan has specified all berms/windrows to be at least 24 inches in <br /> height to contain the design storm event, however the plan lacks specific details on the sediment <br /> pond within the processing area. Please note, Exhibit E Maps do indicate this feature to be 10 <br /> feet deep, but there is no further information regarding the length and width nor capacity. In <br /> accordance with Rule 6.4.21(7)(f)and Rule 6.4.21(10)(a), please update the permit and SWMP <br /> accordingly. <br /> The initial sediment pond is 10'wide x 35'long x 10'deep,giving it a storage capacity of <br /> roughly 25,000 gallons. Once this pond fills with water,a pipe carries storm-water to the lined <br /> sedimentation pond which settles the discharge from the mine.These dimensions and <br /> capacity have been updated in the SWMP and the referenced permit. This secondary <br /> sedimentation pond is a CDPS Permitted feature(CO0038334)and as mandated under Consent <br /> Order IC160803,has a storage capacity of two million gallons and provides additional settling <br /> prior to release into South Mosquito Creek. <br /> 22. As required by Rule 6.4.21(8)(a)locate on a map, in Exhibit E, all tributary water courses, wells, <br /> springs,stock water ponds, reservoirs and ditches, on the affected land and on adjacent lands <br /> where such structures or waters are within two(2)miles, of the existing or proposed affected <br /> lands. The required information may further be limited to that area which can also be <br /> demonstrated by the Operator to lie within the local ground and surface water regimes that <br /> include the affected lands.Additionally, as required by Rule 6.4.21(8)(d), identify and locate on a <br /> map, in Exhibit E, known major fracture systems that affect rock formations under the proposed <br /> affected area. <br /> Please see updated Exh E which includes water and geologic features. <br /> 23. Within Exhibit U, the application materials do not include a demonstration of Rule 6.4.21(17) <br /> regarding plant growth medium. Please revise Exhibit U accordingly. <br /> Please see Exh U which has been updated,consistent with Exhibit D Reclamation Plan. In <br /> short,Applicant will attempt to salvage any soil found within the permit area,test that soil for <br /> TAL metals and compare those results to the Industrial Soil PRGs(EPA,as amended by CDPHE <br /> and CDRMS),and if those soil resources do not exceed the total metal concentrations meeting <br /> the Industrial Soil limits,then further soil testing will be done in accordance with Rule <br /> 6.4.21(17)to demonstrate that the soil is,or after proposed amendments will be,supportive <br /> of re-establishment of vegetation with the seed mix as used by DRMS in the revegetation of <br /> the London Mine Tailings reclamation program(2014). <br /> If the salvaged soil is found to not meet the criteria to support vegetation,then screened fines <br /> from a nearby borrow source will be utilized and amended in a similar manner to the DRMS- <br /> 2014 reclamation program at the London Mine.This program was demonstrated to be <br /> effective at our site over the past 9 years. <br /> The Division will calculate the total required financial warranty for the site after the responses to this <br /> review letter are received.The Division will provide the Applicant a copy of the Division's reclamation <br /> cost estimate for review prior to the decision on the application. <br />