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G-11
<br /> conglomerate is limited in areal extent and may not be present at the Project site. The D1 Sequence
<br /> may reach zero thickness in the southwest part of the site(Deschesne,M.,et al;2011).
<br /> According to published geologic mapping,unconsolidated deposits at the site consist of Pleistocene
<br /> Peoria loess and Holocene dunes (Tweto; 1979, and Braddock and Cole; 1978). The loess is
<br /> composed of fine-grained particles of silt and clay and the(eolian)dune sand consists of sand and
<br /> silt.Surficial unconsolidated deposits up to 150 feet thick that included sand and gravel were logged
<br /> in an oil and gas test well in Section 19, T2N, R63W, about one mile south of the site (COGCC;
<br /> 2019).
<br /> Refefnras:
<br /> Braddock,W.A.and Cole,J.C.; 1978;Preliminary Geologic Map of the Greeley 1 degree by 2 degrees Quadrangle,Colorado and
<br /> Wyoming,U.S.Geological Survey Open-File Report 78-532;Scale 1:250,000
<br /> Colorado Oil and Gas Conservation Commission(COGCC);2019;Online Data s://coecc.state.co.us/data html#/coeis
<br /> Kirkham,R.M.;1978;Location Map of Drill Holes Used for Coal Evaluation in the Denver and Cheyenne Basins;Colorado Geological
<br /> Survey,Open-File Report 78-08
<br /> Kirkham,R.M.and Ladwig,L.R.;1979;Coal Resources of the Denver and Cheyenne Basins,Colorado;Colorado Geological Survey
<br /> Resource Series RS-5
<br /> Dechesne,M.,Raynolds,R.G.,Barkmann,P.E.,and Johnson,K.R.;2011;Notes on the Denver Basin Geologic Maps:Bedrock Geology,
<br /> Structure,and lsopach Maps of the Upper Cretaceous to Paleogene Strata between Greeley and Colorado Springs,Colorado;Colorado
<br /> Geological Survey
<br /> Tweto,O.;1979;Geologic Map of Colorado;U.S.Geological Survey Special Map,Scale 1:500,000
<br /> Wray,L.L.and Koenig,N.V.;2001;The Coalbed Methane Potential in the Upper Cretaceous to Early Laramie and Denver Formations,
<br /> Denver Basin,Colorado;Colorado Geological Survey Open-File Report 01-17
<br /> (c) Submit a brief statement or plan showing how water from the de-watering operations or from
<br /> runoff from disturbed areas,piled material, and operating surfaces will be managed to protect
<br /> against pollution of either surface or groundwater(and,where applicable,control pollution in a
<br /> manner that is consistent with water quality discharge permits), both during and after the
<br /> operation.
<br /> Due to the nature of the deposit(eolian sand)and the limited likelihood of encountering free water
<br /> conditions (i.e., rapid releases or significant flowing seeps, etc.), active de-watering is not
<br /> anticipated in conjunction with mining operations.
<br /> To the extent saturated conditions are encountered which may affect mining operations(i.e.,minor
<br /> seeps, saturated zones (e.g., "aquicludes"), or precipitation effects (originating as run-on or
<br /> Keenesburg No. 2 Mine_112 Reclamation Operation—November 22, 2019
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