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<br />TaerrB~ ~z~i~e tpc. <br />III IIIIIIIIIIIII III <br />999 <br />July 20, 1998 <br />Mr. John A Ku~ar, District Manager <br />Mme Safety and Health Administration <br />US Department of Labor <br />P.O. Box 25367 <br />Denver, Colorado 80225 <br />Dear Mr. Ku7ar: <br />-~CEIVED <br />r!nv U 5 1998 <br />.; , e ~eoiogp <br />Subject: Trapper Mme, ID No. OS-02838 <br />Coyote Dam, ID No. 1211-Cf)-09-02838-01 <br />Annual Impotmdmem Report; 30 CFR, Section 77.21 art(s) <br />As required by 30 CFR, Section 77.216-4(a), the following is a report for the sediment control struchae, Coyote <br />Dam. The structure is owned and operated by Trappe Mining Inc. and the umstruction of the embml®e~ bas <br />been completed for many years. Its purpose is to control surface nmoff from the surface mining operatioaa at <br />the Trapper Mme. <br />During this reporting Period, no changes were made in the geometry of the impounding structure. All <br />appurtenant structtnes inchrding the trash tack, decant system and emergenry spillway are in place, operating as <br />designed, and being Properly n.a; einrrt No instnmmwtation is aarently regrrired nr pla®ed to be installed, <br />monitored or maimained at this strucMe. <br />A land survey of the impoundment area was performed July 10, 1998 by Trapper's survey new. with the aid of <br />an inflatable raft, the top of sediment was determined W be at El. 6297.0. The minimum, maximum and present <br />depth and elevation of the impotmded water and sediment for this reporting period are as follows: <br />water Sedimem <br />Minimum Depth/Elevatian - 9/16/97 4.90 ftJEl. 6301.9 12 fr /F1, 6297.0 <br />Maximum Depth/Elevafion - 03/26/98 9.60 ftJEL 6306.6 ! 2 tt/El. 6297.0 <br />j Present Depth/Elevabon - 07/14N8 7.50 ft./EI.6304.5 12 R/EL 6297.0 <br />The r®aitm~g storage capacity of the impounding sttuctme, from the a¢tent water surtax (El. 6304.5) to the <br />crest of the emergency spillway (El. 6312), is calculated to be 62 sue-feet. <br />The approximate volume of water and sediment currently impoumded is calcuated to be 38 aao-feet each. <br />The depth and volume of impounded sediment, as reported, are based on information supplied by other <br />professionals from previousannua! certiEed reports. <br />I hereby certify that, to the best of my )mowledge and information, the operation and maintenance of the Coyote <br />Dam was in accordance with the aPProved P~ d~8 this rePo~B Pmt- ...wnnm...._ <br />RaymondG. DuBois, P.E. <br />Senior Project Engitteer <br />Dopy. FV Luke <br />file <br />P.O. Box 187 <br />Craig, Colorado 81628 <br />(970) 824-4401 <br />81416 <br />