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The entrance to the emergency spillway is located 4.3 feet above the <br />principal spillway orifice. 'There will be no flow thrcxxltr the emergency <br />spillway channel as a result of the rrmoff fr® a 10-year, 24-hour <br />precipitation event or less. <br />The peak stage fr'an the 100-year, 24-hobs precipitation event is at <br />elevation 7017.3; the top of ~~*+~*+* elevation is 7019.5. This allows <br />for 2.2 feet of freeboard. This is based on worst case, i.e., that the <br />orifice and perforated riser ~ gets plugged arri all flora must go thrrnx~i <br />the emergency spillway. <br />SYmm~- <br />S »++~*+t Porr3 008's sagacity is attributed partially to the enibanlm~ent aryl <br />partially to the porn excavation. D~u~ing passage of the 10-year, 24-hour <br />storm, the spillway does not discharge cFr7imc„t downstream nor is there <br />any flow thrax~r the emergency spillway. The embankment is oonstrucked <br />to be stable and provide adequate freeboard. Therefore, based on the <br />design, this structrse oca~y~lies with the appropriate regulations for a <br />~l~*+tation struchse. Peabody Coal Ccatpany will periodically inspect. <br />this strucGse for sediment storage, strusttsal integrity, and hazardous <br />conditions. Maintenance and ramx9;a~ work will be performed i.r1 accordance <br />with the approved mine permit. <br />Construction Summary <br />In aooardanoe with Rule 4, Part 4.05.6(7) of the 13rles and Regulations of <br />the Colorado Mined Land Reclamation Board (CMLRB) pissuant to the Colorado <br />Surface Coal Minim Reclamation Act 34-33-101 et seq., I, Ronald J. Gehrke, <br />hereby certify that the construction of 4er3;-mea+*ation Pond 008 was <br />inspected and constructed under my supervision. The oonstzuction of Pond <br />008 was supervised on site by Chuck McQrlloh, Operations Fl~gineering <br />Manager at the Seneca II Mine. Chuck assured all work was performed in <br />accordance with the design and the specifications. I inspected the <br />structtse on May 27, 1992 and August 5, 1992 to verify the potd's spillway <br />installation and riprap construction. I inspected the Ford 008 site on <br />August 20, 1992 to verify the as-built oorriitions of the riprapped <br />emergency spillway. I, Ronald J. Gehrke, am a 1977 graduate in civil <br />7-6f-17 Revised 08/24/92 <br />