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year flood peak was Eound to be 570 cfs, but was rounded to 600 s of use. The 25-year Elood is unlikely to have any major impacts site. The ISiddle Fork of the South Platte River has a well-defi~ valley, and as can be seen on Plate No. lA, the river comes very recirculating pond embankment in one location, but elsewhere is ] distance Erom the pond embankment and other mine activities. The crest is approximately 22 feet above the river at the point where nears the embankment. It is unlikely that river Flooding upstree embankments could result in overbook flow that could find its wa; ponds. In addition, a field survey Eound the toe of the north er embankment to be 8 foot above the river. Cross section AA in P1~ taken at the critical area of the South Platte. Riprap was place of three feet per the Corps of Engineers, then a five foot walkwi with two feet of riprap at the toe of the embankment. Accordingly, the river "threatens" the pond embankment only at t the river and the toe of the embankment are immediately adjacent other. Since our earlier report indicated a flood level of appr feet will occur, the toe of the embankment has been riprapped to of five to six feet above the normal river water elevation to pr embankment in the event of the 25-year Elood. A bench, or Elat included in response to a request from the Corps of Engineers to vegetation and access route alongside the river. This is seen i on Plate No. LA. WASER SUPPLY DITCH The HLRD requested additional information regarding the conveyen Erom the source ditch to the sluice box and pond operations. An corrugated metal pipe serves as the offtake from the source ditc'. existing pipe delivers water to the top of what is known as the ~ Springs Cut in the vicinity of the old wash pond. The Colorado an approximate 100 foot wide "valley". The bottom of this "vall~ dirt road as well as a small meandering waterway. This waterway approximately 1X slope and is the means by which water leaves th pipe and is conveyed to the point at which it is pumped under hi. the Ross box. The area traversed by this waterway is a previous and is primarily gravel and cobbles not subject to erosion. Sho sediment be picked up by this waterway, its ultimate destination recirculating pond where the sediments will settle out. This supply ditch has been used historically as an effective and means of supply. Due to its location, any potential failure of 1 ditch would be captured in the recirculating pond should such an event occur. Fs for ease upon the mine 'd river ;lose to the ~cated some embankment the river 0 of the pond to the i of the to No. lA xas i at a height v followed point where o each imately four n elevation act the ea, has been ravide a section AA of water xisting This lorado rings Cut is " contains a lows at existing pressure to mined area d any s the Efficient e supply 4