Laserfiche WebLink
Sediment Pond Design <br />Pond NHN -002 can be seen on Map 2.05.3(4) -9, along with its associated ditches. Map <br />2.05.3(4) -9 also shows cross sections of the pond design along with design information for the <br />ditches. Pond NHN -002 will be fed by both direct drainage and its two ditches. <br />Discharge from Pond NHN -002 will be controlled via a gated pipe system that has been used <br />with great success at other similar sediment ponds. An 18 -inch diameter pipe with a pair of <br />valved 6 -inch diameter weepholes will be used as the principal spillway. Figure 1 shows an <br />example of the inlet and control valve that will be used. The valve is located at the end of the <br />pipe inlet and is controlled by a wheel on the pond embankment. The pipe inlet, or weephole, is <br />kept open enough to facilitate pit pumping discharge, and can be opened further to facilitate <br />discharge after a storm event. <br />J." <br />18 inch diameter riser , <br />Y <br />{„ W, <br />„t, �•, pipe <br />t `t <br />6 <br />` 6 inch diameter <br />" weephole with kw A <br />valve <br />t <br />r � y <br />.Y+ <br />Figure 1 <br />Example of principal spillway inlet and control valve <br />Both the emergency and principal spillway discharge pipes will be buried for a length of roughly <br />300 feet going north from Pond NHN -002. These pipes will then daylight onto the surface, <br />continue around the knob of the mesa to the east, before turning north and proceeding downhill <br />APPENDIX 2.05.3(4) -8 PAGE - 4 - September 2014 (TR 06) <br />