Laserfiche WebLink
<br />' The ditch locations for the heap leach facilities are <br />shown on Figure C-10. Ditch cross-sections for the heap leach <br />facilities are included on Figure C-9. Table D.9-I shows ditch <br />design calculations using Manning's equation. As shown on Table <br />D.9-1, heap leach facility diversion ditch capacities of 313 <br />and 1,587 cubic feet per second (cfs) are more than adequate <br />' to handle the expected design storm flows of 12 and 228 cfs, <br />respectively. <br />The East and West Pit ditch locations are shown on Figure <br />C-13. Ditch designs are shown on Figure D.9-1. <br />Ditches for the waste rock disposal areas have been <br />L designed to collect and control runoff from the waste rock <br />disposal areas to minimize erosion and sediment generation <br />until revegetation is established. No design storm was used <br />in ditch design. Ditch locations are shown on Figure C-13. <br />D.9.2 Sediment Control <br />' Soils in the project area are natura~ly erosive. <br />Drainages are deeply incised and during storm e~~ents erosion <br />1 and sediment generation is evident. Sediment control structures <br />will be installed at the outlet of all ditc~ structures <br />draining directly into the Rito Seco. <br />Sediment control structures will consist of check dams <br />as shown on Figure D.9-2. <br />' Erosion protection/runoff control for the mill site area <br />are part of the detailed mill plans which have not yet been <br />developed. Details of the mill site drainage wild be provided <br />upon completion of the mill design. <br /> <br /> <br />D-61 (Revised 4/20/89) <br />