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Since the operation will only be active for 6 months per year, the full gold mining operation will take <br />approximately 12-13 years. <br />1.2. Sediment Control SYStem for Gold Operation <br />The permit area is basically divided into 2 areas, the northern azea that drains into Pond A, and the <br />southern area that will drain into newly constructed Ponds #1 and #2. The gold mining operation will <br />control sediment through a number of measures. First, the 8' berm created on the west side of the <br />permit area next to the ROW of Highway 9 will channel all runoff from any disturbed azeas into two <br />sediment ponds located at the southeast corner of the permit azea. This is also the low point of the <br />permit area. Water will enter Pond #1 which will then flow into Pond #2. Pond #1 will serve as the <br />cleanout pond, while Pond #2 will serve to collect runoff from a 100 year event, although much of <br />this flow will be captured in either Pond A (below the prep plant) or the active mining pits. A third <br />pond, Pond #3, will be installed to handle pumped water from the active mining pit. It will then feed <br />Pond #4, which will allow the clean water to seep back into the ground, thus avoiding a dischazge <br />from the site. No runoff from the site will be allowed to enter ponds #3 and #4. <br />The 8' high berm will have a maximum 2.OH:1.OV and will be created from the existing disturbed <br />gravel on the site. Topsoil may also be used to create the berm on the southern portion of the mining <br />azea if excess topsoil is available from stripping. In all cases, gravel and topsoil will not be mixed to <br />create the berm. A ditch of 2.0 feet depth and 2H:1 V sideslopes (Collection Ditch #1) will be con- <br />structed on the west side of the berm to direct all disturbed area flows into Pond #1, then Pond #2. <br />This ditch will cross access roads in two locations as shown on Map C-2, where a 18" culvert will be <br />placed in the ditch for the road crossing. <br />The terrain rises to the east from the permit area, but the Columbia #1 Ditch is located neaz the east <br />permit boundary and this ditch prevents any undisturbed runoff from entering the site. See Map C-2. <br />Sediment Pond #1 is simply a sediment cleanout pond and will not be used for detention volume. <br />Sediment Pond #2 will handle the runoff from the majority of the gold mining azea. Pond A will han- <br />Alma Placer 7/03 14 <br />