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October 19, 2012 C-1996-084/Lorencito Canyon Mine LDS <br /> HYDROLOGIC BALANCE -Rule 4.05: <br /> Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5, 4.05.6; Discharge Structures 4.05.7, <br /> 4.05.10; Diversions 4.05.4; Effluent Limits 4.05.2; Ground Water Monitoring 4.05.13; Surface Water <br /> Monitoring 4.05.13; Drainage—Acid and Toxic Materials 4.05.8; Impoundments 4.05.6, 4.05.9; Stream <br /> Buffer Zones 4.05.18. <br /> • Pond 9/9b was dry. The embankment,primary discharge and spillway were all sound. According to Ron <br /> the pond has not discharged for at least 3 years. An erosional gully had formed on the left side (west)of <br /> the spillway,which will need to be repaired(see photos 1-3). The silt fence,protecting the undisturbed <br /> area from runoff from the road should also be restored. Armoring in the ditch draining the slope above <br /> pond 9/9b needs some repair(see photos 1 &4),the ditch could be widened to reduce the steepness of the <br /> sides. The steep north facing slope above pond 9/9b had fairly sparse vegetation following several dry <br /> years,making the slope vulnerable to erosion(see photos 5-6). Some gully repair is needed here, as at <br /> several locations around the site —limited reseeding may be performed as part of this gully repair process <br /> without resetting the clock with respect to vegetative success criteria for bond release. <br /> • Several years previously a diversion had been created higher in the watershed to reduce the flow to pond <br /> 9/9b, and send more water to pond 9a(see photo 7). Pond 9a was holding a little water,but was well <br /> below the discharge level, (see photo 8). The armoring in the drainage on the eastern side of fill 9a had <br /> been eroded in places and will need to be restored to limit further damage (see photo 9). On the west side <br /> of fill 9a the channel had been altered to improve the flow during large rain events and reduce the potential <br /> for ditch breaches, (see photo 10). The spillway from pond 9a was sound. <br /> • Pond 7 was holding sufficient water to host a flock of ducks,but was well below the discharge level, (see <br /> photo 11). Above the west side of pond 7,near the bottom of fill 7,was a gully which will need to be <br /> monitored, (see photo 12); if access to this gully were easier,repair would be encouraged,but it is not <br /> clear that it could be accomplished without creating a larger disturbance. Since the gullies in this area <br /> appear to contain growing vegetation,there is a chance that erosion will be controlled without further <br /> intervention. <br /> • There are several rills and one more significant gully on the slopes where fill 6 would have been(see <br /> photo 13). These areas should be repaired,possibly from the road above. Long distance hydro-mulching <br /> could be a good option to avoid creating further disturbance. Erosion on the spillway of pond 6 needs to be <br /> filled,possibly with pond sediment, and protected with a line of straw bales. Pond 6 was holding a little <br /> water,but well below the discharge level. Sediment traps above pond 6 were effective,but require some <br /> straw bale maintenance. <br /> • The topsoil borrow area SAE requires some straw bale maintenance. <br /> • The outlet of the culverts to the north of the reference area were partially caved in and need repair, (see <br /> photo 14) <br /> • Pond 5 was muddy. All culverts under the road were sound. The drainage could be a candidate for bond <br /> release, although a small SAE may be needed at the top of the drainage. <br /> • Pond 8 was sound(see photo 15). Most of the water that would drain to it was held in smaller gas well <br /> ponds higher up the drainage. The first culvert under the road to pond 8 needs to be cleaned. The second <br /> and third culverts were fine. These culverts, and their owners, should be identified on the map(s) <br /> generated as part of the permit renewal process. There was a very steep ditch above the road to pond 8 <br /> Number of Partial Inspection this Fiscal Year: 3 <br /> Number of Complete Inspections this Fiscal Year: 2 <br /> Page 3 of 11 <br />