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Defective Spillways No (see Riprap across the bed of [he emergency spillway is <br /> Comment) disintegrating. A current analysis [Sediment, Erosion, <br /> Discharge by Computer Aided Design (SEDCAD+)] <br /> suggests that riprap is not required in the emergency <br /> spillway for erosion protection from a 25-year, 24-hour <br /> storm event. There is no evidence of erosion of the <br /> emergency spillway. <br /> Slight deformation (from circular to elliptical) of the <br /> primary spillway tube is evident at the outlet. No <br /> deformation of the protective expanded metal screen <br /> welded to the pipe suggests that the deformation <br /> developed during placement. <br />Dewatering Device No (A The plastic sheet in the bottom of the gate riser noted in <br />Clogged deficiency was 1993 had been removed. Vegetative overgrowth that <br /> corrected at partially blocked the out(all of the principal spillway was <br /> the time of removed. <br /> the <br /> inspection.) <br />Faulty Gates, No <br />Baffles, Pumps <br />Other No <br />Additional Comments: None <br />Maintenance Required: <br />Repair damage to the embankment caused by rodent activity to maintain the integrity of the dam. <br />Repair damage to the upstream face of the embankment caused by water (water line) action. <br />Reseed disturbed areas. <br />Recommendations: <br />With regard to repair of the embankment due to rodent burrow activity, recommend that burrows be <br />uncovered and in-situ backfill be compacted to dam construction specifications. Disturbed areas should <br />be reseeded (unless the area is to be protected by enhanced methods, such as riprap, as discussed below). <br />This maintenance work should be accomplished before the next high water season. At the present degree <br />of burrowing activity, backhoes and mechanical tampers might be required. <br />Rodent control is recommended to eliminate rodent burrowing activity. Recommend that the muskrats <br />be trapped and removed from the site. Recommend the erection of raptor perches. Should burrows <br />continue to be a problem, additional rodent control procedures to halt burrowing activity on the dam will <br />need to be instituted. <br />Erosion of the upstream face of the dam needs to be arrested. Enhanced vegetative efforts might be tried, <br />such as seeding and fertilizing with placement of excelsior mats. However, a more maintenance tree design <br />Canadian Mine Pond # 1, Quarterly Inspection Report and Annual Cenification, 24 October 1994 <br />Page 3 of 5 <br />