Laserfiche WebLink
DAM NAME: San Luis Tailing Dam DATE OF REPORT: 06 04 19 <br /> TAILING DAM INSPECTION FORM <br /> Directions: Mark an ✓for conditions found and underline words that apply <br /> SEEPAGE AND DRAIN OUTFALL <br /> PROBLEMS NOTED: ❑(30)NONE ❑(31)SATURATED EMBANKMENT AREA ❑(32)SEEPAGE EXITS ON DAM <br /> ❑(33)SEEPAGE EXITS AT POINT SOURCE R(34)MINOR PONDING OF PIPE LEAKAGE AT TOE <br /> DRAIN OUTFALL SEEN: ❑YES M NO ❑(35)FLOW ADJACENT TO DRAIN PIPE ❑(36)DRAIN OUTFLOW TURBID <br /> ❑(37)DRAIN DRY/OBSTRUCTED ❑(38)OTHER: <br /> SHOW LOCATION OF DRAIN ON SKETCH <br /> AND INDICATE AMOUNT AND QUALITY OF SEEPAGE <br /> See Figure 1 for location. Table 1 summarizes toe drain discharge rates over reporting period. Photo 15 shows conditions at <br /> time of inspection: toe drain manifold collection pipe was connected so drainage from pipes could not be observed.Storm- <br /> water runoff sediment accumulation from right groin area continues to be a minor maintenance/access issue in the toe area. <br /> CONDITIONS OBSERVED: ❑GOOD M ACCEPTABLE ❑POOR <br /> STORM WATER MANAGEMENT SYSTEM <br /> PROBLEMS NOTED: ❑(40)NONE ❑(41)NO EMERGENCY SPILLWAY <br /> ❑(42)EROSION AT DROP STRUCTURE ❑(43)CONCRETE DETERIORATED/UNDERMINED ❑(45)STRUCTURE MAY BE TOO SMALL <br /> ❑(46)DIVERSION CHANNEL EROSION ❑(47)INADEQUATE CHANNEL FLOW CAPACITY ❑(48)CHANNEL FLOW OBSTRUCTED <br /> 9(49)OTHER: Photos 9-12 and 17: South Diversion Ditch drop structure replacement project was under construction at the <br /> time of inspection. During construction,storm water from upstream watershed is being contained in the channel by a <br /> cofferdam(berm)constructed across the ditch channel upstream from the structure. <br /> CONDITIONS OBSERVED: R GOOD ❑ACCEPTABLE ❑POOR <br /> MONITORING <br /> EXISTING INSTRUMENTATION FOUND: ❑(50)NONE ❑(51)GAGE ROD IN POOL AREA M_ (52)PIEZOMETERS <br /> ❑(53)SEEPAGE WEIRS/FLUMES ❑(54)SURVEY MONUMENTS M(55)OTHER: Underseepage flows <br /> MONITORING OF INSTRUMENTATION: ❑(56)NO C(57)YES <br /> PERIODIC INSPECTIONS BY: M(58)OWNER ❑(59)ENGINEER <br /> See Figure 2 for piezometer measurements-all instruments remain dry. See Figure 3 for underdrain flow rates;average <br /> underseepage flow rates(measured at outfall pipe)have decreased by about 6 gpm compared to historic(5 previous years) <br /> record,and vary between 31 and 35 gpm over current reporting period. <br /> CONDITIONS OBSERVED: 0 GOOD ❑ACCEPTABLE ❑ POOR <br /> MAINTENANCE AND REPAIRS <br /> PROBLEMS NOTED: ❑(60)NONE ❑(61)ACCESS ROAD NEEDS MAINTENANCE ❑(62)CATTLE DAMAGE <br /> ❑(63)BRUSH ON: UPSTREAM SLOPE/BEACH,CREST,DOWNSTREAM SLOPE,TOE <br /> ❑(64)RODENT ACTIVITY ON: UPSTREAM SLOPE/BEACH,CREST,DOWNSTREAM SLOPE,TOE <br /> Z(65)OTHER: Continue to maintain surface erosion controls(cross berms and rock-lined downspouts)in right d/s groin <br /> repair area,and repair minor gullying adjacent to left abutment groin lined ditch. Consider re-directing surface runoff from <br /> right lower groin away from d/s toe area to prevent deposition of sediment. <br /> CONDITIONS OBSERVED: 9 GOOD ❑ACCEPTABLE ❑ POOR <br /> OVERALL CONDITIONS <br /> Based on this inspection and recent file review,the overall surficial condition is determined to be: <br /> ❑SATISFACTORY Z CONDITIONALLY SATISFACTORY ❑ UNSATISFACTORY <br /> Page 2 of 4 <br />