Obvious settlement Watch Look for bulges on slope or changes in None Size, location of the crest of the crest alignment. Settlement embankment, especially adjacent to concrete structures. Settlement of crest of Watch Initiate 24-hour surveillance. Mobilize all Sandbags, Size, location embankment that is available resources for repair operations to dozer, shovels, progressing, especially increase freeboard. Fill and stockpile source of adjacent to concrete sandbags. Identify any boils near settlement earthfill structures or if any points for flowing material and pursue corresponding seepage action for boils. is present. Settlement of crest of Possible failure Continue monitoring and remedial actions as Sandbags, Size, location embankment that is described above. Use sandbags to increase shovels, dozer, rapidly progressing the freeboard on the dam if necessary. source of especially adjacent to earthfill concrete structures or if any corresponding seepage is flowing muddy water or increasing flow. Progressing settlement Imminent Downstream evacuation. Utilize all available Dozer, shovels, Size, location that is expected to failure equipment and personnel to build up the crest source of degrade the in the area that is settling. Identify any boils earthfill, embankment to near settlement points for flowing material sandbags reservoir level. and pursue action for boils. Cracks in the Watch Walk on entire crest and slope and check for Stakes, tape Size, location embankment crest additional cracking. measure Cracking or on slopes. Numerous cracks in Watch Initiate 24-hour surveillance. Carefully monitor Stakes, tape Size, location crest that are enlarging, and measure cracking to determine the speed measure, especially those and extent of the problem. Mobilize to fill dozer, shovels, perpendicular to the cracks. Cracks parallel to the centerline source of centerline of the dam. indicate a slide. Follow remedial action earthfill for slides. Large cracks in the Possible failure Continue monitoring and remedial action Dozer, shovels, Size, location crest that are rapidly as described above. source of enlarging, especially earthfill those perpendicular to the centerline of the dam. Cracking that extends Imminent Downstream evacuation. Continue remedial Dozer, shovels, Size, location to pool elevation. failure actions as described above. source of earthfill 5 Equipment, General Specific Material and Data to Observation Observation Condition Emergency Action Supplies Record
Settlement Obvious settlement of the crest of the embankment, especially adjacent to concrete structures. Watch Look for bulges on slope or changes in crest alignment. None Size, location Settlement of crest of embankment that is progressing, especially adjacent to concrete structures or if any corresponding seepage is present. Watch Initiate 24-hour surveillance. Mobilize all available resources for repair operations to increase freeboard. Fill and stockpile sandbags. Identify any boils near settlement points for flowing material and pursue action for boils. Sandbags, dozer, shovels, source of earthfill Size, location Settlement of crest of embankment that is rapidly progressing especially adjacent to concrete structures or if any corresponding seepage is flowing muddy water or increasing flow. Possible failure Continue monitoring and remedial actions as described above. Use sandbags to increase the freeboard on the dam if necessary. Sandbags, shovels, dozer, source of earthfill Size, location Progressing settlement that is expected to degrade the embankment to reservoir level. Imminent failure Downstream evacuation. Utilize all available equipment and personnel to build up the crest in the area that is settling. Identify any boils near settlement points for flowing material and pursue action for boils. Dozer, shovels, source of earthfill, sandbags Size, location Cracking Cracks in the embankment crest or on slopes. Watch Walk on entire crest and slope and check for additional cracking. Stakes, tape measure Size, location Numerous cracks in crest that are enlarging, especially those perpendicular to the centerline of the dam. Watch Initiate 24-hour surveillance. Carefully monitor and measure cracking to determine the speed and extent of the problem. Mobilize to fill cracks. Cracks parallel to the centerline indicate a slide. Follow remedial action for slides. Stakes, tape measure, dozer, shovels, source of earthfill Size, location Large cracks in the crest that are rapidly enlarging, especially those perpendicular to the centerline of the dam. Possible failure Continue monitoring and remedial action as described above. Dozer, shovels, source of earthfill Size, location Cracking that extends to pool elevation. Imminent failure Downstream evacuation. Continue remedial actions as described above. Dozer, shovels, source of earthfill Size, location 5 General Observation Specific Observation Condition Emergency Action Equipment, Material and Supplies Data to Record
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