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Based on the instmmeatation results, Spring is the critical time period far incipient hmdslide movement Activation of slide movement was not attobatabh: m IIling of the reservo¢. The critical time period was idemified as the tip at which maximum snowmelt a~ surface rnooff in the vicinity was occ®g_ If Sre resrrvos was controlled at is below the restriction level d®ng the critical tie period, potential hazard from a dam far7me dne m massive slide movement would be significanfly reduced. However, the limited capacity of the outlet provides a less than satisfactory coturol of reservoir level d®g the cattiest mnoff periods. Fmthe~ore, a massive slide movement could poteatiafly block or damage Ste eaisting ouSd beyond ase_ Based on the observed slow rate of movement; a sadden, massive movement is less Rely, bat continued strain mould poterrtially open a sack that could lead tu a piping faifrse ofthe embankment 1994 WiSr near normal r~off flow, the oullet was capable of maintaimnn the reservos at the restriction level until the critical period for slide movement ended. Dining the critical time period, slide movement prog[essed another 0.4 inches from the previous year Movement progressed m the point where inclinometer ING3 could no longer be measured. Afler the raitical period, the reservos was allowed m fill under strict monimring provisions. The reservoir was above the restriction far a total of about 9 weeks. Piezometdc levels in the embankment and drain flows showed m ab~rmalities relative m hismric trends. Bearings from the renaming two inclinometers obtained at the end of October showed between 0.0 and 0.03 inches additional movement occuaed for the time period the reservoir operated above the rrstrictioa 1995 E~dremely heavy snowpack was repor6ed for all mouWain regions of Colorado prior m the mnoffperiod. Peak nmoff flow for ibe drainage area above the reservoir, however, was less severe than expected. Snow Ali was managed by the onilet, tot heavy rams coincident with rtumffraised the reservo's 5 feet above the restriction for • a 2 week period at the end of May, Inclinometer readings were indicating reactivated slide movemert At the tip of this writing, nmvement had progressed an additional 0.1 inches. Spain raters were also since the first reading of Ste year in ApnZ The sexand reading, in May, of inclinometer ING2 indicated ffiarly 2 inches of movement since the previous. This nmrsuaIIy Lnge movement compared m only 03 inches for inclinometer INGl, was disco~ted because of difficulty in obtaimDg the meastsement The inclmomemr probe, eventually oould ~ 1®Ser be inserhed down ~ casbgg. htclinometer resnlfs indicate fi~lmo of the reservoir shonldbe delayed. The Mommrent Dam case study shows that instu~emafion can be aced as an e11'ective investigative and performance monitotmg mot In the case of Monument Dam, instiume~tion enabkxf nraxi~rm beneficial use of the reservoir without comp¢omising public safety The fsst step inward understanding the complexity of the problem was careful sampling and Iogging of hole bmingsy with particular atteWioa m shear features. The logs provided social info>mation slide history and geometry. Inclinometers instaIled in the bore holes were key m further understanding the slide. The inclinometers eenbled measm~ of strain magnitude amt direction, detemrinatioa of strain rate, and frequency of significant movement Fruthtmrine, the inshame~tion resnNs stowed that movement of 11>e slide was not ceased by lealmge from the reservoir. The mechanism racing slide movement was date®ed m be a remit of increased pore presstses in the sheer zone caused by;n5lhation of water from melting snow on the surface of the slide. The most critical time period for eapecled slide movement is during the S~riog nmoff period. A major limitation of an inclinometer is the finite life expectancy. Movement of the slide has now progressed to a point beyond which further measurements of two inclinometers is ao longer possrble. Installation of larger