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"'1 ., 003333 ~K\- l/~V~ Whiskey Creek Landslide / The Whiskey Creek landslide is the largest slide in the/studY area. However, it is also possibly the oldest and probably the least active with exception of the east lobe of the toe where we concentrated our' field and instrumentation efforts, However, major reactivation of even this relatively small active area would cause the most serious consequepces for transport and commerce in the area as it is conceivable that the Interstate highway could be c)osed and in a worst case scenario, the Eagle River yfou1d b~ dammed. , I CvS ~'-l" e-~>> I.4.-C\~ ~ Because of the limited number of EDM point (4) and drill ho1e(s) (1) budgeted to instrument this landslide, I carefully located them to maximize the immediately needed information, The EDM point locations were selected for the following reasons: EDM point lc is located upslope from a relatively small slump landslide that was initiated by the Interstate highway roadcut, This roadcut is so unstable that it presents a constant maintenance problem for CDOH and complete failure of it would at least temporarily close the highway and reduce support for the potentially unstable landslide material above it. EDM point 2c is located about 500 ft upslope from 1c because of the need to monitor any large scale movement upslope from 1c if movement of lc rapidly increases. EDM point 3c was located for the same reasons as lc except it monitors a different slump landslide that is even more threatening. EDM point 4c is located at the same location as the only drill hole and is discussed subsequently,' It should be pointed out that the most immediate problem posed by the Whiskey Creek landslide is that of increased activity of these relatively small active landslides at the lower edge (toe) of the large landslide, These originate in older metastable landslide material and could in, themselves be a costly problem, and accelerated movement of these very likely could be the precursor(s) tO,larger scale movement of the major slide mass. Monitoring of these EDM points did not begin until June 20th and so as is the case with many of the others on the other landslides their real value will not be apparent until next spring, The only drill hole at Whiskey Creek was drilled for two reasons: to determine the thickness and composition of the landslide at one important location and to install an inclinometer at this key location. Although the inclinometer casing was set at 295 ft in Belden Shale bedrock, the casing collapsed during cementing operations rendering it useless, The base of 1ands!ide maJeria1 was found ~t 214 ft.be10w ground level. The landslide material is 'consigerably' di ffE1rent"in compOsi ti on and .textur~;thanthat.maki ng up the other landslides in the area. It consists predominantly of 1;to-6;'in. clasts of mudstone and'sandstone in a clayey matrix, Its texture indicates that the Whiskey Creek landslide initially formed as a massive earthf10w or - 11 -