I n s t r u m e n t s

a n d

M e t h o d s

at Harold's slidepath.An early morning shoot by the Utahdeflection in the sensors.By April the depth of snow in
Department of Transportation producedsmall sluffs on theHarold's was over4 meters.Based on the examination of
southfacingavalanche paths.However,at1145hourssensor #3, this depth of snow renderedthe sensors useless
WhitePine #3 naturallyreleasedandcrossed Highway210.forthe remainder of the winter.The snowpack was hard,
This natural release correspondedto the rapid increaseincold and deep.
creepratesat 1145 hours.Thesnow movementacceleration
for the period between 1145 and 1215 hours was 20.8 cm/
hr.Potentially,thisrapidriseincreepraterelatesto^{4.4 ModificationstoInstrumentation}
2
possiblewidespreadinstabilitywithinthenewsnow^{Forthe winter of 1996-1997a few changeswill be imple-}
during this storm.^{mented to avoid the aforementioned problems.In order to}
prevent the ready rods from bending under the pressure of
4.3 Climatic Effectson Instruments^{creep and glide,angle irons will be welded on the uphill}
side of the ready rods.This should prevent any bendingof
Duringthewinterof1995-1996valuablelessonwerethemountingequipment.Thewiresthatrunfromthe
learned that could lead to more accurate and viable datainstrumentationdownhilltothesensorswillbeburied
collection.Thecreepand glide ofthesnowpackhad aunderground.These alterations will allow the sensorto
profound effect on the ready rods, sensors and wiring.makereadings thatare solelybasedontheangleofthe
In April sensor#3 was excavated and examined.Thesensornot both the ready rod and the sensor.
sensorwasbent atan angle of135degrees fromplumb.Locationofthesensorsisunderreview.The current
Theready rodwas bentatan angle of45degrees.Thesite at Alta provides a good location.However, other sites
snow was gliding around the sensor.Since the sensor wasmay provide better conditions forthe project.A site with
bent beyond 90 degrees, readings on snowpack creep anda shallower snowpack would assure creepand glide read-
glide wereinvalid.The condition of sensor # 3 lead to lowings throughout most of the winter.
confidencein thedatareceivedfrom sensors #1 and2.Also,
apparent was the tensionthat builtup onthe wires that
ran up hill to the datalogger.The tension from the wires^{4.5 Summary}

pulled downhillon sensor #3 and could be a causeof some

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