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<br />program to be conducted in the Upper Colorado Rivcr Basin which was identitied by the <br />acronym CREST (Colorado River Enhanced Snowpack Test). The criteria used to identify <br />potcntial target arcas were as follO\vs: I) a 9000 root elevation base threshold 2) the potential <br />mountain barrier must have at least 5km (-3 statute miles) east-\vest extent and 3) the potcntial <br />mountain barrier has to be located largely or wholly outside designated wildcrncss and National <br />Park areas. Thcse criteria \verc somewhat more rcstrictivc than those used in the two earlier <br />Reclamation reports. Tablc 2 (also from Huntcr et al. 2005) identifies the potential new areas in <br />Figure 2 according to the numbering scheme used in this figure. The \..'est slopes of the Wind <br />River Mountains in Wyoming arc included in Tablc 2 since there is currcntly no secding being <br />conducted in this area. The Wyoming Water Development Commission has. however. awarded a <br />five year contract for seeding in this area. Seeding activities are likely to begin during thc 2006- <br />2007 winter season. The area covered by thosc potential target areas included in Table 2 cover <br />approximately 5.172 squarc milcs. For comparison purposcs. thc existing projects depicted in <br />Tablc I covcr approximatcly 11.688 square miles. <br /> <br />The operational programs being conducted in Utah utilize a lowcr 7000 foot thrcshold to <br />definc the target arcas. This contour level is proposed to dctine the potcntial target arca covering <br />the north slope of the Uinta Mountains, thc Lasal Mountains. the Hcnry l\lountains (called Mt. <br />ElIcn in Hunter ct al. 2005). the east slopes of the Bouldcr ~:Iountains. and thc Abajo Mountains <br />in Utah (numbers 20-23 in Figure 2 and Tablc I). It is also proposed that the 7000 foot contour <br />be used to identify potential target arcas in Arizona. Part ofthc rationalc for inclusion of this <br />lowcr elcvation arca is based upon some earlicr field studies conducted by Reclamation <br />indicating potentially favorable seeding conditions in this area (Super ct al. 1989). Thcse changes <br />would enlarge thc potcntial areas in Utah and Arizona (numbers 26-29) and would also introducc <br />a ncw arca in Arizona: the: wcstcrn end of the lYlogollon Rim area located northeast ofPhocnix. <br />Thcre is another area loeatcd in the extreme upper drainage of the Colorado River located in and <br />near Rocky Mountain National Park that was excluded in the Hunter ct al. 2005 analysis. It is <br />argucd that this area should be considered. so as to include all arcas that provide substantial <br />contributions of strcamtlow to thc Colorado River. There arc a number of on~going wintcr cloud <br />sceding programs being conductcd in the westcrn United States that contain wilderness areas <br />and/or National Parks within the boundarics ofthc intendcd targct areas. <br /> <br />The recommcnded inclusion of lower clevation areas in Arizona would probably require <br />the use of aerial seeding instead of ground based seeding due to warmer temperatures during <br />storm pcriods at thosc latitudes (c.g.. thc etTective Icvcl for silver iodidc secding \..:ill bc at higher <br />elevations \....hich \..ould be more difficult to reach consistently with secding mate-rials relcased <br />from ground gcnerators). eomplicatcd by the fact that ground releases \vould bc made from 100ver <br />e1cvations). This same conclusion was rcached in a Rcclamation report (Super et a!. 1989) that <br />examined the seeding potential of the Mogollon Rim area in Arizona. The following statcment is <br />made in the abstract from this documcnt: "Aircraft sceding would likely bc rcquircd for a largc <br />fraction ofthc Arizona storm clouds:' Thcrc are other new areas in Utah that would potentially <br />bencfit from an aerial seeding approach: 1) the north slope of the Uinta ~Iountains located in <br />northeastern Utah and the laSal. Abajo and I fenf)-. Mountains located in southcastern Utah. The <br />need to consider aerial seeding for the north slopes of the Uintas is driven by the fact that there <br />arc fe\.... rcsidences in the upwind area thal could bc llsed as manual gencrator sites. An option <br />could be thc installation of a network of remotely controllcd. ground gcnerators. The other <br />