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accomplished by informal observation and reporting networks in addition to formal monitoring techniques. The Project Skywater FES states: II In research studies aimed at identifying avalanche triggering effects, the effect of relatively small incremental increases in snowfall have been masked by the more pronounced influences of wind, temperature, rate of snowfall, etc." [2, pp. 3-30J A 1977 analysis by Howell states: "The relation between snowpack augmentation and avalanche hazard is greatly compl icated by other factors affecting the release of avalanches and affecting the prediction, warning, and application of countermeasures that mitigate this hazard. In chutes where they seldom run, avalanches occur under rare conditions of recognizably high avalanche danger, when cloud seeding would be suspended under accepted procedures. In areas of hi gh av a 1 anche frequency, such as many chutes in the Red Mountain Pass of the Sa.n Juan Mountains, many avalanches run during nearly every major storm, and successful forecast and warning procedures have been developed, at least partially under the spur of prospective precipitation management. The occurrence of delayed avalanches, after the storm has passed, is rel ated partly to the aU~lmented part of the snow load and mostly to features of snow stratigraphy and metamorphosis not affected by prec i pitat ion management. To the extent that preci pitat i on management focuses attention on avalanche warnings and counter- measures, it will tend to reduce, not increase the hazard." [13, pp. 494-495J Water and Power will continue its cooperative work with the Institute of Arctic and Alpine Research, University of Colorado, and the Forest Service to improve understanding and forecasting of avalanche events. Avalanche conditions are included in the suspension criteria for winter orographic cloud seeding projects, and will be included in suspension criteria for this project. Potential increases in flooding must be considered and avoided in the design of a cloud seeding program. Models will be developed to assess the interaction of snO\'/pack levels, runoff levels, and flood- ing events. A review of the historical record and model calculations will provide information needed to set cutoff levels for cloud seeding when the snowpack reaches a certain IIpercent of normal II (average). Project suspension criteria will be effective automati- cally when the cutoff level is reached to prevent increasing flood hazards in a seeded area. c. Impacts on Plant and Anima.l Communities. - The impacts of snow- pack augmentation on forest vegetation were studied in the San Juan Ecology Project [10J, the Medicine Bow Ecology Project [14J, and the Sierra Ecology Project [15J. In discussing the Medicine Bow Study, the Project Skywater Progr~nmatic Final Environmental Statement states: 13