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OOlll14 danger, when cloud seeding would be suspended under accepted procedures in areas of high avalanche frequency, such as many chutes in the Red Mountain Pass of the San 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 related part 1 y to the augmented part of the snow load. and mos t 1 y to features of snow stratigraphy and metamorphosis not affected by precipitation management. To the extent that precipitation management focuses attention on avalanche warning and countermeasures, it will tend to reduce, not increase the hazard." [16, pp. 494-495J Reclamation will continue its interest in studies to improve under- standing 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 snowpack levels, runoff levels, and flooding 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 certai n "percent of normal" (average). Project suspension criteria will be effective automatically when the cutoff level is reached to prevent increasing flood hazards in a seeded area. 3. Impacts on plant and animal communities. - The impacts of snowpack augmentation on forest vegetation were studied in the San Juan Ecology Project [14J, the Medicine Bow Ecology Project [18J, and the Sierra Ecology Project [19J. In discussing the Medicine Bow Study, the Project Skywater Programmatic Final Environmental Statement states: "Few circumstances were found where snow accumulation appeared to be a limiting factor in forest ecology. One of these, it was suggested, was at some locations near tree- line where ribbons of forest alternate with glades in which snow accumulates. The depth of snow, and the adverse effect of snow molds on survival of young trees, apparently serve to stabilize the boundaries of the glades. An increase in average wintertime precipitation might lead to an extension of the area where the glade-and-ribbon pattern prevails. On the other hand, in a New Mexico setting, the growth of spruce was found to be uniform in adjacent areas even though the average snowpack differed by a factor of more than eight. "The conc 1 us i on was reached that a hi gher mean snow accumu- lation probably would not affect primary productivity unless the growing season was shortened." [1, pp. 3-111J 17