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-66- DISCUSSION The Green River will undergo major changes in the next ten years. These changes will affect the entire section of the river within the confines of the study area, Under present conditions, excellent trout habitat exists from the town of LaBarge to the Rig Island Bridge. Bottom fauna present in-this section of the river ranges from moderate to good. The Limiting factor appears to be the relative absence of algal and aquatic plant growth which offer sources of food and attachment. Silt conditions are high during spring run-off, per- iods of April, Asay and part of June. The water velocity, however, is sufficient to prevent an accumulation of silt in the riffle, food producing, areas, Silt carrying waters are normally gone by the latter part of June. After this time, silt is introduced only during extensive rainfall. Chemical analyses, of tests conducted, give no indication that the stream is suffering from a lack or overabundance of any specific chemical or compound. Total dissolved solids show an expected rise at each .successive downstream station. This concentration increase is due to the terrain through .which the river flows, high salt content of surrounding countryside combined with soils F of high drainage texture allow salts to leech from the soil quite readily. This section of the river contains a limited brown trout population. The population of trout is very good considering the small numbers that have been planted, an average of 604 fish per surface acre of stream per year over a twenty-year period, The majority of this area will either be inundated by the Fontenelle Re- servoir of the Seedskadee Project, or have normal stream conditions drastically f changed through water manipulations connected with the irrigation phase of ~ the Seedskadee Project. Plans for future ~sanagement of this area should be based upon anticipated conditions likely to exist after the Seekskadee Project ~ is completed. The section of the river from the Big Island Bridge to the Wyoming-Utah State Line is one of increasing turbidities. This accumulation of silt,is caused by tributaries, and intermittent streams which discharge tons of silt during spring run-off. Stream gradient is less through this section, allow- ing large shifting beds of sand and silt to move slowly through the area. An increase in water temperatures in this area, peaking at 79® F. at Green River, makes this a borderline river for salr~onids. Development of aquatic communities is largely restricted to those :organisms which are either highly mobile, such as the Ephemeroptera or those such as the Diptera which have few appendages for attachment. Algal growth and aquatic plant development is very light in the area, Organic pollution contributed by the town; of Green River and Rock Springs is-not in sufficient quantities to create septic conditions, but coliform or- ganisms are greatly increased and are beyond limits desirable for game fish waters. Industrial pollution by the U. P. Railroad has been greatly reduced during the last ten years. Occasioxsal, accidental, spills of oils into the river indicate that adequate safety devices are lacking in the disposal system.