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perimeter to be filled to a grade elevation of 4,920 feet. This will requir-e less than 2 feet of fill. The drainage ditch along the east perimeter requires treatment to raise the existing gr::>und surface to an elevation of 4,922 fee't. Similarly, this will require less 1:han 2 feet of fill. d. See:Jage Losses. From the effect:ive lengths of 200 feet in Zon,a Band 900 feet in t:he remaining areas, seepage losses for reaches along the lake WE:re determined. Transitions bet/leen different lakeside effective blanket lengths were traated by using transiticm zones, and the flow rates per lineal foot for the two effective lengths were averaged. For the worst-case condition of low river stage and a lake level elevation at 4,926 feet, a reasonably conservative se'=page loss of 1 cfs (450 gpm) can be expected. For this condition, nearly 70 percent of seepage loss will disch"lrge along the Uncompahgre River bank. e. Exit Gradients and Uplift. The effectiveness of the blankets was analyzed to determine if 1:he exit gradients will induce piping, heaving, uplift, or boils. ~rhe seepage (flow/lineal fo::>t) is 1:he greatest along the Uncompaghre River since the lakeside blanket is thE' shortest and there is no landside::>lanket. The exit gradient at the toe of the levee was deternined by a flow net analysis. An exit gradient of 0.2 was computed, which is well below the theoretical critical exit gradient of 1.0. Therefore, a satisfactory c01dition exists. Uplift or :leaving along the north perimeter of the lake was analyzed. 'rhis area is not likely to experience any displacement or boils near the lands ide toe. Any seepage 100 feet beyond the toe of the embankment should not significantly a Efect planned developmen.t which does not include structu:,:es. Exit heads along t:he east perimetex of the lake were computed and re:mlted in values half of the critical exit head, indicatinq a satisfactory condition. The south ]Jerimeter is not critical since the net head is zero. Any disturbance along the lands ide blanket could result in boils or other unstable conditions which will weaken the embankments and increase seepage. Flow rates for each reach assume that 'the blanket remains undistu::bed wit:h no penetrations and excavations. Any modifications to the blankets would require a reanalysis of seepage losses. It is recommended that any lakeside explorations or excavat.ions other than lake deepening will be filled with clay, bentonite - soil slurry mixt:ure, or grout. Explora1,:ions or excavations on the lands ide blanket should be fille,! with native impermeablE" materials (K< 1x10-6 cm/sec). The drainage ditch along the east perimeter of the sewage lagoon should be reloca.ted beyond the lands ide blanket or the 1/ater should be discharged through a buried 13