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plans. Discussions ensued about the value of each, and by a hand vote, the public recoDDDended a plan. A close vote determined that concrete lining all canals and laterals which could be justified under the salinity reduction objective would be the desired plan. Where field conditions warrant, flexible lining would be considered if concrete lining were determined to be infeasible. In determining the extent and range of lining, planners initially determined the cost of intercepting salinity contributions from var10US portions of the study area. The planners concluded that, based on appraisal-level information and analysis, about 80 percent of the salt attributable to canal and lateral seepage 1n the valley could be removed for about half the cost of lining all canals and laterals in the valley. These initial conclusions were based on three analyses and later a fourth analysis. Analysis I consisted of canal and lateral increments which individually had a cost-effectiveness equal to or less than $450,000 per mg/L, based on January 1979 cost estimates. Analysis II consisted of all increments where the net cost-effectiveness of all increments equalled $450,000 per mg/L. Analysis III consisted of all increments in the valley, and the net cost-effectiveness of these incre- ments was estimated to be $574,000 per mg/L, based upon unit prices and estimated impacts then being used. Because of difficulty in making a selection from among the three analyses, a fourth analysis was performed based on a graphing of avail- able cost effectivenenss information for discrete increments of the distribution system. An obvious break in relative cost-effectiveness of the various canal and lateral increments was identified and a plan was formulated using those reaches that were the most cost-effecti~Ol1D~9 plan consisted of concrete-lining all increments on the east side of the 18