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SUMMARY (Continued) {~?:~~ The canal and lateral lining alternative was formulated by includ- ing several separable and distinct increments which could be con8tructed independent of other increments. Each increment consisted of all canals and lateral8 to be lined in a particular subarea. E8ch increment also was planned to be a logical and practical part of the delivery system such as an entire lateral system and/or a major unbroken segment of canal. E8Ch increment would be large enough to accommodate modern con- struction equipment and practices, to provide for continuity and ease of operation and maintenance, and to enable the determination of salt load- ing attributable to the increment. The recommended plan was formul8ted by eliminating those canal lining increments whose cost effectiveness exceeded the level currently being considered for units of the Colorado River Water QU8lity Improvement Program. The accomplishments, features, and consequences of the recommended plan and the no-action alternative are summarized in the table on the following page and di8cussed in the following sections. Recommended plan Under the recommended plan, 55.5 miles of canals and later8ls in the Uinta Basin Unit area would be concrete lined to reduce seepage and thereby reduce salt loading to the Colorado River by an estimated 21,000 to 30,000 tons per year (adjusted to account for the increase resulting from wildlife mitigation). Because of the uncertainties in some vari- ables used in the hydro"alinity analysis, reasonable ranges for these variables were defined which resulted in a range for the salt 108d re- duction for the unit. This 8alt load reduction would be accomplished at an average cost effectiveness of $88 per ton of salt removed. The reduced canal seepage would also result in an increased water supply to presently irrigated lands of about 16,800 acre-feet of water annually; however, because of its seasonal availability, shortages would be re- duced by only about 4,600 acre-feet. A contractual agreement would be executed with the water users requiring that this water only be used on presently irrigated lands. The plan also provides for mitigation meas- ures to compensate for wildlife habitat losse8 which would occur. The recommended plan includes concrete lining 43.9 miles of canals and 11. 6 miles of laterals involving nine c8nals in six subareas-- Zimmerman Wash, Pleasant Valley, Gray Mountain, Pahcease, South Fork Dry Gulch, and Purdy-Midview. Nearly 50 percent of the canals and laterals to be lined have capacities of 15 cfs or less. Only about 25 percent are in the 60- to 360-cfs range, and these sections are all p8rt of either the Gray Mountain Canal in the Gray Mountain subarea or the Upper Pleasant Valley Canal in the Pleasant Valley subarea. wildlife measures would include providing 2,000 acre~feet of water annually to enlarge the Bureau of Land Management P8riette Wetland De- velopment Area by 627 acres to compensate for ripari8n and wetland habi- tat which would be lost as a result of project development. The mitiga- tion plan would also include con8tructing big game bridges and escape ramps along the concrete-lined canals where deer mortality could occur S-6 cue 4, 1