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<br />OOllO74 <br /> <br />in their effort to identify additional salinity control measures on Federal <br />lands. <br /> <br />~ <br /> <br />4. Continuing effort is needed to resolve differences in economic evalua- <br />tion and estimates of salt loading between Reclamation and SCS. We need to <br />again coordinate our respective program schedules so that our construction <br />activities mesh with SCS efforts in a comprehensive program. <br /> <br />5. Additional efforts should be made by the Forum or the Work Group to <br />evaluate impacts of the NPDES program and develop ways to enforce the zero <br />discharge policy. <br /> <br />6. Assuming additional water supplies are passed to the lower basin, the <br />CREST program from 1986 through 1990 has potential to provide a near-term <br />safety factor by reducing average salinity at Imperial Dam by 13 mg/L, thus <br />reducing the risk from unavoidable project delays or adverse hydrology. <br />In the long term, beyond 1995, the basin-wide operational program has the <br />potential, when combined with the presently envisioned WQIP projects, of <br />providing sufficient salinity reduction to carry the basin into full develop- <br />ment, while exceeding the numeric criteria 25 percent of the time. <br /> <br />7. Since initiation of CRWQIP in 1972, unit cost effectiveness or unit costs <br />have steadily increased, while estimates of salt reduction have been reduced. <br />The graphs show a broad range of current cost-effectiveness under which the <br />present management strategy is to select the most cost-effective units for <br />implementation. However, cost-effectiveness and unit reductions are only <br />part of program implementation criteria. (Figures 3, 4, and 5 shows unit <br />cost effectiveness.) In reaching our target salt load removal rates, more <br />expensive units will have to be considered. <br /> <br />8. In evaluating the CRSS and Forum projections, figures 6 and 7, we see <br />that there are different viewpoints in evaluating future salinity increases. <br />It should be emphasized that salt reduction program objectives are considered <br />"movi ng targets," subject to different assumpt ions regard i ng future basi n <br />hydrology, depletion levels, and other natural phenomena affecting salinity <br />in reservoirs. <br /> <br />. <br /> <br />9. In evaluating figures 9, 10, 11, and 12 that were developed from CRSS, we <br />conclude that under the most favorable salinity control prOjections (includes <br />WQIP case and CREST case), within the average salinity concentration levels <br />maintained at about 820 mg/L, a significant reduction in damages, over those <br />projected, would occur in the U.S. 75 percent of the time. Conversely, even <br />with the most favorable salinity control projections, there still is a 25 <br />percent probability that we will exceed the salinity TDS numeric criteria <br />standard of 879 mg/L at Imperial Dam in any given year past 1990. <br /> <br />10. In eval uating figures 13 and 14, we have compiled the total salt reduc- <br />tion impacts of the USDA and USBR water quality improvement projects and <br />cloud seeding programs on a time scale. Also shown are the target reduction <br />requirements to meet the TDS numeric criteria standards under future condi- <br />tions. The level of program accomplishments is shown at 100 percent in <br />figure 13 and 50 percent in figure 14. A 100 percent accomplishment level <br />represents implementation of all identified projects, regardless of cost or <br /> <br />16 <br />