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fv1 Q'-L I q &':2. (:,:) ,-;) ,") '.-l ,-:J In November, the Bureau of Reclamation will be asking the Rio Grande Water Conservation District and the State of Colorado Water Conservation Board for concurrence for the start of Stage 3 Canal and Lateral construction, as required by Section 101 (b) of Public Law 92-514 (86 Stat. 964), the authorizing legislation, as amended by Public Law 96-375 (94 Stat. 1507). ~~..., ..,,,.... Our plan of development provides for stage construction of project features over an 8 year period and provides assurance to local and State of Colorado interests that pumping of the shallow ground water will not adversely affect ground water conditions in the valley. The Definite Plan Report, page B-6, gives a range of 22,000 to 30,000 acre-feet per year, ground water yield estimate for Stage 3. Completion of test wells in Stage 3 showed that this stage will produce about 37,000 acre-feet per year. Our well spacing model and Geologic Survey's computer model shows pumping Stage 1-2 at 13,143 acre-feet per year, and Stage 3 at 37,000 acre-feet per year will not violate any boundary conditions as required by the amended legislation. Article III of the Rio Grande Compact states: "In the event any works are constructed after 1937 for the purpose of delivering water into the Rio Grande from the Closed Basin, Colorado shall not be credited with th~ amount of such water delivered, unless the portion of sodium ions shall be less than 45 percent of the total positive ions in that water when the total dissolved solids in such water exceeds 350 parts per million." Based on water samples from approximately twelve (12) salvage wells and four (4) test wells, in Stage 3, the unconfined ground water has a combined mixed total dissolved solids content of 318 parts per million (ppm) and a combined mixed sodium ion conconcentration of 45 percent of the total positive ions. This water quality is well within Article III of the Rio Grande Compact require- ments. Our salvage well water quality mixing model shows no problem with water quality when blending Stages 1-2, 3, 4, and 5 water. Please refer to the water quality sheets for mixing results. Using the information from Stages 4 & 5 Pump Test Wells, we have completed our well spacing for these stages. Stage 4 will require about 42 wells and will produce about 31,000 acre-feet of ground water per year. Stage 5 will require about 25 wells and will produce about 14,000 acre-feet of ground water per year. Stages 1-2, 3, 4, and 5 will require about 168 wells and will produce about 96,000 acre-feet of ground water per year. We are establishing a control system of observation wells in Stages 1-2, 3, 4, and 5 which will provide positive identification of any fluctuations in the water tables, as required by Public law 92-514, Sec. 102 (a). Stages 1-2 and 3 observation wells are complete. We have under contract nineteen (19) obser- vation wells in Stages 4 and 5. The remaining eleven (11) wells will be completed the first quarter of 1984. The project will have a total of 68 per- manent observation wells.