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OJ1702 303(d) list and TMDLs developed, If the marginal cold water use was dropped from this segment, then the water temperature standard of 32,20C would probably not be exceeded, The standards for the different coldwater fishery uses, high quality cold water and marginal coldwater, would be the most restrictive, Based on historical data, the State's latest 303(d) listing and 305(b) report, and the low flow sample results, no acute fishery standards are expected to be exceeded over long term 250 cfs releases from Navajo Reservoir. Of the chronic fishery standards, it appears dissolved aluminum may be exceeded over the long term. One sample site (above Highway 44 bridge at Bloomfield, NM) had a dissolved aluminum result two times higher than the standard. The sample results from sites upstream and downstream had results of about 1/3 of the standard. The most likely standards to be exceeded over the long term between Navajo Dam and the Animas River confluence are water temperature, conductivity, total ammonia, dissolved oxygen, and total organic carbon. In initial discussions with the State on the low flow test, the State feels the antidegradation policy (section 20,6.4.8) in the Standards for Interstate and Intrastate Surface Waters would protect present stream segment water quality from further degradation due to flow releases from Navajo Reservoir. This section could provide the legal authority for the State to enforce the standards through court proceedings. The NM Environment Department realizes that Reclamation is attempting to return the San Juan River to a more natural hydrograph and generally supports that effort, Further talks are needed with the state to clarify issues on the long term effects of 250 cfs flows. The NM Environment Department expressed concerns about effects on National Pollution Discharge Elimination System (NPDES) permit holders if 250 cfs occurred during most of the year. These permits would be primarily for wastewater treatment plants and power plants along the river. The change in flows could affect the discharge limits on the permits which may require the permit holders to make changes in their operations, upgrade equipment, etc. Reclamation may conduct preliminary studies (from the dam to the confluence of the Animas River) to determine if permitted constituents change significantly at the wastewater treatment plants. In an earlier low flow test, the Four Comers power plant expressed concerns about managing Morgan Lake during low flows due to increases in TDS in the San Juan River. These low flows occurred during the four-month flow test (1996-97) in which flows between Farmington and Shiprock were around 200 to 300 cfs. According to the flow recommendations developed by the San Juan River Basin Recovery Implementation Program, 500 cfs would be maintained in the San Juan River between Farmington and Lake Powell. This flow would be higher than the critical low flows of the waste water treatment plants in Farmington and Shiprock and the two power plants in this reach, so the NPDES permits would not be affected, Long-term impacts to salinity should not be significant. Overall water volume delivered downstream of New Mexico will not change, just the timing, The large spring runoff period will have lower total dissolved solids, while the lower flows will have higher values, Results from previous low flow tests and historical data show total dissolved solids increase during low flows. Reclamation continues to look for ways to reduce salinity under the Colorado River Basin Page 14 of 15