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27 Recent data (1989-94) collected by Reclamation shows mean selenium levels in water samples from the Animas River at the pumping plant site are 5.7 ~g/l, with a maximum level of 28 ~g/l. Data collected from March to October 1993 showed average selenium levels of 6.4 ~g/l at the pumping plant site, with levels increasing downstream to 13.6 ~g/l at Aztec, New Mexico. The Service understands that there is some question as to the accuracy of this data. Fish and invertebrate samples were collected from the Animas River and the average selenium concentrations were 2.3 and 2.4 ppm respectively. These levels in fish and invertebrates are not indicative of a selenium problem. EFFECTS OF THE PROPOSED ACTION Colorado souawfish and razorback sucker Water Quantity When Project depletions are considered (Table 3), impacts occur under all conditions with further reduction in flow virtually every month. The months of April, May, June, July, and August of dry and average years displayed the greatest impact from the Project. Mean monthly flow reductions range from 3 to 27 percent in an average year (1945) at Bluff, from 4 to 41 percent at Shiprock, and from 3 to 42 percent at Farmington. For average years, the percent of flow reduction at Shiprock and Farmington in July is greater than at Bluff. The 1991 analysis only looked at conditions at Bluff, this analysis includes Shiprock and Farmington because the greatest concentrations of adult Colorado squawfish are found upstream of Bluff. Mean monthly flow reductions for a wet year (1949) are from 2 to 22 percent at Bluff, from 2 to 43 percent at Shiprock, and from 2 to 34 percent at Farmington. For wet years, the percent of flow reductions was highest in August; again the percent change in depletions at Shiprock and Farmington are greater than at Bluff. Dry years (1951) tend to reflect the most significant changes where flow reductions range between 1 and 61 percent at Bluff, between 2 and 43 percent at Shiprock, and between 3 and 30 percent at Farmi ngton. 2 In dry years, the greatest . percent of flow reductions occurs at Bluff in May, and at Shiprock and Farmington in July. Table 3 does not reflect any proposed operational changes of Navajo Dam as required in the reasonable and prudent alternative. 2 The calculation of changes in flow between baseline and post- Project was accomplished using Reclamation's model of the San Juan River. The modeled depletions at Bluff may vary somewhat from the Animas-la Plata depletions shown in Appendix B due to reservoir and diversion operations. The model is the best available, but has some limitations and may not reflect all current operational objectives for the Navajo Reservoir. The major difference lies in the way flood releases are treated. Present operations call for releases in anticipation of spring floods, while the model does not (i.e., spills occur). The changes between baseline and post- Project were modeled as they occur in the Project operation plan and accurately reflect the change in flow expected to occur.