2011-05-12_PERMIT FILE - M2011028 (2)

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CHAPTER 3 AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES Mitigation for Refined Alternative 4 Special Status Species Impact 1: Incorporate bypass flows into ALP Project operations to reduce the possibility of impacts to cottonwood recruitment. Refined Alternative 4 Special Status Species Impact 2 Significant: Implementation of Refined Alternative 4 could potentially affect the food base of bald eagles. Reclamation studies of bald eagle casts have indicated a high use of mammalian carrion in the diet of bald eagles; however, fish remains are less easily identifiable in casts. Ridges Basin Reservoir would expand the prey base of wintering eagles, when accessible, but contaminants could bioaccumulate in fish and affect bald eagles. Accordingly, Reclamation contracted with the NBS to conduct a contaminant impact analysis. The report evaluated data collected on water, sediments, invertebrates, and fish for the following: arsenic, boron, cadmium, chromium, copper, lead, lithium, molybdenum, mercury, nickel, selenium, silver, uranium, vanadium, and zinc. Results indicate mercury and selenium could be of some concern because they biomagnify through the food chain. Based on the assumptions used in the analysis, mercury could represent a hazard to eagle reproductive success due to ingesting contaminated fish. However, mercury levels in the Animas River exceed concentrations in similar systems. Selenium concentrations in soil and water samples are of concern, but concentrations in fish do not appear to be high enough to create a problem for fish-eating birds. In September 1999, Reclamation collected sediments, vegetation, invertebrates, and fish from Farmington Reservoir (an off-stream reservoir which receives its inflow from the Animas River and is serving as a surrogate for Ridges Basin Reservoir) for contaminant analysis. Mitigation for Refined Alternative 4 Special Status Species Impact 2: Develop and implement a monitoring program for potential adverse bioaccumulation of trace elements in bald eagle food items in conjunction with the Service, CDOW, NMDGF, and the Colorado Ute Tribes. Refined Alternative 4 Special Status Species Impact 3 - Potentially Significant: Construction of the NNMP could impact southwestern willow flycatcher nesting habitat at two crossings of the San Juan River. The southwestern willow flycatcher is known to nest in willows with a cottonwood overstory along rivers. Based on habitat structure, dense stands of Russian olive and tamarisk vegetation also provide the cover requirements for preferred willow flycatcher nest sites. The species occupies nest sites between about mid-May to about August. Willow flycatchers overwinter in Mexico, Central America, and possibly South America, and the species begins to migrate during late fall to these areas. Surveys conducted in October 1999 at the location of the proposed San Juan River crossing of the NNMP determined that flycatcher habitat would not be adversely affected during construction and operation of the pipeline. However, construction noise or physical disturbance of nest sites during the critical mid- May through August nesting period may adversely affect flycatcher breeding success. Mitigation for Refined Alternative 4 Special Status Species Impact 3: Schedule construction of pipeline crossings to avoid construction during periods when the southwestern willow flycatcher is present. Directional boring from the shoreline, using equipment placed outside of the line of trees lining the banks of the San Juan River would minimize the direct impact to riparian vegetation. Construction during the September to May time period would avoid the willow flycatcher-nesting season. Weerninuche Construction Authority P.O. Pox AA - Touiaoc, CO 31334 3-117 jst_? ? r+l As 6t.AGtIF-(L G RtaV ta- ev.kA t(bC(- l-k -pAG§E 14-9cn 3.7 SPECIAL STATUS SPECIES