2012-03-07_PERMIT FILE - C2010088 (28)

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McClane Canyon Mine Expansion and Fruita Loadout Facility Biological Assessment hydrologic cycle and water quality for Reed Wash appear to have been altered by surrounding land uses. Discharges in Reed Wash increase during April and May due to snowmelt, similar to East Salt Creek (Figure 1) but flows continue to rise throughout the summer and peak in September as a result of irrigation water returns from agricultural lands upstream (Figure 2, also see 'Bauch and Spahr, 2000). Also, total nitrogen concentrations in Reed Wash, 'including nitrife, nitrate, ammonia, and organic nitrogen, were ranked among the highest at national agricultural sites by the National. Water` Quality Assessment Program (Spahr. et al., 2000). Further, selenium concentrations have been elevated within the Reed Wash Basin in the past, ranging from 21 pg /L to 380 pg /L during 1992 (Butler et al., 1996). Elevated levels of insecticide (carbofuran) and herbicides (atrazine and 2,4 -D) have also been reported in Reed Wash, generally during the period of highest irrigation return flows (Bauch and Spahr, 2000). 200 CL M M 100 U L so U N 'a Month Figure 2 Average Monthly Discharge In Reed Wash, 1973 to 1983, Measured at USGS Gage 09163300 near Loma. Vertical Lines are Minimum and Maximum Monthly Flows. Reed Wash is within Lower Colorado River Stream Segment 13b which, as defined in Regulation 37, has a Use - Protected entidegradation designation (Regulation 31.8(1) {b }), a Warm Class 2. Aquatic Life Use classification, Recreation class E (existing primary contact use) classification, and tab_ le value standards (TVS) for levels of metal pollutants determined to be generally 'protective of Agriculture use. The TVS (the numeric standard) for selenium in Segment 13b is 18.4 pd /L (acute).and 4.6 pg /L (chronic). Reed Wash is included in Colorado's Section 303(d) list of Impaired Waters for impairment (with moderate priority) * due to concentrations of selenium (CDPHE Water Quality Control Commission, 2010). Selenium. in soils sampled at nine sites at the proposed Loadouffacility ranged from 0.84 to 10.60 mg/kg.' One water sample (April 2010) from Reed Wash upstream from the Loadout Facility reported 48 pg /L, and one sample (April 2010) taken downstream reported 47. jig/L. Selenium levels in both - samples exceeded ,selenium ' concentrations measured at the same time in the Colorado River upstream (2.6 pg/L) and downstream (3.1 pg /L) from Reed Wash.8 Exhibit 06, attached to CAM - Colorado, LLC Fruita Loadout, Colorado Division of Reclamation, Mining and Safety Permit No. C- 2020 -088. a Exhibit 03, attached to Permit No. C- 2020 -088. 8