Laserfiche WebLink
McClane Canyon Mine Expansion and Fruita Loadout Facility Biological Assessment <br />hydrologic cycle and water quality for Reed Wash appear to have been altered by surrounding <br />land uses. Discharges in Reed Wash increase during April and May due to snowmelt, similar to <br />East Salt Creek (Figure 1) but flows continue to rise throughout the summer and peak in <br />September as a result of irrigation water returns from agricultural lands upstream (Figure 2, also <br />see Bauch and Spahr, 2000). Also, total nitrogen concentrations in Reed Wash, including <br />nitrite, nitrate, ammonia, and organic nitrogen, were ranked among the highest at national <br />agricultural sites by the National Water Quality Assessment Program (Spahr et al., 2000). <br />Further, selenium concentrations have been elevated within the Reed Wash Basin in the past, <br />ranging from 21 pg /L to 380 pg /L during 1992 (Butler et al., 1996). Elevated levels of insecticide <br />(carbofuran) and herbicides (atrazine and 2,4 -D) have also been reported in Reed Wash, <br />generally during the period of highest irrigation return flows (Bauch and Spahr, 2000). <br />150 <br />100 <br />so <br />0 <br />l l l l <br />Apr May Jun Jul <br />Month <br />Figure 2 <br />Average Monthly Discharge in Reed Wash, 1973 to 1983, Measured at USGS Gage 09163300 near <br />Loma. Vertical Lines are Minimum and Maximum Monthly Flows. <br />Reed Wash is within Lower Colorado River Stream Segment 13b which, as defined in <br />Regulation 37, has a Use - Protected antidegradation designation (Regulation 31.8(1)(b)), a <br />Warm Class 2 Aquatic Life Use classification, Recreation class E (existing primary contact use) <br />classification, and table value standards (TVS) for levels of metal pollutants determined to be <br />generally protective of Agriculture use. The TVS (the numeric standard) for selenium in <br />Segment 13b is 18.4 pg /L (acute) and 4.6 pg /L (chronic). <br />Reed Wash is included in Colorado's Section 303(d) list of Impaired Waters for impairment (with <br />moderate priority) due to concentrations of selenium (CDPHE Water Quality Control <br />Commission, 2010). Selenium in soils sampled at nine sites at the proposed Loadout Facility <br />ranged from 0.84 to 10.60 mg /kg.' One water sample (April 2010) from Reed Wash upstream <br />from the Loadout Facility reported 48 pg /L, and one sample (April 2010) taken downstream <br />reported 47 pg /L. Selenium levels in both samples exceeded selenium concentrations <br />measured at the same time in the Colorado River upstream (2.6 pg /L) and downstream (3.1 <br />pg /L) from Reed Wash. <br />Exhibit 06, attached to CAM - Colorado, LLC Fruita Loadout, Colorado Division of Reclamation, Mining <br />and Safety Permit No. C- 2020 -088. <br />8 Exhibit 03, attached to Permit No. C- 2020 -088. <br />8 <br />Aug Sep Oct Nov Dec <br />