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• Comprehensive Analylinl Results Report FastaM West Wi11oW Creek The most significant increase in load along this stream segment occurs where Windy Gulch enters Willow Creek above Creede and the dissolved zinc load increases by approximately 24 percent from 258.57 ppd at SW-28 to 319.94 ppd a[ SW-29. Windy Gulch at SW-16 is contributing 62.96 ppd. Metals concentrations, flow rate, and load are remarkably consistent along Willow Creek. I ._------.- However, it would be a mistake to conclude from this that sources located along Willow Creek do - ~ not contribute to the metals load. Rather, it is likely that the stream, bed sediments and widespread _. __ _. -~ source material are in equilibrium and metals concentrations are not fluctuating widely as a result. -~ It should be noted that Willow Creek is a braided stream below Creede with most of the flow ~ carried in two to three main channels. Samples 31/32 and 33/34 should be combined when evaluated for flow and loading considerations. ~'~=~ Sediment sample SE-32 exhibits elevated concentrations for a number of organic analyzes including ~- _-~ ~e volatile organic compounds acetone, carbon disulfide, and 2-butanone as well as several semivolatile organic compounds as depicted in Table 6. The combined concentration of these analyzes is 4,542 µg/kg. It is likely that the source of the organic contamination in 5E-32 is related to the abandoned railroad line or the highway which are located a short distance to the east. 5.3.5 Rio Grande River(SW/5E-35 through SW/SE-40) All Rio Grande River release samples exhibit elevated concentrations of zinc fot surface water (both total and dissolved) and sediment samples. Although zinc concentrations decrease downstream of the Willow Creek confluence, the TVS is still exceeded at SW-40, the most distal sample in this study, collected at Palisade campground 12 miles downstream of the Willow Creek and Rio Grande confluence. The TVS is hardness dependent but averages 33 µg/1 for this segment of the Rio Grande. SW-37 is elevated for dissolved lead and SW-37 through 40 are elevated for total lead. For total lead the elevated concentration determination is based on using SW-35 for background comparison. Lead and cadmium are also elevated in sediment samples 5E-37 through 40. Loading calculations for Rio Grande release samples are computed in Table 8 but were not plotted on the histograms because they are not representative of the true load which the river is carrying. 12