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Site HGSDI is upstream of the Loadout. This site recently displays a <br />stable TDS trend, with the TDS peak occurring in October 2002. <br />Site HGSD3 is downstream of the Loadout. This site indicates an <br />increasing TDS trend, with the peak TDS occurring in April 1995. <br />Table 3 provides a comparison of this year's surface water quality to <br />CDPHE receiving stream standards for Dry Creek (Yampa Segment 13d, <br />Regulation No. 33, January 2009). This Paradox database generated table <br />does not include the units of concentration (mg /l or ug /1) for each <br />parameter. The units used for each parameter are the same as those <br />�i.sted on the Surface Water Parameter List (Table 1) and are also the <br />same as those used in the water quality reports. The frequency column on <br />Table 3 indicates, in this order: uncensored, that is, the number of <br />exceedances above the Method Detection Limit (MDL) / the number of <br />exceedances between the MDL and the Practical Quantitation Level (PQL) / <br />censored, that is, the number of sample values below the MDL but the MDL <br />was higher than the standard / the total number of samples. Below is a <br />summary of standards that were exceeded. <br />For upstream Site HGSD1, the pH standard (6.5 -9.0) was exceeded in <br />September with a value of 9.1. High pH values are normally associated <br />with algal growth. <br />For downstream Site HGSD3, the total recoverable iron standard (1.0 <br />mg /1) was exceeded in September with a value of 1.40 mg /l. Neither NPDES <br />outfall was discharging at the time. <br />For downstream Site HGSD3, the nitrite standard (0.05 mg /1) was exceeded <br />in September with a value of 0.09 mg /l. Neither NPDES outfall was <br />discharging at the time. Nitrites are unstable in aerated water, and <br />will oxidize to nitrates. <br />The chronic selenium standard (4.6 ug /1) was exceeded in September at <br />both stream sites, HGSD1 and HGSD3, with values of 4.9 and 18.9 ug /l, <br />respectively. The acute standard (18.4 ug /1) was also exceeded at Site <br />HGSD3. Irrigation return water from the hay fields above upstream Site <br />3 <br />