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Site HGSD1 is upstream of the Loadout. This site is normally monitored <br />twice a year, once in the spring and once in the fall. This site <br />displays an increasing IDS trend, with the TDS peak occurring in October <br />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 4 provides a comparison of this year's surface water quality to <br />CDPHE receiving stream standards for lower Dry Creek (Yampa Segment 13h, <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 />listed 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 4 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 />HGT ran selenium in three forms this year, often on the same samples, so <br />as to investigate the difference in the three methods. However, in a <br />regulatory sense, the potentially dissolved form is applicable to NPDES <br />sites, and the dissolved form is applicable to stream sites. The total <br />recoverable form was run only as a quality control check. The following <br />discussion will focus only on potential dissolved excursions at NPDES <br />sites and dissolved excursions at steam sites. There were no excursions <br />at NPDES Sites this year. <br />The chronic selenium standard (4.6 ug/1) was exceeded twice at upstream <br />Site HGSDI; 107.0 ug/l in March and 62.1 in May. Downstream Site HGSD3 <br />exceeded the chronic standard once; 7.8 ug/l in May. The acute standard <br />(18.4 ug/1) was exceeded twice at Site HGSD1. Irrigation return water <br />from the hay fields is in part the cause of the excursions at these <br />sites. This entire area is composed of topsoils derived from the Lewis <br />