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average, 35 mg/l) occurred in April and Nay with values of 38 and 56 mg/l, respectively. <br />In addition, the daily maximum TSS limit (70 mg/l) was also exceeded on May 11, 1993 with <br />a value of 232 mg/l. As stated earlier, the repairs to the dewatering line have been <br />complete; therefore, further excursions are not expected. A letter to the CDOH explaining <br />these excursions is found with the associated DNRS in Appendix F. <br />NPDES 006 also exceeded the NPDES 30-day average TSS limit (35 mg/l) in April with a value <br />of 37 mg/l. In addition, the 30-day average total iron limit (3.0 mg/l) Was exceeded in <br />May with a value of 3.62 mg/I (later retested by the laboratory to actually be 3.10 mg/l). <br />Both exceedences were a result of high snowpack runoff. More details to these exceedences <br />may be found in a July 28, 1993 letter to the CDOH (see Appendix P). <br />Surface Water Summary. The limited amount of mining that has occurred at this mine <br />(mining began in 1990) has had little effect on surface eater quality. NPDES 006 actually <br />experienced a 60 mg/l decrease in its annual average TDS value from last year as a result <br />of higher snoupack runoff. Site SG7 (Upper Hubberson Gulch) had an annual average TDS <br />value below that of its baseline range. All other stream sites and all NPDES sites had <br />average annual TDS values falling within the baseline ranges. <br />R eferent es <br />American Public Health Association (Ed.). 1985. "Standard Methods for the Examination of <br />Water end Wastewater", 16th Edition, Washington, D.C. <br />Colorado Department of Health. 1986. "The Basic Standards for Ground Water Draft Copy <br />(April)". <br />____ 1991. "Classifications and Numeric Standards - Upper Colorado River Basin and <br />Nor [h Platte River (Planning Region 12)". <br />Environmental Protection Agency. 1976. "OUality Criteria for Water" <br />Office of Surface Nining Reclamation and Enforcement. 1989. "Draft Environmental Impact <br />Statement, OSNRE-E15-25". <br />14 <br />