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Sandra Brown March 7, 2012 Page 9 seep water with the river water to get a combined flow rate and combined iron and temperature values. All available total iron data from 2010 were utilized for the seep and an average value of 1.9 mg/l was obtained. BCC samples the North Fork of the Gunnison River 3 times /year in June, August, and December and all available total iron values for the North Fork upstream site were averaged to obtain a value of .47 mg/l. The same method was used to obtain an average temperature value for the seep of 39.8 °C and an average temperature value of 10.1 °C for the upstream site on the river. The flow for the seep is estimated to be 4 gpm (this is probably a high estimate given the treatment pond discharges constantly at @ 3.6 gpm). An average flow for the river obtained from June, August, and December 2010 was calculated to be 457 cfs or 205102 gpm. Therefore, combining 4gpm (seep water) with an iron concentration of 1.9 mg/l to 205102 gpm (river water) with an iron concentration of .47 mg/l results in a combined flow of 205106 gpm with a total iron concentration of .470028 mg/l. Using the same data set for temperature, results in an average temperature in the river of 10.1' C and 39.8° C for the seep. The end result is an overall temperature increase from 10.1° C to 10.10058° C. As can be seen from this example there is very little change in iron concentration and temperature in the combined flow of the river. The primary reason that the WQCD denied BCC's 2008 request to amend the CDPS permit and allow for direct discharge to the river was because of total iron concentrations in the seep water exceeding the discharge limitations. The WQCD also states that the seep is a discharge of pollutants to state waters. Recent data do not show this to be case. It's difficult to determine why some of the earlier sample results were slightly elevated for total iron, possibly sample collection technique or laboratory issues. Since mid -late 2008, samples from the seep have shown total iron concentrations below the CDPS limitations. The discharge from the treatment pond outflow with regard to total iron concentration is the same order of magnitude as the seep water and in fact very similar laboratory results are obtained from the pond outflow versus the seep. Thus, the effect on the river is the same with regard to combined flow and the resulting combined total iron concentration regardless of whether the treatment pond is in place or not. Conclusion & Recommendations The Division has studied this site for nearly fifteen years and conducted numerous observations and inspections of the site. Two issues remain that have not been fully explained; the source of the water and the heat source for the elevated temperature of the hillside seep. These may never be fully understood without a substantial subsurface investigation which seems economically unreasonable given the low flow and the relatively good quality of the seep water. Additional site investigation may be technically infeasible as well considering the limited access and mountainous terrain. Additional disturbance in unstable terrain characterized by steep slopes and active landslides is unwarranted. It appears most plausible that the waters which emanate from the hillside seep and likely initiated the landslide activity issue from the bedrock strata beneath the colluvium comprising the failed landslide mass. Dr. Jim Pendleton makes a very important conclusion in his February 17, 1998 memo regarding his investigation of the landslide. He concluded the following. "...the geothermal groundwater discharge referred to by WWE as the "Edwards Portal spring" is an