Laserfiche WebLink
December 5, 2013 <br />To: Brock Bowles <br />From: Susan Burgmaier <br />Re: Elk Creek Mine (Permit No. C- 1981 -022) <br />2012 Annual Hydrology Report <br />Request for Assistance with Review <br />Per your request, I have reviewed portions of the 2012 Annual Hydrology Report for the Elk Creek Mine. <br />You indicated that you reviewed the report to determine whether sampling had been done in <br />accordance with the approved permit, and requested that I direct my attention to the items you <br />identified as possible problems. Accordingly, my review is limited to the list of surface water quality <br />concerns you identified, presented below in a format suitable for forwarding to the operator. <br />1. The Division identified concerns with increased concentrations of chloride, nitrate /nitrate, total <br />suspended solids, and orthophosphate; I have for Oxbow Mining, LLC ( OMLCC) only made mention <br />of the elevated chloride levels. When there are significant deviations from baseline averages, in <br />accordance with Rule 4.05.13(4)(c)(iii), the Division will require OMLCC to provide a summary and <br />discussion of the data, and offer any available information to assist in determining the cause of <br />the change. In order to better identify trends and impacts, the summary should be based on data <br />over the life -of -mine monitoring period, rather than being limited to the water year reported. <br />Surface Water Locations on Hubbard Creek: <br />2. Chloride at H -1 — OMLCC mentions the elevated chloride concentration but notes that there is no <br />apparent reason for the spike. Elevated chloride levels were also observed at the Bowie Resources, <br />LLC (BRL) Bowie No. 2 Mine, at upstream and downstream sites, during the 2012 water year, also <br />with no obvious explanation. The West Elk Mine also reported elevated chloride concentrations at <br />some of their monitoring locations, and indicated that low flows might be a contributor. Since the <br />elevated chloride levels are observed both upstream and downstream in other tributaries of the <br />North Fork, it does not appear to be a mine related impact, and is likely a function of the drought <br />conditions present during the 2012 water year. The Division will continue to monitor the chloride <br />concentrations to better determine whether it is an ongoing trend or an anomaly. <br />3. Nitrate /Nitrite at H -1 — OMLCC does not make mention of or offer an explanation for the increased <br />nitrate /nitrite concentration. The upstream and downstream sites at Bowie No. 2 were also <br />elevated, which again indicates that this may not be mine related. The Division will monitor future <br />data to determine whether the condition is present in normal flows, and whether or not it could be <br />mine related. <br />4. Total Suspended Solids (TSS) at H -1— OMLCC does not make mention of or offer an explanation for <br />the increased TSS. Historic data at H -1 show similar spikes in 1986/1987 and 1995, with normal <br />