2010-11-03_INSPECTION - M1977300

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(Page 2) MINE ID # OR PROSPECTING ID #: M-1977-300 INSPECTION DATE: 18 October ?010 INSPECTOR'S INITIALS: DR? OBSERVATIONS This inspection was conducted by Tony Waldron and David Bird of DRMS to check the progress of Technical Revision TR-14, characterization of source term materials, and Technical Revision TR-15, expansion of the alluvial ground water capture and treat system. DBMS was also following up on recent incidents at the site, including: 1) The failure of a pipe associated with the pump and treat system that resulted in a small quantity of alluvial ground water being spilled on the ground surface, 2) new discoveries pertaining to the mystery pipe, and 3) an overflow condition at the treatment plant that resulted in transfer of pre-treated water to the concrete holding ponds and subsequent discovery of a leak in the holding pond. Representing the operator on the inspection were Gus Gaviotis, Vice-President of Accounting and Finance; John Hamrick, Vice President of Milling, Amory Quinn, President of Cotter Corporation, and Randy Whicker, Health Physicist. Excavation of trenches was well underway for the purpose of burying water lines associated with the water treatment plant, and for installation of the new sumps approved under TR-15. However, due to an unexpected release from an upstream source, Ralston Creek was flowing at a relatively high discharge rate (100-200 gpm), which had the unfortunate consequence of re-saturating the alluvium and inundating the newly excavated trenches. Activity on the trenches and sumps has been suspended pending approval from CDPHE under the discharge permit to install pumps and relocate the water in the trenches to the stormwater retention pond. The installation of additional sumps under TR-15 was initiated in part by the discovery that, prior to the upstream release, stream flow volumes measured near surface sampling point BPL were significantly exceeding the discharge volumes from the alluvial water treatment plant. At that time, which was prior to the upstream release, the treatment plant discharge appeared to be the sole source of surface water flow in Ralston Creek. There was also the discovery of what appeared to be a surface seep on the south bank of Ralston Creek near sampling point BOS. These observations seemed to indicate that the existing network of sumps ( Sump #1, MW 9 & Sump # 4)_have not been able to fully intercept and capture the entire alluvial flow. As a result, uranium levels in Ralston Creek continue to be elevated above drinking water standards. Concurrently with the excavation of the trenches for the water transmission lines, Cotter has also started sampling and analytical activities approved under TR-14. Cotter is gathering soil samples from the trenches and has set up a small analytical lab inside the office trailer to analyze the soil samples for gamma emission and for X-Ray fluorescence using a hand-held Innov-X Systems analyzer. New findings regarding the mystery pipe, originally discovered discharging water to the stormwater retention pond, now suggest that the pipe is the remnant of an angled core hole drilled toward the mine at about a 45 degree downward angle. Cotter speculates that the hole was drilled in the 1960's as an exploration core hole to evaluate ore at depth beneath existing workings at the time. Due to mine pool and pond water levels that appear to fluctuate in concert, it appears that the hole is connected to the mine pool. However, the water in the pipe is not under hydrostatic pressure and the flow is easily stopped by either plugging or by raising the pipe a few feet above the pond. Mr. Quinn was quick to point out that the situation was being properly managed and all discharges from the pipe have been stopped. The treatment system overflow was a result of overloaded filters, which was caused by excess sedimentation of the sumps that resulted from the flooding situation due to the upstream release. DRMS feels that neither the treatment overflow nor the pipe failure event warrants a violation at this time because: 1) The events occurred either as a consequence of or in conjunction with corrective actions ordered by DRMS, 2) Cotter responded promptly to the incidents, 3) the quantities of release from both events were relatively minor, and 4) the waters released are within the area of capture of the pump and treat system and are essentially the same water as that occupying the alluvium. DRMS does regard these events as spills under Rule 3.1.13 and will cite this as a problem under item 1 on page 4 of this report along with the corrective actions, and the Division will continue to review this matter with respect to a possible violation.