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~; Memo to Christine Johnston Mt. Gunnison No. 1 Subsidence Inspection page 3 identified. ~t@n~-the-less the probabY2- hydrologic"consequences (PHC) statement and the subsidence inventory statement of the ~rmi.t will now have to be amended by West Elk Coal. In addition ~i S~lieve it would be appropriate for W2st Elk to add the spring to. ~hei~ hydrologie monitoring plan-'. It has been shown in the case of both the Mt. Gunnison No. 1 and the Orchard Valley mines, that ground water wells impacted by subsidence of underlying mine workings tend to initially dewater and subsequently return to their pre-subsidence water levels within a year or two. While we have no documented observations regarding subsidence impact upon springs, I would anticipate a similar scenario. The spring might relocate to a lower location stratigraphically. However, I would expect the flow to reestablish within a year or two. ~t appears that this spring has followed c#1~ scenario: I would also anticipate that West Elk Coal's undermining within the "B" Seam may have a similar impact. I would anticipate that the impact might be muted by the additional 430' of overburden thickness. I also expect that the spring flow might continue to recover for the next year and then decline as the "B" Seam subsidence occurs. I would not be surprised if the spring relocated itself once again to a lower stratigraphic horizon. Monitoring of the spring should allow careful determination of the impacts of undermining. Mr. Mautz seemed genuinely relieved to discover that the spring flow had reinitiated. He stated that his primary desire was to have a sufficient water supply to rehabilitate his historic domestic use of the homestead cabin site. I recommend that we encourage Mr. Mautz and West Elk Coal to negotiate an agreement to address the protection of Mr. Mautz's decreed water right. Mr. Barbe reported that he would present his observations to his management for consideration. Failing an amicable agreement within a reasonable time period, perhaps several months, we should require the operator to propose a plan for the monitoring and protection of Mr. Mautz's water right. I further recommend that you include these observations in your inspection report. If you prefer you may attach a copy of this memorandum. In addition, copies of all correspondence dealing with this topic should be provided to Mr. Mautz. cc: David Berry Steve Renner DoC: M:\MIN\JAP\MTGSUB.MEM JP/]P