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Colorado Division of Minerals and Geology (DMG) <br />Coal Program <br />Installation, Operation, and Abandonment <br />of Coal Mine Methane Drainage/Monitoring Wells in Colorado <br />The purpose of this guidance document is to provide a framework for the permitting of <br />methane drainage wells to ensure that appropriate installation, operation, and <br />abandonment procedures are considered during the permitting phase and included in <br />any permitting approval. This document is intended to provide consistency in <br />requirements from site to site and minimize impacts during and after operations. <br />Methane drainage wells are utilized in underground coal mine operations in Colorado. <br />The methane drainage wells are typically drilled and installed above projected longwall <br />panels for the purpose of pre- and post-mining gas removal. Reducing methane <br />content in the mine significantly contributes to mine safety and productivity. <br />With the continued advance of longwall technology for extracting coal in Colorado, the <br />need for removal of methane gas in the mine has become common practice. DMG has <br />jurisdiction for permitting and approving these holes as part of the permit. The <br />permitting process is intended, in part, to prevent potential groundwater contamination <br />or gas seepage to the surface. <br />The life cycle of a methane drainage well can be summarized in four phases; <br />• Permitting <br />• Installation and Completion <br />• Operation <br />• Abandonment <br />Permitting - Rule 2.05.3 (1). (2)(b) and (3) and 3.02.2 <br />The need for methane drainage/monitoring wells is often urgent when the operator <br />encounters unexpected gas concentrations and the permitting time frame becomes <br />compressed. It is necessary to ensure that appropriate permitting materials are <br />included and are not overlooked due to time constraints. <br />Permitting of these holes should typically be done as a technical revision to the permit. <br />The permit document must be revised to include the details on necessary access roads: <br />and installation, completion and abandonment information for each hole. The permitting <br />materials submitted by the operator may vary but at a minimum should include a <br />detailed text discussion addressing road construction and reclamation, the installation, <br />completion, operation, and abandonment of each hole and a reclamation cost estimate. <br />Well completion information should include a proposed completion design diagram. <br />Maps and proposed diagrams must be included with enough detail to allow the <br />conclusion that impacts will be prevented or minimized to the extent possible.