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May 11, 2011 <br />Page 6 <br />• Accurate location and pad elevations for the gas wells should be obtained by survey prior <br />to mining. <br />• At least two subsidence survey monuments should be installed at the center of two <br />adjacent sides of each well pad. The subsidence monuments may be surveyed by optical <br />or GPS devices. A baseline survey should be performed before development of the panel <br />hosting the well. These surveys should be performed to National Geodetic Survey (NGS) <br />Second Order Class II or better standards. <br />• Annual surveys should be conducted for the operating life of each gas well. <br />• If lateral displacements of more than 1 foot or tension cracks within 25 ft of the pad are <br />observed, investigation into well integrity should be undertaken. <br />• Underground indications of protective pillar failure should be noted and a determination <br />made regarding well integrity and possible mitigation. <br />• Structural anomalies reported by the surface owner(s) will be investigated. <br />4.1.3 Worst Possible Consequences of Damage to Gas Wells <br />In case the gas wells experience strains exceeding their yielding limit, they could bend, <br />crack, or rupture, leading to disruption in gas production. <br />4.1.4 Gas Well Damage Mitigation Plan <br />In case monitoring data indicates damage or potential for damage to the gas wells, the <br />following mitigation plan should be adopted. <br />• Appropriate personnel at mine and regulatory authorities, as well as the owner(s) of the <br />gas well, should be informed in case anomalies are observed that may indicate a damaged <br />well. <br />• The mining plan should be re- evaluated to ensure that operations will not further damage <br />the well. <br />Some of the gas wells may have a pump jack installed on the wellhead. The subsidence <br />control, monitoring, and mitigation plan for a gas well encompasses the guidelines for mining in <br />the vicinity of a structure such as a pump jack. <br />4.2 Gas Pipelines <br />4.2.1 Gas Pipeline Subsidence Control Plan <br />It is anticipated that pipelines can be undermined using development -only workings <br />without impacting the pipelines. Given the anticipated range of cover depths and width of <br />entries and crosscuts, it is highly unlikely that any perceptible surface deformation will occur. <br />However, the pipeline owner(s) should be notified prior to commencement of room - and - pillar <br />operations under those particular pipelines. <br />Agapito Associates, Inc. <br />