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Ken Coal Company <br />Marr Mine Drill Holes and Water Monitoring Well Reclamation <br />Recommended Abandonment Procedures <br />The following pazagraphs reflect the current understanding of the obligation of Ken Coal <br />Company to permanently plug and abandon boreholes and water monitoring wells that were utilized <br />for the Man Mine project. The Matt Mine was initiated through the issuance of a Coal Exploration <br />License Serial No. C-28056 on May 1, 1979 to Ken Coal Company (Ken) from the Department of the <br />Interior, Bureau of Land Management. <br />Based upon the reviewed information there appear to be approximately 45 wells (boreholes) for <br />which Kerr is responsible for properly plugging and abandoning. There are additional wells where the <br />ownership is uncertain and might add additional wells to the Ken list. Also, there is potential for some <br />of the wells to be utilized as water wells or kept as monitoring wells. <br />When the license was issued in 1979 an attachment (Exhibit "A") to the letter depicted a <br />generic drill hole abandonment diagram presented by the U.S.G.S. The diagram depicts a borehole <br />void of any type of pipe. The boreholes at Man Mine are not reflective of the generic diagram. The <br />main objective of the diagram is to display the cement plugs that are necessary to isolate coal beds and <br />potential aquifers. The proposed procedures that aze presented below aze designed to abandon the <br />wells to reflect the 1979 abandonment diagram as they pertain to isolating coal beds and aquifers. The <br />following procedures will isolate the coal beds (or aquifer) even though pipe will remain in the hole. <br />For the purpose of this analysis and abandonment recommendation the wells have been put into <br />three main categories. The first category consists of wells that aze greater than 400 feet deep. Most of <br />these wells have 2-inch plastic pipe inserted to total depth. Most wells have slotted pipe in the bottom <br />of the hole for approximately 100 feet. One of these wells has slotted pipe for the entire interval. One <br />of these deep wells has only 180 feet of pipe in a hole that was drilled to 500 feet. This well, #79-1, <br />will have a modified abandonment procedure as compared to the other wells. The second category of <br />wells range in depth from approximately 100 feet to 360 feet. The majority of these wells have 2-inch <br />plastic pipe inserted over the entire depth of the well. Most of these wells have slotted pipe over the <br />entire well. Some of the wells have 4-inch or 6-inch plastic pipe and a couple of wells have steel pipe. <br />The third category consists of shallow wells that range in depth from approximately 14 to 50 feet. <br />Based upon the lithology, logs only one well in this category penetrated a coal seam. Some of these <br />wells made water and some did not, A cement plug in these wells is more than adequate for proper <br />abandonment. The vast majority of these wells have 2-inch plastic pipe over the entire depth. <br />The following procedures are designed to adequately and permanently abandon the boreholes <br />for which Kerr is responsible. The general procedure may have to be modified in the event <br />circumstances dictate. <br />Steo 1 (Identify cement collazs) <br />It is believed that most of the wells have a cement collar around the pipe of no more than 10 feet in <br />thickness near the surface. All wells should be inspected for the presence or absence of this cement <br />collaz. <br />