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,~ iG~~ <br />SENECA <br />Coal Company Senec <br />Jnly 26, 2007 JUL 3 0 2007 <br />Mr. Daniel Mathews Division of Reclamation, <br />Division of Reclamation, Mining and Safety Mining and Safety <br />1313 Sherman Street, Room 21 ~ <br />Denver, CO 80203-2273 <br />RE: Seneca II-W Mine Permit C-82-057 <br />W24 Seties Well Abandonment Procedure <br />Dear Mr. Mathews, <br />In 2007, Seneca Coal Company (SCC) will attempt to abandon the W24 series monitoring wells in <br />the II-W South Axea that were damaged by a landslide in 2003. Several attempts were previously <br />made to abandon these wells, all of which have failed. Details of the previous attempts are <br />summarized in a Jul}' 14, 2006 letter addressed to btike Boulay, of which you were copied. In that <br />letter, SCC requested a variance of normal abandonment procedures. <br />In a letter dated December 12, 2006, Dave McElhaney of the Division of Water Resources outlined <br />their recommended abandonment procedure. A cop}' of that letter is attached. SCC will attempt to <br />follow this procedure as closely as possible, conditions allowing. Regular cement will be used to grout <br />the wells. \~ithin 60 days of abandonment, well abandonment reports will be sent to you and the <br />Division of Water Resources. Also, a minor revision will be submitted to correct the language on <br />page 11 of Tab 15, which addresses the abandonment of these wells. Also in that revision, a <br />commitment to monitor annually the water discharging from the french drain (aka, Spring 50) will be <br />made. <br />The french drain that was installed on October 7, 2003, was about 50 feet long, 20 feet wide and 3 <br />feet deep. One and a half inch diameter gravel was used. An erosion blanket was placed on top of <br />[he rock, and then backfilled with dirt. "Phis french drain will be left in place after the well <br />abandonment, and will be left so that water can flow freely to the surface. SCC recommends that the <br />no development (ic, buildings or roads) be place on top of the french drain, but the area surrounding <br />the french drain should not be affected. <br />Discharge from the french drain was monitored twice in 2006. The water was flowing at a rate of 19 <br />gallons per minute. Review of the data indicates that the water is suitable for agricultural use, <br />compared to CDPFIF_ surface water agricultural standard. Since the creation of the French drain, no <br />esceedances of NPDES effluent standards have occurred downstream at Pond 016. <br />Should you ox other members of the Division have questions, please do not hesitate to contact me at <br />(970) 276-5209. <br />Sincerely, 9~ <br />~~~~ <br />Dennis Jones <br />Hydrologist I <br />Seneca Coal Company <br />cc Mike Boulay, CDRbtS, Grand Junction <br />Daniel Mathews, CDRMS, Grand Junction <br />Seneca Coal Company • P.O. Box 670 • Hayden, Colorado 81639 <br />