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HomeMy WebLinkAbout20091252.tiff• • ENERGY COMPANY P.O. BOX 467 GOLDEN, COLORADO 80402 May IS, 2009 City Clerk's Office Keenesburg Town Hall 140 South Main Keenesburg, Colorado 80643 Weld County Clerk & Recorder P.O. Box 459 Greeley, Colorado 80632 Re: Technical Revision No. 40 -- Proposed Modify Final Reclamation Contours Keenesburg Mine Keenesburg, Colorado Ladies and Gentlemen: In accordance with the rules and regulations governing coal mining and reclamation operations in the State of Colorado, public notice and a public review period is to be provided when a Technical Revision to an existing Permit is proposed. Coors Energy Company has submitted its Technical Revision No. 40, requesting approval of a change to the approved final reclamation contours across the long-term spoil area (only), at the Keenesburg Mine near Keenesburg, Colorado. This change, if approved, will provide for a better blend of reclamation with the undisturbed lands, and will insure adequate material for final cover. Notice has been placed in the local newspaper closest to the operations site (the Ft. Lupton Press) and a copy of the proposed Technical Revision is enclosed. Would you please place this letter and the enclosed documents in a location where they can be made available to members of the public who might wish to review the contents. Thank you for your assistance. Manager, Energy Services • enclosures lU3L[c E ttZ2.) 7)4i-1 2009-1252 PUBLIC NOTICE • Coors Energy Company, P.O. Box 467, Golden, CO 80402, (303) 277- 3455, has applied to the Colorado Division of Reclamation, Mining & Safety (DRMS) for approval of a technical revision to modify final reclamation contours across the long term spoil area of the Keenesburg Mine site. The intent of the revision is to better blend reclaimed land contours with previously undisturbed ground while insuring adequate material for final cover. Coors Energy Company owns and operates the Keenesburg Mine under DRMS Permit C-1981-028. The Keenesburg Mine is located 7 miles north of Keenesburg, Colorado, and is accessed by Weld County Road 59. The USGS 7.5 -minute quadrangle maps "Klug Ranch" and "Tampa" contain the described operation. The permitted area is portions of Sections 25 and 36, T3N- R64W, 6th Principal Meridian, Weld County, Colorado. A more exact description of the permit boundary, included herein by reference, may be found in the Permit Application Package under Legal Description. • • Copies of the application may be viewed at the Town Hall, 140 S. Main, Keenesburg, Colorado; at the Weld County Clerk and Recorder's Office, 1402 N. 17th Ave., Greeley, Colorado; and at the Colorado Division of Reclamation, Mining & Safety, 1313 Sherman Street, Room 215, Denver, Colorado 80203, (303) 866-3567. Copies of the Permit Application Package are on file at the Keenesburg Mine Site and at the Colorado Division of Reclamation, Mining & Safety. All comments, objections, and requests must be submitted in writing to the Colorado Division of Reclamation, Mining & Safety at the above address. The public comment period extends for ten days following the date of publication of this notice. Published in the Ft. Lupton Press, on May ,a(L, 2009. • • • illi ENERGY COMPANY P.O. BOX 467 GOLDEN, COLORADO 80402 April 22, 2009 Ms. Janet Binns Division of Reclamation, Mining & Safety Department of Natural Resources 1313 Sherman Street, Room 215 Denver, Colorado 80203 Re: Technical Revision No 40 Modification of Final Contours — Long Term Spoil Area Dear Ms. Binns: Coors Energy Company (CEC) is requesting consideration by the Colorado Division of Reclamation Mining and Safety (DRMS) for a Technical Revision to Permit C-1981-028. The effect of this Technical Revision (TR) will be to modify the final contour over the Long Term Spoil Area (LTSA), only. The submittal is offered following lengthy discussion and review of the material balance across the LTSA, the receipt of recently updated site -life calculations, and general grading observations as portions of the LTSA were re -contoured to match the advance of the B -Pit fill activity. With the earlier processing and approval of Technical Revision No. 34, CEC was attempting to address what, at the time was considered to be an amount of material in excess of the reclamation requirements across the LTSA. CEC subsequently made a change in engineering support services, and this change led to significant advancements in mapping support. The increased reliability and repeatability of the data, has convinced CEC that while the earlier change was in the right direction, it was too extreme, resulting in a higher than necessary relief configuration across the LTSA, and a potential shortage of material for the effective final cover of B -Pit. Through its submittal of this Technical Revision 40, CEC is asking for DRMS concurrence with a reduction in the impact of the previous TR; to increase and insure there is an adequate amount of spoil material for B -Pit final cover, and to accomplish this without significantly altering (by less than one foot, on average) the final contour across the LTSA. We have enclosed, as supporting documentation, (3 copies each of) a summary page for Technical Revision 40, an evaluation by American Environmental Consulting LLC, consultant to • • • CEC, updated maps for reference and for replacement (specifically Plate 2) in the Permit, and the DRMS Application Form. Included also is a proposed notice for publication. This notice will be placed in the local newspaper as soon as CEC receives concurrence from DRMS as to the format and content. Copies of the Technical Revision application will be delivered to the Keenesburg Town Hall and to the Weld County Clerk and Recorder's office for public access and review once approval is received and at the time the notice is published. CEC believes that the documentation herein submitted is complete and sufficient for the processing of this Technical Revision No. 40. However, should there be questions, please contact us at 303 277-3455. Since Donald W. Mac onald Manager, Energy Services . COLORADO DIVISION OF RECLAMATION, MINING AND SAFETY 1313 Sherman Street, Room 215, Denver, Colorado 80203, (303) 866-3567 APPLICATION FORM FOR A REVISION TO A COAL MINING AND RECLAMATION PERMIT This form must be completed and submitted with all requests for minor revisions, as defined in Rule 1.04(73), technical revisions, as defined in Rule 1.04(136), and permit revisions, as defined in Rule 1.04(90). All revisions are to address the requirements of Rule 2.08.4. Three (3) copies of the revision, including maps, must be submitted in order for it to be complete. All revisions are to be formatted so they can be inserted into the permit to replace the revised sections, maps, tables and/or figures, with a revised table of contents, if necessary. The revision submittal date should be printed in the lower right corner of each revision page. A cover letter to the revision should explain the nature of the revision and reference the specific permit sections being revised. For federal mines, a copy of the revision application must be submitted to all agencies on the federal mailing list (except OSM) at the same time the application is submitted to the Division, and proof of distribution must be submitted to the Division along with the application. Copies of revision pages modified during the review process must be distributed in the same manner, along with proof of distribution. Proof of distribution must be submitted prior to implementation of the revision. Permit No.: C - 1981 - 028 Date: 04 / 22 / 2009 Permittee: Coors Energy Company Street: P.O. Box 467 City: Golden State: CO Zip Code: 80402 _ 0467 Brief Description of Revision: Modify Final Reclamation Contours - Long Term Spoil Area Public Notice Attached: Yes X No _ (Required for PRs and TRs) Bond Increase: Yes _ No a Federal _ Non -Federal X Mine Proposed Change in: Permit Area - Disturbed (+/-) _ _ Permit (+/-) Affected (+/-) Mineral Ownership - Mineral Private (+/-) _ Mineral Federal (+/-) _ 0 . 0 Acres _0. 0 Acres 0 . A Acres 0 . 0 Acres Mineral State (+/-) _ _ 0 .0 Acres 0 . 0 Acres Surface Ownership - Private Land (+/-) _ _ 0 .0 Acres Federal Land (+/-)_ _ 0 0 Acres State Land (+/-) _ _ 0 .0 Acres • • • TECHNICAL REVISION NO. 40 MODIFICATION OF THE RECLAMATION CONTOURS ACROSS THE LONG-TERM SPOIL AREA COORS ENERGY COMPANY PERMIT NO. C-1981-028 In submitting this Technical Revision No. 40, Coors Energy Company (CEC) seeks to modify the final contour over the area known as the Long Term Spoil Area (LTSA). This area, identified in Appendix Q -1 of the Keenesburg Mine Permit, Permit Number C-1981-028 (the "Permit"), has been the source of material for both the intermediate and final cover of ash in the ash disposal pits ("A" & “B"). The necessity for this permit modification stems from a revised engineering evaluation of the remaining versus the required overburden (spoil materials from the LTSA) volumes. The evaluation was initiated by American Environmental Consulting, LLC (AEC). This evaluation has been relined over the past few years as the annual topographic mapping has been completed in greater detail. The final determination is that the LTSA, as it is currently configured, has a shortfall of approximately 58,098 bank cubic yards (bcy) of overburden material necessary to complete the reclamation work in B -Pit. Since Section 2.05.4 of the Permit indicates that "major disturbed areas will be returned to their approximate original contour", CEC proposes that the approximate original contour be modified across the I,TSA to better meet the soil cover requirements while also blending to the existing perimeter contours to remain consistent with the drainage plan. When viewed across the entire acreage encompassed by the Permit, CEC believes that these contour changes are consistent with the intent of the term 'approximate-, as used therein. Submitted with this application are copies (3 each) of the following: Reclamation Contour and Drainage Plan Map - as Revised: This is Appendix Q -I to the Permit, and is updated each year in the Annual Hydrology and Reclamation Report (AHR Report). Letter dated 4/7/2008 from AEC to CEC describing the evaluation, and providing the proposal with respect to the LTSA. CEC is not seeking an adjustment to the bonding amounts with this Technical Revision since the lands subject to this proposed revision are already included in the calculation of "total area remaining to he reclaimed (2008 Al IR Report. page 77). No new mining activity is proposed by this Technical Revision. Further, the activities proposed by this Technical Revision No. 40 require no placement of dredge or till material, or any excavation associated with a dredged or fill project. either temporary or permanent, in waters of the United States. The Division's approval of this Technical Revision No. 40 to modify the final contour over the Long Term Spoil Area, is hereby requested. • • • AEC AMERICAN ENVIRONMENTAL CONSULTING, LLC April 7, 2009 Mr. Donald MacDonald Manager, Energy Services Coors Energy Company P.O. Box 467 Golden, Colorado 80402 Re: Evaluation of Remaining and Required Reclamation Overburden Volumes Proposed Technical Revision to Approximate Original Contour Coors Energy Company-Keenesburg Mine Facility, Permit No. C-1981-028 Dear Mr. MacDonald: Coors Energy Company (CEC) has contracted American Environmental Consulting, LLC (AEC) to provide engineering consulting services for the Keenesburg Mine Facility located in Weld County, Colorado (facility). This letter report proposes a revision to the approved contours in the long-term spoil area (LTSA). The approximate original contours (AOC) were modified by Technical Revision 34, dated November 22, 2002 from CEC to the Division of Minerals and Geology. Since that time, further refinements of the topographic measurements and volume calculations has shown there to be a need to prepare a technical revision to these contours to result in additional overburden material for use in reclamation of the B -Pit and for drainage design purposes. The remaining and required LTSA overburden volumes are summarized below: Current Calculated Remaining Overburden Volume (265,372 bey): The current remaining LTSA overburden volume was evaluated using the following surfaces: 1) 2008 surface topography of the LTSA. and 2) LTSA bottom of topsand. The bottom of topsand, or top of final overburden surface, is fifteen inches below the approximate original contour (AOC) as defined in the facility permit (Permit No. C-1981-028). The LTSA contains approximately 265,372 bank cubic yards (hey) of overburden available for reclamation activities. Current Required LTSA Soil Volume (323,470 bey): The required LISA overburden volume was evaluated based on the B -Pit final and periodic cover volumes. The required overburden volume for the final B -Pit cover (6 -feet thick) was evaluated using the following surfaces: I ) B - Pit top of ash surface and 2) B -Pit bottom of topsand surface. 'lie B -Pit final cover overburden volume is approximately 217,648 bey. Approximately 9,688 hey of overburden is used annually as periodic cover in B -Pit based on an average of the recent cover volume usage. It is currently anticipated that ash disposal operations will continue for another 11.8 years resulting in a required overburden volume of 105.822 bey for periodic cover. Therefore, the total required I.TSA soil volume is estimated to be approximately 323,470 bey. There is a resulting shortfall of approximately 58,098 hey in the volume of soil available versus the volume of soil required using the contours approved as per Technical Revision 34. In order to balance the remaining and required LISA overburden volumes. AEC proposes slightly modifying the AOC in the LISA area as shown on the attached contour map. On average. we propose an additional 0.88 loot excavation over the LISA area although the actual excavation 6885 South Marshall St., Suite 3, Littleton, CO 80128 phone 303-948-7733 fax 303-948-7739 fir oh.%fro,,Greene/L(I__00Stecfinical rev, .mowlerhnical r errwoi: V!(' letter err 4 1009 Technical Revision to Reclamation Contours Coors Energy Keenesburg Mine Pane "1of2 April 7, 2009 will be greater in some areas than others. This contour change will result in a useable LISA soils volume of approximately 367,400 bcy (a slight excess of LISA soils of 43,930 hey) and is sufficient to complete the reclamation activities in the B -Pit. This "technical Revision is consistent with the facility Reclamation Plan (Section 2.05.4 of the permit) because the LISA area will be returned to its "approximate original contours". Additionally. the permit reclamation plan states: "if the long-term spoil pile should become inactive or if both 4- and 13 -Pits were to he completely reclaimed before the long-term spoil pile could be completely utilized, the remaining long-term spoil area soils will be graded and tied into the undisturbed natural terrain, and then scarified, topsanded, fertilized and revegetated." Based on this approach, AEC has revised the facility Reclamation Contour and Drainage Plan map (Appendix Q -I of the Permit and Annual Hydrology & Reclamation Report [AHRI). In general, the attached revised permit drawing (Plate 1) shows the proposed AOC modified from the currently -permitted AOC in the LISA area to excavate additional soils across the area while maintaining the drainage patterns to meet the goal of the reclamation plan which is to promote positive surface water drainage away from both the A- and B -Pits. Plate 2 (for substitution as Appendix Q-1 in the Permit) is the modified drawing with only the proposed contours. The revised AOC elevation contours were developed to minimize potential impact to the current drainage plan and allow drainage from the LISA to the permanent west perimeter ditch and then to the permanent Sediment Pond 2. The proposed AOC reflects fifteen (15) inches of topsand to be placed above the overburden as final cover in the LTSA. There are no contour changes over the B -Pit area. Thank you and if you have any questions regarding this letter, please contact me at 303-948- 7733. Respectfully. AMERICAN ENVIRONMENTAL CONSULTING, LLC Curtis . Ahrendsen Project Manager Attachments: Revised Reclamation Contour and Drainage Maps (Appendix Q -I ) AEC pi ow( t.‘ nertri100k irchnlcul revivionhtcln,unl rrvieiot.1O letter rev 2009 LARGE MAPS AVAILABLE FOR VIEWING AT THE CLERK TO THE BOARD'S OFFICE, IN THE PUBLIC REVIEW FILE. Hello