GENERAL32987 - Laserfiche WebLink

Home Browse Search

//n` r~' A -11- ~, ~G~,J~~ Empire Energy Corporation has proposed to limit mining to partial (509L) extraction beneath the Yampa River and the Big Bottom area, As a result, the applicant indicates that no subsidence is planned or expected and that the alluvial valley floor's capability for flood irrigation would not be affected. However, in the event subsidence were to occur, a mitigative plan has been proposed. Empire Energy Corporation has committed to repairing and regrading areas overlying the Eagle No. 9 Mine workings should subsidence create ponding in irrigation ditches and in fields (page IV-194a of the permit application). The company has also committed to reseeding those areas which may be regraded. Thus the applicant will be able to restore the essential hydrologic functions, flood irrigability, of the Yampa River/Big Bottom AVF and also maintain the pre-mining productivity of the AVF. If the worst case subsidence were to occur within the Big Bottom alluvial valley floor, it could cause disruption of the essential hydrologic function. To confirm the extent of subsidence, a network of subsidence survey monuments is proposed above the First West submain area of the Eagle No. 9 Mine (labeled as Monument Series H and I on Map IV-7). Additional subsidence monitoring is warranted to verify the company's subsidence predictions over a development main, and also to trigger the mitigative measures proposed by the company to prevent material damage to the alluvial valley floor (page IV-194a of the application). To insure that the company reestablishes the essential hydrologic function (flood irrigability) of the Big Bottom alluvial valley floor, and to prevent material damage (reduced crop productivity) of a renewable resource land, the following stipulations are required to find the applicant in compliance with Rules 4.28 and 2.05.6(6)(c). StiDUlation No. 26 THE DIVISION DIRECTS EMPIRE ENERGY CORPORATION TO INSTALL AND MONITOR ONE ADDITIONAL SET OF SURVEY MONUMENTS OVER A SET OF DEVELOPMENT MAINS AT THE EAGLE N0, 9 MINE. THE MONUMENT SERIES OVER THE DEVELOPMENT MAINS AND MONUMENT SERIES H AND I SHALL BE INSTALLED WITHIN SIX (6) MONTHS OF THE PERMIT ISSUANCE. THE SURVEY MONUMENTS SHALL BE PLACED OVER MINE AREAS WHICH WILL BE MINED WITHIN TWELVE (12) MONTHS OF THE TIME THAT MINING BEGINS. TWO MONTHLY MEASUREMENTS OF THE SURVEY MONUMENT ELEVATIONS SHALL BE MADE PRIOR TO UNDERMINING THE SETS OF SURVEY MONUMENTS. ONE MEASUREMENT OF THE SURVEY MONUMENT ELEVATIONS SHALL BE MADE IMMEDIATELY AFTER DRIVING THE DEVELOPMENT MAINS AND AFTER ROOM AND PILLAR ADVANCE. ALL SUBSEQUENT MONITORING OF SURVEY MONUMENT ELEVATIONS SHALL BE MADE QUARTERLY. ALL DATA FROM THIS SUBSIDENCE MONITORING SHALL BE SUBMITTED IN THE COMPANY'S QUARTERLY SUBSIDENCE REPORT.