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Monument Dam: <br />Photographed landslides to north and south of dam <br />either by air or other method, annually. <br /> Map 2 of the reports indicates E-1 longwall mining approached within one <br />Surveyed monuments on dam and on north, south, mile of Monument Dam during the report period; therefore, monthly <br />and east edges of reservoir, premining through monitoring and weekly visual inspections were required. Visual <br />postmining. Frequency: Dam axis either quarterly inspections met the requirement (as shown by copies of the inspection <br />or annually (conflicting text in permit), then monthly forms in the report), but survey data were not included in Appendix C of <br />when E-seam longwall mining is within 1 mile the report; therefore, satisfaction of the survey requirement could not be <br />(frequency on reservoir edges is unspecified). determined. Appendix C also did not contain graphs of movement of the <br /> See dam. <br />Visually inspected monument transects (dam and <br />reservoir edges) for cracks, 1 month through 2 to 3 comment A seismic monitoring report has not yet been submitted for the 1" or 2°d <br />months after mining in E-1 or E-12. (Frequency not quarters of 2010. (The DRMS previously received and reviewed the <br />specified in permit.) 4`h quarter 2009 seismic monitoring report.) <br />Measured water levels in dam crest piezometers, Appendix D contains the required annual photos of the landslides to the <br />monthly Apr - Oct, when accessible.: north and south of the dam. <br />Visually inspected dam structure for cracks, weekly <br />while longwall mining is within 1 mile. <br />Resurveyed monuments on dam and reservoir edges <br />ASAP when seismic event has PGA >0.15 g. <br />Conducted sufficient post- <br />mining monitoring to <br />verify subsidence <br />rediction <br />2.05.6(6I(i))(F) <br />Yes The traverses in the Spring 2010 study included observations of new and previously identified <br />subsidence features. The report describes changes to the previously existing features that have <br /> <br />occurred since previous visual inspections. <br /> The Spring 2010 report describes recent surface subsidence activity, including: a) lessening of <br /> rockfall and slabbing in the West Flatiron area, b) no new subsidence features in the Box <br /> Canyon area, c) rockfall has largely ceased on the east side of Sylvester Gulch since the Fall <br />Accurately predicted 2.05.6(6)(d)(i) Yes 2008 report, d) mining induced cracks in soft material at methane drainage wells pads (some <br />subsidence. features have been regraded), e) complete or partial healing of some of the subsidence cracks <br /> found during previous reporting periods. These impacts are consistent with the subsidence <br /> prediction in the permit application. <br />Prevented imminent or <br />actual material damage or <br />diminution of use of 2.05.6(6)(d)(i) Yes <br />renewable resource lands <br />or structures