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BRL conducted baseline geotechnical investigations on the Bruce Park Dam and environs in <br />2000 and 2001. Further, BRL commissioned amining-induced seismicity study for the Bruce <br />Park dam that was submitted to the Division and the GMUG in 2002. The GMUG acknowledges <br />BRLs efforts to fulfill stipulation (J)(B) by conducting these studies, however the following <br />questions remain: <br />1) In the seismicity study, assumptions for calculating peak particle velocity were based <br />on a distance of 0.75 km (just less than 0.5 miles) between mining and the dam. BRLs <br />PR-10 proposal projects the extent of subsidence associated with panel B13 to extend to <br />about 1,490 feet (0.28 miles) of the dam. We request BRL provide additional information <br />on the distance between the closest panel margins and the dam, and clarify if the <br />seismicity report distance of 0.75 km was related to the edge of expected subsidence or to <br />actual panel location. We would also clarification on whether there would be cumulative <br />weakening effects on the dam from a series of low magnitude events in the area (see item <br />2 below). <br />2) The GMUG acknowledges BRLs efforts to install the seismic monitoring system as <br />required in this stipulation. However, the PR-10 package does not Include results of this <br />monitoring. We request that BRL provide the data available to date so that potential risk <br />to the dam can be evaluated based on actual data and expected magnitude of mining- <br />induced seismic events and frequency pertinent to the local area. <br />3) It is unclear if the geotechnical and seismicity studies and seismic monitoring system <br />had been developed in cooperation with the State Engineer's O~ce as required in the <br />stipulation. We request that BRL provide information on whether this has been fulfilled. <br />Pertaining to federal coal lease stipulation (f)(C), we need to point out that the Bruce Park dam <br />and reservoir are facilities under special use permit with the Forest Service, and hence are <br />subject toprotections of the stipulation. We would like to review and discuss any contingency <br />and mitigation plans. The GMUG is also dealing with similar issues elsewhere on the forest. <br />Further, we have heard from the special use permittee that they have specific concerns related to <br />this PR, therefore we will need the opportunity to discuss the concerns with the special use <br />permittee, BRL, the State Engineer's Office and the Division. <br />We have also identified the following comments in the revised text pages: <br />Page 2.04-32, discussion on Dove Gulch. The GMUG disagrees that Dove Gulch is an <br />ephemeral drainage, based on our specialists knowledge of the area, this drainage is best <br />described as intermittent. We request this change be made in BRLs permit. <br />Page 2.05-104, Section (b)(i)(A): The pre-mining land use for the national forest system lands in <br />BRLs permit are described in the GMUG Land and Resource Management Plan as managed for <br />`wildlife habitat management for one or more Forest Service management indicator species <br />(MIS). Semi-primitive -non motorized, semi-primitive motorized, and roaded natural recreation <br />opportunities aze provided. Livestock grazing and vegetation treatments are allowable.' We <br />appreciate this change being made to BRLs permit. <br />