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<br /> 1 <br /> <br /> <br />t <br /> <br /> 1 INTRODUCTION <br />' 1.1 Background <br /> This monitoring plan was prepared by Water Management Consultants, Inc. on behalf of <br />' Homestake Mining Company as part of the Bulldog Mine Reclamation project. The Bulldog Mine <br /> is located in Mineral County, Colorado, approximately 0.5 miles northwest of Creede. The Bulldog <br /> mine and vicinity are shown in Figure 1.1. <br />' <br /> The mining operations at the Bulldog Mine ended in 1986. Reclamation including demolition and <br /> removal of mine buildings, closure of tailing facilities, re-grading and re-vegetating the waste <br />' dumps, and closure of the 9360 Adit and 9700 Adit was completed by 1992. Closure of the 9360 <br /> Adit included cribbing, structural support, and a bentonite plug to prevent possible seepage from <br /> the adit. <br />' 9360 P <br />f <br />h <br /> During Spring 1995, which was abnormally wet, seepage was observed outside o <br />t <br />e <br />ortal <br /> area. In response, Homestake Mining Company reopened the 9360 Portal during Fall 1996 to <br /> inspect the adit plug and evaluate water conditions. Subsequently, in preparation for 1997 Spring <br />' runoff, a water management system was implemented to handle the expected seepage from the <br /> adit. The Division of Minerals and Geology (DMG) approved system, consisted of a settling basin <br />' and a spray evaporation system (Technical Revision No. 4). <br /> In Spring 1997, the first significant flows were observed and the seepage was handled <br /> successfully by the water management system. In September 1997 the original adit plug was <br /> removed to further evaluate conditions in the adit. The water management system was <br /> subsequently upgraded to include an infiltration trench, approved by the DMG, for handling <br />t discharge during freezing conditions when the spray evaporation system was not effective <br />(Technical Revision No <br />6) <br /> . <br />. <br />' Reopening of the adit indicated that the condition of the adit is very poor and it was anticipated <br />that stable and safe conditions could not be maintained in the adit. Therefore, adit reopening <br />activities were stopped prior to Spring 1998. A design for a concrete adit plug was subsequently <br />finalized and plug construction began in March 1998. <br /> <br /> <br />1 <br />