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sampling results the following elements will be deleted from future groundwater sampling <br /> events: aluminum, ammonia, antimony, beryllium, boron, cadmium, cobalt, cyanide, lead, <br /> mercury, molybdenum, silver, thallium, uranium, and vanadium. <br /> 8.0 CONCEPTUAL HYDROLOGIC SITE MODEL- MINE INFLUENCE <br /> HYDROGEOLOGIC SITE MODEL <br /> The following is a summary of the results of a conceptual mine site flow modeling for the May <br /> Day Idaho mine complex. The May Day mine drainage has been confirmed by observation, <br /> whereas, the Idaho Mine drainage has not been field validated because of limited access to the <br /> underground workings. As previously discussed, the major controls to groundwater flow are <br /> geologic fractures, low permeable sedimentary aquifers and historic underground mine workings. <br /> Historic mine workings have partially drained the May Day and Idaho Mines, as briefly <br /> discussed in the following sections. <br /> 8.1 May Day Mine Property <br /> Figure 7 is a conceptual block model of the geologic and mine workings associated with the <br /> overall mine site. The block model illustrates the location of adits, winzes, cross cuts, drifts, <br /> faults, veins, geologic formations and structure. Figure 8 illustrates the underground flow <br /> direction of May Day No. 1. The monitoring well proximal to the May Day No. 1 portal (MD-1) <br /> appears to suggest static water levels respond to thunderstorms and snow melt infiltrating into <br /> underground workings. The aquifer adjacent to the May Day No. 1 workings exhibit low <br /> permeability (well yields are less than 2.5 gpm) and the underground workings are essentially <br /> dry throughout the year, (Gonzales, 2010). The May Day No. 1 Adit and mine workings are <br /> above 9,300 feet asl and are approximately 100 feet above the static water level identified in <br /> May Day No. 2 (MD-2) water monitoring well. <br /> The flow in the May Day No. 2 mine workings is approximately 45 feet below the May Day No. <br /> 2 workings is illustrated on Figure 9. Water identified in May Day No. 2 mine workings appears <br /> to originate from fractures and very low flows from the adjacent low permeable geologic <br /> sandstone and shale. The May Day No. 2 mine adit drainage conceptual groundwater flow path <br /> is illustrated on Figure 9 (Gonzales, 2010). Water accumulation in old workings appears to <br /> collect during spring melt runoff from fractures from May Day No.1 and No. 2 mine workings. <br /> The maximum flow rate that that has been observed by the Operator from the May Day No. 2 <br /> adit is less than 0.5 gallons per minute. <br /> 8.2 Idaho Mine Property <br /> The flow in the Idaho mine workings is conceptually illustrated on Figure 10. As previously <br /> discussed related to the May Day Mine workings, groundwater in the Idaho mine workings <br /> appears to be related to fractures and direct recharge within the Little Deadwood Gulch drainage. <br /> Flows from the Idaho (seep) appears to be proportional to the flows observed in Little Deadwood <br /> Gulch and to water that may exist in the underground mine workings. Water samples obtained <br /> May Day Idaho Mine Complex <br /> M-1981-185 <br /> January 19, 2017 <br /> Page I - 14- <br />