2018-10-05_REVISION - M2009076 - Laserfiche WebLink

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TECHNICAL REVISION NO. 5—Plant Modification HUKILL GULCH MILLSITE (DRMS Permit No. M-2009-076) Venture Resources, Inc. are terminated. While it is Venture's expressed intent to retain the structure"in place"at the conclusion of milling operations, Venture acknowledges that DRMS will require the provision of an incremental reclamation bond amount sufficient to cover costs associated with the equipment removal and restoration of the affected area. To that end,Venture has prepared the included incremental reclamation cost estimate to address mill structure demolition and site restoration(reclamation). It is anticipated that the planned plant modification will not only enhance gold recovery, but also result in the reduction (or elimination) of the potential for adverse environmental impact within the process plant operations area, and the downgradient tailing storage facility, due to the planned elimination of the froth flotation recovery circuit(and its associated process chemicals).Venture has,however,retained provision for lime addition(for purposes of pH control)in the revised process flow schematic. Venture will retain the current "approved" status (authorizing the utilization of froth flotation), in the event that it is later determined that froth flotation is necessary to achieve more economic or technically efficient gold recovery. To this end, sufficient space is being allocated within the footprint of the new structure to accommodate(potential)future reinstallation of the froth flotation equipment. Process areas within the new structure will be equipped with full perimeter spill containment, to include sloped floors and collection sumps. Venture acknowledges that the process plant area will continue to be considered an Environmental Protection Facility (EPF) and remain subject to the current Designated Mining Operation (DMO) status. Venture will accordingly update the Hukill Mill site's existing Stormwater Management Plan to reflect the incorporation of the proposed new structure. The existing facilities (i.e.,the current or pre-modification conditions) are depicted in Figure 1: Existing Process Plant Area Site Plan. The proposed process plant modification will affect a limited portion of the permit sub-area currently dedicated to the process plant facilities,as depicted in Figure 2:Proposed Mill Upgrade Site Plan. Milling: The trailer unit that currently houses the ball mill unit and gravity concentrating table will be removed from the site. A ball mill will be placed into the new, permanent structure(in conjunction with a new gravity recovery circuit). Gold Recovery: The trailer unit that currently houses the froth flotation equipment will be removed from the site. New Mill Structure: Venture proposes to construct a nominal 40 ft. x 50 ft. pre-engineered structure on a two-level concrete slab at the approximate same location as that currently occupied by the two (to-be- removed)trailer units that currently contain the ball mill and flotation/gravity circuits, respectively. The structure will be located immediately to the southeast of the established parking and incoming ore staging area. The nominal 50 ft. (longitudinal) dimension is to be oriented northwest to southeast. Crushed ore will enter(via covered conveyor)through the southeast end of the structure. 2