Nevada Copper Corp. is pleased to announce that it achieved a major milestone at its Pumpkin Hollow project by way of reaching the 1,900 foot main haulage level at its 24-foot diameter concrete-lined production sized shaft.
A concrete-lined production shaft to the level of the main workings further de-risks the Pumpkin Hollow project and was defined as project milestone in early 2011. During 2012, after the official ground breaking in February, shaft related construction activities included: shaft foundation ("sub-collar"); "pre-sink" to 99 feet; installation of a production-sized hoist and control room; erection of a permanent head-frame; plus related surface facilities. Early in 2012, management made a decision to forego a temporary sinking hoist arrangement and take the additional time to purchase and construct a production-sized hoist, hoist control room and erect a permanent head-frame. This decision is expected to accelerate future project construction activities.
In May 2013 with all facilities in place and operational with the "pre-sink" completed, shaft sinking resumed below 99 feet. During progress of the shaft towards the 1,900 foot main haulage level, an effective dewatering program was implemented. This consisted of drilling two fully commissioned dewatering wells (1,500 and 2,070 feet deep), with water disposal by way of eight permitted rapid infiltration basins, and summer agriculture irrigation.
While the 1,900 foot level milestone was delayed from our initial estimate, it was delivered within an acceptable timeframe considering the Company's decision to purchase a production-sized hoist and erect a permanent head frame.
Nevada Copper will now move forward with approximately 700 feet of lateral development on the 1,900 foot main haulage level and construction of drill stations for purposes of locating and expanding high grade ore to enhance an already high grade profile. The lateral development will also establish key work areas underground for future development, and provide for future access to the East ore zones. Drilling was suspended on the underground deposits in 2011 in view of the then-outlined proven and probable mineable reserves with a view of resuming drilling upon accessing the main haulage level. The current underground drilling program is expected to commence in April and will consist of 26,000 feet (7,900 meters) of drilling.
The shaft is currently within the host skarn related rocks where little or no water is reporting to the bench. Good ground conditions are expected for the lateral development work. As lateral development and drilling continues on the 1,900 level, the shaft will be deepened first to 2,050 and then to its final depth of 2,150 feet. At the 2,050 level, lateral development around the shaft will provide for a station and development to the west and north in Q3-2015. In addition, a temporary sump will be cut out at the level (which will be used for temporary storage, equipment safety bay, and eventually become the bottom of a waste pass). The lateral development work is the minimum necessary in order to continue sinking the remainder of the shaft, while still allowing for equipment delivery to the 2,050 level for future mine development.
Source: http://www.nevadacopper.com/