Tag Archives: Nevada Copper

Nevada Copper drafts in Dumas Mining as part of Pumpkin Hollow restart plan

Base metals, Mine operation news, Mining services, , , , , ,

Nevada Copper, in providing an update on restart and operational activities for its Pumpkin Hollow underground copper mine in Nevada, USA, has confirmed the appointment of Dumas Mining as its Capital Projects Construction contractor.

The company is currently targeting a mill restart in the September quarter with a quick ramp up to nameplate capacity by the end of 2023.

Back in June 2022, an unidentified weak rock structure was encountered in the main ramp to the East South Zone at the undeground mine. This, Nevada Copper says, restricted access to the company’s planned East South stoping zones. In response to this event, the company took steps to curtail operating activities while developing plans to address this issue.

In the latest update, Nevada Copper said it had a clear line of sight to full-scale production with a “simple and low-risk pathway to full-scale production” established.

Randy Buffington, President & CEO of Nevada Copper, stated: “Our Pumpkin Hollow team is focused on advancing the restart project quickly and safely. We are building on the momentum of the recent achievements by the underground crews as they have progressed through the dike structure and are advancing into the EN Zone in anticipation of the underground development contractor arriving on site and commencing development. The technical and leadership teams are in place and committed to executing this restart plan. We are targeting a mill restart in the third (September) quarter with a quick ramp up to nameplate capacity by the end of 2023.”

Development into the EN Zone has demonstrated that rock quality is consistent with its geotechnical model, which predicted competent ground within the EN Zone, and development is progressing at full round lengths and standard ground support, Nevada Copper says.

The company has awarded a contract for completion of capital projects to debottleneck restart of development and underground operations. This is where Dumas is involved with Nevada Copper signing a $12 million construction contract to complete critical capital projects including the coarse ore bin and installation of an underground jaw crusher, permanent dewatering system, vent shaft stripping and surface fans. Dumas, part of Stracon, is a full-service underground mining contractor providing mine construction, development, production mining, mine services and engineering early-stage projects through well-established operating mines throughout the Americas.

Nevada Copper says its operations team, meanwhile, continues to make rapid progress on all underground activities including mine development, hoisting, stope preparation and underground projects. It has completed the bid process for the development mining contractor and is in the final stages of negotiations for a unit rate contract with an “internationally recognised major mining services contractor”, it said.

Key components of the development contract include 72,000 ft (21,946 m) of lateral capital development over a 24-month contract period; delivery of full development stopes by the September quarter of 2023 to provide sufficient faces and stopes to restart and maintain nameplate milling operations (approximately 5,000 t/d); and Nevada Copper’s operating team will perform all stope mining starting in the September quarter.

Redpath to deliver Pumpkin Hollow ramp-up, Nevada Copper says

Base metals, Mine operation news, Mining services, , , , , , ,

Nevada Copper has engaged mining contractor Redpath USA to implement its ramp-up strategy for its underground copper mine at Pumpkin Hollow, in Nevada.

The company commenced production at the underground mine in December and is now entering into a new phase of development supporting its ongoing operations. It said it has “high confidence” in Redpath’s ability as a partner during the ramp-up to full commercial production in 2020.

Redpath replaces the previous mining contractor and will be the company’s principal underground mining contractor going forward, Nevada Copper said. “Redpath is a highly experienced mining contractor with experience of delivering complex projects both internationally and in Nevada, ahead of schedule and under budget,” it added.

Matt Gili, Chief Executive Officer of Nevada Copper, said: “Nevada Copper made the transition to producer in Q4 (December quarter) 2019 and we have developed a clear, straightforward strategy for ramping up our Pumpkin Hollow underground project to full commercial production. Redpath is considered throughout the mining industry as the partner of choice for production ramp up and we are excited to be working with them during this important period of growth.”

Nevada Copper has previously said it is focused on ramping up the mine, in Yerington, to reach nameplate capacity in the first half of 2020.

The 2017 prefeasibility study plan for the underground mine outlined a 5,000 t/d project able to produce some 50 MIb/y (22,680 t/y) of copper, 8,000 oz of gold and 150,000 oz of silver over a 13.5-year life at all-in sustaining costs of $1.96/Ib of copper. It also laid the foundations for a larger integrated project that includes open-pit development and could increase throughput to 70,000 t/d.

Nevada Copper ships first Pumpkin Hollow concentrate

Base metals, Mine operation news, Mineral project development, Mining services, Precious metals, , , , , ,

Following the start of production on December 16, Nevada Copper has shipped the first copper concentrate from its Pumpkin Hollow copper mine, in Nevada, USA.

Having reached these milestones, the company is now focused on ramping up the mine, in Yerington, to reach nameplate capacity in the first half of 2020.

The 2017 prefeasibility study plan for the underground mine outlined a 5,000 t/d project able to produce some 50 MIb/y (22,680 t/y) of copper, 8,000 oz of gold and 150,000 oz of silver over a 13.5-year life at all-in sustaining costs of $1.96/Ib of copper. It also laid the foundations for a larger integrated project that includes open-pit development and could increase throughput to 70,000 t/d.

Matt Gili, Chief Executive Officer of Nevada Copper, said: “Our first shipment of copper concentrate has left Pumpkin Hollow, representing another important milestone as we look forward to continuing our ramp-up to full commercial production in 2020.”

Both Cementation USA and Sedgman USA were involved in the Pumpkin Hollow build, with the former carrying out shaft sinking and underground mine development work and the latter completing the engineering, procurement and construction contract for the surface plant and infrastructure.

Golder and Sedgman outline Pumpkin Hollow open-pit potential for Nevada Copper

Base metals, Bulk handling, Comminution of minerals, Energy minerals, Metallurgy, Mineral processing, Mineral project development, Mining equipment, Mining project news, Precious metals, , , , ,

The preliminary economic assessment on Nevada Copper’s Pumpkin Hollow open-pit project has given the company food for thought, just as it starts construction on the underground mine.
Golder Associates and Sedgman Canada produced the PEA, which showed a 37,000 t/d (short) open-pit mine producing 80,286 t/y of payable copper at a C1 cash cost of $1.67/Ib (net of by-product credits) could be built for $592 million.

This plan is a departure from the 70,000 t/d (short) open-pit project outlined in 2013, which would have required $926 million of upfront capital and produced 85,900 t/y of copper over a 23-year mine life.

The latest PEA envisages an expansion to 70,000 t/d (short) in year eight of the mine, costing an additional $447 million, but would see higher-grade ore mined in the first five years of operation to increase the potential returns and decrease the amount of pre-stripping required.

Matt Gili, President and CEO of Nevada Copper, said: “The phased development approach…aligns with our strategy of pursuing optionality through low-capital intensity and staged production growth to generate shareholder returns. We have used this same margin-over-tonnes philosophy with the Pumpkin Hollow underground mine, which will be in production in 2019, and we are looking forward to the next steps in advancing the open-pit project.”

The Nevada Copper board signed off on the construction of the underground mine late last month.

Pumpkin Hollow Underground is expected to process 5,000 t/d and produce some 50 MIb/y (22,680 t/y) of copper over a 13.5-year life at all-in sustaining costs of $1.96/Ib.

The open-pit project, meanwhile, is envisaged as a conventional truck-and-shovel operation planned to use a combination of hydraulic and electric cable shovels and haul trucks.

The mining fleet includes 240 t class trucks, loaded by a 45 yd3 (34 m3) diesel-hydraulic and electric shovel and 22 yd3 (17 m3) wheel loader. Drill and blast will be undertaken with track mounted drill rigs drilling 10 ¾ inch (273 mm) holes.

The treatment technology proposed for the project is conventional flotation concentration. The processing plant will consist of crushing and grinding circuits, followed by a flotation process to recover and upgrade copper and silver from the feed material.

Crushed material with the approximate particle grind size P80 of 6 inch (152 mm), will be fed to the grinding circuit via SAG mill feed conveyor. Oversized material from the SAG mill trommel screen will be conveyed to the pebble crusher. The pebble crusher will discharge to the SAG mill.

The product from the SAG mill will be fed into the grinding cyclone feed pump-box, from where it will be pumped to the primary cyclopack. The cyclone underflow product will report via chute to the ball mill for further grinding. The cyclone overflow product, with the approximate particle grind size P80 of 150 microns, is the final ground product and will report to the rougher flotation conditioning tank.

Flotation will consist of one rougher and two stages of cleaner flotation, with the single tower/Vertimill being used for the fine grinding of the rougher concentrate.

The copper concentrate will be thickened using a hi-rate thickener and the underflow pumped to the agitated stock tank prior to filtration, and the thickener overflow will be collected in the process water tank.

The tailings will be disposed of by dry stacking of filtered tailings. The tailings will be thickened prior to moving onto the tailings filtration plant.