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Sep 16, 2020

   

Industry News

Nevada Copper back in production

5  Lecture minimum

ADELLA HARDING Mining Quarterly CorrespondentSep 3, 2020

Nevada Copper Corp. is on track toward full copper production from the Pumpkin Hollow Mine at Yerington after a COVID-19 hiatus for company employees while the contractor Redpath continued underground development.

Work was also done on the mill in those months to “make it more efficient,” said Tim Dyhr, vice president for external and government relations for Nevada Copper. The new mill was completed at the end of 2019 and had started operating in January and February before the company halted processing.

By early August, the company was calling back workers to begin ramping up for production that Dyhr said could take six months to reach “steady state.”

“There is a lot of work to get 5,000 tons of material a day. All those moving parts have to be synchronized,” he said in a phone interview.

Employment figures for Aug. 7 included 84 Nevada Copper employees, 115 Redpath consultants and 37 other contractors and consultants for a total of 236 workers. Roughly 40 percent are from Lyon County, including Yerington, Dyhr said.

Before the coronavirus and shutdown, Nevada Copper had about 100 employees, with some of those being laid off and some furloughed until the recall. The shutdown began in early April.

Arrangements call for copper concentrate to be hauled roughly 65 miles by truck from Yerington to the Tahoe Reno Industrial Center east of Reno to Nevada Copper’s truck-to-rail transload facility. The spur leads to the Union Pacific main line, and the concentrate will then head by rail to the West Coast for bulk shipment, according to Nevada Copper.

The headframe for Nevada Copper Pumpkin Hollow underground mine.

“There will eight to 10 trucks a day loaded with concentrate,” Dyhr said.

Redpath kept up its work on the underground mine while the mill was on care and maintenance, but Dyhr said coronavirus restrictions impacted the contractor, too. Only eight people at one time could be in the man cage that raises and lowers workers, usually 20 at a time, and they had to be masked.

Nevada Copper reported that the final East Main production shaft configuration and commissioning of the hoisting system in the production configuration was ahead of schedule and expected to be completed in the fourth quarter.

Meanwhile, copper is brought to the surface through the ventilation shaft, Dyhr said. The company had more than 150,000 tons of ore stockpiled for processing at the mill by early August.

The company announced in August that multiple key milestones were completed ahead of schedule on the final configuration of the East Main shaft, including that the shaft has been sunk and lined to final depth, permanent production hoist systems were installed and the headframe configured for production.

Tim Dake, General Manager for surface construction for Nevada Copper.

Nevada Copper also stated that equipping the shaft below the surface was progressing ahead of schedule, and the surface materials handling infrastructure has been completed and moved to the southside of the headframe.

As the shaft work continued, lateral development underground rates were ahead of revised plan targets, focusing on completing key underground infrastructure areas, improving access to ore, according to the company.

“We look forward to completing ramp-up of production at Pumpkin Hollow and continuing to advance our organic growth pipeline, including the open pit and exploration properties,” Nevada Copper Chief Executive Officer Evan Spencer said in an Aug. 6 news release.

The company developed the underground mine first and is advancing optimizations for a planned surface mine on the site through further exploration and infill drilling. The last program identified significant additional mineralization and indicated the ore body extends beyond the original pit boundary, Nevada Copper reported.

Dyhr said the focus now is on the underground operations and development of the surface mine depends upon financing and cash flow, as well as the new studies, but Nevada Copper already has permitting for the open pit mine.

Pumpkin Hollow is on private land following a land deal with the federal government. A 2015 bill in Congress allowed the U.S. Bureau of Land Management to sell more than 10,000 acres to the City of Yerington, which in turn conveyed all but 900 acres to Nevada Copper.

The federal land was valued at $1.8 million, and Nevada Copper paid for the arrangement that was finalized in 2016. Combined with land Nevada Copper already controlled, the land package grew to a little more than 10,860 acres.

Tailings from copper production are dry stacked, a process designed to save water in Mason Valley, where all the water rights are allocated, Dyhr said. Currently, the tailings go on a liner, but he said Nevada Copper hopes to demonstrate to the state that liners are not needed.

Dyhr said he is “very proud” of the dry-stack system that is more expensive but more environmentally friendly and conserves water. Traditionally, tailings require 8,000 acre-feet of water, but the dry-stacking method takes less than 4,000 acre-feet, for example.

Tailings are the solid waste material left behind after copper processing.

Nevada Copper also reported that it recently staked an additional land package totaling 680 acres contiguous to the current Pumpkin Hollow property for exploration potential.

The company has been down a long road toward full production at a project cost of $667 million. Bumps in the road in addition to COVID-19 included low copper prices that stalled shaft sinking in 2012 and efforts to obtain financing for Pumpkin Hollow.

Copper went below $2 per pound in 2012. Dyhr said the price was about $2.50 a pound in February and March of this year and rose to roughly $3 a pound this summer.

“I’ve been here 14 years, and the only reason I stay is that I like the project, and I like the town, and I want to see it happen,” Dyhr said.

The company was founded in 2005.

Nevada Copper reported in August that it had succeeded with certain capital agreements and entered into a streaming agreement with an affiliate of Triple Flag Precious Metals Corp. The streaming is for gold and silver production.

“We are very pleased with the strong demand from investors to participate in the company’s equity offering completed in July 2020 and would like to thank our existing shareholders and new institutional and retail investors for their support,” Evans said.

Pumpkin Hollow currently has a mine life of 14 years, but the open pit operation would add 20 years, Dyhr said.

He said Nevada Copper works closely with the community of Yerington and established the Pumpkin Hollow Community Advisory Council. The mine is roughly eight miles southeast of Pumpkin Hollow but is annexed into the city.

The advisory council toured Pumpkin Hollow in early August to view the mine and mill progress, Dyhr said.

“The site visit included the hoist house, headframe sub-collar, crusher, SAG (semi-autogenous grinding) mill, ball bill, flotation area, concentrate and tailings filter plant and the dry stack tailings, he said in an email after the tour.

Kellen Osborne of Redpath, the mining contractor for the underground development and shaft work, gave a presentation to the council, along with Nevada Copper managers Ryan Irvin, Tim Dake, Ian Larkins and Michael Bozarth.

The advisory council includes representatives of Lyon County, the City of Yerington, the Yerington Chamber of Commerce, the Northern Nevada Development Authority, Yerington Inn, Wild West Chevrolet, Snyder Land & Livestock, the Boys and Girls Club of Mason Valley, Yerington Theater for the Arts and the Yerington Paiute Tribe.