Engineering & Mining Journal

DEC 2018

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Page 15 of 115

REGIONAL NEWS - U.S. & CANADA 14 E&MJ • DECEMBER 2018 pany that owns interests in coal, ag- gregates and industrial minerals across the United States. A large percentage of NRP's revenues are generated from royal- ties and other passive income. In addition, NRP owns an equity investment in Ciner, Wyoming, a trona/soda ash operation and owns a construction aggregates company. Para Signs Clark to Work Gold Road Para Resources has entered into a services agreement with Clark Construction Group LLC, which will provide contract mining services at the Gold Road mine in Oatman, Arizona. The contract is initially on a "time and materials" basis, but will evolve into a unit pricing contract, which is being nego- tiated. The services agreement is an inter- im step to ensure work at the mine starts immediately. Clark has already mobilized project management to the site, and initial equipment and operational crews were ex- pected to arrive by the end of November. Work presently being conducted at Gold Road includes upgrading the venti- lation system to handle higher levels of production, upgrading of the main decline and haulage route to manage larger sized trucks, rehabilitation of secondary escape ways, and remediation of recently encoun- tered ground control issues. Maintenance, testing, repair and general cleanup of the mill is being conducted. The mill is ex- pected to be in functional condition by the end of 2018. Mineralized rock production is expected to commence in January with recommissioning of the plant with first gold pour anticipated in February. The start of production at Gold Road has been delayed by 45-60 days due to unforeseen ground conditions resulting from the dewatering of the lower levels of the mine, the company said. Management determined that the conditions were unsafe and need to be improved before mining can begin in the lower levels of the mine. Para is a junior producing gold mining company and owns 88% of the Gold Road mine and approximately 80% of the El Li- mon project in Colombia. Fluor Selected for Lithium, Boron Project in Nevada ioneer Ltd. is considering a lithium and boron mine outside of Tonopah, Nevada, and it has selected Fluor to provide a de- finitive feasibility study, and subsequent- ly, engineering, procurement and con- struction management (EPCM) services as the project progresses. "With the growing demand for electric vehicles and energy storage, Fluor is ex- cited to work with ioneer on our first lith- ium mine project in Nevada," said Tony Morgan, president of Fluor's Mining and Metals business. "Our team brings the right combination of technical and exe- cution expertise. We will leverage our full suite of integrated solutions tools, includ- ing our Zero Base Execution process and fit-for-purpose modular design strategy, to develop an execution approach to deliver this project safely and with excellence." The mine will extract and process ore to produce 20,200 tons of lithium carbonate and 173,000 tons of boric acid, annually. The full notice to proceed on the EPCM phase is expected in 2019 with first production expected in 2021. Updated PEA Supports Valentine Lake Development An updated preliminary economic assess- ment (PEA) has provided solid support for development of Marathon Gold's Val- entine Lake Gold Camp open-pit project in west-central Newfoundland. The prop- erty hosts four identified deposits: Mara- thon, Leprechaun, Victory and Sprite. The Sprite deposit is not included in current mine planning, pending additional explo- ration drilling to increase the resource. Gold recovery at Valentine Lake will be through separate milling and heap-leach- ing circuits. Standard surface-mining techniques will be utilized to develop the Marathon, Leprechaun, and Victory open- pit mining areas. The updated PEA estimates that Val- entine Lake will produce approximately 2.72 million ounces (oz) of gold over a 12-year operating life. Preproduction capital is estimated at $355 million. Life- of-mine average all-in sustaining costs of production are estimated at $666/oz. A prefeasibility study is in progress and is scheduled for completion in 2019. The Valentine Lake PEA calls for the milling facility to process 3 million metric tons per year (mt/y) of high-grade miner- alized material through crushing, milling, gravity recovery, flotation of gravity tails, flotation concentrate regrind, cyanidation leaching of the flotation concentrate, and flotation tailings via a carbon-in-leach (CIL) circuit, carbon elution, and a gold recovery circuit. CIL tails will be treated for cyanide destruction and routed to a tailings storage facility. The heap-leaching facility will process 3 million mt/y of low-grade mineralized mate- rial from open-pit operations through crush- ing, heap leaching, and carbon-in-column gold adsorption. The loaded carbon will be sent to the mill facility for gold recovery. "This updated study has benefited from 20,000 m of additional drilling since Febru- ary 2018, 9,000 metallic screen assays on historical drill core since the previous PEA resource, and an internal review of the proj- ect," Marathon President and CEO Phillip Walford said. "For example, initial and sus- taining capital costs have been cut by leas- ing the mining fleet instead of purchasing it. "The Marathon deposit has the poten- tial to develop an underground mine, but for now it is more cost effective to find open-pit resources at $10/oz rather than to drill for costlier underground resources." The Valentine Lake PEA was prepared by a team of independent consultants, including Lycopodium Minerals Canada Ltd., John T. Boyd Co., Apex Geoscience Ltd., and Stantec Consulting Ltd. Marathon deposit 3D block model looking northwest at Valentine Lake gold camp.

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