Coeur Mining’s growth mission on the Rochester silver and gold mine in Pershing County will add years of mine life to Rochester, the place mining started in 1986.
“We’re simply actually excited that this mission is making it doable to increase operations for one more 13 years,” stated Tim Dimock, Rochester’s assistant basic supervisor. “With out the growth, mine life will likely be restricted.”
And that 13 years might be prolonged with exploration that continues on the Rochester pit and at close by exploration tasks, he stated.
Dimock stated Rochester is a “very busy place” as work proceeds on the growth mission known as POA 11, which stands for Plan of Operations 11, with greater than 500 contractors on website, along with the 330 workers mining and processing ore whereas development is ongoing.
Coeur expects to fee the brand new mission in 2023.
“They’ve been engaged on the brand new facility since 2020, and the work picked up final yr and is heavy this yr,” he stated, reporting that rising commodity costs, provide chain issues and longer supply instances have had an influence on the mission.
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Coeur’s president and chief govt officer, Mitchell J. Krebs, said within the first-quarter earnings report that the corporate “is happy to report that the tempo of improvement exercise at our Rochester POA 11 growth mission continues to speed up, and almost 80% of the development price range has been dedicated.”
The 80% is $477 million of the estimated $597 million price of the growth mission.
The growth will embrace a brand new facility that features a new major crusher, two secondary crushers and two high-pressure grinding rolls that can make it doable to double manufacturing of gold and silver. Rochester produced 3.2 million ounces of silver and 27,051 ounces of gold in 2021.
Rochester produced 655,000 ounces of silver and 6,066 ounces of gold within the first quarter of this yr, in response to Coeur’s earnings report, down from 744,000 silver ounces and 6,904 gold ounces within the first quarter of 2021.
The corporate said that the decrease manufacturing was largely as a result of decrease placement charges on the leach pad within the prior quarter.
Coeur estimates that Rochester will produce between 3 million and 4 million ounces of silver and 35,000 to 43,000 ounces of gold in 2022.
Dimock stated Rochester now crushes 36,000 tons of ore to leach pads however plans to crush and place 87,000 tons on leach pads when the growth is accomplished.
The brand new facility additionally will embrace a brand new leach pad and a brand new Merrill Crowe processing plant on the growth website in Limerick Canyon that’s “on the opposite aspect of the ridge, due north of the Rochester pit,” Dimock stated, reporting that the leach pad now has been lined and has the over-liner of coarse materials.
“We are going to begin loading late this yr or early in 2023,” he stated.
SNC Lavalin is the engineering, procurement and development supervisor for the POA 11 growth mission, and TIC-The Building Firm is offering the structural, mechanical, piping and electrical instrumentation work.
Placement of ore on the brand new pad will start earlier than the brand new crusher and grinding facility are commissioned, with the ore coming from the Rochester Pit that has been mined for greater than 30 years.
Dimock stated that at present Rochester handles roughly 100,000 tons a day, with 64,000 coming from the mine and 36,000 rehandled from the crusher load-out to the leach pad.
“Rochester has a really low strip ratio proper now as almost 90% of the fabric being mined is ore,” he stated, including that along with mining 36,000 tons a day that’s immediately going to the crusher, Rochester mines 12,000 tons per day that goes on to the heap leach pad as run-of-mine ore and 9,000 tons a day goes to stockpiles for “later processing on the new Limerick Canyon Crusher, and solely 7ktpd of fabric is at present shipped to the waste rock storage facility.”
When the brand new facility is in use, all ore will likely be crushed, and there will likely be no run-of-mine leaching, Dimock stated.
In the meantime, Rochester crews are mining within the pit and utilizing the present crusher facility. The ore is processed on the older Merrill Crowe plant, which Dimock stated will keep in operation to course of ore from the in-use leach pads after the brand new facility is prepared. Rochester pours giant dore’ bars which might be primarily silver.
Coeur additionally reported in its first-quarter earnings report that the corporate plans to put in pre-screens on the prevailing crusher hall aimed toward mitigating the influence of nice ore materials and enhancing recoveries. The set up, nevertheless, might influence Rochester’s means to crush materials for as much as 30 days in the course of the present quarter.
The corporate stated that the expertise and information gained from using the pre-screens is predicted to be utilized to new screening know-how being built-in into the brand new crusher system flowsheet for the growth mission.
Rochester does concurrent reclamation on the leach pads, and one pad has been absolutely reclaimed and closed on the 17,044-acre mine website.
The present mining fleet contains 11 Komatsu haul vans which might be 150-ton, and Coeur has simply began buying 200-ton Caterpillar haul vans for the growth. Dimock stated there are 4 on website and three extra coming but this yr.
“We have now to order now to make sure they’re right here for the center of subsequent yr,” he stated. “We ordered a fleet of sunshine automobiles, and so they nonetheless haven’t arrived, so we needed to go to the used market.”
Rochester additionally bought a big Caterpillar front-end loader and has two hydraulic shovels, a Hitachi and a Komatsu.
Dimock stated the mine is coping with larger commodity costs, particularly for diesel, cyanide and energy, however larger gold and silver costs are serving to offset the upper prices.
Together with continued mining on the Rochester open pit, there are plans to mine once more on the adjoining Nevada Packard deposit, and Coeur is taking a look at mining potential on the Lincoln Hill exploration mission. That mining might begin in 5 – 6 years, Dimock stated.
Coeur acquired the Lincoln Hill, Gold Ridge and Wilco exploration tasks in November 2018. The U.S. Bureau of Land Administration’s Winnemucca workplace issued a document of choice in March approving superior exploration at Lincoln Hill for baseline knowledge assortment to evaluate mineral improvement inside an 8,457-acre boundary.
The growth elevated site visitors on the street resulting in Rochester, however Dimock stated Rochester workers journey by My Trip to Work buses from Lovelock and Winnemucca to the mine website.
The Rochester Mine is also concerned in a talented trades program, launched in 2021.
In Coeur’s environmental, social and governance practices and accountable mining operations report for 2021 launched in late April of this yr, a bit states that the aim of this system is to create a pipeline of scholars in diesel, electrical and millwrights to achieve expertise within the subject who hopefully get employed by Coeur full-time as soon as they graduate.
“5 college students enrolled in a commerce or vocational college joined our Rochester group to achieve real-life, on-the-job coaching. The scholars have been mentored by skilled leaders within the electrical, cell and glued upkeep areas of the mine,” the report says.
“The internships offered hands-on coaching within the areas of curiosity of every pupil whereas supporting the wants of the enterprise. College students have been additionally given the choice to proceed their internship from the summer-long program to weekend shifts all through the varsity yr,” the report states.
The report additionally says that “this system has confirmed so profitable it will likely be launched at our Kensington mine in Alaska this summer time as nicely.”
On the subject of Covid-19, Dimock stated Rochester “did an excellent job of managing it,” and Coeur obtained recognition for its efforts in the course of the pandemic, together with at Rochester.
The Nationwide Institute for Occupational Security and Well being, a division of the Facilities for Illness Management and Prevention, acknowledged Coeur for its cross-functional, technology-based Covid-19 response plan by granting the corporate the 2021 Mine Security and Well being Expertise Improvements Award. ￼