Degassing data suggests Mt. Etna began showing signs of pressure buildup months before 2018 eruption

by Bob Yirka , Phys.org

Credit: CC0 Public Domain

A team of researchers from the Istituto Nazionale di Geofisica e Vulcanologia, in Italy, has found evidence showing that magma pressure had begun building up deep in Mt. Etna's reservoir several months before the 2018 eruption. They also found evidence of degassing. In their paper, published in the journal Science Advances, the group describes their study of data from gas monitors situated on the famous volcano.

Back in 2018, Mt. Etna, one of the world's most active volcanoes, erupted in a dramatic fashion on Christmas Eve, spewing ash into the air and forcing closure of airspace. Two days later, a magnitude 4.9 earthquake shook the area around the volcano wreaking damage and injuring four people. In this new effort, the researchers suggest that degassing inside the volcano for approximately six months before the eruption could have been a warning of what was about to happen.

Over the years, scientists have placed a host of sensors on and around the volcano, each of which give some clues about the processes involved. Some of those sensors measure gasses that are emitted by the volcano. Prior research has shown that the ratios of gasses change over time as the volcano undergoes changes. In their work, the researchers looked at ratios of sulfur dioxide, carbon dioxide, hydrochloric acid and helium isotopes—gasses that have been associated with the buildup of magma in the volcano's reservoir. Prior research has also suggested that pressure buildup of magma can be a signal suggesting that the volcano is on a path toward eruption. The researchers found that ratios of helium isotopes at five sites near vents on the volcano began increasing, up to a year before the eruption. They also found that the volcano began emitting more carbon dioxide approximately six months before the eruption and that there were fluctuations in many other gasses as well. They suggest that together the changes in degassing ratios could be an indication of magma pressure buildup leading to an eruption. They conclude their paper by suggesting that the eruption in 2018 was inevitable, because the volcano was extremely over-pressurized in the weeks before it blew.

Scientists detect earthquake swarm at Hawaii volcano

More information: Intense overpressurization at basaltic open-conduit volcanoes as inferred by geochemical signals: The case of the Mt. Etna December 2018 eruption, Science Advances (2021). www.science.org/doi/10.1126/sciadv.abg6297

Journal information: Science Advances 

© 2021 Science X Network

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Unified theory explains how materials transform from solids to liquids

by Lois Yoksoulian, University of Illinois at Urbana-Champaign

The mucus layer on the underside of a snail foot is one example of a soft material that 

yields to stress up to a certain point, then flows. This behavior, simplified in a new study

 from researchers at the University of Illinois Urbana-Champaign, is what helps the snail

 move without unwieldy sliding, similar to that of many other natural and synthetic materials

, from mud to the additives that make toothpaste flow when squeezed.

 Credit: Rodrigo Quarteu

Years of meticulous experimentation have paid off for researchers aiming to unify the physics that defines materials that transition from solids to liquids. The researchers said a new theoretical model could help develop new synthetic materials and inform and predict civil engineering and environmental challenges such as mudslides, dam breaks and avalanches.

The study, led by University of Illinois Urbana-Champaign chemical and biomolecular engineering professor Simon Rogers, unveils a unified mathematical expression that defines how soft-yet-rigid materials transition from a solid into a liquid flow when they exceed their specific stress threshold. The findings are published in the journal Physical Review Letters.

"The behavior of yield-stress fluids has traditionally been defined by trying to combine the physics of two different types of materials: solids and liquids," said lead author Krutarth Kamani, a chemical and biomolecular engineering graduate student at Illinois. "But now, we have shown that these physical states—solid and liquid—can exist together in the same material, and we can explain it using one mathematical expression."

To develop this model, the team performed numerous studies that subjected a variety of different soft materials to stress while measuring the individual solidlike and liquidlike strain responses using a device called a rheometer.

"We were able to observe a material's behavior and see a continuous transition between the solid and liquid states," said Rogers, who is also an affiliate at the Beckman Institute for Advanced Science and Technology at the U. of I. "The traditional models all describe an abrupt change in behavior from solid to liquid, but we were able to resolve two distinct behaviors that reflect energy dissipation via solid and fluid mechanisms."

The study reports that this development gives researchers a simple model to work with, making it easier to make large-scale calculations like those needed to model and predict catastrophic events like mudslides and avalanches.

"The existing models are computationally expensive, and researchers need to struggle with the numbers to get the calculations to be as accurate as possible," Rogers said. "Our model is simple and more accurate, and we have shown that through many proof-of-concept experiments."

The researchers said complex yield-stress studies of fluids are a hot topic for those investigating geophysical flows, waste remediation and industrial processes like new materials development, 3D printing and the minimization of waste transport costs. "Our model defines a basic example of solid-to-liquid behavior, but I think it will serve as a jumping-off point for researchers to make significant progress in defining the more complex yield-stress fluid phenomena."

New approach to soft material flow may yield way to new materials, disaster prediction

More information: Krutarth Kamani et al, Unification of the Rheological Physics of Yield Stress Fluids, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.126.218002

Journal information: Physical Review Letters 

Provided by University of Illinois at Urbana-Champaign 

ROBO TRUCK
Vale launches self-driving trucks at its largest mine

Reuters | September 2, 2021 

(Image courtesy of Vale)

Brazilian miner Vale SA said on Thursday it had begun using self-driving trucks for the first time at its Carajas complex, its largest iron ore mining operation, as it continues to expand its use of the driverless technology.


Vale expects to boost productivity and safety by using the trucks to haul iron ore, said Pedro Bemfica, the executive heading the autonomous technology program.

The miner’s six self-driving vehicles at Carajas are nearly twice as tall and more than three times as wide as a conventional trucks and capable of holding 320 tonnes of iron ore.

The behemoths will operate alongside its fleet of about 120 normal offroad vehicles at Carajas, which is located in the northern Amazon state of Para. The company plans to add four additional self-driving trucks by year’s end.


THE COMPANY’S ENTIRE FLEET OF 13 OFFROAD VEHICLES IN THE BRUCUTU MINE IN SOUTHEASTERN MINAS GERAIS STATE IS AUTONOMOUS

The company forecasts that the trucks, which operate constantly and at a higher speed, will cut fuel consumption by about 5% and help Vale’s plans to cut its greenhouse gas emissions.

Costs related to wear-and-tear should also be lower with less spending needed on lubricant and tires.

“The principle objective is really to bring safety,” said Bemfica. “We launched this technology in trucks with the objective of removing people from inherent risk.”

The company’s entire fleet of 13 offroad vehicles in the Brucutu mine in southeastern Minas Gerais state is autonomous, and there has not been a single accident since the technology was first introduced there in 2016, he said.

The executive said the company intends to invest $64 million in expanding its fleet of self-driving trucks to 37 units at Carajas, although he did not give a clear timeframe for when that would be completed.

Vale also has four autonomous drilling rigs at Carajas and plans to add another three by the year’s end, Bemfica said.

(By Marta Nogueira and Jake Spring; Editing by David Evans)

Offshore drilling ban and mining curbs edge closer to passage

Bloomberg News | September 2, 2021 | 

Alaska Arctic National Wildlife Refuge. Aerial with mountains and Ivishak River. 

Stock Image.

Legislation to block oil drilling in most U.S. waters and Alaska’s Arctic National Wildlife Refuge edged closer to passage Thursday, as the House Natural Resources Committee rejected more than a dozen changes sought by Republicans.


The bill would slap new fees on oil and mining companies and effectively block the proposed Resolution Copper mine in Arizona while doling tens of billions of dollars to climate resilience, drought relief, conservation and other programs.

LEGISLATION WOULD ABOLISH A FOUR-YEAR-OLD REQUIREMENT THAT THE GOVERNMENT SELL DRILLING RIGHTS IN THE ARCTIC NATIONAL WILDLIFE REFUGE’S COASTAL PLAIN

The committee is expected to approve the bill next week after spending roughly nine hours considering the measure Thursday. Congressional Democrats then would fold the measure into the broader $3.5 trillion tax-and-spending legislation they are developing to expand the government’s role in health care, combat climate change and fulfill much of President Joe Biden’s economic agenda.

On Thursday, panel Democrats united in party-line votes to reject Republican-backed amendments to eliminate proposed fees and restrictions on oil operations, among other changes. More amendment votes are expected when the committee resumes considering the bill on Sept. 9.

The legislation would bar the sale of new oil and gas leases in Pacific and Atlantic waters as well as the eastern Gulf of Mexico. It also would abolish a four-year-old requirement that the government sell drilling rights in the Arctic National Wildlife Refuge’s coastal plain while voiding nine leases issued in that northeast Alaska region earlier this year.

Other provisions would rule out domestic uranium production near the Grand Canyon, create annual fees of up to $10,000 per mile on offshore pipelines and effectively block the Resolution Copper Co. mining project proposed by Rio Tinto Plc and BHP Group Plc in Arizona.

(By Jennifer A. Dlouhy)

Native Americans lose bid to halt digging at Nevada lithium mine site
Reuters | September 3, 2021 | 

(Photo courtesy of LAC)

A U.S. federal judge ruled on Friday that Lithium Americas Corp may conduct excavation work at its Thacker Pass lithium mine site in Nevada, denying a request from Native Americans who said the digging would desecrate an area they believe holds ancestral bones and artifacts.


The ruling from Chief Judge Miranda Du was the second victory in recent weeks for the project, which could become the largest U.S. source of lithium, used in electric vehicle batteries.

The court is still considering the broader question of whether former President Donald Trump’s administration erred when it approved the project in January. That ruling is expected by early 2022.

Du said the Native Americans did not prove the U.S. government failed to properly consult them during the permitting process. Du in July denied a similar request from environmentalists.

THE COURT IS STILL CONSIDERING THE BROADER QUESTION OF WHETHER FORMER PRESIDENT DONALD TRUMP’S ADMINISTRATION ERRED WHEN IT APPROVED THE PROJECT IN JANUARY

Du said, though, that she was not dismissing all the Native Americans’ arguments, but felt bound by existing laws to deny their request.

“This order does not resolve the merits of the tribes’ claims,” Du said in her 22-page ruling.

Vancouver-based Lithium Americas said it would protect and preserve tribal artifacts.

“We’ve always been committed to doing this the right way by respecting our neighbors, and we are pleased today’s ruling recognizes our efforts,” Lithium Americas Chief Executive Jon Evans told Reuters.

No digging can take place until the U.S. Bureau of Land Management issues an Archeological Resources Protection Act permit.

The Burns Paiute Tribe, one of the tribes that brought the lawsuit, noted that the bureau told the court last month that the land holds cultural value for Native Americans.

“If that’s the case, well then there’s going to be harm if you start digging into the landscape,” said Richard Eichstaedt, an attorney for the Burns Paiute.

Representatives for the bureau and two other tribes who sued were not immediately available to comment.

(By Ernest Scheyder; Editing by David Gregorio and Rosalba O’Brien)

Centerra says 40 metres of water at Kumtor pit a threat to workers, environment

Cecilia Jamasmie | August 31, 2021 | 

Centerra says this photo, taken in August, indicates there may be at least 40 meters (131 feet) of water at the bottom of the Kumtor central pit (Image courtesy of Kumtor Gold Company.)

Canada’s Centerra Gold (TSX: CG) said on Tuesday there are at least 40 meters of water at the bottom of its seized Kumtor gold mine in Kyrgyzstan and “abnormally” large amounts running down the pit walls, which it said could lead to catastrophic events.


The Toronto-based miner said that in the three months the former soviet nation has been running the mine, the pit has flooded with more water than they ever saw collect in the over 25 years of the operation under its control.

While the government-controlled Kumtor Gold Company (KGC) said the mine is stable and running at full speed, Centerra said it has photographic evidence suggesting the contrary. They include a video posted on August 15 on KGC’s Facebook page.

“Based on these images, Centerra believes at least 40 meters of water may be at the bottom of the Kumtor central pit (…) This has put the entire mine and its workers at risk of potentially catastrophic events, not to mention the real harm to the environment.,” the company said in an emailed statement.

The mine under Centerra’s operation (left) and current on right. (Courtesy of Centerra Gold.)

The miner believes urgent action is needed to address critical safety and operational issues.

“This is massive and the entire situation presents an imminent danger at many levels, not just the water in the pit, but also the tailings storage facility due to glacier melt”, Lindsay Newland Bowker, executive director of World Mine Tailings Failures told MINING.COM.

“The Kyrgyz government has zero capacity and no money to take on a proper assessment or correction of this problem,” she added.

The mine pit slices through two glaciers — Lysyi and Davidov. This vicinity and the practice of storing waste rock directly on the glaciers represents a risk to the enormous natural ice sheets, according to data compiled by Bankwacht Network.

In response to Centerra’s allegations, KGC the water levels in the pit were normal. To support this allegations, it included in its statement photos of similar amounts of water in the pit dating back to 2010, when Centerra operated the mine. “We believe that all the information presented in [theCenterra] press release is untrue and contains elements of destructive panic,” KGC said.

Water is a danger in pits in several ways, including affecting slope stability and a potential leak of the metal-rich water stored there, known as mine drainage, says Geoff Beale from Piteau Associates, a Canadian geotechnical and water management consultancy.

“WATER IS A DANGER IN PITS IN SEVERAL WAYS, INCLUDING SLOPE STABILITY AND A POTENTIAL LEAK OF THE METAL-RICH WATER STORE THERE, KNOWN AS MINE DRAINAGE

”GeofF Beale, Piteau Associates

In an online seminar last year, Beale — who is also co-editor of the CSIRO Guidelines for Evaluating Water in Pit Slope Stability — noted the amount of water contained in a pit can be an accident catalyzer.

“Water changes the resistive forces of a slope and creates driving forces. It’s a very simple concept. It’s two forces acting at the same time— the downward pressure of the rocks that holds the material together and the other is the upper pressure of the water that can break the rock. The less water, the more resistance,” he said.

Centerra chief operating officer Dan Desjardins, who managed the mine for five years as the president of Kumtor Gold until January 2020, urged the mine’s current management to hire independent experts to assess the condition of the mine and to publish the findings.

“Clean glacial water is flowing uncontrolled into the pit. This is dangerous and we are worried about the safety of workers,” he said. “When we operated the mine, nearly all of the glacial melt water was intercepted before it reached the pit.”

One of the most well-known landslide in an open pit is the one that happened at Rio Tinto’s Bingham Canyon copper mine in Utah in 2013. The incident did not claim victims, but it damaged equipment, a building structure, slowed output, and took at least three years to repair.

Resource nationalism

The Kyrgyz’s parliament passed in early May a law allowing the state to temporarily take over Kumtor gold mine, the country’s biggest industrial enterprise.

Kyrgyzstan’s move came after a court fined Centerra’s unit Kumtor Gold Company (KGC) more than $3 billion for allegedly dumping mining waste on glaciers near the mine 4,000 meters above sea level. A state commission also recently alleged that KGC owed more than $1 billion in unpaid taxes.

Kumtor is the largest of Centerra’s three gold mines, accounting for over 50% of the company’s total output. Since the seizure, Centerra’s Kyrgyz subsidiaries have filed for Chapter 11 bankruptcy protection. The company has also sued the new external manager of the mine, alleging that he conspired to steal the asset while he was a director.

Centerra said at the time that KGC and the Kumtor Operating Company CJSC (KOC) were solvent, with total assets (including the Kumtor mine) above $1.1 billion and no external bank debt.

Kumtor Gold Company’s video:





The Canadian miner is not a party to or affected by the Chapter 11 filing and remains with more than $883 million in cash and almost $1.3 billion in liquidity as of June 30, 2021, it said earlier this month.

The mine has produced more than 13.2 million ounces of gold between 1997 and the end of 2020. Last year’s output was slightly over 556,000 ounces. Centerra guided in January for Kumtor to produce 470,000 to 510,000 ounces of gold, with improving grades and production expected towards year-end.

The operation is considered by analysts a classic example of the risks tied to resource nationalism, as it has been for years the subject of both renegotiations protracted legal battles.

Centerra is currently seeking to hold the Kyrgyz government and Kyrgyzaltyn responsible for all losses and damages that result from their coordinated campaign to seize the gold mine in violation of longstanding investment agreements and without compensation to Centerra.

The company also seeks to prevent the Kyrgyz government and Kyrgyzaltyn from taking any further actions to nationalize the mine or improperly dispose of it.

Its two units, KGC and KOC, filed last week a motion in a US Bankruptcy Court seeking penalties of $1 million a day against the Kyrgyzstan government.

Eight people suffocate at Burkina Faso mine after police fire tear gas

Reuters | September 2, 2021 | 

Bissa mine in Burkina Faso. Image: Nordgold.

Eight people suffocated to death when police in Burkina Faso used tear gas against unauthorised gold miners at Nordgold’s Bissa mine, a prosecutor said on Thursday.


About 40 were on site on Wednesday when the police fired tear gas, which “caused panic and the suffocation of the clandestine gold miners”, national prosecutor Wendyam Lambert Sanfo said in a statement.

Sanfo said charges for involuntary homicide would be brought in the case but did not specify against whom. Four people were also arrested on charges of burning 10 vehicles on the site.

RELATED: IAMGOLD halts transport to and from Burkina Faso mine after attack

The police said in a statement on Monday that they had discovered the bodies of six miners at the mine but did not mention firing tear gas.

Nordgold, a Russia-focused miner majority owned by Russian billionaire Alexei Mordashov and his sons, did not immediately respond to a request for comment.

Burkina Faso and neighbouring West African countries have experienced a gold rush in recent years as informal miners, starved of other well-paying economic opportunities, dig for ore in often dangerous conditions.

(By Thiam Ndiaga and Aaron Ross; Editing by Grant McCool)

ECOCIDE

Congo says 12 dead, 4,400 sick following Angola mine tailings leak

Reuters | September 2, 2021 | 

Credit: Catoca Mining Company

The Democratic Republic of Congo will seek compensation from the owners of an Angolan diamond mine after a tailings dam leak polluted drinking water, causing 12 deaths and making thousands of people ill, the country’s environment minister said on Thursday.


The late-July leak from Angola’s biggest diamond mine turned a tributary of the Congo River red following a rupture in a spillway for the mine’s tailings dam, which stores mining industry waste meant to stay undisturbed.

Researchers at Kinshasha University last month pointed to “huge pollution” that affected some 2 million people, killed fish and caused diarrhoea among river communities.

Congo, which shares a 1,600-mile (2,575 km) long border with Angola, will seek compensation in line with the “polluter pays” principle, where those who produce pollution should bear the cost of mitigating it, Eve Bazaiba told a media conference after visiting the country’s southern Kasai province.

Bazaiba said she could not yet say how much in damages the country could seek. She said 4,400 people had fallen ill.

CATOCA SAID IT IMMEDIATELY SOUGHT TO REPAIR THE LEAK, BUILT TWO DYKES TO FILTER SEDIMENT OUT OF THE WATER AND BY AUG. 9 THE BREACH WAS SEALED

The mine’s operator, Sociedade Mineira de Catoca, did not immediately respond to a request for comment on the damages claim and deaths listed by the minister.

The leak and deaths represent the latest in a string of tailings disasters for the global mining industry that investors, executives and environmentalists have tried to curtail with safety and inspection standards introduced last year.

Not all companies – including Catoca – have publicly committed to the standards, which are non-binding, further fuelling questions about how the standards can cause industry-wide change if not all mines and mining companies adhere.

Catoca, a joint venture between Angolan state diamond company Endiama and Russia’s Alrosa, said in a press release last month that tailings leaked into the Lova River, a tributary of the Tshikapa River, which eventually feeds into the Congo River, in late July.

Satellite images reviewed by Reuters show the Tshikapa turned red on July 25.

Catoca said it immediately sought to repair the leak, built two dykes to filter sediment out of the water and by Aug. 9 the breach was sealed.

Alrosa, which holds a 41% stake in Catoca, did not disclose the incident and told Reuters it was not its responsibility to do so as it does not control the mine site.

Endiama, which also holds 41% of the company, also said it was Catoca’s responsibility to make the incident public. In answers to Reuters’ questions, Endiama said it was made aware of the leak on July 30, three days after Catoca said it was seen.

Catoca said it donated food baskets to riverine communities to mitigate the impact of the pollution. Endiama said other measures were being worked on, without providing details.

The International Council on Mining and Metals (ICMM), the global mining industry trade group, which worked to draw up standards on tailings dams, said it had offered support to Alrosa – which is not an ICMM member – after the leak.

Adam Matthews, chief responsible investment officer for the Church of England Pensions Board, which was also instrumental in drawing up the safety norms, said the leak was a reminder that tailings management requires continued attention from industry, governments and investors.

He said investors and the United Nations are developing an Independent International Institute which would implement the standard and verify companies’ compliance with it.

(By Hereward Holland, Helen Reid and Polina Devitt; Editing by Ernest Scheyder and Richard Pullin)

US court overturns Trump water rule on environmental grounds
MINING.COM Editor | September 3, 2021 | 3:55 am News USA Copper Gold

The San Pedro River is one of the Arizona’s waterways affected by the Trump-era clean water rules. (Image courtesy of Katja Schulz | Flicr Commons.)

Environmental groups welcomed a federal judge’s decision this week to overturn the Trump administration’s scaled back clean water rule limiting the number of waterways overseen by federal regulations.


The ruling by Arizona district court judge Rosemary Marquez said the 2020 Navigable Waters Protection Rule was filled with “errors” and has negatively impacted arid states in the west, particularly Arizona and New Mexico.

The draft version of the rule, which went into effect near the end of Trump’s time in office, was specifically criticized by the Environmental Protection Agency’s (EPA) own science advisory board. They said the norm ignored current scientific understanding and was incompatible with the aims of the Clean Water Act.

“WE WOULD LIKE TO AVOID HAVING EACH ADMINISTRATION CHANGE THE REGULATIONS WHICH LEAVE GREEN ENERGY, MINING, HOUSING AND CRITICAL INFRASTRUCTURE PROJECTS IN QUESTION” 

Steve Trussell, executive director of the Arizona Rock Products Association

Mining and farming representatives were not pleased with the ruling. Steve Trussell, executive director of the Arizona Rock Products Association, said the ruling reinstates uncertainty around what is regulated, what the regulations are, and how they will be implemented.

“Sadly, the uncertainty of this decision will only harm the … parties which represent job creators and the backbone of America’s economy,” he told Arizona PBS. “We would like to avoid having each administration change the regulations which leave green energy, mining, housing and critical infrastructure projects in question.”

For the six federally recognized Native America tribes who had sued the EPA and Army Corps for passing a rule they claim fail to protect their waterways, this week’s verdict is a victory.

“The court recognized that the serious legal and scientific errors of the Dirty Water Rule were causing irreparable damage to our nation’s waters and would continue to do so unless that Rule was vacated,” said Janette Brimmer, attorney for Earthjustice, which represented the tribes.

The tribes include the Pascua Yaqui Tribe, Tohono O’odham Nation, Quinault Indian Nation, Menominee Indian Tribe of Wisconsin, Fond du Lac Band of Lake Superior Chippewa, and the Bad River Band of Lake Superior Chippewa.

(With files from Reuters)

Barrick, NovaGold closer to Donlin mine decision
Cecilia Jamasmie | September 3, 2021 | 

Donlin Gold project, Alaska, being developed by Novagold, which recently joined EY’s Canadian Mining Index. (Image courtesy of Novagold Presentation, Nov. 2020.)

Joint venture partners Barrick Gold (TSX: ABX) (NYSE: GOLD) and NovaGold Resources (TSX: NG) have published the first results of their 24,000-meter drilling program for their Donlin gold project in Southwest Alaska, which will likely provide the final data needed for an optimized mine plan at the 39-million-ounce gold asset.

The Donlin Gold Project is an intrusion-related gold deposit in southwest Alaska, USA. It is currently in the late feasibility stage of development and is 50/50 owned by NovaGold (TSX:NG) and Barrick Gold (TSX:ABX). The Tintina Gold Province is bordered by two large fault systems and hosts many gold deposits of varying types.

Donlin Gold Project, Alaska | Geology for Investors

www.geologyforinvestors.com/donlin-gold-project/

The primary objective of the 2021 drill program is to complete the necessary work to validate and increase confidence in recent geologic modeling concepts at Dolin.

Having completed 18 drill holes, plus additional partial results for another 11 holes, the partners have detected significant new high-grade drill hole intercepts that hint of potential feeder zones for the larger system.

BARRICK AND NOVAGOLD ARE SIMULTANEOUSLY MAKING HEADWAY ON OBTAINING THE FINAL STATE PERMITS NEEDED TO DEVELOP AN OPERATION THAT MATCHES THE WORLD-CLASS DEPOSIT

“The 2021 drill program has been enormously rewarding — allowing us to improve our knowledge of the geology and mineralization in the ACMA and Lewis deposits which in turn will provide the information required to proceed with a new feasibility study,” Greg Lang, Novagold’s President and CEO, said in the statement.

After this year’s drilling season, Barrick and Novagold expect to be able to turn their attention towards a feasibility study for the proposed mine. The companies are simultaneously making headway on obtaining the final state permits needed to develop an operation.

The pending and final state authorization includes water permits and a right of way agreement for the 482km (300-mile) pipeline that will deliver natural gas to the Donlin mine.

The National Environmental Policy Act (NEPA), the US Army Corps Engineers and Bureau of Land Management have already granted Barrick and Novagold the federal permits needed to develop the mine in the second largest gold-producing state in the US.

According to the partners, the Donlin deposit hosts one of the largest and highest-grade undeveloped open-pit gold endowments in the world, with an estimated 39 million ounces of gold grading 2.24 grams per tonne in the measured and indicated resource categories.