Thacker Pass Lithium Mine – Draft Environmental Impact Statement reaction

A panoramic view of the proposed Thacker Pass lithium mine in northern Humboldt County, Nevada - photo: Lithium Nevada

In the summer of 2019, Lithium Nevada Corporation (LNC) submitted a detailed plan for the Thacker Pass lithium mine project in northern Humboldt County, Nevada to the US Bureau of Land Management (BLM) and Nevada Division of Environmental Protection (NDEP).

On February 5 of this year, the BLM published a Notice of Intent to Prepare a Draft Environmental Statement (DEIS) for the mine. Once the notice of intent was published, the agency has 12 months or fewer to process the EIS under a Trump Administration executive order that mandates a one year timeline.

On July 29, the Draft Environmental Impact Statement was published, which started a 45-day public comment period that ends on September 11.

Adding impetus to the approval of the mine is another Trump Administration executive order that gives the project strategic significance. Executive Order 13817 is dated December 20, 2017 and gives the Department of the Interior, in consort with the Department of Defense and other related agencies, the directive to create a list of critical minerals. Lithium is on the list.

To meet the NEPA decision deadline, a Record of Decision must be issued by February 5 of next year. Lithium Nevada said it is prepared to begin a 2 year construction phase soon after.

The Thacker Pass Lithium Mine

Recently, Tim Crowley, vice president of government and community relations for Lithium Nevada, gave a presentation on the Thacker Pass project to the Legislative Committee on Energy. Crowley said the mine will be able to meet all US lithium demand and enable the US to become a net exporter of the mineral largely used in rechargeable batteries.

“We have a very special deposit. It’s one of the biggest on the planet,” Cowley told lawmakers during the online meeting. “The mine life is long. We can say with certainty it’s at least 40 years long and we can say with some high probability that it will go far beyond that.”

The Silver Peak lithium mine in Nevada is currently the nation’s only active lithium mine. This operation has been producing lithium from Clayton Valley water, 20 miles southwest of Tonapah, since the mid-1960s.  The Albemarle Corporation based in Charlotte, North Carolina now operates the mine.

Like lithium mines in Argentina and Chile, the Silver Peak mine extracts lithium from salt flat brine. The Thacker Pass project is different in that the lithium is entrained in clay-like material associated with an ancient super-volcano. An open pit is proposed with the remediation objective of back filling the hole.

Lithium Nevada has spent the last couple years refining a processing method in their Reno laboratory that will separate the lithium from the clay using sulfuric acid.

The Thacker Pass Project is unlike most mining projects in that it is proposed to be a carbon-neutral mine operation. In order to fulfill the objectives of processing ore using sulfuric acid and generating electric power, a sulfuric acid plant will be built on-site so that lithium can be leached, or dissolved, from the extracted ore during mining operations and the heat generated through the creation of sulfuric acid will be used to generate electricity.

“The Thacker Pass mine will be the first processing facility that uses sulfuric acid to extract lithium from sedimentary clay; however, sulfuric acid has been used to extract lithium from hard rock deposits for decades,” Alexi Zawadzki, CEO of Lithium Nevada wrote in email correspondence with the Ally. “Once the lithium is dissolved, it can be concentrated and purified to produce high-quality lithium compounds for batteries. Any excess acidity is neutralized to produce calcium sulfate (gypsum, also known as the main material in wall-board) and magnesium sulfate (Epsom salt).”

An aerial view of the proposed Thacker Pass mine site – photo: Lithium Nevada

Excess heat generated from the burning of sulfuric acid at the plant will be used to power the project, with surplus electricity being sold back to the power grid. The practice of using sulfuric acid in mining operations is not wholly unusual, especially when mining phosphates.

“We took a fresh look at the potential processing methods and decided we could significantly lower our water use, increase our lithium recovery and generate power at the same time by utilizing a sulfuric acid leaching process modelled on how phosphates are mined and processed around the world,” Zawadzki said. “We are proud to be incorporating this into our design plans on a large scale, which we expect will significantly reduce our overall carbon footprint.”

The mine will have a connection to the electrical grid along with a diesel generator, but day-to-day, Lithium Nevada anticipates that having the sulfuric acid plant on-site will play a major role in reducing the proposed mine’s carbon footprint.

“Producing sulfuric acid on-site will reduce the materials transported to the mine by over 50 percent, thereby reducing truck traffic and offsite [greenhouse gas] emissions associated with the project,” Zawadzki said. “Additionally, steam produced from the sulfuric acid plant will be used in the lithium process for evaporation of water during the crystallization of salts, instead of burning natural gas to create necessary steam for the process.”

Reaction to the Draft Environmental Impact Statement

Edward Bartell, a rancher who owns property both above and below the proposed Thacker Pass mine, expressed concerns about the proposed mining operations in a phone interview with the Ally. Ultimately, if the proposal for the Thacker Pass mine is approved, Bartell envisions a significant change to his lifestyle and property.

“We run cattle out in the area and we have our property above the mine site that has several springs on it that flow year-round that not only adds aesthetic value to the property, but is also important for stock water because we’re concerned about those springs drying up,” Bartell said.

“Then the property we own below the mine site, which is in range of their production well, we’re concerned that dropping the water table will transform that ground into a desert that will devalue the property as well as reduce the amount of forage that it produces. These are very remote areas, so if you don’t have stock water out there, you can’t economically haul water up the mountain on a very poor road. So it would be very difficult to run stock if they started drying up our springs.”

Lithium Nevada will operate an open pit but does not, according to the DEIS, plan to lower the local groundwater table to access the ore until 20 years into the 40 year project.

In order to convert sulfur to sulfuric acid, approximately 100 acre-feet of water will be used per-year. According to Zawadzki, however, the Thacker Pass project will recycle nearly all water with the exception of water used for dust mitigation, moisture in the tailings (which will be pressed to remove water), and water used for evaporative cooling. The project also plans to use rainwater acquired on the mine property and tailings pile area for its operations.

“Most of the 2,600 acre-feet of water to be used in the first phase of our operations comes from existing water rights we have acquired in the Quinn River Basin,” Zawadzki said. “In most cases, we are converting agriculture water rights to mining rights, which requires us to forfeit 23 percent of the right. Therefore, our Project will decrease pumping and consumption in the basin and is not expected to have an effect on any existing water rights in the Quinn Valley.”

The area where Lithium Nevada proposes to develop the Thacker Pass Lithium mine – photo: Lithium Nevada

Bartell, however, is not convinced that the water table will not be affected by the project.

“When they test-pumped their proposed well, it showed after two and a half days that there was a draw down on our stock water well, so there’s a direct hydrologic connection,” Bartell said. “So it’s clearly going to draw down wells, but there’s going to be a significant drop in the water table that vegetation can access right now because we have a really high water table out there. So it’s going to significantly devalue our property.”

John Hadder is executive director of Great Basin Resource Watch (GBRW). He proposes an alternative option for the mine’s water access.

“What they could do is they could draw the water from the original point of diversion which is at the ranch that was purchased on the eastern side of Quinn Valley, and they could then pipe the water over to the mine site,” Hadder said. “It would cost them more to do that and the energy usage would be a little higher, but in terms of the point of diversion and affecting other water rights, that would probably be better for other people that are using water in the basin because the point of diversion is right there at the ranch they purchased.”

Geochemistry

Zawadzki said the waste stream of materials remaining after the desired product, in this case lithium, will be extracted and cloistered on a “zero-discharge” facility.

“Geochemistry analysis of the tailing material indicates that the clay tailings do not contain appreciable sulfide sulfur and are unlikely to generate acid from the oxidation of sulfides,” Zawadzki said. “To mitigate against potential impacts, the tailings facility will be constructed as a zero-discharge facility. Tailings material will be filtered, stacked and then stored on lined containment and covered with waste rock/growth media at closure; therefore, no degradation to groundwater is expected to occur.”

Bartell has reservations that some of that backfill will contain radioactive elements like Uranium. Chevron looked for Uranium on the proposed mining site in the 1970s.

“If you put sulfuric acid on ore, it will leach multiple things out, including the Uranium that Chevron’s mining claims were originally seeking,” Bartell said. “According to the EIS, when they did sampling, roughly 50 percent of the samples contained elevated levels of Uranium. So there’s both the concern of leaching the Uranium and if they dump the rocks that contain a lot of Uranium and other toxic elements into the pit for backfill, there’s a concern that that will have direct contact with the groundwater.”

Unlike gold mines where a cyanide solution is sprayed onto mountains of ore to separate the gold from rock, the leaching of lithium from soft clay using sulfuric acid will occur inside a building and in a closed container. And though the tailings will be pressed to remove excess water before being used to backfill the pit, Bartell is concerned that if radioactive elements somehow infiltrate the groundwater, that could pose risks to the local population.

“We are enormously concerned if groundwater becomes contaminated for people that live nearby and have house wells, but also we have stock water wells out there,” Bartell said. “We don’t want to have our stock water wells containing radioactive elements from the backfill that leeches into the groundwater, especially if you’re putting [that contaminated groundwater] on crops.”

Groundwater Quality Concerns

Great Basin Resource Watch expressed concern about pressure to approve the mine in fewer than 12 months.

“Lithium Americas, proponents of the proposed Thacker Pass Lithium mine north of Winnemucca, south of Montana Mountains, is moving ahead with federal permitting,” wrote GBRW in a recent newsletter. “GBRW witnessed significant community concerns raised about this mine project at a public BLM-facilitated scoping meeting, earlier this year. The focus on lithium for batteries is putting pressure on state and federal agencies to move this and similar projects through analysis quickly. GBWN will hold the line on the need for transparency and for a thorough evaluation of this and any other major mine project.”

John Hadder of GBRW shares Bartell’s concerns about the potential risks the backfilled pit might have on the local environment.

“Their current proposal is to backfill the open pit, which is fine, but there’s going to be a potential contamination plume that could result from that,” Hadder said. “So they’ve got mitigation measures in the EIS and we’re going to recommend that they arrest the problem before it gets into the groundwater.”

Regarding uranium, Zawadzki, asserts that only low concentrations were found in the deeper volcanic rock that is lower than the ore holding the lithium concentrates they will be extracting.

“[Chevron] found low concentrations [of Uranium] in the deeper volcanic rock, at lower depths than the Thacker Pass ore,” Zawadzki said. “But they discontinued exploration when concentrations did not prove high enough to support commercial extraction. The lithium ore is in clay sediments that sit above the volcanic rock.”

In the event that a radioactive element such as uranium is extracted and appears in the tailings pile, Zawadzki said those radioactive elements will be contained.

“LNC has taken a very cautious approach to Uranium management, and tailings management in general, that prioritizes public and wildlife safety,” Zawadzki said. “Tailings will be filter pressed and dry stacked on a synthetically lined, zero-discharge facility.”

Nevada Lawmakers Voice Support

During the recent Legislative Energy Committee meeting, several lawmakers expressed the need for a US-based source of lithium and lithium chemicals, especially when that source is in Nevada.

State Senator Patricia Spearman said during the virtual meeting that she is in full support of the project.

“One of the things that I think as we move forward with any type of legislation, the criticality of moving that operation from China, more than operation here, because we’re about to get ourselves in the same situation from a national security measure as we are with fossil fuels, because we will be dependent upon someone else for the batteries for everything else that we need for a combat readiness state.”

Nevada state Senator Chris Brooks, a noted advocate for the development of renewable energy, spoke in support of the project.

“This is an exciting project and it is I would say, it is critical to the national defense of our nation. And it’s definitely critical to the future of the Nevada economy and decarbonisation and the role that we could play in decarbonisation across the planet right here in Nevada.”

Economic Development

Northern Humboldt County is sparsely populated. Economic development is a challenge. The region is home to Nevada’s largest irrigated farm and a few major gold mines, but outside the county seat of Winnemucca, average annual incomes plummet. For instance, a high percentage of residents in McDermitt and Fort McDermitt Paiute and Shoshone Indian Reservation live in severe poverty.

What the new mining operation will spell for the rural Humboldt County is difficult to predict. A 2017 study by Buddy Borden, a specialist in community and economic development for the University of Nevada Reno Cooperative Extension and Tom Harris, professor and director of the University Center for Economic Development, University of Nevada, Reno, examined the potential economic impact of the Lithium Nevada Thacker Pass mine on Humboldt County.

The report has economic impact calculations for mine construction, mining operation, and processing. The impact model for mine construction concludes that for each $1,000,000 of direct investment in lithium mine construction generates an additional $214,545 in secondary impacts. Of the $1,214,545 of total impact, $452,978 is from personal income and supported 8.6 jobs per $1 million of mine construction spending. The study concludes that every $1,000,000 of direct investment generates $37,610 in state and local taxes and $96,079 in federal taxes.

The red dot in the interactive map below marks the location of the proposed Thacker Pass lithium mine.

With an eye toward beginning construction in 2021, Lithium Nevada has been working with Humboldt County rural communities to lay the ground work to develop a local workforce. Tildon Smart, chairman of the Fort McDermitt Paiute and Shoshone Indian tribe is on record in support of the project. Lithium Nevada recently purchased a van for the tribe, according to Tim Crowley, and is working on the reservation to recruit and train future mine employees.

Strategic Minerals and Corporate Ownership

During the recent meeting of the Legislative Committee on Energy, Tim Crowley described that Lithium Nevada as a chemical manufacturer going into the mining business. Lithium Nevada is subcontracting the mining component to North American Coal, which specializes in mining sedimentary deposits. North American Coal will rebrand as Sawtooth Mining in Nevada, according to Crowley.

Crowley said the Thacker Pass project is intended to help develop new manufacturing capabilities in the United States.

“That mineral (lithium) comes by and large from Australia and Chile. Forty-six percent of the mineral comes from Australia and 28 percent comes from Chile and Argentina. And then that concentrate, in most cases, is sent to China and it’s turned into the chemicals that we rely on and that are being utilized at the Tesla Gigafactory, the Panasonic Gigafactory, west of Fernley.

“So it’s China that really owns the chemical piece. And it’s South America and Australia that owns in a big way, the mineral piece, and we’re trying to fix that,” Crowley continued. “It’s a very convoluted supply chain. Even though we’re all striving to be clean and contribute to a clean electrified economy, we have this supply chain that makes no sense and we’re sending our materials all the way around the world and back before they actually get put into clean, reliable sources. Thacker Pass has the opportunity, the ability to provide that reliable source here in Nevada and in the United States that we need.”

“By bringing more lithium production, both the concentrate and the chemicals, online in the United States and in Nevada, we can promote more of the actual battery assembly factories to happen in the US as well.”

Ganfeng Lithium, a lithium compound manufacturer based in China, owns 15 percent of Lithium Americas stock. The Ally asked Alexi Zawadzki if Gangfeng has ownership rights on Thacker Pass lithium or derivative chemicals.

“Ganfeng has no ownership in Lithium Nevada or rights to the material from Thacker Pass,” Zawadzki said. “The Thacker Pass project is being designed to process battery-grade (e.g. exceptionally high purity) lithium products for use in battery materials. Therefore, our target customers will be companies that make cathodes and electrolyte for lithium ion batteries. Our strategy for Thacker Pass has always been to develop and improve the lithium-ion battery supply chain in the USA.”

“LNC is evaluating financing options to build the Thacker Pass mine including a partner in the Thacker Pass project. Current regulations restrict certain countries, including China, from owning strategic minerals deposits in the USA and the Company will fully abide by these laws.”

After the 45-day comment period closes on September 11, to comply with the new one-year deadline for NEPA decisions, a Record of Decision is due out no later than February 5 of 2021.