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Perpetua Resources Begins Investment in Water Quality Improvements at Historic Mine Site

Corporate Updates

405 S 8th Street #201, Boise, ID 83702

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NEWS RELEASE

July 12, 2022

Perpetua Resources Begins Investment in Water Quality Improvements at

Historic Mine Site

Idaho Governor Brad Little, members of the Idaho Congressional Delegation, and representatives from

local communities celebrate this milestone for abandoned mine site restoration.

BOISE, ID – Perpetua Resources Corp. (Nasdaq: PPTA / TSX: PPTA) (“Perpetua Resources” or “Perpetua”

or the “Company”) was joined today by community members, government officials and local business

leaders at a groundbreaking ceremony to mark the beginning of early cleanup activities and water

quality improvements to benefit the historic Stibnite mining district . After 100 years of mining activity,

the millions of tons of unconstrained tailings and mine waste left behind by previous operators has been

degrading water quality for decades. Today’s groundbreaking cere mony marked the start of a multi -

year, multi-million-dollar investment designed to improve environmental conditions at the historic site.

The first four-year phase of the project includes removing 325,000 tons of legacy waste and tailings away

from the river and rerouting streams to keep clean water clean. High-ranking elected officials from across

the state agree the work being done by Perpetua Resources is a model for private investment to help

address legacy environmental issues at historic mine sites.

“We did not cause the contamination that has

worsened water quality in the historic Stibnite

Mining District for decades, but we are part of

the solution,” said Laurel Sayer, CEO of

Perpetua Resources. “Today, we put our

commitments into action and are

demonstrating that when we work together, big

ideas can become reality. We are grateful for

the coordination of our state and federal

agencies who helped shape this visionary

solution to revive this historic mine site. We are

proud to bring much needed stewardship to

Idaho’s headwaters.”

Perpetua worked with the Environmental Protection Agency (“EPA”) and the United States Department

of Agriculture (“USDA”) for more than three years to receive permission to conduct time critical , early

action cleanup activities. After consultation with other interested parties, including the Idaho

Department of Environmental Quality, Perpetua Resources, the EPA and USDA signed an

Administrative Settlement Agreement and Order on Consent (“the Agreement”) in 2021 paving the

way for Perpetua to address legacy issues in key areas of the Stibnite district.

“Idaho’s natural resources can contribute a steady domestic supply of the materials we need to

advance our economy,” said Idaho Governor Brad Little. “At the same time, cle anup projects like you

see here at Stibnite are a critical part of the future of responsible mining in Idaho. Idaho has a rich

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history of collaborative work that balances economic prosperity with environmental stewardship.

Perpetua Resources is another great example of this responsible balance, and I applaud their efforts to

work with the respective agencies to make cleaning up the historic Stibnite mine site a reality.”

“I was pleased to see the EPA and USDA sign an agreement granting Perpetua Resources p ermission

to voluntarily clean up key areas by the historical Stibnite mine site,” said Idaho Congressman Mike

Simpson. “These time critical actions are long overdue and will focus on addressing the most

immediate needs to improve water quality. This work proves that Perpetua is committed to leaving the

abandoned mine site better than they found it. It is an important day for Idaho, we are all grateful to

Perpetua for taking on this work.”

“Water is one of Idaho’s most treasured resources,” said Idaho Congressman Russ Fulcher. “Today’s

announcement by Perpetua Resources shows the company shares this belief. By improving water

quality in the historic Stibnite mining district through voluntary cleanup activities, Perpetua is showing

the way for collaborative mining into the future.”

The groundbreaking ceremony involved sixty participants, including

the Director of the Idaho Department of Environmental Quality Jess

Byrne, Kimberly Glineski from the Idaho Department of Commerce,

Mayor of Cascade Judy Nisula, residents of the Village of Yellow Pine,

IMCO Construction CEO Taylor Kimberly, President and CEO of

Perpetua Resources Laurel Sayer and many others.

On the behalf of Idaho Congressman Russ Fulcher, Cascade Mayor,

Judy Nisula, presented Laurel Sayer with an American flag flown over

the U.S. Capitol Building to commemorate the historic moment. “On

behalf of our region, thank you for being good stewards of our

community, our state and our environment,” said Mayor Nisula.

Early Action, Voluntary Environmental Improvements

Mining in the historic Stibnite Mining District first started in 1899. Stibnite then gained national

significance during World War II when the U.S. Government commissioned antimony and tungsten

production from the site to help with the war effort. In fact, Stibnite produced the majority of both

minerals used by the U.S. during World War II and the U.S. Munitions Board credited the mine for

shortening World War II by a year and saving a million American lives.

Unfortunately, most of the mining that occurred at Stibnite took place long before modern protections

and regulations were established. As a result, the site was never fully reclaimed. Today, 10.5 million

tons of unlined tailings and waste leach arsenic and antimony into ground and surface water, the East

Fork of the South Fork of the Salmon River flows into an abandoned mining pit and habitat conditions

are degraded. Perpetua Resources has proposed a redevelopment plan to mine the site for gold and

the critical mineral antimony, while concurrently restoring the environment.

While the Stibnite Gold Project is currently under regulatory review, early cleanup actions are starting

now. Perpetua, the EPA and the U.S. Forest Service have worked together to develop a detailed scope

of work for Phase One cleanup activities since signing the Agreement in early 2021. IMCO

Construction was selected to oversee water quality improvements taking place this summer which will

include:

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• Lining, improving and rerouting stream channels on site to keep clean water from interacting

with old waste dumps on site

• Removing the Defense Minerals Exploration Administration legacy waste rock dump from within

and along a tributary to the East Fork of the South Fork of the Salmon River and restoring the

original streamflow course

For further information about Perpetua Resources Corp., please contact:

Chris Fogg

Investor Relations Manager

[email protected]

[email protected]

Mckinsey Lyon

Vice President External Affairs

[email protected]

Website: www.perpetuaresources.com

About Perpetua Resources and the Stibnite Gold Project

Perpetua Resources Corp., through its wholly owned subsidiaries, is focu sed on the exploration, site

restoration and redevelopment of gold-antimony-silver deposits in the Stibnite-Yellow Pine district of

central Idaho that are encompassed by the Stibnite Gold Project. The Project is one of the highest-

grade, open pit gold deposits in the United States and is designed to apply a modern, responsible

mining approach to restore an abandoned mine site and produce both gold and the only mined source

of antimony in the United States. Further advancing Perpetua Resources’ ESG and sust ainable mining

goals, the Project will be powered by the lowest carbon emissions grid in the nation and a portion of

the antimony produced from the Project will be supplied to Ambri, a US -based company

commercializing a low-cost liquid metal battery essential for the low-carbon energy transition. In

addition to the company’s commitments to transparency, accountability, environmental stewardship,

safety and community engagement, Perpetua Resources adopted formal ESG commitments which can

be found here.

Forward-Looking Information

Statements contained in this news release that are not historical facts are "forward-looking information" or "forward-

looking statements" (collectively, "Forward -Looking Information") within the meaning of applicable Canadian

securities legislation and the United States Private Securities Litigation Reform Act of 1995. Forward -Looking

Information includes, but is not limited to, disclosure regarding possible events, next steps and courses of action

including environmental clean up actions by us and our cont ractors; our ability to comply with and obtain permits

related to the Stibnite Gold Project; actions to be taken by the State of Idaho and other government agencies and

regulatory bodies; predictions regarding improvements to water quality and other enviro nmental conditions at the

site; reduction of the Project footprint and the anticipated benefits and other effects thereof; our and Ambri, Inc.’s

ability to perform under the supply agreement, which agreement is subject to certain conditions, including

identification of one or more refiners to transform our antimony concentrate into antimony metal, and mutual

agreement on certain material terms, including volume and pricing. In certain cases, Forward -Looking Information

can be identified by the use of words and phrases or variations of such words and phrases or statements such as

"anticipate", “expect” “plan”, “likely”, “believe”, “intend”, “forecast”, “project”, “estimate”, "potential", "could", "may",

"will", "would" or “should”. In preparing the Forward -Looking Information in this news release, Perpetua Resources

has applied several material assumptions, including, but not limited to, assumptions that the current exploration,

development, environmental and other objectives concerning the Stibnite Gold Project can be achieved and that its

other corporate activities will proceed as expected; that the review process under the NEPA (including any joint

review process involving the USFS, the State of Idaho and other agencies and regulatory bodies) as well as the public

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review process and SDEIS will proceed in a timely manner and as expected; and that all requisite information will

be available in a timely manner. Forward-Looking Information are based on certain material assumptions and involve

known and unknown risks, uncertainties and other factors which may cause the actual results, performance or

achievements of Perpetua Resources to be materially different from any future results, performance or achievements

expressed or implied by the Forward -Looking Informa tion. Such risks and other factors include those factors

discussed in Perpetua Resources' public filings with the U.S. Securities and Exchange Commission (the “SEC”) and

its Canadian disclosure record. Although Perpetua Resources has attempted to identify important factors that could

affect Perpetua Resources and may cause actual actions, events or results to differ materially from those described

in Forward -Looking Information, there may be other factors that cause actions, events or results not to be as

anticipated, estimated or intended. There can be no assurance that Forward -Looking Information will prove to be

accurate, as actual results and future events could differ materially from those anticipated in such statements.

Accordingly, readers should not place undue reliance on Forward -Looking Information. For further information on

these and other risks and uncertainties that may affect the Company’s business, see the “Risk Factors” and

“Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of the Company’s

filings with the SEC, which are available at www.sec.gov and with the Canadian securities regulators, which are

available at www.sedar.com. Except as required by law, Perpetua Resources does not assume any obligation to

release publicly any revisions to Forward -Looking Informati on contained in this news release to reflect events or

circumstances after the date hereof or to reflect the occurrence of unanticipated events.