PolyMet taps Denton Henkelman as vice president and project manager

St. Paul, Minnesota, June 30, 2022– PolyMet Mining Corp. TSX: POM; NYSE American: PLM, today announced the appointment of Denton Henkelman as vice president and project manager.

During a 36-year career, Mr. Henkelman led the engineering and construction of major hard rock mining projects, including the Eagle nickel-copper mine in Michigan, the Diavik diamond mine in the Northern Territories -Western Canada, iron ore expansion, oil sands development and ancillary facilities such as refineries, shipping ports, water management systems and railways globally . Most recently, Mr. Henkelman was project manager for Baffinland Iron Mines Corp.’s major iron mine expansion. in the Canadian Arctic.

“Denton brings to PolyMet a deep and extensive experience in engineering and construction management, having led or contributed significantly to the development of some of the world’s most advanced hard rock mines. We are thrilled to have him on our team,” said Jon Cherry, Chairman, President and CEO.

Mr. Henkelman’s project development portfolio includes Rio Tinto’s Yarwun II alumina refinery project in Queensland, Australia, Cleveland Cliffs’ Bloom Lake Iron Ore mine expansion in northern Quebec, Canada, and OPTI Canada Inc.’s Long Lake Phase I oil sands upgrader located near Fort McMurray, Alberta.

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About PolyMet

PolyMet is a mining development company that owns 100% of the NorthMet project, the first large-scale project to receive permits in the Duluth complex in northeast Minnesota, one of the major undeveloped mining regions in the world. NorthMet has significant proven and probable reserves of copper, nickel and palladium – metals critical to improving infrastructure and global carbon reduction efforts – in addition to marketable reserves of cobalt, platinum and gold . When operational, NorthMet will become one of the leading producers of nickel, palladium and cobalt in the United States, providing a much needed and responsibly mined source of these critical and essential metals.

Located in the Mesabi Iron Range, the project will provide economic diversity while leveraging the region’s established supplier network and skilled workforce and will generate a level of business that will have a significant effect on the local economy. For more information: www.polymetmining.com.

For more information, please contact:

Media

Bruce Richardson, Corporate Communications

Such. : +1 (651) 389-4111

[email protected]

Investor Relations

Tony Gikas, Investor Relations

Tel: +1 (651) 389-4110

[email protected]

PolyMet Disclosures

This press release contains certain forward-looking statements regarding anticipated developments in PolyMet’s operations in the future. Forward-looking statements are frequently, but not always, identified by words such as “expects”, “anticipates”, “believes”, “intends”, “estimates”, “potential”, “possible”. , “projects”, “plans”, and similar expressions, or statements that events, conditions or results “will”, “could”, “could” or “should” occur or be achieved or their negative or other comparable words.These forward-looking statements may include statements regarding ability to receive environmental and operating permits, job creation and effect on the local economy, or other statements that do not are not statements of fact. Forward-looking statements address future events and conditions and therefore involve inherent known and unknown risks and uncertainties. Actual results may differ materially from those in the forward-looking statements due to risks a which PolyMet is faced with or due to actual facts that differ from the assumptions underlying its forecasts.

PolyMet’s forward-looking statements are based on the beliefs, expectations and opinions of management as of the date the statements are made, and PolyMet undertakes no obligation to update any forward-looking statements if the circumstances or beliefs, Management’s expectations and opinions were to change.

Specific reference is made to the risk factors and other considerations underlying the forward-looking statements discussed in PolyMet’s most recent Annual Report on Form 40-F for the fiscal year ended December 31, 2021, and in our other filings with the authorities. Canadian Securities and US Securities and Exchange Commission.

The annual report on Form 40-F also contains the company’s mineral resources and other data, as required by National Instrument 43-101.

No regulatory authority has reviewed or accepted responsibility for the adequacy or accuracy of this release.