KGHM and Pomerania sign letter of intent for Poland's first polyhalite mine, a 10 billion złoty project
KGHM Polska Miedź and the Pomeranian Voivodeship have signed a letter of intent for the 'Puck' project, aiming to build an underground polyhalite mine near the Bay of Puck. The deposit holds over 303 million tonnes of the mineral, used in low-chloride fertilisers.
The Puck project
KGHM Polska Miedź SA and the Pomeranian Voivodeship signed a letter of intent on 8 July 2026 in Gdańsk, launching the next phase of the 'Puck' project. The plan is to build Poland's first polyhalite mine, tapping the Mieroszyno deposit whose geological resources exceed 303 million tonnes. The investment is estimated at 10 billion złoty and would include an underground mine with two shafts reaching about 800 metres, a processing plant and surface infrastructure.
The letter of intent opens another stage of cooperation between KGHM Polska Miedź SA and the Pomeranian Voivodeship. Ahead of us is the preparation of documentation needed to apply for a mining concession.
Timeline and scale
Exploration in the Puck Bay area has been underway since 2014 under a potash-magnesium salt prospecting licence. The geological documentation for Mieroszyno was approved by the Minister of Climate and Environment in June 2025. KGHM's president, Remigiusz Paszkiewicz, said that preparing the documentation and obtaining environmental, administrative and concession decisions could take four to six years. Construction of the mine, including the shafts, may then require another eight to ten years.
I think that in 12 to 14 years we should start full exploitation of this site.
- KGHM begins exploration in the Puck Bay area under a potash-magnesium salt licence.
- Geological documentation of the Mieroszyno deposit approved by the Minister of Climate and Environment.
- Letter of intent signed between KGHM and the Pomeranian Voivodeship in Gdańsk.
- Expected completion of documentation, environmental decisions and mining concession.
- Target start of full polyhalite exploitation, 12–14 years after the letter of intent.
Local and environmental context
The letter of intent commits both sides to transparent development and dialogue with local stakeholders. Pomeranian marshal Mieczysław Struk stressed that the investment would be located in an environmentally and touristically sensitive area, and that social acceptance and the involvement of regional businesses would be critical.
This is a great opportunity, but also a responsibility, also for the local government administration. As shown by previous experiences from the preparation and implementation of other investments in our region, such as the construction of a nuclear power plant or offshore wind farms, the success of these activities depends on many factors, including social acceptance and the inclusion of Pomeranian enterprises.
Polyhalite's agricultural role
Polyhalite is a rare sulphate mineral that naturally contains potassium, magnesium, calcium and sulphur. Its low chloride content makes it suitable for sensitive crops such as fruits, vegetables and oilseeds. KGHM describes the project as one of the largest of its kind globally, with the potential to strengthen Poland's raw-material independence and food security.
