Rio Puerco Project

On August 27, 2025, North Shore announced that it had entered into the Rio Puerco Option Agreementwith Resurrection Mining LLC for the Rio Puerco uranium project (“Rio Puerco” or the “Project”), located approximately 60 km northwest of Albuquerque in northwestern New Mexico, USA. After satisfying certain conditions by August 27, 2030, North Shore has the right to acquire up to a 100% interest in the Project. (the “Transaction”). The details of the Transaction are outlined in an August 24, 2025 news release.

Rio Puerco Transaction and Project Highlights

• A historical resource estimate of 6.0 million tonnes at an average grade of 0.09% eU₃O₈ for 11.4 million lbs. of U₃O₈ reported in 2009 and 2011 (the “Historical Resource”)¹
• Kerr-McGee Corporation (“Kerr-McGee) began development of an underground uranium mine at Rio Puerco in the 1970s, but activity ceased in the early 1980s after a trial mining phase due to low uranium prices
• Substantial historical dataset to guide and optimize exploration programs, Kerr-McGee drilled over 1,100 exploration holes at Rio Puerco in the 1960s and 1970s
• Preliminary review of historical data suggests the potential for In-Situ Recovery (“ISR”) mining, the lowest cost method for producing uranium
• Located in the Grants Uranium District, the largest producer of uranium in the United States with over 340 M lbs. of U₃O₈ produced, and near two significant active uranium projects, Marquez-Juan Tafoya (Anfield Energy Inc.) and Cebolleta (Premier American Uranium Inc.)
• Strong US government support for nuclear power and uranium mining projects and a stated objective to reduce reliance on foreign nuclear fuel
  • Executive Orders issued by President Trump on May 23, 2025 include a call for quadrupling US nuclear capacity by 2050, accelerating new reactor development, strengthening the US nuclear fuel supply chain and reforming the US regulatory environment
  • On October 28, 2025, Cameco Corporation and Brookfield Asset Management announced a strategic partnership with the US government that would support nuclear reactor development in the USA and elsewhere.
• Staged earn-in structure allows the Company to optimize exploration programs
• North Shore is now planning for a drill program, currently scheduled for May 2026, aimed at validating the Historical Resource and expanding the uranium mineralization footprint at Rio Puerco, see February 23, 2026 news release

¹ The Historical Resource has not been verified. It is a historical estimate and not current and does not comply with Canadian NI 43-101 guidelines for the reporting of Mineral Resources. A qualified person has not verified the Historical Resource on behalf of the Company and North Shore has completed no work programs at Rio Puerco. Though not current, the Company views the Historical Resource estimates as reliable and sufficient to justify the initiation of work programs aimed at validating and potentially expanding upon the estimates. There is no guarantee that the work programs envisioned by North Shore will ultimately result in the definition of NI 43-101-compliant resources.

Rio Puerco Location Map, New Mexico. Roca Honda (Energy Fuels), Marquez-Juan Tafoya (Anfield Energy) and Cebolleta (Premier American Uranium) are advanced exploration/development stage uranium projects.

Rio Puerco mine shaft, built in the 1970s by Kerr-McGee to access uranium ore at approximately 260 m depth

Proposed drill site in North Shores 2026 Rio Puerco drill program

Rio Puerco surveyed claim corner marker