Mr. Ian Klassen reports

GRANDE PORTAGE RESOURCES ADVANCES ONGOING PROJECT STUDIES AND FIELDWORK TO SUPPORT NEW AMALGA GOLD PROJECT DEVELOPMENT

Grande Portage Resources Ltd. has provided a project update for the New Amalga gold property near Juneau, Alaska.

In addition to the 2026 drill program, numerous engineering studies and environmental fieldwork programs are in progress utilizing several industry-leading consulting firms, most of which are based in Alaska. These activities provide key inputs for the environmental review and permitting process, which the company will initiate with the state and federal regulatory agencies to enable development of the mining operation.

Current and planned activities for the 2026 field season include the following.

Access road design -- Respec (Anchorage, Alaska/Juneau, Alaska)

Engineering design and geotechnical surveys for the access road for which the company is currently applying for an easement from the State of Alaska: This initial road segment is located on state land and construction can be initiated without federal permitting, with a near-term benefit of establishing a drilling materials staging area and helicopter landing pad much closer to the project site compared with current facilities in Juneau.

Aquatic studies -- Alaska Department of Fish & Game (Juneau, Alaska)

Continuation of field surveys and sampling to document aquatic biological conditions in the project area are necessary to inform future ADF&G fish habitat permits and other state and federal permits as well as to support mine design protective of fish habitat and fish passage. This work will be conducted by the Alaska Department of Fish & Game under contract with Grande Portage.

Climate assessment -- Stantec Consulting Services (various locations)

Evaluation of current and potential future climate conditions in the project area which will define engineering and environmental criteria for snowfall, precipitation events and other factors: This will influence the design of the facilities and associated environmental controls as well as inform the federal NEPA (National Environmental Policy Act) environmental review process.

Archeological and cultural resource surveys -- Stephen R. Braund & Associates (Anchorage, Alaska)

Extensive field surveys are planned to identify any historical or archeological and cultural sites in proximity to the project to comply with the Alaska Historic Preservation Act and Section 106 of the National Historic Preservation Act (NHPA).

Avian and wildlife surveys -- Stantec Consulting Services (Wasilla, Alaska)

Identifying nesting and habitat areas for eagles, goshawks and marbled murrelets as well as surveys for terrestrial wildlife such as mountain goats, utilizing a combination of aerial surveys, foot surveys, and automated sensors such as microphones and game cameras: This work will inform the federal NEPA process in addition to federal and State of Alaska permits.

Geochemical characterization and backfill testing -- Stantec Consulting Services (Denver, Colo.)

Test work on New Amalga core samples representing all major rock types present at the deposit to determine whether any have the potential to be reactive (acid generating or metals leaching) over the long term: Previous limited test work conducted in 2020 to 2021 on a small number of New Amalga wallrock samples showed favourable preliminary results, demonstrating significant net-acid-neutralizing potential ratios with all samples tested. Testing will also be performed on crushed and cemented drill core samples to determine the strength and geochemical characteristics of the proposed mine backfill (cemented rock fill), which would be produced using New Amalga development rock and ore sorter rejects.

Geohazard surveys -- Stantec Consulting Services (various locations)

Evaluation of the project area to identify potential risk zones for avalanches, landslides, floods, seismic events and other hazards will inform the placement and design of mine infrastructure as well as provide important inputs to the regulatory process.

Meteorological station construction -- Boreal Services (Anchorage, Alaska)

Construction of two meteorological stations to enable collection of weather data, including temperature, precipitation, wind, solar gain, relative humidity and ambient dust levels: These data are important for the engineering design of mine infrastructure and provides key inputs needed to apply for an Alaska Department of Conservation air quality control permit. A special-use permit has been acquired from the U.S. Forest Service and construction work will be undertaken over the summer.

Recreation assessment -- McKinley Research Group (Anchorage, Alaska/Juneau, Alaska)

Assessment of existing public recreation use of the area around the project will inform the NEPA environmental review and ensure the project plan is protective of recreational infrastructure such as trails and campsites.

River flow instrumentation -- Brailey Hydrologic LLC (Anchorage, Alaska)

Installation of gauging instrumentation on the Herbert River within the project area will enable measurements of river flow volume to inform the design of mine facilities and future Alaska Department of Conservation APDES (Alaska pollutant discharge elimination system) permit applications. Preliminary installation was completed during May, 2026, with data uplink integration with the planned nearby meteorological station planned for completion later this summer.

Sensitive, rare and invasive plant surveys -- Stantec Consulting Services (Wasilla, Alaska)

These surveys will identify plant species that may require protective mitigations in line with U.S. Forest Service management plans as well as any invasive species present in the project area that may require measures to prevent spreading during construction and operations.

Traditional and subsistence uses research -- Stephen R. Braund & Associates (Anchorage, Alaska)

This will include a detailed literature review of traditional and current subsistence use of the project vicinity, including consultation and outreach to tribal governments and Alaska native corporations. Interviews are intended to address cultural resources (for example, camps, cabins, trails, burial sites, indigenous place names) as well as current and traditional subsistence uses in and near the project area.

Surface water sampling -- Nortech Engineering (Juneau, Alaska)

Continuation and expansion of a multiyear analysis of water quality both upstream and downstream of the potential mine facilities provides a preconstruction baseline for future APDES permitting.

Traffic surveys and highway studies -- Respec (Anchorage, Alaska)

These studies will include vehicle-count surveys of baseline traffic conditions along Glacier Highway in the project area, modelling and assessment of the project's impact to traffic conditions, and evaluation of road and bridge conditions for the trucking of mined material to the barge dock location.

Wetlands and soils delineation -- Stantec Consulting Services (Wasilla, Alaska)

Mapping the extent of wetlands and other potentially jurisdictional waters in the project area is a key input for the design of mine facilities to avoid and minimize impacts to jurisdictional waters of the U.S. regulated under the Clean Water Act. This year's phase 2 work will cover remaining project areas not included in last year's phase 1 delineation and will inform the design of the mine surface layout as well as future Clean Water Act Section 404 permitting with the U.S. Army Corps of Engineers.

Ian Klassen, president and chief executive officer, commented: "We are excited to be moving forward with this extensive roster of project studies and field surveys as we advance the New Amalga project towards the state and federal regulatory review process. The firms we've selected are all leaders in their respective fields, with a large proportion of the work being done by Alaska-based teams with extensive experience operating in the region."

Project summary

The New Amalga gold project is located only 25 kilometres from Alaska's capital city of Juneau and six kilometres from paved highway. The resource remains open to expansion in multiple directions and hosts an indicated resource of 1,438,500 ounces of gold at an average grade of 9.47 grams per tonne gold (4,726,000 tonnes) and an inferred resource of 515,700 ounces of gold at an average grade of 8.85 grams per tonne gold (1,813,000 tonnes).

The current development concept, as described in the preliminary economic assessment (PEA) study with an effective date of Feb. 11, 2026, envisions a small-footprint underground mining operation that would transport material off site for processing by a third party, eliminating the need for an on-site gold recovery plant or tailings storage facility.

This set-up is designed to provide several benefits:

• Eliminates the need to build a gold recovery plant, minimizing mine footprint and power requirements and reducing project construction capex (capital expenditure);
• Eliminates the need to develop a tailings disposal facility at the site as no tailings would be generated;
• Removes the need for permanent waste rock storage facilities; waste rock generated from mine development would be returned to the underground workings as stope backfill;
• No use of chemical reagents for gold processing at the site;
• Dramatically reduces land usage and overall environmental footprint;
• Greatly facilitates postmining closure and reclamation;
• Simplifies the environmental review and permitting process.

Project summary

The New Amalga gold project is located only 25 kilometres from Alaska's capital city of Juneau and six kilometres from paved highway. The resource remains open to expansion in multiple directions and hosts an indicated resource of 1,438,500 ounces of gold at an average grade of 9.47 grams per tonne gold (4,726,000 tonnes) and an inferred resource of 515,700 ounces of gold at an average grade of 8.85 g/t Au (1,813,000 tonnes) (with an effective date of July 17, 2024).

The current development concept envisions a small-footprint underground mining operation which would transport material off site for processing by a third party, eliminating the need for an on-site gold recovery plant or tailings storage facility.

This set-up is designed to provide several benefits:

• Eliminates the need to build a gold recovery plant, minimizing mine footprint, power requirements and reducing project construction capex (capital expenditures);
• Eliminates the need to develop a tailings disposal facility at the site as no tailings would be generated;
• Removes the need for permanent waste rock storage facilities; waste rock generated from mine development would be returned to the underground workings as stope backfill;
• No use of chemical reagents for gold processing at the site;
• Dramatically reduces land usage and overall environmental footprint;
• Greatly facilitates postmining closure and reclamation;
• Simplifies the environmental review and permitting process.

Project highlights:

• A 100-per-cent interest in the New Amalga gold project, located near infrastructure only 25 kilometres north of Juneau, Alaska, and six kilometres from paved all-season highway;
• The property is host to at least eight large, long, gold-bearing mesothermal veins;
• 240 drill holes from 55 platforms totalling approximately 65,000 metres confirm a large gold-quartz system;
• Past drilling produced multiounce assays on several veins; select samples include:
  • Deep Trench vein: 15.3 m grading 37.1 g/t Au, 8.3 m grading 58.6 g/t Au and 11.6 m grading 28.3 g/t Au;
  • Goat vein: 2.1 m grading 74.2 g/t Au and 6.3 m grading 15.7 g/t Au;
  • Main vein: 3.1 m grading 79.2 g/t Au, 2.1 m grading 37.2 g/t Au and 3.1 m grading 13.9 g/t Au;
  • Ridge vein: 1.5 m grading 43.0 g/t Au and 1.5 m grading 29.2 g/t Au;
  • Sleeping Giant vein: 2.1 m grading 15.4 g/t Au and 3.2 m grading 20.7 g/t Au;
• The company's updated National Instrument 43-101 mineral resource estimate (MRE) with an effective date of July 17, 2024, reported an indicated resource of 1,438,500 ounces of gold at an average grade of 9.47 g/t Au (4,726,000 tonnes) and an inferred resource of 515,700 ounces of gold at an average grade of 8.85 g/t Au (1,813,000 tonnes) as well as an indicated resource of 891,600 ounces of silver at an average grade of 5.86 g/t Ag (4,726,000 tonnes) and an inferred resource of 390,600 ounces of silver at an average grade of 7.33 g/t Ag (1,813,000 tonnes);
• The deposit is open to the north, south and at depth;
• Goat vein surface outcrop channel samples assayed 129.02 g/t Au (3.76 ounces per ton) and 290 g/t Au (8.46 ounces per ton) with 224 g/t Ag (6.53 ounces per ton);
• Lidar survey of property discovered numerous targets -- the first of these tested confirmed gold discovery;
• Received excellent metallurgical recoveries up to 98.2 per cent;
• Completed more than six years of environmental baseline water sampling;
• Current development strategy envisions a small-footprint underground mining operation with third party off-site processing, eliminating the need for an on-site mill or tailings storage facility; this configuration reduces capital costs, greatly minimizes the project's environmental footprint and facilitates permitting;
• LOI (letter of intent) signed with Goldbelt Inc. (an Alaska native corporation organized under the Alaska Native Claims Settlement Act) for development of an ore export terminal at Cascade Point, Goldbelt's privately held parcel located only 22 kilometres from the project site.

Kyle Mehalek, PE, is the qualified person within the meaning of NI 43-101 and has reviewed and approved the technical disclosure in this release. Mr. Mehalek is independent of Grande Portage within the meaning of NI 43-101.

About Grande Portage Resources Ltd.

Grande Portage Resources is a publicly traded mineral exploration company focused on advancing the New Amalga mine project, the outgrowth of the Herbert gold discovery situated approximately 25 kilometres north of Juneau, Alaska. The company holds a 100-per-cent interest in the New Amalga property. The New Amalga gold system is open to length and depth and is host to at least six main composite vein-fault structures that contain ribbon structure quartz-sulphide veins. The project lies prominently within the 160-kilometre-long Juneau gold belt, which has produced over eight million ounces of gold.

The company's updated NI 43-101 mineral resource estimate (MRE) reported at a base-case mineral resources cut-off grade of 2.5 g/t Au and consists of an indicated resource of 1,438,500 ounces of gold at an average grade of 9.47 g/t Au (4,726,000 tonnes) and an inferred resource of 515,700 ounces of gold at an average grade of 8.85 g/t Au (1,813,000 tonnes) as well as an indicated resource of 891,600 ounces of silver at an average grade of 5.86 g/t Ag (4,726,000 tonnes) and an inferred resource of 390,600 ounces of silver at an average grade of 7.33 g/t Ag (1,813,000 tonnes). The MRE was prepared by Dr. David R. Webb, PhD, PGeol, PEng (DRW Geological Consultants Ltd.), with an effective date of July 17, 2024. Additional information on the New Amalga mine project is available in the technical report titled "Technical Report of the Herbert Gold Property, Juneau District, Southeast Alaska," dated July 17, 2024, which is available under Grande Portage's SEDAR+ profile.

We seek Safe Harbor.