Hemlo Mining Corp. Reports Underground Electrical Substation Outage; Mine-Wide Operations Continue

Hemlo Mining Corp. Reports Underground Electrical Substation Outage; Mine-Wide Operations Continue PR Newswire TORONTO, Sept. 14, 2026 TORONTO, Sept. 14, 2026 /PRNewswire/ -- Hemlo Mining Corp. (TSX: HMMC) (OTCQX: HMMCF) ("Hemlo Mining" or the "Company") reports that an underground electrical substation (the "Substation") servicing a portion of underground mining operations at the Hemlo Gold Mine ("Hemlo Mine" or the "Mine") experienced a temporary electrical outage on September 4, 2026. The affected Substation supplies power to a portion of the Alimak production area on the 9765 level of the Mine, where the Company was advancing ongoing production and ramp-up activities. There were no injuries associated with the outage and all personnel underground at the time were safely brought to surface. Mining and processing in all other areas of the Mine, including the processing plant, are unaffected and continue to operate normally. In the days following the outage, the Company completed a comprehensive assessment of the affected infrastructure and potential operational impact. Technical and operating teams are actively advancing repair and expedited replacement plans for the Substation. A temporary electrical bypass system has been established, which has restored power to the affected area at reduced capacity. The bypass system allows certain mining activities to continue while development and exploration activities remain limited until full power is restored. As part of the Company's critical spare parts audit, a replacement Substation had previously been ordered, with delivery expected in December 2026 at an estimated cost of approximately US$250,000. In the interim, the Company is pursuing several additional measures, including expedited equipment procurement, backup power options, and the potential relocation of electrical infrastructure from other areas of the Mine, with the objective of accelerating the restoration of full power to the affected area. The outage and resulting reduction in available power may result in the deferral of mining from certain planned stopes until full power is restored. The affected area remains accessible and production continues across the remainder of the Mine without interruption. To mitigate potential production impacts, the Company is evaluating alternative mine sequencing and accelerating development and mining activities in other areas of the operation. Jason Kosec, President, CEO & Director of Hemlo Mining, commented: "Over the past week, our site teams have responded quickly and professionally to assess the impact of the outage, which is limited to a single area of the Mine. Our first priority was the safety of our workforce, and I am pleased to report that there were no injuries associated with the outage and that all safety protocols were followed. The work of our team has allowed us to establish a temporary electrical configuration that supports certain activities in the affected Alimak area while we continue to advance several solutions aimed at restoring full production capability. We are also evaluating opportunities to resequence work into other areas of the Mine to maintain planned production, development, and exploration activities. With more than 300 kilometres of existing mine development and multiple active mining areas, the Hemlo Mine has significant operational flexibility, allowing processing operations to continue without interruption while mitigation efforts advance." About Hemlo Mining Corp. Hemlo Mining Corp. is a Canadian gold producer focused on operating and enhancing the Hemlo gold camp in northwestern Ontario. The Company's flagship asset, the Hemlo Gold Mine, has produced approximately 25 million ounces of gold since 1985 from both underground and open pit operations. The Company's fit-for-purpose strategy is centered on maximizing the value of the mine through improved operating efficiency, production growth, and mine life extension. Hemlo Mining is led by an experienced team with a track record of value creation in the global mining sector. Forward-looking Statements This document contains certain forward-looking information and forward-looking statements within the meaning of applicable securities legislation (collectively, "forward-looking statements"). The use of words such as "expects", "estimates", "anticipates", "plans", "will", "may", "should" and similar expressions is intended to identify forward-looking statements. Forward-looking statements contained in this news release include statements regarding: the expected delivery of the replacement Substation in December 2026; the assessment, timing, extent and effectiveness of repair, replacement, bypass, mine resequencing and other mitigation measures; the sourcing of alternative replacement equipment; the potential deferral of mining from certain planned stopes; the Company's previously planned production ramp-up in the Alimak area; the continuity of mining and processing activities in areas of the Mine other than the affected stopes; and the ultimate effect of the disruption and mitigation measures on 2026 production. These forward-looking statements are provided as of the date of this news release and reflect predictions, expectations or beliefs regarding future events based on the Company's beliefs at the time the statements were made, as well as various assumptions made by and information currently available to the Company. In making the forward-looking statements included in this news release, the Company has applied several material assumptions, including, but not limited to: the accuracy of the current technical assessment of the affected area; the availability of labour, equipment, materials and replacement components; the ability to implement temporary power, repair and mine resequencing measures as contemplated; the ability to accelerate development and mining in alternative areas; the continuity of operations in unaffected areas; the timing of delivery and installation of the replacement Substation; and that there will be no additional material disruptions affecting the Hemlo Gold Mine. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated. The Company cautions readers not to place undue reliance on forward-looking statements. Forward-looking statements involve significant known and unknown risks and uncertainties that could cause actual results to differ materially from those anticipated, including delays in, or unsuccessful implementation of, repair or mitigation measures; further equipment failures; changes in mine sequencing, grades, tonnes, recoveries or production schedules; supply chain delays; the availability of contractors and replacement components; health, safety and environmental risks; and the risks and uncertainties set forth in the section entitled "Risk Factors" in the Company's Annual Information Form for the year ended December 31, 2025 filed with the applicable Canadian securities regulatory authorities on April 15, 2026. Except as required by the securities disclosure laws and regulations applicable to the Company, the Company undertakes no obligation to update forward-looking statements if management's beliefs, estimates or opinions, or other factors, should change. View original content to download multimedia:https://www.prnewswire.com/news-releases/hemlo-mining-corp-reports-underground-electrical-substation-outage-mine-wide-operations-continue-302878036.html SOURCE Hemlo Mining Corp. Contact: Contact Information: Jason Kosec, President, CEO & Director, +1 (250) 552-7424; Jonathan Awde, Executive Chair, +1 (604) 761-5251; General Inquiries: [email protected]