All Samples Met or Exceeded Strength Criteria for Primary Mining Method
VANCOUVER, BC / ACCESS Newswire / July 6, 2026 / Grande Portage Resources Ltd. (TSXV:GPG)(OTCQX:GPTRF)(FSE:GPB) ("Grande Portage" or the "Company") is pleased to provide a project update for the New Amalga Gold property near Juneau, Alaska.
The company has received laboratory results for preliminary backfill strength testing of CRF (cemented rockfill) samples which were cast using material sourced from core samples drilled during previous field seasons. The waste rock lithologies in these samples were selected to be aligned with those that will be encountered during mine development as well as those which would be present in ore sorter reject material.
These samples were cast into test cylinders using a 4% cement binder content (see pictures below) and were tested for uniaxial compressive strength (UCS) after 10-day and 17-day cure times.
All samples met or exceeded the preliminary strength criteria selected for overhand longhole stoping, the primary mining method planned for New Amalga. Based on these results, the company intends to advance both the waste rock from mine development as well as the ore sorter reject rock as feedstocks for making CRF backfill.
