Sentinel Metals Commences Maiden Extensional Drilling Campaign at Columbia Gold-Silver Project

Sentinel Metals (ASX: SNM) subsidiary company Great Plains Mining has drilled the first hole of a maiden extensional diamond campaign at its Columbia gold-silver project in the US.

The 21-hole, 5,000-metre program will target priority zones defined by recent geological reinterpretation, geophysical insights, and assay validation, as well as test new high-priority structural targets.

It will confirm and extend known zones of gold-silver mineralisation and test deeper feeder structures while assessing the broader scale of the brownfields project, which is located within a historically productive mining district.

North American contractor Corexplore Drilling Services has been engaged to conduct the campaign and has mobilised a state-of-the-art, small footprint, low-emission diamond rig featuring full water recycling and capture capabilities.

Approval to Proceed

Drilling follows an approval to proceed issued by the Montana Department of Environmental Quality (DEQ) for an amendment to the exploration licence held by Great Plains.

The DEQ determined that an environmental assessment was the appropriate level of review under the state’s Environmental Policy Act.

This cleared the way for a 15-day public comment period that saw Sentinel engage widely with local community members and stakeholders prior to the start of drilling.

In excess of 400 historical drill holes have been completed across the broader project area over the past century, providing Sentinel with a substantial dataset to support the identification of priority drill targets.

‘Compelling High-Priority Targets’

“Seeing the drill rig turning at Columbia is an enormously exciting moment for our team and shareholders who have backed this company with real patience,” managing director Matt Herbert said.

“Following significant work to validate historical data and refine our geological model, we have now begun testing what we believe are compelling high-priority targets across this project.”

Sentinel recently embarked on key environmental baseline studies at Columbia in parallel with ongoing exploration and technical activities.

The company engaged Westech Environmental to conduct winter wildlife monitoring as part of a broader, staged approach to environmental data collection and to complement baseline information collected at other times of the year.

The results will be integrated with existing environmental datasets and used to inform future exploration planning and longer-term permitting considerations.