Understanding the Columbia Gold and Silver Project
"At this stage, the work is limited to collecting geological and environmental data to understand the mineral deposit. This is not a proposal to build or operate a mine."
About the Project
Sentinel Metals is in the exploration phase of the Columbia Gold and Silver Project, located approximately 8 miles east of Lincoln on private land near Seven-Up Pete Gulch, aiming to gather geological and environmental data to inform future decisions.
To support this work, Sentinel has applied to the Montana Department of Environmental Quality (DEQ) for an amendment to its exploration license, which would permit 21 additional small-diameter (HQ) drill holes to supplement the more than 400 historical drill holes already on the property, ensuring regulatory oversight and transparency.
These activities are temporary, low-impact, and regulated to ensure environmental safety and minimize disturbance by using existing trails and previously impacted areas wherever possible.
Core Objectives
- circleGeological data collection and subterranean mapping.
- circleEstablishment of environmental baseline metrics.
- circleTransparent community and stakeholder engagement.
What This IS
- A data collection effort to understand geology and environmental conditions
- A limited exploration program using small-diameter drill holes
- A regulated activity under Montana law with DEQ oversight
- A temporary phase that informs future decision-making
What This IS NOT
- A mining proposal
- Approval for mineral extraction or commercial activity
- A construction project
- A decision about future development
Any potential mine would require a separate, multi-year permitting process, including additional environmental review and public input.
Low Impact Framework
All exploration work is being conducted under a low-impact framework that prioritizes maintaining existing environmental conditions.
Drilling operations use closed-loop systems, meaning water is contained, reused, and not discharged on-site. Drill locations are temporary and reclaimed after final use. Access is limited to existing roads and disturbed areas, wherever possible, to avoid unnecessary impacts on vegetation and potential wildlife habitat.
Closed-Loop
Water reuse with no intentional discharge.
Reclamation
Sites restored after temporary use.
Our Stewardship Commitments
Exploration work conducted under a low-impact framework minimizes environmental impact & protects local ecosystems.
Use of closed-loop systems where water is contained, reused, and not intentionally discharged on site.
Temporary drill locations that are systematically reclaimed to their natural state after final use.
Prioritizing the use of existing roads and disturbed areas.
Transparent, ongoing dialogue with Lincoln residents and Montana regulators.
Baseline Studies
Alongside exploration drilling, Sentinel is currently conducting baseline environmental monitoring programs. While not all of this work is required at the exploration stage, it is a critical step in understanding existing conditions before making any future decisions.
Current and upcoming 2026 activities include:
This year’s baseline work focuses on environmental, technical, and community-focused monitoring to support informed decisions. Each activity is designed to add clarity while minimizing site impact.
Biological Surveys
Seasonal monitoring of local fish, including eDNA, macroinvertebrates, wildlife, birds, reptiles, vegetation, and wetlands.
Technical Monitoring
Standard collection of meteorological, surface water, water flow, groundwater, and soil data for Acid-Base Accounting and geochemistry information.
Infrastructure Assessments
Routine tracking of local traffic and ambient noise levels.
What Happens Next?
Approval of the exploration license amendment would allow ONLY additional data collection. Any future decision about whether a mine could be proposed would:
Occur years down the line
Require a separate and comprehensive permitting process
Include additional environmental review
Provide opportunities for public input and transparency
Latest Documents
Sentinel Metals Public Comment on Draft EA-Exploration License No. 00816, Amendment 2 (Columbia Gold and Silver Project)
Exploration activities are conducted in accordance with Montana DEQ permits and Sentinel Metals’ internal environmental protocols. While every effort is made to minimize impact, mineral exploration is a dynamic process; descriptions of planned activities reflect our design intent and current operational standards.