Riversgold Ltd (ASX:RGL, FRA:RGV, OTC:RVSGF) has reported positive outcomes from technical studies supporting mining permit applications for the Northern Zone Gold Project near Kalgoorlie, with no material geotechnical, groundwater or acid mine drainage risks identified.
The results advance preparation of the project’s Native Vegetation Clearing Permit and Mine Development and Closure Proposal, which are required before mining operations can begin at the proposed open pit development, 25 kilometres east of Kalgoorlie in Western Australia.
Riversgold technical director Edward Mead said the results represented an important step towards securing the approvals needed to begin mining.
“To have these final reports back on soils, geotechnical and water studies for our Kalgoorlie Gold Project, showing no material issues is a great result,” Mead said.
“We continue to get much closer to breaking ground at Northern Zone.”
Technical studies support open pit development
Consultant ResourcesWA has completed soil, waste, geotechnical and hydrogeological assessments for Northern Zone, with the findings supporting the proposed mine design.
Waste rock was found to be predominantly non-acid forming, with low sulphur content and substantial acid-neutralising capacity. This indicates minimal risk of long-term acid mine drainage.
Geotechnical assessments also concluded that the proposed waste dump design had high factors of safety and a very low probability of failure.
Pit slopes were validated at bench and inter-ramp scales, with factors of safety above 1.33, supporting the stability of the proposed open pit configuration.
Groundwater risks considered manageable
Hydrogeological investigations identified an average water table depth of about 37 metres below surface and low permeability across the project area.
The findings indicate groundwater inflows are unlikely to create a material operational or geotechnical risk.
Flood modelling is continuing, although preliminary work suggests only minor culvert infrastructure may be required along project access routes.
Permit applications nearing submission
Preparation of the Native Vegetation Clearing Permit application is in its final stages, with submission expected in the coming weeks once minor outstanding inputs have been incorporated.
The Mine Development and Closure Proposal is around 60% complete and remains on schedule for submission to the Western Australian Department of Mines, Petroleum and Exploration.
Next steps
Riversgold will finalise and submit the Native Vegetation Clearing Permit application before completing the remaining work on the Mine Development and Closure Proposal.
The company will also continue flood modelling and incorporate the final technical inputs into its permitting documentation as it moves Northern Zone closer to development.