RC Drilling - The Benefits
Advantages of Reverse Circulation Drilling
Compared to core drilling, RC drilling with inherently faster penetration rates provides several benefits:
- Direct drilling cost reductions in the range of 25% to 40%.
- Faster completion of drill programs with quicker delivery of results.
- Reduced man-hours at the drill with decreased exposure to potential accidents.
- Reduced contractor activity in the mine reduces mine support burden.
- Indirect cost reductions gained from a simplified sampling process.
- Requires less water than diamond drilling.
RC samples are collected at the drill and sent directly to the assay lab. Unlike diamond drill core, which is generally logged, photographed, split for sample, assayed and warehoused, RC sampling requires much less handling resulting in faster assay turnaround with accompanying cost reductions. Larger volume RC samples often give more representative gold samples than split half core samples.
There are however some cons to RC drilling
- Less geological information from sample.
- Holes can deviate (Spiral Stabiliser Subs keep holes straighter)
- Diamond can usually drill to greater depth although depths up to 800m have been achieved with RC Drilling.
Comparative cost of Exploration Program and Budget for a standard project in 2011
Follow-up exploration will be staged and conducted over a 12 to 24 month period and should include but not be limited to:
- A total of 5,000 soil and rock samples collected across the property;
- Prospecting and mapping over the newly granted tenements;
- A 10 hole combined RC and diamond drill program in 2011 to test the continuity and extent of gold mineralization intersected during 2008 at the Wealth of Nations Prospect;
- To test a number and variety of quality gold in soil anomalies specific target areas;
- A number of RC or diamond drill holes are required to test the airborne and subsequent ground EM targets identified in association with surface gold at the target areas.
The estimated cost to conduct the surface sampling program is $AUD500,000. Proposed At an all up cost of approximately $AUD 120 per metre for 12,500 metre of RC drilling and $200 per metre for 2,250 metres of diamond drilling, it is anticipated that the drilling program will cost up to approximately $AUD 2,000,000 to complete. The program will be staged and conducted over a 12 to 24 month period.