APPLYING SIX SIGMA TO THE CORRELATION OF REVERSE CIRCULATION TO CORE DRILLING RESULTS IN THE EXPLORATION OF PHOSHATE ORE IN SOUTHEAST IDAHO

Gamma log, assay and lithologic data were collected from 32 reverse circulation and 2 core drill holes at Monsanto’s Trail Creek Property located 15 miles northeast of Soda Springs, Idaho, during the 2003 summer field season. The tools of Six Sigma were applied to provide a rigorous examination of the data. Paired-T tests were used on two-twinned core holes for process control. The ability to correlate core drilling to reverse circulation provides an opportunity to save about $20 per foot per hole or $50K to $150K per season depending upon the size of the exploration program. Additionally, the opportunity to incorporate reverse circulation drilling into the exploration of phosphate, with improved confidence, will increase drill density, improve geologic confidence, reduce overall cost, and reduce the time required to evaluate the resource potential of a property.