A proof-of-concept detector prototype capable of collecting and storing radiometric data in Jet Boring System (JBS) pilot holes at the Cigar Lake uranium mine is presented. Variant design is used to design, develop, test and implement the detector's hardware, fi rmware and software. The battery powered detector is attached inside a JBS drill rod to collect radiometric data through the drilling cycle. A readout box is used to initiate the detector, recharge the battery and download radiometric data after a pilot hole drilling cycle is complete.

Functional testing results are presented and comparative test results between the JBS gamma probe and the AlphaNUCLEAR Hi-Flux probe are evaluated. Field data collected from three pilot holes is plotted against each pilot hole's driving layout and jetting recipe. Future work is discussed for use of Monte Carlo modelling and a high activity source to characterize the JBS gamma probe and achieve conversion of gamma counts into U₃O₈ grade.

Cigar Lake is the second highest known grade uranium mine in the world. The mine is located in northern Saskatchewan, Canada. Project engineers during the 2000 JBS proof-of-concept tests suggested that jetting parameters for extracting cavities at full production may be more eff ective if selected based on gamma logs and experience from adjacent cavities instead of using pre-set recipes and interim surveys during jetting. Moreover, in-situ pilot hole radiometric data may also be useful for grade control and grade reconciliation from a cavity-to-cavity basis. At present, there is no method available to efficiently and effectively obtain gamma logs from pilot holes, this project is a major first step to address this issue.