Prediction of acid rock drainage using field-based testing tools

Abstract

Tests currently used by the industry for acid rock drainage (ARD) prediction heavily utilize static geochemical tests. Instead, effective tools which allow for early domaining should be utilized as they can be performed on a greater number of samples, allowing for deposit-wide environmental characterization. These must be simple enough to perform in the core shed or field-laboratory to keep cost and turn-around time to a minimum. Simple field-based pH tests and chemical staining should be performed. In addition, mineralogical characterization methods for drill core materials i.e., an ARD focused logging code and the use of portable instruments (i.e., pXRF, Equotip) should be pursued. This chapter presents several field tools appropriate for ARD prediction. These tools were developed, tested and validated using drill core and waste rock materials obtained from several Australian mines with differing geology, mineralogy and mineralization style. This chapter demonstrates that by utilizing these field based tests, industry has the opportunity to achieve: (i) effective ARD prediction testwork; (ii) detailed deposit-wide characterization, (iii) development of best practice waste management plans; and (iv) identification of the most suitable rehabilitation options.