In situ measurements and monitoring for rock wastes
Symposium Rouyn-Noranda 2002
Waste rock piles from metal mining operations are often comprised of large surface deposits of unsaturated, coarse grained soil and rock. The unsaturated condition and coarse grained nature of these deposits often make them difficult to monitor or characterise. Some of the key parameters that must be evaluated include; volume-mass relationships (e.g. water content, air content, porosity, density, degree of saturation, grain-size), transport properties (e.g. air-permeability, gas diffusion rates, hydraulic conductivity), geochemistry (e.g. solids, gas, and fluid phases) and fluxes (e.g. soil-atmospheric fluxes).
A multi-year NSERC-Industry research program has been underway at several waste rock piles in Northern Saskatchewan over the past 5 years. A key feature of this research program has been the development of practical means of measuring/monitoring some of the parameters outlined above. This presentation will briefly describe some of the techniques that have been developed or are currently under development through this research program. Some of the specific measurements and monitoring techniques to be discussed include the following: grain-size; soil suction and air pressure; water content and air-filled porosity; pore-fluid, pore-gas and solids chemistry; evaporative moisture fluxes and gas fluxes.
For each technique the method of measurement will be described, installation details will be outlined, and preliminary field data will be presented and discussed.