Book Description
Rock drains are zones of coarse rockfill capable of transmitting normal streamflows which are commonly constructed in mountain valleys for conveying streams along the bottom of waste rock dumps at mines. This report describes research conducted to evaluate issues related to the long-term performance of rock drains in the mining industry. Field research and monitoring was conducted at the Manalta Coal Line Creek Mine in British Columbia, where the mine's main rock drain began construction in 1989. Baseline data were also collected prior to construction. Other research activities included examination of waste rock properties, streamflow monitoring, flow-through tracer tests, sampling of suspended solids and bed load, rock drain flow-through modelling, water temperature and chemistry monitoring, and sampling of aquatic invertebrates. The report findings are presented for three main areas of study: physical characteristics of rock drains, including drain design and construction, waste rock properties, and geophysical investigation of rock dumps; flow-through characteristics, drain hydrology, water levels, and model results; and environmental effects of rock drains on water temperature, water chemistry, and aquatic invertebrates.