Water drainage through waste dumps at Fording Coal Limited

CIM Bulletin, Vol. 75, No. 844, 1982

R.S. NICHOLS, Mine Engineer, Operations, and A.L. RUTLEDGE, Geotechnical Engineer, Fording Coal Limited, Elkford, B.C.

Waste dump development at the Fording River Operations in British Columbia began in 1971. In 1981, several unique as well as unplanned situations provided an opportunity to study water flows through waste dumps.The key to the drainage is naturally segregated rock sizes created by end dumping from the crest of a pile. The largest size material accumulates at the toe. Flow rates along the base of the studied dumps varied from 2,800 to 13,500 m3/day or 0.032 to 0.156 m3/s (1.2-5.5 cfs). Sediment concentrations in the water ranged from 1 to 1,800 mg/l.This paper describes water flows through dumps of varied lithology and maturity. The results suggest that neither long-term water flow nor contained sediments in small streams are jeopardized when crossed by end-dumped fills.

Keywords: Open-pit mining, Waste dumps, Waste materials, End dumping, Rock segregation, Water flow, Sediment concentrations, Drainage, Fording Coal.