Revegetation at the Sullivan Mine – research to closure – a case study

The Sullivan orebody was a world class iron-lead-zinc sulphide deposit that was discovered in 1892 near what became Kimberley, BC. The Sullivan Mine operated from 1910 to 2001. A research programme to investigate the conversion of waste rock dumps and tailing ponds into productive forest and rangeland was initiated in 1972. Initial studies focussed on revegetation treatments for waste rock and mill tailings. Studies demonstrated that complex covers with at least 30 cm of growth medium is required to grow a satisfactory grass dominated plant community and at least 60 cm is required where alfalfa is a desired component. The studies also indicated that a float rock capillary barrier in the complex cover reduced the movement of acids, salts and metals into the growth medium. The reclamation plan prescribed the installation of native tree and shrub islands and corridors, extensive revegetation with agronomic grass and legume species and inclusions of small islands of native grasses. Native tree and shrub screening trials were used to determine which species would have adequate survival rates to contribute to the development of the wildlife habitat end use objectives. Treatments that created conditions that were free from competitive vegetation were tested to improve the probability of tree and shrub planting success. Revegetation strategies that include the incorporation of native grass and legume islands need to consider the invasive nature of agronomic species with appropriately sized (large) islands. In addition, native tree and shrub islands and corridors need to be large enough to create unique and purposeful wildlife habitats. The long term succession in agronomic plant communities will be assessed through a rationalised monitoring programme. In the future, the plan is to incorporate the investigation of other ecological parameters including soil development, root development, soil flora and fauna, and use patterns by a range of wildlife species.