Report

Curragh Coal Mine rehabilitation monitoring 2002 assessment

Grigg, A; McCallum, N J

2003

51

Centre for Mined Land Rehabilitation, The University of Queensland

Brisbane

QLD

11/11/03

monitoring; mine rehabilitation; revegetation; Curragh minesoil; Bowen Basin; Queensland

Report Type: Final report to Curragh Queensland Mining Limited includes CD in folder

Rehabilitation strategies at the Curragh coal mine entail reshaping of spoil piles to design slopes and the replacement of stockpiled topsoil, typically in strips along the contour alternating with strips of bare spoil of similar width. Tree and shrub species are sown into the bare spoil strips, an approach aimed at improving their establishment success by reducing competition from grasses. The topsoil strips are sown with a mix of improved pasture grass and legume species, with the expectation that ground cover will colonise the bare spoil strips with time to create a wooded bushland community. The proposed end-use for these areas is 'bushland', with commitments to achieve 80% cover and a minimum density of trees of 40 stems/ha. Currently, 2-3 separate areas of the mine, totalling around 60 ha, are rehabilitated each year. The Centre for Mined Land Rehabilitation was approached by Curragh mine to devise and conduct a program of assessment of minesite rehabilitation efforts. The broad aims were to provide information on the performance of rehabilitation as feedback to assess and improve the success and cost-effectiveness of on-the-ground practices, and as a basis from which to develop site-specific success criteria for sign-off purposes. The program is to cover an initial five year period (2002-2006).A plan of the program and explanatory notes are provided. The program was devised to monitor a maximum number of rehabilitation areas established in different years, and revisit these sites systematically into the future, within tight budgetary constraints. In the first two years of the program, rehabilitation areas established in six consecutive years from 1996 to 2001 will have been assessed, providing replicate data on three different rehabilitation ages since establishment (approximately 1,3 and 6 years old). This forms a solid basis for following trends in rehabilitation development over time.