Rehabilitation of Uranium mines

Background

A variety of remotely sensed data have been acquired by SSD. Examples include: Compact Airborne Spectrographic Imager (CASI) (Nabarlek, Rum Jungle), DeBeers Hyperspectral Mapper (Ranger, Nabarlek and Rum Jungle) and temporal Quickbird data (Nabarlek). In addition, airborne gamma ray data has been acquired at varying line spacings (Nabarlek, upper South Alligator River valley, Sleisbeck). The overall aim is to assess the suitability of these data for minesite assessment, both for operational and rehabilitated mine surfaces.

Current research projects

Assess a variety of spatial, spectral and temporal scaled remotely sensed data for rehabilitation assessment

The remotely sensed data that has been acquired to date are being assessed for their cost/benefit and suitability of spectral, spatial and temporal characteristics on a site-by-site basis. Once existing data have been analysed, this project will use an analysed ground-based spectral library database

  • to make recommendations on suitable remotely-sensed data for minesite rehabilitation assessment
  • to acquire simultaneously a variety of spatial, spectral and costed datasets, as seen suitable by the ground-based database
  • to analyse and quantitatively compare such data and perform a cost-benefit analysis.

Project leader: Dr Kirrilly Pfitzner.

Development of a spectral library for minesite rehabilitation assessment

SSD aims to understand the spectral response of vegetation species which are important for mine site rehabilitation assessment, including introduced weeds and natives, in order to make recommendations on the most appropriate monitoring method. To achieve this, approximately monthly reflectance measurements of key species were sampled to establish a time series. The project aims are addressed by the following research questions: What are the fortnightly spectral responses of ground cover vegetative species? Can ground-cover vegetative species be distinguished using ground-based reflectance spectra, and if so, what spectral resolution is required? At what phenological stage is maximum separability detected and is there a phenological stage when species are confounding? What are the implications for hyperspectral imaging through-out the year? Data analysis is underway and the hypothesis is that with a well designed approach to collecting field spectral measurements and metadata, extraneous factors can be accounted for, accurate processing of spectra can be performed and the first database of Top End spectra relevant to the mine environment can be developed.

Project leader: Dr Kirrilly Pfitzner.

Some relevant publications

Pfitzner K., and Clifton, R. (2006) Integration of Airborne CASI and Gamma Ray data for mine site characterisation. Journal of Spatial Sciences, 51 (2) (December 2006).

Pfitzner K., Bollhöfer A., and Carr, G. (2006) A standard design for collecting vegetation reference spectra: Implementation and Implications for Data Sharing. Journal of Spatial Sciences, 51 (2) (December 2006).

Pfitzner K (2005) Mining and Exploration: Radiation Assessment, Position June/July 2005, 54-47.