• Change text size
• Skip to content

Supervising Scientist Division

Search:

• About us
• Contact us

• Home
  • Atmosphere
  • Biodiversity
  • Coasts and marine
  • Heritage
  • Human settlements
  • Land
  • Living sustainably
  • Parks and reserves
  • Water
  • EPBC Act

• Supervising Scientist
  • About us
    • Alligator Rivers Region
    • Legislation
    • Structure of SSD
    • Services
    • Working at SSD
  • Environmental monitoring
    • Ranger - Magela chemical data
    • Ranger - Gulungul chemical data
    • Jabiluka - Ngarradj (Swift Creek) chemical data
    • Ranger - Magela biological data
    • Radon monitoring stations
    • Surface Water Chemistry Monitoring
    • Sampling maps
  • Environmental research
  • Supervision and assessment
    • Working with the Northern Territory Government
    • Environmental incidents
    • Uranium mining in the ARR
  • Keeping the community informed
    • Committees and associations
    • Consultation with indigenous communities
    • Displays
  • Publications

Download

• The chemical composition and extraction behaviour of Ranger RP1 sediments (PDF 563 KB)

About the report

Ranger Retention Pond 1 (RP1) was excavated as part of mine construction in 1980. Its primary purpose is as a sediment trap, to prevent erosion products from mine rock used in tailings dam construction, and other purposes, leading to unacceptable increases in the suspended load of Coonjimba Creek, and ultimately Magela Creek.

There have been recent observations of increased uranium concentration in RP1 water, and the discovery of elevated uranium concentration in RP1 sediments. These are presumed to primarily constitute alluvium transported from the catchment. Hence the chemical contents of the sediments, at least to 10cm depth, are probably mostly catchment derived, and only weakly related to chemical processes in the pond itself. An exception to this is the formation of sulfidic mineralisation, which is probably caused by in-situ reduction of sulphate by sulphate-reducing bacteria.