Assessment of the Jabiluka Project : report of the Supervising Scientist to the World Heritage Committee
Johnston, A.; Prendergast, J. B.; Bridgewater, Peter
E-Publications; E-Books; PublicationNT; Supervising Scientist Report; 138
Alligator Rivers Region
Main report--Appendix 2 of the Main Report. Submission to the Mission of the World Heritage Committee by some Australian Scientists ... --Attachment A. Johnston A. and Needham S. 1999. Protection of the environment near the Ranger uranium mine--Attachment B. Bureau of Meteorology 1999. Hydrometeorological analysis relevant to Jabiluka--Attachment C. Jones, R.N., Hennessy, K.J. and Abbs, D.J. 1999. Climate change analysis relevant to Jabiluka--Attachment D. Chiew, F and Wang, Q.J. 1999. Hydrological anaysis relevant to surface water storage at Jabiluka--Attachment E. Kalf, F. and Dudgeon, C. 1999. Analysis of long term groundwater dispersal of contaminants from proposed Jabiluka mine tailings repositories--Appendix 2 of Attachment E. Simulation of leaching on non-reactive and radionuclide contaminants from proposed Jabiluka silo banks.
Uranium mill tailings - Environmental aspects - Northern Territory - Alligator Rivers Region; Environmental impact analysis - Northern Territory - Jabiluka; Uranium mines and mining - Environmental aspects - Northern Territory - Jabiluka; Jabiluka - Environmental aspects
Supervising Scientist Report; 138
1 volume (various pagings) : illustrations, maps
https://hdl.handle.net/10070/462403; https://hdl.handle.net/10070/462400; https://hdl.handle.net/10070/462405; https://hdl.handle.net/10070/462406; https://hdl.handle.net/10070/462408; https://hdl.handle.net/10070/462409; https://hdl.handle.net/10070/462411
92 out pits at Ranger along with the tailings produced from the milling of Ranger ore. Following completion of mining, the pits would be covered with inert waste rock and revegetated. All waste rock produced at Jabiluka would be used as cemented backfill in the mine void. In addition, some of the waste rock and low grade ore at Ranger would be transported to the Jabiluka site and used as cemented backfill in the mine void. The only surface facilities at Jabiluka would be an ore stockpile, a waste rock stockpile and a water retention pond to collect and store all rainfall runoff from the stockpiles and water pumped from the mine. No water would be discharged from the mine. Following completion of mining, the pond would evaporate to dryness over several years and the site would be rehabilitated. Under the JMA option, which is the subject of this review, a mill would be constructed at Jabiluka to process the ore. All tailings would be dewatered to form a paste to which would be added concrete and the concrete paste would be returned underground to the mine void and to silos excavated underground, probably in the sandstone to the east of the orebody. The excavated sandstone would be placed in stockpiles on the surface at Jabiluka. All water pumped from the mine and rainfall runoff from the mill and ore stockpile would be collected and stored in a water retention pond. Rainfall runoff from the sandstone stockpiles would freely discharge to Swift Creek but ERA would, as specified by the Minister for the Environment, be required to take whatever steps are necessary to ensure that suspended solids concentrations in Swift Creek do not rise significantly above natural values. Because the JMA option requires the construction of a mill at Jabiluka and requires additional waste rock stockpiles, the RMA option is preferred both by ERA and the Government. However, the RMA option requires the specific approval of the traditional owners and this approval has not been given. It is for this reason that ERA proposed the JMA option. The Mission report was critical of ERA for proposing to proceed with the JMA option despite not being the preferred environmental option. This review, however, and the original assessment of the JMA proposal by Environment Australia have shown that, while the RMA option is preferred, the risk to the environment arising from the JMA option is minimal and, in particular, that the wetlands of Kakadu National Park will not be threatened if the project proceeds. 7.3 Location and extent of the Jabiluka ore body The extent of the No 2 orebody at Jabiluka has not been fully delineated at depth in that section of the orebody to the east of the Hegge fault (see for example fig 6.4 of the EIS). It is the intention of ERA to carry out further drilling once the decline reaches the orebody in an attempt to establish whether or not further reserves of uranium exist. The possibility of finding further uranium ore at depth was assessed in the Environment Assessment report on ERAs proposal at the EIS stage. The primary issue considered was the capacity of the two pits at Ranger for the disposal of tailings from both the Ranger deposits and tailings from Jabiluka. The Government decided that, when placed in the pits at Ranger, tailings from the combined operations at Ranger and Jabiluka should not exceed specified depths below the ground surface. The effect of this decision is to restrict mining at Jabiluka to the currently delineated orebody. Any proposal to mine more uranium than would satisfy this requirement will require further assessment under the Environment Protection (Impact of Proposals) Act 1974. Hence, if the Ranger Mill Alternative were to proceed, the mining at Jabiluka would be restricted to the currently delineated orebody and the period of mining would be about 30 years.