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
1999
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.
English
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
Environment Australia
Canberra (A.C.T.)
Supervising Scientist Report; 138
1 volume (various pagings) : illustrations, maps
application/pdf
642243417
Copyright
Environment Australia
https://www.legislation.gov.au/Details/C2019C00042
https://hdl.handle.net/10070/264982
https://hdl.handle.net/10070/462402
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
84 between the runs, 255 random selections were used subsequently for simplicity. The parameters varied for the Monte Carlo calculations were the dispersivity, aquifer porosity, Darcy velocity and retardation. The range used for each parameter is listed in table 6.3.2. Table 6.3.2 Parameter ranges used in the Monte Carlo analysis Parameter Range Longitudinal Dispersivity L 1 m to 10 m Transverse Dispersivity T 0.1 m to 1m Vertical Dispersivity V 0.01 to 0.1 m Darcy Velocity vD 5 x 10 -5 m/day to 5 x 10-6 m/day (East) 5 x 10-4 m/day to 5 x 10-5 m/day (West) Effective Porosity Pa 0.005 to 0.10 In the lower permeability aquifer to the east of Jabiluka, the concentrations of non-reactive solutes reduce to negligible levels 200 m from the mine. For example, the median sulphate concentration profile relative to the source concentration immediately downstream from the silos is given in figure 6.3.5. This solute profile was obtained for a 200 year run with a tailings permeability of 10-9m/s and an aquifer conductivity of 0.01 m/d. If the tailings concentration of sulphate, which is the most mobile of the solutes considered, is 20,000 mg/L (table 6.3.1), the three-dimensional solute transport model shows that the concentration reduces to 2000 mg/L immediately downstream of the silo (Kalf & Dudgeon 1999). The data in figure 6.3.5 show that the median sulphate concentration reduces to 20 mg/L at a distance 100 m downstream. Given the large additional dilutions through the surficial aquifer before the contaminant can reach Swift Creek, then additional dilution in the creek itself, Kalf and Dudgeon (1999) conclude that there is negligible potential for contamination of surface streams to the east. Figure 6.3.5 Variation of the median concentrations of SO4, U and Ra with distance east of the tailings silos at Jabiluka. Concentrations are expressed as ratios to the source concentration immediately downstream of the silos. The SO4 concentrations were calculated 200 years after placement. The U and Ra concentrations were calculated 1000 years after placement. Distance from Tailings Repository (m) 0 50 100 150 C on ce nt ra tio n R el at iv e to S ou rc e 0.0 0.2 0.4 0.6 0.8 1.0 SO4 200 years U 1000 years Ra 1000 years