Territory Stories

Assessment of the Jabiluka Project : report of the Supervising Scientist to the World Heritage Committee

Details:

Title

Assessment of the Jabiluka Project : report of the Supervising Scientist to the World Heritage Committee

Creator

Johnston, A.; Prendergast, J. B.; Bridgewater, Peter

Collection

E-Publications; E-Books; PublicationNT; Supervising Scientist Report; 138

Date

1999

Location

Alligator Rivers Region

Table of contents

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.

Language

English

Subject

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

Publisher name

Environment Australia

Place of publication

Canberra (A.C.T.)

Series

Supervising Scientist Report; 138

Format

1 volume (various pagings) : illustrations, maps

File type

application/pdf

ISBN

642243417

Use

Copyright

Copyright owner

Environment Australia

License

https://www.legislation.gov.au/Details/C2019C00042

Parent handle

https://hdl.handle.net/10070/264982

Citation address

https://hdl.handle.net/10070/462402

Related items

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

Page content

49 pond capacity would not be exceeded in that run. The largest of these 50,000 values is, therefore, the estimate of the storage capacity with a 0.00002 (1:50,000) probability of being exceeded during the 30-year mine life. The tenth largest of these values is the estimate of the storage capacity with a 0.0002 (or 0.02%) probability being exceeded in the 30-year mine life, and so on. Figure 5.2.1 Estimates of storage capacity required as a function of exceedence probability over the 30-year mine life under current climatic conditions Figure 5.2.1 shows the estimates of storage capacity required as a function of exceedence probability over the life of the mine. The volume of pond proposed by ERA in the PER was 810,000 m3. (This is based upon a 9 ha pond of depth 9.5 m (PER p 452) of which 0.5 m is freeboard required to take into account wave action and is therefore not available for storage except under emergency conditions.) The data in figure 5.2.1 indicate that the probability of this storage capacity being exceeded in the life of the mine would be about 1:1,000. Based on these simulations, the estimate of storage capacity required to achieve an exceedence probability of 0.01% (1 in 10,000) over the 30-year mine life is 940,000 m3 (an equivalent depth of 10.4 m in the 90,000 m2 storage area). Comparison of model with that used by ERA There are several differences between the approach adopted in this review by Chiew and Wang (1999) and the approach used by ERA to estimate the required storage capacity (described in Appendix B1 in the Jabiluka PER Appendices). In the ERA approach, 10,000 years of annual rainfall data were generated using a log-normal distribution. A 15-year water balance simulation was carried out using a typical 15-year sequence to provide a base data set. Ten simulations were carried out with the first year of the base data replaced with the wettest of the 10,000 years of the generated rainfall, with the first two years of the base data replaced with the wettest two-year sequence, with the first 200000 400000 600000 800000 1000000 0.00001 0.00010 0.00100 0.01000 0.10000 E st im at ed s to ra ge c ap ac it y (m 3 ) Probability of overtopping in the 30-year mine life 1000000 800000 600000 400000 200000 0