Issued: 17 Oct 2019
The Department of Environment and Science (DES) approved Adani’s Groundwater Dependent Ecosystem Management Plan (GDEMP) today (13 June 2019).
Adani submitted its most recent version of the plan, addressing the department’s feedback, yesterday.
The GDEMP’s assessment has been rigorous and based on the best available science. DES and Adani have met regularly to ensure the plan is robust and provides the maximum environmental protection.
In assessing the plan, both Adani and DES took on board advice from CSIRO and Geoscience Australia – the same advice considered by the Commonwealth Government in approving an earlier version of the GDEMP in April this year.
DES sought further clarification and advice from CSIRO and Geoscience Australia, which it received on 7 June 2019.
Based on this advice, DES is satisfied that the GDEMP sufficiently establishes the main source aquifer of the springs as the Clematis Sandstone.
CSIRO and Geoscience Australia also confirmed that some level of uncertainty in geological and groundwater conceptual models always exists.
DES has required additional commitments from Adani to undertake further scientific work over the next two years. This is required to identify any potential contribution from other aquifers and strengthen the GDEMP.
Additional commitments in the approved GDEMP include:
- further work to improve the understanding of the source aquifers of springs in the locality, particularly the Doongmabulla Springs Complex, including:
- undertaking detailed hydrogeochemical analysis of groundwater and spring samples from different springs within each spring complex
- undertaking isotopic analysis (including noble, radioactive gases and strontium isotopes where isotopic analysis is not sufficient)
- examining core samples from new bores to attain a better understanding of hydraulic properties and provide detailed geological mapping
- incorporating air-borne electro-magnetic modelling undertaken by Geoscience Australia to improve hydrogeological understanding of the area
- using a bore in the Dunda Beds (also known as the Rewan Formation) as an early warning trigger for groundwater drawdown monitoring in the Carmichael River.
Additional measures in the GDEMP also address concerns raised last week by Flinders University scientists that the Permian aquifers should not be ruled out as a Doongmabulla Springs Complex source.
These include installing a new bore below the Rewan Formation, in the vicinity of the Doongmabulla Springs Complex, to assist in determining if the Permian aquifers (Colinlea) form a source for the springs.
Adani is also required to review hydrological, hydrochemistry analyses and seismic information as part of its second geological and groundwater remodelling after box cut mining starts, and review seismic information pertaining underground mining impacts (which is scheduled to start in year 10 of the project). Further seismic studies may also need to be undertaken.
Underground mining will not commence until these actions are completed and only if predicted impacts are consistent with approved impacts. Likewise, if the hydrogeological conceptualisation differs from that of the approved project, approval must be sought prior to relevant impact causing activities.
The GDEMP is the second of the two environmental management plans (the other being the Black-Throated Finch Management Plan, approved on 31 May) that needed to be approved before Adani could begin significant mining activities at its Carmichael mine site.
Both plans are a requirement of Adani’s EA.
For details of what constitutes “significant mining activities”, refer to Appendix 1—Definitions of the EA for the Carmichael mine, available at Environmental authority EPML01470513.