Alligator Rivers Region Technical Committee

Meeting 37

29 - 30November 2016

Record of meeting
Darwin, NT

This document is a summary record of the scientific information presented to, and the discussion and actions arising from, the 37th meeting of the Alligator Rivers Region Technical Committee. ARRTC meeting summaries are used to inform planning and prioritisation of scientific research activities.

ARRTC
Dr Simon Barry / Chair, Independent Scientific Member
Mr Andrew Johnston / Independent Scientific Member
Prof Paul Boon / Independent Scientific Member
Dr Jenny Stauber / Independent Scientific Member
Prof David Mulligan / Independent Scientific Member
Dr Gavin Mudd / Environment NGO stakeholder member
Mr Adam Thompson / Northern Land Council (by phone)
Mr Matthew Whitfort / Supervising Scientist
Mr Tim Eckersley / Energy Resources of Australia Limited
Apologies
Ms Jane Coram / Independent Scientific Member
Mr Peter Waggitt / Department of Primary Industry and Resources
Mr Justin O’Brien / Gundjeihmi Aboriginal Corporation
Dr Kevin Frost / Uranium Equities Limited
Presenters and observers
Dr Geoff Pickup / Consultant
Ms Michelle (Shelly) Iles / Energy Resources of Australia Limited
Ms Sharon Paulka / Energy Resources of Australia Limited
Dr Ping Lu / Energy Resources of Australia Limited
Mr Gavin Otto / Department of Primary Industry and Resources
Mr Chris Malcolm / Gundjeihmi Aboriginal Corporation
Dr Howard Smith / Northern Land Council
Mr Keith Tayler / Supervising Scientist Branch
Dr Rick van Dam / Supervising Scientist Branch
Ms Berlinda Bowler / Supervising Scientist Branch, Secretariat
Ms Katrina Cox / Supervising Scientist Branch, Secretariat
Ms Kate Dixon / Supervising Scientist Branch, Secretariat
Mr Peter Baker / Supervising Scientist Branch (Presenter)
Dr Renee Bartolo / Supervising Scientist Branch (Presenter)
Dr Andrew Harford / Supervising Scientist Branch (Presenter)
Dr Che Doering / Supervising Scientist Branch (Presenter)
Dr Chris Humphries / Supervising Scientist Branch (Presenter)
Dr Tim Whiteside / Supervising Scientist Branch (Presenter)
Mr John Lowry / Supervising Scientist Branch
Dr Mike Saynor / Supervising Scientist Branch
Mr John Miller / Supervising Scientist Branch
Ms Fiona Evans / Supervising Scientist Branch
Mr Peter Medley / Supervising Scientist Branch
Dr Tom Mooney / Supervising Scientist Branch
Dr Melanie Trenfield / Supervising Scientist Branch
Mr Mike Welch / Supervising Scientist Branch

ACRONYMS

ARRTCAlligator Rivers Region Technical Committee, the Committee

ATRSupervising Scientist Annual Technical Report 2015-16

COPCContaminant/s of potential concerns

DPIRDepartment of Primary Industry and Resources, Northern Territory

DEWNRDepartment of Environment, Water and Natural Resources, South Australia

ERAEnergy Resources of Australia Limited

ERISSEnvironmental Research Institute of the Supervising Scientist

GAGeoscience Australia

GACGundjeihmi Aboriginal Corporation

KKNKey Knowledge Needs

NLCNorthern Land Council

OWSOffice of Water Science, Department of the Environment and Energy

RCMRanger Conceptual Model

SSBSupervising Scientist Branch, Department of the Environment and Energy

TSFTailings Storage Facility, Ranger uranium mine

1Welcome and opening session

The meeting commenced at 9.05 am.

The Chair, Dr Simon Barry, welcomed members and observers to the meeting.

1.1Acknowledgement of Country

The Chair acknowledged and paid respect to the Larrakia people, the traditional owners, past and present, onwhose country this meeting took place.

1.2Disclosure of conflicts of interests

Dr Mudd noted he continues to undertaking consultancy work for the GAC.

Dr Stauber noted CSIRO assisting with SSB’s uranium sediment toxicity project.

1.3Attendance, apologiesand 1.4 observers

As recorded above.

1.5Correspondence

ARRTC noted the status of correspondence (no incoming or outgoing) to 29 November 2016. The Chair advised his next letter to the Minister will consolidate both meetings 36 and 37.

1.6Governance

An update on the status of new governance arrangements was provided by SSB. SSB advised it does not expect any significant changes to the ARRTC’s functions as a result of the governance review, and would write to the Committee on governance arrangements following consideration of same by the Minister. Regarding concerns members raised at the ARRTC 36 regarding tenure duration, SSB confirmed those concerns were noted and given consideration.

1.7Publications

In addition to the ATR itself, publications for the Supervising Scientist for the period July 2015 to June 2016 are at Appendix 1 of the ATR.

2ARRTC 36 Outcomes

2.1ARRTC 36 – Summary record

ARRTC agreed to the new format, and the summary record of ARRTC36 was endorsed as provided, with minor edits.

2.2ARRTC 36 – Actions arising

Actions noted as complete were removed. Outstanding actions were updated.

3Research

3.1Energy Resources of Australia Limited –Mr Tim Eckersley and Ms Sharon Paulka, ERA

Associated presentation: 3.1 ERA Operations and closure update for ARRTC 37, November 2016

Associated paper:Report to the Alligator Rivers Region Technical Committee meeting # 37 Summary of recent environmental studies (ERA report ARRTC37.pdf)

Mr Eckersley provided an update on Ranger operations.

Health and safety:ERA reported itsbest safety performance on record with just one medical treatment case (September 2016) year to date. Health and safety initiatives remain focussed on delivering the Process Safety Improvement Plan and implementation of the Critical Risk Management Plan.

Environment performance: There were four incidents recorded since the last ARRTC meeting – all within containment/bund areas with no release to the environment.

Water management: Management of pond and process water is on track, and the brine concentrator is performing well.

The status of Ranger 3 Deeps was reported as remaining in care and maintenance.

ERA reported its business is tracking well and it has sufficient cash reserves to meet rehabilitation costs. Current workforce constitutes around 360 staff and 40 contractors.

Ms Paulka provided an update on Ranger closure activities.

An update was provided on the Ranger Groundwater Drilling Program. Additional groundwater bores were recently installed to look at potential groundwater seepage to the north, to the south and south west of the TSF, to the east looking at groundwater plumes from the processing area, and the diesel bund area.

The program is based on recommendations of the 2014/15 Ranger Annual Groundwater Reportand aims to enhance the groundwater network. Thirteen bores have been installed at 10 locations with some bores nested to cover multiple aquifers at some locations.

Closure is reported to be progressing and tracking to plan.

With respect to closure planning, ERAis reviewing and updating its closure plan. This will be provided to stakeholders for review and approval before the end of 2016. Closure planning activities for the last quarter 2016 include a scoping study for demolition, TSF deconstruction planning, and a scoping study for the closure Feasibility Study.

Closure execution: From the TSF, 2.7 Mm3 of tailings had been removed as at end October 2016, with approximately 20.2 Mm3 remaining. 71 ML of brine had been injected to the base of Pit 3 as at end October 2016, and the Pit 3 tailings beach continues to be maintained.

Closure milestones: Once approval is received, bulk backfill of Pit 1 will commence with completion due by2020. Pit 3 is receiving dredged tailings. The next milestones for Pit 3 are for the processing plant and dredged transfer of tailings to be completed, then installation of prefabricated vertical drains. Brinesfrom the brine concentrator injected into wells in the Pit 3 underfill is ongoing until 2025. A need for remediation and/or revegetation strategy for contaminated sites is being determined. The processing plant will continue operations until end 2020, before decommissioning of infrastructure can take place.

Surface water model: The existing model developed by the Australian Institute for Marine Science and the Water Resource Laboratory has been updatedby ERA to incorporate the new final landform (version 5). Predicted magnesium concentrations downstream of the confluence of Magela and Gulungul Creeks arelow (max 0.5 mg/L), and well below the current criterion.It was noted that in this instance,modelled concentrations do not take into account natural background.ERA is currently preparing a scope of work for a consultant to review and progress the surface water model. The next phase scope will include flow in Gulungul Creek and identifying and better understanding TSF input.

Ranger trial landform: ERA provided the ARRTC with images of the TLF taken in November 2016. Post-burn recovery of the treatment plot andprogress of seedling and tube-stock plot was noted.

Jabiluka revegetation: Images contrasting end 2013 with end 2016 were shown. Progress of the overstorywas noted, however it was also noted that the understory was slow to progress, with only some sedges and grasses barely visible.

ERA presented images of the final landform version 5, pointing out the historical (pre-existing) and to be created drainage lines, and including an overlay of the final landform with the original 1978 landform. The topography and slope analysis, including cross sections of the final landform, were shown.

The ARRTCwas interested in:

  • Being provided with a red/green/blue drape of final landform over an aerial photo.
  • The fate of the access road and RP1. ERA reported the road will remain indefinitely to enable ongoing access to the site, including for site management and monitoring, and the RP1 willremain in some form for a period of time yet to be determined.
  • What materialsunderpin the final landform design. ERA confirmed wasterock of various thicknesses from approximately 1-8 metres thick, with the thickest areas of wasterock over Pits 1 and 3.
  • Whether the scope of the next surface water model will include higher cross-channelresolution across Magela Creek. ERA advised this was not readily possible.

5.1Supervising Scientist, including supervision – Mr Keith Tayler, SSB

Mr Tayler provided an update on the Supervising Scientist Branch activities.

The Committee were advised that Dr Diana Wright, former Supervising Scientist and First Assistant Secretary of the Science Division, had recently retired, and Mr Matthew Whitfort will remain in the position of acting Supervising Scientist and First Assistant Secretaryuntil the position is permanently filled in 2017.

Mr Tayler noted the Branch’s structural changes were complete and new business processes in place, which has improved efficiency across a number of activities including reporting. One such efficiency has been the production of the ATR– which is now a standalone publication. Statutory reporting has been streamlined and incorporated into the Department’s Annual Report. Moving to the year ahead, the Branch has moved to an orderly annual operational plan which maps out governance and branch management activities for the forthcoming 12 months.

The Branch continues its close relationship with, and draws on expertise from, the Department’s Office of Water Science.

There remains a big focus on the rehabilitation of Ranger as the Branch awaits the closure plan from ERA. The Branch is in the process of developing a 5 – 10 year plan with ERA – expected to be complete by April 2017 – that arises directly from ERA’s closure plan and the KKNs.The Branch is committed to continue to monitor and address resourcing requirements now and into the future. The Branch is aiming to set up enduring relationships with key stakeholders and scientific bodies including, for example, CSIRO, the South Australian Government’s Mining and Petroleum Services Centre of Excellence (with capabilities in Leading practice in mine rehabilitation and environmental protection), and the Charles Darwin University, which it will draw upon for expertise as required, to progress the significant body of work expected over the next decade. It is expected that, by ARRTC 38 in May 2017, a clear five year work plan will be available which, if sufficient funding is available, willenable contract setting with partner organisations to be put in place. The ARRTC will be able to track and assess progress against the work plan. The Branch is also setting up a dedicated Department-based project on closure with reporting mechanisms that will enable the Minister and Departmental Executive to track progress.

The Branch is in the process of developing Rehabilitation Standards, to provide ministerial advicein accordance with theEnvironment Protection (Alligator Rivers Region) Act 1978. The Rehabilitation Standards are based on the culmination of 30 plus years of research by the Branch to date, and will quantify what will be required to meet the Environmental Requirements. The Rehabilitation Standardswill give good visibility of the science underpinning each given standard, and will provide a scientifically robust basis for decisions. The draft Standards will be circulated to relevant stakeholders (including the GAC) for comment before being finalised.

3.2ERISS 2015-16 and 2016-17 research and monitoring overview – Dr Rick van Dam

Associated presentation: 3.2 ERISS research program overview 2015-16.

Associated paper: Supervising Scientist Annual Technical Report 2016-16.

Dr van Dam provided an overview of the ERISS research program.

Overview of progress: A significant number of projects are now dedicated to Ranger rehabilitation,while many of those dedicated to operational issues also address rehabilitation knowledge needs.For the period July 2015-November 2017, 11 projects were completed, 24 are active, and six are yet to commence. Rehabilitation projects are largely dedicated to developing, demonstrating achievement of, and monitoring of, closure criteria. ARRTC was provided with a list of projects completed and ongoing and which KKN each of the projects corresponds to.

Key achievements: Achievements for the Branch include the screening-level ecological risk assessment for decommissioning and post-decommissioning, development of new KKNs, ERISS restructure, the development of Rehabilitation Standards, multiple lines of evidenced assessment for magnesium water quality limit, revision and release of Ranger Water Quality Objectives (noted at ARRTC36), the Ranger Groundwater Workshop (agenda item3.3.3 below) and 21 peer-reviewed publications.

Rehabilitation Standards: The Supervising Scientist’s Rehabilitation Standards are being developed in accordance with section 5c of the Environment Protection (Alligator Rivers Region) Act 1978. Those currently in draft are listed in the table below. These provide quantitative values, based on the best available science, against which the achievement of the rehabilitation objectives can be assessed. They may be updated as additional relevant knowledge becomes available.Standard parameters are based on the rehabilitation theme as follows:

List of SSB Rehabilitation Standards in draft
Theme / Parameters
Water and sediment / Magnesium
Uranium and manganese
Ammonia – toxicity
Other contaminants of potential concern
Turbidity / sedimentation
Sulfate (acid sulfate soils)
Nutrients
Landform / Landform stability and erosion
Flora and fauna / Flora
Fauna
Radiation / Dose to humans
Dose to wildlife
Soils / Contaminants of potential concern

The ARRTC:

  • Noted there is no Rehabilitation Standard dedicated to aquatic flora and fauna. Dr van Dam described how the water and sediment quality standards go to the protection aquatic biota, i.e. the chemical standards are based on biological effects.
  • Noted the single toxicant work seemed like a ‘bottom-up’ approach that looks singularly at contaminant/impacts, as opposed to a ‘top-down’ approach that would look at synergies across contaminants and keystone species. Dr van Dam noted this is a key knowledge need that will be investigated in the future.
  • Was interested to know if the Rehabilitation Standards would be relevant after closure and for how long. Dr van Dam noted that given the timeframes involved, it is difficult to speculate, and this would be a matter to assess into the future as environmental (including biological) monitoring continues and can be compared to modelled predictions, and how the site responds to revegetation.
  • Noted concerns regarding trajectories, namely with respect to revegetation. The Committee were advised by Mr Tayler that the Rehabilitation Standards will not be trajectories as such, but rather ERA’s closure criteria constitute trajectories and how they can be achieved. Further information regarding revegetation trajectories, including taking into account threatening processes, being developed by ERISS will be presented at agenda item 3.3.5.
  • Noted concerns regarding long-term monitoring and at what point ERA may be relieved from its obligations. It was noted this will be a matter for decision makers, on advice from the Supervising Scientist.

ARRTC feedback process: Dr van Dam thanked the Committee for their feedback on the ATR. ARRTC agreed the process was more effective and efficient, and provided a good mechanism to record useful information and responses from ERISS on particular points. SSB will look at providing ARRTC with more time to consider meeting papers (including the ATR) into the future. It was agreed that it would be of value to include ERA into the review process; ERA advised it followed the same process for the previous meeting but for this meeting the process was not applicable. ERA agreed that a combined response from both SSB and ERA on questions raised by ARRTC concerning research projects underway would be of value.

The ARRTCcommended the SSB on the Annual Technical Report.

Looking forward: ERISS will have a 5 plus year KKN based research plan by May 2017.

SSB noted its recent attendance at a number of prominent international conferences, where it had received much interest and very positive feedback. ARRTC noted its support for the SSB in benchmarking against internationalpractices.

3.3Specific presentations

3.3.1 Over-arching

Ranger rehabilitation ecological risk assessment: list of low and moderate risks – DrRenee Bartolo

No presentation. Associated paper: 3.3.1 Ranger rehabilitation ecological risk assessment

At ARRTC’s request, SSB prepared and presented a summary of consolidated low and moderate risks from the overarchingrehabilitation and closure ecological risk assessment, for the decommissioning and post-decommissioning phases. Each of the risks comprise three components: the hazard, the pathway, and the endpoint/receptor; and are effectively sub-risks to the previously assessed high and critical ranked risks. The Committee was asked to keep this in mind when considering the summary.

SSB advised it will formally reconsider the risk assessment in a further ~ three years’ time. In the meantime, SSB will undertake a cross-check of the low and moderate risks with the high and critical risks to assess to what extent the low and moderate risks are captured by higher ranked risks, and note this on the summary, as well as the corresponding KKN. The summary will then be provided to ARRTC for comment, out of session.