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Uranium mining and monitoring at Kakadu

Estimates & Committees
Scott Ludlam 25 Feb 2011



Senator LUDLAM-Welcome back, Mr Hughes. I will just start with some follow-up on some issues that we spoke of last time you were here. In relation to the uranium mining operations in Kakadu, you told us that ERA was planning to install seven monitoring points and that the data would eventually be available to all stakeholders. You did not commit to a time line because I think the information you were giving us was fairly fresh. But ERA aimed to have that in place for the 2010-11 wet season. Can you just give us an update? The term you used was a vastly increased real-time monitoring network, which I was very glad to hear. What is the status of that at the moment and the public data reporting associated with that?

Mr Alan Hughes-ERA have indeed set up their monitoring network in Magela Creek. They have eight monitoring stations in or near Magela Creek now doing real-time EC monitoring. They also have stations in Gulungul Creek, which flanks the other side of the mine site. At this stage, they are reporting their results from those in response to incidents in an ad hoc fashion and in weekly water reports to all stakeholders.

Senator LUDLAM-Is it still grab sampling or is it real-time monitoring?

Mr Alan Hughes-No. It is real-time monitoring. But they still conduct their grab sampling program because that is part of their authorisation to do that.

Senator LUDLAM-So they are recording in real-time and they are reporting in weekly batches?

Mr Alan Hughes-Yes.

Senator LUDLAM-They are reporting to you, or is that material now live for the public?

Mr Alan Hughes-No. It is going to all the mine site technical meeting stakeholders.

Senator LUDLAM-Great.

Mr Alan Hughes-And the Gundjeihmi Aboriginal Corporation who also get copies of the data-the traditional owners.

Senator LUDLAM-That is good. How many new bores? Is it the seven in total that we spoke of last time?

Mr Alan Hughes-Sorry?

Senator LUDLAM-How many new water monitoring points?

Mr Alan Hughes-There are eight in Magela Creek and there are a number of other monitoring points scattered around operationally on the mine site. But ERA moved to answer specific questions on an operational basis.

Senator LUDLAM-Thank you. I forget exactly where we left this. You indicated some affinity for the idea that that data would eventually be reported publicly. Is there an update on that?

Mr Alan Hughes-I have spoken to ERA about the subject and they indicate their preparedness to ultimately do that when they get their systems sorted out. We have been through the same exercise ourselves and we know that it is best to make sure that the data is validated properly before it goes live.

Senator LUDLAM-But that is still the intention?

Mr Alan Hughes-That is still the intention.

Senator LUDLAM-Any estimated time of delivery?

Mr Alan Hughes-No.

Senator LUDLAM-Days, years, months?

Mr Alan Hughes-No. I suspect it is probably years at this stage. But the important thing is that ERA are providing the information in a timely fashion in response to any occurrences of interest to stakeholders.

Senator LUDLAM-What is the current situation up at Ranger following the heavy rains that were associated with cyclones Yasi and Carlos?

Mr Alan Hughes-The mine site has had a significantly above average wet season to date. They are currently sitting on something like 1,475 millimetres for the season, which compares to about 1,500 millimetres for the average whole of wet season. We still have some months to go and almost certainly they will exceed the average value of the season.

Senator LUDLAM-What is the current freeboard at the tailings storage facility there? How close is the facility to its maximum operating level?

Mr Alan Hughes-There is a target operating level for the wet season of 52.5 metres and a maximum operating level of 53.0 metres for the dry season. The tailings dam is currently at 52.16 metres. The catchment of the tailings dam is such that it receives only incident rainfall and there are no other significant inputs that occur. So it is millimetre for millimetre. Whatever rain falls is obviously what happens in the tailings dam.

Senator LUDLAM-It sounds like they are fairly close to their maximum permissible wet season level. What happens if the thing fills up?

Mr Alan Hughes-The maximum wet season level is a target operating level, but it does not pose any hazards to go beyond that to the maximum operating level for the dry season of 53 metres. For that to occur, the site would still need to receive 650 millimetres of rainfall. Typically, from this time of year to the end of the season, they will receive somewhere between 450 millimetres and 500 millimetres of rainfall.

Senator LUDLAM-That is operating very, very close to the margin.

Mr Alan Hughes-Yes.

Senator LUDLAM-What happens if the remainder of the wet season continues heavy?

Mr Alan Hughes-In the event that the water level in the tailings dam reaches the 53-metre maximum operating level, then a contingency plan kicks into place whereby water is transferred from the tailings dam to pit 3, the operating pit.

Senator LUDLAM-Did your office provide advice to either ERA or the NT regulator prior to ERA's suspension of processing operations at Ranger, which happened on 1 January-or the announcement, I should say? What was the nature of the advice? Were you involved in the decision to suspend processing operations there?

Mr Alan Hughes-We held general discussions with both the mining company and the regulator about the state of the situation. ERA voluntarily ceased processing operations to minimise the level of voluntary inputs into the tailings dam. So we did not ask them to do that, nor did the regulator.

Senator LUDLAM-You did not advise them one way or the other?

Mr Alan Hughes-We had general discussions about all sorts of options that might exist . ERA enumerated the plan that they had in place to do that work. One of the early parts of that contingency was to suspend its operations and bring forward its scheduled maintenance program.

Senator LUDLAM-That is underway at the moment. Does your office have to make any kind of provision for the restart of operations? Will you be involved when the thing gets back up and running again?

Mr Alan Hughes-It is simply an operational decision by ERA to do that.

Senator LUDLAM-They will start it up when they are ready?

Mr Alan Hughes-Yes.

Senator LUDLAM-What is the status of ERA's application for the proposed heat leach up there?

Mr Alan Hughes-The proposed heat leach is being assessed by the Northern Territory government under the bilateral arrangements between ourselves and them. ERA submitted a draft of the EIS to the approvals and wildlife division of our department and the Northern Territory government last Thursday. That draft is a document which allows the regulators to assess whether or not the guidelines have been met by the document. In the event that the regulators are happy that the document addresses all the guidelines, they will inform ERA and at that stage ERA will then be at liberty to release the EIS for public comment.

Senator LUDLAM-But I do not know that you will be able to tell us when that would be made public. Is that entirely up to the proponent when it is final?

Mr Alan Hughes-The Approvals and Wildlife Division may be able to provide you with some additional information on that particular aspect of the EPBC Act. It is not part of my brief to give that.

Senator LUDLAM-You are one of the inputs. Is anybody at the table able to tell us when the heat leach EIS might be made public?

Dr Grimes-We made a decision that we would have to call the relevant officer here to answer your question.

Senator LUDLAM-Yes, fine.

Dr Grimes-Peter Burnett is coming to the table to assist.

Senator LUDLAM-Welcome, Mr Burnett.

Mr Burnett-I only caught the second half of your question. Was it about the time line for the EIS on the Ranger heat leach assessments?

Senator LUDLAM-Yes-specifically when it might be made public.

Mr Burnett-Now that the draft has been lodged, we will assess it. If it is satisfactory to the minister's delegate, we will give the company approval to publish the EIS. The timing is then up to the company. They presumably will do that shortly after getting approval if they get approval. But if they wanted to take a bit longer about it, that would be at their discretion.

Senator LUDLAM-Yes. I am just trying to work out how the process works. Has there been any further movement on assessment or otherwise of the decline for proposed underground mining there? Are you involved in any way with that proposal?

Mr Burnett-Yes. That was the subject of a separate referral. This is the exploration decline you are talking about?

Senator LUDLAM-You are calling it an exploration decline, so we will stick with that language if you want.

Mr Burnett-The exploration decline was declared to be a not controlled action back on 17 May 2009.

Senator LUDLAM-So you have no involvement for the time being?

Mr Burnett-Not for the exploration decline.

Senator LUDLAM-Until it is referred. Mr Hughes, in response to a recent question on notice, you confirmed that seepage from the Ranger tailings facility is moving north. Can you provide any detail on the extent of this movement and your current thinking about management or intervention options? The company's long-term rehabilitation obligations are that the project area be reincorporated into Kakadu National Park and that it has to be rehabilitated back to a standard or an environment similar to the park. You have said before, and the company has insisted, that that contamination is not moving offsite from the lines that they have put on the map of the lease area. To what extent is the seepage moving north? What is the current state of thinking about how you would return that to the state that it was in before the mine was there?

Mr Alan Hughes-There are a whole bunch of additional monitoring bores intended to be drilled around the site which will provide us with a great deal more clarity on what the distribution of any seepage plumes are. However, early work in some bores to the north of the tailings dam which were probably within 200 or 300 metres of the dam have detected some seepage. There have been draw-down tests on that which showed that the rates of seepage at that point were quite low-of the order of half a cubic metre a day or something like that.

Senator LUDLAM-So at a distance of a couple of hundred metres. Have you been able to ascertain the water quality as well as the quantity that is moving?

Mr Alan Hughes-The water from those bores has been sampled and analysed and it is significantly diluted by the ground.

Senator LUDLAM-What is the furthest distance you would say you have detected seepage moving away from the tailings dam? How far can you detect the signature of the change in water quality?

Mr Alan Hughes-If indeed those bores are detecting seepage from the tailings dam, and it is thought that they are, they are probably approaching the limit.

Senator LUDLAM-Approaching what, sorry?

Mr Alan Hughes-Approaching the limit of the range that you would be able to detect it before the water got to a quality where it was relatively indistinguishable from other ground water.

Senator LUDLAM-Yes. I realise it is blending with water that is already there.

Mr Alan Hughes-Yes.

Senator LUDLAM-You said a couple of hundred metres. Can you be a bit more precise?

Mr Alan Hughes-No. I would like to see the results of the additional monitoring bores that are being put in and see how those settle down. It will be some time before we would really be in a position to say anything that was more precise than that.

Senator LUDLAM-Okay. While we have you on precision, why do you think it might be a couple of years before the real-time monitoring results are put into the public domain? I do not understand that at all.

Mr Alan Hughes-As I explained before, with our own experience on putting real-time monitoring results in the public domain, it takes us a good week to actually go through the data and verify the data, validate the data and then process the data to put it up on our website.

Senator LUDLAM-Okay. That is a couple of weeks. That is really different to a couple of years. A couple of weeks I think most people would probably accept.

Mr Alan Hughes-No. It takes a couple of weeks for us to validate the data.

Senator LUDLAM-Yes. why would that material not then immediately go into the public domain, once you have done that?

Mr Alan Hughes-Sorry, that does. I admit to having misled you there.

Senator LUDLAM-Perhaps. I might have to go back and check the transcript. I asked when the real-time monitoring might go public and I thought I heard you say that it would be perhaps a couple of years. But if you want to expunge that from the record, I would be happy for you to do so.

Mr Alan Hughes-No. I probably misinterpreted the question. I thought you meant by real-time monitoring in that case that it was actually live and ticking over so that you were watching what was happening in the stream. We take our real-time monitoring and we process the data and validate the data, and then we post it on the internet, usually within a week. 

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