 Hi, mae'n Sam Illumweff, a rhai'r ysgolwyddon yn Llywodraeth Cymunicatio, yma ar Ysgrifod Dwylo Weston Australia. Mae'r UWA i'r cydnod yn fwyaf i'r eich sefyllfa yng Nghymru, oeddai'r cydnod Cymru, i'r cyfnod Cymru. Mae'r cydnod, roeddwn i'n gweithio'r ysgolwyddon yng nghymru. Dr Talitha Santini yw ysgolwyddon yn Llywodraeth Cymunicatio ar y Llywodraeth Cymru, o'r ysgol ffrigol ac yn ystyried oedd yn ysgol yng ngyfrineid yn Oest. Mae'r cyfrifiadau yn seradol a'r ysgrifennid yn eisteddf wedi'i gwirioneddol, gyfnodol, microbiologi a cyfnodol. Roedd y gallu gwirionedd ysgrifennid yn ystyried o'r ddechrau ymlaen i'r ffaith yn bwysigol yma, ryw o tinto, felol 32, Nwmant, Anglwgold, Ashanti, Alcoa, a Llywodraeth Llywodraeth, dylyried bydd argyrchu bod osweithlwlad i'ch gwbl yn ôl. Dwi'n arreïwisol atigol will-wasgwyr a dd humanitarian Cymru, fod yn gyfaf am erbyn. Adon ni'n mewn cyddarlun brydio ar Y UA, dweud yn ddim yn canedig hefyd i bwyf meddwl o bobl dros y gyfysgol a ddych chi'n clwydoeddio'r yr hun i gyflwyno'r kweinslwn ddigwydd yn y gwirion ei gweithio dros yma ac yn ymgylch yn ymddi a'r Y UA. Fyd ddim yn wneud Telythau ar Twitter at Talitha underscores Santini, ac dyna ni dyna ei chael hynny'n gwynhau mewn dysgu'r sglau'r ffeirydd o'r mukhaeieidau. Talitha efallai doedd chi ddod ychydig ychydig ychydig a'r cyfraeg sy'n cael... Dwi'n ceisio'r ffeirydd. Felly, os yw'r yma ond dyna. Mae gyfrifio dech demonstration â'r phod iod arna. Dwi'n cael ei gyrwch ffyrdd o'r hynllaeth Talitha i'w cael y gall. Ddod yn hynny'n i'w ddweudd yn ystadaf hwnnot a'i ddechrau. This is a photo from a lithium mine site in WA south west. We took a class that I teach in third year land rehabilitation. So some environmental science students down here is part of a week long field course last year. And for them and probably for a lot of you today, it was their first time that they'd gotten to see a mine site. Obviously with the restrictions at the moment we can't go there right now, and see it firsthand. Ond yna'r gwybodaeth y gallwn sydd wedi'i gwneud ei ysgol yw ymddangos o'r ffordd o'r hyffordd. Dwi'n gwybod i'r ffordd, ond y gallwn gweld y ffordd o gweithio a ffwrdd yn siaradidd. Dwi'n gweithio i'r hyffordd allan o'r hyffordd ac oedd i'r ffordd i'r ffordd i'r gweithio ar gyfer ymgyrch. Yn gweithio i'r busraedd yn ei ffordd i'r ffordd i'r busraedd i gyd ac oedd yn ei gwyrddio'r ffordd o'r bydd. a ddim yn ymgyrch yn ymgyrch yn ymgyrch ar y dyfodol o'r teimlo gwybod nhw. Roeddwn i'n gwybod bod yw'r cyflwyno gyda'r hynny o'r amgylcheddau o ffordd o'r gwahanol i'r cyflwyno a'r gwahanol i'r mynd i'w gwybod o'r mynd i'w gwybod i'r bywyd. Mae'n gwybod yn ymgyrch gwaith yw'r rhagwyr i'r awdurdod yma o'r cyflwyno. Yn ymgyrch, mae'n gweithio i'r cyflwyno i'r bywyd o'r mynd i'w gwybod, gan ystafael, y gweithio ar y dyfodol y gallwn gweithio dynol ac yn ddechrau ar y ddefnyddio. Yn y ffordd o'r ffodol rhan o'r fforddau yma yn Lleon Llywodraeth, yn Lleon Morgyn, ac mae'n rhan o'r gweithio'r gweld sydd y gael a'r apod ar y cyfnodau sydd yn rhan o'r mynd yn Australia a'r gloddau. Ond rydyn ni'n golygu ym mwy oherwydd yna'r gweithio'r gweithio'r gweithiau a'r angen o'r cyfnodd cyfnodd cyfnodd yn ymwneud o'r pethau newydd. Mae'r angen yn ymwneud yn y 1800 i'r angen, ac yn ymwneud, ymwneud ymwneud yn ymwneud, at y time yn ymwneud yn ymwneud. Ymwneud yw'r angen, rwy'n meddwl i'r angen. Ond, ymwneud o'r materiol ymwneud, ymwneud, ymwneud, ymwneud, ymwneud, ac ymwneud ymwneud o'r trwymyn sy'n cyfnodd, ymwneud, ymwneud yn ymwneud yn ymwneud, ein mod i'r angen ymwneud. Rwy'n meddwl ei eistedd yn gystiative, rwy'n meddwl i'r angen, ymwneud a'u sgwpach, ac yn dymi arweinydd a ffarras y cantgen ac rwy'n meddwl i'r angen. Draw ni wedi'n gweithio ddechrau o'r wych yn ymddangos a'r angen. Felly fynd i'r ansigol i'r angen o ffarras o frywur ar gyfer 0.3% o'r amgylchio'r syniad ar y modeliaf. Mae llunio'r angen yn 400,000 pln. Mae gennym ymddechrau o badaith gweithio'r streff. Mae gennym o bwysig iawn o'r cyflomintau miliwyrau a chyflomintau o'r llwyffydd honno o bwysig iawn o'r rhai gynhyrchu o fe wnaeth bod chi'n rhaid o'r ffotograff. Felly mae'n bwysig iawn o'r rhaglawn, mae'n bwysig iawn o bwysig iawn o bwysig iawn o'r rhaglawn. A dyma rai'r eich rhaid ei wneud i wneud o'r gronddau yn ymddechrau a'r wrthgrif. That's what's stopping the way, so that is the purity of these differentause that we're extracting. Continue to decrease over time. As humans tend to do we've gone for the easy high value staff first. And a lot of the resources that are left now are much lower concentration, then some of those materials that we were able to extract from in the past. And so necessarily that generates more waste than byproducts in the course of mining and refining. Why is this important? Well, this is particularly important ar y bwysig hwnnw o'r ei wneud iawn o'r economa ar ymwneud. Fe'i dweud hon, fe wnaeth arglwyddon eich drafodaeth yn uddiad o'r wneud omflaen gael eu twyd o amsiannidol a'r gyflaen ymlaen nhw. Felly yma mae'r ymlaen yefydig ar gwaith sydd os ymlaen nhw o'r wneud i agran ymlaen nhw ar ymlaen nhw. Dyma dros agran ymlaen nhw oedd eich mas o'r wneud ymlaener nhw o'r mae'r bwysig hefyd o'i Mae'r gweithio'r gweithio ar 10% gyda'r ffordd sydd gennym i'r product oed yn 50% o'r gweithio'r gweithio'r gweithio'r gweithio. Ond mae'n meddwl i'r gweithio ar Westin Australia. A chyflwch yn Westin Australia gweithio ar ar 30% o'r gweithio'r gweithio ar 19% o'r gweithio'r gweithio ar gweithio'r gweithio. Ieithi, fyddwn i'n meddwl i'r WA oedd ychydig rwy'n meddwl i'r gweithio'r gweithio'r Gweithio'r gweithio ar y sted. Maenwn i'r rhithbeth ar gyfer cyd-fisiwdd i'r cyffredin, yr adegwydol ydym yn diogel i'roses cyfleoedd yn hwnnw. Yn y troch bethwysau ar gweithio'r netteidiu mwy o ffordd ac mae'n rheswer y byddwysau o'r rhithbeth. Mae'r rheswer y Gymraeg areun o'r ddiforfer gan rhai ddechrau allan i fynd i'r rhithbeth, a'r rhithbeth o'r ddweud i'r rhithbeth oedd yn gweld o'r ganddaiddau ac mae'r rhithbeth ar gweithio o'r merchu iawn. Ond mae'n gwlawn llawer o iechyd o'roodledig mewn hyd have â'r cyffredinion i'w cyfyrddion rydych chi i'w hyd yw cyfyrddion, ac mae'n credu rhai ymdrygiad sefydliad o'r diagram sydd ond rwy'n mynd i'w rhai o fynd o'r cyffredinion o'r myndi, i gael â'r gen이�d maen nhw, roedd yr sriff yn gymuned ac yn cael rhai. A phrygau bastân o brinio'r hoffach, mewn ychydig hwnna ddyn nhw meddwl a yn ymgol, is that we're incredibly familiar with, essentially digging a large open hole in the ground to get down to whichever resource we want to extract. Sometimes we use underground workings either when we've gotten to a point in the open cup kit where we want to extract a deeper part of the resource or just straight down from the surface in some cases. Regardless of the mode of extraction, we usually get this rock and start hauling it out of that mine pit. This is where y troi'r sprwp ydyn nhw'n achosi'r bod hynny'n gweithio a bod sprwp'r ac yn ein bod yn gwahanol er oed. Rwy'n fawr go o adrodd y beselyn ystryg o'i oesodol Cymru, ac mae'n gwybod arbennig f인지ol yn cael cael amserol. Rydyn ni'n ganwyd o'i adder iawn y dyfyrdd. Mae'n rai'r adredge, rydyn traedd y leia sydd yn rhaid, a tu mfynwyr teiriw. A'r ddwyno iawn cyffredeg o'r rheswr i'n rhaid i'r bod yn bobl. The top soil in the way and we usually store it because we want to use that later for rehabilitation during my enclosure. The waste rock on the other hand is basically the material that we've extracted that's too low in concentration for us to bother processing it further. It's just not economically viable to do so. Some photos of what this looks like. This is a coal mine site in the UK and so you can see here what an open cup kit can look like. A larger zoomed out image at the top and you can see this top soil layer that nice rhan i'r adnod o'r materrwyr ar y cyfnod, sy'n rhan i'r adnod o'r baris ar y cyfnod. Yn y ddweud bod yn siŵr i'n ddweud o'r cyfnod ymlaen o'r ymlaen, yn y cerddau yma o'r ffordd, ddim o'r gwaith, sy'n sgwrs. Yn y ddiwedd i'r ddweud, oeddwn yn dweud yn gwirionedd iawn y rawr o'r materrwyr yn cyfnod i'r awr, a chyddiwch wedi'u cyfnod i'r argyrchu ymdill yn ei wneud. Fy hofnwys hynny, mae'n cymryd yn gwybod i ddefnyddio'r ymdill yn ymddill, a'r ffordd i ddechrau, ddyn nhw'n gyfle, oherwydd yr adeil yn y byw, ac yn cymryd yn mynd i ddefnyddio'r ymdill, a'i cymryd i'r beth oedd, a'n gwybod i'r adeil yn ei ddefnyddio'r ymdill, a'n gwybod i'r adeil yn ei ddechrau, ac sydd yn gwybod i'r ddechrau, ac sydd yn cael ei ddefnyddio'r adeil yn ei ddefnyddio'r adeil. i'r ddechrau i wneud i ddweud o edrych i ffrago ychydig. Rwy'n meddwl i ddweud bod yn dweud gan ychydig, felly ei ddweud eu cyffredinol o ran i'r hollwch ac i ddweud panfru o ddweud, rydyn ni'n meddwl oedd ymddangos i'r bobl. Rydyn ni'n meddwl i ddweud – yn cyfrifio, ond o'r lle, rydyn ni'n meddwl i ddweud rydyn ni'n meddwl i ddweud. Rydyn ni'n meddwl i ddweud i ddweud, rydyn ni'n meddwl i ddweud, ac na dydw i'r cyfaint gweithio. These we refer to as tailings. These were all the leftovers that were present in the ore that we brought up from the pit. That once we put through the new processing, we didn't want to have going into our product out to the market. So four kinds of mine waste and by-products that we produce. Each of these have different, just a couple of photos here, what some of the tailings storage can look like so again covering big areas of land surface and obviously posing a pretty interesting challenge when it comes time to finish mining return that area to a new end land use. So each of these materials comes with slightly different properties and don't worry too much about the detail here but this is just to show that a lot of these are at streams of pH so either very acid or very alkaline they can often be salty and they often don't have a lot of organic carbon content often they can be quite high in available metals as well and all of these are real challenges when it comes time as I just mentioned to remediate and close our sites. I'm going to walk through a couple of photos just quickly of some areas around the Mount Morgan mine site and then I'm going to loop back to what we do about these tailings materials in particular. I'm going to focus in on tailings because we produce about seven billion tonnes of tailings globally each year. You can see an example of some of these down the bottom here and they pose a massive challenge for closure when it comes time to finish mining and refining operations. As I've said regardless of the resource that they're extracted from they share some common properties so we see extremes of pH, high salinity, not much soil structure, no organic metal or nutrients and they either have a very fine or a very coarse particle size so really not like natural soils that you'd see for example in your backyard at all and part of our challenge is to figure out how do we transform these materials so that they do become functional soils. A couple of aerial photos of the Mount Morgan mine site that we saw that photo of at the beginning of the talk and I wanted to show this view to give you an idea of the spatial area that these kinds of facilities can occupy so you can see the scale bar down here at the bottom. This is an area of about two by three kilometres that occupies and this area here is the open cut pit where the copper and gold ore was extracted that now has filled up with water through rainfall over time. Down here you can see some of the waste rock storage areas, some of the tailings storage areas are up here and some more waste rock and tailings storage areas over there as well as the refinery site in the middle and so given that this site was operating for about a hundred years it's pretty interesting to see that so little rehabilitation has been done so this is a view out into that open cut pit. It holds about 12,000 mega litres of water sitting at a pH of three and that might not mean much to most people but that's basically sitting there at the pH of lemon juice so if you can imagine any animals or wildlife trying to access that water if you can imagine that water escaping out into the deep river nearby you can understand that that would cause some pretty significant impact. It's so acidic because of the oxidation of pyrite so in this ore in this area around the mine site the copper ore co-ocurred with this mineral that we call pyrite or iron sulfide and when that's exposed to oxygen as you can imagine is hanging around the atmosphere there and with some rainfall to supply the water you get rapid oxidation of that pyrite and it generates sulfuric acid and that is the process that has acidified this huge body of water here and is posing a really big challenge for remediation and closure. One of the strategies that's been tested is to use these evaporators so essentially sucking up the acid mine drainage and spraying it back over the site to try and reduce the volume of water that's sitting there another is injecting lime into the water to help neutralise the pH. About 40 million dollars has been spent on rehabilitation so far and it definitely still got a long long way to go in terms of treating the sheer volume of water that's sitting here so this highlights one of the great challenges and that we need to come up with low cost fast ways to remediate these materials. Some more views across the site here so you can see really clear erosion in the background from slopes that are quite steep that haven't had much vegetation establishment and that continue to feed new material into that pit. You can see some of the piles of slag from the copper smelter here as well and here you can see some of the tailings that's being stored on the other side of this wall seeping out and into one of the other water storage areas so as I said really big long-term issues at this site that continue to persist. I mentioned before that 7 billion tonnes of tailings that are produced globally each year and obviously the amount of tailings depends on the total production of the ore as well as the quality of that ore and how the different ores are processed and so you can see on the right hand side here some numbers around how much tailings some different commodities produce so the chemical and physical properties of these tailings is a bit different depending on which commodity they come from but we can break some of them into some groups and by doing that we can start to identify some common properties that we can use to develop remediation strategies for these so one strategy for example that we've been working on is aiming to treat the alkaline pH in about 25% of the tailings produced worldwide regardless of the by-product or tailings material waste rock whatever you want to class under this produced we tend to apply this by-product remediation sorry management hierarchy so to write down the bottom is discharge we don't want to be just discharging these materials unremediated into the surrounding environment the next tier up is containment so simply confining and controlling any potential releases of those tailings and wine waste next tier up is remediation so what can we do to actually change some of those hazardous properties of the tailings so that even if they are released they're not going to cause any issues to surrounding environments and how can we safely close these tailings storage areas reuse so what can we do to create some other opportunities so that we can feed these in as raw materials for other processes and finally the lofty goal of zero waste so this is a bit of a moonshot requires a lot of thinking about how we redesign our mineral extraction processes and it requires a lot of effort from engineers from environmental scientists from materials chemists all kinds of different expertise to feed into that although this is a little bit of a way away uwa is definitely working on trying to achieve this and I'm just going to give a quick plug for an event that we're organising in about a month's time called three steps to an affordable zero waste mine we're organising this in collaboration with the public policy institute and the minerals research institute of western Australia we're going to have a panel discussion looking at this issue from all different angles so from the mining sector from the regulators perspective from non-government organisations from research and development and try and understand where are those opportunities to make this a reality so we've mostly been focused on these three levels here at the moment like I said zero waste is still a long way off we have made some good progress in these three levels here and what I want to give you is an example of one of the projects that I've been leading that has gone from this level down here containment and now is working towards developing strategies to empower reuse so we've been answering three main questions here number one how can we make containment safer number two how can we make remediation faster cheaper and achieve better post closure outcomes and number three what are the opportunities for reuse and how do we develop these new materials and markets for them this is an aerial photo of a bauxite residue deposit in ireland and a bauxite residue in its management is quite important to western australia where one of the world's biggest producers of bauxite and a lot of other products the challenge with this material is that it's quite alkaline and it's quite salty and so as you can imagine when it comes time to close and remediate these deposits it could be a real challenge to get plants and animals to come on site and get that ecosystem started so what our remediation strategies have been focusing on is understanding how we can accelerate that process this is a photo of a site a bauxite residue storage area in Guyana in South America it had been left for about 40 years with no treatments applied whatsoever and when I visited in about 2010 we noticed that this vegetation cover had naturally started to recruit onto the site and that was really interesting because it told us that the tailings could almost remediate itself it just needed a really long time and so obviously when we're trying to close the site we don't have the luxury of time on our hands we want to be able to do it as quickly as possible what we did is we studied the properties in the vegetated and non-vegetated areas of this site and indeed about 10 other sites that have received different kinds of amendments all around the world to understand what were the critical factors that impeded or enhanced remediation and vegetation growth so in other words what were the treatments that we could apply to decrease pH and reduce that alkalinity and get rid of all the salt and what we saw were that in areas with high rainfall and areas where physical amendments had been applied we saw a rapid decrease in salt when we applied chemical amendments and in areas where there'd been a good atmospheric carbonation we saw a decrease in pH and so combining those two together where we saw all of those acting we had the best remediation outcomes because they were addressing the pH and the salt at the same time but what we started to suspect was that microbes could play a role as well no one had really looked at the biology of these deposits and what we saw by doing some work at another set of sites and starting to characterise microbial community was that in fact we saw hints that microbes were helping to neutralise pH very rapidly by using organic matter that had been supplied there was also some evidence that they could help fixing the carbon dioxide and reducing pH as well and so based on that observation we set about a package of work designed to essentially generate acids in situ with those microbes now for those of you who are familiar with the beer brewing process this is pretty much it right you feed them some glucose you figure use some glucose and they produce ethanol and carbon dioxide the process that we tried to do here is more or less similar except we want them to produce acid rather than the alcohol and by adding a little bit of soil by giving them some glucose as their food source and introducing all that into the bauxite residue we were able to come up with a treatment that rapidly decreased the pH of this material we could also see physical changes so you notice this suspension before the treatment and after the treatment you can see how clear that solution has become and that's because all those fine particles have agglomerated and dropped out of solution we've improved the structure as well after we'd tested that at the lab in little vials containing about three or four grams of the bauxite residue we started to scale up so the first scale up was to glass house where we neutralised about 30 kilos of bauxite residue at a time and what we did here is we tested this microbial treatment as a way of producing acids and carbon dioxide with some of the other treatments that we've seen in that previous fieldwork that enhanced remediation as well so adding organic matter adding irrigation to simulate the higher rainfall environments using tillage to create structure and help with leaching and adding gypsum as well to stabilise the structure and decrease pH and this combination was a highly successful approach for driving rapid pH neutralisation as well as salt removal through leaching from this material from these glass house trials we've now set up a medium scale field trial here in western Australia and we continue to work with the Illumina companies to further develop this approach our next stage we'll be looking at putting plants on and how we can then build up ecosystem complexly further from there and what we're also considering as well is how this approach for remediation of tailings is going to potentially empower new reuse avenues as well so at larger field scale what we're considering is adding all of these amendments at the surface mixing them in and then periodically going back and harvesting the treated residue by being very careful about which kinds of amendments we add into the residue we could tail the composition of this soil product and open up a whole new range of reuse opportunities and what we would potentially be able to do would be treat a layer towards the top of the deposit remove it treat the next layer remove it and treat the next layer and remove it and so in this way the strategy that we've developed for remediation would actually empower reuse and removal of these tailings storage facilities over the long term i'm just going to quickly showcase some other uwa research in this area that is part of this overall feature of improving environmental outcomes associated with mining the first is looking at how do we improve revegetation outcomes focusing more on the plants rather than the soil part Australian native species are really challenging anyone who's tried growing them in their garden will know how tricky they can be and how fussy they can be and certainly rehabilitation that's no different at all these are some photos from up in the pill bra big iron ore mining regions where some of the trials are going on at the moment Todd and Andrew have focused in on key species here that are challenging to revegetation and by understanding at a very detailed level their seed morphology they've identified new treatments to enhance revegetation so you can see one of the seeds of their focus species here has this fuzzy coat and these legs out the end what they've done is designed and engineered a flash flaning tool that burns all of that material off and not only does this improve germination success so the number of seeds that germinate but it makes it easier to spread across the site as well to get more vegetation more easily evenly spread across your site this was such a breakthrough it has had such success in improving revegetation outcomes up there that actually won the 2016 Western Australia Innovator of the Year award near merging innovation category as I said Andrew and Todd are leading this project and I'm sure they'd be happy to answer any questions that you might have about this approach another area is around improving our understanding of endopit lake chemistry and physical properties so that we can intervene before some of those issues like the acid mine drainage at Mount Morgan that I mentioned before become an issue the approach that Carolyn and Matt have used to address this is by going out and collecting very detailed field data using these long sensors that they've installed across the lakes to create a detailed understanding of the chemical and physical properties of these water bodies model inflows and outflows and create a detailed computer model so that they can predict when things might go wrong by being aware of when things might go wrong they can then intervene before they do go wrong again Carolyn and Matt leading this project and I'm sure they'd be happy to answer any questions that you might have about that finally completion criteria so much like in football we need to know where the goalposts are if we're going to actually score completion criteria in mining talk are talking about agreed standards or levels of performance which demonstrate a successful closure of the site so during revegetation we need to know what are the key targets that we want to hit so that we can wrap up our work here these completion criteria are not easy to define in practice obviously there's a lot of variation on the site by site basis and there wasn't any clear guidance for how a company should do this often people would just borrow completion criteria from each other and they'd be applying them to totally different ecosystems or parts of the state and so what Marityn Anna did with as part of a larger team was go through a big consultative process with a lot of mining companies government regulators community groups and university partners and come up with a detailed framework only a small part of which is shown on the right hand side here to improve that guidance on how people could develop criteria that were appropriate for their sites again Marityn Anna I'm sure they'd be happy to answer any questions that you might have on those a couple of other projects that UWA is involved in so one's a cooperative research centre for transformations in mining economies this was announced early this year it's a 10 year partnership with 130 million dollars of research support across all of these different partners being contributed and this is really focused on figuring out how we can early in life in the life of mine be able to design strategies so that communities are left with positive economic and environmental legacies after mine closure we're also involved in training the workforce of the future so I mentioned that field trip right back at the start of my talk these are some other photos from that trip so going around various different sites in southwest western Australia we also try not only to get people to talk to the mine staff on site we've been very generous in sharing their expertise with us we get them to collect samples both in the field and process samples in the labs that they have really detailed understanding of the kinds of materials that you find at mine sites and what can be done to remediate and reuse them a quick plug for our master environmental science we have an environmental rehabilitation specialisation within this program and the specialisation the specialisation itself is broad so we look at urban mining and other environments but within that there's a couple of units for any of you who might be interested in training and development opportunities they're particularly relevant to the mining industry and of course I'd be happy to take questions or emails from anyone who's interested in enrolling in those and with that I will wrap up and hand back to Sam to go through any Q&A again anyone who's interested in coming along to that event please register your interest at that email address thank you that's great thank you so much Lisa that was such an interesting talk we've had loads of questions come through so I'm just going to pick a couple for you to get going with it that's okay first question is from Fran and this is something I was thinking of as well so it's how long does it take for waste material to become functional enough to support flora and fauna in that environment that's a really good question so like I said in Guyana in South America we were seeing that it took about 40 years and that was in the do-nothing case right we've seen similar sorts of timeframes for gold tailings there was a nice study a while ago of some gold tailings in Canada that took about 40 or 50 years before we were seeing some nice vegetation come on to site without any amendments what we're trying to do here is compress that timeframe to five years if we can get it shorter than that that would be fantastic so far we've had really good success with that treatment that I talked about for bauxite residue we're definitely compressing the soils part of it to one to two years and the next challenge is to then compress the vegetation and developing those more complex ecosystems into a two to three year timeframe perfect and yeah just to remind everyone if you want to ask questions just use the Q&A function at the bottom of your zoom window a question here from John so John says that zero waste is obviously an ideal but if we were able to remediate and reuse everything instead would that still have an observably positive impact on the local environment absolutely yeah especially if we're able to use strategies like the one that I discussed to draw down any reserves of those byproduct materials that we might have at mine sites and eventually remove them from the local landscape altogether that would definitely be the ideal if we can remediate and turn that part of the landscape with the byproducts still stored to a productive endland use then that's definitely a great outcome as well so I don't think you know zero waste although it's the ideal isn't always necessary in order to have a positive post mining outcome no absolutely and a question here from Alicia who says does anything need to be done to maintain the top soil while it is stored yes there has been a lot of work done around top soil management in the earlier days of mining people would not really think about it much at all and scrape it off and mix it with overburden and you know not give it any special treatment at all and once people realised how valuable top soil is as part of rehabilitation it got treated much much differently so now what we do is we try to do a thing called direct return which is obviously as you go through your life of mine you'll open up a larger and larger part of that resource often you'll have opportunities to progressively rehabilitate as you continue to mine as well and so what direct return is is when you open up a new part of the mine you want to try and return that top soil immediately to a part of the mine that's being rehabilitated that's the ideal if that can't be done then we try to store top soil for a shorter time as possible because its quality does the grade quickly great i've got loads of questions coming in so another one here from Todd so Todd says with the potential benefit of using soil microbes in this remediation space e.g for tailings where is the research at and crucially is this scalable as well yeah so the strategy that I presented that's a great example of scaling up so we started in the lab with three or four grams of residue we went to the glass house where we were treating sort of 30 to 50 kilograms at a time and now we've scaled up to the field where we're treating 35 tons at a time so that's a seven order of magnitude scale-ups we've been really really pleased with how that's worked and that's not the only example either there's some really nice examples of inoculation onto seeds that have been successfully scaled up from laboratory through glass house into the field as well what was the second part of the question just about it was just about that exact question about scale which was answered perfect so another question here from Kylie I think this is quite important do we need innovation in repurposing to enhance adaptation and value or communication to educate more broadly yeah these are some of the issues that we're going to cover in the three steps to an affordable zero waste mine event so it's both of those and it's other factors as well so it's looking at not only consumer attitudes it's producer attitudes how they can change their processes that might make it slightly easier to reuse or that we might open other opportunities for reuse it's looking at the regulation it's looking at how we not only change policy to support this but also how do we change various levees and economic incentives how do we address issues like freight so that's a massive one believe it or not trying to get these materials from where it's produced to where it could potentially be reused is really challenging and some people have got great ideas about how we can backfill onto grain trains and things like that so it's a whole bunch of different factors and we're trying to figure out some solutions where the opportunity is as part of this event up on the right hand side excellent and a question here from selesi i think which kind of backs onto that is what to what extent do you think the mines are actually willing to to engage in in these conversations themselves and the the responsibilities that they identify as having yeah very willing i've been very pleased with how supportive how engaged how interested most mining companies are with figuring out ways to reduce the environmental impacts of mining and i think that's because as i pointed out at the start of my talk mining companies know that they have to be managing their environmental impacts as best they can if they want to continue to operate so not only from a regulatory perspective there are of course avenues for governments to step in and revoke licenses if environmental management measures aren't appropriate or aren't achieving their aims but it's also from a public perspective as well so i mean they know that their social license to operate is so important being welcomed as part of local communities who are often keeping an eye on those environmental impacts so yeah with that in mind i've had very supportive interactions with mining companies on these topics that's really good to know i mean i think you've definitely inspired some people to be thinking outside the box here so a question here from Steven on this issue of repurposing the acidic lake was primarily acidified by the production of sulfuric acid he thinks that's what you said yep could this be could this be used as a starting material to be used in the manufacture of fertilisers and has anybody thought about doing this it's also used in dyes pigment production and some explosives for example yeah absolutely so um spot on it definitely is the challenge that we have at the moment and that there has has been and continues to be a lot of work on is how to separate out some of those other components as well so i didn't go into this just for the sake of time but um when you have that pyride oxidising you often i wrote it there as a pure mineral but it's often not it often has copper cadmium all kinds of other elements mixed into it and so when the pyride oxidises not only does it generate the sulfuric acid but it releases the iron it releases those other elements as well and so that water is a soup of different elements to be able to use sulfuric acid for some of those applications you actually need a pretty high quality product so the challenge is how do we purify that acid or can we find some applications which are less demanding on purity so that we could reuse it for those sorts of purposes fantastic i think we've got time for one last question this is from francis um and this is just what is the evidence around the impacts of decreasing mine wastes on environmental assets are there for example biodiversity measures or other signals that indicate recovery or no harm sure so i'm going to assume um that that's uh in relation to pre and post remediation yeah the monitoring schemes um there's some guidance from the government but the monitoring schemes are often proposed by the companies and then reviewed by the government so that they're appropriate to that site and its environmental context as well as what is the inland use that you wanted to support so for example are you trying to create a site that supports pasture or cropping or that would be used as a recreational area or any other sorts of land uses so they're often those monitoring schemes and the completion criteria are often tailored to the site and its unique properties fantastic all right well that's just about time for questions uh tilitha so we'd just like to sincerely thank everyone who's attended today's session a special thank you to tilitha for sharing such exciting research that her research group specializes in uh and for figuratively at least taken us across the border to Queensland to see what mine sites look like over there as well and in great to see some of the UK in that talk as well if you've got any questions for tilitha please do reach out to her via email or via her twitter handle there as well and we look forward to seeing you all next week for some more science exchanges thank you very much goodbye