 Well, hello everybody and welcome to another one of HydroTerror's webinars. Today's topic is all about water quality, specifically sensor selection for your water quality monitoring applications. So today we've got two people presenting myself, Richard Campbell, who I will be talking a bit about water quality and the need for data provenance and then also touching on the need to be able to integrate such technologies. And then we'll be moving to Ryan Cox, who's sales director from Aquaread, Aquaread are a company that specialise in water quality instrumentation. Ryan will be bringing a wealth of experience from his career working with instrumentation manufacturers and dealing with various application challenges. Here's a picture of Ryan for you and a picture of myself. So before we get started, a few administration things to be aware of. So we've got a lot of people here today, which is fantastic. The thing we really love about having a lot of people is getting lots of questions and we hope to answer them today. So to put a question in for me to address at the end of the webinar, please click on the Q&A button at the top of your screen and register a question in there. Please don't use the chat function. Otherwise, we've got two sort of lists that we're trying to manage the Q&A button is the one to use. But looking forward to getting your questions. Why does Hydrotera run these webinars? There's a few purposes. We like to share knowledge, not only our knowledge, but the knowledge of our broader supplier network who have, you know, really strong specialised skills in areas such as instrumentation, engineering, etc. So it's often great to get their expertise into this and they come from all around the world. We believe in education and we believe in educating the broader industry, particularly a lot of our consulting customers who may be fairly new to the industry and are wanting to understand better how to measure things. Finally, we want to be able to lead a leader in the industry. We're developing a marketplace for environmental monitoring and we see a really important part of that is to make you aware of what's happening in the world of monitoring and environmental monitoring to keep you abreast of any changes that are going on there. So what are we covering in this webinar? So as I mentioned, I'll be looking at the importance of data provenance and also looking at just holistically what are the various options that exist, right? Then Ryan Cox is going to be a lot more focused really around the sensor side of that water quality monitoring paradigm. And he will be running through a series of technologies that they have, but also, you know, the challenges when to use which particular types. And really when you look at the bottom end of that list, the really important side of things, calibration, validation of data and I would add in their maintenance. So it should be a very informative session about all things water quality. Alright, so data provenance frameworks and measurement methods, what is Richard talking about? So data provenance is really when you have a measurement that something's created or a data point, you know, electrical conductivity would be an example. Can we really trust that number that's in front of us? What's led to that number? And I just wanted to bring your attention to a document that's been developed by our Bureau of Meteorology that's excellent, really discussing everything to do with water quality metadata. And ultimately that means provenance of that data. And if you look at this schematic, which is really a, it's a slightly bastardised diagram that we use a lot from the Bureau. It shows the elements that make up any particular monitoring number that you're dealing with. So you might think, oh, I've just got my number out of my instrument. That's all I need to think about. But the way the industry is evolving, auditors and the like are going to be wanting to know more and more about what produced that measurement. Can we trust that measurement? So in this diagram, you'll see typically we have a monitoring site. So a site is actually not a measurement point like a well. It's typically something like a landfill, for example, that would be your monitoring site. Then you have a series of measurement points, monitoring points that are across the landfill. So this might be a bunch of groundwater wells that you're doing water quality measuring from. Then you have a sample. Now a sample is not exactly what you think is a sample. A sample can just be a measurement with a sensor or it can be a collection of a sample that goes to a laboratory. Sometimes we group those measurements together into what we call sample sets. It's really important to think hard about what water quality samples really do go together. Are they from the same aquifer, for example? We then have results. Obviously, we get our results back at what's the provenance been? Well, already you're creating a bit of a framework. It's come from this site, from this particular monitoring well, sampled on this particular date, and we have this result. An important part of things is then, well, how do you actually report that particular parameter? So often I see people use various instrumentation that we have, which gives multiple choices around water quality. They might be percentage saturation or it might be milligrams per liter. And people are not quite sure which units to use. Well, it's important to understand the methods that sit behind this and also to understand what the appropriate parameter units you should be using. Now we can help you with that. We tend to develop up what we call measurement methods to make sure we've got a consistent way of doing that. But there are also various standards in the life that are produced by organizations such as the Bureau of Meteorology. Why is the Bureau of Meteorology of interest to us? Well, they have national responsibility for monitoring, not just the weather, but also various water resources around the country. So they've had to look very closely at this and develop some national standards for recording of this kind of data. So I just thought it would be useful for you to know that. Lastly, it's good to have technical references to back up any result that's produced. Lastly, that technical references. Okay, this is the manual that was used or this is the particular Australian standard that we used for how to deploy that particular sensor. I've added that box called measurement methods because that's what we use in hybrid. We sort of create a consolidated document, which is a combination of standards and what we know from, you know, suppliers, manuals, etc. to create these to make life a bit more manageable. But at the end of the day, you need to be able to provide a documented pathway and you need to understand everything that sits behind that result that you're getting. So the Bureau has created a really nice framework to do that is what I'm letting you know. So have a look at that document, the National Industry Guideline for Water Quality Metadata. I've found it very useful. Next topic I thought I'd touch on relates to, you know, how can we measure water quality these days? And trust me, it's incredibly diverse. Okay, so if you look at this left hand column of this schematic, this is data collection sources that can be related to water quality. Now, this is a schematic out of one of our projects. So it's also project specific, I suppose, on what I'm saying. But we have sensor networks. Okay, so those sensors can be mobile or they can be fixed in their locations. It's important to be able to ingest both data that might be being collected by someone walking around and carrying and measuring at multiple points. But it's also good about a deploy to have fixed points where we have continuous monitoring and we can look at trends. In the end, it's the trends in the data, which I think are most important. We're seeing more and more drone mounted sensors. You can actually mount water quality sensors to drones. We've got drone boats, which we can use to go out and collect, you know, 500 waypoints across a water storage and produce that data as spatial plans. Others use drones to go out and collect water samples from things like tailing stands. We need to be able to think about how to bring our water quality data back by things like drones, aerial and boat, for example. Then we have digital forms. Now these are really becoming very popular and quite powerful. This is where you might have a spot measurement that you're taking in the field that you're wanting to ultimately ingest back into a data storage. Well, setting up your templates right that match your particular instrument that you're using is a great way to make sure you're recording the right parameter in the field rather than having people reporting different ones. If they're working on different parts of the same site, which sometimes happens, it's good to have all of this templated. The next one down is cloud based data sources. So what does Richard mean by that? So these are things like, you know, natural resource management organisations have their own continuous water quality monitoring sites. And that data might be hosted on a website, for example, and you might want to be including that in your water quality monitoring program. Well, these days we can link to those various data sources via what we call API links, and that allows us to bring that data back in. So when you're doing a monitoring program or designing it, always keep in mind that it's not just the data you collect, but the data that others have collected that you might want to use that becomes useful in that sort of context. One thing that's really growing strongly is the application of satellite data. Okay, so remote sensing and CSIRO has been working on a program called, I think it's called water quality from space. They're looking at how we can use the satellite data better to look at water quality. So one area where that is relatively easy to do is where you're looking at things like turbidity, because obviously the water colour changes a lot. So you can effectively look at your light penetration from space. And that's quite powerful, right? The other thing to remember is with satellite data is a lot of the data goes back to the mid-1970s. So you can suddenly have a really good water quality time series data set based on those original measurements that are still occurring to this day from some of our geostation satellites. So great set of data there for long-term trends. Unfortunately, fairly limited sort of water quality parameters that you can get from that, but it's growing. It's growing. Open source data, that's pretty much the same as what I described as cloud-based data sources. I actually probably explained cloud-based data source a little bit incorrectly before. So I think I was describing more open source. So cloud-based data sources, a lot of sensor-based manufacturers these days also have their own clouds. So I know Aquarets working on having its own cloud. So that's where data comes out of your sensors via telemetry and is hosted in the cloud. So it's possible to link that so it's effectively continuous coming into another database using API links. So a number of hydroterrorist suppliers have these clouds and part of what we do is link them up and ingest them into our own cloud, which our customers then use. Then we have laboratory data. So lab data is still critical in many, many situations. And it's important to think about the rigor that goes around any lab analysis. So people talk about Nata accredited results. Well, Nata is a process. It's an organization that accredits processes. And what that means is that any result you see for lab result, which has got a Nata stamp on it, we know the provenance of that analysis. It relates to a method and we've got a result with known uncertainty around it. So a lot of the legislation in Australia, you know, laboratory analysis must be undertaken by a Nata accredited laboratory. What it means is the methods have been accredited and their processes have been accredited. What I'm trying to say, I think to you guys is, wow, what a broad number of ways to collect water quality data. But in the end, you need to know you can trust it to the same level that you can trust a piece of laboratory data. Because in the end, you're making interpretations on that data. So the way we do that is with that provenance framework that I showed you on the previous slide. And the way Hydrotera helps you is we create those provenance frameworks on a site by site basis. And we federate the data from these various sources into a common data storage and access portal. So that's a little bit about how broad water quality measurement can be. Today's speaker, Ryan Cox, has a lot of experience with that top left one, which is really sensor based instrumentation. He's worked across the industry for many years and we're about to hear him speak now about what Aquaree does in that area and the sorts of things to be aware of when you're deploying sensors. So without further ado, we'll hand over to Ryan. Hi everyone, my name is Ryan Cox. I work for Apple Read. It's good to be talking to you all this afternoon. So today I'm going to talk to you about our products. I'm going to talk to you about our sensors. I'm going to talk to you about calibration or give some calibration advice. I'll just point a few things out in terms of our sensors. I'll give you just a quick overview of what one of our multi parameter packages looks like. And then at the end we'll just show an example of a calibration video, all of which are available on our YouTube channel should you need to calibrate any of your products in the future. So this is our current range of products from our Aquaree range. We did produce water level sensors as well and we will be releasing some new products very shortly. But this is the mainstay of our current multi parameter water quality range. So from the left we have a product called the AP Lite, which holds a single parameter, a single optical sensor from a range of sensors. Then we have the AP700 and 800, our more budget line product which just houses standard parameters and one optical sensor. The AP800 comes with turbidity, some of you may use that. The AP2000 which is our more advanced multi parameter instrument, so it's a 42mm probe, meaning it goes in a 2 inch monitoring well. Hence why it's very popular for groundwater monitoring applications. That comes with optical dissolved oxygen. Then we have the AP5000 and AP6000. The 6000 comes with a wiper, the 5000 does not. Then we have the AP7000 which is our current flagship probe. The reason it's the size it is is because it houses six additional sensor ports or sensors. In addition to the 13 parameters we include standard and our multi parameter probes. That as well comes with a centrally mounted removable wiper in the sensors before a reading is taken. That's what our range looks like. They're made of marine grade aluminium so they're pretty hardy against the elements. And they're anodised as well for extra protection. This is our list of sensors that are available from us. So as the previous slide said, made in Britain, all of our products are made in Britain and that includes our sensors. Our sensors are our own design from the optical dissolved oxygen sensor to the pH sensor right through to the CDOM sensor. They are our own design. So that's a rarity in this industry. Some manufacturers do, some manufacturers don't. The manufacturers that do make their own sensors is very small and we're proud to be one of those. The good thing there is if any issues arise or you need any technical information, we know our sensors inside out because we design them and we can give advice and guidance very quickly. 99% of our advice and guidance is covered from some basic things which I will discuss later in this webinar. So our standard parameters on the left are included with all of our multi parameter probes. The only choice being optical or galvanic depending on which probe series you choose. Then the optional ones are in the middle column and then the right column. So you have a range of ISE sensors or ion selector electrodes which you can choose. And then we have a range of optical sensors as well. And these sensors cover 95% of applications that we see. There are some specialist sensors which we don't manufacture. We leave those to the companies that choose to specialize in that field. But as I said, 95% of what you would expect to see from other companies or other instrumentation you might use, you should see from us and you might see a bit more in our range. So generally a high proportion of monitoring applications involve PHORP, so Oxygen Reduction Potential PH, and then they will include dissolved oxygen and they will include EC. So I think parameters are usually, in most cases, the desired chemistry that is measured on a range of monitoring projects. Then from time to time, additional parameters are measured. So as technology has moved on over the last 30 years or so, more sensors have become available, meaning that lab tests for stuff like turbidity or for stuff like, I don't know, Rony, calcium chloride, whatever, from those lists are now possible with multi-parameter instruments. When you're choosing one of those sensors, there's a few things to bear in mind. So you need to bear in mind the range or the physical limitations of any sensor, not just ours, any sensor you might buy. So any one of those sensors there will have a measurement range. So it might be from 0 to 10 or 1 to 100 milligrams a litre, just as a broad brush example. And you need to make sure that when you're given your specification by your consultant or by your local authority, for the measurements you need to take, you need to make sure that those sensors meet that specification. These sensors also have an accuracy. So the accuracy is basically how valid are those readings. And usually for an ISE sensor, it'll be 10% of the reading. And then you go on to what's known as repeatability for an optical sensor. So it's worth just looking at those and making sure that that finite accuracy is what you want. If you're looking for very, very small concentrated chemistry changes with the highest level of accuracy, it may be that a multi-parameter probe is not suitable. These really give an indication of chemistry. They do not give a quantitative analysis. They give an indication of the chemistry they're actually monitoring. And it's important to bear that in mind. Usually, as I'll mention in a few slides time, a lab test is done in support of taking measures from a multi-parameter probe. And in certain circumstances with a very good calibration and good laboratory practice, we've got our accuracy percentage of our ISE sensors to 1%. We actually quote 10%. So you can see there's a wide degree of error in that. We quote 10%. And the reason we do that is because we try to account for errors in calibration, very cold temperatures. Because a lot of the accuracy is quoted at either 20 or 25 degrees as well. So it's worth bearing in mind that if you come down to like 5 degrees, well, the readings will obviously won't be what they would be as accurate as they would be at the calibrated point. But then the meter or our handheld meter will account for that from the readings that you are moving. So I think the takeaway point from this slide is that's the range of sensors that we offer. It's quite an expansive range. But when you're choosing like a turbidity sensor, for example, it's worth looking at the minimum level of detection. Or if you're looking at an ISE sensor or a standard sensor such as pH, it's worth looking at the accuracy and natural measurement range of what that sensor can physically do. This is an example or two parameter setup of ours. This is just a product chosen at random with no particular relevance other than just to demonstrate what our product looked like. So you'll see that this is in a package for that. All of our products are offered in a package and we include all of the standard parameters in the price. So the price you pay will include those standard parameters. We don't charge extra for those. All you then need to do is choose what additional sensors you need for your project. So with our products you can see here where the pointer is the moment on this picture, the sensors included. So we have DO and EC and we combine that sensor to save space. PHORP, which is a combined electrode or combi electrode. And then we have four sensor ports. So you'll see here that it has forum restricted ports. These sensors can be retrofitted at any time by you, the customer. So you do not have to specify this probe with the sensors you need. So it adds a degree of versatility. Because if you buy this for a project but then later on down the line you move on to a new project and you need a different optical or different ISE sensor, you can just buy that with sensing. And as I said, we include everything that you need to get going. So if you buy it as a package, it comes as depicted here. That is enough to get going. All you would then need to do is choose your sensors for your project. So this is an example of some of the applications that our projects are used in. Low flow being really the most relevant based on the previous presentation that was done by Solids. 400 errors and I thought I'd try and carry on from that vein. So we do low flow sampling to take water from the ground or water from the surface in a river or lake or whatever. Different sampling methodologies are used. So there are a set of companies that make that instrumentation. We make obviously the instrumentation for water quality and level measurements which are obviously carried out afterwards or after the samples we would take or whilst the sample has been taken in this case. So low flow sampling is great because it doesn't disturb the sample and that makes it very good for a water quality probe to take good measurements. If the sample was disturbed, you might have sediments in there or you might have gas in there or you might completely mix up the chemistry. So in doing so, the readings may not actually be truly representative of what's going on in your water well or in your aquifer. So a true representation of low flow sampling is it samples and represents ambient conditions in the well. So you don't need to do three bulb volumes with a baler or an inertial tube which would mix that sample. You're not mixing the sample. Routinely done with a flow cell. So the water would be pumped out probably with a bladder pump or a valve pump in certain conditions. And it's very good, especially with a bladder pump. If you're looking at things like dissolved oxygen or you're looking at stability or any other chemistry, it doesn't aerate or dilute that sample. So it gives a very nice and stable flow, stable sample that allows you then to take a stable reading from any of the senses. Routinely, sampling will be dictated. So you'll have a schedule of sampling from your regulator or from your consultant and they might say five minute sampling intervals. So you'll sample for five minutes and then take a reading or 15 minutes, whatever. That's usually dependent on your like EPA guidance as well or your environment agency guidance as well. So but our meter and our probe is able to work from that so you can set logging, so you can set the log in for 15 minutes. Once the parameters are all stabilized, you will hear a B permitted and then up and down arrow will be indicated to show that global stabilization, all the readings are stable. So that's, you know, these products are designed to work in a low flow condition where you need to have that indication of stability and you can program our meter to work in that way. The only thing I would mention is sometimes it is suitable to have a wiper in a flow cell. So, you know, flow cell is a controlled environment in as much as it's a known sample of water and it's coming from a bladder pump. You know, we know how good bladder pumps are for that kind of sample but if there's lots of sediment in there or if there's some gas in there that can create air bubbles or there's some sort of aeration from some chemistry or whatever that can affect the readings because what the probe will then do is it will measure those air bubbles as chemistry or as, you know, as stability, for example or sediment will blind the electrodes and cause the readings to rise. So having a wiper before it takes a reading it will clean all of those sensors, clean that sediment off, clean those air bubbles off and then it will only measure the actual water depth from chemistry rather than measuring the chemistry and the air bubbles and the sediment which can cause the readings to rise. So we have two wiped probes in our range and it's important just to bear that in mind when you're using that kind of setup in a low flow environment. This is an example of a wiped probe. So this is an AP6000 which I showed you in the beginning slide and you'll see where the pointer is now, it has a wiper. So wiped probes are great for long-term monitoring and for, you know, low flow sampling where you have sediment or air bubbles because as I've said, they clean the sensors in turn. This would clean the other sensors obviously over there and this picture is just for demo purposes. This wiper from our design can be removed and replaced by either the customer so if it becomes damaged, you can replace it. You can also replace the brushes. You can move that split ring there and you can replace those brushes once they wear down. That generally takes quite a while but we've designed in as such that, you know, this product really needs to stay in your hands the customer for as long as possible. So with the wiper and with low flow, you would have flow cell. So I mean some customers might use a bucket but generally a flow cell is considered to be better than that. So the probe, the AP6000 in this case has a little collar and that then screws down into this cylindrical flow cell here. You'll notice that the flow cell is black and that basically stops any stray light from getting into the measurement chamber because what you don't want is this probe deployed on surface. It might be a very sunny day and then you'll get stray light entering if this was clear and this will then affect the readings particularly if you're using an optical sensor. So this goes in and of course you have your inlets and your outlets there as well. Some customers might have on their sample input line they might have a little T branch and they might open that and put that through a filter if they're taking metal samples or they might decant some of the sample through that little T outlet to take into a sample pop and then send to a lab. That's all stuff that is routinely done alongside our products. Spot measurement as well. Spot measurement is a very common application for us. So this would be done where you don't have any sampling instrumentation. You just take your package as there and then you just lower the probe into the watchbox and take a set of readings. You need to be careful obviously you don't mix the sample because both local sampling is fantastic. It can be expensive to instrument yourselves and the project but obviously certain chemistry really doesn't need to be measured in that way. Some customers choose to do spot measurements but you should be careful not to mix that sample up because then you are going to get the readings. There'll be a degree of error in those readings. The sediment will blind the electrodes. It's really important. Lower that probe in gently and usually in the monitoring guidance from the EPA or the US EPA for example, they do give guidance on taking spot measurements with water quality approaches. It's important just to look at that because they'll dictate how and when the sample should be taken once you start your monitoring program. Then with our probes you can plot the GPS coordinates. If you wanted to do chemistry profiling you weren't going to do that in a well and you want to walk along a river as is the case here in the UK. You can plot the readings on Google Earth and Google Maps. Our handheld meter includes GPS as standard and you can see here data was downloaded and these different pinpoints will represent different chemistry. Obviously there's been a pollution event or whatever taking place and you'll see the chemistry. The picture's rather grainy but you'll see that the chemistry is listed. You can take that into geophysical software or whatever. Some customers provided quite a bit of their work and their reports for customers. Long term deployment. Long term deployment has seen a major uptick in popularity because of the pandemic. Our products can be used for long term deployment. They can also go on to telemetry. That is usually what happens once probes get deployed. Our probes operate for roughly 10 months on a set of alkaline batteries and can record 150,000 sets of data. But they do still need to be calibrated. Obviously the probes work all the time. So usually if you're looking for like a, you know, you'll have like a pH rise or a DO rise or it might go low or salinity or EC rise or it might go low or whatever. You can do event based monitoring with our probes. So the probes work all day. They don't have to go home and sleep and you know, take care of their family. They're deployed all the time. They're monitoring all the time and they can be set to look out for those events so they can take lots of data whilst that event is happening and then return back to their normal usually 15 minute readings once that's been done. So you do have that versatility with our probes as well but you do still need to calibrate them and they're deployed long term. That's an example of what data would look like online. So a lot of customers do go down the telemetry routes. Obviously you'll have data at a glance and we can validate. At cloud-based web port and telemetry device there's an option with our probes. So just a quick note on calibration then. So by far the most important thing for our probes is calibration. If you don't calibrate them properly they will not give you good readings. 99% of the problems with our sensors come from poor calibration or poor GLP or good lab practice from the laboratory practice. Probes are generally very easy to calibrate but you need to vary your calibration regime to meet the dictates of your project. So if you're expecting extremely high accuracy in your readings in your probe or you're looking at a very sensitive project where the measurement of the chemistry is as sensitive you would need to be doing a full 3-point calibration for PH a 3-point calibration for your ISC sensor a 2-point calibration for your telemetry sensor. It's important to get that right because then you're giving the probe everything it needs you're giving it a full linear range of calibration so then the readings you take will be appropriately matched to the accuracy that you need for your project. It's a good idea to do daily spot testing as well so RapidCal is a great tool to do that. I wouldn't personally recommend that you use RapidCal and RapidCal alone because it only calibrates PH at 7 and EC at 2570 so that's not necessarily ideal for sort of a everyday calibration but full calibration should be carried out but it's good to just quickly do a spot check and that spot check should usually be recorded. Customers do ask how often they should do the full calibration my answer is always it depends how good you want the readings to be so usually once a week is sufficient some customers do it once a month obviously it is down to your personal preference it is always good to have up-to-date calibration solutions and been open for too long and practice good GRP as well clean the probe and deionise water don't calibrate it in it's got mud on there or dirt from your chemistry on site clean it off and just use deionise water only some projects require a manufacturer's certificate a calibration a hydroteric can do that on either half it's important to check if you need that at the start of your project some customers do get caught out and their client will be the readings you've taken how do you know they're as good as you say they are how do you actually know that probe and what you say it's doing well the hydroteric can support you in that they can do a calibration to ISO standards and produce a certificate or we can do it if that is your preference but it's worth getting that in place from the start rather than having to backtrack at a later stage in your project this slide just indicates a couple of things once you calibrate it so if you want to validate your calibration a lot of customers say how do I actually know that that probe is calibrated how do I actually know how good it is calibration is it actually reading what I think it's reading some customers debate a lab analysis in support of readings they might take with a multi parameter probe but it's worth bearing in mind that a lab instrument a lab will be working to ISO standards and their instruments will be calibrated according to them and they usually while they're always almost certainly in a very controlled environment but if you take a ruggedised field instrument and you expose it to the elements and the outdoors differing temperatures you know mixing of chemistry especially if you're doing surface water you know some of those things may not happen or may not appear in a lab environment it's worth bearing that in mind it's also equally important to as I said in the previous slide make sure that your calibration meets the dictates of the project because if it doesn't that is usually where all of the issues come from when the two readings are compared from our lab from the probe but one further point of validation you can make is to look at the offset of the calibration slope now these readings might not mean necessarily anything to you at the moment but if you look in our manual you can see the different slopes and rate of offsets rather of the calibration so you can have an indication from us the manufacturer as to what is good and what is bad and HydroTera can assist you if those readings don't match what they should so good laboratory practice is absolutely vital when calibrating a probe you know when you do a full calibration make sure you do so you know in a clean environment use clean solutions they can be stored for up to a month and you can put them into a fridge and chill them that's fine but just allow those solutions to come up to an ambient room temperature because you need to bear in mind that stated accuracy of our probes as with all probes as is sort of an industry standard gobly it's usually quoted at either 20 or 25 degrees if you calibrate that at a lower temperature you are obviously calibrating it that and it will be based from that temperature so all of this is covered in our manuals but it's worth calibrating in an ambient temperature and then allow all of your solutions to warm to that ambient temperature make sure your probe is clean usually with dynamized water to remove any excess chemistry and then you're good to start your calibration so just finally I'm just going to play a video this is just a randomly chosen video these are available on YouTube so I'll allow this video just to play out any questions that get fielded to Richard so have a good day I hope you enjoyed Ryan's presentation just a few takeaways I guess we're a bit short of the time today but I hope you enjoyed that I suppose there are many options right for measuring water quality as I mentioned Ryan's covered spot and continuous monitoring today but remember those sort of satellite options that are emerging as well there are many many ways to integrate data together so you can integrate spot measurements and continuous data together but if you're going to do integration you need to understand your data provenance well so I'm getting out at the other end and I've given you some frameworks from the Bureau of Metrology to have a look at I think when it comes to water quality sensors and some of my learnings you need to choose your sensors carefully particularly think about the environment they're being deployed in we've deployed many water quality sensors over the years and I can remember one site where we had a lot of algae coming out of a wastewater treatment plant and that would coat the sensors within hours of having been cleaned so in the end you needed a really rigorous ongoing maintenance regime so really try and plan and design your system with the deployment environment in mind Ryan was I thought pretty good around calibration and maintenance there's a few learnings for me there in terms of particularly if we're dealing with gaseous samples like you sometimes get with deeper groundwater samples the errors that can occur from those bubbles getting around the sensors so how to avoid that particularly with that sort of low flow sampling example I thought the advice about with data validation and cross checking with lab samples was also a really good point that he raised my take on it is it's quite often difficult to get a really good correlation between lab analysis and a field reading I think field readings are excellent for determining trends but if you're looking for an absolute correlation between what you're seeing in the field and what you're seeing in the lab it can often be difficult to do and that sometimes is associated with the errors that come from actually collecting a sample in the first place for example so you end up with cumulative errors that can lead to discrepancies between those numbers in terms of other things that I heard well what I saw was to actually calibrate things properly you need to have a pretty nice clean area to do it in the back of the it will take a bit more work in terms of achieving that same quality that Ryan had videoed and it also takes time right even with all those efficiencies they've built into their instrumentation it does take time to calibrate instruments properly and you do need to do it regularly otherwise the results you're getting are going to be less than perfect so I would say that I'll answer a couple of questions that are here but instruments are only as good as the calibration and maintenance that you're performing give us a call when you're looking at setting up a water quality monitoring regime whether you're renting the equipment from us or deploying it for long term we can help provide guidance on the design of the monitoring and maintenance regimes to ensure that you're doing appropriate data and it's important that you cost that maintenance into your programs a lot of people get approval to buy all this instrumentation which is obviously great for Hydrotera we're selling lots of equipment but often the operational expense associated with maintaining and calibrating them is forgotten and you've heard some pretty rigorous sort of frequencies that Ryan was throwing around today the frequency of calibrations there is a real cost associated with them what I am seeing I guess in my role as sort of scouting the world for new and emerging sensor technologies is that around pH sensors there are these new sensors emerging which are solid state in nature and do not have the same calibration requirements to be a traditional sort of membrane based pH sensors recently signed up with a couple of companies that have those solid state pH sensors CSIRA is also working on research on pH and multi parameter sensors that can be buried in sediments like in tailings and things like that and I've been lucky enough to be involved in an evaluation panel of that so the world of measurement is always changing and water quality seems to be getting more and more complex as different sorts of sensors are emerging so feel free to give us a call and I'm happy to share my thoughts when you're looking at designing water quality monitoring program now over to questions I only have one question today pretty small number for our webinars Anthony Dixon hi great presentation what is the lowest concentration of ammonia that the sensor can measure well I've got a few different choices for ammonia sensors I think what's best Anthony is if I just email you through the data sheets I'm not sure off the top of my head so I will come back to you I'll just make a note to get in touch with you and give you a call on that one but thanks very much for your question in terms of other questions we appear to have no other questions which is kind of lucky we've only got one minute left on the clock but thank you very much for joining us I hope that you found this informative certainly enjoying presenting to yourself and it was great to have so many people here today enjoy the rest of your day and enjoy the long weekend all right that's it from me thank you very much