 Well, nice to see you here. As Brenda mentioned, my name is Beverly and I am a PSD student in MDSU. And today we'll be talking about chloride because it's an important micronutrients as Chantal explained before. So let's start with that. So chloride, as we know now, is a micronutrient involved in physiological functions for living organisms like plants, animals, and of course, humans. So it's very important to know how to measure it as well because it's regulated by the EPA. So in North Dakota, we have a specific source of chloride and it's a deposition of salts by prehistoric seaways in the midways area. And it's really cool because right now we have all these formation that have a lot of resources for us like oil, gas, and of course, salts. So when you are talking about chloride in the soil, we need to think that the chloride is originated in the rock that is moving at some point to the soil. So to allow that movement to chloride from the rock to the soil, we have two principle mechanisms. The first one is the capillary water that it's this movement here that basically occur. For example, when you have a straw inside a water glass, you see that the level of the water in the straw is the same that is in the glass. So basically the force that is moving the water inside the straw is the same mechanism that works here moving the water from the ground water to the surface of the soil with chloride and other nutrients dissolved in it. We have a second mechanism to move that water and is the artesian wells. And this is very interesting because it's basically like a bowl. You have a bowl and you feel that bowl with diaphragm and material like, I don't know, maybe it's sand, clay and organic and material. And when, if you create a hole in the center and you add water in one corner, you will see how the hole start and feeling up with water because the preacher of the water that is going inside by this corner is creating a preacher in the middle or in the lowest part of the landscape or maybe in the fracture part of the landscape that allow the water move through the soil profile to reach the surface. And this is so good. Why? Well, because thanks of that we have enough chloride in our soils to supply the plants that we grow. So this is something and very common in the east part, no, in the west part of the, no, in the east part. Yeah. In the east part of the state where we can see thanks to egg bites because of this great information. And we can see that we have enough chloride in the west part of the, in the east part of the state but a little lower in the, in the west part. And this is very interesting because actually in the west part of the state what we have is the oil and gas structure. And this is one of the way that we can move chloride from the ground water to the surface. And this is not so good. Why? Because if we evaluate the, okay, this is the way that we move the, the brine water. Let's, let's go back. Okay, we have the brine water, we extract the brine water together with the oil and gas during the destruction procedure. And after that, if we manage everything okay we don't have any problem. But if we have some spiel like accidental spiel based on the truck or from the tank or from the pipelines we will have a serious problem. Why? Well, because if we evaluate the concentration of chloride in the brine water in North Dakota and other states around USA we are number four in chloride concentration and that is pretty high. It's pretty high because for the EPA the limit is 250 and we are over that number. And here the information is described by counties. And if you evaluate all North Dakota I am not including the rest of the counties because it's not necessary here but we can see that the highest chloride concentration is in the brine water from this part. So that means that when we have a brine spiel here it's a serious environmental situation. So if you evaluate the ions and cations that you have in that brine water you will see that the predominant cation is sodium and the predominant anion is chloride. So that means that the principle salt that we have in this brine water is sodium chloride. And that is something to think about because the sodium chloride is detrimental not just for the soil but also for the organins that live there like plants as we know but also for the airworms because these animals as you know create pores in the soil at organic matter but they are affected by the salt. They reduce in size and reduce in survival as well as some fungi that are very important for the nutrient cycling in the soil. So what happened with the chloride? Well, the chloride goes basically to the wetlands and ground water because the chloride has a negative charge and the soil has a negative charge. And when you have to negative charge you will have, you will see reveal between them. So that means that we will have this SNRI in the future. And that is scenario, let me explain you that when we have a lot of water like in Puerto Rico like Costa Rica, you will see the movement of that water directly to the ground water because you have water to move the chloride that is not attached to the soil because it's negative moving deeper. But the situation is that here in North Dakota when we live, we have a semi-arid climate and that is a variable that we need to consider during our research because the situation is that the chloride movement is not a lot. We don't have enough water to move to move that chloride to the ground water. So the chloride is staying into the soil and affecting the crops. So what we want to discuss today is how we are going to measure that chloride. Why? Because usually when we have that situation with the chloride we send the sample to the laboratory and the sample send us and the laboratory send us the result but we never ask about the method that they use. And that is something very important because actually they have, some of them have advantage that is really important that we know for future decision-making. So let's start talking about the chloride extraction because you have the soil and in the soil you have a lot of things. You have organic matter, you have water, you have air and you have nutrients but the chloride is negative. You don't need to go as much chemical procedure to extract it. You can do the extraction just with water. So basically some of the standard method that we have to make the chloride extraction is the soil-saturated paste and the soil-water solution. And if you work in the North Dakota Department of Environmental Quality you know very well the soil-water solution because they use a radio of one to 20 to evaluate the brine spill and the monitoring. So once you have the chloride extraction you can perform as a chloride quantification and here we have a lot of method that you can see. We have field screening method that maybe is the most common method that we know. We have laboratory method and we have the analytical method. So for today we are going to discuss five of them, this one, this one, this one and this ones because of the mechanics that they use to measure chloride. So let's start with our favorite, the test strips. And why? Well, because in the test strip you have two versions. You have the first one that is for low-chloric concentration and the other one that is for high-chloric concentration. And it's pretty easy to use because you only need to put the water in a plastic cup or something like that and you put the water, you put the soil and after that in the water you measure the chloride by introducing the strip. And when you get the color change in the line from yellow to black that means that you have your end point. So that means that you are not going to measure more chloride because actually it is done. So after that you can measure the chloride concentration basically on the peak that you will see. And it's very interesting the test strip. We will talk more about that in the future and the other option that we have that for this you need to be in a laboratory with all your chemicals and your instrumentation is the volumetric approach. And basically this is a chemical concentration where you have a chloride strip and basically you add a chemical of a known concentration and a indicator. And basically when you reach the concentration of when you reach the same concentration in the treatment and in the chloride you will see a color change in the solution and that color change is the same of here is your end point. So that is a indirect way to measure the chloride concentration. And basically the chemical reaction is here. And another laboratory method that is pretty popular is the Potentiometric Treatation and it's very interesting because here you have like two techniques in one because you have treatation inside this instrument that is connected to a computer and to a pH sensor because in this technique you measure the chloride concentration based on the pH of the solution. How? Well, basically you have the instrument you have your chloride extract you put your sample inside the instrument and the instrument is go to add treatant solution and measure the pH at the same time. And when you see no, when you don't see any change in the pH that means that you reach your end point and your end point is in the middle. And that point will give you the concentration of chloride because that means that here you have low treatant concentration and here you have too much treatant. So here you need to add more and here you added too much. So your middle point is here that is your end point. The other method that we have and to be honest, my favorite is the analytical method. Well, these here basically use a ion chromatographer that is an instrument that has a auto sample and is helped by a pump to pass the sample through the machine specifically to the column that has like micro bits of different materials depending on what you want to do that will separate the anions in the solution and will give you the concentration based on the time that they take to run all the column. And this methodology, it's very interesting because the ion chromatographer is not just for chloride. You can change the column and meet your anions and that kind of things, inclusive proteins. But the situation is that if you see here, this is 14 minutes. So that means that every sample is going to take up to 20 minutes to be evaluated and that is a lot of time and money in a lab. So for chloride here in the ion chromatographic, we are here. So actually for chloride, if you are looking just chloride and you don't want to think about the older situation, you can cut the time of the machine until maybe seven methods or something like that. But the situation is that the column need time to get clean because you need to clean the column because pass the older sample and that take time because you need time to clean the area. So the other method that we are using is the ICP. And this instrument, to be honest, is expensive, but it's present a lot of advantage. Why? Because basically this is a direct method to measure chloride and how it works. Let me explain you. Okay, basically you have your sample, you have a pump that is helping you to move the sample to the instrument. And here you have a in-production of argon air that is going to help through the nebulizer converting the sample into a spray. And that spray will pass through this channel and it will be destroyed by the plasma, by the torch. And that torch, that destruction of the sample by the torch will generate a light that is rated by the instrument because the light can be divided in colors. And if you know, every element has like a specific color. So depending of the color that the machine is getting and the intensity of that color, the machine is determining the concentration of chloride and other elements. And this instrument is really interesting because it's not just for chloride and you can measure a lot of elements at the same time and not just ions, also cations. So when we try to think like, hey, we have a lot of method to measure chloride so which one is correct? Okay, good news. All of them are correct. All of them are good. The situation is that when we use the, for example, test strip to measure very low chloride concentration, that is not working. That is not working. If you need to test your soil for chloride to see if you reach the correct concentration for your crop, send your sample to a laboratory because the test strip is not going to help you to make any decision. So in that case, it's better the chemical filtration, the potentiometric filtration, the IZ or the IZP. But when we are working with Brian's bill, the story is in order. You have very good relationship between the test strip and the older method. And that is something so good because when we have a Brian's bill, we want to act as fast as we can. So this is a great method to say, like, hey, we have a chloride problem here, we need to move forward. So the most important relevance of this presentation is that we need to remember that chloride is not our enemy. Chloride is a micronutrient that we need, that plants need, that animals need. So it's very important to take care of it. And if you are going to analyze the chloride in your soil or in your water, it's important to know that every test method is going to give you a different number. But that do not means that the number cannot be correlated with other methods, like for example, if you are using a chemical filtration, maybe you have a different number if compared with the ICP, but that do not means that the number is wrong, okay? It's just basic on the technique. So for the test strip, it's very important to have in mind that the higher concentration, the better results. And for the ICP, that if you are looking for chloride and you are interested in other elements, ICP is the best option because that will save you money, time and sample because you only need to use one sample for the anions and for the cations. In the ICP, in the IC, you need to use different samples. One for the anions, you need to change the column and after that use a second sample to measure the cations. So it's more complicated. So here is the reference and the contact information if you have any question. So yeah, basically, well the question is that if the quantum test strip, these little babies, yes, they are really, they are a really fast method to determine the chloride concentration, but this is a semi-quantitative. It's like, if you are going to EPA, you cannot go with this result. You need a laboratory, a certified laboratory result. So this is a good alternative to let us know like, hey, we have a chloride problem here, but it's not for like determining if the soil having not for the crops. Okay, do you have a question you say? I did. What, if you sent a soil sample into a lab in North Dakota, what method would they use? Okay, well, for example, eggbys. I am really in love with eggbys because at the final of the year, all the team prepared this really cool report and it's really good because here you have information not just about the nitrogen in the state, but also about chloride and all the cations and annuals in the soil. So for example, they use the potentiometric method that is this one that we have here, but that may vary because that depends of the resource of the laboratory, the place that they are, because for example, if this facility is so big, they can put an ICP, but the situation is that if you have a small laboratory, the ICP baby is not the best option for you because you need tanks of argon and that is a big piece and you need space to build that, you need safety, you need standard procedure. It's not just like buy the instrument and put that in your room and turn on when you need it. Okay, any more questions? Yeah? The ICP? All of them, all of them, yeah. Not all the anions, not all the anions. Oh, well, depending on the calibration of the calibration that you have, if you have your standards and that is the, that is the element that you can be sure, that depends on the calibration that you are using and the calibration standard solution. So for example, if you are using the ICP to measure really low concentration, maybe your standard will have very low concentrations and very specific elements, but that calibration curve is not going to work, for example, with brine spills. So the results depends of the calibration and the calibration standard solution that you are using for. Do you want to add something more? So the ICP, the mine is everything. So if you ran phosphate, this is cool that it was. It's okay. If it isn't going to find the anion fuel for, it's going to find heat, or salt. So that's the difference between the ion of anograph that separates outside anion and different things for each one of them. Whereas the ICP, if ionized with the sample, can get different elements. So these compounds don't work very well. The actual elements, you can hear it out of cable when it's pretty low. Yes, because we need to remember that in the ICP, you don't have the destruction of the sample. So actually the ion, the cation or anion is dissolved in the sample. So you don't need to destroy the sample in order to analyze. But the situation is that in the ICP, you need to destroy the sample with the plasma in order to analyze the like emitted. And during this process is where you are destroying the phosphate. So at the final, you will analyze all the elements, but just the total element, not the anion, the total element.