Case Studies & Application Stories
TweetThe need for safe drinking water in rural Ghana inspired Katherine Alfredo, a graduate student at the University of Texas at Austin to propose a project for a Fulbright Fellowship. The purpose of the fellowship was to map the extent of the fluoride concentration in the Bongo District of the Upper Eastern Region for use […]
The need for safe drinking water in rural Ghana inspired Katherine Alfredo, a graduate student at the University of Texas at Austin to propose a project for a Fulbright Fellowship. The purpose of the fellowship was to map the extent of the fluoride concentration in the Bongo District of the Upper Eastern Region for use by local authorities and eventually use the data collected in the development of a cost-effective defluoridation filter for existing capped wells.
In rural areas, groundwater is plentiful, but natural geographic contamination by inorganic contaminants like iron, manganese and fluoride render government sponsored boreholes useless. Fluoride in the Upper East, Upper West and Northern regions of Ghana often exceeds the general WHO recommended limit of 1.5 mg/liter.
Katherine began her research by observing and recording local water usage habits. She conducted borehole water usage counts on centrally and non-centrally located borehole sites tracking the quantity of water collected daily. Coupling this data with familial compound water usage surveys she was able to begin understanding the volumetric demand placed on each borehole daily and how that volume translates to the household level.
A one-liter sample of water was retrieved for testing and used for all the water quality tests. An aliquot of the sample water was placed in an Ultrameter II 6P to measure pH, ORP, conductivity, total dissolved solids and temperature.
Conductivity readings from the Ultrameter II will be used to simulate influent water containing excessive levels of fluoride in Katherine’s laboratory. Using Bongo as a design test case, Katherine plans to adjust the ionic strength of her synthetic influent to reflect that seen in the Bongo District.
Ultrameter II TDS readings were used as a quality indicator of water as it was dispensed from a borehole. The amount of all dissolved solids is important in determining the potential for interference and competition for adsorption sites on the aluminum adsorbents. Preventing any ions from competing for active sites on alumina surfaces will greatly increase the efficiency of filtration.
ORP readings taken by the Ultrameter II gave a good indicator of the general biological activity in the water. Additional testing was performed using two 2 mL tubes filled with sample water to measure nitrate/nitrite and ammonia using test strips. In another 2 mL tube a 1:1 dilution of the sample was created using distilled water to measure alkalinity using test strips.
Using a 0.45 micron filter, a 30 mL or 60 mL sterile plastic bottle was completely filled for fluoride concentration testing later in the laboratory.
Each capped borehole, new borehole, or nonfunctional borehole that was visited had its corresponding borehole identity recorded in a handheld GPS device. After each governance was covered, eight capped boreholes were chosen for water quality testing to be compared to the nearby functional boreholes.
At the time of Katherine’s departure, she had reported the pH and fluoride concentration of each well to the two water and sanitation government agencies in the Bongo area—The Community Water and Sanitation Agency and The Bongo District Assembly Water and Sanitation Team.
Katherine continues to analyze data recorded in Ghana and experiment with cost-effective solutions for fluoride removal in rural communities.
Expert Manages Storm Water Discharge in Active Construction Sites With Ultrameter II 6P: MyronLMeters.com
Tweet Mike Alberson, an expert in storm water pollution prevention, uses the Myron L Ultrameter II 6P to meet new and existing state and federal requirements for storm water monitoring. He checks for the presence of pollutants by testing the levels of total dissolved solids (TDS) and conductivity. He also tests storm water pH levels […]
Mike Alberson, an expert in storm water pollution prevention, uses the Myron L Ultrameter II 6P to meet new and existing state and federal requirements for storm water monitoring. He checks for the presence of pollutants by testing the levels of total dissolved solids (TDS) and conductivity. He also tests storm water pH levels in accordance with NPDES guidelines implemented in California in 2010 that mandate pH testing for all Risk Level 2 and 3 sites.
Though TDS and conductivity do not indicate the presence of any specific contaminant, monitoring these parameters is a good way to determine an increase in the concentration of dissolved chemical constituents generally. High conductivity or TDS levels are a red flag to Alberson to investigate potential sources of pollution.
Chemicals used in landscaping, such as herbicides, pesticides and fertilizers, as well as materials such as cement, can all potentially dissolve into storm water runoff. Additionally, acidic or basic pollutants impact the quality of water by altering the pH of the runoff. Monitoring is required because altering the pH alters the types and amounts of all chemical constituents in runoff and, thereby, its toxicity. Changes in pH also impact the ecosystem directly when they exceed the narrow range required by biota to live in the receiving waters. The new California NPDES requirements have set a pH range limit of 6.5 to 8.5 pH Units
The State Water Quality Board’s overall goal in implementing increased monitoring and reporting requirements is to evaluate the effectiveness of Best Management Practices (BMPs) on effluent pollution and the impact that construction activities have on receiving waters. Developers and inspectors like Alberson are continually challenged with preventing potential pollutants from leaving the project sites, and when that happens, they need to remediate any adverse affects on the environment.
As a prerequisite to construction, the Developer of Plan must generate and gain approval of BMPs and Storm Water Pollution Prevention Plans (SWPPPs) which take into account the nature of the project’s building schedule, phasing of the project, building materials, the projected rainfall, the percentage of impervious cover on the project and the impact that potential storm water runoff could have on receiving waters. The plans must also address the required monitoring and critical indicators of specific pollutants projected to discharge from the project site.
The site storm water inspector has to ensure that the necessary BMPs are implemented throughout the length of the project, as defined by the project SWPPP plan, which addresses project-specific site conditions and risk level determinations. Alberson uses the meter frequently on Barnhart Balfour Beatty projects as most fall into a category of Risk Level 2, which now requires pH monitoring along during a rain event of 0.5 in. or more.
New California requirements have required all SWPPP developers and inspectors to be certified by the state since Sept. 2, 2011 via a special course given by designated State Trainers of Record (TOR). Alberson is designated as a TOR and offers California’s new Qualified SWPPP Practitioner and Qualified SWPPP Developers courses.
As a trainer, Alberson passes on knowledge gained from his own experience. Through the years, he has seen inspectors send water samples off to laboratories for analysis, the results of which would not be known for up to two weeks. In addition, the pH of these samples would change in the time it took to get the samples to the labs for analysis. Alberson now trains developers and inspectors to use the Myron L Ultrameter II to immediately measure pH, thereby ensuring storm water runoff on project sites is precisely monitored for potential pollutants in real time.
In his own work as an inspector, Alberson has used the Myron L Ultrameter II to respond to potential pollution issues as they arise. For example, at Barnhart Balfour Beatty’s Otay Ranch Village #6 Elementary School project in Otay Mesa, Calif., he developed a remediation solution that prevented environmental contamination from high pH runoff resulting from a required lime treatment of the campus soil. By performing onsite testing following a rain event, Alberson was able to determine the potential runoff had a pH level of 12.5. He decided to immediately utilize a retention pond with carbon dioxide percolation control techniques. His remediation tactic worked using the meter to continuously monitor the pH until it was at a level acceptable for release into the receiving waters.
Tweet The Ultrameter III 9P Titration Kit allows for fast, accurate alkalinity, hardness & LSI titrations in the field. The Ultrameter III 9P is based on the tried and tested design of the Ultrameter II 6P and measures conductivity, resistivity, TDS, pH, ORP, free chlorine and temperature quickly and accurately. The 9P also features new […]
The Ultrameter III 9P Titration Kit allows for fast, accurate alkalinity, hardness & LSI titrations in the field.
The Ultrameter III 9P is based on the tried and tested design of the Ultrameter II 6P and measures conductivity, resistivity, TDS, pH, ORP, free chlorine and temperature quickly and accurately. The 9P also features new parameters that allow the user to perform titrations in the field. The Ultrameter III 9P has a unique method of performing alkalinity, hardness and LSI titrations that makes field monitoring fast and feasible.
How does it work?
The 9P titrations are based on conductometric titration methods that are possible with the 9P’s advanced conductivity cell and microprocessor based design. Titrations are chemically equivalent to standard methods using colorimetric techniques, but replace color change identification of equivalence points with changes in conductivity, thereby replacing a subjective, qualitative assessment with a quantitative one. This means the instrument determines the equivalence point instead of the user and the method of analyzing the equivalence point is objective, rather than subjective.
What is a conductometric titration?
A conductometric titration is performed just like a colorimetric titration, only the equivalence point is determined by a change in conductivity rather than a change in color. This is based on the fact that changes in ionic concentration that occur as constituents react with reagents change the electrical conductivity of the solution.
A simple example can be given of the titration of a strong acid with a strong base. The acid solution, before the addition of the base, has a very high conductance owing to the concentration and mobility of the small hydrogen ions.
With the addition of the base, the hydroxide reacts with the hydrogen to form water, thus reducing the hydrogen ion concentration and effectively lowering the conductivity of the solution. The conductivity continues to decrease until all the hydrogen ions are consumed in the reaction, but then sharply increases with the next addition of base, which contains highly conductive hydroxide ions. The solution conductivity then continues to increase with each base addition. The equivalence point in this example would be a clearly defined minimum point of lowest conductivity (see Figure 2).
Not all solutions will give a plot with an equivalence point that is as easy to distinguish as the sharp upturn found in a strong acid-base titration, however. The 9P plots several reagent additions beyond any changes in conductivity and matches the derived curve to the behavior of solutions of known concentration.
Is a conductometric titration a standard method?
(Standard method comparison to methods listed in the Standard Methods for the Examination of Water and Wastewater published by the American Public Health Assn., the American WaterWorks Assn. and the Water Environment Assn.)
Myron L’s conductometric titration methods are chemically equivalent to standard methods that use the same procedure, but with pH indicators. That means that they use the same reagents in the same sequence with the same theoretical approach. The difference lies in the 9P’s ability to determine the equivalence point based on numerical data, rather than subjective observation of a color change.
The alkalinity titration is modeled after standard method 2320. The sample is titrated with sulfuric acid and conductivity changes are recorded at each titration point.
The hardness titration is modeled after standard method 2340. To reduce the affects of high alkalinity in the form of bicarbonate, acid is first added to the sample. This shifts the bicarbonate toward carbonic acid, then carbon dioxide (reference the carbonic acid equilibrium), which is gassed off the sample. The sample is buffered above pH 10 (effectively pH 12) by the addition of sodium hydroxide. EDTA reagent is then added incrementally, with conductivity measured after each addition.
The LSI titration uses a simplified version of the thermodynamic equations for the determination of the scaling tendency of water developed in 1936 by Dr. Wilfred Langelier. The user simply titrates for alkalinity and hardness, then measures pH and temperature, and the 9P generates the saturation index value automatically.
Conductometric vs. Colorimetric
The benefits of determining the equivalence points by conductometric titrations are that the user does not have to interpret any results. The 9P does it for you using objective measurements. And the 9P is a faster method. For example, a typical colorimetric titration for hardness can take up to 30 drops of reagent, while the 9P method for the same concentration only requires six to eight drops. Colorimetric distinctions are sometimes hard to make, as well, especially when adding reagents drop by drop while trying to carefully observe the precise point at which the color changes—and that can lead to inaccurate data. This is especially true in colored or turbid solutions.
The conductometric method can also be used with very dilute solutions or for solutions for which there is no suitable indicator. The conductometric titration method gives you empirical results that are calculated for you, eliminating potential sources of error. And the measurements can be stored in memory for later data transfer using the optional U2CI software and bluDock Bluetooth hardware installed on the 9P . This makes data analysis and reporting seamless.
What else can the Ultrameter III 9P do?
Alkalinity, hardness, pH and temperature values used to compute the saturation index of a sample can be manipulated in the LSI Calculator function, allowing you to perform on the spot analysis of water balance scenarios. You can use historical or theoretical data to populate the required values in the calculator.
And the 9P titration kit comes with all required accessories, reagents, and calibration solutions (see Figure 6). Streamline your field testing with an Ultrameter III 9P from MyronLMeters, where you can save 10% when you order online.
Myron L Meters is the premier online retailer of accurate, reliable, and easy-to-use Myron L meters like the Ultrameter III 9P. Save 10% when you order online at MyronLMeters.com. Find out more about the Ultrameter III 9P in our Myron L Meters – Ultrameter III 9P Titration Kit Overview video.
Tweet FDA Warning Are You FDA Compliant? In recent news “A warning letter sent to (a dialysis clinic operator) by the US Food and Drug Administration (FDA)”… “FDA said the company needs to take “prompt action to correct the violations addressed in the letter,” and that failure to comply could lead to more serious regulatory […]
Tweet Ultrapen PT3 ORP tester Though the measurement of free chlorine concentration is often indicated for the disinfection of water and disinfectant byproduct control, there is a better way. Because free chlorine works through oxidation, ORP instrumentation can be used to monitor and control its effectiveness. ORP measures the actual oxidation power of the solution, […]
TweetYears ago, high purity water was used only in limited applications. Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes, and even the final rinse at the local car wash. THE DEIONIZATION PROCESS The vast majority of dissolved […]
Years ago, high purity water was used only in limited applications. Today, deionized (Dl) water has become an essential ingredient in hundreds of applications including: medical, laboratory, pharmaceutical, cosmetics, electronics manufacturing, food processing, plating, countless industrial processes, and even the final rinse at the local car wash.
THE DEIONIZATION PROCESS
The vast majority of dissolved impurities in modern water supplies are ions such as calcium, sodium, chlorides, etc. The deionization process removes ions from water via ion exchange. Positively charged ions (cations) and negatively charged ions (anions) are exchanged for hydrogen (H+) and hydroxyl (OH-) ions, respectively, due to the resin’s greater affinity for other ions. The ion exchange process occurs on the binding sites of the resin beads. Once depleted of exchange capacity, the resin bed is regenerated with concentrated acid and caustic which strips away accumulated ions through physical displacement, leaving hydrogen or hydroxyl ions in their place.
Deionizers exist in four basic forms: disposable cartridges, portable exchange tanks, automatic units, and continuous units. A two-bed system employs separate cation and anion resin beds. Mixed-bed deionizers utilize both resins in the same vessel. The highest quality water is produced by mixed-bed deionizers, while two-bed deionizers have a larger capacity. Continuous deionizers, mainly used in labs for polishing, do not require regeneration.
TESTING Dl WATER QUALITY
Water quality from deionizers varies with the type of resins used, feed water quality, flow, efficiency of regeneration, remaining capacity, etc. Because of these variables, it is critical in many Dl water applications to know the precise quality. Resistivity/ conductivity is the most convenient method for testing Dl water quality. Deionized pure water is a poor electrical conductor, having a resistivity of 18.2 million ohm-cm (18.2 megohm) and conductivity of 0.055 microsiemens. It is the amount of ionized substances (or salts) dissolved in the water which determines water’s ability to conduct electricity. Therefore, resistivity and its inverse, conductivity, are good general purpose quality parameters.
Because temperature dramatically affects the conductivity of water, conductivity measurements are internationally referenced to 25°C to allow for comparisons of different samples. With typical water supplies, temperature changes the conductivity an average of 2%/°C, which is relatively easy to compensate. Deionized water, however, is much more challenging to accurately measure since temperature effects can approach 10%/°C! Accurate automatic temperature compensation, therefore, is the “heart’ of any respectable instrument.
RECOMMENDED MYRON L METERS
Portable instruments are typically used to measure Dl water quality at points of use, pinpoint problems in a Dl system confirm monitor readings, and test the feed water to the system. The handheld Myron L meters have been the first choice of Dl water professionals for many years. For two-bed Dl systems, there are several usable models with displays in either microsiemens or ppm (parts per million) of total dissolved solids. The most versatile instruments for Dl water is the 4P or 6PFCE Ultrameter II™, which can measure both ultrapure mixedbed quality water and unpurified water. It should be noted that once Dl water leaves the piping, its resistivity will drop because the water absorbs dissolved carbon dioxide from the air. Measuring of ultrapure water with a hand-held instrument requires not only the right instrument, but the right technique to obtain accurate, repeatable readings. Myron L meters offer the accuracy and precision necessary for ultrapure water measurements.
Inline Monitor/controllers are generally used in the more demanding Dl water applications. Increased accuracy is realized since the degrading effect of carbon dioxide on high purity water is avoided by use of an in-line sensor (cell). This same degradation of ultrapure water is the reason there are no resistivity calibration standard solutions (as with conductivity instruments). Electronic sensor substitutes are normally used to calibrate resistivity Monitor/controllers.
Myron L Meters carries a variety of inline instruments, including resistivity Monitor/controllers designed specifically for Dl water. Seven resistivity ranges are available to suit any Dl water application: 0-20 megohm, 0-10 megohm, 0-5 megohm, 0-2 megohm, 0-1 megohm, 0-500 kilohm, and 0-200 kilohm. Temperature compensation is automatic and achieved via a dual thermistor circuit. Monitor/controller models contain an internal adjustable set point, piezo alarm connectors and a heavy-duty 10 amp relay circuit which can be used to control an alarm, valves, pump, etc. Available options include 4-20 milliamp output, 3 sensor input, 3 range capability and temperature. Internal electronic sensor substitutes are standard on all Monitor/controllers.
Sensors are available constructed in either 316 stainless steel or titanium. All sensors are provided with a 3/4″ MNPT polypropylene bushing and 10 ft./3 meters of cable. Optional PVDF or stainless steel bushings can be ordered, as well as longer cable lengths up to 100 ft./30 meters.
The following table briefly covers recommended Myron L meters for Dl water applications.
Tweet Reverse Osmosis RO Meter – RO-1: 0-1250 ppm with color band RO Meters The choice of professionals for years, this compact instrument has been designed specifically to demonstrate and test Point of Use (POU) reverse osmosis or distillation systems. By measuring electrical conductivity, it will quickly determine the parts per million/Total Dissolved Solids […]
TweetNeed to know the best meter for your application? Review our Bulletins which explain in clear detail the best model for your needs. If you have more questions, visit our FAQ section or send our Experts a question using the contact form. We’ll respond as quickly as possible! Visit MyronLMeters.com for videos, operations manuals, FAQ, […]
Need to know the best meter for your application? Review our Bulletins which explain in clear detail the best model for your needs. If you have more questions, visit our FAQ section or send our Experts a question using the contact form. We’ll respond as quickly as possible! Visit MyronLMeters.com for videos, operations manuals, FAQ, MSDS, and more information about Myron L meters.
Accurate fountain (dampening) solution concentration control is essential for consistent, high-quality results in lithography. Low concentration can cause drying on the non-image area of the plate resulting in tinting, scumming, blanket piling, etc. High concentrations, on the other hand, bring about over-emulsification of the ink. This results in weakening of color strength and changes in ink rheology (body and flow properties). Correct concentration will allow the non-image areas of the plate to be appropriately wetted.
Ways to Test
Traditionally, pH was the test relied on to determine fountain solution concentration. Today, however, conductivity testing is recognized as a much more accurate method. Many modern dampening solutions are pH stabilized (or buffered), so only small changes in pH are seen even when dramatic changes occur in solution strength. Conductivity measurement is a fast and easy test which is more indicative of fountain solution concentration than pH. This is true for all neutral, alkaline, and many acid type solutions.
pH is still important, however, with unbuffered acid fountain solutions. Checking both conductivity and pH can provide valuable information. Acid fountain solution is a mixture of gum arabic, wetting agents, salts, acids, buffers, etc. Conductivity will tell you if the proper amount of most ingredients are present, but pH is necessary to check acid concentrations. pH will also determine how effective one ingredient, gum arabic, will be.
What is conductivity? Conductivity is the measurement of a solution’s ability to conduct an electrical current. It is usually expressed in microsiemens (micromhos). Absolutely pure water is actually a poor electrical conductor. It is the substances dissolved in water which determine how conductive the solution will be. Therefore, conductivity is an excellent indicator of solution strength. To properly measure the conductivity of fountain solutions:
Test and write down the conductivity of the water used to prepare the solution.
Mix the fountain solution concentrate with the water, using the manufacturer’s recommendations or as experience dictates.
Measure the conductivity of the mixed solution.
Subtract the water conductivity value obtained in step 1. This is necessary because tap water quality can change from day to day.
The resulting number is an accurate indicator of fountain solution strength. Caution: because alcohol will lower a solution’s conductivity, always test solution conductivity before and after the addition of alcohol.
Determining the best concentration of fountain solution is mostly ‘trial and error.’ It can be very useful to make a graph, recording readings for every one-half or one ounce of concentrate added to a gallon of water. Record readings on a graph with the vertical axis representing conductivity values and the horizontal axis representing ounces/gallon. Such a graph will help ‘fine tune’ your system during future press runs.
For ‘on the spot’ fountain solution tests, Myron L meters are fast, accurate, and reliable. Measurements are made in seconds simply by pouring a small sample of solution into the instrument cell cup and pressing a button. Automatic temperature compensated accuracy and reliability have made our instruments popular in pressrooms worldwide.
Even though pH usually is not the best method to check the concentration of fountain solution, it is still very important and must be checked regularly. The pH of acid dampening solution affects sensitivity, plate-life, ink-drying, etc. Also, pH can change during a run if the paper has a high acid or alkaline content. pH, therefore, must be maintained at the proper level for good printing.
A convenient and accurate way to test pH (as well as temperature) is the waterproof ULTRAMETER II Model 6P or TECHPRO II TH1. The 6P has a 100 reading memory and the TH1 has a 20 reading memory to store test results onsite. The 6P also measures conductivity. All electrodes are contained in the cell cup for protection. Model M6/PH also measures pH and conductivity.
For continuous monitoring and/or control of fountain solution concentration, we offer a complete series of in-line conductivity instruments. These economical, accurate, and reliable models use a remotely installed sensor and a panel/wall mount meter enclosure. Most contain an adjustable set point and heavy duty relay circuit which can be used to activate alarms, valves, feed pumps, etc. All models contain a 0-10VDC output for a chart recorder or PLC (SCADA) input, if required, (4-20mA output is also available).
The 750 Series II with dual set point option has become quite popular in pressrooms. The two set points allow a ‘safe zone’ for controlling fountain solution concentration.
Ultrameter II 6P, 512M5 and M6/PH are available with the useful LITHO-KIT. This accessory includes a foam-lined, rugged all-plastic carrying case with calibrating solutions and buffers. In addition, a syringe to simplify drawing samples and a thermometer for testing fountain solution temperature are also included.
Tweet WHY ARE TESTS SO IMPORTANT? Modern growing practices include scientific evaluations of soil, water, fertilizers, diseases, etc. While some tests are best performed by a laboratory, others can be easily conducted on location, saving time and money. Three tests in particular, EC, pH, and ALKALINITY, […]
WHY ARE TESTS SO IMPORTANT?
Modern growing practices include scientific evaluations of soil, water, fertilizers, diseases, etc. While some tests are best performed by a laboratory, others can be easily conducted on location, saving time and money. Three tests in particular, EC, pH, and ALKALINITY, can reveal valuable information about water quality, soil salinity, and fertilizer concentration. Our portable AGRI-METERS™ provide you with a simple, fast, and accurate means of testing these parameters.
WHAT IS ELECTRICAL CONDUCTIVITY (EC)?
EC is the measurement of a solution’s ability to conduct an electrical current. For horticultural applications, the unit of measure is often expressed as millimhos. Absolutely pure water is actually a poor electrical conductor. It is the substances (or electrolytes) dissolved in the water which determine how conductive the solution will be.
Therefore, EC can be an excellent indicator of:
1. Water quality
2. Soil salinity
3. Fertilizer concentration
EC AND WATER QUALITY
The quality of irrigation water is one of the most critical factors influencing your growing operation. It is important to have a complete water analysis performed on a regular basis. Environmental conditions such as drought, changing seasons, heavy rainfall, etc., can cause the concentrations of dissolved salts in your water to vary significantly. These dissolved salts (i.e. calcium, sodium, etc.) can directly affect your plants’ health and, over time, render even the best soil useless.
You can monitor your overall water quality by testing its electrical conductivity with an AGRI-METER™. The higher the EC, the more salts are dissolved in your water. By comparing your EC with previous readings, you can tell if any dramatic changes have occurred. Nutrient deficiencies are possible when water is too pure (low EC) or if the relative concentrations of some nutrients are unbalanced (i.e. calcium/magnesium). On the other hand, nutrient toxicities or osmotic interferences can also be traced to water quality. Water EC of even one millimho or below can cause problems. High EC readings of more than two millimhos can suggest serious problems, and special cultural procedures may be required.
EC AND SOIL SALINITY
“Water, water, everywhere, but not a drop to drink” is an old saying that applies to your plants when the soil salinity becomes too high. Salts from irrigation water and fertilizers tend to accumulate in your soil or growing media. High soil salinity disrupts the normal osmotic balance in plant roots. In severe cases a plant will become dehydrated even when the soil is wet. Symptoms of high soil salinity include: leaf chlorosis and necrosis, leaf drop, root death, nutrient deficiency symptoms, and wilting. All too often these symptoms are not recognized as being caused by soluble salts in the growing media. Sampling your soil and testing the EC of an extract can reveal important information about a soil’s suitability and your crop’s health.
Samples should be representative of different depths and locations. An easy-to-perform extract method is available with a Soil Test Kit. A 2:1 or 5:1 water-to-soil ratio is made using the small vials provided. Soil test labs often use a method that calls for testing the EC of an extract from a thicker slurry. Therefore, you may see higher soil EC readings from a lab. It is important to standardize your sampling, extract, and testing methods. This will keep the difference between lab and field testing to a predictable factor.
EC AND FERTILIZER CONCENTRATION
You know how important fertilizer is to your plants, but do you know how accurate your fertilizer dosage is? Relying on traditional proportional methods is risky to plants and can waste expensive fertilizer. Improperly mixed fertilizer or a malfunctioning injector can lead to less than optimal results or even a disastrous loss of crops. Many fertilizer companies now recommend using a simple EC test to verify correct fertilizer concentrations. Many growers check their fertilizer injectors on a weekly basis, or they use a continuous EC monitor.
Fertilizer companies and suppliers often can provide a chart relating EC to parts per million concentrations of their various fertilizers. If one is not available for the fertilizer you use, carefully make some stock solutions at commonly used strengths and test their EC. This will give you a data base for future reference.
To test the EC of fertilizer solutions:
- Test and record the EC of the water to be mixed with the fertilizer.
- Test the conductivity of the fertilizer and water mixture.
- Subtract the water conductivity determined in #1 above.
- The resulting figure is an accurate indication of how much fertilizer is present (a higher conductivity means more fertilizer).
Important note: Interpretation of results differs from formula to formula and even among manufacturers of the same formula. Obtain the proper EC charts from the fertilizer company.
Myron L Meters sells both portable and inline instrumentation to make your fertilizer monitoring easy. Myron L AGRI-METERS™, AG-5 and AG6/PH, TH1, waterproof TECHPRO II™ models TP1, TPH1 and TH1, and waterproof ULTRAMETER II™ models 4P and 6PFCEare handheld instruments which make fertilizer testing as simple as filling a cup and pushing a button.
The Myron L 750 Series II™ EC Monitor/controllers can be used to continuously monitor your fertilizer concentration. Their “alarm” relay circuit acts as a safeguard in a fertilizer injection system or even as the main controller for your injector. A 0-10 VDC output for chart recorders or PLC (SCADA) input is standard on all monitor/controller models.
IMPORTANCE OF pH
pH, the measure of acidity or basicity, should be included in any soil or water test. It is well documented that growing media pH is critical to successful plant growth. This is especially true for new soilless mixes and hydroponics. pH affects the roots’ ability to absorb many plant nutrients. Examples include iron and manganese, which are insoluble at high pHs and toxic at low pHs. pH also directly affects the health of necessary micro-organisms in soil.
The effectiveness of pesticides and growth regulators can be severely limited by spray water pH that is either too low or too high.
It is important to note that testing the pH of irrigation water reveals only part of the story. Testing water alkalinity (bicarbonates and carbonates) is much more important than generally recognized. Alkalinity dictates how much influence the water’s pH will have on your soil and nutrient availability. In addition, alkalinity has a very great effect on the ease or difficulty of reducing the pH of water.
TweetWhen disaster strikes, people are scared and disorganized. They need resources — safe water and proper sanitation — that aren’t easy to come by in the aftermath. Without the help of humanitarian organizations to provide assistance, large populations of survivors are subject to epidemics of cholera, diarrhea, meningitis, and other diseases as they struggle to […]
When disaster strikes, people are scared and disorganized. They need resources — safe water and proper sanitation — that aren’t easy to come by in the aftermath. Without the help of humanitarian organizations to provide assistance, large populations of survivors are subject to epidemics of cholera, diarrhea, meningitis, and other diseases as they struggle to meet these basic needs.
Dr. Roddy Tempest, a leading designer and manufacturer of water purification systems has headed the efforts of public and private aid organizations, such as the United Nations and AmeriCares, in responding to people in crisis all over the world for over 15 years.
Dr. Tempest contributed his expertise and experience in such situ- ations as the aftermath of Hurricane Andrew in 1992, the Kosovar refugee crisis in the Balkans, the devastating earthquakes in Tur- key and the flood and mudslides that ravaged the coastal states of Venezuela in 1999. He has assisted in disaster relief efforts in Japan, Africa, Central America, and Taiwan, as well.
So when AmeriCares launched its water purification program for the inhabitants of Sri Lanka following the devastation of the tsunami on December 26, 2004, it turned to Dr. Tempest.
For this heroic effort, Dr. Tempest used two Ultrameter II 6P portable, handheld water testing instruments. Dr Tempest said the instruments gave him “a good, quick first-brush assessment of the possible water sources.”
The Ultrameter II reported and recorded instant precise measurements of Conductivity, Resistivity, TDS, ORP (REDOX), pH, and Temperature. But creating a livable situation for hundreds of thousands of displaced survivors wasn’t as easy as testing the water.
Water Doctor to the Rescue
From his offices in the United States, Dr. Tempest responded to the call for help by first reviewing satellite maps that showed the location of potential water sources in relation to groups of survivors, or Internally Displaced Persons (IDPs). He assessed the total situation of the potential water sources, trying at a glance to deter- mine possible contamination by flooding or infiltration of seawater. Upon his arrival in Sri Lanka, Dr. Tempest worked 24 hours a day to determine a suitable survival supply of water for the IDPs. As indicated in the World Health Organization’s Environmental Health in Emergencies and Disasters, the required water per person per day is 15 liters / 3.963 gallons.
Faced with this daunting task, Dr. Tempest surveyed the land via helicopter and fixed wing aircraft to record the extent of the damage, the location of IDPs, and the viability of potential water sources. Some of the photographs reveal the mammoth challenge he had ahead of him. Debris lay everywhere, indicating the likelihood of surface water and well contamination. Filtration was a must.
Dr. Tempest then combined satellite imagery, the photographs and sketches of water sources from his survey and a list of supplies to determine which water sources would be targeted for testing.
Following World Health Organization guidelines, Dr. Tempest considered as many potential water sources as possible, not just the most obvious ones. These included surface and groundwater near the groups of IDPs and tankered or bottled water brought in from a distance – though this would not be suitable for the long- term supply. The preferred source would have been groundwater, especially for the long-term.
Ultrameter II in Action
Dr. Tempest used the Ultrameter II 6P to screen these sources for their potential disinfection and filtering.
First, Dr. Tempest considered whether or not potential water sources could be protected from pollution and secured. Any potential source water had to be filterable and sanitizable. If the water was brackish, it would require a certain treatment method. If it was high in turbidity, then it would require another. If the pH needed adjusting, then yet another. If the source water was not easily treatable, then the source had to be discarded as an option and a better alternative found.
The Ultrameter II provided Dr. Tempest with fast, reliable, accurate initial information on whether or not to pursue further testing and treatment of a potential source. Dr. Tempest used a multiparameter approach and tested for Total Dissolved Solids (TDS), pH, ORP (REDOX), and temperature (recorded with every reading taken.) He also tested for turbidity and bacteria using other instrumentation.
Initially, Dr. Tempest used a measurement of the mineral salt concentration using TDS calibrated to a sodium chloride solution and TDS calibrated to a natural water standard.
Right away Dr. Tempest knew whether or not the water was too saline or saturated to be filtered economically. If the TDS is too high, filtration systems that work by reverse osmosis can be overwhelmingly expensive to operate in a disaster area, especially considering electrical costs alone. At the very least, the systems become less efficient as the TDS increases and a burden in operation and maintenance costs. This is critical for the short-term disaster response, where Dr. Tempest has to get as much safe water to IDPs in as short amount of time as possible.
High TDS can also indicate an unacceptable level of specifically known inorganic contaminants caused by industrial pollution.
And though it is not a health consideration, high TDS water often has an unpleasant taste that deters people from using it. People may try to return to old wells or other sources of previously safe drinking water that have been contaminated in the disaster. The old source may be more trusted than one that tastes “polluted.” So even though TDS is a secondary water quality standard, it can profoundly impact whether or not the new source is acceptable.
Dr. Tempest also took instant electronic pH readings using the Ultrameter II. The pH directly affects the potential to disinfect the water. pH levels beyond 8 will require substantial increases in the amount of disinfectant required or the length of time the water must be disinfected before safe consumption. And at a pH beyond 9, a residual disinfectant is extremely difficult to maintain.
pH is also critical in the long-term disaster recovery planning. pH that is too low or too high affects water balance, as well, and can contribute to either corrosion or scaling of filtration and disinfection system components and plumbing. An electronic meter is the best choice in this application as compared to colored strips or solutions or other colorimetric methods that do not produce the accuracy required to consistently and correctly balance water and maintain proper disinfection levels. The more precisely the pH is maintained, the less costly safe water production is.
Dr. Tempest also took quick ORP (REDOX) measurements using the Ultrameter II. ORP (REDOX) is the oxidation reduction potential of the water and indicates the state of the water for gaining or losing electrons. Unlike pH, which measures the water’s ability to donate or receive hydrogen ions, ORP (REDOX) values reflect the presence of all oxidizing and reducing agents — not just acids and bases. Initially, the ORP (REDOX) value gave Dr. Tempest a rough idea of the organic load in the water. A reading of 650 mV or greater indicated good water quality that could effectively be sanitized by a minimal amount of free chlorine. A value like 250 mV indicated that the organic contaminants would significantly increase chlorine demand and thereby significantly increase operation and management costs.
ORP (REDOX) is not only a good first indicator about the viability of a water source, but it also is the best way of measuring the disinfectant present in the water after treatment has begun.
Putting It All Together
Using all of the results from these parameters and based on his knowledge of the location of IDPs in relation to potential water sources, Dr. Tempest decided which source would satisfy the needs of each specific location of groups of IDPs. Where possible, water treatment technology would be designed around the quality of the source waters tested where IDPs had gathered, since it was not practical to re-locate large groups of people to distant water sources. Unfortunately, in the case of the Tsunami in Sri Lanka, oftentimes the water closest to IDPs could not be filtered and relocation was necessary.
Dr. Tempest found after his first quick assessment of potential water sources that it was not practical to supply the IDPs in parts of the Batticoloa and Ampara Districts along the eastern coast, because the source water was too saline from seawater intrusion. With limited electricity, this
made the use of reverse osmosis or desalination equipment impractical.
He ended up settling on sites that were more inland, using source waters from man-made reservoirs. IDPs were then settled inland near the cleaner water source.
However, the water in the man-made reservoirs was heavily contaminated with toxic blue-green algae.
Dr. Tempest chose microfiltration and ultrafiltration water treatment systems in the eastern district locations, taking algae-infested water over the salt-saturated, so that treatment and operation costs would be significantly less. Dr. Tempest designed, built and commissioned 4 large transportable water treatment systems, each capable of producing over 500,000 liters/day.
Plans then continued to follow through with long-term water treatment using the Tempest Environmental Systems equipment for the Sri Lankan Ministry of Urban Development and Water Supply and their National Water Supply & Drain- age Board (NWSDB). The NWSDB has 14 Ultrameter II 6Ps in current use in Sri Lanka, which are providing continuing confidence checks to ensure system equipment remains up and running properly.
The Ultrameter II 6P is an excellent multiparameter water quality meter used by thousands of water treatment professionals. The instrument can test for pH, total dissolved solids, conductivity, resistivity, oxidation reduction potential, temperature, and has the capability of testing for free chlorine. This meter handles the job of SIX single parameter testers using one single water sample. Save 10% on the Ultrameter II 6P at MyronLMeters.com.