Let s take a look several devices and methods for obtaining measurements of water quality in the field.

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1 EHST 2361 Environmental Sampling and Analysis Calibration and Use of Dissolved Oxygen and ph/conductivity Field Meters and Colorimeters in Water Quality Investigations Introduction We are taught that samples are taken and delivered to the analytical laboratory for analysis. In reality, some analytes including several indicators of water quality can be measured in the field. Of these, a few must be measured in the field because it is either easier to do so or the process of sampling and delivery to the laboratory alters the analyte in an unpredictable way. Four water quality parameters typically measured in the field are dissolved oxygen concentration (DO) in mg O 2/l (also called ppm O 2) ph in standard units or s.u. specific conductance (conductivity) in µs/cm or µmhos/cm temperature in F or C To aid the sampling technician, the instrument industry has developed a variety of rugged field meters that provide accurate, defensible results. We rely on these meters and must know how to calibrate and maintain them in order to produce data that meet the needs of our study. Over the last decade devices that, due to their size, power requirements, or complexity, were once only available in the laboratory are now available for use in the field. Once such device is the colorimeter, a portable type of spectrophotometer. Water quality parameters commonly measured in the field using a colorimeter are turbidity in TU or total suspended solids (TSS) in mg/l phosphate or orthophosphate in mg/l ammonia in mg/l nitrate in mg/l Let s take a look several devices and methods for obtaining measurements of water quality in the field. The HACH HQ40d Portable Meter and LDO Dissolved Oxygen/Temperature/% Saturation Probe The DO meter replaces the Winkler Method, a messy wet method (titration) that requires the use of caustics, special glassware, pipets, and burets. This HACH digital meter offers significant advantages over the older, analog meters like the YSI 54A. The primary advantage over the older technology of the YSA 54A is the LDO probe is calibrated much less frequently, as few as one time per year which translates to less preparatory work before use. Another advantage is the meter also accepts ph and conductivity IntelliCAL probes creating a single device that can collect multiple water quality parameters, saving you the effort of carrying several devices to each field site. The LDO probe requires much less maintenance than the YSI DO probe. However, the LDO requires the annual purchase of a probe sensor cap with matching calibration IntelliCAL ibutton at a cost of approximately $150. Annual maintenance cost for an analog meter and probe is literally pennies. Principle of operation: The HACH LDO sensor is coated with a luminescent material. Blue light from an LED is transmitted to the sensor surface. The blue light excites the luminescent material. As the material relaxes, it emits red light. The time from when the blue light was sent and the red light is emitted is measured. The more oxygen that is present the shorter the time it takes for the red light to be emitted. This time is measured and correlated to the oxygen concentration. Between the flashes of blue light a red LED is flashed on the sensor and used as an internal reference. (From the HACH website) Calibration While calibration of the HACH HQ40d Portable Meter and LDO probe need only occur annually, you will perform a calibration as part of today s lab. For most field meters, calibration is essential prior to use. Typical calibration is the process of showing the meter one or more solutions containing a known amount of the analyte (in this case dissolved O 2). This is most often accomplished using specially-prepared standards that are purchased from a reliable source. The

2 probe is placed into the standard and the reading on the meter adjusted to read the value of the standard. The meter then stores the calibration values electronically and is assumed to perform accurately for the period specified by the manufacturer at the end of which another calibration is required. Calibration is performed in the field at the beginning of the day and checked or recalibrated periodically throughout the day. THE DO METER IS CALIBRATED A LITTLE DIFFERENTLY. The particulars of calibrating the DO meter are as follows. The amount of O 2 that can dissolve in a liquid like surface water is a function of field temperature and atmospheric pressure. Therefore both must be known to properly calibrate the meter, that is, to tell the meter how much O 2 to expect to see in the standard. The temperature probe built into the meter is factory calibrated and assumed accurate between periodic factory servicing. This probe will provide the temperature value we need for calibration. The meter also measures the atmospheric pressure needed to complete the calibration. The HACH LDO does not need a standard solution for calibration. Instead the probe is fitted with a small calibration bottle. Once placed on the probe, the calibration bottle creates a water-saturated air environment around the probe that simulates a water sample holding as much O 2 as possible at a given temperature and pressure. After stabilization, the temperature and pressure values are used to compute the standard DO saturation value used to calibrate the meter. This calibration method is called saturated air calibration. Other methods of calibration do exist. Procedure for Calibrating the HACH HQ40d and LDO: 1. LDO Calibration is performed manually using water-saturated air. 2. Locate the calibration bottle and add a small amount (about 1 cm) of water to the bottle, cap, and shake vigorously for several minutes. 3. Press the BLUE/LEFT key under Calibrate. 4. Remove the bottle cap, carefully blot the probe dry, and insert the LDO into the calibration bottle BEING CAREFUL NOT TO TOUCH THE PROBE CAP. 5. Check to make sure there is no water adhering to the probe cap. 6. Press the GREEN/RIGHT key under Read. 7. When the reading is stable the standard value will be highlighted on the screen and the calibrated reading will appear on the screen. 8. Press the UP key under Done. 9. Press the GREEN/RIGHT key under Store to accept the calibration and return to the measurement mode. 10. When calibration is successful, the display will show OK in the upper left hand corner. Additional Considerations: 1. The DO saturation is inversely proportional to temperature. Cold water holds the most O Supersaturation of water can occur when a cold water sample is warmed without agitation or if pure oxygen is bubbled into water. Supersaturation can be detrimental to aquatic life. 3. Low DO is detrimental to aquatic life. Signs of stress are likely to be seen at values below 4 mg O 2/liter. 4. Vigorous agitation while sampling or analyzing water can artificially introduce O 2 and result in higher than actual readings 5. Some gases or dissolved substances may interfere with the workings of the probe. Check the information accompanying the specific unit and probe you plan to use to understand potential interferences. Continued

3 HACH HQ40d Portable Meter and LDO probe Specifications: Dissolved Oxygen Range mg/l 1-200% saturation Dissolved Oxygen Accuracy ±0.1 mg/l for mg/l ±0.2 mg/l for greater than 8.0 mg/l % Saturation 1.0% Temperature Range 0-50 C Temperature Resolution 0.1 C Temperature Accuracy ±0.3 C Analyzing DO in Water: 1. The probe may be placed directly into surface water or collected sample. 2. Place the probe in the sample, no need to swirl. Press the GREEN/RIGHT key under Read. The display will show Stabilizing and a progress bar will fill from 0 to 100% as the probe stabilizes in the sample. When the result has stabilized, the lock icon will appear and the result will be stored automatically in the data log. 3. Record the DO in mg O 2/liter. Record the temperature. 4. When not in use, protect the probe from damage. There are no special storage requirements for the HACH HQ40d and LDO. Laboratory Activity - Learning the Capabilities of the DO Meter: 1. HACH HQ40d and LDO as instructed. 2. Draw a tap water sample into a 400 ml beaker. Allow the sample to equilibrate for a few minutes. 3. Determine the DO and temperature for the tap water. Determine the DO three more times waiting about one minute between each determination. List your results in the table below. HACH HQ40d & LDO Time DO mg O 2/l Temperature 0 min min min min Average Range 4. Compute the average and the range. If precision is defined as the closeness of repeated measurements of the same quantity, how precise is the meter? 5. Check the accuracy of the meter by immersing the probe into the zeroing solution. Does the meter read zero? 6. Rinse the probe in clean water. Measure the DO and temperature of the pond water samples. Record your results below. Try not to vigorously agitate any sample. Next page for data table

4 HACH HQ40d & LDO Pond Water Sample DO mg O 2/l Temperature Cold Room temperature Warm Assuming the DO in each sample started at the same concentration, what effect does temperature have on DO? We will use your results and Microsoft s Excel spreadsheet program to demonstrate the precision of the DO meter and the effect of temperature on dissolved oxygen. Please be ready to present your data. The Hanna HI Portable ph/ec/tds/temperature Meter and Probe The ph of Water The ph of a liquid is defined as the negative log of the hydrogen ion concentration or log [H + ]. In pure water, H + and the hydroxyl anion (OH - ) exist in equilibrium with water molecules (H 2O). The equilibrium equation is H + + OH - H 2O. Theoretically, pure water has a ph of 7, otherwise known as neutral, and the concentration of each ion is the equation is essentially equal. The addition of acidic or alkaline (basic) materials to pure water changes the ph because the concentration of H + in the solution is affected by the addition. Bases add OH - thereby increasing the concentration of hydroxyl anion and decreasing (relatively) the H + concentration. Basic solutions have ph values ranging from 7 to 14. Acids add H + and decrease (relatively) the OH - concentration. Acidic solutions have ph values ranging from 7 to 0. Beyond the underlying chemistry of acids and bases, ph plays an important role in understanding the hazard properties of materials and the environmental effects of hazardous materials releases. Under RCRA, a waste can be considered corrosive if its ph is less than 2.5 and greater than 12.5 causing it to become subject to RCRA hazardous waste regulations. Ecologically speaking, animals and plants are only found in habitats where the ph is moderate. As a general rule, organisms are not found living in waters or soils with ph values less than 4 and more than 11. Most organisms on the planet are not adapted to ph extremes. Releases of corrosive materials will cause damage to the environment if they are not neutralized or otherwise cleaned up. Areas of distressed vegetation, fish kills, bird kills, and injured or debilitated wildlife may be signs of releases. Neutralization involves chemical treatment of acids or bases resulting in more neutral (ph = 7) materials. For example, HCl could be neutralized with the addition of NaOH: HCl + NaOH H 2O + NaCl a very violent reaction. A better neutralizing agent is sodium bicarbonate (NaHCO 3), HCl + NaHCO3 H 2O + NaCl + CO 2, a weaker base that reacts less violently. There are several different types of ph meters available to the technician. Most have digital readout and data logging capabilities; older models may use analog readout (needle and scale). Meters may be benchtop devices, portable devices, or field devices. The HI is an example of a rugged field meter that produces reliable, defensible results. Benchtop and portable meters are not as rugged as field meters. Field meters are almost always weather (or water) resistant (able to withstand rain and splashes), but rarely water proof (able to withstand immersion in water; well, maybe a brief dunking). Meters need a probe or electrode to sense the ph of the sample. The electronics of the meter then interprets the signal from the electrode and provides a display of the ph. The meter also stores calibration information. Electrodes need to

5 be calibrated frequently. For example, daily, twice-daily, and before each use, may be recommended by meter manufacturers or EPA. The meter is calibrated using ph standards, also called standard solutions or ph buffers. A two-point calibration uses two standards: ph 4 and 7 or ph 7 and 10. Which standards you choose depends on the expected ph of the samples you will be analyzing. Try to select standards that bracket the expected ph of the samples you will be analyzing. If acidic samples are expected choose ph 4 and 7, for basic samples choose ph 7 and 10. A few ph meters use a three-point calibration. Once calibrated, meter function should be periodically recalibrated or checked against a single standard (like ph 7) throughout the day. Procedure for Calibrating the ph function of the HI : 1. Inspect the meter for any signs of damage. Check the probe connector and adjust to finger tight. Examine the probe tip. It should be free from any build up or cracks. 2. If necessary, connect the probe (or electrode) to the meter, remove the probe s protective cap, rinse it with distilled water, and place the probe end into distilled water or ph 4 buffer. 3. Turn on the meter by pressing ON. 4. The meter displays the remaining battery percentage every time it is turned on. Low batteries will give erroneous readings, replace if necessary. 5. Allow the probe and meter a short time to stabilize. 6. Of the three standards available, choose two standards that will bracket the sample ph. Unless contaminated in some way, surface water samples will be between ph 6 and 9. Check the expiration date of the standards use only the freshest solutions within their expiration dates. 7. Follow the manufacturer s instructions and perform a two-point calibration (attached). Note the calibration date, time, standards used, and any useful comments about meter function or maintenance performed in the meter s calibration and maintenance logbook or field notebook. 8. The meter is now ready to be used. Protect the probe when not in use by placing it into ph 4 buffer or its protective cap (filled with ph 4 buffer). Leave the meter on or in stand by mode while traveling between sampling sites or recalibrate in the field. Analyzing the ph of Water: 1. The probe may be placed directly into surface water or a collected sample. The stability indicator will appear in the LCD screen. 2. The probe is gently swirled in the sample until the ph stabilizes. If the water is flowing, there is no need for swirling. The stability indicator will disappear. 3. Record the ph in standard units. Record the temperature. 4. Rinse the probe with distilled water between samples. 5. When not in use, rinse the probe in distilled water and place it into ph 4 buffer or its protective cap. Additional Considerations: 1. Since periodic calibration and checking is needed to ensure accuracy, ph buffers, distilled water wash bottles, and lint-less wipes (like Kimwipes) will be required in the field. 2. The ph probe tip is typically made of thin glass and is therefore susceptible to breakage. 3. Our most common use of the ph function is water and wastewater analysis but the probe can also be used with other liquids. Check the manufacturer s specifications for other uses before measuring the ph of liquids other than water. 4. Vigorous agitation of the sample while measuring may alter its ph. 5. Samples with ph outside of the calibration range will not be read accurately. The error is proportional to the distance away from the calibration range. 6. ph buffers have a limited shelf life and are somewhat susceptible to dilution by samples, other buffers, and wash waters. Obtain fresh buffer after a few uses.

6 Electrical Conductance, Specific Conductance, or Conductivity of Water Surface waters and groundwaters are accurately described as water solutions. In reality, pure water does not exist in nature. Even precipitation, i.e., rain, quickly dissolves atmospheric gases, vapors, and particulates. These enter and leave solution with water according to their equilibrium constants, the presence of other solutes and temperature. Some alter the electrical conductance of water. Pure water is a poor conductor of electricity. However, water solutions improve conductance with increasing solute concentration. Conductivity is therefore a measure of the amount of solute in water and reported as µs/cm (microsiemens per centimeter), µmho/cm, or as total dissolved solids (TDS) in ppm. As a general rule, pollutant contamination increases conductivity. It is not unusual to see industrial effluents with conductivities greater than 1,000 or 5,000 µs/cm. For comparison, pure water has conductivity at or near 0 µs/cm, rainwater is typically less than 40 µs/cm, and surface waters in Ohio are usually less than 500 µs/cm. Conductivity is not only another water quality parameter but useful as a tool for delineating effluent mixing zones or purging wells (as discussed in a previous laboratory). High water conductivity values are physiologically challenging to freshwater aquatic organisms. Some species do not possess the ability to adapt to high conductivity and will leave the area or be killed as a result. In this way and others, conductivity can be an indicator of water quality. Like DO and ph meters, conductivity meters are calibrated. The HI uses a one-point calibration. Like DO, the amount of dissolved substances water can hold is dependent on temperature and pressure, with pressure being less important than it is in DO. The conductivity standard 1413 µs/cm is often used for meter calibration. I assume that this value is a compromise between typical values expected in the field and the stability of the chemicals used to make the standard. Note that with all calibrations, samples with values outside the calibration range or far from the calibration point are subject to error. Therefore, other conductivity standards do exist. Procedure for Calibrating the Conductivity Function of the HI : 1. Inspect the meter for any signs of damage. Check the probe connector and adjust to finger tight. Examine the probe tip. It should be free from any build up or cracks. 2. If necessary, connect the probe (or electrode) to the meter, remove the probe s protective cap, rinse it with distilled water, and place the probe end into distilled water or ph 4 buffer. 3. Turn on the meter by pressing ON. 4. The meter displays the remaining battery percentage every time it is turned on. Low batteries will give erroneous readings, replace if necessary. 5. Allow the probe and meter time to stabilize. 6. Check the expiration date of the standard use only the freshest solution. 7. Follow the manufacturer s instructions and perform a one-point calibration (attached). Note the calibration date, time, standard used, and any useful comments about meter function or maintenance performed in the meter s calibration and maintenance logbook or field notebook. 8. The meter is now ready to be used. Protect the probe when not in use by placing it into ph 4 buffer or its protective cap. Leave the meter on or in stand by mode while traveling between sampling sites or recalibrate in the field. Analyzing the Conductivity of Water: 1. The probe may be placed directly into surface water or collected sample. Gently tap probe to ensure no bubbles are present in the electrode. Note: the conductivity electrode is the slit in the plastic housing at the very tip of the combination probe. 2. The probe is held in the sample until the conductivity stabilizes. The stability indicator will appear in the LCD screen 3. Record the conductivity in µs/cm and the temperature ( C). 4. Rinse the probe with distilled water between samples. 5. When not in use, rinse the probe in distilled water and place it into ph 4 buffer or its protective cap.

7 Additional Considerations: 1. Salinity of seawater is related to conductivity but typically measured using a different device and reported using a different unit (ppt or o / oo). 2. Conductivity standards have a limited shelf life and are very susceptible to dilution by samples and wash waters. Dry the probe with a lint free wiper before placing into the standard. 3. Some older conductivity meters cannot be calibrated. Their function can only be checked against standards and the results recorded. These must be calibrated at the factory. Samples will be present in the laboratory so you can try out the meters on the real thing. These meters will be taken into the field on our surface water and sediment sampling trip. Remember the calibration procedures so you can repeat them in the field. Laboratory Activity - Learning the Capabilities of the ph and Conductivity Meter: If there is time, repeat the DO experiment above using the ph and conductivity function of the HI Record your results below. Remember to wait for the stability indicator before taking your reading. Precision Time ph (su) Temperature Conductivity µs/cm 0 min min min min Average ** Range Effect of Temperature Pond Water Sample ph (su) Temperature Conductivity µs/cm Cold Room temperature Warm Can you draw any conclusions about the precision of the ph/conductivity probe? The effect of temperature? We will use your results and Microsoft s Excel spreadsheet program to demonstrate the precision of the ph and Conductivity meter and the effect of temperature on ph and conductivity. **Average the ph values and place the result here. IMPORTANT NOTE FOR THE PREPARATION OF SUMMARY STATISTICS AND REPORTS USING ph DATA: ph values must be converted back to the H + concentration, averaged using a typical method, then converted back to log [H + ] for reporting. Averaging the ph meter results directly, without transformation, results in inaccurate mean and related statistics like standard deviation of the mean.

8 The HACH Company DR/850 Portable Datalogging Colorimeter A colorimeter depends on the reaction of various added reagents and dissolved analytes in samples to affect the absorbance of light passing through a water sample. The absorbance of a particular wavelength of light by the prepared sample is proportional to the concentration of the analyte dissolved in the sample. There are many procedures available for measuring analytes using a colorimeter, some are approved for use by regulatory agencies like EPA and some are not. Unapproved methods should not be used for regulatory compliance work. A sample of surface water is prepared according to a prescribed method. Typical preparations include measuring a volume of sample (10 ml is a common sample volume), adding one or more reagents, mixing, and allowing time for reactions to occur. The sample is either prepared in the colorimeter s supplied glass sample cell or measured into a glass sample cell after preparation in other glassware. The outer walls of the sample cell are then cleaned to remove fingerprints, water, and any other debris that might affect the transmittance of the beam of light and placed into the colorimeter s sample cell compartment. Colorimeters are capable of generating a beam of light of known wavelength. The wavelength chosen is adjusted, as needed, for different analytical methods. Once placed in the sample cell compartment, the beam of light passes through prepared sample in a glass sample cell. In most preparations, the presence of the analyte of interest, now reacted with the reagents added during the preparation step, causes an increase the absorbance of the beam of light by the sample, essentially the same thing as a decrease in the transmittance of the light through the sample. The decrease in transmittance or the increase in absorbance is directly proportional to the presence of the analyte in the sample. The analyte is now quantified! When EPA-approved methods are chosen for preparing the samples, the colorimeter becomes a very sensitive and powerful tool for quickly (usually less than 30 minutes) quantifying a number of water quality parameters and contaminants in water. With the addition of quality control measures which are part of a typical quality assurance program, data generated by the colorimeter are defensible and on par with laboratory data from approved laboratories. The following basic procedures for measuring turbidity, orthophosphate, and ammonia in surface waters using the HACH DR/850 are taken from the Euclid Creek Volunteer Watershed Monitoring Program: Directions for Performing Physical/Chemical Tests written by Dr. Mike Nichols of John Carroll University in Cleveland. They have been modified slightly for use in this laboratory exercise. Turbidity of Surface Water Measurement Using Colorimeter 1. Turn on the colorimeter by pressing the Exit Φ Button. 2. Remove the cover from colorimeter. 3. Obtain the two sample cells marked DI water and TURB/PO 4 sample; the DI water will already have distilled water in it. 4. Wipe the outside of the DI water cell with a lint-less paper towel to remove any fingerprints and water droplets. 5. Place the DI water cell into the hole (sample cell compartment) in the meter and place the cover on top of the sample to block out all of the light. 6. Press PRGM 9 4 ENTER. 7. The meter should show susld at the bottom of the screen. 8. Press ZERO. 9. The meter should read 0 in a couple of seconds. 10. Remove the DI water cell from the meter. 11. Fill the TURB/PO 4 sample cell to the 10 ml mark with stream water, using a plastic pipet if necessary. 12. Wipe the outside of the cell with a lint-less paper towel. 13. Place the TURB/PO 4 sample cell in meter and place cover on top. 14. Press READ. 15. Record the value on the data sheet. 16. Keep the TURB/PO 4 sample cell in the colorimeter. 17. Proceed immediately to the reactive phosphate procedure.

9 Reactive or Mono Phosphate in Surface Water 1. The TURB/PO 4 sample cell should still be in the colorimeter; if its not place it in the colorimeter. 2. Turn the colorimeter on (Exit Φ Button), if it is not still on. 3. Press PRGM 7 9 ENTER; the colorimeter should read P, P 2O 5, or PO 4 at the bottom of the screen (these are the units of measure). 4. Place the cover over the cell. 5. Press ZERO. 6. Remove the cover and TURB/PO 4 sample cell. 7. Remove the TURB/PO 4 sample cell cap and add the contents of 1 foil PhosVer 3 powder packet. 8. Recap the cell and shake vigorously for 30 seconds. Note: not all of the powder will dissolve. 9. Press TIMER and ENTER. 10. The reaction will take 2 minutes and the solution will turn blue if phosphate is present. 11. After the 2 minute period, wipe the outside of the cell with a lint-less paper towel. 12. Place the TURB/PO 4 sample cell in the meter, place the cover on top. 13. Press READ. 14. Record the value and the units of the measurement (listed as either P, P 2O 5, or PO 4 at the bottom of the screen) on the data sheet. 15. Should the reading be underrange - record the value as underrange, not zero. 16. If the reading is overrange - record it as overrange on the data sheet; this sample will need further analysis in the laboratory. Ammonia in Surface Water 1. Remove the cover of the colorimeter. 2. Turn the colorimeter on by pressing the Exit Φ Button. 3. Press PRGM 6 4 ENTER; the colorimeter should show NH 4, NH 3-N, or NH 3 on the bottom of the screen (these are the units of measure). 4. Use two clean sample cells, they are marked NH 4 blank and NH 4 sample. 5. Fill the NH 4 blank cell to the 10 ml mark with distilled water from the squirt bottle. 6. Fill the NH 4 sample cell to the 10 ml mark with stream water, using a plastic pipet if necessary. 7. Add the contents of 1 ammonium salicylate powder packet to each cell. 8. Cap each vial and shake each for 30 seconds. 9. Press TIMER and ENTER. 10. The first reaction will take 3 minutes, all of the solid will dissolve and the solutions will turn yellow. 11. After the 3 minute period has elapsed, add the contents of 1 ammonium cyanurate powder packet to each cell and cap and shake vigorously for 30 seconds. All of the powder will dissolve. 12. Press ENTER. 13. The second reaction will take 15 minutes and the NH 4 sample solution will turn green if ammonia is present. 14. After the 15 minute time period has passed, wipe the outside of both cells with a lint-less paper towel. 15. Place the NH 4 blank cell into the meter, place the cover over it and press ZERO; the colorimeter will now read Remove the NH 4 blank cell and place the NH 4 sample cell into the meter, replace the cover and press READ. 17. Record the value and units of measure (NH 4, NH 3-N, or NH 3) on the data sheet. 18. Should the reading be underrange - record the value as underrange, not zero. 19. If the reading is overrange - record it as overrange on the data sheet; this sample will need further analysis in the laboratory. After You Have Completed All of the Spectrometric Tests 1. Make sure that all of the solutions in the sample cells (except the DI water cell) have been emptied into a waste bottle or down the drain with water. 2. Each cell has been rinsed with 10 ml of distilled water from the squirt bottle. Rinse each cell at least three times. 3. The data sheets are complete. 4. All trash has been placed into a waste plastic bag. 5. The colorimeter is off. 6. All equipment and materials have been placed back into their storage containers.

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13 GENERAL INFORMATION SITE NAME OR NUMBER: STREAM NAME: INVESTIGATOR(S): DATE AND TIME STARTED: Surface Water Quality Monitoring Data Sheet WATERSHED NAME: WEATHER PAST 24 HOURS: HEAVY RAIN STEADY RAIN INTERMITTENT RAIN OVERCAST CLEAR/SUNNY WEATHER NOW: HEAVY RAIN STEADY RAIN INTERMITTENT RAIN OVERCAST CLEAR/SUNNY AIR TEMPERATURE: F OR C STREAM OBSERVATIONS: WATER COLUMN STREAM BOTTOM STREAM BANK FISH PRESENT? YES NO MONITORING DATA WATER TEMPERATURE: F OR C DISSOLVED O2: (MG/L) METHOD/METER USED: CALIBRATION/NOTES PH: (S.U.) CALIBRATION NOTES CONDUCTIVITY: (µs/cm OR µmhos/cm) CALIBRATION/NOTES METHOD/METER USED: STANDARDS USED EXPIRATION DATES METHOD/METER USED: STANDARD(S) USED EXPIRATION DATES TURBIDITY TURBIDITY TUBE: (CM OR IN) RESULTING TSS: (MG TSS/L, FROM TABLE) circle TURBIDITY METER: (MG TSS/L) METER USED: OTHER PARAMETERS ORTHOPHOSPHATE: (MG/L) AMMONIA: (MG/L) CALIBRATION/NOTES OTHER (LIST) STREAM FLOW: (FT 3 /SEC, CFS) METHOD/METER USED: NOTES