3. Collecting the Water Sample

A few yards away (preferably downstream or down current) from your exact sampling site, rinse the plastic bucket three times with the water to be sampled. Now go over to your site, lower the bucket gently into the water, and fill it to a level about 2 inches from the lip of the bucket. If the water at your site is more than an arm's length away, your bucket should have a rope tied to the handle. After securing the other end of the rope to something solid, fill the bucket by turning it upside down and dropping it straight down into the water. This will help avoid the futility of having the empty bucket floating all over the surface and refusing to fill. If you are working in very shallow water, do not disturb the bottom while collecting the sample.

Be careful not to artificially increase the dissolved oxygen content of the water you're sampling. This can happen if you splash the water around too much before you sample it - that's why you should rinse your bucket a few yards away from your sampling site. Once you've got the sample, handle it gently. Avoid jostling the bucket or sloshing the water around.

4. Testing Procedures

Apparent Color

1. Compare the color of the water in your sampling bucket with the BCS numbers in the Borger Color System booklet (if deciding on one BCS number is too difficult, you may use up to 2 BCS numbers to describe apparent color).
2. Record a one or two word description of the apparent color of your sample as well as the corresponding BCS number on your data sheet.
3. Rinse a Turbidity Column three times with sample water then fill it to the 50ml line and again compare and record its apparent color and corresponding BCS number.

Turbidity (Clarity)

In water deeper than 3 meters you will test for turbidity using two methods. First use a Secchi disk to test both overall water depth and water clarity or turbidity.

1. Attach the end of the Secchi disk line to a stationary object and slowly lower the disk into the water until you feel it touch bottom.
2. Note where the line breaks the surface of the water. Slowly pull the line in, and as you do so keep one hand on the spot where it broke the water’s surface.
3. The Secchi disk line is marked in red at every meter and in black at the half meter, yellow tape marks every five meters. Count the marks from the waterline to the Secchi disk and record this to the nearest ½ meter as the bottom depth on your data sheet.
4. Slowly lower the disk into the water again until it disappears from sight.
5. Carefully raise the disk until you can just make it out in the water.
6. Note where the line breaks the water’s surface. Again, pull it in and count the marks to determine and record the Secchi depth of the water to the nearest ½ meter. (If you can see the disk when it is on the bottom your bottom depth and Secchi depth are the same).

In the case of shallow water sampling stations (less than 3 meters in depth) you will use only the second method for determining turbidity.

1. Use the Turbidity Column you have previously filled to the 50 ml line with sample water for the apparent color test. Stir the sample with the glass stirring rod in order to distribute turbidity particles. Look vertically through the tube. If the black dot on the bottom of the tube is not visible when looking through the column of liquid, pour out a sufficient amount of the test sample so that the tube is filled to the 25 ml line. If you still cannot see the dot, record the turbidity as "greater than (>) 200 JTU," otherwise, go to step 2.
2. Fill the second Turbidity Column with an amount of distilled water equal to the amount of sample being measured (e.g. 50 ml or 25 ml). This is the "clear water" tube.
3. Place the tubes side-by-side, and note the difference in clarity between the two. If the black dot is equally clear in both tubes, then the turbidity of the sample water is zero. If the water in the sample tube is less clear, go to step 4.
4. Shake the Standard Turbidity Reagent bottle vigorously. Add 0.5 ml to the clear water tube. Stir contents in both tubes to again distribute turbid particles. Check the amount of turbidity by looking down through the solution at the black dot. If the turbidity of the sample remains greater than the clear water tube, continue to add Standard Turbidity Reagent in 0.5 ml increments, stirring after each addition until the turbidity in each tube appears equal. Record the total amount of Standard Turbidity Reagent added.
5. Each 0.5 ml addition to the 50 ml size is equal to 5 Jackson Turbidity Units (JTUs). If a 25 ml sample is used, each 0.5 ml addition of Standard Turbidity Reagent is equal to 10 JTUs. Use the table below to record the turbidity reading in JTU’s on your data sheet. Rinse each tube carefully after each measurement.
6. It is also important to record the temperature of the water at the time of the turbidity reading following the instructions below.

Water Temperature

1. The water thermometer should be submerged in your 2 ½ gallon sample bucket for at least 1 ½ minutes prior to measurement.
2. Locate the bucket away from direct sunlight or wind (on particularly cold days, try to minimize the time the bucket is exposed to ambient air, because the cold air temperature may skew your water temperature reading).
3. Remember to hold the thermometer on the end that is opposite the bulb! Keep the tip of the thermometer submerged (do not lift thermometer from water to read!). Read the temperature while looking at the thermometer perpendicular to the stem.
4. Record the temperature to the nearest 0.5°C.

pH

1. Rinse two (2) small test tubes with sample water three times. Fill each tube to the 5ml line with sample water.
2. While holding the dropper vertically, add ten (10) drops of indicator solution (green, Wide Range Indicator Solution) to each test tube.
3. Cap, invert and shake each tube several times to mix.
4. Remove the caps and insert each tube into the Octet Comparator (Black Box) and match sample color to appropriate color standard. HINT: Hold the comparator up so that light enters through the special light-diffusing screen in the back, but avoid viewing the comparator against direct sunlight or an irregularly lighted background.
5. Read pH measurement to the nearest 0.5 value, compare both tubes for consistency, and take the average of the two measurements and record it as the final pH measurement. If there is a significant difference between the two measurements (i.e. 1.0 pH unit difference), then make a note and repeat the test.

Salinity

1. Rinse the 650 ml clear plastic hydrometer cylinder three times by pouring small amounts of water from the sample bucket. Then, fill the hydrometer cylinder to within 2 inches of the top with water poured from the bucket.
2. Hang the water thermometer in the cylinder so that it is totally immersed, and readable through the side of the cylinder.
3. Carefully remove the hydrometer from its padded case and insert it into the cylinder, until it begins to float then give it a slight twist to remove bubbles. Take care that the hydrometer does not hit the bottom hard (it might break), and that drops of water do not splash on to the hydrometer stem above water level. Allow the hydrometer to float freely. (If the hydrometer is resting on the bottom of the cylinder you need more water.)

 



4. Wait until 3 minutes have gone by since Step 2. Read the temperature of the water in the cylinder to the nearest 0.5°C and record it on your data sheet in the space below the specific gravity reading.
5. Read the specific gravity from the scale on the hydrometer stem to the nearest 0.0005 and record it on your data sheet. Be sure to take the reading:

• Without touching the hydrometer.

• With your eyes at the same level as the water surface in the hydrometer cylinder (viewing the scale up or down at an angle can give an incorrect reading).

• At the point where the flat water surface would cross the hydrometer stem. You will notice that the water curves up slightly next to the wall of the stem (the curve is a meniscus, and it is the same effect witnessed during the dissolved oxygen test). Make sure you measure your result from the bottom of the curve, not the top.

1. Re-check the water temperature reading you recorded earlier.
2. Use the hydrometer conversion chart (Appendix J) to convert your specific gravity reading to salinity in parts per thousand. Run horizontally across the table until you find the column for the temperature at which you took the reading. Then run down the column until you get to the row for the specific gravity you recorded. If the temperature at which you read the specific gravity falls between two of those listed in the table, split the difference, always rounding to the even number.

Hanna Meter

1. Record the number written on your meter.
2. Fill the black compartment at the base of the Hanna meter with distilled water and let it stand for five (5) minutes to allow any dissolved salts on the electrodes to dissipate and to pre-soak the electrodes. (You may have completed this step earlier – if so you do not need to repeat it).
3. Carefully flush out the black base compartment three (3) times with sample water. Do not immerse the meter above the maximum level indicated by a line on the base of the meter.
4. Fill the black base compartment with sample water, let it stabilize for 15 seconds, then record the initial Temperature.
5. Press the meter's Range Switch, wait 15 seconds, then record three (3) sequential readings for Conductivity at 15 second intervals.
6. Press the Range Switch again and wait 15 seconds. Record three (3) sequential pH readings at 15 second intervals.
7. Press Range Switch once more and wait 15 seconds. Record three (3) sequential Oxidation Reduction Potential (ORP) readings at 15 second intervals
8. Press the Range Switch and wait 15 seconds. Record the final Temperature reading.
9. Calculate an average for each parameter (i.e. add all readings for each parameter and divide by the total number of readings for that parameter) and record each parameter's average on your data sheet.

Dissolved Oxygen (DO)

When you begin the fixing process for DO (steps 1-9) start by recording the time and the current temperature of the water in your sample bucket in case it has changed since you first recorded it. As you work through the DO testing procedure, you'll notice the emphasis to avoid trapping any air bubbles in the sample or splashing it around too much. The point is to avoid changing the amount of oxygen dissolved in the water by contact with the oxygen in the air.

To assure more precise dissolved oxygen measurement, three 60 ml samples will be prepared for titration. You will begin by titrating a 20 ml portion of each of these samples. If the results from all three titrations fall within a range of less than 0.6 mg/l you will average these results and report this as your DO average. If the difference between any two titrations is 0.6 mg/l or greater, titrate another 20 ml portion of the 60 ml sample which reads outside of the range. If the result is still different from one or both of your other samples by 6 mg/l or more then average only the two closer readings and record this number as your DO average. If no two of your three original readings fall within a 0.6 mg/l range you will have to repeat the titration process on three new 20 ml portions of each 60 ml sample. Record the results of all titrations (even those you suspect are in error) and average only those which fall within the 0.6 mg/l range.

1. Mark the labels of three 60ml sample bottles with your site number and the letters "A", "B" and "C".
2. Rinse each bottle with small amounts of water from the bucket three times. Rinse the outsides of the bottles and the caps as well.
3. Tightly cap the mouth of the bottle marked "A". Holding the bottle sideways, submerge it to mid-depth in the sample bucket, and remove the cap to allow the bottle to fill.
4. Turn the submerged bottle slowly to a vertical position (mouth up) and tap the sides with the cap to dislodge any air bubbles clinging to the inside. Replace the cap while the bottle is still submerged.
5. Retrieve the bottle and examine it carefully to make sure that no air bubbles are trapped inside. Once a satisfactory (i.e. bubbleless) sample has been collected, repeat Steps 2 through 4 with bottles "B" and "C".
6. Uncap all three samples. Add 8 drops of manganous sulfate solution (pink reagent) to each sample.
7. Add 8 drops of alkaline potassium iodide azide (clear reagent) to each sample. Be sure to add the manganous sulfate first. Drop the solutions in gently to avoid splashing and mixing in air. Hold the reagent bottles vertically, and do not allow the dropper tips to touch the sample.
8. Cap each sample bottle carefully and mix by repeatedly tipping capped bottle back and forth in a gentle rocking motion for fifteen seconds. A fluffy, white to brownish precipitate will form. Set the bottles in their holes in the LaMotte monitoring kit; the styrofoam will help keep the samples at a constant temperature. Allow the precipitate to settle a third of the way down the bottles (past the neck and down to the shoulder of the bottle), so that it fills only the bottom two-thirds. Settling may take as long as an hour at cooler temperatures, but it will usually be faster.

 



After the samples have been gently mixed and allowed to settle, return to the DO procedure at this point:

9. Add 8 drops of sulfuric acid (clear solution) to the first sample bottle marked "A." Cap the bottle and mix by tipping gently as before until the precipitate has dissolved. Depending on the oxygen content of the sample, a clear yellow to brown-orange color will develop as the precipitate dissolves.

 



10. Rinse the titration vial (it is labeled "Code 0299" and has a flat lid with hole in the center) with a small amount of the solution from the sample bottle, then fill it to the 20-ml line. (You'll notice that the upper surface of the solution in the cylinder may curve up or down slightly; this curving upper surface is known as the meniscus. It's the bottom of the curve that should be level with the 20-ml mark, not the portion near the walls of the cylinder).
11. Depress the plunger of the direct-reading titrator (the small syringe) to expel air. Holding the plunger tightly down, insert the titrator into the plastic fitting of the bottle of sodium thiosulfate (titrator) solution. (This bottle is slightly larger than the others and does not have a dropper tip. The sodium thiosulfate solution is colorless.) Invert the bottle and withdraw the plunger slowly until the bottom of the plunger is about half an inch past the zero mark on the titrator scale.

As you start to withdraw the plunger, inspect the solution filling the syringe for air bubbles, especially at the tip of the plunger or in a silvery rim around the tip. If bubbles appear while you've only got a small amount of solution in the titrator, pump the solution back into the thiosulfate bottle, pressing the plunger down quickly and firmly. Bubbles tend to be a particular problem when the dry titrator is filled for the first titration of the day. It may be necessary to pump the solution back and forth several times to get the plunger surface wetted.

Once you've gotten a small amount of sodium thiosulfate solution into the titrator without bubbles, continue to inspect for bubbles as you slowly withdraw the plunger. If you spot a bubble when the titrator is nearly full, remove the titrator from the thiosulfate bottle, hold it over your wastewater bottle, and press the plunger down until the bubbles are expelled. Reattach the titrator to the thiosulfate bottle and continue filling to beyond the zero mark.



Turn the thiosulfate bottle upright and carefully remove the titrator. Hold the titrator over your wastewater bottle and press the plunger slowly downward until the lowermost tip of the black rubber plunger is opposite the zero mark. Inspect the titrator carefully for air bubbles.

12. Insert the titrator into the central hole of the titration vial cap until it snaps into place. Add 1 drop of sodium thiosulfate and swirl the tube (with the titrator still attached) to mix it. Continue this titration process one drop at a time until the yellow-brown solution in the tube just begins to fade or get lighter. The solution should be a pale yellow color - about the shade of pale straw.
13. Gently remove the titration vial cap with the titrator still attached. Be very careful not to change the position of the plunger or to shake any fluid loose from its tip. Add 8 drops of starch indicator solution to the titration tube. The sample solution should begin to turn from pale yellow to dark blue.

 



14. Replace the cap with the titrator carefully on the titration vial and swirl until the solution turns a uniform blue. Continue the titration process described in Step 10. Be sure to gently swirl after each drop. Continue the titration until the solution just turns from blue to clear - the first complete disappearance of the blue color is the endpoint of the titration. (If the solution turns blue again a moment later, ignore it.) Hold the solution against a sheet of white paper (for example, your data sheet) to check the color.

If your sample has a really high oxygen content, you may have to refill the titrator in order to reach the endpoint. Do not completely empty the titrator into the titration sample. The plunger should be lowered only far enough so that the lowermost tip of the black rubber plunger is level with the 10-unit mark on the scale. If you reach this point without hitting the endpoint of the titration, remove the titrator from the titration vial. Refill the titrator to the zero mark again as described in Step 10 and continue the titration.

15. Read the total number of units of sodium thiosulfate used in the titration from the scale opposite the lowermost tip of the black rubber plunger. The divisions are in 0.2 units, but you should be able to read the results to the nearest 0.1 units.

16. Carry out Steps 10 to 15 on the sample bottles marked "B" and "C". If all three titration values are within 0.6 mg/l of each other, average them together and record the result to the nearest 0.1 mg/l as the DO average. If any two titration readings differ by 0.6 mg/l or more, titrate another 20 ml sample from the bottle whose reading fell outside the 0.6 mg/l range. If the second titration still shows a value different from the others by 0.6 mg/l or more then average only the two which fall into the 0.6 mg/l range and record the result as the DO average. If no two of your three original readings fall within a 0.6 mg/l range, repeat steps 10 through 16 using three new 20 ml portions of each sample. Record the results of all titrations (even those you suspect are in error) and average only the two or three values which fall within the 0.6 mg/l range. Discard the contents of the sample bottles in your wastewater bottle.
17. Calculate the percent of saturation by finding the water temperature you recorded at the time of "fixing" on the chart below and comparing the DO average you recorded to the maximum dissolved oxygen concentration for water at that temperature. Divide your average DO measurement by the maximum measurement on the chart and multiply your results by 100. Record this as the percent of saturation for your sample.

Maximum Dissolved Oxygen Concentration

1DISSOLVED OXYGEN TITRATION TIPS

The DO titration is easily the most complicated field procedure you'll be doing. Here are a few tips to help you get through it more efficiently and accurately:

• Be sure your sample bottles are clean and rinsed 3 times with water from your sample bucket.

• After filling a sample bottle, check it carefully for bubbles - the oxygen trapped in the air bubbles will throw off your results.

• Hold the dropper bottles vertically when adding the manganous sulfate (reagent #1) and alkaline potassium iodide azide (reagent #2) solutions. Try to avoid splashing that may introduce air into the sample. Be sure to add the manganous sulfate first.

• Since the sample bottle is supposed to be completely filled, without any air space, some of the sample may overflow as you add the reagents. Don't worry about this.

• The manganous sulfate and alkaline potassium iodide azide solutions are added in excess. The precise number of drops is not critical as long you add enough manganese to bind up all the dissolved oxygen and enough iodide to mop up all the manganese. Try for 8 drops, but if you accidentally add 9 drops instead, that's okay. If you lose count and are not sure whether you've added 7 drops or 8, add an extra one.

• The manganous sulfate and alkaline potassium iodide azide solutions should be added to the samples as soon as possible after collection. Once these reagents and the sulfuric acid have been added and mixed, the samples can be held for up to 8 hours before finishing the analysis (we recommend completing titration within 6 hours if possible). They should be protected from light and kept at or near the temperature of the water they were collected from.

• Allow enough time for the fluffy, white to brownish precipitate (the floc) to settle a third of the way down the bottle (at least to the bottle’s shoulder) after mixings. Impatience may result in an incomplete reaction and false low results.

• The sulfuric acid (reagent #3) is also added in excess - try for 8 drops, but 9 are okay. Adding the acid should dissolve all of the fluffy or "gloppy" precipitate. If 8 drops don't do the trick, continue to add acid one drop at a time until the gloppy precipitate dissolves. You may find that your sample contains dark, solid-looking grains of organic material or sediment that do not dissolve. Ignore these; they will not affect the test results.

• It is critical that the amount of sample to be titrated is measured out carefully. The bottom of the meniscus (the curved surface of the liquid) should be level with the 20-ml mark on the titration bottle

• It is critical that the titration be performed carefully. Before starting, check that the syringe plunger moves smoothly. If it seems to be sticky, lubricate it with a bit of sodium thiosulfate solution. (Remember to rinse it with fresh water when you get home.) If the problem persists, report it to the Monitoring Coordinator.

• Check the titrator carefully for air bubbles after filling. The volume taken up by the bubbles will produce inaccurate readings of the volume of thiosulfate solution used in the titration. Do not proceed with the titration until your titrator is full and bubble free.

• Measurement of the amount of thiosulfate solution used in the titration is critical. At the start of the titration, the lowermost tip of the black rubber plunger should be level with the 0-unit mark on the top of the titrator scale. Handle the titrator carefully after filling it, taking special care not to move the plunger inadvertently. Moving the plunger accidentally downwards will expel solution; moving it upwards will draw air into the syringe.

• If your sample contains more than 10 mg/l dissolved oxygen, you will have to refill the titrator during the titration. This is especially likely to happen if you're sampling water that can hold more oxygen - i.e., cool water (less than 10°C or 50°F) or water with an unusually low salinity. One tip-off that you've got high oxygen levels is that when you add the sulfuric acid, the solution turns a brown-orange color as lots of iodine is created.

• As the plunger approaches the bottom of the titrator, be sure not to depress the lowermost tip of the black rubber plunger below the 10-unit mark on the titrator scale. If you depress the plunger further, you are adding an unknown volume of thiosulfate to your titration sample. When the lowermost tip reaches the 10-unit mark, remove the titrator from the titration tube and refill the titrator.

• Exactly when and how much of the starch indicator solution is added is not critical. The important thing is that the sample turns blue. If you have a sample with low oxygen levels, adding the sulfuric acid may cause it to turn a pale yellow or pale straw color before you've added any thiosulfate at all. In this case, you'll want to add the starch indicator before you start the titration. It's always better to add the starch solution a bit too early than too late.

• Once you've reached the pale-yellow color and added the starch indicator, proceed with the titration slowly and carefully so that you don't overshoot the endpoint.

• If the sample fails to turn blue when you add the starch, this means that you've already added too much thiosulfate and overshot the endpoint. If this happens, or if you overshoot after adding the starch, discard the results of this titration. Measure out a second titration sample from the same sample bottle and repeat the procedure.

• The first complete disappearance of the blue color is the endpoint. If you see the solution turn blue again a moment later, ignore it! The "re-bluing" effect is caused by the interference of other chemical compounds in the sample.

Nutrients

When feasible, nutrient testing should be performed on site; however, in inclement weather it is permissible to label the 250 ml sample bottles provided in your kit with the date and your site name and fill them with water from your sample bucket to be taken home for testing. If you do this, you must keep your samples cool (between 4°C and 10°C) and complete all testing within six hours of sampling.

Ortho-Phosphate

1. Rinse 3 test tube from your LaMotte Phosphate Test Kit three times with sample water and fill them to the 10ml line with water from your sample bucket.
2. Use the 1ml pipet to add 1ml of Phosphate Acid Reagent to one of the three sample tubes. Cap this test tube and mix by repeatedly inverting it for five seconds.
3. Use the 0.1g spoon to add one level measure of Phosphate Reducing Reagent. Cap the tube again and mix for another five seconds or until all powder is dissolved. Wait five minutes.
4. Place the Axial Reader on a flat surface with the label facing away from you.
5. Insert the Low Range color comparator into the Axial Reader with the labels and blue vials facing toward you.
6. Insert the ampule of distilled water into the square hole on the left side of the comparator.
7. When it has been five minutes, remove the cap from the sample test tube to which you have added the reagents and insert it into the slot in the Axial reader which is directly behind the distilled water ampule.
8. Insert the two test tubes of untreated sample water into the slots in the Axial Reader on either side of the sample tube.
9. Slide Axial Reader up until the top of the Reader is even with the top of the color comparator.
10. Place the comparator so that natural light (or strong fluorescent light) shines down through the test tubes.
11. Compare the color in the center (sample) test tube to the colors in the top left corner of the comparator. If the color of your sample is darker than these color standards move the Axial Reader down so the bottom is even with the bottom of the comparator and compare the center tube to the colors in the lower left hand corner of the comparator. If your sample is still darker than the color standards, move the ampule and all three test tubes to the right side of the comparator and Axial Reader and repeat the comparison process.
12. Once you have matched the color in the sample tube to a color standard, note the shade of blue (clear, faint, light, medium, dark) of the sample on the Monitor Data Sheet.
13. Record the number of the matching color standard as Ortho-Phosphate in ppm on your data sheet.

Nitrate/Nitrogen

1. Rinse one square test tube from your LaMotte Nitrate Nitrogen Tablet Kit three times with sample water and fill it to the 5ml line with water from your sample bucket.
2. Add one Nitrate #1 Tablet to the tube. Cap the test tube and mix by inverting repeatedly until the tablet dissolves completely.
3. Add one Nitrate #2 CTA Tablet to the test tube. Cap the tube again and mix until the tablet dissolves completely. Wait for 5 minutes.
4. Repeat steps 1 through 3 using the second test tube from your Nitrate Nitrogen Tablet Kit.
5. Insert the Nitrate-N color slide into the Octa-Slide viewer.
6. Insert the first test tube into the top of the slide viewer.
7. Note the shade of pink (clear, faint, light, medium, dark) of the sample on the data sheet.
8. Match the sample color to a cell of the color slide and record the number of that slide as Nitrate-Nitrogen in ppm on your data sheet.
9. Repeat steps 6 through 8 with the second test tube in order to verify your results.
10. Multiply the color slide number by 4.4 and record the result as Nitrate in ppm.

Coliform Bacteria

1. Use your sharpie to mark the lids of 3 bottles of Coliscan Easygel™ with the numbers 1, 3 and 5. Use the sterile pipet included in your kit to carefully draw a 1ml water sample from your sample bucket and deposit it into the Easygel™ bottle you have marked as 1. Next, carefully draw and deposit a 3mL water sample from your bucket into the bottle of Easygel™ marked with a 3. Repeat the process once more, this time drawing and depositing a 5mL sample into the bottle marked 5.

2. Mark the lids (the larger half) of three pretreated petri dishes with the date, the time, the name and number of your sampling site, and the amounts 1ml, 3ml and 5ml. (Keep your writing close to the edge of the lids). Match the bottles of Coliscan-water mixture to the petri dishes marked with the same number. One at a time, pour each bottle of Coliscan-water mixture into the bottom half (the smaller half) of its respective petri dish. Cover the dishes with the designated lids and gently swirl the liquid so that it covers the entire bottom of the dish.
3. Place the petri dishes containing the Coliscan-water mix in a warm place and incubate for 24 to 48 hours.

 



 

4. After about 30 to 40 minutes the Easygel™ will set into a gel form. Once this occurs turn each entire petri dish over and continue incubating.
5. After 24 hours have past, count the number of purple colonies that have formed in the petri dish. (Using the quadrant grid on your Coliscan Data Sheet will facilitate counting). This is the fecal coliform (E. coli) count for this sample. Next, count the number of pink or red colonies and add this to the fecal coliform count. This is the total coliform count for the sample. Record the fecal and total coliform counts for each sample (1ml, 3ml and 5ml) in the 24 hour incubation spaces on your Coliscan Data Sheet. Repeat this counting procedure after a total of 48 hours have past since plating and record the results on your Coliscan Data Sheet in the 48 hour incubation spaces and on your Monitor Data Sheet.