Methods of Disinfection:
If you've had your water tested at a certified lab and it is determined that you have a positive test result for Coliform or E. Coli with a plate count, it will be necessary to treat the water to make it safe for human consumption. Or you may just have iron bacteria or sulfur (also bacteria related) and you may want to get rid of those because they are a nuisance. Sulfur has a smell like rotten eggs and iron bacteria can grow in the well casing and water lines and plug up pumps, softeners and other water treatment systems. There are different ways to treat the water.
We offer different solutions as follows:
The Stenner Chemical Feed Pump:
This method of treatment, using peroxide or chlorine works on low producing wells or shallow wells also because it is installed with a retention tank that allows for contact time to kill the bacteria. The feeder pump is installed on top of a 15 gallon solution tank which draws the chemical from the tank and injects it into the line before the retention tank where it gathers for contact time.
Frequently common household bleach (unscented Clorox is NSF approved) is used with an approximate mixing rate of one gallon of bleach to three gallons of water. Sometimes it is necessary to use pool chlorine (12% chlorine) if the well contains a high rate of TDS (total dissolved solids) which consists of all the combined particles in the water. TDS can be elevated for instance if there is a high sodium level combined with greater amounts of iron or hardness. We have had great success with peroxide (7%) also, especially with excessive sulfur and/or iron. Peroxide is a 16 times better oxidizer than chlorine and works instantaneously, therefore, needing less contact time and a smaller retention tank than does chlorine.
When using chlorine it is important to occasionally check for a chlorine residual with a pool test kit. To find out if the residual is in a normal range, one would draw approximately 1/2 gallon of water off through the valve located in the line near the top of the retention tank into a container and then fill the small vial included in the pool test kit up to the line. (If there is a water storage tank in use the test kit vial could be dipped into the tank directly or taken from a valve near the tank). Then using the OTO chemical (yellow cover) add 5 drops to the vial of water to test for a chlorine residual. Compare the color of the treated water to the chart shown at the left to see if the level of chlorine in the water sample is in the range of .5 - 1.0. If it is too high or low the solution rate needs to be adjusted. Also if there is excessive sulfur it may be necessary to run a slightly higher chlorine residual to eliminate the strong sulfur odor.
Sometimes a mixing valve is added at the injection point to accelerate the mixing process. It works well if there is excessive sulfur in the water. The Carbon Filter is installed after the Retention Tank to remove chlorine or peroxide for drinking purposes. When using chlorine It is important for the life of the Carbon Filter bed to maintain an appropriate chlorine residual so that the media doesn't break down quickly from too much chlorine going through the system. PLEASE NOTE USING TOO MUCH CHLORINE CAN WEAR DOWN THE CARBON BED FASTER.
Ultra Violet Sterilizer:
The Ultra Violet Sterilizer is used in situations where there is present in the water E. Coli or Coliform bacteria. A certified lab must test for these types of bacteria. If a test result for either produces a positive result with a high plate count a U. V. Light would be necessary to kill the bacteria. An Ultra Violet light is installed on the water line after the pressure tank and is preceded by an in-line filter housing to filter out sediment before the water passes through the lamp. When the water passes through the lamp it is exposed to ultra violet rays that kill the bateria on contact. The water passes over a quartz sleeve that surrounds and protects the light bulb. If iron bacteria is present in the water the U. V. light is not recommended because it can create a film over the quartz sleeve and the ultra violet rays cannot penetrate the film and effectively kill the bacteria. Note that if a positive test result produces an excessively high plate count such as 5,000 or above a stronger U. V. lamp may be needed with a dosage rate of 60,000 microwatt seconds per square centimeter to kil all the bacteria effectively. PLEASE NOTE THE ULTRVIOLET SYSTEM DOES NOT REMOVE SULFUR (which is bacteria related).
B & B Pellet Feeder:
The pellet feeder is another way to treat water for E. Coli, Coliform, Sulfur, Iron Bacteria and several other water born bacteria's. This is also effective with higher plate counts from positive bacteria test results. The Chlorine pellet feeder is installed on top of the well casing and drops pellets directly into the well periodically when the water is used and is a constant treatment. This method can be used to treat the water at the source, before the pressure tank. However, the requirement for this method of water treatment would be to have a deep enough well with plenty of standing water because chlorine needs contact time with water to kill the bacteria effectively. For example: 100' well depth with a 6" casing and 80' of standing water is equal to 120 gallons, which allows for enough contact time. The pellet feeder would then be followed by a 1 cube Carbon Filter that would be installed in line after the pressure tank to remove the chlorine. The Carbon Filter would probably be set up to backwash once or twice a week (during the night) to flush the impurities out of the system. To check the system to insure a proper chlorine residual is maintained, periodically a sample of water may be drawn after the pressure tank (before the Carbon Filter) into a bucket and then into the vial of the pool test kit. Fill the vial up to the line indicated and add 5 drops of OTO (yellow cover) and compare the treated sample to the indicator at the left to see if the residual is in the range of .5 - 1.0. If the reading is too high or too low the pellet feeder may need to be adjusted accordingly.