These are general guidelines for chlorinating a domestic well after the failure of a bacteriological test for Total Coliform Bacteria.
It is a general accepted practice to try this procedure first before installing permanent treatment equipment. Chlorinating will chemically sterilize the well and all associated plumbing. After all of the chlorine has been flushed from the system and you can not detect any traces of chlorine, you must then put the water system in to normal use and wait an additional 7 – 10 days before retesting.
The procedure described below will chlorinate the water to 25 parts per million. This is a very high level of chlorine. For comparison chlorinated city water is about 0.5 to 1 part per million.
If you are not familiar with the plumbing aspects of your water system, we recommend you contact your local pump company to do this.
Until your water supply has been tested and is certified as safe, boil all water for at least 10 minutes at a rolling boil before drinking or cooking with it.
FOLLOW THESE STEPS TO FIGURE THE AMOUNT OF
HOUSEHOLD LIQUID BLEACH YOU WILL NEED
You may use any brand of house hold bleach that is at least 5.5% Sodium Hypochlorite.
First you must know the number of gallons of water in your entire system that you are going to treat. Use the following calculation to arrive at this figure.
1. Multiply the depth of your well times 1.5 – This equals the number of gallons of water in your well.
2. Add the number of gallons in your pressure tank.
3. Add the number of gallons in your holding tank (if you have one).
EXAMPLE: 100 foot well x 1.5 = 150 gallons of water in well
+ 40 gallons for pressure tank
+1500 gallons of water in the holding tank
=====
1690 Total gallons of water to treat
To arrive at the correct amount of bleach to use, see the example below:
EXAMPLE: 1690 gallons divided by 496 equals 3.4 quarts of bleach.
Divide 3.4 by 4 and this will give you 0.85 “gallons.”
When the bleach has been added to the water this will raise the amount of chlorine to: 25 PARTS PER MILLION
* * CAUTION * *
DO NOT USE THIS WATER FOR ANY PURPOSE
THIS INCLUDES DRINKING, COOKING, BATHING, WASHING
CLOTHES & AUTOMOBILES, WATERING LIVESTOCK AND
IRRIGATING LANDSCAPE
DIRECTIONS FOR ADDING HOUSEHOLD BLEACH TO YOUR WATER SYSTEM
DISCONNECT OR BYPASS ALL TREATMENT EQUIPMENT PRIOR TO
PERFORMING THE FOLLOWING. THIS INCLUDES WATER SOFTENERS, FILTERS, CARBON TRAPS, ETC…
1. Unscrew the screened return bent vent on the sanitary seal of the well. Do not remove the 4 hexagon shaped bolts that hold the well seal together. If you do not have a screened return bent vent, call Neilson Research Corporation at 541-770-5678.
2. Attach a garden hose to a faucet nearest the well. A small nozzle will be required to adapt the hose to the 1/2 inch opening in the sanitary seal. Using a funnel, pour the correct amount of bleach into the well. If your system includes a holding tank of 500 gallons or more, put a proportionate amount of bleach into the holding tank.
3. Using the hose nozzle, allow water to run into the well. Once the bleach has been introduced into the well, it must be recirculated through the entire water column. This may take anywhere from 1/2 hour to 3 hours or longer, depending on the flow rate through the hose and the depth of your well (about 1 hour per every 100 feet). Remove the hose periodically and check for a strong chlorine odor in the water.
4. After chlorine can be detected in the garden hose, reinstall the screened return bent vent to the sanitary seal. Go into the residence and turn on each hot and cold water faucet until you smell bleach coming out of the faucet. Turn the faucet off and do not use it. Continue this procedure with each water tap throughout the residence.
5. Allow the entire system to sit overnight without any usage.
* * CAUTION * *
DO NOT USE THIS WATER FOR ANY PURPOSE
THIS INCLUDES DRINKING, COOKING, BATHING, WASHING
CLOTHES & AUTOMOBILES, WATERING LIVESTOCK AND
IRRIGATING LANDSCAPE
FLUSHING THE SYSTEM
1. Attach a garden hose to an outside faucet. Turn on the water and allow this water to run at a moderate flow. Do not run it into the septic system or onto landscaped areas. Allow the water to run for approximately 2 hours, then turn it off for approximately 1 hour. Continue this alternating procedure until you cannot detect any chlorine odor coming out of the hose.
2. You are now ready to flush the water lines in the residence. Turn on each water faucet, one at a time, to clear the lines. The small amount of chlorine in the lines will not harm the septic system.
3. After you have flushed the system and no chlorine odor can be detected, put the system back into normal usage for 7 to 10 days. Try and use lots of water during this period.
4. You should continue to boil water for your cooking and drinking until you have retested the system and it is found to be free of contamination.
5. At a minimum of 7 days after chlorination, you should bring in another water sample for testing. If this sample is free of contamination, you only need to retest your water every six months. This will insure that your system has remained free of Coliform bacteria.
Neilson Research Corporation can also test your water for toxic heavy metals and trace minerals. If you have a problem with water spotting, staining of fixtures, metallic taste, or build-up of soap scum around the sinks and bathtubs, talk with any of our personnel regarding what analyses might be indicated for your water. Neilson Research Corporation can also test for toxic organic chemicals, herbicides, and pesticides.
We are here to provide exceptionally high quality laboratory analyses. We are open from 8:30 to 5:00, Monday through Friday.