| Common household bleach can used in an | | | | on. Let us say this amount is 20 gallons. |
| automatic chlorinator system to kill coliform | | | | 4. When pump turns on, immediately close faucet |
| bacteria and provide disinfected water. In some | | | | and start timing pump cycle. |
| wells iron or sulfur bacteria can create 'rotten egg' | | | | 5. When pump turns off, record pump cycle time |
| odors and cause staining of fixtures and | | | | to refill pressure tank in seconds. Let us say this |
| appliances. Chlorinators can also be used to | | | | figure is two minutes or 120 seconds. |
| address these problems. | | | | 6. Divide the number of gallons collected in Step 3 |
| The first step in selecting a chlorinator is to find | | | | by the number of seconds in Step 5. 20 divided |
| out your basic water chemistry and have your | | | | by 120 is 0.166 |
| well water tested. A general mineral analysis will | | | | 7. Multiply the answer from Step 6 by 60, which |
| provide a list of the common minerals (calcium, | | | | comes out to 10. |
| magnesium, iron, manganese, dissolved solids) | | | | 8. The answer in Step 7 is the average pumping |
| alkalinity and pH. The pH is important because the | | | | capacity of the pump in gallons per minute (GPM). |
| higher the pH the more chlorine is required. | | | | Now that you know the amount of chlorine you |
| How Much Chlorine Should I Plan to Add? | | | | want to install (3 ppm) and the flow rate of the |
| Chlorine is injected in parts per million ('ppm') which | | | | water stream you are injecting the chlorine into |
| is the same as saying milligrams per liter ('mg/L'). | | | | (10 gallons per minute) you are finally ready to |
| For bacteria you want 1 to 2 ppm of chlorine and | | | | calculate the size of the metering pump! |
| approximately 10 minutes of contact time. If the | | | | How Strong Should the Chlorine Bleach Solution |
| water is colder than 50F you may need longer | | | | Be? |
| contact time. | | | | Use unscented 5% chlorine laundry bleach and |
| For each part per million of iron or manganese | | | | dilute it by adding 9 gallons of water to 1 gallon of |
| you want to inject 1 ppm of chlorine. For each 1.0 | | | | bleach. This will give you a solution strength of |
| ppm of hydrogen sulfide gas (which causes the | | | | 5000 parts per million of chlorine. |
| rotten egg smell in water) you want to inject 2 to | | | | Metering Pump Sizing |
| 3 ppm of chlorine. | | | | Metering pumps are often rated in the amount of |
| So say you have bacteria and 2.0 ppm of iron. | | | | chlorine solution they can pump by gallons per day. |
| For our example here, we will assume you want | | | | They have adjusting knobs so you can pump the |
| to inject 3 ppm of chlorine. | | | | full output or turn the pump down to deliver up |
| How Do I Know What Size Chlorinator Pump to | | | | 90% less than the output. |
| Install? | | | | The formula simple: multiply the flow water (GPM) |
| The next step in selecting your metering pump is | | | | times the Applied Dosage in Parts Per Million and |
| to know how many gallons per minute your well | | | | them multiply this by 1440 (the number of |
| water is flowing at the point where you will be | | | | minutes in on 24 hour period). Finally divide this |
| injecting the chlorine. Usually the best place to | | | | number by the solution strength being used. |
| inject the chlorine is before the pressure tank. | | | | 10 GPM x 3.0 PPM x 1440 divided by 5000 = 8.6 |
| Unless you have a variable-speed pump, your | | | | Gallons Per Day |
| water at this point is flowing in approximately the | | | | At this rate you can select a metering pump that |
| same flow rate every time the well pump turns | | | | can pump 10 gallons per day and adjust the |
| on. After you use up your reserve in your | | | | output of the pump to 86% to achieve the |
| pressure tank, the pressure switch turns on the | | | | desired 8.6 gallons per day. Finally you can test |
| well pump and the water begins to flow from the | | | | the chlorine residual at the kitchen sink. Your goal |
| well. | | | | should be to have a residual of 0.2 to 0.8 ppm of |
| You can easily calculate the flow rate at this point | | | | chlorine. If you find the residual is too high, you |
| by following these steps: | | | | can adjust the metering pump down to deliver |
| 1. Open any hose bib or faucet until pump turns | | | | less or dilute the chlorine solution with more water. |
| on. | | | | If you find the residual is too low, you can make |
| 2. Close hose bib or faucet and let pump fill up | | | | the solution strength stronger by using less water |
| pressure tank until it turns off. | | | | to dilute the solution, or you can turn up the |
| 3. Using a 1 or 5 gal. bucket, open faucet, collect | | | | output of the metering pump. |
| and measure all water discharged until pump turns | | | | |