Well_Disinfection_Procedure.pdf

D ep ar tm en t o f H ea lth

L ee

C ou nt y

E nv iro nm en ta l E ng in ee rin g

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. D an le y

D riv e, U ni t 1

Fo rt M ye rs

, F L

WELL

DISINFECTION

PROCEDURE

SCHD061003B

Published by the Environmental Engineering Section of the Department of Health – Lee County

Telephone: (239) 274-2200 Fax: (239) 274-2201

If you suspect that your water supply is contaminated with harmful bacteria, we suggest that you call a state-certified laboratory to verify your concerns before undertaking any of the techniques outlined in this document.

If your water supply has been tested by a state-certified laboratory and found bacteriologically unsafe for drinking, the following procedure can be followed.

NOTE: We highly recommend that you hire a certified well contractor or water system operator to chlorinate your well. The Flor ida Depar tment of Heal th in Lee County assumes no responsibility for any use of the information contained herein or any loss resulting there from.

This procedure should not be confused with routine maintenance. Repeated doses of high chlorine concentrations can damage equipment such as softeners, bladder tanks, or septic systems. Maintain your system in good working order and perform disinfection only when absolutely necessary

Chorine Use only a liquid sodium hypochlorite solution such as common household bleach or pool chlorine. Do NOT use scented bleach or stabilized pool chlorine tablets. Also, be aware that pool chlorine solutions have a limited shelf life. If your pool chlorine is more than 2 weeks old, assume that it is no longer effective.

Before You Begin Since chlorination procedures can take as long as 8 hours, store enough water for consumption and cooking purposes. If you suspect that the water is bacteriologically unsafe, boil or add chlorine to the stored water (see Emergency Disinfection of Drinking Water link below.) Also, plan ahead. We recommend that you chlorinate your system in the evening and let it sit overnight.

Disinfection

1. Turn off the electrical power to the well pump.

2. If your well has a chlorination port, open the port.

3. If your well does not have a dedicated chlorination port, remove the plastic bolt from the view port in the sanitary seal. Using a clean plastic or glass rod (a standard ball-point pen works fine here), check the view port to see if the neoprenes well seal material has clogged the hole.

If it has, a standard power drill can be used to (CAREFULLY) open up the hole. You will also need a small funnel.

4. For wells 4” in diameter or less, we recommend that one quart of common household bleach or two cups of pool chlorine be poured down the well casing for each 20’ of depth.

5. For wells 6” or 8” in diameter, one gallon of bleach or ½ gallon of pool chlorine should be poured down the well casing for each 20’ of depth.

6. After the chlorine has been poured down the well, allow the highly chlorinated water to stand in the well for a minimum of 60 minutes.

7. Turn on the pump and pump the chlorinated water through the water system. Every outlet, including outside hose bibs, should be allowed to run until a strong smell of chlorine is detected.

• Do not run large volumes of this water into a drain leading to your septic tank.

High chlorine levels may do heavy damage to septic systems.

• Notify all users of water that a large amount of chlorine is in the water system and that the water should not be used for drinking, cooking, or bathing until the chlorine is flushed from the system. (Toilet flushing is okay if necessary)

8. When chlorine can be detected at each outlet, turn the water off and let it sit for 6-8 hours.

(Overnight is a good time to do this.)

View Port

Figure 1: Sanitary seal

Flushing the System

If your system has an aerator, drain it first by removing the drain plug at the bottom of the unit.

Then refill it with fresh water before flushing the system.

If your system does not have an aerator, run raw water taps and / or hose bibbs to flush the majority of the highly chlorinated water from the system.

Once the aerator has been drained or there is no odor of chlorine from the outside taps, open all other outlets, including sinks, and flush the toilets until the chlorine odor is no longer detectable.

When you have completed the above procedure, please contact a state-certified laboratory so that a sample can be taken.

A Public Service of the Department of Health- Lee County Environmental Engineering 60 S. Danley Drive, Unit 1 Fort Myers, FL 33907 Telephone: (239) 274-2200 Fax: (239) 274-2201

Emergency Water Disinfection Link http://www.cdc.gov/healthywater/emergen cy/safe_water/personal.html http://www.cdc.gov/healthywater/emergency/safe_water/personal.html