How to Clean Out a Private Well – Suspected of PCB Oil Contamination- From Well Pump

How to Clean Out a Private Well – Suspected of PCB Oil Contamination

This post was developed following a private well owner outreach program in Pennsylvania.  Where the homeowner suspected this was a problem.

Prior to the 1978 ban most of the well pumps used a PCB capacitor.    After 1978, the capacitors were required to be marked at the time of manufactured to state that the did not contain PCB, i.e., “No PCBs”. In some cases the the PCB capacitors would leak the PCB (oil coolant) into the motor.  If the motor or motor seal fail, the coolant would leak into the well.   This would introduce PCBs to your water.  When the water is heated, vapors would be generated or you may observe an oil residue or film.  Polychlorinated biphenyls (PCBs) are a group of manufactured organic chemicals that contain 209 individual chlorinated chemicals (known as congeners). Concentrated PCBs are either oily liquids or solids and are colorless to light yellow in color. They have no known smell or taste. “PCBs are not very water-soluble so it is quite rare for them to be found in groundwater. Some submersible pumps found in private wells have been recalled because PCB containing oils had been used in their manufacture. When these pumps fail these oils can leak out into the drinking water. ”  The available data suggests that  PCBs are probable human carcinogens and can suppress the immune system.

“The procedure for cleaning a well and plumbing contaminated with PCB oil is essentially the same as for “clean” oil with the exception of certain requirements concerning storage and disposal explained later in this document. The professional servicing the well should follow the procedure outlined here:

Step 1 Remove the failed pump from the well. Place it into a DOT-approved 55-gallon drum for disposal. Allow water within the well to remain still for a least 24 hours.

Step 2 Remove all free floating oil from the surface of the water in the well using a bailer and/or oil absorbent pad or boom. Place it into the drum with the pump.

Step 3 Make certain that there is no floating oil layer in any plumbing fixtures such as water heater or toilet. If there is, remove with oil absorbent pad.

Step 4 Put approximately 8 ounces of dishwashing liquid per 100 gallons of well volume into the well. (Assume 1.5 gallons/ft. of water for a 6″ diameter will and 53 gallons/ft. for a 36″ diameter well.) Detergent should be pre-mixed in a little hot water to be sure that it creates the maximum suds.

Step 5 Recirculate the well water using a garden or other hose connected to a hose bib while running the water back into the well. Allow it to agitate for 1 hour. In the case of a low yielding well or during a period of drought, be sure to take precautions not to run the well dry. The length of time for agitation may need to be reduced in some cases. Place the hose into the drum for disposal when finished.

Step 6 Wash down the sides of the well with a clean or new garden hose, preferably equipped with a pressure nozzle.

Step 7 If household plumbing has not been contaminated, skip step 7 and proceed to step 8. If household plumbing is also contaminated, run the soapy well water through the plumbing system for 3-4 hours, until it is no longer soapy. This can be accomplished by running all the faucets (not so long that the well runs dry) and periodically flushing the toilets. Run both hot and cold faucets so that the hot water heater is cleaned as well. If after step 7 water still runs soapy, turn off faucets and proceed to step 8.

Step 8 Pump soapy water directly from the well to a municipal sewer, or if not available, run a hose so that the water may be discharged directly to the septic tank.

Step 9 Obtain a water sample directly from the well then properly seal the well (i.e. chlorination, etc.). Also, a sample should be collected from a household tap.

Step 10 Run empty loads in both the dishwasher and washing machine using only the normal soap for each.

The homeowner should submit the water samples to a laboratory for PCB analysis to confirm the success of the cleaning and the safety of their water. They must also contact a permitted transporter to arrange for proper disposal of the drum of PCB waste.

Source of the protocol:
Department of Energy and Environmental Protection
Bureau of Materials Management and Compliance Assurance
PCB Program
79 Elm Street
Hartford, CT 06106-5127″

“Protocol posted for informational purposes – it is critical for the homeowner to hire an expert to assist with this work”. This is not a DIY – Do it Yourself Project.


Low cost PCB screening Test– includes metal, other organics, and general water quality.