FAQ : Liability Risk Caused by Using Regenerated Resins for PCB Closed-Loop Water Recycling

What is the Potential Liability Risk Caused by Using Regenerated Resins for PCB Closed-Loop Water Recycling?

Reducing operating costs by using regenerated instead of disposable ion-exchange resin (see definitions in Technical Bulletin #4) can be illusory and be a serious liability risk by the user. Some cleaner manufacturers offer "one stop shopping", but are really using third and fourth party suppliers. The purchase order might go to one supplier, but the actual service might be going to a third or fouth supplier. Whether the third party is known or unknown to you, your liability does not stop. The greater the number of companies handling the resin, the greater the probability of increasing your liability. Your heavy metal lead may be going to places that could be a serious liability such as:

1. Local water treatment dealer "mixes-up" lead contaminated resin with resin used by kidney dialysis patients, residential, research laboratories and other sensitive users
There are many local water treatment dealers in the USA and around the world who treat tap water with regenerated resins, but very few specializing in heavy metal ion-exchange regeneration. A customer using such a dealer trusts that none of his resin ever has a chance of being exposed to any lead-contaminated wastewater! As long as any lead-contaminated resin is in a regeneration facility with both kinds of resins, there is a always a chance of operator error. The health hazards to kidney dialysis patients, failure of a long term study by a research laboratory etc. can result in a liability lawsuit.

2. Unknown disposal of lead from the resin
The user is still liable for the lead generated by his facility regardless where it goes according to a court of law. Knowing the waste hauler and the final destination of the lead is critical to a lead generator. Do the suppliers have a proper discharge permit? Have they violated discharge laws in the past? Are they giving the resin to other parties who dispose of it properly? What is their reputation and length of time in business? Do they have properly trained personnel to handle the resin? These are some of the many factors that must be considered in qualifying a supplier.

3. Chelating Resin
Most cleaner manufacturers use the services of a non-wastewater treatment (third and fourth party) regenerator. Since they do not offer an ion-exchange resin service, they depend upon this method to allow them to sell their system. One technical paper (1) promoting this procedure recommends the use of a chelating resin to prevent lead from going into another resin. This other resin is then supposedly "free of lead" and then can be used by other users of ion exchange resin. The customer must depend upon careful testing by maintenance personnel to determine when there is a break through of lead and other contaminants from the wastewater. Since testing is not continuous and therefore, the chance of lead and other contaminants entering the "good" resin is high. Excerpts from the paper follow:

"This resin bed [chelate tank] is where all of the hazardous contaminants get concentrated, and is needed in order to regenerate the following beds without contaminating them".

Fact: ion-exchange resin is not an absolute filter, that is, there are passageways between the resin beads that can allow the lead-contaminated water to go through the chelate resin tank.

"We provide a sample container to automatically collect water samples at specific intervals and volumes for testing These monthly tests indicate the heavy metal loading of the chelate resins and will allow ample time for their replacement."

Fact: The chelate resin is not a barrier filter, there are passageways between the resin beads that allow very small quantities(ppb or less) of lead to pass all of the time, and toward the end of its life, the resin will actually pass as much lead as enter the chelate tank. There are serious concerns that must to be considered

• Sampling method: The automatic sampler is not fool-proof. For example, suppose the inexpensive sampling solenoid valve does not operate correctly and an operator does not take the proper corrective action or take the sample properly, or by error.
• Representative sample: After many samples are taken in one container and the chelate resin becomes exhausted, a sample of lead-contaminated water is taken automatically. This last sample (with ppb or ppm lead) will be diluted with very low lead-contaminated (with ppt or ppb) water already in the container. Now the detection of lead is much more difficult and is not representative of the lead in the water now going to the DI tanks following the chelate resin. The proper procedure is to sample the most recent lead-contaminated water only. This is not possible with the method being used.
• Sample analysis: An incorrect lead analysis by the laboratory or by the operator to determine when to replace the chelate tank is always possible.

All of the above allow lead-contaminated water to enter ion-exchange resin tanks, supposedly lead-free, to go to a regenerating facility that is suppose to get only lead-free resin! The lead-generator can be exposed to potential serious liability by allowing a regenerator's high purity water resins to cross-contaminate with lead-contaminated resins.

(1) J. Banis, "Aqueous SMT Cleaning Coupled with Closed-loop Water Treatment", Nepcon
West 1993 proceedings, February 10, 1993 (call for a copy of this paper)

Some factors to consider when choosing between regenerated resin and new resin:

• Single source for servicing and disposal of lead-contaminated resin
• Reliable supplier and knowing the destination for the heavy metal lead
• Risk liability of having inexperienced suppliers unknowingly or deliberately use lead-contaminated resin for medical, laboratory or other applications.
• Supplier has a facility that has a proper discharge permit and a reputation for proper operation of regeneration facility.