HONOLULU — Recent samples taken from the inner wall of a Princeville water tank — part of a private water system — have been confirmed to contain the organic chemical polychlorinated biphenyls, according to state officials. While they say the
HONOLULU — Recent samples taken from the inner wall of a Princeville water tank — part of a private water system — have been confirmed to contain the organic chemical polychlorinated biphenyls, according to state officials. While they say the water remains safe to drink, the source of contamination has yet to be determined.
PCBs have been banned in the United States since 1979, after being linked with several health conditions, including cancer, liver damage, low-birth weight and lowered immune system.
The samples were tested as part of an ongoing investigation to determine the source of the PCB contamination announced in December, according to a press release Saturday by the state Department of Health.
PCBs do not dissolve well in water. Despite being found in a water tank, monitoring on the drinking-water distribution system has determined the chemical is not in Princeville’s drinking water, according to DOH officials, who said intense and regular testing has confirmed the water served to the public is safe.
“The department continues to sample Princeville drinking water. We have confirmed that PCBs are not reaching people’s homes,” DOH Deputy Director for Environmental Health Gary Gill said in the release. “Our Safe Drinking Water Branch is working closely with Princeville Utility Company to assure that their work to fix this problem will continue to protect the public.”
However, DOH officials said the contamination source remains unclear, and efforts to remove the contamination are advancing under DOH’s supervision.
On Dec. 14, DOH announced that contaminants had been found in a water reservoir in Princeville. DOH and the Princeville Utilities Company Inc., owner and operator of the private Princeville water system, took immediate action to maintain the quality of the water. The water system serves about 2,200 people on Kaua‘i’s North Shore, the release states.
On March 14, DOH learned that scrapings from the inner wall of the Princeville water tank were confirmed to contain PCBs. Aroclor 1254, one component of PCBs, was found at 2,600 parts per million. Another component, Aroclor 1260, was also found at 2,100 ppm.
Proof is in the caulking
The caulking on the outside of the tank was also tested and was found to contain PCBs, according to DOH.
Concrete caulking compounds containing PCBs were sometimes used in expansion joints in concrete structures erected prior to 1980. The Princeville water tank was built in 1971.
Commercial production of PCBs ended in 1977 because of health effects associated with exposure.
In 1979, the U.S. Environmental Protection Agency banned the use of PCBs, however, PCBs may still be present in many pre-1979 products, DOH states.
PUCI, with DOH approval, decided to take the contaminated tank out of service to clean it. PUCI will remove an oily residue from the inner tank wall to help ensure that the chemicals do not leach into drinking water.
PUCI will install three new temporary 20,000-gallon water tanks to bypass the 1.5 million gallon tank. During the bypass operation, residents will be urged to conserve water.
For more information, contact Mike Loo of PUCI at 826-6100.
Weekly testing
The DOH has directed PUCI to continue weekly water testing to determine if PCBs are present in the distribution system and in sample water skimmed from the tank water surface. These samples are sent to CalScience Laboratory in California for testing. The Calscience Laboratory is certified by the DOH to run PCB analyses. The DOH is also conducting monitoring twice a month to ensure that PCBs have not entered the drinking water distribution system.
The federal and state Maximum Contaminant Level for PCBs in drinking water is 0.5 parts per billion at the compliance sampling point, which is immediately after the 1.5 million gallon water tank. This standard is set to avoid health risks based on a lifetime of consuming water containing that level of contaminant.
PCBs are a group of organic chemicals formerly used in the U.S. in hydraulic fluids, plasticizers, adhesives, fire retardants and de-dusting agents.
To date, the Princeville water system is in compliance with federal and state PCB standards for drinking water, according to DOH.
