PFAS Detected in Waialua Sugar Pump 2 System

Posted on Nov 29, 2023 in Newsroom

HONOLULU – Chemicals known as PFAS (perfluoroalkyl and polyfluoroalkyl substances) have been detected for the first time in water samples collected at the Waialua Sugar Pump 2 water system (Public Water System HI0000309) that serves approximately 500 people in the northwest area of the island of O‘ahu.

PFAS at the Waialua Sugar Pump 2 water system were confirmed in lab reports dated August 30, 2023, and November 13, 2023. The water system notified the Department of Health (DOH) of the initial detection of PFAS through an email on November 16, 2023. The detected PFAS levels are below the Environmental Protection Agency’s (EPA) proposed Maximum Contaminant Levels (MCL) for PFOA and PFOS. The Hazard Index based on the PFBS detection is 0.015 which is below EPA’s proposed 1.0 compliance threshold. 

The detected levels of PFAS at the Waialua Sugar Pump 2 water system are listed in the table below.

PFAS ChemicalPFAS Chemical AbbreviationDetected levels (ng/L) 1EPA Proposed MCL (ng/L) 1, 2
Perfluorooctanoic acidPFOA2.1 – 2.44.0
Perfluorooctanesulfonic acidPFOS3.1 – 3.74.0
Perfluorobutanesulfonic acidPFBS2.6 – 2.9see note 3
Perfluoropentanoic acidPFPeA2.5 – 2.7 

1       ng/L = nanogram per liter = parts per trillion (ppt)

2    The box left blank indicate that a level has not been set for that chemical.

3    This contaminant is considered in the proposed Hazard Index calculation. 

According to the EPA, PFAS, which have been used since the 1940’s, are fluorinated organic chemicals that have been used extensively in consumer products such as carpets, clothing, fabrics for furniture, paper packaging for food, and other materials (e.g., cookware) designed to be waterproof, stain-resistant, or non-stick. They are also a component of fire-fighting foam and have many industrial uses.

For more information on PFAS, please see https://www.epa.gov/pfas or https://health.hawaii.gov/pfas. Users may also contact their water purveyor.

This press release is issued in accordance with Hawaii Revised Statutes (HRS) Section 340E‑24(b).

Acronyms and Definitions

DOH – Hawaiʻi Department of Health, responsible for regulation and oversight of impacts to the environment and health of the people in Hawaiʻi.  This includes regulated drinking water systems.

EPA – United States Environmental Protection Agency responsible for the protection of human health and the environment on a national level.

HRS – Hawaiʻi Revised Statutes are laws enacted by the Hawaiʻi State legislature.

Hazard Index – A cumulative health risk to be considered when multiple compounds are present even if individual MCLs or EALs are met. The Health Index is the sum of the ratios of the respective contaminants. The proposed EPA requirement is to be less than 1.0 (unitless) to be in compliance.

MCL – Maximum Contaminant Level, set by EPA, is the highest level of a contaminant that is allowed in drinking water.  Proposed MCLs are not enforceable. On March 14, 2023, EPA issued proposed MCLs for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) and Maximum Contaminant Level Goals (MCLGs) for four additional PFAS compounds. Final MCLs are anticipated in late 2023, at which time these values would become enforceable legal limits and public water systems would be required to test for these chemicals. As of this news release, the final MCLs have not yet been published.

PFAS – Perfluoroalkyl and Polyfluoroalkyl substances, fluorinated organic chemicals that have been used extensively since the 1940s.

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