DOH Releases Findings of Independent Forensic Investigation of Navy Water System
Posted on May 22, 2024 in Navy Water System Incident, NewsroomJet fuel not present in drinking water samples taken in February 2024
HONOLULU – An independent investigation by the Hawaiʻi Department of Health (DOH), confirmed that no petroleum or jet fuel compounds were detected in 15 drinking water samples collected at Joint Base Pearl Harbor-Hickam (JBPHH) and Aliamanu Military Reservation (AMR)—12 from homes at JBPHH and AMR and three from source water shafts. While the Navy’s Waiawa Shaft is the current sole source for the JBPHH and AMR drinking water systems, samples were also collected from the Navy’s ʻAiea-Hālawa and Red Hill Shafts.
The investigation was prompted by an uptrend of low-level TPH detections in late 2023. DOH employed the services of a petroleum forensic consultant to conduct the analysis. Advanced forensic techniques were used, which provided a higher level of detection than the unmodified testing methods employed by the Navy during Long-Term Monitoring (LTM).
“This report provides reassurance that no petroleum was detected in the 15 drinking water samples DOH collected,” said Deputy Director for Environmental Health Kathleen Ho. “It also shows that forensic techniques are effective in analyzing low-level—and we expect the Navy to implement forensic analysis in its future testing to provide the public with accurate data.”
Although the DOH investigation concluded that no petroleum was detected, the department does not endorse all of the conclusions drawn by the Navy in its “SWARM Team” investigation into the uptrend of TPH detections.
- DOH disagrees with the Navy’s conclusion that certain drinking water zones could not have been contaminated by the Red Hill Shaft during the November 2021 emergency. The Navy should continue to respond to complaints from zones served by its drinking water system.
- The corrective actions proposed by the Navy to account for lab error may decrease sensitivity of the detection. As such, for the purpose of its continued monitoring, the Navy should be committed to include forensic techniques whenever a detection is made.
A summary of DOH’s independent investigation is included below. Click here to read the full report.
Was there jet fuel in the samples DOH collected?
No petroleum or jet fuel compounds were detected. Forensic experts, versed in petroleum investigation, analyzed the water samples at a specialized laboratory experienced in conducting advanced testing.
Is the DOH saying there is no residual jet fuel at JBPHH/AMR?
While the testing is definitive for the locations and dates sampled, the sampling is limited to 12 homes where TPH was previously detected and the Navy’s Waiawa Shaft, ʻAiea-Hālawa Shaft, and Red Hill Shaft. While the Waiawa Shaft is the current sole source for the JBPHH and AMR drinking water systems, samples were also collected from the Navy’s ʻAiea-Hālawa and Red Hill Shafts.
As such, a generalized conclusion that there is no residual fuel for the entire base cannot be made. However, the Navy will have an opportunity to demonstrate a downtrend in the detection during the additional year of sampling. This extended monitoring will comprise of 3,500 additional tests in residences/buildings. This continued large-scale testing would be more representative of the system, and as such, better conclusions can be made.
Why doesn’t the Navy use forensic testing?
DOH’s independent investigation demonstrates the need for forensic testing at low levels of TPH detections where both non-targeted environmental and laboratory artifacts can interfere with the test results. The Hazard Evaluation and Emergency Response (HEER) Office recommends forensic testing for any detections of TPH below 200 parts per billion (ppb) to differentiate between potential petroleum (petrogenic) compounds, interferences caused by other non-petroleum (biogenic) organic compounds, and laboratory artifacts at levels typically below this value. A drawback of forensic testing is that it does require more time to conduct a sequence of progressive tests. Following regulatory comments, the Navy will incorporate forensic testing in its extended monitoring.
Did the DOH confirm that the false TPH readings were created by chlorine?
Currently, the exact chemistry that led to the high rate of TPH detections during LTM is not known. The Navy attributed the low-level TPH detections to O-terphenyl (OTP), a chemical surrogate added as part of the TPH screening test, interacting with chlorine. However, while halogenated derived compounds (attributed to disinfection treatment) were detected, it is unclear if OTP was the sole precursor responsible for “false” TPH detections, as hypothesized by the Navy. All surrogates used were able to achieve recovery within laboratory limits, meaning that OTP and other surrogates introduced in testing were detected at similar levels after the testing was complete. If OTP interacting with chlorine was the sole cause of the detections, it would be expected that it would be recovered at lower rates following the completion of the testing process.
What non-petroleum chemicals were detected?
The investigation detected the presence of non-targeted analytes (NTAs) at low levels. These detections include brominated organic compounds and tentatively identified compounds (TIC) in the samples from the homes, but not detected from the source water shafts. Naturally occurring biogenic compounds like organic acids were found in the source water shaft samples. While the NTAs are not fuel related, further testing is underway to characterize the potential origin and chemical composition of these detected compounds. A supplemental report on the additional testing will be forthcoming.
While the test employed in this instance in the LTM, EPA Method 8015D, is a conventional laboratory technique for testing water samples for petroleum hydrocarbons, it was not designed to identify specific chemicals, such as JP-5 jet fuel, in drinking water. Additionally, conventional TPH methods are tools used for gross contamination conditions in the parts per million. Applying the same screening tools to low detections in the parts per billion prominently introduces background interference, which could create false TPH detections at the levels being tested for in the LTM. In recognition of this, the investigation used supplemental methods and modifications to further evaluate drinking water samples for the presence of petroleum hydrocarbons and other chemicals in the post-flushed drinking water environment.
TPH testing is one of many tests that inform DOH’s multiple lines of evidence approach, which considers more than 40 different compounds and screening parameters. DOH evaluates these different parameters to guide environmental assessment and remediation.
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