Samples were collected between May 12, 2021 and January 3, 2022. The validated data indicates heightened levels of total petroleum hydrocarbons (TPH) in both soil vapor and groundwater across multiple sites. While there are periodic detections of petroleum product in groundwater samples, at this time, there is no evidence that Board of Water Supply drinking water has been impacted.
Detections have been mostly TPH-Oil and TPH-Diesel. The Red Hill facility has been the site of multiple fuel spills going back decades. The recent detections are intermittent and do not present a clear pattern in occurrence or concentration. For instance, elevated detections of fuel products in groundwater and soil vapor monitoring in individual sampling locations may drop to normal levels and then show up again in days or weeks. The Navy stopped using its Red Hill Shaft in late November and Aiea Halawa Shaft on December 3. Turning off these pumps, combined with the BWS suspension of pumping at its Halawa well, has affected the movement of groundwater, which could, in turn, affect monitoring well data.
“We are moving forward methodically based on science to protect public health and the environment,” said Kathleen Ho, Deputy Director of Environmental Health. “While the data we have is neither complete nor conclusive, we are working with our partners to learn more and take appropriate measures to protect our water resources. People’s lives, and the health of our ecosystem are at stake, and we need more data before drawing conclusions.”
To gain a better understanding of the environmental impact, DOH is working with its partners to increase the amount of data collected and analyzed. This data will provide more sampling points, subsurface geologic information, and insight into movement of groundwater and contaminants. The Oʻahu aquifer sits on top of basalt, making it fundamentally different from aquifers found on the mainland.
DOH is also releasing new data from the Navy’s Red Hill Shaft, which reflects contamination related to the November 28 contamination of the Navy drinking water system.
“I want to emphasize that for residents of Oʻahu who are on the BWS system, the water remains safe to drink,” said Kathleen Ho. “The long-term remedy to this issue is to render the Red Hill facility safe by removing fuel from the underground storage tanks. It is imperative that the Navy comply with DOH’s order.”
Click here to view the updated data. Future reports be published regularly on Tuesday afternoon.
