The Hawai‘i Department of Health (DOH) has released updated data obtained from the Navy on groundwater monitoring around the Red Hill Bulk Fuel Storage Facility.

The validated data of samples collected between May 12, 2021 and January 3, 2022, 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.

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.