Environmental Investigation and Remediation

• Overview
• Environmental Monitoring
  • Monitoring Well Network
  • Monitoring Data
• Investigation and Remediation
  • Drinking Water System Recovery
  • Red Hill Shaft Recovery
  • Soil Contamination Remediation
  • Groundwater Aquifer Investigation
  • Future Remediation Actions
• Documents, Correspondence, Reports and Data

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Overview

This webpage provides information about work the Navy is required to perform to investigate and clean up contaminated soil and water from all historic fuel releases from the Red Hill Bulk Fuel Storage Facility, including the May 6, 2021 and November 20, 2021 fuel releases. This work is required under the 2023 Administrative Consent Order and included in Phase II Closure. Information about previous work to address Red Hill facility fuel releases that occurred prior to 2021 can be found on our 2015 Administrative Order on Consent page.

Efforts to clean up contamination resulting from Red Hill fuel releases in 2021 are underway and are required per Hawai'i state law and the 2023 Administrative Consent Order. Environmental monitoring of soil, soil vapor, surface water, drinking water and groundwater provide information about the nature, location, and concentrations of contaminants in the environment over time to understand the extent of contamination, inform remediation decisions, protect water resources, and restore the aquifer. This page provides up-to-date information on current efforts to clean up the contamination from Red Hill fuel releases.

Environmental Monitoring

The Navy is required to collect environmental data to satisfy environmental monitoring requirements defined under the 2015 Red Hill Administrative Order of Consent (AOC) and under State of Hawai'i laws for environmental cleanup. Navy is also required to install new groundwater monitoring wells to expand the number of locations where groundwater data is collected.

Monitoring Well Network

The Navy is required to install groundwater monitoring wells in the vicinity of the Red Hill Bulk Fuel Storage Facility to identify and track possible contamination migration from the facility. Information obtained from the groundwater monitoring wells can improve our understanding of how contamination moves in groundwater and through complex geologic structures so EPA and the Hawai'i Department of Health (DOH) can identify potential threats to drinking water.

Currently, there are 23 Navy-installed monitoring wells which include wells located at the Red Hill facility and in the vicinity of the facility. In 2022, the Navy submitted a work plan to install up to 10 additional monitoring wells. Other entities, such as the Honolulu Board of Water Supply, have installed monitoring wells in the area and plan to install more.

Additional information about the Navy’s work to install monitoring wells can be reviewed on the Groundwater Monitoring at Red Hill webpage.

Monitoring Data

The Navy is required to take samples of soil, soil vapor, groundwater, drinking water, and surface water to characterize the nature and extent of Red Hill facility fuel releases. Monitoring data helps regulatory agencies track water quality over time to better understand contaminant migration and the effectiveness of remediation approaches.

The Red Hill Administrative Order on Consent requires the Navy to take soil vapor samples on a monthly basis and groundwater samples on a quarterly basis. Following the 2021 fuel releases, the State of Hawai'i Department of Health (DOH) required the Navy to take weekly samples of soil vapor and groundwater. Furthermore, the Navy is required to conduct extensive testing of the drinking water system.

Groundwater and soil vapor monitoring data is currently posted on the DOH website:

• Release Monitoring Data (Released Weekly)
• Technical Documents for Red Hill

Information about drinking water system recovery and sampling program can be found at Drinking Water System Compliance at Joint Base Pearl Harbor-Hickam.

Investigation and Remediation

The Red Hill facility fuel spills in 2021 released fuel within the facility tunnel system, onto soil located outside of the Red Hill facility, into the Red Hill drinking water shaft, and into the groundwater aquifer. This webpage will provide updates on investigation and remediation activities. The Navy is currently cleaning up contaminated soil and removing jet fuel and associated contaminants from Red Hill Shaft. In addition, the Navy is conducting environmental investigations in several areas to identify more options for cleaning up contamination caused by Red Hill fuel releases.

Drinking Water System Recovery

The removal of fuel from the Joint Base Pearl Harbor-Hickam (JBPHH) Drinking Water system took place between December 2021 and March 2022 and concluded when the DOH lifted the JBPHH Drinking Water System Health Advisory.

Information about the drinking water system recovery efforts can be found on our Drinking Water System Compliance at Joint Base Pearl Harbor-Hickam page, DOH’s Navy Water System Incident webpage, and the Navy’s Joint Base Pearl Harbor Hickam Water Updates webpage.

For a period of 24 months immediately following the drinking water incident, the Navy is required to conduct drinking water system sampling to ensure that there is no remaining contamination in the drinking water system. For information about the Long-Term Monitoring program, see the June 2022 Drinking Water Long Term Monitoring Plan (pdf).

For updates on the Navy’s Long-Term Monitoring program, see the Navy’s Joint Base Peral Harbor Hickam Water Updates News webpage.

Red Hill Shaft Recovery

The Red Hill Shaft is one of three wells that pulls water from the groundwater aquifer to provide water for the Joint Base Pearl Harbor-Hickam drinking water system. On November 20, 2021, a Red Hill facility fuel release contaminated the Red Hill Shaft with jet fuel.

In January 2022, the Navy, EPA and DOH signed the Red Hill Shaft Recovery and Monitoring Plan which established the plan for pumping and treating water from Red Hill Shaft to remove contamination. The Navy installed a hybrid zeolite-granular activated carbon treatment system near the Red Hill Shaft, which is pumping approximately 5,000,000 gallons of water a day through the treatment system and then discharging the treated water into Halawa stream. Water quality is sampled before and after treatment to evaluate the effectiveness of the treatment system and to ensure that water discharged into Halawa stream meets water quality standards.

Soil Contamination Remediation

The November 20, 2021, Red Hill fuel release occurred near an exterior entrance to the Red Hill facility, called Adit 3. During the release, fuel migrated from the tunnel system outside of the facility through a water drainage pipeline and into a leach tank and leach field outside of Adit 3. The Navy is excavating the leach tank and contaminated soil in the area to remove contamination from the environment.

Groundwater Aquifer Investigation

Monitoring data show that fuel releases from the Red Hill facility have contaminated the groundwater aquifer, which is located 100 feet below the Red Hill facility. EPA and DOH are conducting analyses to better understand the impacts of fuel releases to the aquifer and to evaluate risk to drinking water resources.

Monitoring data following the May and November 2021 releases show that the fuel releases migrated away from the facility through the subsurface geology into the groundwater aquifer. Concentrations of fuel in the immediate area of the facility were high following the 2021 releases and concentrations have been steadily declining over time. EPA and DOH are working with water resource agencies to assess the condition of the aquifer, evaluate the impacts of pumping and treating water from Red Hill Shaft, and understand if there are potential threats from these releases to drinking water supplies in the area.

EPA and DOH gave a presentation on the status of groundwater aquifer contamination at the May 13, 2022 Fuel Tank Advisory Committee meeting.

Future Remediation Actions

The Navy is conducting investigations to inform future remediation actions. EPA will post new information about investigative work to this webpage as it becomes available.

• Related Content: EPA Review and Approval of Deep SVE Pilot Study (pdf)

Documents, Correspondence, Reports and Data

• Final EPA Comments on April 2025 Red Hill Bulk Fuel Storage Facility Site Assessment Work Plan (pdf) (171.32 KB, June 5, 2025)
  Final EPA comments on the Red Hill Bulk Fuel Storage Facility Closure Plan, Supplement 3, Phase 1 site assessment work plan. The objective of the phase 1 closure site assessment is to measure for “the presence of a release where contamination is most likely to be present at an underground storage tank (UST) site.
• EPA Response to Honolulu Board of Water Supply Request to Attend Groundwater Flow Modeling Workshop (pdf) (145.82 KB, May 15, 2025)
  EPA response to April 25, 2025 Honolulu Board of Water Supply letter requesting to attend the May 28-29, 2025, in-person Red Hill groundwater flow modeling workshop.
• EPA Letter: Review of Site Assessment Pilot Study (pdf) (166.92 KB, March 21, 2025)
  EPA letter to Navy documenting review of the Draft Independent Data Collection in Support of Site Assessment Pilot Study, Red Hill Bulk Fuel Storage Facility, Joint Base Pearl Harbor Hickam, Hawaii. EPA requests that by May 1, 2025, the Navy submit a revised Site Assessment Work Plan to implement full scale multiple line of evidence site assessment.
• EPA Letter: Review of Navy’s Shallow SVE Pilot Study (pdf) (222.54 KB, March 7, 2025)
  EPA letter to Navy documenting review of the Draft Shallow Soil Vapor Extraction (SVE) Pilot Study Report, Red Hill Bulk Fuel Storage Facility, Joint Base Pearl Harbor Hickam, Hawaii. The pilot study was conducted to determine the performance of shallow SVE beneath Adit 3 to remediate the November 2021 release of JP-5. EPA recommends evaluation of alternative effective remedial options and submittal of a technology evaluation by April 21, 2025.
• EPA Letter: Request to Collect PFAS Groundwater Samples (pdf) (146.54 KB, February 19, 2025)
  EPA letter to the Navy requesting the temporary wells in Adit 3 be added as part of the second quarter PFAS sampling event at Red Hill Bulk Fuel Facility, Joint Base Pearl Harbor Hickam, Hawaii.
• EPA Letter: Review of Navy's Draft Groundwater Model Report dated September 24, 2024 (revised September 26, 2024) (pdf) (1.83 MB, February 18, 2025)
  EPA comment letter to the Navy regarding the groundwater flow model (GWFM). The GWFM will be used in developing an accurate, functional model of groundwater flow and contaminant transport. The GWFM is one of many lines of evidence used to support decisions and will be updated as site investigations are complete. Includes Comments on “Groundwater Model Report, Red Hill Bulk Fuel Storage Facility” (September 26, 2024) and Accompanying Groundwater Model Files.
• EPA Letter: Review and Approval of Deep SVE Pilot Study (pdf) (172.73 KB, February 14, 2025)
  EPA letter to Navy concerning EPA review and approval of Draft Deep Soil Vapor Extraction Pilot Study Work Plan, Red Hill Bulk Fuel Storage Facility, Joint Base Pearl Harbor Hickam, Hawaii, dated February 23, 2023 (revised August 2, 2024). The data from the pilot study will be used to support selection of long-term remedial options.
• EPA Letter: Request for Submittal of a Groundwater Monitoring Plan (pdf) (1.06 MB, December 23, 2024)
  EPA letter to Navy requesting submittal of a groundwater monitoring plan by March 3, 2025, pursuant to ACO as Supplement 5 to the Phase 2 Closure Review plan.