Naval Computer and Telecommunications Area Master Station Eastern Pacific

Overview

The Naval Computer and Telecommunications Area Master Station Eastern Pacific is an active military installation spread across Oahu, Hawaii. It was added to the Superfund National Priorities List (NPL) in May 1994. Cleanup is organized into 12 operable units, each targeting a specific contaminated area such as transformer sites, disposal sites, gulches, and landfills. Construction is estimated to finish between September and November 2027, and the site has not yet been deleted from the NPL.

Contaminants of concern are found in soil across five operational areas. They include polychlorinated biphenyls (PCBs), metals such as lead, arsenic, chromium, copper, and vanadium, polycyclic aromatic hydrocarbons (PAHs) like benzo(a)pyrene, chlorinated dioxins and furans, and cyanide. Additional metals including aluminum, antimony, iron, manganese, and thallium were also detected. Most contaminated areas are former land disposal sites and PCB transformer locations that are no longer in use.

The Navy is leading cleanup under its Installation Restoration Program, with oversight from the U.S. EPA and the Hawaii Department of Health. Past work includes excavation and thermal desorption treatment of PCB-contaminated soil, with excavated areas backfilled with clean soil. EPA has selected "no further action" remedies for several areas, including the dump site near Building 293 and seven transformer sites, because contaminants there did not pose a threat. Five other transformer sites have long-term remedies that include land use controls to restrict how those areas can be used.

Human exposure to contamination is currently under control. EPA assessments show no unacceptable exposure pathways exist at this time. Groundwater migration is also under control, with EPA concluding that any contaminated groundwater movement is stabilized and poses no unacceptable risk to surface water. EPA will continue monitoring to keep contaminated groundwater within the original area. Physical construction is still ongoing, and the site has not yet achieved sitewide ready-for-anticipated-use status, meaning some cleanup goals affecting current or future land uses have not been fully met. The most recent five-year review was completed on September 24, 2025.

Community members with questions about the site can contact the designated Community Involvement Coordinator.