Welcome
Welcome to the United States (U.S.) Department of the Navy's Hawaii-California Training and Testing (HCTT) environmental planning website.
This website is an online resource for information on the preparation of the Environmental Impact Statement/Overseas Environmental Impact Statement (EIS/OEIS) to assess potential environmental effects associated with the Proposed Action to conduct at-sea military readiness activities within the HCTT Study Area (referred to as the “Study Area”). To meet training and testing requirements, the Department of the Navy (Navy) (including both the U.S. Navy and the U.S. Marine Corps), as the lead agency, jointly with the U.S. Coast Guard, U.S. Army, and U.S. Air Force, has prepared a Draft EIS/OEIS, which is currently available for public review and comment through Feb. 11, 2025. The Draft EIS/OEIS includes an analysis of the potential environmental effects associated with conducting at-sea training and testing activities, and modernization and sustainment of ranges (collectively referred to as “military readiness activities”) within the HCTT Study Area.
The development of the EIS/OEIS will help the Navy and other U.S. military services meet their environmental compliance requirements, while ensuring military readiness by:
- Supporting current and future training and testing requirements
- Allowing training and testing over greater distances, as larger areas are needed to train and test with new weapons required for countering new threats
- Supporting increased training with unmanned systems
- Increasing flexibility in conducting training and testing activities
- Supporting modernizing and sustaining range capabilities
- Updating environmental analyses using the best available science and analytical methods
- Supporting Marine Mammal Protection Act and Endangered Species Act consultations for the reissuance of federal regulatory permits and authorizations within the Study Area.
The Draft EIS/OEIS includes an analysis of at-sea military readiness activities using new information, including an updated acoustic analysis, updated marine mammal density data, and evolving and emergent best available science. Proposed military readiness activities are similar to those analyzed in the 2018 Hawaii-Southern California Training and Testing (HSTT) EIS/OEIS (“Phase III” analysis) and the at-sea activities in the 2022 Point Mugu Sea Range (PMSR) EIS/OEIS and are consistent with activities conducted off Hawaii and California for more than 80 years. Training and testing activities that include the use of active sonar, explosives, or other sources of underwater sound would employ mitigation measures intended to reduce or avoid adverse effects on marine species.
The military services are seeking the issuance of regulatory permits and authorizations under the Marine Mammal Protection Act and the Endangered Species Act to support at-sea military readiness activities within the Study Area, beginning in December 2025. Current Marine Mammal Protection Act permits will expire in December 2025 for the HSTT EIS/OEIS and in July 2029 for the PMSR EIS/OEIS. The National Marine Fisheries Service (NMFS) is a cooperating agency in the preparation of the EIS/OEIS. In the rule-making process, NMFS will consider the potential effects of the Proposed Action on the marine environment. The EIS/OEIS will support NMFS’ rule-making process to issue MMPA authorizations.
Additional project information can be found in the project overview video and Project Materials page.