Top left banner Top right banner
Bottom left banner Bottom right banner



Fact Sheets

National Environmental Policy Act (NEPA) Process

Training and Testing in the HSTT Study Area

Environmental Stewardship


Welcome to the United States (U.S.) Department of the Navy's Hawaii-Southern California Training and Testing (HSTT) environmental planning website.

The HSTT website is an online resource for information concerning the potential environmental effects of training and testing (military readiness) activities that occur in the high seas areas located in the Pacific Ocean along the coast of California, in the waters around the Hawaiian Islands, and within California and Hawaii inland waters such as Navy and Civilian Ports.

The third (Phase III) comprehensive review of potential environmental effects of military readiness activities was published in October of 2018. The HSTT Environmental Impact Statement (EIS)/Overseas Environmental Impact Statement (OEIS) supported authorization by the National Marine Fisheries Service, as a cooperating agency, of incidental takes of marine mammals under the Marine Mammal Protection Act and incidental takes of threatened and endangered marine species under the Endangered Species Act.

It is anticipated that a follow-on National Environmental Policy Act (NEPA) analysis will begin in 2023 to support renewal of current federal regulatory permits and authorizations that expire in December of 2025. Registered Subscribers will receive email status updates.

Participating U.S. Navy Commands

U.S. Pacific Fleet

Protects and defends the maritime interests of the United States and its allies and partners in the Asia-Pacific region. Enhances stability, promotes maritime security and freedom of the seas, deters aggression and, when necessary, fights to win.

Naval Air Systems Command

Develops, acquires, delivers and sustains aircraft and systems with proven capability and reliability to ensure that Sailors achieve mission success.

Naval Sea Systems Command

Develops, acquires, delivers and maintains surface ships, submarines and systems that provide the right capability to Sailors.

Naval Information Warfare Systems Command

Develops, delivers and sustains information warfare capabilities and services that enable naval, joint, coalition and other national missions operating in warfighting domains from seabed to space.

Office of Naval Research

Plans, fosters and encourages scientific research that promotes future naval seapower and enhances national security.




Commander U.S. Pacific Fleet     Naval Air Systems Command     Naval Sea Systems Command     NAVWAR     Office of Naval Research Science & Technology