Welcome to the U.S. Navy’s website for Surveillance Towed Array Sensor System (SURTASS) Low Frequency Active (LFA) Sonar.

This website is a resource for information concerning the potential environmental effects of training and testing, and more specifically military readiness activities associated with the SURTASS LFA sonar system.

In 2019, the Department of the Navy, with the National Marine Fisheries Service (NMFS) as a cooperating agency, prepared a Supplemental Environmental Impact Statement/Supplemental Overseas Environmental Impact Statement (SEIS/SOEIS) for SURTASS LFA sonar in accordance with the National Environmental Policy Act and Executive Order 12114 The 2019 SEIS/SOEIS supported authorization by NMFS,  under the Marine Mammal Protection Act (MMPA) and its implementing regulations, to allow the incidental takes of threatened and endangered marine species under the Endangered Species Act. It is anticipated that a supplemental National Environmental Policy Act (NEPA) analysis will begin in summer 2024 to support renewal of current federal regulatory permits and authorizations that expire in August 2026.

Project Schedule and Public Involvement

Public involvement is a fundamental aspect of the NEPA process, and there are opportunities for the public to participate in the development of the SEIS/OEIS. The Navy welcomes and appreciates the public’s participation. The planned project schedule is outlined below. Please note that this schedule may change as the project progresses; in that case this page will be updated accordingly.