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Draft Finding of No Significant Impact (FONSI) - SONAR Underwater Inspection Systems (UIS)

CBP proposes to deploy underwater inspection systems (UIS) that use very high frequency (VHF, above 200 kHz) active sound navigation and ranging (SONAR) technology for demonstration, training, and operational purposes (Proposed Action) at various locations within CBP jurisdiction along the U.S. continental coastline, Hawaii, Alaska, U.S. territories, and all inland operating areas.  SONAR technology would be used in support of CBP efforts to locate, image, and classify submerged/underwater targets of interest, and to protect maritime assets and port facilities.

The U.S. Coast Guard (USCG) prepared the 2013 Programmatic Environmental Assessment (PEA) for the Nationwide Use of High Frequency and Ultra High Frequency Active SONAR Technology (November 2013) to evaluate the environmental effects of deploying the same UIS for similar uses along U.S. coastlines.  The USCG PEA fully covers the scope of CBP’s Proposed Action, alternatives, and environmental impacts. As such, CBP is adopting the USCG PEA in this Finding of No Significant Impact (FONSI) in accordance with the Council on Environmental Quality (CEQ) National Environmental Policy Act (NEPA) Implementing Regulations at 40 CFR §1506.  

Comments on the draft FONSI must be received by December 19, 2021.  Comments can be submitted to John Petrilla at: U.S. Customs and Border Protection, 24000 Avila Road, Suite 5020, Laguna Niguel, CA 92677 or by email at  When submitting via email, please reference “Underwater Inspection Systems Draft FONSI” in the subject line.  Thank you in advance for your assistance.  

Attachment Ext. Size Date
Draft FONSI-SONAR-UIS PDF 68.97 KB 11/09/2021
Last Modified: Nov 16, 2021