The Department of Homeland Security (DHS) proposes to perform research, development, testing, and evaluation (RDT&E) of counter unmanned aircraft systems (C-UAS), and conduct operational and training activities to support existing and emerging DHS mission requirements nationwide. DHS is preparing a Programmatic Environmental Assessment (PEA) to evaluate the potential impacts associated with the Proposed Action pursuant to the National Environmental Policy Act of 1969 (NEPA; 42 USC §§ 4321 et seq.); DHS Management Directive 023-01, rev. 01 Implementation of the NEPA; and DHS Instruction Manual 023-01-001-01, rev. 01, Implementation of the NEPA.
Background
An unmanned aircraft system (UAS) is defined by the Federal Aviation Administration (FAA) as an aircraft that is operated without the possibility of direct human intervention from within or on the aircraft, and which consists of the aircraft itself and the equipment necessary for its safe and efficient operation (14 CFR Part 107). C-UAS are a system or device capable of tracking, disabling, disrupting, or seizing control of an unmanned aircraft or UAS. UAS have become a security concern due to the ease with which they can aid in intelligence gathering against public, federal, and state entities; be used to conduct crimes or thwart law enforcement efforts; and/or act as a malicious platform for delivering harmful substances, contraband, or weapons. As UAS technology advances, so too will the threats that UAS pose when used by malicious actors.
C-UAS technologies employ a variety of sensors and processes that account for or exploit the physical components of a UAS and the communications between the unmanned aerial vehicle (UAV) and the ground-based control station (GCS). C-UAS systems are primarily ground-based but may be either stationary or mobile. Stationary systems may be mounted on a tripod or affixed to a stationary location (e.g., mounted on a building), while mobile systems may be handheld or vehicle-mounted for portability, depending on the overall size and configuration of the system being used.
Within DHS and its Components, C-UAS are used for a variety of purposes to support operational missions and protect DHS facilities and assets. In addition to protecting the safety and security of DHS missions, facilities, and assets, DHS may also provide C-UAS support for mass gatherings defined as National Special Security Events (NSSE) and to State, Local, Territorial, or Tribal governments for certain Special Event Assessment Rating (SEAR) events, upon request. When an unknown UAS is identified, DHS implements a C-UAS processing chain to evaluate and respond to potential threats posed by the UAS.
The processing chain generally includes five stages: Detect, Identify, Monitor, Track, and Mitigate (DIMT-M). Only authorized personnel may operate C-UAS and undertake C-UAS actions in accordance with the DIMT-M framework. C-UAS activities may be performed at any time of day or night to respond quickly and effectively to any credible threats. If, after detecting, identifying, monitoring, and tracking the UAS, it is determined not to be a credible threat, DHS may not take any actions to counter the UAS. If a UAS is violating applicable laws or FAA regulations, but does not pose a credible threat, DHS would notify the appropriate FAA Regional Operations Center. If a UAS is determined to pose a credible threat to facilities or assets, DHS may mitigate the threat.
The first four steps in the C-UAS processing chain (i.e., Detect, Identify, Monitor, and Track) are performed by receiving and analyzing data from C-UAS sensors. C-UAS, whether stationary or mobile, generally have a detection range of up to 1.2 miles, and rely on one of four types of sensors to detect UAS: radar, passive radiofrequency (RF), electro-optical/infrared (EO/IR), or acoustic. Once a UAS has been detected and has been determined to pose a credible threat to assets or facilities, DHS would employ one of two broad types of mitigation techniques, electronic or kinetic (i.e., physical force or actions that result in direct physical impact or destruction), to complete the C-UAS processing chain.
Though DHS is not currently approved to use kinetic mitigation techniques operationally, RDT&E of kinetic mitigation would be conducted to explore operational use cases, as well as environmental, health, and safety considerations to determine appropriate kinetic capabilities for Component missions. Additionally, while C-UAS mitigation techniques generally fall into the two categories of electronic and kinetic technologies, mitigation may also be achieved by locating the UAV’s operator and having that person cease operation. Proposed Action DHS proposes to perform research, development, testing, and evaluation (RDT&E) of counter unmanned aircraft systems (C-UAS), and conduct operational and training activities to support existing and emerging DHS mission requirements nationwide (Proposed Action).
The purpose of the Proposed Action is to support RDT&E of C-UAS technologies and to deploy C-UAS in operational settings to detect, identify, monitor, track, and mitigate (DIMT-M) (passively and actively) threats posed by UAS, including across the radio frequency spectrum. The Proposed Action is needed to enhance DHS’s ability to use C-UAS technologies, monitor emerging threats, protect DHS’s missions, and defend the Nation from UAS threats and malicious activity effectively and reliably. The use of C-UAS would support existing and emerging mission requirements of the various Components within DHS and facilitate their services and strategies essential to the Nation’s security, safety, and emergency response.
Within DHS, the use and application of C-UAS are actively being researched and tested to better understand C-UAS capabilities to support DIMT-M activities. DHS conducts C-UAS activities nationwide, with some recurring in certain locations based on testing and demonstration needs: Additionally, authorized Components may use C-UAS technologies for operational use, trainings, and demonstrations nationwide, including along the southwest and northern borders.
Under the Proposed Action, DHS and its Components would continue ongoing RDT&E activities, but on a nationwide scale. The Proposed Action also includes the nationwide use and operation of C-UAS, outside of a testing environment, to conduct training and operational activities, such as law enforcement and security. The Proposed Action includes all elements related to the training, operation, maintenance, and use of C-UAS, including mitigation. This would allow DHS to continue its current testing of C-UAS while also enabling DHS and its Components to use C-UAS in an operational setting to support mission requirements.
Potential impacts for this Proposed Action would be associated with the testing, operation, and use of C-UAS, including supporting systems, and mobilization to a needed location, if applicable. All C-UAS currently in use by DHS are either ground- or vehicle-mounted. C-UAS maintenance would occur in existing DHS facilities using standard tools and materials, and in accordance with standard operating procedures for equipment maintenance.
Public Participation and Interagency Coordination
DHS is seeking stakeholder input regarding any information or potential environmental concerns associated with the Proposed Action. Additionally, DHS invite agencies with jurisdiction by law and/or special expertise with respect to the environmental issues of this Proposed Action to formally cooperate with DHS in the preparation of the PEA. Agencies that would like to request cooperating agency status should follow the instructions for submitting comments provided below.
Please provide any comments, concerns, information, studies, or other data you may have regarding the Proposed Action by April 6th, 2025 to enable us to complete this phase of the project within the scheduled timeframe. All responses will be considered for incorporation in the PEA. We look forward to and welcome your participation in this analysis.
DHS has contracted AECOM to facilitate the NEPA process. If you have comments or information relevant to the development of the PEA, please direct your correspondence to Natalie Kisak at natalie.kisak@aecom.com.