Frequently Asked Questions

1. What is the selected alternative?
The selected alternative (Proposed Action) is to construct, deploy, and operate and maintain a comprehensive, persistent, 360-degree Enhanced Integrated Air and Missile Defense (EIAMD) system to defend the people, infrastructure, and territory of Guam against the rapidly evolving threats of advanced cruise, ballistic, and hypersonic missile attacks from regional adversaries.

2. What is the Enhanced Integrated Air and Missile Defense system?
The system includes a combination of components from the Missile Defense Agency (MDA), the U.S. Army, and the U.S. Navy that will be integrated for air and missile defense. These components include missile defense radars, sensors, missile launchers and missile interceptors, and command and control systems.

3. Why is the Enhanced Integrated Air and Missile Defense system needed on Guam?
U.S. Indo-Pacific Command identified a requirement for a 360-degree EIAMD capability on Guam as soon as possible to address the rapid evolution of adversary missile threats. As a U.S. territory, an attack on Guam is an attack on the United States and would be met with an appropriate response.

4. What is a 360-degree missile defense coverage for Guam?
The EIAMD system will defend Guam against regional cruise, ballistic, and hypersonic missile attacks from regional adversaries. The 360-degree capability is achieved by distributing/placing missile defense components, including missile defense radars, sensors, missile launchers and missile interceptors, and command and control system, at multiple locations around the island. These integrated components will defend against simultaneous air and missile attacks against Guam.

5. Why do the Enhanced Integrated Air and Missile Defense system components need to be spread out across the island? Why can’t they be in one place?
The topography of the island of Guam and limited contiguous DoD-controlled land prevents the deployment and operation of all the required system components necessary to detect and defeat adversary missiles to be located in one central location. In addition, spreading the system components across the island increases the resilience of the overall defensive system.

6. What is the expected completion date for the Enhanced Integrated Air and Missile Defense system? How soon could we see the island and region completely defended against our adversaries?
Site preparation and construction will span approximately 10 years beginning in 2025. The EIAMD operational capability will be phased in as each site completes construction, testing, and final system checks of the installed components. Following final construction, testing, and final system-wide checks, the EIAMD system will become fully operational.

7. Is the Enhanced Integrated Air and Missile Defense system for Guam intended to defend the entire island and its population, or only important military sites?
The EIAMD system will protect the people, infrastructure, and territory of Guam from adversary missile threats.

8. What is NEPA?
NEPA – or the National Environmental Policy Act – is a U.S. law that requires federal agencies to identify and analyze potential environmental impacts of their proposed actions, and to identify mitigation measures to minimize potential impacts, before deciding whether to proceed with that action. The law encourages and facilitates public involvement to inform decision makers on actions that may affect the community or the environment, and potential mitigation measures for those actions.

9. What is an EIS?
An EIS – or Environmental Impact Statement – is a detailed document prepared for proposed actions expected to have a significant impact on the quality of the human environment. An EIS describes the proposed action and its need, any alternative actions to the proposed action, and the potential environmental impacts of the proposed action and alternatives. The EIS process begins with publication of a Notice of Intent in the Federal Register and ends with the issuance of a Record of Decision. The Record of Decision documents the decision on which action to implement and includes a discussion of mitigation and monitoring measures, if necessary. Cooperating agencies, such as the Federal Aviation Administration (FAA), may have additional decisional documents and publish a separate Record of Decision.

10. Who prepared the EIS? The MDA is the lead agency for preparing the EIS and will ensure environmental compliance and permitting for the EIAMD system, including MDA and U.S. Navy sites and assets. The U.S. Army is responsible for environmental compliance and permitting for Army sites and assets.

Due to jurisdiction or expertise, or for potentially affected operations and resources, the U.S. Army, U.S. Navy, U.S. Air Force, and FAA are cooperating agencies in the preparation and review of the EIS. Naval Facilities Engineering Systems Command, Pacific will be the executing agent for environmental compliance. MDA will have additional inputs and involvement from other federal and local agencies, as well as Joint Region Marianas and U.S. Indo-Pacific Command, and the public.

11. What impacts were analyzed in the EIS?
The MDA and cooperating agencies analyzed the potential direct and indirect impacts the Proposed Action may have on airspace management, health and safety, cultural resources, terrestrial biological resources, socioeconomics, protection of children, land use and recreation, transportation, visual quality, utilities, air quality, greenhouse gases, noise, water, and geology and soils.

12. Is MDA conducting a separate EIS for each candidate site?
No, the MDA, in coordination with the U.S. Army, U.S. Navy, U.S. Air Force, and FAA, prepared a single, consolidated EIS for all the candidate sites for the system components

13. When did the EIS process start?
The MDA published a Notice of Intent in the Federal Register, which announced the preparation of an EIS on May 5, 2023.

14. When will the EIS process be complete?
The MDA and cooperating agencies published the Final EIS in July 2025. The Record of Decision was announced in September 2025.

15. What were the steps in the EIAMD EIS process?
There are six basic steps:
1) Agency planning and development of NEPA strategy;
2) Public scoping following the publication of a Notice of Intent announcing the intent to prepare an EIS;
3) Preparation of the Draft EIS;
4) Public review and comment period following the publication of the Draft EIS Notice of Availability;
5) Preparation of the Final EIS; and
6) Preparation of the Record of Decision.

16. How can people obtain more information on the EIS process?
Information on NEPA and the public involvement process can be found on the MDA public website at www.mda.mil/system/eiamd.

The Record of Decision and the Final EIS are available on this website for download and at the following public libraries: (1) University of Guam Robert F. Kennedy Memorial Library, UOG Station, Mangilao, Guam 96913; and (2) Nieves M. Flores Memorial Library, 254 Martyr St., Agana, Guam 96910.

For more information, the public can also contact Mr. Mark Wright, MDA Public Affairs, at 571-231-8212 or by email to mda.info@mda.mil.

17. Does the public have an opportunity to provide input or comments in the EIS process?
The completion of the Final EIS follows years of data gathering, analysis, stakeholder engagement, and public involvement. The MDA and the U.S.Army held three public scoping meetings in 2023 and two Draft EIS public meetings in 2024 and obtained stakeholder input at several stages during the environmental planning process. The Final EIS includes responses to public comments received on the Draft EIS.