The US Air Force (USAF) has finalised the environmental assessment/overseas environmental assessment (EA/OEA) for the Ground-Based Strategic Deterrent (GBSD) test programme.

The service has also signed the ‘Mitigated Finding of No Significant Impact’.

According to the Air Force Global Strike Command (AFGSC), the GBSD programme is the replacement for the ageing US land-based intercontinental ballistic missile (ICBM) LGM-30 Minuteman III system.

Built by Boeing, the LGM-30 Minuteman III ICBM is used by the USAF Combat Command.

It is a vital component of the US strategic deterrent forces. The inventory is controlled by the Air Force Global Strike Command.

The USAF plans to modernise the ‘land-based leg of the nuclear triad, recapitalising its ICBM fleet’.

It also plans to upgrade the weapon system technology, supporting infrastructure, as well as command and control functions of ICBM.

AFGSC noted that the test programme-related actions would occur primarily at Hill Air Force Base (AFB) in Utah, and at Vandenberg AFB in California.

These tests will include conducting missile launches from Vandenberg AFB with flights over the Pacific Ocean in the Western Test Range.

Other test support activities would also take place at US Army Dugway Proving Ground in Utah.

AFGSC in a statement said: “The environmental assessment also includes analysis of the proposed GBSD Formal Training Unit/Schoolhouse at Vandenberg AFB.

“The GBSD and Minuteman III test demonstrations are proposed to occur at US Army Garrison–Kwajalein Atoll and within the Republic of the Marshall Islands territorial waters.

“The analysis of overseas environmental impacts is also included in the assessment. Test activities would comply with the US Army Kwajalein Atoll environmental standards.”

In February, the USAF released the draft GBSD test programme environmental assessment.