WASHINGTON – The life-extension program for the B61-12 atomic bomb will cost just over $8.25 billion, according to a new estimate from the National Nuclear Security Administration (NNSA).

The new cost estimate was completed over the summer as the agency prepared to enter the production-engineering phase of the program. The baseline cost of the program is $7.605 billion, with an additional $648 million in "funds leveraged from other NNSA programs for technology and manufacturing readiness," according to an agency statement – money that has common applications across multiple weapon systems.

That cost does not include the estimated $1.3 billion that the Department of Defense plans to spend on developing and procuring tailkits for the weapons. With that included, the total cost for the program sits at roughly $9.5 billion.

The NNSA is a semi-autonomous department within the Department of Energy. While the Defense Department manages the delivery systems of the nuclear force — ships, planes and missiles — NNSA has oversight over the development, maintenance and disposal of nuclear warheads.

The agency is perusing a modernization plan known as the "3+2 Strategy," under which the NNSA is consolidating the American arsenal of warheads into five variants. The five ballistic-missile warheads now in service are being consolidated into three new interoperable warheads known as the IW-1, IW-2, and IW-3, while the five bomb and cruise-missile warhead types are being consolidated into two replacement warhead designs, the W80-4 and the B61-12.

The B61-12 replaces the B61-3, -4, -7 and -10 variants, in a move that proponents say will both update aging parts of the weapons and drive down costs for upkeep.

"The B61-12 LEP is the most complex B61-12 activity the nuclear security enterprise has undertaken in more than 20 years," the agency said in a statement. "This weapon plays a critical role in national security and directly supports President Obama’s directive to maintain a safe, secure, and effective nuclear deterrent, while reducing the size of the nuclear stockpile."

Kingston Reif, with the Arms Control Association, said the fact that the cost estimate has stayed within a 2013 range suggests NNSA's leadership does not foresee major problems in executing the life extension going forward. That 2013 cost estimate ranged between $7.3 and $9.6 billion.

Reif also notes that the estimate is lower than a 2012 cost estimate from the Pentagon’s CAPE office, in part due to the fact that first production is slated for 2020 and not, as CAPE expected, 2022. He believes the program has cost NNSA about $2 billion through fiscal year 2016.

The Pentagon is seeking a sweeping recapitalization of its nuclear systems. In addition to the 3+2 plan, the DoD will spend the 2020s bringing online a new nuclear submarine design, replacing the Minuteman III intercontinental ballistic missiles, and producing the B-21 Raider bomber.

During a cross-country trip in late September, Secretary of Defense Ash Carter made his case for the expensive and wide-ranging upgrades that are required to modernize the nuclear triad.

"If we don’t replace these systems, quite simply they will age even more, and become unsafe, unreliable, and ineffective. The fact is, most of our nuclear weapon delivery systems have already been extended decades beyond their original expected service lives," Carter said Sept. 26. "So it’s not a choice between replacing these platforms or keeping them. … It’s really a choice between replacing them or losing them. That would mean losing confidence in our ability to deter, which we can’t afford in today’s volatile security environment."

The nonproliferation community has targeted the Long Range Stand-Off (LRSO) cruise missile replacement as one arm of the nuclear force that could be potentially cut, something that was given a big boost when audio emerged last month of presidential frontrunner Hillary Clinton expressing concerns about the program.

"The progress on the B61 mod 12 also reinforces the excessive redundancy associated with planning to buy a new fleet of nuclear air-launched cruise missiles and refurbish the warhead that will arm the missile fleet, an effort estimated to cost roughly $20-$25 billion," Reif said.

Aaron Mehta was deputy editor and senior Pentagon correspondent for Defense News, covering policy, strategy and acquisition at the highest levels of the Defense Department and its international partners.

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