The National Nuclear Security Administration (NNSA) last week gave the Y-12 National Security Complex in Tennessee the all-clear to start building a key piece of equipment needed to move uranium secondary-stage work out of the aging Building 9212 and into the under-construction Uranium Processing Facility.
The new calciner, to be built in 9212, reached its Critical Decision 2/3 milestones on Friday, a spokesperson for the semiautonomous Department of Energy nuclear weapons agency wrote Monday in an email. Critical Decision 3 is the DOE milestone that authorizes a contractor to begin construction. The calciner will turn low-enriched uranium liquid into a solid form suitable for storage.
The calciner, along with a uranium-purifying electrorefiner planned for Y-12’s Building 9215, is part of the NNSA plan to move production of nuclear-weapon secondary stages out of 9212 and into the Uranium Processing Facility (UPF). The new plant is supposed to be finished by 2025 at a cost no more than $6.5 billion.
The calciner project will cost $107.87 million to finish by September 2023, according to a Monday press release from the NNSA. The agency plans to start up the unit that year, according to its fiscal 2021 budget request. The calciner budget is about $20 million for the current fiscal 2020; the NNSA seeks $24 million for the next fiscal year, which begins Oct. 1.
The NNSA authorized construction on the calciner a few weeks later than expected. Y-12 prime Consolidated Nuclear Security, a Bechtel National-led team, turned its critical decision 2/3 package into the agency in October. At the time, the contractor said it needed startup authorization by May 11. The NNSA did not say why the milestone slipped.
In 2019, Consolidated Nuclear Security discovered that subcontractor Hicks and Ingle, of Knoxville, Tenn., made some 40 bad welds in 20 pipe spool pieces intended for the calciner. The prime kept its contractor on after the mishap, and Hicks and Ingle built replacement pipe spools for the calciner, a Y-12 spokesperson said last month.
