BWX Technologies Inc subsidiary Nuclear Fuel Services Inc (NFS) has been awarded a USD505 million contract for the downblending of 20.2 tonnes of highly enriched uranium (HEU) to low enriched uranium (LEU), the largest single downblending contract in NFS's history.

Watts Bar (Image: TVA)

NFS is to provide downblending services to the Tennessee Valley Authority (TVA) under the six-year contract, with work expected to begin in early 2019 and continue until mid-2025. The work supports the objectives of the US Department of Energy National Nuclear Security Administration's (NNS) defence programmes.

Downblending involves mixing HEU with natural uranium to make LEU, which can then be used be used as fuel in commercial reactors. The LEU can also be used for national defence purposes including the production of tritium, a key component of the USA's nuclear weapons stockpile. The isotope has a relatively short half-life of 12.3 years and decays at a rate of about 5.5% per year, so must be periodically replenished to maintain the designed capability of the weapons.

The USA's supply of tritium is produced by the irradiation of lithium-containing rods, known as tritium producing burnable absorber rods, in the core of the TVA's Watts Bar unit 1 reactor. As the tritium is used for military purposes, the reactor producing it must be fuelled by so-called unobligated LEU - that is, material that is free from peaceful use restrictions. The uranium, technology and equipment used to produce it must therefore be of US origin.

The NNSA is responsible for securing supplies of unobligated LEU for the US programme, but the USA has had no uranium enrichment capability to produce unobligated LEU since the 2013 closure of the Paducah enrichment plant. It must therefore be produced by downblending HEU from DOE's inventories.

BWXT President and CEO Rex Geveden said the contract award "speaks to the truly unique capabilities in nuclear materials processing at BWXT and edifies one of our key lines of business".

The NNSA and TVA in August announced an interagency agreement for a downblending campaign running from 2019 to 2025, with TVA providing material management and storage logistics through to 2040.

Researched and written by World Nuclear News

Date: Monday, 01 October 2018
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