Stovepiping within the Department of Energy was responsible for the critical US shortage of helium-3, the rare isotope used in low-temperature physics, medical applications and neutron detection. The National Nuclear Security Administration (NNSA) and the Office of Science’s isotopes department failed to share information on the size of the ³He inventory or the amount of demand for the gas, according to the Government Accountability Office.

Although NNSA manages production of ³He, the isotopes office is responsible for sales and distribution of the gas. Because neither DOE office was in charge, both failed to spot the shortage developing until the inventory had been nearly exhausted, the GAO report said. From 2003 to 2009, an average of 30 000 liters of ³He was sold, but NNSA had a capacity to produce only 8000 to 10,000 L annually. As a result, inventory of ³He plunged from 260,000 L in 2003 to 31,000 L at the end of February 2011.

The GAO report, prepared for Representatives Brad Miller (D-NC) and Donna Edwards (D-MD), noted that officials from NNSA and the Office of Science told the GAO auditors they did not consider ³He to be part of their respective missions. NNSA, whose primary mission is maintaining the nuclear weapons stockpile, did not keep the Office of Science up to date on the inventory’s size because it believed the information to be classified. NNSA failed to inform the isotopes department at the Office of Science it had transferred 34,000 L of ³He—more than the total average annual demand for the gas—to the Spallation Neutron Source at Oak Ridge National Laboratory until after it was shipped. The Office of Science, for its part, failed to tell NNSA the rate at which demand for the gas was growing. Isotope department managers considered the sale of ³He to be a courtesy to NNSA, since unlike other isotopes they sell, they don’t control ³He production.

Helium-3 is a decay product of tritium, which is used in nuclear weapons. NNSA periodically extracts the ³He from tritium reservoirs to ensure that the warheads will function as they were designed. According to the GAO, NNSA believed that revealing the amount of ³He in the inventory might allow a potential adversary to calculate the number of weapons in the US nuclear arsenal. As the number of weapons dropped in line with arms control treaties, the need for tritium has plunged. At the same time, a vast new demand source for ³He came with the deployment of thousands of radiation portal monitors at US ports and border crossings and abroad to prevent the smuggling of nuclear materials. Use of the isotope in neutron detection dwarfed all others.

History of the supply crunch

The developing supply crunch was first detected in June 2008, when a contractor told the Domestic Nuclear Detection Office that it could not get enough ³He to fill its needs. DOE suspended sales of the gas three months later, even as NNSA and the Office of Science renewed a memorandum of understanding to continue their arrangement. In 2009 an interagency task force headquartered at the National Security Council ordered a halt in sales to DNDO and began to ration ³He to the other users.

The GAO found that Linde, formerly Spectra Gases, which is the sole distributor of US-origin ³He, was far better informed of the supply and demand situation than anyone at DOE. Linde operates the only US facility licensed to purify ³He of trace amounts of tritium.

The US has been holding discussions with Ontario Power Generation (OPG) about extracting ³He from tritium in storage at the Canadian utility. That tritium has been extracted from the heavy-water moderater/coolant of OPG’s 16 Canadian deuterium-uranium reactors. OPG estimates that as much as 100,000 L of ³He could be extracted from the tritium right away, with another 10,000 L becoming available annually thereafter. The US Bureau of Land Management, which operates the national helium reserve, estimates that it contains 150,000 L of ³He. Extraction could take 10 years, GAO said. A second reserve of helium in Wyoming is estimated to hold 200,000 L of ³He, according to the GAO report.

-David Kramer