Archive Preserves At-Risk Samples

Posted: July 22, 2013 - 3:21pm | Y-12 Report | Volume 10, Issue 1 | 2013

A sample of the 1940s material from the Shinkolobwe Mine in the Katanga province of the Belgian Congo.

As uranium’s usefulness became apparent leading up to World War II, the demand for uranium ore supplies for research and development escalated. The U.S. sought to acquire uranium in North America during the early 1940s, but the amount, and quality, of ores was limited. Thus, most of the country’s initial uranium ores, including the uranium that was processed at Y‑12 and used in the first atomic bomb, likely came from the Shinkolobwe Mine, in the Katanga province of the Belgian Congo.

To ensure that specimens of these 1940s belgian Congo materials and other legacy uranium materials are preserved today, the U.S. needs a secure site for their collection. Enter the National Uranium Materials Archive, housed at Y‑12 as part of the U.S. government’s Nuclear Materials Information Program.

“Department of Energy Headquarters looked at who had the best capabilities, visited some sites and decided Y‑12 made the most sense for the uranium archive,” said Jim Placke, Y‑12 Global Security Technologies manager, noting that a similar plutonium archive was established at Los Alamos National Laboratory. “We have the expertise, and we handle and protect uranium every day.”

With the physical space, stringent guidelines and operating procedures established, Y‑12 began to populate the archive. To ensure funds are used efficiently, a special selection committee identifies at-risk samples and approves or denies nominated materials.

“We had to identify materials that were at risk of being lost through highly enriched uranium disposition programs, for example,” said Susan Turner, Y‑12 program manager. “National labs and other secure sites may have small amounts of significant, useful materials. We locate those before they’re recycled or used.”

As those samples are located, Y‑12 continues to build up the archive, which operates on the same principles as a well-organized baseball card collection. In lieu of plastic sleeves and shoeboxes, each uranium sample is stored in a small glass vial within a larger, approved Y‑12 container. The uranium is generally stored as a metal or oxide to comply with Y‑12’s Safety basis, which identifies hazards for nuclear facilities and establishes controls to prevent or mitigate the consequences.

“Archive materials are stored for the short term in containers in various buildings while being handled or processed, then placed in long-term storage,” said Turner. “We store them now while available so we can perform analyses when requested.”

When a request is made, a sample is taken from its “shoebox,” prepared in a clean room to avoid introducing any new contaminants and then analyzed. “A sample is typically characterized for isotopic content and impurities,” Turner said. “This may include wet chemistry for sample prep and the use of mass spectrometry and inductively coupled plasma techniques.”

The analyses are used for forensic comparison to materials found outside of regulatory control, including those associated with nuclear terrorism or smuggling events. Ultimately, the global danger of weapons of mass destruction is reduced by Y‑12’s knowledge of proliferation-sensitive materials.

“In addition to Defense Programs, the core missions of the Department of Energy and the National Nuclear Security Administration are to prevent proliferation and perform emergency response,” Turner noted. “Y‑12 has the mission and the capability to respond to nuclear material incidents, and this archive strengthens national security through our stewardship of nuclear materials.”