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Category Archives: Nuclear Materials

Blue Topaz — The Irradiated Gemstone

Maureen Conley
Public Affairs Officer

There are a lot of great things about having a November birthday. The heat of summer is over but winter hasn’t set in so the weather can be magnificent. When the leaves are changing, the landscape is even more beautiful than in spring. It is the month of football, first frosts, harvesting the last of the summer vegetable garden, and my favorite holiday, Thanksgiving. But the one thing I never liked about my November birthday was my birthstone—topaz.

topaz 1Orange is just not my favorite color. I was always jealous of my family members, whose stones were so much prettier—amethysts in February, diamonds in April, and sapphires in September. Then one year I received as a gift some earrings with a beautiful blue stone. That was my introduction to blue topaz.

I was so happy to discover there was an alternative to the traditional orange topaz, I never thought to wonder what was behind the blue color. I figured topaz just came in blue, too.

Well it turns out blue topaz can be found in nature but it is very rare. Most blue topaz on the market has been exposed to radiation.

This is no cause for alarm. Irradiated gemstones are not harmful. Because they may be slightly radioactive immediately after their treatment, the NRC regulates the distribution of these products to ensure public health is protected. Any measureable radiation decays away within a couple months. Treated gemstones are set aside and are not sold until the radioactivity falls far below levels that can impact public health.

Distributors of irradiated gemstones must have an NRC license, which requires them to do radiological surveys before selling the gems. Their sophisticated instruments can detect very low levels of radiation. Once the radiation is low enough, no further licensing is required.

topaz 1Topaz is not the only gemstone treated with radiation to change its color. Diamonds, pearls and other gemstones are sometimes irradiated to change their color. In general, the longer stones are exposed to radiation, the deeper and more attractive the color.

Incidentally, not all radiation treatments applied to gemstones make them radioactive. If they are bombarded with neutrons, as in a nuclear reactor or accelerator, trace elements in the stones can become “activated” or radioactive. But gemstones can also be treated using gamma radiation (high-energy photons), which does not make them radioactive.

If your holiday shopping list includes jewelry this year, don’t be afraid of irradiated gemstones. The NRC license ensures they don’t reach the market until they are completely safe.

Seeing Clearly Through the Cloud – Assessing a Leak at Honeywell

Joey Ledford
Public Affairs Officer
Region II

 

The sound of alarms during the evening of Oct. 26 at the Honeywell Metropolis Works alerted workers and those living closest to the Metropolis, Ill., site that something out of the ordinary had occurred.

Honeywell MetropolisThe plant, a fixture in the southern Illinois river town since 1958, is the nation’s only uranium conversion plant. It converts raw uranium, or yellowcake, into uranium hexafluoride, or UF6, which is enriched at other facilities into fuel for commercial nuclear power plants.

That Sunday evening, Honeywell experienced a leak of UF6. The leak occurred in a cold trap inside the Feed Materials Building. (A cold trap is a large tank where raw UF6 accumulates so it can be cooled and solidified and later heated and drained during normal plant operations.) The leak occurred while the cold trap was heated and was being drained.

An operator put on a respirator and confirmed the leak at 7:24 p.m. local time. Plant emergency responders were dispatched to shut down operations and account for all personnel. Honeywell declared a “plant emergency,” but did not declare an “Alert,” the lowest NRC emergency classification for fuel facilities. Honeywell advised the NRC the cold trap was isolated, vacuum devices were being used to collect leakage, and the material in the device was cooling by 8:15 p.m.

 No one was injured and Honeywell declared “all clear” status at 2:16 a.m. Monday.

People outside the plant reported that a cloud was visible, coming from the building even before mitigation spray towers were activated. Those towers generate gigantic streams of water and water vapor into the air inside and outside the plant, and contributed to clouds that were seen after they were activated.

The NRC quickly dispatched a senior fuel facilities inspector to Honeywell to independently assess what had occurred and how Honeywell had responded. Another inspector later travelled to the facility to gather more information.

After reviewing records, interviewing Honeywell employees and examining the affected areas, the NRC has reached a number of preliminary conclusions:

  • The leaking UF6 vaporized and interacted with moisture inside the Feed Building, which converted it into UO2F2 (a solid form of uranyl fluoride, a yellow powder).
  • The uranyl fluoride was contained within the Feed Building and settled within a few feet of the cold trap leak.
  • The chemical conversion process also produced hydrogen fluoride gas, some of which was visible emanating from the building.
  • The mitigating sprays outside the building were aimed at the windows in an effort to keep the hydrogen fluoride from getting offsite.
  • Honeywell implemented their emergency plan, assessing the event and taking the actions spelled out in the plan, including stopping the leak.
  • A potential violation was identified related to the emergency classification of the event and remains under agency review.
  • The hydrogen fluoride gas that left the building had no health effects for workers or nearby residents.

Honeywell plant management has agreed to the terms of a Confirmatory Action Letter issued by the NRC to not restart the facility until the NRC is satisfied that the company has appropriately addressed the emergency classification issues raised during and after the event. Honeywell has also agreed to a number of corrective actions, including revised training and emergency procedures. The NRC is monitoring an emergency exercise at Honeywell to ensure that corrective measures are in place.

The NRC will remain vigilant and will closely inspect the corrective actions made by Honeywell this week under the CAL. As well, the NRC will consider potential enforcement actions stemming from the event.

Update: You can read the latest Preliminary Notification here.

REFRESH: Do Not Fear Your Smoke Detector – It Could Save Your Life

Maureen Conley
Public Affairs Officer

refresh leafWe sometimes get calls from people worried about radiation from smoke detectors in their homes. There are many reasons why the public need not fear these products.

Ionization chamber smoke detectors contain very small amounts of nuclear material. They might use americium-241, radium-226 or nickel-63. These products detect fires early and can save lives. [We explained how smoke detectors work in greater detail in an earlier blog post.]

The Atomic Energy Commission granted the first license to distribute smoke detectors in 1963. These early models were used mainly in factories, public buildings and warehouses. In 1969, the AEC allowed homeowners to use smoke detectors without the need for a license. Their use in homes expanded in the early 1970s. The NRC took over from the AEC in 1975.

Makers and distributors of smoke detectors must get a license from the NRC. They must show that the smoke detector meets our health, safety and labeling requirements.

smokedetectornewMost smoke detectors sold today use 1 microcurie or less of Am-241. They are very safe. A 2001 study found people living in a home with two of these units receive less than 0.002 millirems of radiation dose each year. That is about the dose from space and the earth that an East Coast resident receives in 12 hours. Denver residents receive that dose in about three hours. These doses are part of what is known as “background radiation.”

The radioactive source in the smoke detector is between two layers of metal and sealed inside the ionization chamber. The seal can only be broken by the deliberate use of force, which obviously we discourage. Still, even then it would result in only a small radiation dose. The foil does not break down over time. In a fire, the source would release less than 0.1 percent of its radioactivity. It’s important to understand that none of the sources used in smoke detectors can make anything else radioactive.

What about disposing of smoke detectors? A 1979 analysis looked at the annual dose from normal use and disposal of Am-241 smoke detectors. The study used actual data and assumptions that would overstate the risk. It allowed the NRC to conclude that 10 million unwanted smoke detectors each year can be safely put in the trash.

The 2001 study looked at doses from misuse. It found that a teacher who removed an americium source from a smoke detector and stored it in the classroom could receive 0.009 millirems per year. If the teacher used the source in classroom demonstrations, handling it for 10 hours each year would give less than a 0.001 mrem dose. A person who swallowed the source would receive a 600 mrem dose while it was passing through the body.

I hope this information allays concerns. Unless you remove and swallow the source, your dose from a smoke detector could not be distinguished from what you get throughout your day. And that smoke detector could save your life.

 REFRESH is an occasional series during which we revisit previous blog posts. This originally ran on June 11, 2013. We are rerunning now in honor of Fire Prevention Week. According to the National Fire Protection Association, the week was established to commemorate the Great Chicago Fire, which killed more than 250 people, left 100,000 homeless, destroyed more than 17,400 structures and burned more than 2,000 acres. This year’s theme is Smoke Alarms Save Lives: Test Yours Every Month.

 

NRC Joins Five Other Agencies in Addressing Uranium Contamination on the Navajo Nation

Dominick Orlando
Senior Project Manager

 

Navajo coverLast year, after five years of work to reduce risks from uranium contamination on territory that is part of the Navajo Nation, the NRC, along with four other federal agencies, reported on our progress to Congress. This week, the five federal agencies issued a plan that spells out how we’ll continue coordinating that work for the next five years.

 The agencies’ second Five-Year Plan builds on lessons learned from the first five years. It reflects new information and defines the next steps to address the most significant risks to human health and the environment. The new plan commits us to working together to reduce these risks and find long-term solutions.

 In October 2007, Congress asked the agencies to develop a plan to address the contamination on Navajo land, which dates back to the 1940s when uranium was in high demand. The Navajo Nation had large uranium deposits but regulations were not what they are today and mining companies left extensive contamination requiring cleanup. Legislation and new regulatory provisions were put in place to address these issues.

 The 2013 report capped off a five-year program the agencies conducted, in consultation with Navajo and Hopi tribal officials, to address uranium contamination on their land. Part of this work was government-to-government consultations with the Navajo.

 The program was a joint effort among EPA, the NRC, the Department of Energy, the Bureau of Indian Affairs, the Centers for Disease Control and the Indian Health Service. It focused on collecting data, identifying the most imminent risks, and addressing contaminated structures, water supplies, mills, dumps, and mines with the highest levels of radiation. We also learned more about the scope of the problem and the work that still remains.

 The NRC’s role is to oversee the work done by DOE, which is the long-term custodian for three sites storing uranium mill tailings—a sandy waste left over from processing uranium—and one former processing site. We do that by reviewing and, if acceptable, concurring on DOE’s plans to clean up contaminated groundwater, visiting the sites to evaluate how DOE is performing long-term care activities, and reviewing DOE’s performance and environmental reports.

 We will work closely with EPA, DOE, the New Mexico Environment Department, and the Navajo during the cleanup of the Northeast Church Rock site—which EPA and Navajo officials identified as the highest priority site for cleanup. The NRC will also be part of outreach activities detailed in the plan, including participating in stakeholder workshops and contributing, as appropriate, to educational and public information activities.

 Five years from now, we look forward to being able to say that with close coordination among all the parties, we have continued to make major progress in addressing concerns about uranium contamination.

NRC’s Materials and Waste Management Programs Coming Back Under One Roof

Chris Miller
Merge Coordinator and Director of Intergovernmental Liaison and Rulemaking

 

When Congress created the NRC in 1974, it established three specific offices within the agency. One of them was the Office of Nuclear Material Safety and Safeguards, or “NMSS” in NRC shorthand. This office was charged with regulating nuclear materials and the facilities associated with processing, transporting and handling them.

fuelcyclediagramThis charge was, and is, broad. The NRC’s materials and waste management programs cover facilities that use radioisotopes to diagnose and treat illnesses; devices such as radiography cameras and nuclear gauges; and decommissioning and environmental remediation. It also includes nuclear waste disposal and all phases of the nuclear fuel cycle, from uranium recovery to enrichment to fuel manufacture to spent fuel storage and transportation.

And there’s more. The program also does environmental reviews and oversees 37 Agreement States, which have assumed regulatory authority over nuclear materials, and maintains relationships with states, local governments, federal agencies and Native American Tribal organizations.

As with all organizations, the NRC’s workload has ebbed and flowed in response to a multitude of factors. Over the years, NMSS went through several structural changes to address its workload changes. In 2006, NMSS was gearing up for an increase in licensing activity related to the processing, storage and disposal of spent nuclear fuel. At the same time, the Agreement State program was growing, requiring additional coordination with the states—a function then housed in a separate Office of State and Tribal Programs.

To meet these changes and ensure effectiveness, the NRC restructured NMSS. Some of its programs were moved, including the state and tribal programs, into the new Office of Federal and State Materials and Environmental Management Programs (FSME). NMSS retained fuel cycle facilities, high-level waste disposal, spent fuel storage, and radioactive material transportation. FSME was responsible for regulating industrial, commercial, and medical uses of radioactive materials and uranium recovery activities. It also handled the decommissioning of previously operating nuclear facilities and power plants.

The NRC’s materials and waste management workload has now shifted again. At the same time, the agency is exploring ways to reduce overhead costs and improve the ratio of staff to management.

So, NRC staff launched a working group last fall to review the organizational structure of the NRC’s materials and waste management programs. With the focus shifting to long-term waste storage and disposal strategies, and an increasing number of nuclear plants moving to decommissioning, the group recommended merging FSME’s programs back into NMSS.

NRC’s Commissioners approved that proposal last week, and the merger of the two offices will be effective October 5. We think this new structure will better enable us to meet future challenges. It will improve internal coordination, balance our workload and provide greater flexibility to respond to a dynamic environment.

Current work, functions and responsibilities at the staff level will be largely unchanged. The management structure will realign into fewer divisions, with fewer managers.

In their direction to the staff, the Commissioners asked for careful monitoring of the changes and a full review after one year. We fully expect these changes to improve our communications both inside and outside of the agency, and provide for greater efficiency and flexibility going forward.

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