ENS 57016
ENS Event | |
|---|---|
06:00 Mar 7, 2024 | |
| Title | Damaged Gauges |
| Event Description | The following was received from the Illinois Emergency Management Agency (the Agency) via email:
On March 7, 2024, the Agency was notified of equipment damage at Alton Steel in Alton, IL, that exposed two sealed radioactive sources. The licensee reported that molten steel flowed over Berthold Technologies source housings (source housing serial numbers 1197-10-21 and 601-05-12) and, despite trying to cool the steel, it damaged the source housings and exposed the sources. The Berthold Technologies sources are Co-60 and have an activity of 2.3 mCi each (source serial numbers 1200-10-21 and 600-05-12). The sources were removed from the housings by a licensed service provider and placed in secured storage. Leak tests are pending. The licensee determined there were no exposures to any personnel and that the incident does not pose a risk to any members of the public. Licensee surveys indicated no contamination, and radiation levels from these sources were comparable to those from an undamaged source. The Agency plans to conduct a reactionary inspection to verify the lack of contamination/exposure and accountability of licensed materials. This is a reportable event in accordance with 32 Ill. Adm. Code 340.1220(c)(2). Illinois Item No.: IL240008
[On 3/8/24], another email update was received in which Alton Steels licensed contractor advised another portion of the source rod had been located and was actively being cut from the molten steel. A conference call was immediately scheduled and the following information noted: The incident had actually taken place on 2/22/24 with no notification to the Agency. It was stated that the licensees authorized user removed the damaged sources using pliers and placed them in secured storage but did not follow their approved emergency procedures to cease work and rope off the area at 20 feet. The licensee contacted their consultant (R.M. Wester), and they were on-site the same day. R.M. Wester personnel surveyed the area and assumed there was no contamination because they were getting the expected radiation levels. At that time, the consultant recommended that the licensee contact the manufacturer (Berthold) to come out and further evaluate the sources and devices. The manufacturer was on-site on 3/7/24 and discovered that two source rods were damaged. The manufacturers rep advised a call to the State was needed. He noted one source rod had been damaged to the point the internal Co-60/nickel wire was exposed. On the afternoon of 3/8/24, Alton Steels licensed consultant surveyed the mold lid and found what they assumed to be the remaining portion of the source (exposure rate of 50 mR/hour). On 3/8/24, Alton Steel personnel used a torch to cut that portion of the source from the lid of the mold. This piece was also placed in secured storage. The lid was then surveyed by the consultant which he stated evidenced no further radioactive material. The two damaged sources, as well as the source rod fragment, are pending disposal. The Agency has requested that the lid and mold be held for surveys when Agency staff are on-site. Agency staff plan to be on-site 3/13/24 to further investigate. Leak tests from the consultant did not evidence removeable contamination in excess of 0.005 uCi. At this time, there is no indication of risk to workers or the public as all sources are in secured storage. The investigation is ongoing and updates will be provided as available. On Monday, 3/11/24, Agency staff conducted interviews with the Berthold service representative which conducted the service call. Information from that call indicated the licensee had cut through a source with a torch. At this point, Agency staff responded that morning to take surveys and interview Alton Steel staff. Survey readings were taken with a microR meter, which lacked the necessary sensitivity and were inconclusive due to [naturally occurring radioactive material] NORM and refractory material. Investigation findings indicate the licensee failed to follow emergency procedures, failed to follow operating procedures, failed to adhere to license conditions, received inadequate and incorrect training, improperly handled and manipulated sealed sources, failed to perform surveys, and failed to make timely notification to the Agency. The licensees consultant also failed to notify the Agency, lacked sufficient knowledge of the sealed source and performed inadequate surveys. Additionally, it was discovered the licensee had used a 4 inch die grinder on one source, cut through another with an oxygen lance, had a practice of handling unshielded source assemblies and an inadequate radiation safety program. Agency staff arrived at the licensees site again on 3/13/24 to perform additional surveys. Upon arrival, the licensee stated they had found yet another piece of the Co-60 rod source under the spray booth that washes down the cast billets. This was reportedly the area below where the source was first cut with a torch. The Agency confirmed the licensee was aware of the source when using the torch and did not perform surveys or alter operations. The second source which was found to be damaged had also been inadvertently withdrawn from its shielded housing when the molten steel overflowed atop the mold cap. However, the second source immediately fell into two pieces, apparently suffering damage within the housing. That source was reportedly burnt/melt and would not fit into the shield. A licensee gauge user then used a 4 inch angle grinder to smooth out the source so it would fit back into the shield. Agency staff investigated all areas accessible (some areas were inaccessible due to molten steel). A portable germanium spectrometer was employed to discern if elevated count rates were from NORM or Co-60 contamination. Preliminary findings indicate at least two areas adjacent to the vise (where grinding had occurred) had Co-60 contamination. Samples were collected for lab analysis and additional area surveys performed. The [Illinois Emergency Management Agency - Office of Homeland Security] IEMA-OHS lab reported on the afternoon of 3/13/24 that samples did evidence Co-60 contamination. The Agency covered the contaminated area and required it to be posted. Additional surveys will be taken once accessible, to include the wash-down water sedimentation areas. A full survey and remediation plan will be required by the end of the month. Decontamination efforts will be undertaken by a qualified contractor and the Agency will perform verification surveys to support release. Updates will be provided as they become available. Notified R3DO (Hills), IR MOC (Crouch), NMSS (Williams), NMSS Events (email) Notified DHS SWO, FEMA Ops Center, USDA Ops Center, HHS Ops Center, DOE Ops Center, CISA Central Watch Officer, EPA EOC, FDA EOC (email), Nuclear SSA (email), FEMA NWC (email), CWMD Watch Desk (email)
On 3/15/2024, the Agency dispatched seven inspectors to perform comprehensive surveys of the facility, characterize exposures, and determine if additional fragments of the source remained unaccounted for. Inspection findings indicate that there is Co-60 contamination within a single room (mold repair room) at Alton Steel. The licensee has secured the room and implemented contamination control procedures. Updated procedures and training were implemented on Friday, March 15, 2024. Extensive Agency surveys of the facility and personnel performed on 3/15/2024 indicate that the contamination is not being carried offsite; nor was there any indication of public exposures. There is no contamination of water. Contamination of the product (steel) has not been identified; nor is it likely to be a concern resulting from this incident. Due to improper handling of sources, it is likely a gauge user received an extremity dose in excess of regulatory limits. Time-motion study will be performed to refine dose estimates and substantiate. ONS-RAM is investigating additional, chronic internal exposures to Co-60 which have likely occurred over many years. ONS-RAM will return to the site on 3/20/2024 to evaluate the efficacy of contamination control measures, determine the timeline for remediation activities and perform additional sampling/surveys to better quantify exposures and determine the appropriateness of bioassays. This report will be updated as additional information becomes available. Notified R3DO (Hills), NMSS (Williams), NMSS Events (email), NMSS Regional Coordinator (Rivera-Capella) (email)
The following is a summary of information received from the Illinois Emergency Management Agency (the Agency) via email: The Agency conducted additional site visits on 3/15, 3/21 and 3/29. The following updated assessment is available: Contamination and Radioactive Material Accountability: Inspection findings indicate the licensee has used grinders/wire wheels on licensed sources to remove solidified steel both in response to this incident and others. In at least two instances, the grinding has penetrated the stainless-steel capsule and impacted the internal Co-60 wire. This led to contamination in the area referred to as the "mold repair room". Activities giving rise to this contamination and occupational exposures have been identified and ceased. Both can be traced back to inadequate training and a failure to follow operating/emergency procedures. Additional surveys, wipes and air sampling activities performed by the Agency indicate the Co-60 contamination is isolated to the "mold repair room" and is not being re-suspended, distributed throughout the facility or rendered available for inhalation/ingestion. Personnel and vehicle surveys have indicated no contamination. Surveys of locker rooms, bathrooms, elevators, adjacent areas, water circulation and sedimentation systems have all indicated no contamination. The licensee is working with a licensed service provider to perform characterization surveys and mobilize for proper remediation of the area. In the interim, the licensee has implemented appropriate access controls, personal protective equipment (PPE), surveys and additional contamination control measures. Working with the manufacturer, the Agency estimates a combined 328 microCi of Co-60 remains unaccounted for from the two damaged sources. At this point, licensee and Agency surveys limit the likelihood the fragments remain on site on the casting deck, spray down chamber or the resulting collection systems. On 3/29/24, the pathways in which the source fragments could be re-introduced into cast billets was investigated. However, the Agency surveys performed on 3/29/24 of billets representative from heats conducted after the incident date as well as the resulting roll-formed products; all yielded radiation readings consistent with background. Occupational Exposures and Contamination: Agency inspectors confirmed estimates of exposure which led to an employee exceeding the annual occupational limit for an extremity (114 rem to the hands). The employee has ceased work with radioactive materials for the year. Inadequate training and failure to follow operating procedures are causative for improper handling and damaging sources. In addition, the improper handling of sources is due, in part, to an unauthorized modification of the sealed source, dated shielding assemblies and repeated physical damage/fouling of the threads atop the sealed source. Based on all information available to the Agency, this is the most likely disposition of the 328 microCi of Co-60. While the sheer volume of the pile, size of the casting remnants and shielding afforded to the 328 microCi of Co-60 is unlikely to yield productive surveys; Agency staff will evaluate on 4/8/24. The Agency will continue to assess contamination control measures and evaluate the licensees contracted characterization surveys and remediation activities. The Agency will review proposed remediation goals, evaluate the resulting remediation plan, and perform verification surveys once the final status survey is received. Appropriate enforcement action and updating of the license is pending. Notified R3DO (Edwards), NMSS (Williams), NMSS Events (email), NMSS Regional Coordinator (Rivera-Capella) (email)
The following is a summary of information received from the Illinois Emergency Management Agency (the Agency) via email: The Agency conducted additional site visits on 4/5/24 and 4/8/24. Agency inspectors confirmed estimates of exposure which led to an employee exceeding the annual occupational limit for an extremity of 95 rem to the hands, not 114 rem as previously reported. The Agency will continue to assess contamination control measures and evaluate the licensees contracted characterization surveys and remediation activities. The Agency will review proposed remediation goals, evaluate the resulting remediation plan, and perform verification surveys once the final status survey is received. Pending no further developments and proper remediation of the impacted room; this incident report is considered closed. Notified R3DO (Betancourt-Roldan), NMSS (Williams), NMSS Events (email), NMSS Regional Coordinator (Rivera-Capella) (email). THIS MATERIAL EVENT CONTAINS A Less than Cat 3 LEVEL OF RADIOACTIVE MATERIAL Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf |
| Where | |
|---|---|
| Alton Steel Alton, Illinois (NRC Region 3) | |
| License number: | IL-01738-01 |
| Organization: | Illinois Emergency Mgmt. Agency |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+31.03 h1.293 days <br />0.185 weeks <br />0.0425 months <br />) | |
| Opened: | Whitney Cox 13:02 Mar 8, 2024 |
| NRC Officer: | Thomas Herrity |
| Last Updated: | Apr 16, 2024 |
| 57016 - NRC Website | |
Alton Steel with Agreement State | |
WEEKMONTHYEARENS 570162024-03-07T06:00:0007 March 2024 06:00:00
[Table view]Agreement State Damaged Gauges 2024-03-07T06:00:00 | |