ML20212H385
| ML20212H385 | |
| Person / Time | |
|---|---|
| Issue date: | 04/16/1998 |
| From: | Cool D NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| To: | Greeves J, Haughney C, Ten Eyck E NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| NUDOCS 9804230084 | |
| Download: ML20212H385 (4) | |
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UNITED STATES g
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NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555 4001
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April 16, 1998 l
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MEMORANDUM TO: Charles Haughney, Acting Director j
Spent Fuel Project Office, NMSS John T. Greeves, Director Division of Waste Management, NMSS Elizabeth Q. Ten Eyck, Director Division of Fuel Cycle Safety and Safeguards, NMSS Frederick C. Combs, Acting Chief Operations Branch, NMSS/IMNS Larry W. Camper, Chief Materials Safety Branch, NMSS/IMNS FROM:
Donald A. Cool, Director a
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Division of industrial and Medical Nuclear Safety, NMSS
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SUBJECT:
SUBMITTAL OF NEW GENERIC ISSUES FOR TRACKING IN THE GENERIC ISSUES MANAGEMENT AND CONTROL i
SYSTEM (GIMCS)
On March 23,1998, we provided a list of potential new generic issues to Carl Paperiello including commitments to submit some of the issues to RES for tracking in GIMCS. The detailed information RES will need to enter these issues into the tracking system is outlined in. An example is provided also. The list we provided to Carl Paperiello is provided in Attachment 2. The prioritization criteria from Policy and Procedures Letter 1-57 are provided in Attachment 3.
We request that each division / branch provide the detailed information in Attachment 1 by April 30,1998, for each new issue as follows:
OB/IMNS:
Year 2000 issue (IM-1) 7 ICRP-60 Internal Dose Mode M
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1 MSB/IMNS:
Amersham Cable issues (IM-2) f~ M' b o l
Troxler Weld Failure issues (IM-5)
Apgee-Berthold Gauge Failures (IM-6)
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y CONTACT: Kevin M. Ramsey, NMSS/IMNS (301) 415-7887 C W'd e d._
9804230084 9PW#.t PDR ORG
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Charles Haughney et al.
-2 Original signed by D. A. Cool DWM:
Radionuclide Transport and Behavior (WM-4)
Groundwater Monitoring and Restoration at Uranium In-Situ Extraction Facilities (WM-5)
Adequacy of Part 150 Criticality Requirements (WM-6) 7 Adequacy of 0.05 Weight Percent Limit in Part 40 (WM-7) l FCCS:
Criticality Benchmarks for <5% Enrichment (FC-1)
SFPO:
Dry Cask Welding Cracks (SF-2)
Package Testing (SF-3)
Attachments:
- 1. Generic issue Information
- 2. List of issues 1
- 3. Prioritization Criteria l
cc: C. Paperiello 1
DISTRIBUTION:
NRC Central File IMNS r/f NMSS r/f PDR: YES X NO DOCUMENT NAME:
GYoENERIC.KMR
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4/WI95 To receive a copy of this document, indicate in the box:
"C"= Copy w/o att/enci. "E" = Co 3y w/att/ encl."N" = No copy Y-/JJ M D OFC OB E
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[ h lb-NAME DATE 4//Y/98 4/ if /98 4//h'/98 OFFICIAL RECORD COPY IMNS/SEC
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i GENERIC ISSUE MANAGEMENT CONTROL INFORMATION ltem Number Illlit Pnonty (Refer to criteria in Attachment 3)
Lead Office NMSS/
Other Office Task Manaaer TAC Number Work Authorization Contract Title (if applicable)
Contractor / FIN No.
(if applicable)
Work Scooe (Describe issue and plan for resolution. If there is a contract, summarize the statement of work.)
Affected Documents (List NUREGs or other documents that may need to be revised.)
Milestones Oriainal Date Current Date Actual Date Status (Describe current status of resolution effort.)
Problem / Resolution (Describe special problems that have been, or will be encountered by the resolution effort and plans for resolving them.)
EXAMPLE OF COMPLETED INFORMATION Item Number NMSS-0006 Iille Criticality Concems With Unusual Moderators in Low-Level Waste Prionty Medium l
Lead Office NMSS/DWM Other Office RES/DRA Task Manaaer T. Harris, NMSS l
C. Nilsen, RES l
TAC Number Work Authorization l
Contract Title Criticality Concerns With Unusual Moderators Contractor / FIN No.
ORNL, FIN W6979 Work Scooe The contractor will develop the necessary information for documenting the technical and safety bases for criticality safety regulations in relation to unanticipated fissile materials and unusual moderators enterirg in to all areas of the fuel cycle and waste programs. Both technical and practical i
issues should be investigated and discussed. For LLW shallow land disposal, a generic methodology for evaluating the risk of a post-disposal criticality should be developed in order to reduce any residual uncertainty l
concerning criticality safety. If modifications to the existing regulations are recommended as a result of the study, the technical basis should be discussed. These technical bases should be quantitative and include identification of assumptions and appropriate supporting calculations. As an additional subsequent effort, the contractor should also be prepared to provide technical assistance to aid the NRC technical monitor on questions arising from public comments on any proposed regulatory change and, as needed, provide information that may be required to finalize rulemaking.
Affected Documents -
Milestones Oriainal Date Current Date Actual Date Issue user-need request for study 6/97 6/97 Issue request for bids 11/97 11/97 Receive bids 3/98 Award contract Receive draft report Accept final report Implement necessary regulatory changes Close out activity Statu1i RFP issued to ORNL 11/24/97. Proposal expected 3/98.
l Problem / Resolution None.
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March 23, 1998 MEMORANDUM TO: Carl J. Paperiello, Director j
Office of Nuclear Material Safety and Safeguards FROM:
Donald A. Cool, Director 3,_.
Division of industrial and Medical Nuclear Safety, NMSS
SUBJECT:
SUBMITTAL OF ADDITIONAL ISSUES FOR TRACKING IN THE GENERIC ISSUE MANAGEMENT AND CONTROL SYSTEM (GIMCS)
After your recent meeting with the Chairman, you provided us with a list of potential additions to the agency-wide generic issues tracking system maintained by RES. We have coordinated your suggestions with the other divisions, and obtained input on additional issues we believe should be submitted to GIMCS for tracking. Our summary of the issues is attached for your review.
Attachment:
Potential New issues i
I cc: E. Ten Eyck J. Greeves C. Haughney CONTACT:
Kevin M. Ramsey, NMSS/IMNS (301)415-7887
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DISTRIBUTION:
NRC Central File RJohnson IMNS r/f SRosenberg NMSS r/f YChen PDR: YES X NO LCamper DOCUMENT NAME: G:newissuz.kmr To receive a copy of this document, indicate in the box:
"C"= Copy w/o attlencl. "E" = Co py w/att/enci "N" = No copy 3 /M / $8' C4.-
OFC IMOB k if(d31 )
IMNS KRamIe"y"If Fhchs; YDC6oT NAME DATE 3/.20 /98 3/
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/98 OFFICIAL RECORD COPY I
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1 Potential New NMSS Generic issues:
lMNS IM-1 Year 2000 issue - The Year 2000 computer problem has the potential to pose a threat to
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public health, site safety & safeguards, and worker safety. Many computer systems may potentially fail to recognize the change to a new century. These systems may misread the year 2000 and thus may cause the systems to fail or generate faulty data.
Resolution: NMSS has taken a number of actions to encure that the Year 2000 computer problem will be either eliminated or minimized for its materials licensees.
l These actions include issuing information notices on the Year 2000 issue, coordinating l
with FDA regarding medical devices, establishing a Year 2000 team to address Year 2000 impacts on materials and fuel cycle licensees, conducting interviews with the management of materials and fuel cycle licensees to identify Year 2000 issues, l
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publishing articles in industry publications, and following up on all activities through personal contact by materials and fuel cycle inspectors. NMSS will issue a Ger~ic Lctter to fuel cycle liceneces addressing the Year 2000 problem. NMSS will continue to produce Newsletter articles or information Notices to emphasize the Year 2000 problem.
Although viewed primarily es a compliance issue, it involves significant staff effort. We will submit this to RES for tracking as a generic issue.
IM-2 Amersham Cable issues - During November and December 1997, NRC received 3 l
reports of radiography source disconnects involving drive cable failures (see EN 33351, PN-1-97-75, and PN-3-97-93). Each of these incidents involved Amersham equipment.
Information Notice 97-91 was issued on 12/31/97 to alert all radiography licensees to the problem. Amersham is analyzing the cable functions.
l Resolution: Special team inspections have been conducted at Amersham facilities in Massachusetts and Louisiana Additional followup actions will be considered after the investigation report is issued.
Submittir.g this issue to RES for tracking as a generic issue will be considered at the l
next Operational Events Briefing. The issues resulting from the staff's evaluation could prove to be generic safety issues or could only result in modified surveillance.
IM-3 Low-Level Radiation Risks - it is unclear what issue this refers to, but we believe it refers to the debate over whether the Linear-No Threshold (LNT) model should continue to be used as the basis for the dose limits in NRC regulations. We are not aware that j
the staff has been tasked with any specific action to address this issue. We believe that j
l the ongoing debate in professional societies and other forums may lead to a petition to use a different model as the basis for NRC dose limits.
We do not intend to submit this for tracking as a generic issue.
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IM-4 ICRP-60 Intemal Dose Models - Internal dose calculations require the use of mathematical models to estimate the organ doses resulting from intakes of radioactive materials. Assessment of intakes, on the other hand, can often be made without the use of models, especially when the available data is in the form of measured air concentrations or whole body counting data. The major revision of Part 20 changed internal exposure control from regulation of intake to regulation of committed dose equivalents. This change makes internal dose models critical to demonstrating compliance with Part 20. It is generally believed that the newer models provide more accurate estimates of the doses resulting from exposure to radioactive materials. There are no explicit references to models in Part 20, however the ALl's and DAC's in Appendix B of Part 20 imply that the models used to calculate them (ICRP 26 and 30) are the models that must be used to demonstrate compliance.
Resolution: On 11/4/97, GAP tasked IMOB with preparing information and recommendations concerning the use of newer dose models to demonstrate compliance with NRC regulations. On 11/14/97, IMOB recommended that licensees should be permitted to use the rmst recent, generally-accepted models in calculating doses to show compliance. Licensees should be pernud to establish new All's and DAC's for use in their facilities basea on these models. IMOB proposed changes to Part 20 and regulatory guides. On 12/17/97, GAP requested the input of the IMNS Senior Level Health Physicist. IMNS plans to prepare a generic letter to all NRC licensees discussing the staff position on dose models acceptable to NRC for dernonstrating compliance with the regulations. This letter will be coordinated with NRR and submitted to the Commission for review before it is issued.
We will submit this to RES for tracking as a generic issue.
IM-5 Troxler Weld Failure issues - On 6/25/97, the source from a Troxler moisture density gauge broke off the source rod and was left at a temporary job site (see PN-1-97-42).
On 7/17/97, NMSS and North Carolina staff met with Troxler to discuss the ongoing problem with cracked and broken source rods. Information Notice 96-52 previously recommended that users inspect source rods for cracks. There have been 6 known disconnects and 57 additional devices with cracked welds.
Resolution: In August 1997, North Carolina planned to issue a " consent decree" to Troxler confirming that they will issue a customer bulletin, conduct accelerated device inspections, revise procedures, and perform additional tests. At the September 1997 Operational Events Briefing, this issue was approved for submittal to RES as a medium-priority generic safety issue. The North Carolina consent decree h.3 received extensive review and comment by State legal staff. As of January 1998, it had not been issued yet.
Referral of this issue to RES has been delayed by higher priority work. The referral memo is currently in concurrence.
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IM-6 Acaee-Berthold Gauge Failures - On 9/14/97, a cobalt source fell out of a density gauge at a steel plant. A bolted plate fell off the device. It is unclear from the device registry whether the plate should be welded or bolted. Several Apgee customers have reported loose bolts.
Resolution: A CAL was issued confirming that Apgee would stop distributing bolted devices. Response to CAL claims that users are loosening bolts, but we disagree. The evaluation of the root cause assessment is ongoing. We may recommend that the vendor replace the bolted design with a welded design.
This did not appear to be a significant issue warranting referral to RES, however on 2/5/98, the source housing of a gauge at another facility shifted several inches (see EN 33659). Although the source remained shielded,it appears that the gauge experienced complete weld failure. This new information is being reviewed. We do not intend to submit this to RES for tracking as a generic issue.
DWM WM-1 Kev Technical Issues (KTis) - The high-level repository program 10 KTis should not be submitted to RES for tracking as generic issues because they are unique to the geologic repository at the Yucca Mountain site. They have no applicability to other waste programs or sites. However, the proposed generic issue listed below for radionuclide transport has some applicability to KTis that involve flow, radionuclide transport, and the nearfield environment. Submittal of the radionuclide transport issue to the generic issues tracking system is preferred.
l WM-2 Underoround Critical 4y - This issue involves the potential for special nuclear material (SNM) to mobilize and reconcentrate to form a critical mass after it has been buried at a low-level waste site. Studies of the burial sites at Envirocare, UT and Barnwell, SC concluded that criticality is unlikely when the moderators silicon dioxide and water are present. However, a study of the moderators carbon and beryllium in waste drums concluded that the presence of these moderators in excess of 5 times the mass of U-235 serves to reduce the areal density of the fissile material required for criticality.
Reso'ution: On 7/27/97, a user-need memo was issued to RES requesting a study of the role of unusual moderators such as carbon and beryllium in LLW disposal systems to determine their effect on the potential to develop a critical mass. On 8/5/97, this issue was submitted to RES for tracking as a medium priority, generic safety issue.
On 9/19/97, a supplemental user-need memo was issued to expand the scope to include development of a methodology to quantitatively evaluate the risk of post-disposal criticality.
WM-3 Consistent Modeling Parameters - This issue involves defining an appropriate set of parameters which are consistent with empirical information for use in modeling dose for decommissioning.
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Resolution: DWM plans to identify a research user need and request research to be conducted.
We will submit this for tracking as a generic issue when the user need memo is issued.
l WM-4 Radionuclide Transoort and Behavior in the Environment - This involves a variety of t
issues related to radionuclide transport including -- (1) developing a methodology for selecting and testing groundwater flow and transport models, (2) demonstrating surface complexation modeling in performance assessment, (3) field studies and analysis of soit property data, and (4) developing and testing infiltration evaluation methodology. This issue has broad applicability to decommissioning of contaminated sites, radioactive waste disposal, and uranium recovery activities.
j Resolution: Continue ongoing generic research project.
We will submit this for tracking as a generic issue.
l WM-5 Erfdictina Post-Restoration Groundwater Quality Monitorina and Restoration Pumoina Volumes at Uranium in Situ Extraction Facilities - This issue involves developing an approach to determine an appropriate period of post-restoration groundwater quality l
monitoring at uranium in situ leach extraction facilities. It also involves developing a methodology to calculate the groundwater pumping volumes needed for restoration of the mine zone in aquifers associated with uranium in situ extraction facilities. This issue has applicability to assessments of all uranium in situ extraction restorations.
Resolution: Continue research defined in user need memos dated 4/1/97 and 4/8/97.
We will submit this for tracking as a generic issue.
WM-6 Adeauacy of Part 150 Criticality - As a related matter to WM-2, the Envirocare review and the transfer special nuclear material (SNM) licenses to Agreement States for the Richland and Barnwell low-level waste disposal facilities surfaced an issue regarding the j
criticality safety of low-level waste as it is placed for disposal. Although individual shipments of waste may remain below critical mass limits in Part 150, placement of multiple shipment in close proximity could possibly result in a criticality accident. NRC staff's initial assessment concluded that the likelihood of such a criticality was very low under present operating procedures at the waste disposal facilities. However, changes l
in these procedures could substantially reduce, if not eliminate, this safety margin. The l
State of Washington retains a satisfactory license condition on the areal density of SNM for the Richland low-level waste disposal facility. In contrast, the State of South Carolina did not impose an areal density limit on SNM emplacement in the disposal trenches; this condition was deleted upon transfer of regulatory authority from NRC to the State. It is not clear whether the Agreement States recognize the potential need for restrictions on the emplacement of SNM waste. They may assume that a criticality is 4
precluded by adherence to the critical mass limits in Part 150. This could affec+ existing low-level waste disposal facilities, as well as planned disposal facilities.
Resolution: DWM has proposed to develop guidance on acceptable methods to tJess and prevent an inadvertent criticality during the emplacement of low-level waste for disposal. DWM also plans to coordinate this guidance with the Agreement States.
These plans are described in SECY-98-010, which is presently being reviewed by the Commission. Over the longer term, the Commission may wish to require Agreement States to evaluate emplacement criticality safety under 10 CFR 61.16(b)(2).
We will submit this issue to RES for tracking as a generic issue.
WM-7 Adeauacy of 0.05 weioht oercent limit in Part 40 - Recent assessments of potential recycle / reuse scenarios have raised questions about the unconditional release of chemical mixtures, compounds, solutions, or alloys that contain less than 0.05 weight percent source material (exempted under 40.13). Some assessments indicate '"$t niambers of the public could receive doses exceeding 100 millirem per year.
Resolution: RES is coordinating a contractor report entitled " Systematic Radiological Assessment of Exemptions for Source and Byproduct Materials." The report addresses a number of exemptions including 40.13. It is currently undergoing peer review. In addition, it is our understanding that two rulemakings related to this issue are currently on hold. One rulemaking would revise the definition of source material, and the other rulemaking would require NRC approval before exempt quantities could be transferred to unlicensed persons.
We will submit this item to RES for tracking as a generic issue.
EC_SS FC-1 Criticality Benchmarks >5% Enrichment - The availability of experimental data to support nuclear criticality safety (NCS) evaluations does not provide sufficient information to validate NCS calculations for all required configurations at U-235 enrichments in the range of 5-20%. This issue potentially affects uranium enrichment, commercial fuel fabrication, transportation, use in reactors, and both fresh fuel an spent fuel storage.
Currently, the commercial fuel facilities are not authorized to produce fuelin excess of 5% enriched uranium. However, more licensees are showing interest in increasing enrichment levels for their processes. One fuel fabricator has indicated intent to submit a license amendment request for processing >5% enriched uranium in July or August 1998.
Resolution: In the short term for some configurations, NCS calculational methods may be extended beyond the range of experimental conditions. However, various calculational methods should be used to provide a better estimate of the bias, uncertainties, and sensitivities in the extended area. NRC reviewers should ensure that 5
licensees who wish to operate in this range have made correlations in the expected compositions and affected variables, and have applied sufficient conservatisms in the l
calculations and margins to ensure safe operations.
In the long term, NMSS has requested the cognizant ANSI committee to assess the need for a new industry standard or revisions to existing standards to ensure safety in processing and using uranium enriched to greater than 5%. In addition, NRC needs to obtain additional criticality benchmark experimental data for representative systems with l
uranium enrichments between 5-20%. Recent research performed for NRC by Oak Ridge National Laboratory shows promise in allowing the extrapolation of existing l
criticality codes to cover the lower end of this range for certain systems. Los Alamos National Laboratory has done some experiments in this area and is still working on the study. The International Criticality Safety Benchmark Evaluation Project is also compiling experimental data from various countries which may be applicable. We plan to continue monitoring such activities for applicability to licensed activities.
We will submit this fortacking as a generic issue.
FC-2 Exoandina the definition of SNM to include other fissile material-The definition of special nuclear material (SNM) means plutonium, U-233, U-235, or any other material the Commission determines to be SNM. Questions have been raised about the need to expand the definition of SNM to include other fissile materiais (i.e., americium, californium, etc.). This will not be an issue for NRC unless we assume greater responsibility for independent oversight of DOE's nuclear complex. DOE facilities possess and process substantially greater quantities of these additional fissile materials than current NRC licensees.
Resolution: No action for NRC until long term responsibility for external regulation of DOE nuclear facilities is clarified. In the interim, NRC simulated regulation of the Oak Ridge Radioisotope Engineering Development Center in DOE External Regulation Pilot ll will provide insights into criticality safety, safeguards, and other aspects that are unique to these additional fissile materials. NRC will be able to use these insights in determining the need for, and issues associated with, potential rule changes that would be appropriate to address safety and safeguards concerns.
We do not intend to submit this for tracking as a generic issue.
SFPO SF-1 Burnuo Credit - DOE is seeking approval of a methodology for taking credit for fuel burnup in the criticality safety analyses of spent fuel containers (storage, transport, and disposal). Current criticality analyses assume spent fuel is fresh and unirradiated.
Under burnup credit, these analyses will include the reduction in reactivity that occurs l
when the fuelis burned in a reactor. A topical report on the methodology was submitted for NRC review on May 31,1995.
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Resolution: In response to NRC's request for additional information (RAl). a revised topical report was submitted on May 15,1997. A second RAI is has been drafted and is presently in the concurrence process. Burnup credit can save costs by allowing more spent fuel to be placed in a container which reduces the number of containers and shipments needed.
SFPO is handling and tracking this issue which contains a number of sub-issues. We do not believe this is a safety issue, and do not intend to submit it to RES for tracking as I
a generic issue. However, assistance from RES may be requested in the future for specific technical expertise to help evaluate some of the more complex sub-issues.
Otherwise, all future reviews will be in-house.
SF-2 Drv Cask Weidina Cracks - During nondestructive testing (PT/MT and helium leak test) of the VSC-24 dry fuel storage container closure welds, cracks have been discovered on four containers. Each of these weld cracks was repaired before being placed into service. The function of the closure welds is twofold - to maintain a confinement l
boundary to preclude leakage of radioactive material and to maintain an inert gas i
environment within the container to preclude long term Jadding and fuel degradation from oxidation. These welds are to remain intact for normal, off-normal, and accident (drop) conditions.
Resolution: In May 1997, NRC issued CALs to SNC and each VSC-24 user to determine the root causes of the weld problems and develop corrective actions to l
preclude recurrence. SNC has determined that the root causes for each occurrence were different and proposed several corrective actions to preclude recurrence of the identified weld cracking problems. Of concern is the potential for delayed cracking or introduction of subsurface defects (via a weld process malfunction) that would not be detectable via current nondestructive test requirements. In response to a staff RAI, l
SNC and users of the VSC-24 system have committed to assessing the feasibility of a volumetric examination technique (UT) for the structural-lid closure weld to provide added assurance that this weld does not contain any unacceptable subsurface flaws.
This method would be used to inspect structural-lid closure welds on future containers l
and for re-examination of previously loaded containers (19 totalloaded to date).
i The potential for the introduction of flaws during welding processes is applicable to the final closure welds on any dry cask storage or disposal system design. In the past, a double welded closure for the final seal welds has been accepted because of the l
perceived difficulties involved in performing a volumetric examination of these welds.
However, current UT technology may provide a means to perform a volumetric examination of these welds. Volumetric examination of the closure welds would ensure consistency with requirements to volumetrically inspect c4her confinement system welds and consistency with the ASME Code.
We will submit this issue to RES for tracking as a generic issue.
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SF-3 Packaae Testina -In 1997, an inspection of Amersham Corporation identified problems with the adequacy of Amersham's package testing program. Specifically, the puncture test was performed using a bar that was not meunted as specified in 10 CFR 7173(c)(3). An inspection of Source Production and Equipment Company (SPEC) found the same problem.
Resolution: On June 10,1997, a confirmatory action letter (CAL) was issued to confirm that Amersham would retest their Type B packages. On June 24,1997, a CAL was issued to confirm that SPEC would conduct retesting also. On September 23,1997, f
Bulletin 97-02 was issued to all holders of NRC Certificates of Compliance for transportation packages. The responses to the bulletin identified packages that were not pimcture tested in accordance with 10 CFR 71.73(c)(3). In addition, there were a few packages for which the Cettifcate holder was unable to determine whether the i
puncture test was performed correctly. The followup of the bulletin responses is ongoing.
We will submit this issue to RES for tracking as a generic issue.
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CRITERIA FOR PRIORITIZATION GENERIC ISSUES (from NMSS Policy and Procedures Letter 1-57)
Hiah Priority issues which could cause abnormal occurrence criteria to be exceeded.
l Issues where resulting events require immediate or 24-hour notification.
Issues which could cause safety limits to be exceeded for multiple individuals or a substantial l
release to the environment.
l Medium Priority t
Issues which could cause safety limits to be exceeded for an individual or a release to the environment.
Issues where resulting events require 30-day notifications.
Low Priority All other safety issues.
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