ML20203E117
ML20203E117 | |
Person / Time | |
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Site: | 07000036 |
Issue date: | 02/12/1998 |
From: | NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
To: | |
Shared Package | |
ML20203E103 | List: |
References | |
70-0036-98-201, 70-36-98-201, NUDOCS 9802260266 | |
Download: ML20203E117 (19) | |
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e U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS Docket No: 70-0036 License No: SNM 33 Report No: 70-0036/98-201 License Holder: ABB Combustion Engineering Location: Hematite, MO Dates: January 12 - 16,1998 Inspectors: Christopher Tripp, inspection Team Leader, NRC Headquarters Dennia Morey, inspector, NRC Headquarters Douglas Outlaw, NRC Contractor Approved By: Philip Ting, Chief, Operations Branch, Division of Fuel Cycle Safety and Safeguards, NMSS Enclosure 2 9902260266 990212
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2 ABB COMBUSTION ENGINEERING NRC INSPECTION REPORT 70 0036/98 201 EXECUTIVE
SUMMARY
IntroductiQD NRC conducted a routine, unannounced nuclear criticality safety inspection of the Hematite, Missouri plant of ABB Combustion Engineering on January 12 - 16,1998. The inspection was conducted by NRC Headquarters staff, using Inspection Procedure (IP) 88015. The inspection was focussed in the highest risk areas of oxide conversion and uranium recovery, and included the following program areas:
- NCS Function e Plant Activities e NCS Change Control e NCS Training e NCS Inspections, Audits, and Investigations e Criticality Alarm Monitoring Systems e NCS Emergency Response o Followup of Previous inspection Findings Results e No immediate safety hazards were identified during this inspection.
e Seven of nine open items from inspection Report 70-0036/96 202 have been closed.
e Three violations of regulatory requirements were identified: one cited, as noted in the enclosed Notice of Violation, and two non-cited. These included violations concerning dualindependent sampling in the uranium recovery area, the existence of unapproved postings, and the positioning of oxide powder storage cans into storage arrays without the required moisture sampling, o Two unresolved items were identified, involving adequacy of analysis for the UO, powder cooler in the oxide conversion area, and completeness and accuracy of information provided to NRC concerning the status of the Criticality Safety Program Update (CSPU).
- Lack of a standard procedure to conduct event investigations, closure of corrective actions, and tracking and trending of criticality safety issues were program weaknesses.
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l CQnGlus0.0 There has been considerable progres in instituting procedures to administrate the NCS program and in the thoroughness of new criticality analysis. Apart from the missing oxide l cooler analysis, evaluations for the oxide conversion area were found to be in accordance with !
the license and program requirements, thorough, and accurate. Areas of weakness continue to I be lack of a documented safety basis outside the oxide cenversion area, event investigation, and follow through on recommended corrective actions. There is also a high reliance on administrative controls, and these controls are net consistently complied with, as evidenced by the number of control violations involving stacking of pellet trays, misuse of pellet only carts, and moisture sampling of containers.
BEPORT DEIAJLS 1.0 NCS Function SCOPE The inspectors reviewed several new administrative procedures, which had been issued as part of the CSPU, to determine whether they were adequate to implement all required NCS program elements. The inspectors also reviewed several nuclear criticality safety evaluations (NCSEs) to ensure that they existed for all processes and fiscile material operations, that they were done in accordance with procedures, and that they adequately established the safety basis of the plant.
OBSERVATIONS AND FINDINGS 1.1 Program implementing Procedures The inspectors reviewed the NCS procedures RAAP 109, ' Criticality Safety Program,' dated December 30,1997, and RAAP-108,
- Nuclear Criticality Safety Evaluations," dated March 14, 1997. The inspectors found that these procedures were generally adequate in addressing the program requirements of License Chapter 4. However, Te inspeciors noted a disagreement between the license and the procedure RAAP-109. L %nse Sectio" 4.2.4(k) states: ' Process systems shall be designed to minimize the likelihood fu accurW 9 of fissile material within the system, in addition, process procedures shall have provis. 4 $ varifying that fissile material has not accumulated within the system...." Section 5.1. 65 o RAAP-109 states: "The possibility of accidental accumulation of fissile materials in inaccessible locations shall be minimized through equipment design or admlnistrative controls or included in the nuclear safety evaluation of the process.* The license requirement is to minimize the potential for material accumulation through both equipment design and periodic monitoring, whereas the procedure is less stringent. While the licensee acknowledged that the language in the procedure appeared to weaken the license requirement, they did not commit to change the procedure, and so this item is being tracked as inspector Followup Item (IFI) 70-0036/98 20101.
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4 RAAP 109, Section 6.3 required daily checks for NCS related problems to be conducted by Health Physicists, and allowed minor problems to be corrected on the spot by a Production Supervisor. This is a potential weakness in that it allows problems to be categorized as ' minor" and corrected without consultation of NCS. The licensee did not agree and indicated that they thought training was sufficient to permit their operations personnel to make this determination.
License Application Section 2.6 states that
- Primary responsibikty and authority to suspend unsafe ope *ations is placed with line supervision.' The inspectors thus reviewed procedure RAAP 106, *Stop Work Authonty " Rev. O, dated September 30,1997, to verify that it delegates authority to stop unsafe operations to managers, supervisors, and the nuclear criticality safety specialist. The procedure also invests all employees with the responsibility to notify their management of any safety hazards or procedural or regulately violations, and thus adequately implements the license requirement.
1.2 Nuclear Criticality Safety Evaluations in response to inspection findings in inspection 96 202 concerning the quality of NCSEs, the licensee had committed in the Criticality Safety Program Update (CSPU) to review and update the criticality analyses and evaluations according to an approved schedule. Completion of the analysis update for oxide conversion was to be completed by April of 1997, with the balance of the plant to follow (starting with recycle / recovery and proceeding to the pellet plant front end and then storage units). In the last Quarterly Update to the CSPU, the licensee indicated that the update of the Oxide Conversion Facility had been completed.
The inspectors requested that the licensee identify the plant areas of highest risk of accidental enticality. The licensee identified the unfavorable-geometry portions of the Oxide Conversion Facility as the areas of highest risk. The inspectors concentrated their review of NCSEs and the associated controls in the Sighest risk areas in Oxide Conversion and also in Uranium Recovery. The inspectors reviewed the analyses for the bulk powder storage hoppers, the oxide conversion reactors, and the UO, screw cooler. When the inspectors asked for the NCSEs for the bulk powder storage hoppers and the UO, cooler, the licensee indicated that the required analysis was incorporated into Chapter 15 of the License Application. No other documented criticality safety evaluation existed. The inspectors reviewed the identified information and determined that it did not meet the requirements of procedure RAAP-108,
' Nuclear Criticality Safety Evaluations
- or License Application Section 4.1.3. The analysis did not consider potential scenarios to criticality, demonstrate the maximum credible moderation intrusion, or provide dimensions or equipment drawings. The analysis did not display any evidence of independent review and was not documented in sufficient detail such that an independent reviewer could reconstruct the analysis and the safety basis.
The licensee indicated that the arialysis of the bulk storage hoppers did not meet the above-mentioned requirements because it was considered outside of the oxide conversion area proper. This was considered part of the pellet plant front end operation, and thus this analysis had not been updated, according to the CSPU schedule. When questioned, the licensee indicated that everything upstream of the hoppers was considered part of oxide conversion.
When the inspectors indicated that the oxide cooler analysis was inadequate, the licensee responded that they did not update the cooler analysis because the equipment was due to be
5 replaced with a dry cooler of a different design in the near future. The cooler had, however, continued to operate in the more than eight months since the analysis update was supposed to have been completed in Oxide Conversion. The licensee later represented that License Application Section 4.1.3 only requires criticality evaluations to be associated with facility changes, and that existing equipment did not have to be evaluated for criticality safety.
The UO, cooler consists of a screw feeder surrounded with a liquid water cooling jacket, which also flows down the shaft of the cooler. Thus, the oxide is confined to an annular region coaxial with the screw shaft. This is the only piece of equipment in the oxide conversion area where the potential exists for oxide powder to contact liquid water. Because most of the conversion process occurs in unfavorable geometry vessels, such as the reactors, blenders, and various hoppers, and because moderation control is the primary control, the UO, cooler is the highest-risk piece of equipment in the entire conversion process. Failure to analyze this key piece of equipment for criticality safety is Unresolved item (URI) 70 0036/98 20102.
In response to the inspectors' concerns, the licensee produced drawings of the cooler and performed Monte Carlo analyses (using Keno 5 a). These new analyses showed that the license condition of k,, < 0.05 was met under both normal and credible abnormal conditions.
The abnormal condition consisted of breaching the heat exchanger wall and introducing uranium into the surrounding water jacket.
The licensee indicated in the September 30,1997, Quarterly Update to the CSPU that the analysis update for Oxide Conversion had been completed. During a conference call on February 5,1998, licensee NCS personnel stated that an analysis of the UO, cooler was not required because it has previously been analyzed as a
- Safe Individual Unit" as defined in the license. The licensee agreed to provide a copy of the as built drawings, along with the original safety evaluation. Review of this information to determine whether complete and accurate information was provided to NRC conceming the status of the oxide conversion analyses is URI 70-0036/98 201-03. The inspectors did not identify a safety hazard associated with this item.
The licensee further indicated that the UO, screw cooler was classified as a Safe Individual Unit (SIU)in Table 4.5 of Ucense Application Chapter 4. This would indicate that it was considered safe under optimal moderation and full reflection conditions. However, the inspectors did not identify any documentation establishing the cooler as an SIU. Other equipment in the table are also considered SIUs, such as vacuum cleaners, mop buckets, and filter presses. Howa 'er, there is no documentation v.hich establishes the necessary configuration of equipment to consider it an SIU (such as the necessary volume or dimensions of a mop bucket or vacuum).
Review of allitems considered SIUs in the plant, to ensure that they have sufficient analysis to justify their status as SIUs, and necessary controls to maintain them as SIUs, is IFl 70 0036/98 201-04.
1.3 Reliability of Controls The inspectors then examined the controls in place on the bulk storage hoppers and the UO, cooler to ensure that this equipment was doubly contingent and was operated safely. The licensee produced new calculations to show that the cooler would be suberitical under credible
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6 upset conditions of having optimally moderated UO, present in the inner and outer jacket as ,
well as the annular region. Becaute the cooler is larger than a safe diameter cylinder, the l poisoning effect of the steel shells is required to maintain suberiticality. Moisture sensors in the !
outlet side of the cooler protect against moderator intrusion and prevent further flow of material in the event of an alarm. The inspectors determined on the basis of this new information that the cooler was safe under normal and credible abnormal conditions, provided that its dimensions and material construction are maintained.
The controls in place on the hopper are two measurements of moisture content in thu receiver vessel, which accepts material from the outlet side of the cooler. One controlis a dew point sensor which alarms and shuts off the vacuum transfer blower to the receiver vesselif the dew point exceeds 15'C. The other is a moisture sample which is drawn before transfer to the bulk storage hoppers. The inspectors examined these controls and determined that they were adequate to ensure moisture content s 1 wt%. (A moisture of 7.5 wt% is needed to make an isolated storage hopper critical.)
The inspectors then reviewed the analysis A 31X 001, "The Oxih Conversion Process,"
Rev. O, and the evaluation E 312 001, "The R2 Reactor and We 3 Hopper," Rev. O. The inspectors determined that the documented analysis and evaluation was sufficiently detailed to permit reconstruction of the model, and included sample computer input docks in an appendix.
The analysis contained an adequate description of normal and abnormal conditions and identified accident scenarios, barriers, and demonstrated double contingency. The inspectors determined that this updated analysis generally met the requirements of RAAP 108,
- Nuclear Criticality Evaluation," and License Chapter 4. However, RAAP-109, Section 5.1.10, states
' Optimum conditions of water moderation, reflection, and heterogeneity shall be used in all calculations where credible, if optimum conditions are not used, the controls shall be stated."
The analysis did not cortcin sufficient information to determine how much reflection was used in the normal case; the analysis did not consider full reflection in the abnormal case or establish specific reflection controls. The inspectors noted that the reactor was surrounded by a thick layer of insulation and was required to be drained of material before being opened for maintenance, so that there was no safety issue.
The inspectors then reviewed the controls in place to ensure safe operation of the reactors.
The primary control is moderation, which is limited by the process temperature. UF. is reacted with dry steam to produce UO,F, and then defluorinated to UO, in the fluidized bed reactors.
The process temperature is maintained at a level suffident to prevent condensation of liquid water in the reactors. The temperature is controlled with a set of four thermocouples in each of three vertical sections of the reactor. The inspectors determined that two thermocouples must register a high or low temperature signal or fail in coincidence to generate an alarm, which will shut off the steam flow. The inspectors determined that the alarm logic circuitry is independent and that the alarm circuits and thermocouples are tested on a basis adequate to ensure reliable operation of this control. The inspectors also determined that mass controlis reliably maintained by the use of high pressure alarms, a rupture disk, and pressure relief valves.
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CONCLUSIONS l The implementing procedures for the nuclear criticality safety program were generally adequate. The new analyses and evaluations that were done as part of the Oxide Conversion Analysis Update were found to be robust and thorough, and demonstrated safe operation of these parts of the plant. The active controls were adequate and were maintained and tested in a manner that ensured their continued reliability. However, documentation of the safety basis in the remainder of the plant outside of the Oxide Conversion Facihty, and for the UO, cooler in oxide conversion, requires further improvement in accordance with the licensee's CSPU.
2.0 Plant Activities SCOPE The inspectors toured the faci!ity to determine whether administrative controls were being effectively communicated to the operations personnel and were complied with. The inspectors reviewed the criticahty safety postings used to communicate controls to operators.
OBSERVATIONS AND FINDINGS License Application Section 4.1.5 requires that the licensee maintain a current record of the rev%w and approval of each criticality safety posting along with a record of their location and coment The licensee maintains a comprehensive listing of criticality safety postings tha are currently in use. The licensee has no procedure or other requirement for the review and approval cf criticality safety postings. Development, review, approval, and preparation of the postings in the plant were found to be the responsibility of one individual employee. Postn,y are reviewed, approved, and signed off by the Director of Regulatory Affairs. The inspectors determined that approval consists of sign-off on the cover page of a comprehensive listing of all current criticality safety postings. This comprehensive listing is updated quartedy. If a posting is to be changed before the complete listing is due to be updated, then the Director of Regulatory Affairs reviews, approves, and signs off on a paper copy of the new posting, which is then retained until the next issue of the comprehensive listing.
The inspectors toured the facihty and compared criticality postings with the information contained in the licensee listing. The licensee database contained approximately 200 different postings with many being posted in multiple locations in the plant. The inspectors reviewed approximately 40 postings in several areas of the plant, in the Recycle Recovery Room, the inspectors noted discrepancies between the posted signs and the listing. Posting 118, which was observed to be displayed on a hood, was not in the listing. The licensee indicated that the posting was reviewed, approved, properly posted, and listed in the database, but did not print out because it was improperly labeled in the database as
- historical." Posting 202, which was also observed to be displayed on a hood, had different requirements posted than were in the listing. The posting said
- Filter Press and One 22 Liter Container Under Hood," while the database requires the posting to read " Filter Press and One Safe Volume Container Under Hood." The licensee indicated that the posted sign had been recently changed and was correct, but that the new requirements had not been updated in the database. As a result, the requirements had not been reviewed and approved prior to being posted. The requirements
8 were similar and the inspectors determined there was no safety issue. This item is considered a violation because there is no record that the revised posting was ever reviewed and approved. Because the licensee took immediate action to correct the listing, and because the posting did not constitute a safety hazard, this is being identified as Non cited Violation (NCV) 70 0036/98 201-05. The licensee stated that these issues were self identified because the licensee had begun an extensive effort to review the database in December 1997, and was about halfway dorie, although the inspectors noted that these specific deficiencies had not been identified yet as a result of the review.
The inspectors observed a violation of nuclear criticality safety controls in a storage array of dry powder cans on a conveyer outside the Erbia Product room. Both Posting 110 and procedure NIS 20100,
- Nuclear Safety Parameters," require moisture sampling of UO, powder cans prior to being stored in arrays on conveyer belts. The cans must be affixed with a blue tag with diagonal red stripes prior to being placed in this type of storage array Elsewhere in the plant, oxide cans without moisture certification are stored in single layers with required spacing between the cans. On two stacked conveyer belts, the inspectors observed a linear array of cans placed in contact with each other; one of the cans did not have the required moisture certification. The inspectors later determined that the lot from which the can was filled had been moisture sampled, and that the can contained approximately 140 g of dry UO, powder.
Thus, this appears to have been a failure to moisture certify this individual can and to then place it in the array without the required tag. The licensee investigsted the incident and determined that the storage array was in a safe configuration, and replaced the moisture tag.
Because of the configuration v as highly subcritical as found, and because this was an isolated incident, this is being identified as NCV 70 0036/98 20106.
CONCLUSIONS The inspectors determined that there is a heavy reliance on administrative controls in the plant and that the nuclear criticality postings are a main method of communicating these controls to the operators, it is therefore important that the postings be reviewed and approved in a controlled manner. However, the lack of review and approval requirements led to two observed cases of discrepancies between the record listing of postings and those observed on the floor.
The deficiencies in postings is a potential weakness in the flowdown of administrative controls.
The observation of a can in a storage array without the required moisture certification does not appear to have actual safety significance in the instance found; however, the existence of an undiscovered violation of criticality procedures and postings compounds the observation of a generallack of adherence to administrative controls.
3.0 NCS Change Control SCOPE The inspectors reviewed the criticality safety aspects of the licensee's change control process to confirm that it met license requirements, and was adequate to control changes to the safety
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basis of the plant. The inspectors also reviewed a sample of recent plant modifications to confirm that the change control process had been effectively implemented.
OBSERVATIONS AND FINDINGS License Application Section 2.6 states that " Prior to the start of a new activity affecting nuclear materials, approved procedures are available. A review procedure has been established for changes in processes, equipment and/or facilities prior to implementation. Regulatory Compliance authorization must be obtained for each change involving nuclear safety or radiological safety.' Specific cnteria for approving new and modified processes follow. During Inspection 96 202, inspectors had found that the licensee had not established a change control procedure that effectively ensured all changes in processes, equipment, and/or facilities of potential criticality safety significance were reviewed to identify changes in maintenance, testing, and surveillance needed to maintain criticality controls. This failure to meet the above license requirements resulted in Violation (VIO) 70-0036/96 202-02.
The inspectors reviewed the licensee's modified change control procedure OCP-5002.4,
' Change Control Management,' Rev. 01, dated April 9,1997. The inspectors determined that this procedure was adequate to implement the above license requirements. The form
- Notification of Change Control Management Evaluation" was modified to require that Regulatory Affairs concur on all Type I, Type 11, and Type lli changes. The ' Change Control Management Applicability Matrix" was also modified to classify all process, equipment, and facility changes as Type I changes. These modifications to the procedure should ensure that all such changes receive a thorough review by Regulatory Affairs. These modifications were deemed adequate to correct previously identified problems with the change control process.
The inspectors also reviewed change control documentation for several recent modifications to confirm that the new process had been effectively implemented. All of the changes sampled had received Regulatory Affairs reviews in accordance with the established procedure.
The inspectors noted that only one of four change control packages sampled used the
- Notification of Change Control Management Evaluation
- form referenced in the version of the Change Control Mragement procedure that wcs current at the time o' the changes. The other three packages used forms that had been superseded. There were no substantiva differences between the forms used. However,it was evident that the engineers initiating the forms had used an out-of-date change control procedure, that the reviewers had also approved forms from the out-of-date procedure. Discussions with staff indicated that the engineers received electronic mail notifications of the procedural revision, but that the mantgement system did not ensure that only current administrative procedures and forms were used. This is a potential vulnerability of the configuration management system for administrative procedures, and should be corrected. Review of management approved corrective actions to this concern will be tracked as IFl 70-0036/98 201-07.
The inspectors reviewed one change to plant processes that allowed the relaxation of criticality safety controls to allow increased throughput (the dry recycle reactor boxes, or muffle fumaces). This change required a criticality safety analysis and evaluation, and resulted in changes to the criticality safety posting and mass limits in the computer inventory control.
Operating procedure O.S. 803.0, " Dry Recycle Processing,' was also revised and approved by
10 Regulatory Affairs. An effective date of July 22,1997, was established for the operating procedure, which was prior to completion of the criticality safety evaluation (July 31,1997) and the "Changa Control Closeout Checklist" (July 31,1997). Even though ihe procedure was in effect, the operational changes and new procedure were not implemented until completion of the closecut checklist. The inspectors reviewed the operating log and verified that the changeover to the new operating limits occurred after the closecut checklist was approved.
The change control system did not permit the procedure to be used prior to completion of the i
required closeout checklist, although establishing an effective date for revised operating procedures prior to completion of the criticality safety evaluations was an appa ent weakness in the cystem. It is not certain that any subsequent changes to the procedure made necessary by l the criticality evaluation would be captured by this system.
CONCLUSIONS The inspectors found that the licensee respo ises to Violation 70-0036/96-202-02 had effectively corrected specific vulnerabilities in the change control process. However, the inspectors also found that there were still weaknesses in the areas of ensuring that engineers l use the latest revision of management procedures and in issuing operating procedures prior to completion of the relevant nuclear criticality safety evaluation.
4.0 NCS Training SCOPE The inspectors reviewed the criticality safety training program and training materials to verify that the license conditions were met, and that training was adequate to ensure safe operation of the plant. Specific training records were not reviewed, as they were not readily available.
OBSERVATIONS AND FINDINGS License Application Section 2.5 requires, in part, that " Hematite staff conduct or supervise the indoctrination of new employees in the safety aspects of the facility. The indoctrination topics s! all include nuclear criticality safety....After test results demonstrate that a new employee has sufficient knowledge in the above topics, the new employee begins on-the job training under direct line supervision and/or experienced personnel.... Production supervisors receive formal training in radiation and criticality control." The inspectors reviewed the NCS training program against these requirements.
The inspectors discussed the criticality safety training program with the criticality safety staff.
Training requirements have been formalized in procedure RAAP-119, " Regulatory Affairs Training. Rev. O, dated January 30,1997. This procedure identified specific training requircr1ents for e.scorted and unescorted access to the Hematite facility, including criticality safety training requirements (specifically incorporating requirements for production supervisors; see Section 8.0).
Discussions with staff and review of training documentation indicated that all new staff having access to spec,al nuclear material (SNM) receive indoctrination training on the fission process
' J 11 and criticakty issues, as required by the license. In addition, fissile materi'al workers received on-the-job training under direct line supervision and/or experienced personnel until performance is determined adequate to permit work witM' close supervision. The nuclear criticality specialist assisted in both the basic critic, W :'ety tra ling nd the on-the-job training.
The inspectors reviewed the viewgraphs for the course " Nuclear Criticality Safety."
Discussions with the criticality safety staff indicated that this course had been substantially expanded and enhanced. All operators and production supervisors have received and been tested on this expanded criticahty safety course. The materias presented on the viewgraphs covered most of the fundamental requirements of ANSI /ANS-8.20-1991 for program content.
Specific sections of the presentation material that appeared weak involved information on the energy and yield of a criticality excursion (ANSI /ANS-8.20 Section 7.1.2) and reduction of dose as a function of time, distance, and shielding (Section 7.4.2). This knowledge is not important in preventing a critien! excursion, but may be important in limiting individual doses following an accident. The staff indicated that additionalinformation and detail was provided during the course. Overall, the training materials were found to be adequate.
The criticahty safety specialists responsible for training indicated that all operations and support staff were current in their criticahty safety training requirements. Because a key licensee staff member was in the hospital during this inspection, training records for plant staff were not available for review. Review of these records will be tracked as IFl 70-0036/98 201-08.
CONCLUSIONS The inspectors found that the ticensee's actions to ensure that criticality safety training is provided to the production supervisors, operations staff, and technical staff was adequate. The scope of the training was also adequate.
5.0 NCS Inspections, Audits, and investigations SCOPE The inspectors reviewed the internal audit, inspection, and investigation program to determine whether the program was adequate to find and correct nuclear criticality-related problems that arose in plant eperations, to ensure continued safe operation of the plant. The inspectors examined the t orrective actions in response to audit and inspection findings and criticality control violations to determine whether they were tracked to completion, prompt, and effective.
The inspectors also examined criticality violations to determine whether they were being screened correctly for Bulletin 91-01 event reporting.
OBSERVATIONS AN'D FINDINGS 5.1 Internal Audits and ir:spections License Application Section 2.8 requires daily safety checks by HP technicians, quarterly inspections by designated safety professionals, and annual safety audits by a designated safety team.
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12 The inspectors reviewed the most recent annual audit and determined that criticality safety issues had been reviewed, findings identified, and corrective actions recommended. This annual audit and the previot's audit have noted weaknesses in the documentation of corrective action. The licensee has not developed a procedure that contains requirements for the development, assignment, completion, or verification of corrective actions. Several procedures concerned with reporting of particular events also contained instructions for record-keeping, which the inspectors determined were inadequate for the purpose of assigning responsibilities j for corrective actions.
The inspectors reviewed the most *ecent quarterly criticality safety inspection, which was for the third quarter of 1997. The inspectors determined that the licansee inspection was thorough and identified numerous findings, but that corrective actions were not developed, assigned, or tracked to closure. For example, the inspectors noted t..dt an item listed in the inspection report appeared to be a violation of a criticality safety control. The item concerned a fissile material cart being too close to a mop pail. The item was not reported on a licensee Criticality Non-Compliance Review Request form, and therefore, no ree.ord of an investigation or a Bulletin 91-01 review is available. The licensee admitted that the item violated criticality safety limits snd should have been reported for the purpose of tracking and trending criticality safety violations. Use of the licensee criticality violation reporting system will be tracked as IFl 70 0036/98 201-09.
The inspectors determined that no records are retained to document daily safety inspections.
Items are reported by Health Physics technicians as they are observed during the course of their daily duties. The inspectors did not observe any documentary evidence that issues were being raised by these daily inspections. The licensee should evaluate whether these HP daily inspections are having the desired effect of monitoring plant operations for problems on a daily basis.
5.2 Internal Investigations License Application Section 2.9 requires formalinvestigation and documentation of events that are reportable under regulations or license conditions. Non-reportable occurrences or events are required to be investigated and documented as appropriate, and the resulting records are required to be available for inspection. The licensee does not have a specific procedure that describes what events will be investigated and how they will be investigated. The licensee identified instructions for documentation of reportable events in the specific reporting procedure, but the inspectors determined that these instructions did not adequately cover the area of investigations.
The chain of internal reporting begins with reporting of unusual occurrences or violations of requirements by plant employees. Licensee procedure NIS 201.00," Nuclear Safety Parameters? requires all employees to report any NCS violations to the NCS Specialist.
Events that involve criticality safety issues are investigated by the criticality specialist. There are no formal requirements for the conduct of these investigations, and the criticality specialist is able to investigate to whatever extend thougnt necessary. Records of investigations did not
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a sequence of events, or a discussion of root causes. Closed reports did not incNde documentation or verification of completion of corrective actions.
The licensee has recently revised procedure NIS 205.00,
- Nuclear Criticality Safety Event Reporting," to include direction for the documentation of events involving criticality safety issues. The licensee claimed that this newly revised procedure contained requirements for the conduct of investigations. The inspectors however determined that this procedure focussed on events considered reportablo under Bulletin 91-01 and did not contain clear instructions for the investigation and documentation of events.
5.3 Corrective Actions The licensee quarterly inspection report for the third quarter of 1997 included item 1.E.2, " Cart labeled pellet storage only being used for powder " During a walkdown in the facility, the inspectors observed a cart labeled " Pellet Storage Only" being used to store a bucket of vacuum cleaner waste and a bucket of powder. The licensee did not assign clear corrective actions in the quarterly inspection report, although it appears that the finding was assigned to a responsible party. License Application Section 2.8 assigns responsibility for corrective actions from quarterly inspections to the Director of Uranium Operations. The inspection report from the third quarter was dated October 16,1997, so that the licensee had sufficient time to correct the problem. This finding is potentially safety related in that it concerns a lack of operator adherence to posted instructions, which appears to be due in part to there being outdated instructions posted in several locations in the plant.
5.4 Bulletin 91-01 Reporting The licensee requires that events involving the loss of criticality controls be reported to NRC in accordance with NRC Bulletin 91-01 requirements. The licensee procedure requiring event reporting is OS 205, " Reporting Loss of Criticality Safety Controls," Appendix 1, and contains all material requirements of the Bulletin.
Employees report violations of criticality controls on a licensee form cclied a Criticality Non-Compliance Review Request. This form is directed to a supervisor who is then required to direct the form to the NCS Specialist (NCSS). The NCSS then determines whether the occurrence must be reported to the NR?,. The inspectors reviewed sixteen reported violations of criticality requirements to determine whether the liccnsee had corrcotly evaluated the e
occurrences for reportability. Fourteen of the reports involved the violation of aoministrative limits, five involved the violation of administrative controls on the content of hoods, and three involved the violation of administrative controls on the height of slabs of material. Three selected occurrences were walked down in the plant. Two of the selected occurrences involved violation of slab height and one involved failure to docume"* moisture analysis on an unsafe geometry uranium powder storage hopper. In all three cases, the inspectors determined that the licensee had correctly characterized the occurrence as non-reportable. There was no evidence that the licensee was evaluating the reportec: issues for broader trends because no special corrective actions were identified in the areas where multiple repor's had been made.
14 CONCLUSIONS The audit and inspection program appeared adequate in generating findings and observations, but that corrective actions were not developed, assigned, or tracked to closure. The inspectors found that there were also numerous and repetitive violations of administrative limits involving mass contents of hoods and safe slab heights. There was no evidence that the licensee had evaluated these violations for broad issues in the plant. Completion of effective and prompt corrective action and tracking and trending of criticality safety violations are censidered program weaknesses. Because the licensee does not have a specific procedure covering the criteria and methodology for conducting and documenting event investigations, event investigation is also considered a program weakness.
6.0 Criticality Alarm Monitoring Systemn SCOPE The inspectors examined the detectors, alarm logic, coverage, and audibility of the criticality accident alarm system to determine whether the system compied with ANSI /ANS-8.3 and was adequate to perform its safety function in the event of a criticality excursion.
OBSERVATIONS AND FINDINGS The licensee used Eberline Instrument Corporation DA-1 remote detectors, which are Geiger.
Mueller type detectors with two detectors located at each of sixteen positions throughout the plant, Activation of an alarm signal requires that both detectors at a position must alarm, or that one fail and one alarm, or that both fail. Coverage has been determined to be adequate by the licensee using calculations based on the example from Appendix B of ANSl/ANS-8.3.
Calculatior, of coverage in two cases requires the use of build-up factors to reach to alarm trip level. Detector response time is on the order of 4 ps, which meets the ANSl/ANS-8.3 requirement to detect transients with a duration of 1 ms. The system detects a field between 0.01 and 100 mR/hr and the detector set point is 10 mR/hr, which is adequate to detect the minimum accident of concern at the various radii of coverage that exist in the licensee's facility.
Detectors are source checked quarterly and calibrated annually. Maintenance records were adequate. The licensee performs an annual evscuation drill which is initiated using the criticality alarms. An annual evacuation horn audibility test is required by the test procedure, HP 317.00, " Alarm Testing," Section 3.4. The licensee maintains records of audibility tests by room to demonstrate continued audibility of the system. The licensee has not formally committed to comply with ANSI /ANS-8.3, but attempts to conform.
CONCLUSIONS h inspectors determined that criticality alarm coverage, sensitivity, and response is adequate.
There is a program weakness in that the alarm system does not completely comply with ANSI /ANS-8.3, Section 5.4, because a component failure consisting of failure of two detectors at one position will cause an evacuation alarm. The licensee acknowledged the concern and committed to evaluate corrective actions, although changing the system may be difficult due to the fact that the logic is hard-wired.
15 7.0 NCS Emergency Response SCOPE The inspectors reviewed the plant emergency response to determine whether criticality related restrictions on the use of water in fire fighting were incorporated into emergency plans and the implementing procedures, and whether they were effectively communicated to responders.
OBSERVATIONS AND FINDINGS License Application Section 4.2.4(a) requires that water hoses shall not be used to fight fires in the Oxide Building and Paildings 253,254,255,256-1, and 230. The inspectors reviewed Emergency Plan Implementing Procedure (EPIP) 3.01, " Fire / Explosion, to de* ermine whether adequate measures have been taken to preclude the use of water hoses for fire fighting in areas of the plant where moderator is excluded. Section 3.4 of EPIP 3.01 requires that the Fire Department incident Commander be advised that fire hoses are not allowed in the fuel manufacturing buildings. This information is also contained in Attachment A, which is used to brief the arriving Fire Department incident Commander. Section 5.1 of the Pre-Fire Plan also prohibits the use of fire hoses in areas specified on a plan view of the site buildings.
CONCLUSIONS The inspectors determined that incorporation of criticality safety requirements from the license into emergency plans and pre-fire plans was adequate.
8.0 Followup of Previous inspection Findings VIO 70-0036/96 202-01
' This violation concemed failure to evaluate modifications to the retention hopper above the UO, screw cooler and changes to the reactor vessel dimensions in the Oxide Conversion Facility in 1996. The lower portion of the reactor vessel was changed from 10" to 12" diameter, giving the reactor a uniform diameter of 12" along its entire length. The inspectors reviewed the new evaluation of the R2 retention hopper and reactor vessel and determined that it contained the required analysis (See Section 1.0). This violation is now closed.
VIO 70-0036/96-202-02 This violation concerned failure of the change control review procedure to require establishing or updating of maintenance, surveillance, and functional testing requirements. The inspectors reviewed the change control procedure (See Section 3.0) and now consider this item closed.
IFl 70-0036/96-202-03 This IFl concerned potential common mode failures of dual sampling used to control fissile content of solution prior to transfer from the Filtrate Hold Tanks to the Filtrate Processing Tanks in the Recycle Recovery Room. During Inspection 96-202, the inspectors determined that there
16 was only a single sample drawn to venfy solution concentration. The inspectors thus reviewed procedure O.S. 051.00, " Filtrate Processing," dated November 11,1997. Although the procedure requires two samples to be drawn, and the tank to be agitated for thirty minutes between the two samples, the inspectors determined that there was still the potential for common mode failure in that a single operator takes both samples, and thus could bias both samples with a single error. The operator could also neglect to agitate the tank between samples. The inspectors then examined the laboratory procedure for analyzing the sample results. The inspectors determined that the sample 3 are analyzed by a single laboratory analyst on a single gamma counter, and thus the analysis was also subject to common mode failure. The licensee responded that the analyst is required to run a standard between analysis of the two samples, and at the beginning and end of each shift. However, both measurements could be subject to the same bias in the event that the analyst neglects to run the standard between the samples. Because neither the operator's nor the analyst's activities are supervised, the i' 3pendence of the two samples would be compromised by a single error.
Because Licens. .pplication Section MA icquires two independent methods of controlling fissile material transfer to unfavorable geometry, and because there are no other identified controls on solution concentration, this item is VIO 70-0036/98 201-10.
"he inspec ors determined that there was no immediate safety issue because the filter presses
-t the centrifuge upstream typically minimize the amount of fissile materist in the aqueous s.,eam. The licensee did not agree that the sampling was subject to common-mode failure.
URI 70-0036/96 202-04 This URI concerned sufficiency of NCS training provided to production supervisors. The inspectors determined that procedure RAAP-119, " Regulatory Affairs Training," Rev. O, adequately addressed the training requirements for production supervisors. Since the licensee indicated that all production supervisors had completed the required course, this item is now considered closed.
VIO 70 0036/96-202-05 This violation concerned improper labeling of mass-limited containers throughout the plant. The inspectors observed during a plant walk-through that mass-limited containers were marked according to their mass and enrichment, and that empty containers were labeled as such.
Requirements to label these containers are contained in MC&A procedure MC&A-415, " Material Storage in Alternate Multipurpose Array or Container," and procedure RAAP-110, "Intemal Audits and Inspections " Rev. O, requires containers and labels to be checked during quarterly audits. This item is new closed.
IFl 70-0036/96-202-06 This IFl concerned followup of long-term corrective actions from the Erbia Grinding Station Bulletin 91-01 investigation. The inspectors determined during a walk-through that plexiglass panels had been installed in most of the unfavorable geometry vessels, so that an accumulation of material would be readily observable. This equipment included all grinding stations. This item is now considered closed.
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17 lFI 70-0036/96-202-07 This IFl concerned review of the Integrated Safety Analysis (ISA) to ensure that the Hazard Analysis was performed using up-to-date drawings and piping-and-instrumentation diagrams (flow diagrams). The inspectors reviewed the ISA Supplement issued May 30,1997, and verified that it referenced up-to-date drawings and flow diagrams. The inspectors examined the drawings and diagrams and noted that they contained a stamp which indicated they had been reviewed for parameters important to criticality safety by NCS. This item is now closed.
I I IFl 70-0036196 202-08 This IFl concerned the lack of a methodology for reporting functional test failures to management in a timely manner. The inspectors reviewed maintenance procedure OS 4101, which required review of all functional test results by Regulatory Affairs. Since this should ensure that all test failures are promptly directed to management, this item is now closed.
) IFl 70-0036/96 202-09 l
This IFl concemed review of the licensee's actions to address 1995 Annual Audit findings and recommendations. The inspectors determined that there are corrective actions from subsequent annual audits that have not been resolved, and so this item remains open.
9.0 Exit Meeting An exit meeting was held between NRC Headquarters staff and plant management on January 16,1998. No proprietary or classified information was discussed.
18 ITEMS OPENED. CLOSED. OR DISCUSSEQ 11 ems Ooened (docket 70-0036) 98-201-01 IFl Inconsistencies between license and RAAP-109.
98-201-02 URI Inadequate analysis of UO, cooler.
98-201-03 URI Inaccurate and incomplete information to NRC.
98-201-04 IFl Review of documentation of Safe Individual Units.
98-201-05 NCV Unapproved and unreviewed postings.
98-201-06 NCV Violation of moisture certification on oxide cans.
98-201-07 IFl Use of out-of-date administrative procedures / forms.
98-201-08 IFl Review of training records.
98-201-09 IFl Use of criticality violation reporting system.
98-201-10 VIO Failure to establish dual independent sampling.
i Items Closed 96-202-01 VIO Unevaluated modification to retention hopper and reactors.
96-202-02 VIO Incorporation of maintenance and testing in change control proc.
96-202-04 URI Trainir.g of production supervisors.
96-202-05 VIO Improper labeling of mass-limited containers.
96-202-06 IFl Corrective actions to Erbia Grinding Station incident.
96-202-07 IFl Oxide Conversion ISA supplement.
36-202-08 IFl Reporting of functional test failures to management, items Discussed 96-202-03 IFl Dual sampling of filtrate tanks - carried as Violation 98-201-10.
96-202-09 IFl Actions to address 1995 Annual Audit findings.
PARTIAL LIST OF PERSONS CONTACTED Michael Eastburn Nuclear Criticality Safety Specialist Harold E.' Eskridge NCS Consultant Robert Freeman Nuclear Criticality Safety Specialist Arloh J. Noack Manager, Maintenance Gilles Page Director, Uranium Operations Earl Saito Health Physicist Robert Sharkey Director, Regulatory Affairs Donald E. Underwood Manager, Engineering Philip E. Weaver Manager, Production
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ACRONYMS USED CSPU Criticality Safety Program Update >
EPIP Emergency Plan implementing Procedure
'HP Health Physics IFl Inspector Followup Item ISA Integrated Safety Analysis NCS - Nuclear Criticality Safety NCSE Nuclear Criticality Safety Evaluation NCSS Nuclear Criticality Safety Specialist NCV Non-Cited Violation -
SIU Safo individual Unit URI Unresolved item
- VIO Violation l
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