ML20029E435
| ML20029E435 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/17/1989 |
| From: | Sniezek J Office of Nuclear Reactor Regulation |
| To: | Jordan E Committee To Review Generic Requirements |
| Shared Package | |
| ML20028G709 | List: |
| References | |
| IEIN-89-051, IEIN-89-51, NUDOCS 9405180289 | |
| Download: ML20029E435 (20) | |
Text
t i
November 17, 1989
!Et:0RANDUM FOR: Edward L. Jordan, Chairman Committee to Review Generic Requirements FROM:
James H. Sniezek, Deputy Director Office of Nuclear Reactor Reoulation
SUBJECT:
PROPOSED BULLETIN ON P0TENTIAL LOSS OF REQUIRED SHUTDOWN MARGIN DURING PEFUELING CPERATIONS We had previously issued Information Notice No. 89-51, dated May 31, 1989, to immediately alert all power reactor licensees to the potential loss of required shutdown margin during refueling.
This Information Notice was the result of a 10 CFR Part 21 notice issued by Baltimore Gas and Electric Company on March 15, 1989, regarding the potential loss of shutdown margin during refueling operations at its Calvert Cliffs Nuclear Power Plant, Units 1 and 2.
Because many power reactors are similarly affected by the potential loss of required shutdown margin during the movement and placement of hiahly reactive fuel during refueling operations, actions should be taken to preclude these l
configurations. The staff has determined that a Rulletin, as provided in, is required to adequately address this concern.
The proposed Bulletin is submitted under Section 111 D of the CRGR Charter as a Category I requi rement. No staf f review guidance or inspection guidance is needed to assure adequate implementation of the actions in the Bullatin.
A CRGR package has been prepared and provided as Enclosure 2.
This package also provides the justification for the information request as reouired by 10 CFR 50.54(f).
A CRGR meeting to consider this Bulletin has been scheduled for November 20, 1980 5
James H. Sninzek, Deputy Director Office of Nuclear Reactor Regulation
Enclosures:
As stated cc w/ enclosures:
See next page
Contact:
Laurence 1. Kopp, NRR (301)492-0879 N. Prasad Kadambi, NRR OGC
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OMB No.:
NRCB No.: 89-UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION WASHINGTON, D.C. 20555 November
, 1989 NRC BULLETIN NO. 89-POTENTIAL LOSS OF REQUIRED SHUTDOWN MARGIN DURING REFUELING OPERATIONS Addressees:
All holders of operatine licenses or construction pennits for pressurized water reactors.
Purpose:
This bulletin is being provided to alert addressees to the potential loss of reauired shutdown margin during the movement and placement of highly reactive fuel during refuelir.g operations.
It is expected that recipients will take the actions in this bulletin to prevent potential violations of required shutdown margin and, in extreme cases, inadvertent criticality during refueling. A response on the requested actions of this bulletin is required within 30 days nf its issuance.
Description of Circumstances:
Baltimore Gas and Electric Company (BGliE) submitted a 10 CFR Part 21 report to the NRC on March 15, 1989, reg &rding the potential loss of shutdcwn margin during refueling operations at its Calvert Cliffs Nuclear Power Plant, Units 1 and 2.
BG&E reported that it had increased the fuel enrichment during the last several fuel cycles, in the current cycle. 4.3 weight percent U-235 fuel was loaded into the core. During a review of NRC Information Nntice No.
88-21, " Inadvertent Criticality Events at Oskarshamn and U.S. Muclear Power Plants," EGLE discovered that the Calvert Cliffs refueling procedures allowed the placement of fuel assemblies in intermediate positions during core P
I NRCB No.: 89-November
, 1969 Page 2 of alterations.
In addition, BG&E determined that the potential existed for placing several fresh 4.1 weight percent reload assemblies together and losing some of the shutdown margin required by the plant technical specifications.
Calculations also showed that under extreme conditions an inadvertent criticality could occur if a number of highly reactive assemblies were grouped together.
BG&E has revised the Calvert Cliffs refueling procedures to ensure that fuel asserrilies will not be placed in intermediate positions during core alterations without first verifying their potential reactivity. The revised procedures allow fuel to be positionea only in intermediate core locations that will contain fuel of equal or greater reactivity in the final core configuration.
Discussion:
As a result of longer fudl operating cycles, utilities have been increasing the enrichment of reload fuel.
Some of these fresh reload assemblies may be highly reactive under refueling conditions.
Although analyses are perfonned for PWRs to confirm that the refueling boron concentration is sufficient to maintain the required shutdown margin (subcriticality) for the final core configuration, these analyses may not be sufficient to assure that the shutdown margin will be maintained for all intermediate fuel assembly positions.
In eddition, explicit procedural controls may not exist to control the location and moverrent of highly reactive fuel assemblies during refueling. Because a significant ameunt of reactivity can be added to subcritical configurations by the addition of a single highly reactive assembly, it is possible that an inedvertent criticality could occur if a number of such assen>blies are grouped together.
With this hiahly reactive fuel, subcritical multiplication (inverse count rate) may nnt provide adequate warning of an approach to criticality.
Since the reactor vessel is open during refueling, an inadvertent criticality
?
NRCB No.: 89-November
,1989 Page 3 of could result in fuel failures, system damage, and potentially high radiological doses to onsite workers.
Combustion Engineering, Inc. (CE), the nuclear fuel design consultant for Calvert Cliffs, recognized this potential problem and issued an information bulletin regarding shutdown margin during refueling to all utilities with CE-designed plants. These utilities have been advised to review their fuel shuffle procedures that control the location of highly reactive fuel and to be aware that the refueling boron concentration necessary to maintain the required shutdown margin, which is based on the final core configuration, may not be sufficient to assure that their required shutdown margin will be maintained for all intermediate fuel assembly positions.
In circumstances in which explicit analyses are not available.for each intermediate fuel assembly position, CE recommends positioning fuel only in intermediate core locations that will contain fuel of equal or greater reactivity in the final core configuration.
Requested Actions:
Operating Reactors:
All PWR licensees are requested to assure, prior to entry into the next refueling outage, that the potential for loss of required shutdown margin is precisded for all imminent and future core reloads. This may be accomplished by 1.
Assuring that procedural controls are implemented such that all possible intermediate fuel assembly positions during refueling are evaluated with respect to maintaining sufficient refueling boron concentration to result in a minimum shutdown margin of 5% under the most adverse (highest reactivity) control rod configuration allowed during refueling, and
.i NRCB No.: 89-November
, 1989 Page 4 of 2.
Assuring that fuel loading procedures properly account for all evaluated intermediate fuel assembly positions allowed and are strictly followed during refueling.
l Construction Permit Holders:
All PWR construction permit holders are requested to complete the above-listed actions before the date scheduled for fuel loading.
Reporting Reovirements:
Within 30 days of receipt of this bulletin, pursuant to 10 CFR 50.54(f), all holders of OL's for PWRs shall notify the NRC by letter of the steps they have taken, or will take, to (1) evaluate all intermediate fuel assembly positions allowed during refueling to assure that the required shutdown margin is maintained, and (2) assure that fuel loading procedures properly account for all evaluated intermediate fuel assembly positions allowed during refueling.
Prior to initial fuel loading, CP holders shall advise the NRC by letter whether the requested actions have been implemented.
The written reports required above shall be addressed to the U.S. Nuclear Regulatory Commission, ATTN:
Document Control Desk, Washington, D.C. 20555, under oath or affirmation under the provisions of Section 182a, Atomic Energy Act of 1954, as amended and 10 CFR 50.54(f).
In addition, a copy shall be submitted to the appropriate Regional Administrator.
1 i
j l
l
.i NRCR No.: 89-November
, 1989 Page 5 of This reauest is covered by Office of Management and Budget Clearance Number 3150-0011 which expires December'31, 1989.
The estimated average burden hours is 100 person-hours per licensee response, including assessment of the new.
recommendations,. searching data sources, gathering and analyzing the data, and preparing the required letters. These estimated average burden hours pertain only to these identified response-related matters and do not include the time for actual implementation of the requested actions.
Send comments regarding j
this burden estinate or any other aspect of this collection of information, including suggestions for reducing this burdsn, to the Information and Records Management Branch, Division of Information Support Services, Office of Inf ormation Resources Management, U.S. Nuclear Regulatory Commission, Washington, D.C. 20555; and to the Paperwork Reduction Project (3150-0011),
Office of Mantgement and Budget, k!ashington D.C. 20503.
If you have any questions about this matter, please contact the technical contacts listed below or the Regional Administrator of the appropriate regional office.
1 Charles E. Rossi, Director Division of Operational Events Assessment Office of Nuclear Reactor Regulation Technical Contacts:
Laurence I. Kopp, NRR (301) 492-0879 N. Prasad Kadambi, NRR (301)492-1153 i
0 ENCLOSURE 2 CRGP REVIEW PACKAGE PROPOSED ACTION:
Issue a Bulletin with guidance on actions to be taken to prevent potential loss of required shutdown margir. durinq refueling operations.
CATEGORY:
1 RESPCNSE TO REQUIREMENTS FOR CONTENT OF PACKAGE SUBMITTED FOR CRGP REVIEW (i)
The proposed generic requirement or staff position as it is proposed i
to be sent out to li er: sees.
t Staff position is:
l
\\
A proposed Bulletin that will be sent to all PVR licensees and applicants.
It informs licensees and applicants of the potential for 1
the loss of required shutdown margin during refueling caused by
~
possible inadequate refueling procedures that allow intermediate 4
l refueling configurations that are unanalyzed and requires actions to l
be taken to assure that all intermediate fuel configurations allowed i
are adequately evaluated and properly accounted for in the plant fuel loading procedures.
)
(ii)
Draft staff papers or other underlying staff documents supporting the requirements or staff positions.
10 CFR 50.59 This section of, the regulations describes the circurrstances that determine a finding of en unreviewed safety question and states the reporting rcouirements that are necessary.
Refuelina Roron Concentration Technical Specification The minimum boron concentration during refueling is required by technical specificatiens to maintain an adequate shutdown margin whenever the reactor vessel head closure bolts are less than fully tensioned or when the head is removed.
Information Notice 89-51 The information notice inforts all power reactor licensees and applicants of the potential loss of required shutdown margin during ref ueling operations and, in extreme cases, inadvertent criticality with the reactor vessel open.
(iiii Each croposed requirement or staff position shall contain the sponsuring office's position as to whether the proposal would increase requirements or staf f positions, implement existing requirements or staff positions, or would relax or reduce existing requirerrents or staf f positions.
2 The bulletin would implement existing requirements and staff positions in tiiat it woulif requir'e specTfic actions to be taken to assure that the required shutdown margin is maintained during the movement and placement of fuel during refueling operations.
(iv)
The proposed method of implementation with the concurrence (and any comments) of OGC on the method proposed.
The requirements of the bulletin would be implemented promptly by assuring that the effects of all fuel configurations during refueling are evaluated with respect to required shutdown margin. 0GC has no legal objection to this proposal and their comments were incorporated.
(v)
Regulatory analyses conforming to the directives and guidance of NUREG/BR-0058 and NUREG/CR-3568.
A formal regulatory analysis is not required because the issuance of the bulletin is justified on the basis of providing adequate protection to the health and safety of the public pursuant to 10 CFR 50.109a(4)(ii). The actions proposed by the bulletk would maintain current regulatory criteria on required shutdown margin. Not taking the actions proposed by the bulletin may result in violation of the shutdown margin required during refueling and in extreme cases may result in advertent criticality with potential fuel failures, reactor damage, and relatively high radiological doses to onsite workers.
(vi)
Identification of the category of reactor plants to which the generic requirement or staff position is to apply.
This guidance is applicable to all PWRs.
(vii)
For each such category of reactor plants, an evaluation which demonstrates how the action should be prioritized and scheduled in light of other ongoing regulatory activities.
The evaluation shall document for consideration information available concerning any of the following factors as may be appropriate and any other information relevant and material to the proposed action:
(a) Statement of the specific objectives that the proposed action is designed to achieve; margin required during refueling operations is not violated and [)
The proposed action is being taken to ensure that the shutdown
,h that, in the extreme, inadvertent criticality with possible
.y fuel failures and potentially high radiological doses will not
- ' q occur.
The proposed action also ensures that the requirements of the refueling boron concentration technical specification are met.
3 (b) General description of the activity that would be required by the licensee or applicant in order to complete the action; The licensees would have to evaluate each allowed fuel configuration during refueling with respect to maintaining the required shutdown margin and assure that fuel loading l
procedures properly account for all evaluated intersediate configurations and are strictly followed.
(c) Potential change in the risk to the public from the accidental release of radioactive material; The actions required by the proposed bulletin would protect the public against the risk of fuel failures caused by possible inadvertent criticality while the reactor vessel is open.
g (d) Potential impact on radiological exposure of facility employees and other onsite workers.
The actions required by the proposed bulletin would reduce the risk to facility employees and onsite workers by reducing the risk of fuel failures caused by possible inadvertent criticality while the reactor vessel is open.
(e)
Installation and continuing costs associated with the action, including the cost of facility downtime or the cost of construction celay The cost of evaluating refueling loading patterns is not presently known but is not judged to be significant.
i (f) The potential safety impact of changes in plant or operational con'plexity, including the relationship of proposed and existing regulatory requirernents and staf f positions; Any increase in operational complexity is justified on the i
basis of adequately protecting public health and safety.
(g) The estimated resource burden on the NRC associated with the proposed action and the availability of resources; The resource burden to the NRC would be minimal.
J (h) The potential impact of differences in facility type, design or age on the relevancy and practicality of the proposed action; The guidance in the proposed bulletin is applicable only to pWRs because BWRs do not shuffle fuel within the core curing refueling.
(
I' 4
(i) Whether ti. proposed action is interim or final, and if interim, the justification for imposing the proposed action on an interim basis.
This is the final staff position.
Future staff actions will i
ensure that the technical specifications for all PWRs are consistent with this position.
(viii)
For each evaluation conducted pursuant to 10 CFR 50.109, the proposing Of fice Director's detemination, together with the rationale for the determination based on the consideration of j
paragraph (1) and (vii) above, that:
l (a) There is reasonable increase in the overall protection of public health and safety or the common defense and security to be oerived from the proposal; and l
(b) The direct and inairect costs of implementation, for th" facilities affected, are justified in view of this increased protection.
The guidance in the proposed bulletin corrects.a possible deficiency in refueling procedures, and thereby provides for overall protection of public health and safety. The direct and indirect costs of implementation are not considerations applicable to this bulletin.
lix)
For each evaluation conducted for proposed relaxations or decreases in current requirements or staff positions, the proposing Of fice Director's determination, together with the rationale for the determination based on the considerations or paragraphs-(i) through (vii) above, that:
(a) The public health and safety and the common defense and security would be adequately protected if the' proposed reduction in requirements or positions were implemented; and (b) The cost savings attributed to the action would be substantial enough to justify taking the action.
This proposed bulletin does not relax or decrease current requirements or staff positions.
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WASHINGTON. D. C. 20555 tW a
gv.....f HEMORANDUM FOR:
Edward L. Jordan, Chairman Committee to Review Generic Requirements FROM:
James H. Sniezek, Deputy Director Office of Nuclear Reactor Regulation
SUBJECT:
PROPOSED BULLETIN ON POTENTIAL LOSS OF REQUIRED SHUTDOWN MARGIN DURING REFUELING OPERATIONS We had previously issued Information Notice No. 89-51, dated May 31, 1989, to immediately alert all power reactor licensees to the potential loss of required shutdown margin during refueling.
This Information Notice was the result of a 10 CFR Part 21 notice issued by Baltimore Gas and Electric Company on March 15, 1989, regarding the potential loss of shutdown margin during refueling operations at its Calvert Cliffs Nuclear Power Plant, Units 1 and 2.
Because many power reactors are similarly affected by the potential loss of required shutdown margin during the movement ar,d placement of highly reactive fuel during refueling operations, actions should be taken to preclude these configurations.
The staff has determined that a Bulletin, as provided in
', is required to adequately address this concern. The proposed Bulletin is submitted under Section III D of the CRGR Charter as a Category I requirement. No staff review guidance or inspection guidance is needed to assure adequate implementation of the actions in the Bulletin.
1 A CRGR package has been prepared and provided as Enclosure 2.
This package also provides the justification for the information request as required by 10 CFR 50.54(f).
{
l A CRGR meeting to consider this Bulletin has been scheduled for November 20, 1989.
l James H. Sniezek, Deputy Director Office of Nuclear Reactor Regulation
Enclosures:
As stated cc w/ enclosures:
J. Taylor (17H-1)
J. Conran (15 Cys) (MNBB-3209)
G. Arlotto (6A-4)
D. Ross (NLS-007)
J. Moore (16D-19)
L. Reyes (Region II)
Contact:
Laurence I. Kopp, NRR (301)492-0879 N. Prasad Kadambi, NRR (301) 492-1153 to Enclosure 2
l OMB No.:
3150-0011 NRCB 89-XX UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION WASHINGTON, D.C.
20555 Novenber
, 1989 NRC BULLETIN N0. 89-XX:
POTENTIAL LOSS OF REQUIRED SHUTDOWN MARGIN DURING REFUELING OPERATIONS Addressees:
All holders of operating licenses or construction permits for pressurized water reactors.
Purpose:
This bulletin is being provided to alert addressees to tae potential loss of required shutdown margin during the movement and placement of highly reactive fuel during refueling operations.
It is expected that recipients will take r
the actions in this bulletin to prevent potential violations of required shutdown margin and, in extreme cases, inadvertent criticality during refueling. A response on the requested actions of this bulletin is required within 30 days of its issuance.
Description of Circumstances:
Baltimore Gas and Electric Company (BG&E) submitted a 10 CFR Part 21 report to l
the NRC on March 15, 1989, regarding the potential loss of shutdown margin during refueling operations at its Calvert Cliffs Nuclear Power Plant, Units 1 and 2.
BG&E reported that it had increased the fuel enrichment during the last several fuel cycles.
In the current cycle, 4.3 weight percent U-235 fuel was loaded into the core.
During a review of NRC Information Notice No. 88-21,
" Inadvertent Criticality Events at Oskarshamn and U.S. Nuclear Power Plants,"
i BG&E discovered that the Calvert Cliffs refueling procedures allowed the placement of fuel assemblies in intermediate positions during core alterations.
1 In addition, BG&E determined that the potential existed for losing some of the shutdown margin required by the plant technical specifications, even if several fresh reload assemblies with enrichments as low as 4.1 weight percent were grouped together.
Calculations also showed that under extreme conditions an inadvertent criticality could occur if a number of highly reactive assemblies were grouped together.
BG&E has revised the Calvert Cliffs refueling procedures to ensure that fuel assemblies will not be placed in intermediate positions during core alterations without first verifying their potential reactivity. The revised l
l NRCB 89-XX November xx, 1989 i
Page 2 of 4 i
procedures allow fuel to be positioned only in intermediate core locations i
that will contain fuel of equal or greater reactivity in the final core l
configuration.
f Discussion:
As a result of longer fuel operating cycles, utilities have been increasing the enrichment of reload fuel.
Some of these fresh reload assemblies may be i
highly reactive under certain refueling conditions.
Although analyses are performed for PWRs to confirm that the refueling boron concentration is suf-t ficient to maintain the required shutdown margin (subcriticality) for the final
~
core configuration, these analyses may not be sufficient to assure that the shutdown margin will be maintained for all intermediate fuel assembly posi-4 tions.
In addition, explicit procedural controls may not exist to control the location and movement of highly reactive fuel assemblies dur M refueling.
l Because a significant amount of reactivity can be added to m.*4tical con-i figurations by the addition of a single highly reactive as,:1:.3 it is pos-J sible that an inadvertent criticality could occur if a numbt of such assem-blies are grouped together. With this highly reactive fuel, subcritical multiplication (inverse count rate) may not provide adequate warning of an approach to criticality. An inadvertent criticality could result in fuel failures, system damage, and potentially high radiological doses to onsite workers.
Combustion Engineering, Inc. (CE), the nuclear fuel. design consultant for j
Calvert Cliffs, recognized this potential problem and issued an information bulletin regarding shutdown margin during refueling to all utilities with CE-designed plants.
These utilities have been advised to revice their fuel shuffle procedures that control the location of highly reactive fuel and to be q
3 aware that the refueling boron concentration necessary to maintain the required shutdown margin, which is based on the final core configuration, may not be sufficient to assure that their r quired shutdown margin will be maintained for all intermediate fuel assembly positions.
In circumstances in which explicit
'l analyses are not available for each intermediate fuel assembly position, CE recomends positioning fuel only in intermediate core locations that will contain fuel of equal or greater reactivity in the final core configuration.
1 Requested Actions:
Operating Reactors:
All PWR licensees are requested to assure that adequate shutdown margin is j
maintained during all refueling operations.
This should be accomplished by:
1.
Assuring that any intermediate fuel assembly configuration intended to be used during refueling is evaluated to maintain sufficient refueling boron concentration to result in a minimum shutdown margin of approximately 5%
under the most adverse (highest reactivity) control rod configuration which will occur during refueling and would remain subcritical even if all control rods were fully withdrawn, and
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NRCB 89-XX November xx, 1989 Page 3 of 4 2.
Assuring that fuel loading proced'!res only allow those intermediate fuel assembly configurations that do not exceed the allowable shutdown margin and that these procedures are strictly adhered to.
Construction Permit Holders:
All FWR construction permit holders are requested to complete the above-listed actions before the date scheduled for fuel loading.
Reportina Recuirements:
Within 30 days of receipt of this bulletin, pursuant to 10 CFR 50.54(f), all holders of OLs for PWRs shall notify the NRC by letter whether they have taken, or will take, the actions requested above.
Prior to initial fuel loading, CP holders shall advise the NRC by letter whether the requested actions have been implemented.
The written reports required above shall be addressed to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, D.C. 20555, and shall be submitted under oath or affirmation pursuant tn the provisions of Section 182a, Atomic Energy Act of 1954, as amended and 10 CFR 50.54(f).
In addition, a copy shall be submitted to the appropriate Regional Administrator.
Backfit Discussion The objective of the actions requested in thit bulletin is to ensure that an adequate shutdown margin is maintained during the movement and placement of fuel during refueling operations and to ensure that the requirements for refueling boron concentration contained in the technical specifications for certain plants are met.
The issuance of the bulletin is justified on the basis of the need to provide adequate protection to the health and safety of the public and is consistent with the provisions of 10 CFR 50.109a(4)(ii).
The actions proposed by the bulletins, will ensure tMt an adequate shutdown margin is maintained.
Failure to take tnese actions may result in an inadequate shutdown margin during refueiing operations.
In extreme cases this could result in inadvertent criticality with potential for fuel failures, reactor damage, and relatively high radiological doses to onsite workers.
This request is covered by Office of Management and Budget Clearance Number 3150-0011 which expires December 31, 1989. The estimated average burden hours is 100 person-hours per licensee response, including assessment of the new recommendations, searching data sources, gathering and analyzing the data, and preparing the required letters.
These estimated average burden hours pertain only to these identified response-related matters and do not include the time for actual implementation of the requested actions.
Send comments regarding this burden estimate or any other aspect of this collection of information,
NRCB 89-XX November xx, 1989 Page 4 of 4 including suggestions for reducing this burden, to the Information and Records Management Branch, Division of Information Support Services, Office of Information Resources Management, U.S. Nuclear Regulatory Commission, Washington, D.C. 20555; and to the Paperwork Reduction Project (3150-0011),
Office of Management and Budget, Washington D.C. 20503.
If you have any questions about this matter, please contact the technical contacts listed below or the appropriate NRR project manager.
Charles E. Rossi, Director Division of Operational Events Assessment Office of Nuclear Reactor Regulation Technical Contacts: Laurence I. Kopp, NRR (301) 492-0879
)
N. Prasad Kadambi, NRR (301)492-1153
Attachment:
List of Recently Issued NRC Bulletins O
ENCLOSURE 2 CRGR REVIEW PACKAGE PROPOSED ACTION:
Issue a Bulletin with guidance on actions to be taken to prevent potential loss of required shutdown margin during refueling operations.
CATEGORY:
1 RESPONSE TO REQUIREMENTS FOR CONTENT OF PACKAGE SUBMITTED FOR CRGR REVIEW (i)
The proposed generic requirement or staff position as it is proposed to be sent out to licensees.
Staff position is:
A proposed Bulletin that will be sent to all PWR licensees and applicants.
It informs licensees and applicants of the potential for the loss of required shutdown margin during refueling caused by possible inadequate refueling procedures that allow intermediate refueling configurations that are unanalyzed and requires actions to be taken to assure that all intermediate fuel configurations allowed are adequately evaluated and properly accounted for in the plant fuel loading procedures.
(ii)
Draft staff papers or other underlying staff documents supporting the requirements or staff positions.
10 CFR 50.59 This section of the regulations describes the circumstances that determine a finding of an unreviewed safety question and states the reporting requirements that are necessary.
Refueling Boron Concentration fechnical Specification The minimum boron concentration during refueling is required by most current technical specifications to maintain an adequate shutdown margin whenever the reactor vessel head closure bolts are less than fully tensioned or when the head is removed.
However, some plants, in fact, do not have specified restrictions in their technical specifications.
Information Notice 89-51 The information notice informs all power reactor licensees and applicants of the potential loss of required shutdown margin during i
refueling operations and, in extreme cases, inadvertent criticality with the reactor vessel open.
(iii)
Each proposed requirement or staff position,shall contain the sponsoring office's position as to whether the proposal would increase requirements or staff positions, implement existing requirements or staff positions, or would relax or reduce existing requirements or staff positions.
2 The bulletin would implenent existing requirements and staff positions in that it would require specific actions to be taken to assure that the required shutdown margin is maintained during the movement and plac eent of fue, during refueling operations.
(iv)
The proposed method of implementation with the concurrence (and any comments) of OGC on the method proposed.
The requirements of the bulletin would be implemented promptly by assuring that the effects of all fuel configurations during refueling are evaluated with respect to required shutdown margin. OGL has no legal objection to this proposal and their comments were incorporated.
(v)
Regulatory analyses conforming to the directives and guidance of NUREG/BR-0058 and NUREG/CR-3568.
A formal regulatory analysis is not required because the issuance of the bulletin is justified on the basis of providing adequate protec-tion to the health and safety of the public pursuant to 10 CFR 50.109a(4)(ii). The actions proposed by the bulletin would maintain current regulatory criteria on required shutdown margin.
Not taking the actions proposed by the bulletin may result in violation of the shutdown margin required during refueling and in extreme cases may result in inadvertent criticality with potential fuel failures, reactor damage, relatively high radiological doses to onsite workers, and potential exposure to the public.
(vi)
Identification of the category of reactor plants to which the generic requirement or staff position is to apply.
This guidance is applicable to all PWRs.
(vii)
For each such category of reactor plants, an evaluation which demonstrates how the action should be prioritized and scheduled in light of other ongoing regulatory c*hities.
The evaluation shall document for consideration information available concerning any of the following factors as may be appropriate and any other information relevant and material to the proposed action:
(a) Statement of the specific objectives that the proposed action is designed to achieve; The proposed action is being taken to ensure that adequate shutdown margin is provided during refueling operations to prevent inadvertent criticality.
j i
3 (b) General description of the activity that would be required by the licensee or applicant in order to complete the action; The licensees would have to evaluate each allowed fuel configuration during refueling with respect to maintaining the required shutdown margin and assure that fuel loading procedures properly account for all evaluated intermediate configurations and are strictly followed.
(c) Potential change in the risk to the public from the accidental release of radioactive material; The actions required by the proposed bulletin would protect the public against the risk of fuel failures caused by possible inadvertent criticality while the reactor vessel. is open.
(d) Potential impact on radiological exposure of facility employees and other onsite workers.
The actions required by the proposed bulletin would reduce the risk to facility employees and onsite workers by reducing the risk of fuel failures caused by possible inadvertent.
criticality while the reactor vessel is open.
j (e)
Installation and continuing costs associated with the action, I
including the cost of facility downtime or the cost of i
construction delay; This action is not expected to incur additional cost.
(f) The potential safety impact of changes in plant or operational complexity, including the relationship of proposed and existing regulatory requirements and staff positions; This requirement is not expected to result in significant i
increased operational complexity.
(g) The estimated resource burden on the NRC associated with the proposed action and the availability of resources; The resource burden to the NRC would be minimal.
(h) The potential impact of differences in facility type, design or age on the relevancy and. practicality.of the proposed action;.
The guidance in the proposed bulletin is applicable only to PWRs because BWRs do not shuffle fuel within the core during refueling.
4 (i) Whether the proposed action is interim or final, and if interim, the justification for imposing the proposed action on an interim basis.
This is the final staff position.
Future staff actions will ensure that the technical specifications for all PWRs are consistent with this position.
(viii)
For each evaluation conducted pursuant to 10 CFR 50.109, the proposing Office Director's determination, together with the rationale for the determination based on the consideration of paragraph (i) and (vii) above, that:
(a) There is reasonable increase in the overall protection of public health and safety or the common defense and security to be derived from the proposal; and (b) The direct and indirect costs of implementation, for the facilities affected, are justified in view of this increased protection, l
The guidance in the proposed bulletin corrects a possible deficiency in refueling procedures, and thereby provides for overall protection of public health and safety. The direct and indirect costs of implementation are not considerations applicabie to this bulletin.
(ix)
For each evaluation conducted for proposed relaxations or decreases in current requiremerts or staff positions, the proposing Office Director's determinat. ion, together with the rationale for the determination based on the considerations or paragraphs (i) through (vii) above, that:
(a) The public health and safety and the common defense and security would be adequately protected if the proposed reduction in requirements or positions were implemented; and (b) The cost savings attributed to the action would be substantial enough to justify taking the action.
This proposed bulletin does not relax or decrease current requirements or staff positions.
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1 REMARKS This previous Central File material can now be made publicly available.
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