View source for SVP-97-244, Requests Exemption from Requirements of 10CFR70.14(a), Criticality Accident Requirements, Because Plant Design Bases for Fuel Storage,Handling & Use Preclude Accidental Criticality Event

{{Adams
| number = ML20198N412
| issue date = 10/27/1997
| title = Requests Exemption from Requirements of 10CFR70.14(a), Criticality Accident Requirements, Because Plant Design Bases for Fuel Storage,Handling & Use Preclude Accidental Criticality Event
| author name = Pearce L
| author affiliation = COMMONWEALTH EDISON CO.
| addressee name = 
| addressee affiliation = NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
| docket = 05000254, 05000265
| license number = 
| contact person = 
| document report number = SVP-97-244, NUDOCS 9711040169
| document type = CORRESPONDENCE-LETTERS, INCOMING CORRESPONDENCE
| page count = 7
| project = 
| stage = Other
}}

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        **     Quad Citin Generating Matson -
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                - SVP 97-244 October 27,1997 -
s U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Attention:       Document Control Desk

==Subject:==
Quad Cities Station Units 1 and 2 Request For Exemption from 10CFR 70.24 In Accordance With 10CFR 70.24(d) and 10CFR 70.14(a)
Criticality Accident Requireraents NRC D_ockets 50-254 and 50-261

==References:==
(a)      R. M. Pulsifer letter to I. Johnson dated September 24,1997,
                                            " Criteria For An Exemption From the Requirements of 10 CFR 70.24 - Quad Cities Nuclear Power Station, Units I and 2."
(b)    NRC Information Notice 97-77, " Exemptions From the Requirements of Section 70.24 of Title 10 of the Code of Federal Regulations."
                 - Pursuant to 10CFR 70.24(d) and 10CFR 70.14(a), Comed hereby requests an exemption from the requirements of 10CFR 70.24, " Criticality Accident Requirements,"
for Quad Cities Station Units 1 and 2.
10CFR 70.24 requires facilities authorized to possess special nuclear muerial (SNM) to r rovide criticality monitors and r?propriate emergency response procedures to protect personnel during a postulated criticality accident. Nuclear power reactors are governed under regulations contained primarily in 10CFR50.10CFR50, Appendix A, establishes design requirements .o preclude the occurrence of any accidental criticality event.
Comed is requesting an exemptiou from the requirements of 10CFR 70.24 for Quad                                         .
Cities Station because the plant design bases for fuel storage, handling and use preclude an accidental criticality event. Therefore,10CFR 70.24 requires the expenditure of
                  ~ Station resources withcut a significant increase in overall safety.
The basis for this exempt'.on request 'is described in the enclosure which was performed in accordance with the guidance provided in References (a) and (b).
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9711040169 471027 D                                                              h A Unkom Comp m)

USNRC.
SVP-97-244                                   2                          October 27,1997 Comed requests NRC approval of this exemption request within three months of receipt of this submittal. If you have any questions coacerning this letter, please contact Charles
                - Peterson, Regulatory Affairs Manager, at (309) 654-2241, extension 3609.
Respectfully, L. W. Pearce Site Vice President -
Quad Cities Nuclear Power Station Attachment A,-10CFR70.24 Exemption Request for Quad Cities Station cc. . A. B. Beach, Regional Administrator, Region III R. M. Pulsifer, Project Manager, NRR C. G. Miller, Senior Resident Inspector, Quad Cities W. D. Leech, MidAmerican Energy Company D. C. Tubbs, MidAmerican Energy Company F. A. Spangenberg, Regulatory Affairs Manager, Dresden INPO Records Center Office of Nuclear Facility Safety, IDNS DCD License (both electronic and hard copies)
M. E. Wagner, Licensing, Comed SVP Letter File e                                         - -

ATI'ACIIMENT A Quad Cities Station Request for Exemption from 10CFR 70.24 Criticality Accident Reauirements SVP-97-244 (Page 1 of 5)
Pursuant to the requirements of 10CFR 70.14(a) and 10CFR 70.24(d), Comed requests permanent exemption from the criticality monitoring requirements specified in 10CFR 70.24 for Quad Cities Station. Title 10CFR 70.24 provides the requiremenh for a monitoring system that will energize clearly audible alarms if accidental criticality occurs in each area in which licensed quantities of special nuclear material (SNM) is handled, used, or stored. In addition,10CFR 70.24 requires that the licensee shall maintain emergency          ,
procedures to ensure that all personnel withdraw to an area of saft.ty when the alarm sounds. These procedures must include the conduct of drills to familiarize personnel with the evacuati on plan, designation of responsible individuals for determining the cause of the alann, and placement of radiation survey instruments in accessible locations for use in such an emergency.
Comed believes that the exemption is technically appropriate because the station design and licensing bases, consistent with the requirements of 10CFR50, Appendix A, preclude an accidental criticality event. General Design Criterion (GDC) 62, Prevention of Criticality in Fuel Storage and Handling, states that criticality in the fuel storage and handling system shall be prevented by physict.1 systems or processes, preferably by use of geometrically safe configurations. In addition, GDC 63, Monitoring Fueland Waste Storage, states that appropriate systems shall be provided in fuel storage and radioactive waste systems and associated handling areas to: (1) detect conditions that may result in
            . excessive radiation levels, and (2) initiate appropriate safety actions. Although Quad Cities is not licensed to GDC 62 and GDC 63, the design of refueling systems and associated radiation monitoring equipment at Quad Cities Station are consistent with these requirements.
j        The specific requirements for granting exemptions from Part 70 regulations are set forth in 10CFR 70.24(d) and 10CFR 70.14(a). Section 70.24(d) anticipates that licensees may need relief from 10CFR 70.24, in whole or in part, if " good cause" is shown. References (a) and (b) provide the NRC's criteria for 10CFR70.24 exemption requests. As further discussed below, Comed believes that " good cause" exists and that the exemption requirements of 10CFR 70.14(a) are satisfied for Quad Cities Station.
EXEMPTION REOUEST l
Under Section 70.14(a), the Cornmission is authorized to grant an exemption to Part 70 i
~
requirements provided the exemption: (a) is authorized by law; (b) will not endanger life, property, or the common defense and security; and (c) is in the public interest. Aa               l described below, Comed believes the exemption request clearly meets these requirements.
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NITACIIMENT A Quad Cities Station Request for Exemption from 10CFR 70.24 Criticality Accident Requirements SVP-97-244 (Page 2 of 5)
A. Ih3faggpjion Requnt Is Authorized By Law The NRC's authority to grant exemptions from the requirements of Part 70 is codified h 10CFR 70.14(a). Moreover,70.24(d) makes it clear that the NRC has specific and expressed authority to exempt licensees from the requirements of Section 70.24. Therefore, granting the requested exemption for Quad Cities Station is authorized by the NRC's regulations.
B. The Exemplion WillEgilodanger Life or Proorrty The manner in which SNM is used, stored, and handled at Quad Cities Station provides adequate protection for the haalth and safety of the public. Specifically, design characteristics, procedural controls, and analyses ensure that accidental er inadvertent criticality will not occur at Quad Cities Station.
: 1. Use of SNM Non-Fuel SNM Special nuclear material is present principally in the form of nuclear fuel.
However, other quantities of SNM are used (and stored) at Quad Cities Station in the form of fissile material used in fission chamber detectors.
The small quantity of SNM present in these latter items precludes an inadvertent criticality. Comed internal procedures place strict limits on the amount of SNM stored in areas not specifically analyzed for criticality Limiting the amount of SNM to 50g in such areas provides suflicient margin to critical mass as described in 10CFR 150.11. (Ref. b., item 5) lhe of SNM as Nuclear Fuel Undenvater monitoring is not required by 10CFR 70.24 for SNM stored or handled beneath water shielding. Inadvertent or accidental criticality in the reactor vessel is prevented through compliance with the facility Technical Specifications. These Technical Specifications include reactivity requirements (e.g , shutdown margin limits and control rod movement limits), instrumentation requirements (e g., power and radiation monitors),
and controls on refueling operations.
Therefore, the requirements of Section 70.24 are not necessary for the use of SNM, thus, granting this exemption will not endanger life or property.

l KITACIIMENT A Quad Cities Station Request for Exemption from 10CFR 70.24 Criticality Accident Reauirements SVP-97-244 (Page 3 of 5)
: 2. Storage of Fuel SNM as nuclear fuel is stored in one of two locations - the spent fuel pool on the new fuel storage vault. The spent fuel poolis used to store irradiated fuel under water after its discharge from the reactor, or new fuel following receipt. The pool is designed to store the fuel in an array that precludes criticality. In addition, existing licensing basis (Technical Specifications and UFSAR) limit spent fuel pool reactivity such that k.a is maintained less than or equal to 0.95. Criticality analyses have demonstrated that 0.95 konis maintained with a 95/95 confidence level for existing fuel designs at Quad Cities. In addition, administrative controls are in place to ensure future fuel designs will satisfy these criteria.
(Ref. b., Item 4)
Thi new fuel storage vault is used to receive and store new fuel in a dry condition upon arrival on site and prior to use. Internal procedures limit new fuel U-235 enrichment to no more than 5 wt% nominal ennchment. In addition, the fuel vendor's material license limits the enrichment of fuel assemblies to no more thun 5 wt% U-235. The new fuel storage racks are designed to store new fuel in a geometric array that precludes criticality, Criticality analyses have been performed to ensure that k,n is less than or equal to 0.95 (as required by the UFS AR) when the new fuel racks are fully loaded and flooded with pure water with a 95/95 confidence level. In addition, administrative controls are in place to ensure future fuel designs will satisfy thew criteria. (Ref. b., Items 2 and 7) y Quad Cities does not analyze for optimum moderation conditions.
Consistent with industry practice, Quad Cities has implemented administrative and physical controls in accordance with GE SIL 132, Criticality Marginsfor the Storage ofNew Fuel, to preclude the existence of an optimum moderation condition in the new fuel storage vault area.
These controls include: the new fuel storage vault is verified dry, the drains are free and clear of obstruction prior to new fuel storage; low velocity fog nozzles (fire protection) in the vicinity of the dry storage vault have been removed; and the new fuel storage vault plugs are installed during prolonged work delays. (Ref b., Item T Therefore, the requirements of Section 70.24 are not necessary for the fuel stored in the new fuel storage vault or the spent fuel pool, thus, granting this exemption will not endanger life or property.
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ATTACHMENT A                                                                                                     $
Quad Cities Station Request for Exemption from 10CFR 70.24 Criticality Accident Reauirements SVP-97-244 (Page 4 of 5)
: 3. llandling of SNM Nuclect fuel is moved into the facility in metal shipping containers (MSCs).
The fuelis removed from the MSCs and is moved to the new fue inspection stand, the new fuel storage vault, or the spent fuel pool, to prepare for refueling operations. In all cases, fuel movements are procedurally controlled and designed to preclude conditions involving criticality concems. Plant procedures prohibit more than three new fuel assemblies to be in transit between '. heir MSC and the n:w fuel storage vault or spent fuel pool at one time. Limiting the transit of nuclear fuel to three new assemblies is a conservative p;actice because the fuel designs at Quad Cities employ the use of burnable poisons. (Ref. b., item 1)
Therefore, the criticality monitoring requirements of Section 70.24 are not necessary for the safe handling of SNM, thus, granting this ememption will not endanger life or property.
: 4. Monnkgring of ShN
                                 'I ne areas where SNM is handled and stored that requires monitoring for excessive radiation levels are: (a) the new fuel storage vault, and (b) areas on the refuel floor in which new fuel is handled / stored once it is removed from its Part 71 fuel shipping container and prior to being placed mder water in :he spent fuel pool. These areas are consistent with 10Li slo.24 requirements.
Quad Cities Units 1 and 2 has a te'al of four Area Radiation Monitor (ARM) instruments that monitor for excessive radiation levels that are indicative of an accidental criticality event. These ARMS provide low range monitoring of the new fuel storage vault and the following refuel floor areas: the area above the Unit I and 2 spent fuel pools, the equipinent hatch, and areas where new fuel is handled or temporarily stored (e.g., for inspection). These ARMS provide e>ntrol room audible alarms for their respective areas, and appropriate actions are taken to evacuate personnel upon receipt of a high radiation alaru in accordance with Station procedures. Plant procedures ensure the ARMS are operating normally                                                                                                             y prior to handling new fuel. (Ref. b., item 6)
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ATTACIIMENT A Quad Cities Station Request for Exemption from 10CFR 70.24 Criticality Accident Reauirements SVP-97-244 (Page 5 of 5)
Additionally, there are four Technical Specification ARMS on the refuel floor which isolate ventilation and initiate the Standby Gas Treatment System (SGTS) upon detection of a high radiation condition. Each of the eight ARMS described above functions in conjunction with the station's design contro!s for precluding an accidental criticality event.
Therefore, exemption from the criticality monitoiing requirements of Section 70.24 will not endanger life or property.
C.        Ihthemption Request is in the Public Interest The maintenance of a criticality accident monitoring system and program :neeting the requirements of 10CFR 70.24 requires an expenditure of resources without a significant increase in overall safety. These expenses would include edditional administrative controls, and the planning and conducting of drills specifically designed to respond to a criticality accident. Monitoring based on the guidance in 10CFR 70.24 is unnecessary because the Quad Cities Station design and licensing bases preclude an accidental criticality consistent with the requirements of       ,
10CFR50 Appendix A, General Design Criteria For Nuclear Power Plants. The resources required to maintain an accidental criticality system in accordance with 10CFR 70.24 could be better used to augment the safe operation of the plant in other areas. Consequently, the exemption request is in the public interest.
CONCLUSION As discussed above, an exemption from the requirements of 10CFR 70.24 for Quad Cities Station is authorized by law, will not endanger life or property or the common defense and     .
security, and is in the public interest. An exemption from 10CFR 70.24 for Quad Cities Station is technically appropriate because the plant design basis features for fuel storage, use, and handling preclude an accidental criticality event; therefore, the requirements of 10CFR 70.24 do not provide a significant increase in overall plant safety. This is ensured by the use of refueling controls and design features, and radiation monitoring systems that are consistent with the requirements of the 10CFR50 Appendix A General Design Criterion.
Fcr these reasons, Comed believes the specific requirements for granting an exemption from 10CFR 70.24 have been met and respectfully requests the NRC to grant the exemption for Quad Cities Station.
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