ML20085E612
| ML20085E612 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 06/09/1995 |
| From: | Debarba E NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20085E615 | List: |
| References | |
| B15215, NUDOCS 9506190042 | |
| Download: ML20085E612 (8) | |
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1 \ Northeast 107 Se1 dea 8'raet, neriin, er 06037 U g Utilities System Northe t utilitie. service company P.O. Box 270 Ifortford, CT 06141-0270 (203) 665-5000 June 9, 1995 Docket No. 50-423 315215 Re: 10CFR50.90 6
U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Millstone Nuclear Power Station, Unit No. 3 ,
Proposed Revision to Technical Specification :
Secondary Containment Introduction ,
Pursuant to 10CFR50.90, Northeast Nuclear Energy Company (NNPCO) hereby proposes to amend its operating License, NPF-49 by incorporating the changes identified in Attachments 1 and 2 into the Millstone Unit No. 3 Technical Specifications. Specifically, Surveillance Requirement 4.6.6.1.d.3 for attaining a negative pressure in the secondary containment is being relocated to Specification 3.6.6.2, Secondary containment. The Action Statement of Section 3.6.6.1 has been revised to decouple Sections 3.6.6.1 and 3.6.6.2.
In addition, Definition 1.12, " Secondary Containment Boundary" is being deleted and included in the Bases Section 3/4.6.6, 3 Secondary Containment.
Bases Section 3/4.6.6.2, Secondary containment is being expanded using the guidance of the improved standard technical specifications (STS) for Westinghouse plants (NUREG-1431).
Background
There have been planned breaches of the secondary containment boundary above and beyond normal everyday personnel passage through the doorways over the operating life of Millstone Unit No. 3. In each case, the Action Statement of Limiting condition of Operation (LCO) 3.6.6.2 was entered. The Action Statement ;
requires that the operability of the secondary containment i boundary be restored within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or be in at least Hot Standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
On. March 22, 1995, with the plant in Mode 1 at 100 percent power, -
a prompt report was made that there were historical planned ;
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i breaches of the secondary containment boundary. This condition -
was later reported in Licensee Event Report (LER)W 95-004-00.
During the periods of secondary containment boundary breach, the ,
effectiveness of the supplementary leak collection and release f system (SLCRS) was reduced, and most likely in some instances, 1 the drawdown of the secondary containment boundary to a negative pressure of 0.4 inch water gauge within 120 seconds (measured at !
the 24'-6" elevation of the Auxiliary Building) would not have i been possible. This once per 18-month surveillance test is +
required to prove the operability of the system in accordance j with Technical Specification 3.6.6.1. and would most likely not i
have been successful if performed concurrent with the existence of the larger breaches. None-the-less, the system would still ,
have been effective in reducing the levels of radionuclides !
released to the outside environment due to a negative pressure )
inside the building. -
Thus, while the plant has historically entered into the Action Statement of LCO 3.6.6.2 (i.e., 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Action Statement) when !
there were planned breaches (i.e., above and beyond the normal ;
everyday personnel passage through doorways), the presence of i these planned breaches has recently identified a conflict I relative to meeting the SLCRS operability requirements. ,
specifically, the ability to (in conjunction with the auxiliary !
building filter system (ABFS)] establish and maintain a negative i' pressure of 0.4 inch water gauge measured at elevation 24'-6" in the Auxiliary Building, was reduced. The current technical l specification for Millstone Unit No. 3 is based on an old j Westinghouse STS (i.e., NUREG-0452). A specific interpretation :
of the SLCRS Technical Specification (Section 3.6.6.1), as !
currently written, would have resulted in an entry into Technical Specification 3.0.3, requiring a plant shutdown for any planned t breach. It is noted that the NRC Staff has recognized this j situation (i.e., cascading effect of technical specifications ,
that requires entering additional action statements for supported i systems or other systems that were also affected) and the l correction to this is reflected in the new, improved STS for !
Westinghouse plants (NUREG-1431). Specifically, NUREG-1431 has removed the drawdown requirement (i.e., surveillance requirement for attaining a negative pressure in the secondary containment) from the filtration technical specification (SLCRS Technical .
Specification 3.6.6.1 in our case) and relocated this material to l the Secondary Containment Boundary Technical Specification (1) D. B. Miller letter to' the U.S. Nuclear Regulatory Commission, " Licensee Event Report 95-004-00," dated April 21, 1995.
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(Section 3.6.6.2 in our case). This change in NUREG-1431 recognizes the direct impact of boundary integrity on drawdown capability. NNECO has determined that the Millstone Unit No. 3 ,
Technical Specifications need to be modified to resolve this l and conflict between Specifications 3.6.6.1 3.6.6.2 and, therefore, NNECO is proposing changes to the Millstone Unit No. 3 Technical Specification, Section 3.6.6.1, 3.6.6.2, and 3.6.6.3.
DescriDtion of Proposed Chances The secondary containment drawdown requirement is presently located in Specification 3.6.6.1, Supplementary Leak Collection and Release System. Specifically, Surveillance Requirement 4.6.6.1.d.3 verifies that one of the trains of SLCRS in conjunction with the ABFS will produce a negative pressure of 0.4 inch water gauge in the Auxiliary Building at 24'-6" elevation within 120 seconds after a start signal (this includes the diesel generator start and load time of approximately 10 seconds). NNECO is proposing to relocate this surveillance requirement under the secondary boundary technical specification l (i.e., new Surveillance Requirement 4.6.6.2.2). This change will recognize the direct impact of boundary integrity on the drawdown capability and will decouple Specification 3.6.6.1 from Specification 3.6.6.2. In addition, Definition 1.12, " Secondary Containment Boundary" is being deleted and the information related to the term " Secondary Containment Boundary" will be included in the Bases Section 3/4.6.6.2, " Secondary Containment."
Sections 3.6.1.2, 3.6.6.2 and 3.6.6.3 are being revised to reflect the above changes. Action Statement for LCO 3.6.6.1 is being revised to include "with one Supplementary Leak Collection and Release System inoperable, the conditions and required actions associated with Specification 3.6.6.2 are not required to be entered." This statement will decouple Specifications 3.6.6.1 and 3.6.6.2. Bases Section 3/4.6.2.2 has been expanded using the guidance of the improved STS (NUREG-1431). In addition, the Action Statement for LCO 3.6.6.2 has been revised to include:
"while in this Action Statement, the conditions and required actions associated with Specification 3.6.6.1 are not required to be entered," This is because the inoperability of the secondary containment does not make the SLCRS fans and filters inoperable.
Also, Bases Sections 3/4.6.6.1 and 3/4.6.6.3 and Index Pages i and ix are revised to reflect the above changes.
The mark-up of the existing technical specifications is contained in Attachment 1. The retype of the proposed changes to the technical specifications are contained in Attachment 2 and reflect the currently issued version of technical specifications.
i U.S. Nuclear Regulatory Commission B15215/Page 4 June 9, 1995 Safety AssessagAt l
As currently written, the Action Statement for Technical l
Specification 3.6.6.2 requires that in the event the secondary containment boundary operability is not maintained, operability l must be restored within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Whenever there was a breach I (i.e., a normal everyday personnel passage through doorways does i not constitute a breach in the secondary containment boundary) in I the secondary containment boundary, the plant has historically l entered the Action Statement for LCO 3.6.6.2 (and not entered the i Action Statement for LCO 3.6.6.1, SLCRS technical specifications). However, with a change in the interpretation of technical specifications, the plant should have entered additional Action Statements for supported systems or other systems (e.g., SLCRS) that were also affected. The new interpretation for the SLCRS technical specification in conjunction with an entry in the Action Statement for LCO 3.6.6.2 would result in an entry into Technical Specification 3.0.3, requiring a plant shutdown. I The proposed changes to LCO 3.6.1.2, LCO 3.6.6.1 and LCO 3.6.6.2 l Action Statements, relocation of Surveillance Requirement 4.6.6.1.d.3 to Specification 3. 6. 6. 2, changes to Bases Sections 3/4.6.6.1, 3/4.6.6.2, and 3/4.6.6.3 and deletion of definition 1.12 will resolve this conflict between Specifications 3.6.6.1 and 3.6.6.2. Specifically, the requirement to establish and maintain negative pressure of 0.4 inch water gauge at elevation 24'-6" in the Auxiliary Building included in Specification 3.6.6.1 belongs to Specification 3.6.6.2, Secondary Containment.
In the event Secondary Containment operability is not maintained, the Action Statement for LCO 3.6.6.2 requires that Secondary containment operability must be restored within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Twenty-four hours is a reasonable completion time considering the limited leakage design of containment and the low probability of a design basis accident (DBA) occurring during this time period.
Therefore, it is considered that there exists no loss of safety function. This situation was recognized by the NRC Staff and has been rectified in the improved STS for Westinghouse plants (NUREG-1431). The proposed changes to Specifications 3.6.1.2, 3.6.6.1, 3.6.6.2, and 3.6.6.3, and corresponding Bases sections do not modify the LCO or surveillance acceptance criterion, nor do they change the frequency of the surveillances. The proposed changes do not involve any physical changes to the plant, do not alter the way any structure, system, or component functions, and do not modify the manner in which the plant is operated. The proposed changes do not have any adverse impact on the design basis accidents previously analyzed. The proposed changes only resolve the conflict between two specifications, namely 3.6.6.1
U.S. Nuclear Regulatory Commission B15215/Page 5 June 9, 1995 and 3.6.6.2. Therefore, the proposed changes do not pose a condition adverse to safety.
Sicinificant Rasards consideration NNECO has reviewed the proposed changes in accordance with 10CFR50.92 and concluded that the changes do not involve a significant hazards consideration (SHC). The basis for this conclusion is that the three criteria of 10CFR59.92(c) are satisfied. The proposed changes do not involve an SHC because the changes would not:
- 1. Involve a significant increase in the probability or consequences of an accident previously evaluated.
The proposed changes to LCO 3.6.1.2, LCO 3.6.6.1 and LCO 3.6.6.2 Action Statements, relocation of- Surveillance >
Requirement 4.6.6.1.d.3 to Specification 3.6.6.2, changes to Bases Section 3/4.6.6.1, 3/4.6.6.2, and 3/4.6.6.3, and deletion of Definition 1.12 will resolve the conflict that currently exists between Specifications 3.6.6.1 and 3.6.6.2. Specifically, the requirement to establish and maintain a negative pressure in the secondary containment boundary included in Specification 3.6.6.1 belongs to specification 3.6.6.2. In the event Secondary containment operability is not maintained, the Action Statement for LCO 3.6.6.2 requires that Secondary Containment operability must be - restored within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Twenty-four hours is a reasonable completion time considering the limited leakage design of containment and the low probability of a DBA occurring during this time period. Therefore, it is considered that there exists no loss of safety function.
The proposed changes do not modify the LCO or surveillance acceptance criterion, nor do they change the frequency of the surveillances. The proposed changes do not involve any physical changes to the plant, do not alter the way any structure, system, or component functions. Therefore, the structures, systems, or components will perform their intended function when called upon. The proposed changes do not affect 'the probability of any previously evaluated accident. Additionally, the proposed changes are consistent with the new, improved STS for Westinghouse plants (NUREG-1431).
Based on the above, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.
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- 2. Create the possibility of a new or different kind of I accident from any accident previously evaluated.
The proposed changes do not make any physical or operational changes to existing plant structures, systems, or components. The proposed changes do not introduce any new failure modes. The proposed changes simply resolve a conflict which currently exists between Specifications 3.6.6.1 and 3.6.6.2. Thus, the proposed changos do not create the possibility of a new or different kind of ,
accident _from any accident previously evaluated. i
- 3. Involve a significant reduction in a margin of safety.
The proposed changes do not have any adverse impact on the accident analyses. Also, the proposed changes resolve a conflict which currently exists between Specifications 3.6.6.1 and 3.6.6.2. The structures, systems, or components covered under Specifications 3.6.6.1 and 3.6.6.2 will i performed their intended safety function when called upon. j Based on the above, there is no significant reduction in the margin of safety. j The Commission has provided guidance concerning the application of the standards of 10CFR50.92 by providing certain examples (51 FR 775), March 6, 1986) of amendments that are not considered likely to involve an SHC. While proposed changes are 'not enveloped by any of the examples, NNECO has demonstrated that the changes do not involve an SHC.
Environmental Considerations NNECO has reviewed the proposed license amendment against the criteria of 10CFR51.22 for environmental considerations. The proposed changes do not increase the types and amounts of effluents that may be released offsite, nor significantly increase individual or cumulative occupational radiation exposures. Based on the foregoing, NNECO concludes that the proposed changes meet the criteria delineated in 10CFR51.22(c) (9) for categorical exclusion from the requirements for an environmental impact statement.
Muclear safety Assessment Board Review The Nuclear Safety Assessment Board has reviewed and concurred with the above determinations.
U.S. Nuclear Regulatc,ry Commission B15215/Page 7 June 9, 1995 jltate Motification In secordance with 10CFR.91(b), we are providing the State of Connecticut with a copy of this proposed amendment to ensure their awareness of this request.
Schedule Reauired for MRC Ancroval As discussed in LER 95-004-00, until the proposed changes are approved by the NRC, NNECO will continue to comply with the most restrictive interpretation of the Millstone Unit No. 3 Technical Specifications whenever a normal breach of secondary containment occurs. Hence, we request that the Staff review this proposal in an expedited fashion with the amendment effective as of the date of issuance, to be implemented within 60 days of issuance.
If the NRL Staff should have any questions regarding this submittal, , lase contact Mr. R. G. Joshi at (203) 440-2080. We will prompt., provide any additional information the NRC Staff may need to respond to this request, and we appreciate your efforts in support of this requast.
Very truly yours, NORTHEACT liUCLEAR ENERGY COMPANY FOR: J. F, Opeka Executive Vice President BY: x E ."A . DeBarba Vice President cc: T. T. Martin, Region I Administrator V. L. Rooney, NRC Project Manager, Millstone Unit No. 3 P. D. Swetland, Senior Resident Inspector, Millstone Unit Nos. 1, 2, and 3 Mr. Kevin T.A. McCarthy, Director Monitoring and Radiation Divjsion Department of Environmentd Protection 79 Elm Street P.O. Box 5066 Hartford, CT 06102-5066 I
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'U.S. Nuclear Regulatory Commission B15215/Page 8 June 9, 1995 Subscribed and sworn t before me this 7 day of w , 1995
's > iT~ s-1 Datg Commissio g g r g:
Notary Public
,My Commission Expires December 31.1007
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