ML20214S905
| ML20214S905 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 06/01/1987 |
| From: | Mroczka E NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| Shared Package | |
| ML20214S906 | List: |
| References | |
| B12478, NUDOCS 8706100045 | |
| Download: ML20214S905 (4) | |
Text
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June 1,1987 Docket No. 50-245 B12478 Re: 10CFR50.90 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Gentlemen:
Millstone Nuclear Power Station, Unit No.1 Proposed Revision to Technical Specifications Containment Systems Pursuant to 10CFR50.90, Northeast Nuclear Energy Company (NNECO) hereby proposes to amend its Operating License, DPR-21, by incorporating the changes identified in Attachment 1 into the Technical Specifications of Millstone Unit No.
1.
These ch,qnges are consistent with the wording of the original amendment request.W The proposed change will revise Technical Specification Section 3.7. A.6.c, page 3/4 7-8, Containment Systems, Oxygen Concentration, by replacing the phrase "important to safety" with the phrase "necessary to ensure safe plant operation." This change is being requested to eliminate any possible ambiguities associated with the exact definition of the phrase "important to safety", which has been the subject of ongoing NRC and industry consideration and review.(2)
This will in turn facilitate the process of maintaining full compliance with the associated Technical Specification governing drywel! oxygen concentration. In addition, the revision will provide plant operations personnel with maximum flexibility in those inspection and maintenance activities which are necessary to ensure plant safety.
(1)
- 3. F. Opeka letter to 3. / Zwolinski, " Millstone Unit No.1, Proposed Revision to Tefiti 61
,ecifications--Containment Systems," dated May 15,1985.
(2)
NNECO has always interpreted the phrase "important to safety" in the regulations to mean " safety-related." However, the NRC Staff intended the phrase "important to safety" in Technical Specification 3.7.A.6.c. to represent equipment beyond the safety-related set. We have, in the past, interpreted our Technical Specifications consistent with the NRC Staff's intent when License Amendment No.102 was issued. However, since this is contrary to the way we interpret the phras3 "important to safety"in the regulations, we believe it is most appropriate to revise our Technical Specifications, thereby precluding any possible misinterpretation in the future.
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U. S. Nuclear Regulatory Commission B12478/Page 2 June 1,1987 The NRC Staff's safety evaluation which supported the 48-hour period of oxygen concentrations greater than 4% by volume for the purpose of drywell entry for inspection and maintenance activities without reactor shutdown, concluded that the deinerted containment period did not involve a significant increase in the probability or consequences of an accident previously evaluated, did not create the possibility of an accident of a different type than any evaluated previously, and did not involve a significant decrease in the margin of safety.(3)
The proposed change to Technical Specification 3.7.A.6.c will not affect or alter the NRC Staff's safety evaluation conclusion because it does not change the 48-hour period for the deinerted containment considered in the Staff's analysis.
Furthermore, since drywell entry is limited in duration and scope pursuant to the revised Technical Specification, reasonable assurance is provided that the activities authorized will neither reduce reactor safety nor endanger the health and safety of the public.
NNECO has reviewed the attached proposed changes pursuant to 10CFR50.59 and has determined that they do not constitute an unreviewed safety question.
The probability of occurrence or the consequences of an accident or malfunction of equipment important to safety (i.e., safety-related) previously evaluated in the final safety analysis report (FSAR) has not been increased. Additionally, the possibility of an accident or malfunction of a different type than any previously evaluated in the FSAR has not been created. There has also not been a reduction in the margin of safety as defined in the basis for any Technical Specification.
This proposed change clarifies which activities are allowed inside containment during reactor operations, it does not change the forty-eight (48) hour limit of Technical Specification 3.7.A.6.c for drywell oxygen concentration greater than 4% (by volume). The change will enhance operator understanding by using the phrase "necessary to ensure safe plant operation"in place of the more ambiguous phrase "important to safety."
NNECO has reviewed the proposed changes, in accordance with 10CFR50.92, and has concluded that they do not involve a significant hazards consideration in that these changes would not:
1.
Involve a significant increase in the probability or consequences of an accident previously evaluated, as this change serves to clarify which activities are allowed inside containment during reactor operations.
It does not change the 48-hour limit of Technical Specification 3.7.A.6.c for drywell oxygen concentration greater than 4% by volume.
(3)
- 3. A. Zwolinski letter to 3. F. Opeka, " Reactor Operation with Deinerted Containment Drywell, Amendment No.102," dated June 5,1985.
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B12478/Page 3 June 1,1987 2.
Create the possibility of a new or different kind of accident from any previously analyzed. The change does not alter the 43-hour limit, and therefore has no potential for creating a new accident.
3.
Involve a significant reduction in a margin of safety, in that the change does not increase the probability of failure of the Millstone Unit No. I containment or the occurrence or consequences of any Design Basis Accident.
The Commission has provided guidance concerning the application of standards in 410CFR50.92 by providing certain examples (51FR 7751, March 6,1986). The changes proposed herein most closely resemble example (i), a purely administrative change to technical specifications; for example, a change to achieve consistency throughout the Technical Specifications, correction of an error, or a change in nomenclature. This change will clarify which activities are allowed inside containment during reactor operation, and will enhance operator understanding by using the phrase "necessary to ensure safe plant operation" rather than using "important to safety".
The Millstone Nuclear Review Board has reviewed and approved the attached proposed revisions and concurs with the above determinations.
In accordance with 10CFR50.91(b), we are providing the State of Connecticut with a copy of this proposed amendment.
Pursuant to the requirements of 10CFR170.12(c), enclosed with this amendment request is the application fee of $150.00.
Very truly yours, NORTHEAST NUCLEAR ENERGY COMPANY
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!W E. 3. yfo'czka
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Senior Vice President cc:
Mr. Kevin McCarthy Director, Radiation Control Unit Department of Environmental Protection Hartford, CT 06116 Mr. W. T. Russell, Region 1 Administrator Mr. 3. 3. Shea, NRC Project Manager, Millstone Unit No. I Mr. T. Rebelowski, Resident Inspector, Millstone Unit No. I
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B12478/Page' 4--
' June 1,-1987 STATE OF CONNECTICUT -)
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Then personally appeared before me E. 3. Mroczka, who being duly sworn, did state that he is Senior Vice President of Northeast Nuclear Energy Company, a Licensee herein, that he _ is authorized to execute and file the foregoing information in the name and on behalf of the Licensee herein and that the statements contained in said information are true and correct to the best of his knowledge and belief.
hAhwh Nbtary Publy My Commission EXP res March 31,1988 i