ML20153E754

Expresses Disappointment in Quality & Approach of Staff SER, to Provide Comments on Some of Bases Considered in Issuance of Exemption to Allow Util to Discontinue Offsite Emergency Planning Activities.Factual Discrepancies Noted

ML20153E754
Person / Time
Site:	Maine Yankee
Issue date:	09/22/1998
From:	Zinke G Maine Yankee
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GAZ-98-49, MN-98-59, NUDOCS 9809280235
Download: ML20153E754 (6)

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4 MaineYankee P.O. BOX 408 + WISCASSET, MAINE 04578 + (207) 882-6321 e ,

September 22,1998 MN-98-59 GAZ-98-49 UNITED STATES NUCLEAR REGULATORY COMMISSION Attention: Document Control Desk Washington,DC 20555

References:

(a) License No. DPR-36 (Docket No. 50-309)

(b) Letter: M.J. Meisner to USNRC; Defueled Emergency Plan and 10 CFR 50.54(q) - Exemption Request (MN-97-119), dated November 6,1997 (c) Letter: M.J. Meisner to USNRC; Claim of Backfit " Generic Issue 82, Beyond Design Basis Accidents in Spent Fuel Pools"(MN-98-11), Dated February 17, 1998 (d) Letter: USNRC to M.J. Meisner; Exemption From Certain Requirements of 10 CFR 50.54(q),10 CFR 50.47(b) and (c), and Appendix E to 10 CFR Part 50 at Maine Yankee Atomic Power Station (TAC No. MA0069), dated September 3, 1998 '

(e) Letter: G.A. Zinke to USNRC; Summary of Maine Yankee's Bounding Radiological Analyses In Support of the Defueled Emergency Plan (MN-98-55),

dated /.ugust 5,1998 (f) Letter: M.J. Meisner to USNRC; Submittal of the Maine Yankee Defueled Safet- Analysis Report Rev.15 & 16 (MN-98 54), dated August 3,1998 (g) Luter G.A. Zinke to USNRC; Summary of Maine Yankee's Radiological Analyses Applicable to the Decommissioned Plant Condition (MN-98-050),

dated July 9,1998 (h) Letter: M.J. Meisner to USNRC; Request for Exemption From the Financial Protection Requirement Limits of 10CFR50.54(w) and 10CFR140.11 (MN 01), dated January 20,1998

Subject:

Emergency Plan Exemption Bases and Associated Information; Claim of Backfit

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Gentlemen:

In Reference (d), the Nuclear RegulMory Commission issued an exemption from certain requirements ,

of 10CFR50.54(q),10 CFR 50.47(b) and (c) and Appendix E to 10 CFR Part 50 for Maine Yankee in l

response to our application (Reference (b)) dated November 6,1997 as supplemented by other l

! correspondence. This exemption will allow Maine Yankee to discontinue offsite emergency planning )

activities and to reduce the scope ofonsite emergency planning. This was appropriate because the plant, in the permanently shutdown condition, poses a significantly reduced risk to the public health and safety.

l We appreciate the time and the effort that the NRC staff has expended in reviewing and approving this  !

exemption. This licensing action was made more difficult for both the staff and Maine Yankee because new requirements were being imposed without regard to due process.

9809280235 900922 I PDR ADOCK 05000309: l F PDR

u, MaineYankee

! UNITED STATES, NUCLEAR REGULATORY COMMISSION MN-98-59 i Attention: bocument Control Desk Page Two l The purpose of this letter is to express our disappointment in the quality and approach of the staff's SER, 1 to provide our comments on some of the bases which were considered in the issuance of the exemption l l and to point out some factual discrepancies. These comments and factual discrepancies are identified and

!~ explained in Attachments 1 and 2 to this letter. It is ourjudgement that neither these comments nor the factual discrepancies in any way invalidate the NRC's conclusion that the referenced exemptions are  ;

j acceptable.

- Two backfits are identified in Attachement I regarding the imposition of new constraints and boundary conditions associated with the Zire Fire scenario and the imposition of a complete SFP draindown scenario for the purpose cfcalculating the bounding radiological dose. In accordance with 10CFR50.109

, and USNRC Manual Chapter 0514 "NRC Program for Management of Plant-Specific Backfitting of Nuclear Power Plants," Maine Yankee requests that this claim of backfit be appropriately reviewed.

As described in the attachment, Maine Yankee does not accept into our license basis the imposition of the Zire Fire scenario, the new constraints and boundary conditions which the NRC has imposed upon it or the imposition of a complete SFP drain down scenario for the purpose of calculating the bounding

! radiological dose. The public would have been better served had exemption approval justification focused solely upon the inherently large safety margins associated with wet storage of spent fuel as they have done for other permanently shutdown plants. The public interest is served when concerns are raised which have a genuine relationship to the health and safety of the public. It is diluted when impossible scenarios are presented alongside other reasonable safety bases.

Finally, in discussions with the Director of NRR, it was our understanding that the emergency plan exemption SER and its associated bases would be consistent with the findings of the Backfit Review Panel. We believe the staff's SER does not reflect this understanding. Consequently, we request, upon publication of the Review Panel findings, that the emergency plan exemption SER be quickly revised to be consistent with the Panel findings.

Please contact us should you have any questions or desire additional information.

Very truly yours, George A. Zinke, Di or Nuclear Safety & Regulatory Affairs Attachments c: Mr. Ilubert Miller '

l Mr. Michael Webb

( Mr. Sam Collins l Mr. Leonard J. Callan  ;

Mr. John Zwolinski  ;

Mr. Dan Barss Mr. Patrick J. Dostie 1 Mr. Uldis Vanags I

Mr. John W. Libby, State Director, Maine Emergency Management Agency l i

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ATTACIIMENT 1 Invalid License Bases Imposed as Backfit 4 .

Comnlete Loss of SFP Water Inventory Maine Yankee disagrees with the consideration of the complete loss of spent fuel pool water inventor /

as a basis for determining that the emergency plan exemption is acceptable. This event has never been included in the licensing basis for Maine Yankee and is not part of the underlying purpose of the emergency planning rules. In Reference (c), Maine Yankee claimed backfit pursuant to 10CFR50.109 regarding the use of this scenario as the basis for approval of our emergency plan exemption. To base the approval of this exemption on this scenario is contrary to 10 CFR 50.109 and effectively disregards the associated due process of the rule. It effectively overrules the Backfit Review Panel's pending decision by presumptively adding this scenario to the Maine Yankee licensing basis. Maine Yankee does not accept the imposition of this scenario into our licensing basis.

In Re ference (c), Maine Yankee claimed backfit regarding the imposition ofnew requirements associated with the loss of spent fuel pool water inventory. This backfit claim and our subsequent appeal of the NRC determination has resulted in the establishment of a NRC Backfit Review Panel. A decision from this panel is pending.10CFR50.109(d) states: "No licensing action will be withheld during the pendency of backfit analyses required by the Commission's rules." The statements of consideration for the final Backfit rule (50FR38103) provides a comment on this aspect of the backfit rule. "During internal review of the rule, a question was raised as to whether licensing action should be withheld during backfit review.

The answer is that the rule never contemplated such a withholding. To the contrary, until a backfit analysis is complete, licensing action should continue along a course consistent with normal practice."

NRC Manual Chapter 0514 further amplifies this constraint: "If'immediate imposition' is not necessary, l

staff proposed backfits shall not be imposed, and plant construction, licensing action, or operation shall l not be interrupted or delayed by NRC actions, during the staff's evaluation and backfit transmittal process, or a subsequent appeal process, until final action is complete under this chapter." Indeed the NRC imposed on the license basis for Maine Yankee the subject of the Backfit claim and appeal, contrary to the intent of 10CFR50.109(d).

New Constraints and Boundary Conditions In addition, new constraints and boundary conditions have been imposed on the complete loss of spent fuel pool water inventory for Zire fire concerns. These new constraints and boundary conditions included the assumption of an adiabatic heatup of the hottest fuel assembly location in the highest power fuel assembly. An adiabatic heatup assumes a perfectly insulated system. While this assumption may be useful in thermodynamic theory, in reality it is impossible to achieve. This impossible assumption is added on to a beyond design basis scenario which has a very low probability of occurrence to produce a heatup calculation resulting in 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> to reach 900*C. This " bounding" scenario is later characterized as a " low likelihood" scenario. This is not a " low likelihood" scenario; it is an impossible and inconceivable scenario. The seemingly arbitrary imposition of these new constraints and boundary conditions demonstrates the importance of establishing new requirements and regulatory positions through the rigorous and disciplined backfit process prescribed in 10 CFR 50.109. These new constraints and boundary conditions, if accepted, would become part of the license basis, which would have to be maintained and preserved in ensuing accident analyses and change process activities. The addition of this impossible " perfectly insulated" assumption to a very low probability, beyond design basis scenario which results in a heatup calculation of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is not relevant and is unnecessarily alarming. Maine Yankee does not accept these new constraints and boundary conditions into its license basis and does not agree with the relevance of this impossible assumption and the resulting heatup time calculation. These new constraints and boundary conditions constitute backfits. Accordingly, Maine Yankee requests that this claim of backfit be appropriately reviewed in accordance with 10 CFR 50.109 and USNRC Manual Chapter 0514 "NRC Program for Management of Plant-Specific Backfitting of Nuclear Power Plants."

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ATTACIIMENT 1 Invalid License Bases Imposed as Backfit Radiolonical Dose Considerations Furthermore, the postulated offsite dose rates resulting from a complete draindown of the spent fuel pool are presented as a basis for approval of the exemption. While Maine Yankee did perform this calculation, Maine Yankee disagrees with the imposition of this scenario into the license basis for the Defueled Emergency Plan for the purpose of bounding the offsite dose rates. In Reference (e), Maine Yankee presented its bounding radiological dose scenario as a partial loss of water inventory from the spent fuel pool. This partial loss of water assumes a failure of the coolant return line siphon breaker which drains the pool to a level equivalent to approximately 10 feet of water covering the spent fuel in the storage cells. This inventory is allowed to boiloff without any operator action for four days resulting in a water level of approximately 5 feet above the spent fuel. Maine Yankee believes that this scenario should form the basis for the bounding radiological dose. Accordingly, Maine Yankee does not accept the imposition of the complete araindown scenario into the license basis for the bounding radiological dose. The imposition of the complete draindown for the purpose of calculating the bounding radiological dose constitutes a backfit. Accordingly, Maine Yankee requests that this claim of backfit be appropriately reviewed in accordance with 10 CFR 50.109 and USNRC Manual Chapter 0514 "NRC Program for Management of Plant-Specific Backfitting of Nuclear Power Plants."

Conclusion The approval of the exemption is justified based solely upon the inherently large safety margins associated with wet storage of spent fuel. The simplicity and robustness of the spent fuel pool design, as attested to by the NRC, includes seismic capability, six-foot thick reinforced-concrete walls and floor with a one-quarter inch steel liner founded upon bedrock and embedded below grade level to a elevation roughly equivalent to the top of the active fuel stored in the spent fuel racks. This design makes the partial or complete uncovery of fuel resulting from a loss of spent fuel pool water inventory of such low I probability that the scenario should have been eliminated from consideration on risk alone as has been done for other permanently shutdown plants, notwithstanding our claim of backfit.

In ourjudgement these comments on the bases do not in any way invalidate the NRC's conclusion that l the emergency plan exemption is acceptable. Since the NRC found the exemption acceptable after a l consideration of the Loss of Spent Fuel Pool Water Inventory scenario, asserting that this scenario did not need to be considered can not invalidate the acceptability of the exemption.

Fmally, in discussions with the Director of NRR, it was our understanding that the emergency plan exemption SER and its associated bases would be consistent with the findings of the Backfit Review Panel. We believe the staff's SER does not reflect this understanding. Consequently, we request, upon publication of the Review Panel findings, that the emergency plan exemption SER be quickly revised to l

be consistent with the Panel findings.

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ATTACIIMENT 2 i

SER I)iscrenancies 4 .

Maine Yankee would like to point out some specific factual discrepancies and/or comments in Reference (d).

1. On page 7 of the exemption, NRC identified the refueling water storage tank among the normal sources of makeup water for the spent fuel pool. This tank has now been declassified and abandoned in accordance with Maine Yankee procedures including a 10 CFR 50.59 determination. It appears ,

that the NRC drew its conclusion from an earlier version (Rev.14) of the Defueled Safety Analysis 1 Report. Maine Yankee would like to refer the NRC to the latest revision of the DSAR submitted to the NRC pursuant to 10 CFR 50.71(e) on August 3,1998, by Reference (f). In ourjudgement, this factual discrepancy does not m any way invalidate the NRC's conclusion that the emergency plan exemption is acceptable since there are several other sources of makeup water to the spent fuel pool.

2. On page 4 of the exemption, the NRC states: "The licensee also estimates that, by March 1998, a beyond-design-basis event, involving fuel damage (caused by a loss of spent fuel pool water and a subsequent overheating of the stored fuel) and the release ofradioactive materials sufficient to exceed 1 EPA PAGs at the site boundary is not credible." The March 1998 estimate, which we provided in  !

Reference (b) before the calculation was completed, was later found to be conservative. I Notwithstanding our earlier assertion that this scenario need not be considered, in fact, our I calculation concluded that this scenario would be incredible by January 16,1998, not March 1998, as noted in Reference (h).

3. On page 4 of the exemption, the NRC states: " Chapter 5 of the DSAR describes the radiological consequences of accidents that could release radioactive materials and the consequences of a spent

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fuel pool draindown event." This statement is misleading in that it infers that the DS AR considered i and describes the spent fuel pool draindown event, meaning a complete draindown. For the record, Maine Yankee would like to point out that the Chapter 5 of the DSAR has never included the complete draindown of the spent fuel pool. Chapter 5 does describe a loss of spent fuel pool  !

inventory event that decreases the water level of the spent fuel pool to various water level depths I above the active fuel, but never below it. This event was considered to show the excessive amount of time available to the operators to detect the loss (without taking credit for installed instrumentation) and initiate corrective actions. Due to the simplicity and robustness of the spent fuel pool design, there is no credible or reasonably conceivable mechanism, within the bounds of relative risk, to result in an undetected or catastrophic loss of complete spent fuel pool water inventory.

Therefore, this event was not only deselected from DSAR design basis events, but was deemed l inappropriate for consideration as a beyond-design-basis event for other license basis requirements l such as emergency planning and nuclear insurance. l

4. On page 5 of the exemption, the NRC states: " resin liner filling and dewatering operations are performed in containment." This statement should not be taken out of context. In Reference (g),

Maine Yankee described the Reactor Coolant System Decontamination (RCS Decon) evolution. It was in this context that Maine Yankee stated that "all work was performed inside the closed containment building." This is not to suggest that all resin liner filling and dewatering operations will be performed in containment; only those which were associated with the RCS Decon. liowever Maine Yankee continues to maintain the DSAR commitment to establish administrative controls to ensure that calculated offsite doses from potential decommissioning accidents do not exceed those calculated for a spent resin cask drop accident, as described in DSAR sections 5.6.3 and 7.3.1.

Therefore, in ourjudgement, the conclusions of the emergency plan exemption approval (Reference (d)) are not affected.

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ATTACHMENT 2 SER Discrenancies

5. On page 2 of the exemption, the NRC states: "The licensee stated that the remaining requirements  ;

of 10 CFR 50.54(q),10 CFR 50.47(b) and (c), and Appendix E to Part 50 will be addressed in the DEP." Maine Yankee has no record of making such a statement. However, it is Maine Yankee's

. intention to ensure that the remaining applicable requirements are complied with and, as appropriate, addressed in the DEP. This is not to say that all the remaining requirements of the CFR sections specified above need to be addressed in the DEP itself, I

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