ML18064A623
| ML18064A623 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 02/10/1995 |
| From: | Haas K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML18064A624 | List: |
| References | |
| NUDOCS 9502240216 | |
| Download: ML18064A623 (4) | |
Text
consumers Power POWERING MICHlliAN"S PROGRESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert, Ml 49043 February 10, 1995 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT KurtM. Haas Plant Safety and Licensing Director PRESSURE-TEMPERATURE LIMITS TECHNICAL SPECIFICATIONS CHANGE REQUEST - ANSWERS TO REVIEWERS QUESTIONS On October 5, 1995, Consumers Power Company submitted a Technical Specifications change request (TSCR) proposing revised Primary Coolant System Pressure-Temperature limits.
During review of that request, the NRR reviewer, Mr. Chu Liang, raised two questions related to analytical assumptions regarding the presence of a steam space, or 11 bubble", in the pressurizer.
Question 1):
Does Consumers Power Company have analyses to show that the Pressurizer bubble referenced in proposed Specification 3.l.lh(4) provides sufficient protection to allow starting a PCP with the S/G secondary temperature l00°F above the PCS cold leg temperature?
Answer 1):
Yes.
A PCP start with the stated l00°F temperature difference was analyzed and found to be satisfactory. That analysis assumed that the pressurizer was 11 solid 11
, so no credit was taken for the pressurizer bubble in assuring that PCS pressure would remain below.the Appendix G limits presented in proposed Figures 3-1 and 3-2. This analysis is discussed in Attachment 3 to the October 5, 1994 TSCR under section 4.2.4.2 11 PCP Starts 11 The requirement to have a pressurizer bubble is only intended to provide additional margin by significantly reducing the pressure transient for such a PCP start.
Existing Specification 3.1.lh provides the same allowance for PCP.
starts with the l00°F temperature difference, except for temperatures between 170 and 210°F.
The calculated effects of PCP starting in this temperature range were reviewed and found to be acceptable with the stipulated l00°F temperature difference.
A CMS' ENERGY COMPANY
I Quesiion 2):
Does Consumers Power Company have analyses to support the operation of P-50A and P-508 together, below 300°F, when Pressurizer level is below 57% (proposed specification 3.1.li) as discussed in the second paragraph of the 11 PCP Starting Limits" discussion on the first page of the TSCR?
Answer 2):
No.
A review of the proposed specification 3.1.li and its relation to the pressure limits of Figures 3-1 and 3-2 indicate that the reference to pressurizer level in 3.1.li is inappropriate.
The TSCR paragraph in question is:
"A new limit on operating PCPs P-50A and P-508 together has been added to provide additional acceptable area below the Pressure Temperature limit curves.
The limitation on operating P-50A and P-508 together with T0 below 300°F and pressurizer level above 57% allows the Pressure Temperature limits to be 19 psi higher than they would be without this limit.
The 57%
pressurizer level is not an analytical result, but simply a decision point between having and not having a bubble.
It was chosen to agree with the maximum programmed level during power operation."
The associated specification (3.1.li) is:
"When the PCS cold leg temperature is < 300°F and pressurizer level is > 57% the primary coolant pumps P-50A and P-508 shall not be operated simultaneously."
Proposed limitation 3.l.lh(4) is intended to allow a slightly higher indicated Primary Coolant System (PCS) pressure during operation below 300°F than would be allowed without such a limit. This allowance was used in calculation of the pressure limits in proposed Figures 3-1 and 3-2.
The pressurizer, where the PCS pressure is measured, is connected to the PCS on the hot leg which is effectively a common suction line for P-50A and P~508. If PCPs P-50A and P-508 are operated together the indicated pressure would be lower, with respect to the pressure at the limiting reactor vessel weld, than with one pump or other pairs of pumps operating.
The reference to pressurizer level in proposed specification 3.1.li was intended to provide additional margin, as it does in proposed specification 3.l.lh(4), discussed above.
When considering Mr.
Liang's questions, it was realized that proposed specification 3.1.li is a steady state consideration, when the presence of a pressurizer bubble would have no significant effect. A revised page 3-ld has been attached, removing the reference, in 3.1.li, to pressurizer level and clarifying the basis.
The change to specification 3.1.li proposed in this letter does not affect the concl.usions of the No Significant Hazards analysis in our October 5, 1994 letter on this subject.
SUMMARY
OF COMMITMENTS This letter contains no new commitments or revisions to former commitments.
/~
Kurt M. Haas Director, Plant Safety & Licensing CC Administrator, Region III, USNRC Resident Inspector, Palisades State of Michigan Attachment
CONSUMERS-POWER COMPANY To the best of my knowledge, the contents of this Technical Specifications change request, deferring several 18 month interval surveillance requirements until the upcoming refueling outage, are truthful and complete.
By --:::....:....,~L..:......,~,_L---:-f____:_:~.,.---------,-,--,------:-~--:~
D President Electric Sworn and.subs c r i bed to before me this fOjf., day of ~
_ 1995.
/nOJvlcc 0. '3-aJL Marla A. Fall, Notary Public Jackson County, Michigan My commission expires July 20, 1999
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