05000247/LER-2014-001, Regarding Technical Specification (TS) Prohibited Condition Due to Failure to Comply with TS 3.4.3 Reactor Coolant System Pressure-Temperature Limits During Vacuum Refill
| ML14107A343 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  (DPR-026, DPR-064) |
| Issue date: | 04/07/2014 |
| From: | Ventosa J Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-14-037 LER 14-001-00 | |
| Download: ML14107A343 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(ii) |
| 2472014001R00 - NRC Website | |
text
Entergy Indian Point Energy Center 450 Broadway, GSB P.O. Box 249 Buchanan, N.Y. 10511-0249 Tel (914) 254-6700 John A. Ventosa Site Vice President Administration NL-14-037 April 7, 2014 U.S. Nuclear Regulatory Commission Document Control Desk 11545 Rockville Pike, TWFN-2 F1 Rockville, MD 20852-2738
SUBJECT:
Licensee Event Report # 2014-001-00, "Technical Specification (TS)
Prohibited Condition Due to Failure to Comply with TS 3.4.3 Reactor Coolant System Pressure-Temperature Limits During Vacuum Refill" Indian Point Unit Nos. 2 and 3 Docket No. 50-247, 50-286 DPR-26, 64
Dear Sir or Madam:
Pursuant to 10 CFR 50.73(a)(1), Entergy Nuclear Operations Inc. (ENO) hereby provides Licensee Event Report (LER) 2014-001-00. The attached LER identifies an event where there was a Technical Specification (TS) Prohibited Condition due to violation of the reactor coolant system pressure-temperature limits during vacuum refill, which is reportable under 10 CFR 50.73(a)(2)(i)(B). This condition was recorded in the Entergy Corrective Action Program as Condition Report CR-IP2-2014-00877.
There are no new commitments identified in this letter. Should you have any questions regarding this submittal, please contact Mr. Robert Walpole, Manager, Regulatory Assurance at (914) 254-6710.
Sincerely, JAV/cbr cc:
Mr. William Dean, Regional Administrator, NRC Region I NRC Resident Inspector's Office, IPEC Ms. Bridget Frymire, New York State Public Service Commission
Abstract
On February 20, 2014, Entergy identified a failure to comply with Technical Specification (TS) 3.4.3 [Reactor Coolant System (RCS) Pressure and Temperature (P/T) Limits] after review of a Westinghouse PWR Owners Group (PWROG) correspondence (OG-14-66) dated February 19, 2014.
The PWROG correspondence discussed a Non-cited Violation at Perry Nuclear Plant for failure to comply with their TS for RCS P/T limits when operating the plant with a vacuum in the reactor pressure vessel (RPV) during cold startups and cooldowns.
A review of the Indian Point Units 2 and 3 TS 3.4.3 determined that TS 3.4.3 P/T limits for heatup and cooldown only provide for values greater than or equal to 0 psig.
TS 3.4.3 requires that the RCS pressures and temperatures be maintained within limits at all times specified in TS Figures 3.4.3-1 and 3.4.3-2.
The P/T Figures provide curves with a pressure starting at 0 psig.
During past operation at both units, TS 3.4.3 P/T limits were not complied with when performing vacuum refill in Mode 5 as this process results in RCS pressures less than 0 psig.
Cause of the event was a failure to recognize that a negative pressure was not allowed by the TS.
Corrective actions for Unit 2 was a TS amendment that was processed and approved by the NRC to include the acceptability of the vacuum refill condition.
Corrective actions for Unit 3 will be to submit a change to the TS to support this condition.
The event had no effect on public health and safety.
(If more space is required, use additional copies of (if more space is required, use additional copies of NRC Form 366A) (17)
The Indian point Unit 2 and Unit 3 TS 3.4.3, Figures 3.4.3-1 and Figure 3.4.3-2 heatup and cooldown limits only contain values for RCS pressures equal to or greater than 0.0 psig.
TS 3.4.3 requires that RCS pressures and temperatures be maintained within the limits specified in the TS at all times.
During startup from previous refueling outages, the RCS was made water solid, and during filling of the RCS, a vacuum was drawn so as to expel any air/non-condensibles from the RCS.
During this evolution, the RCS was below 0.0 psig, which is outside the range of the TS 3.4.3 figures.
The TS 3.4.3 requirements were not complied with during vacuum fill of the RCS and is therefore a TS prohibited condition.
The condition is not reportable in accordance with 10CFR50.73(a) (2) (ii), Any event or condition that resulted in (A) The condition of the power plant, including its principal safety barriers, being seriously degraded; or (B) the nuclear power plant being in an unanalyzed condition that significantly degraded plant safety.
The heatup, cooldown limitation curves remain valid during vacuum fill in accordance with current regulations.
These limitation curves were established in compliance with the methodology used to calculate and predict effects of radiation embrittlement of the Reactor Pressure Vessel beltline materials and remain valid during vacuum fill.
Since operation was within the limitation curves, the RCS materials behaved in a non-brittle manner consistent with the original design basis.
Therefore, there was no principal safety barriers seriously degraded nor was there any condition that significantly degraded plant safety.
Past Similar Events A review was performed of the past three years for Licensee Event Reports (LERs) reporting a TS prohibited condition due to a non-compliant TS.
No LERs were identified.
Safety Significance
This event had no effect on the health and safety of the public.
The RCS pressure boundary is a barrier against the release of radioactivity generated within the reactor and is designed to ensure a high degree of integrity throughout the life of the plant.
The RCS pressure boundary is capable of accommodating the temperatures and pressures associated with operational transients.
The RCS components containing the reactor coolant (i.e., reactor vessel, reactor coolant pumps, pressurizer, steam generator tubes, and RCS piping) are designed with sufficient wall thickness to withstand full system pressure.
The minimum wall thickness for the RCS components to withstand full vacuum (0 psia) is below the existing wall thickness of the reactor vessel, pressurizer, steam generator tubes, and the RCS piping.
Performance of RCS vacuum fill and vent process to reduce RCS pressure up to and including full vacuum will not adversely affect the integrity of RCS components.
The NRC review of the proposed changes to the TS P/T figures that included reference to vacuum fill of the RCS performed in Mode 5 under sub-atmospheric pressure and isothermal condition, verified that the proposed P/T limits are in accordance with Appendix G to Section XI of the ASME code and satisfy the requirements of Appendix G to 10CFR50.
Therefore, RCS vacuum fill and vent is not considered to be safety significant.