L-MT-22-004, Technical Specification 5.6.4 Post Accident Monitoring Report

Technical Specification 5.6.4 Post Accident Monitoring Report

ML22020A168
Person / Time
Site:	Monticello
Issue date:	01/20/2022
From:	Conboy T Northern States Power Company, Minnesota, Xcel Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-MT-22-004
Download: ML22020A168 (3)

Text

(l Xcel En ergy

• 2807 West County Ro ad 75 Monticello, MN 55362

January 20, 2022 L-MT-22-004 Technical Specification 5.6.4

ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Monticello Nuclear Generating Plant Docket No. 50-263 Renewed Facility Operating License No. DPR-22

Subject:

Technical Specification 5.6.4 Post Accident Monitoring Report

Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter "NSPM"), hereby submits a special report per Technical Specification 5.6.4, Post Accident Monitoring (PAM) Report. The special report provides notification that the inoperable Division 1 Suppression Pool Temperature Monitoring System (SPOTMOS) was not restored within the Technical Specification completion time.

If you have any questions about this submittal, please contact Gustavo Hernandez, Site Regulatory Affairs Manager, at 763-271-6746.

Summary of Commitments

This letter makes no new commitments and no revisions to existing commitments.

Thomas A. Conboy Site Vice President, Monticello ucle r Generating Plant Northern States Power Company - Minnesota

Enclosure

cc: Administrator, Region Ill, USNRC Project Manager, Monticello, USNRC Resident Inspector, Monticello, USNRC State of Minnesota ENCLOSURE

MONTICELLO NUCLEAR GENERATING PLANT TECHNICAL SPECIFICATION 5.6.4 POST ACCIDENT MONITORING REPORT

On 12/09/2021 at 2308, Operations declared Tl-4072A, Division 1 Torus Temperature Indicator, INOPERABLE. Operators were performing routine Control Room board monitoring and discovered that Tl-4072A had a blank display. Operators attempted to wake up the indicator on the recorder, but the display remained blank. Tl-4072A is the remote indication for Division 1 of Suppression Pool Temperature Monitoring Systems (SPOTMOS). Suppression pool water temperature is a Type A and Category 1 variable provided to detect a condition that could potentially lead to containment breach and to verify the effectiveness of Emergency Core Cooling System (ECCS) actions taken to prevent containment breach. The suppression pool water temperature instrumentation allows operators to detect trends in suppression pool water temperature. The suppression pool water temperature is monitored by two redundant channels. Each channel consists of eight resistance temperature detectors (RTDs) that monitor temperature over a range of 30°F to 230°F. This issue was entered into the Corrective Action Program (QIM 501000058938).

Technical Specification (TS) 3.3.3.1, Table 3.3.3-1, Function 7, Post Accident Monitoring (PAM) Instrumentation, requires 2 Channels of suppression pool water temperature instrumentation to be Operable. The Required Action for 3.3.3.1 Condition A for one required Channel inoperable is to restore the required Channel to OPERABLE within 30 days. If the Channel is not restored within 30 days, a report in accordance with TS 5.6.4, Post Accident Monitoring Report, is required within the following 14 days.

TS 5.6.4 states that a report shall be submitted within the following 14 days. The report shall outline the preplanned alternate method of monitoring, the cause of the inoperability, and the plans and schedule for restoring the instrumentation channels of the Function to OPERABLE status.

Due to parts availability, the INOPERABLE Channel could not be restored within the 30-day LCO action date of 1/8/2022. Therefore, in accordance with TS 5.6.4, a PAM Report is required. Subsequently, on 1/13/2022, the display for Tl-4072A was replaced and the Channel was restored to OPERABLE status.

PRE-PLANNED METHOD OF MONITORING

During the time Tl-4072A was INOPERABLE, there were multiple means of alternate Torus water temperature monitoring available to support plant operations. While the Division 1 temperature indicator in the Control Room was providing the operators a blank screen, the same Division 1 indication remained available in the Control Room through the plant process computer system. Additionally, alternate Division 1 indication remained available to operators in the cable spreading room via TR-4072A, Division 1 Torus Temperature Printer. An annunciator common to both divisions of SPOTMOS is also available in the Control Room with

Page 1 of 2 alarm setpoints of 90°F, 105°F, 110°F, 120°F. There are also non-divisional Torus Water Temperature indications available in the Control Room, panel C-21, TR-23-115 points 18 & 19.

Finally, the independent Torus Water Temperature indication functions are available on Division 2 from Tl-4072B, in the Control Room, TR-4072B in the 3rd floor Emergency Filtration Train room, and the associated Division 2 SPOTMOS computer point via the plant process computer system.

CAUSE OF INOPERABIL TY

The cause of INOPERABILITY was due to a failed display on Tl-4072A.

PLANS/SCHEDULE FOR RESTORATION

The required parts were received on 1/10/2022. On 1/13/2022, the display for Tl-4072A was replaced and the Channel was restored to OPERABLE status.

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