ML23053A050

From kanterella
Jump to navigation Jump to search
Cover Memo and Response to C-10 Questions Regarding 3Q2022 Inspection Report
ML23053A050
Person / Time
Site: Seabrook NextEra Energy icon.png
Issue date: 02/22/2023
From: Matt Young
NRC/RGN-I/DORS
To: Skibbee P
C-10 Research & Education Foundation
References
Download: ML23053A050 (1)


Text

February 22, 2023 Patricia L. Skibbee Board President C-10 Research and Education Foundation 11 Chestnut Street Amesbury, MA 01913

Dear Patricia Skibbee:

I am responding to your email from December 16, 2022, on the Seabrook Integrated Inspection Report (ADAMS Accession No. ML22326A180). Responses to the specific questions are enclosed.

Sincerely, Matt R. Young, Chief Projects Branch 2 Division of Operating Reactor Safety

Enclosure:

As stated Matthew R.

Young Digitally signed by Matthew R.

Young Date: 2023.02.22 09:39:58

-05'00'

ML23053A050 x

SUNSI Review x

Non-Sensitive Sensitive x

Publicly Available Non-Publicly Available OFFICE RI/DORS RI/ORA RI/DORS RI/DORS RI/DORS RI/DORS NAME JDeBoer DScrenci TDaun SElkhiamy NFloyd MYoung DATE 2/14/23 2/14/23 2/14/23 2/14/23 2/16/23 2/14/23

Enclosure U.S. Nuclear Regulatory Commission Response to Questions in the December 16, 2022, memorandum, and email As you requested, we are responding to the questions listed below.

Q1. First, the green NCV on the failure of the staff to properly implement the required hourly walk-downs of the A safety injection pump room during the time the fire alarms were not all functioning at that location. As you are aware, this is the same violation that occurred and was documented in the 2021 4th quarter IIR, different location. At that time, further training and therefore future proper implementation was ensured. Why did this same failure occur again? At what point do such repeated violations, if any, escalate to cited violations?

The failure to implement appropriate compensatory hourly fire patrol occurred because the licensee failed to properly use a formal process to evaluate an alternate compensatory action to ensure all aspects of an adequate fire watch were being performed. Specifically, the plant staff were doing fire rounds in the vicinity, a zone two levels above the room that required fire patrol and did not evaluate the appropriateness of the action. The inspectors identified that the alternate compensatory action taken by the licensee did not provide the ability to see the entire area requiring surveillance and affected the ability to identify a potential fire. Section 2.3.2 of the NRC Enforcement Policy specifies when repeated violations are escalated to cited violations. This was not to a cited violation because green violations are not escalated.

Q2. The service water cooling tower inspection results on August 23 revealed this structure is nearing its threshold limits due to ASR expansion. (AR 02434877). (report section 71111.15)

This situation is particularly troubling due to factors specifically pertaining to the service water cooling tower structure. Such towers have a relative humidity of nearly 100%, while the temperatures can be around 40-50 degrees Celsius, providing an environment ideal for ASR progression. ASR in this structure has not, to our knowledge, been mentioned in earlier reports.

This situation generates questions:

1-Where was the ASR detected (inside or outside)? (detection on the outside is of greater concern, since the humidity and temperature are both higher on the inside.)

2-What were the observed values/crack indices?

3-Have samples been extracted for laboratory confirmation?

4-If so, how representative is the apparently single measurement taken of the entire structure?

5-What is the future (immediate future) plan for further inspection to determine other ASR locations where this could be occurring but not observed using the currently required observation measures in this structure?

Visual indications of the effects of ASR were observed on specific locations inside and on the exterior of the structure. Core samples have been taken from this structure as well as many other safety-related structures in accordance with Seabrooks structures monitoring program. The NRC previously reviewed the service water cooling tower when it exceeded a threshold limit and documented the results of our review in Inspection Report 05000443/2021002 (ML21222A126). In general, the structure meets the code requirements with the addition of ASR loads except for a few structural elements. The inspectors reviewed the licensees prompt operability determination and supporting structural evaluations and calculations to verify that NextEra staff appropriately justified the functional capability for this structure.

The inspectors concluded that the structural evaluation was completed in accordance with the NRC-approved methodology document and the structure remained capable of performing its intended safety

2 function. This structure was reviewed again in the NRCs November 22, 2022, inspection report when a threshold limit was identified to be nearing its limit. NextEra plans to continue to monitor this structure at an increased frequency under the structures monitoring program to ensure it stays within the analyzed limits or until a structural modification is completed.

Q3. What specific actions have been instituted/contemplated by NextEra (and/or required by the NRC) in response to the finding that the service water cooling tower is nearing its threshold limit?

NextEra intends to conduct structural modifications to the service water cooling tower that will increase the available margin to ASR building deformation-related limits as well as several compensatory actions in the interim, including monitoring at increased frequency. In accordance with the licensees NRC-approved methodology document and the structures monitoring program, a structural re-evaluation is required once a threshold limit is exceeded which may result in refined threshold limits or the need for corrective action such as physical structural modification.

Q4. What is the historical time frame from a finding in the POD procedure to a real repair/fix?

The word promptly is used in the regulations, but what is the actual timeline?

The time frame for implementing a repair is dependent on several factors and is governed by the safety significance of the structure, system, or component. The licensee is required is to ensure the structure, system, or component will be capable of performing its specified safety functions when needed, until the next surveillance test or scheduled inspection measurement, and or until the corrective action (repair) is completed.

Q5. Generally and overall, with the numerous issues now in play at the plant-including ASR-it seems that a quarterly report would contain many more findings. Why is this report so brief?

The report documents the inspections that were completed in the quarter in accordance with NRC Inspection Manual Chapter 0611, Power Reactor Inspection Reports, and NRC Inspection Manual Chapter 0612, Issue Screening. The inspection report accurately documents any more than minor performance deficiencies identified by NRC inspectors.