ML22166A324

Hermes CP Doc - Follow-up Questions on the Inert Gas System for the General Audit

ML22166A324
Person / Time
Site:	Hermes File:Kairos Power icon.png
Issue date:	06/09/2022
From:	NRC
To:	NRC/NRR/DANU
References
Download: ML22166A324 (4)

Text

From:

Beasley, Benjamin Sent:

Thursday, June 9, 2022 3:38 PM To:

Drew Peebles; Jim Tomkins Cc:

Darrell Gardner; Martin Bryan; Chereskin, Alexander; Helvenston, Edward; Cuadrado de Jesus, Samuel

Subject:

Follow-up questions on the Inert Gas System for the General Audit Drew and Jim, Below are questions on the Inert Gas System for the General Audit. These questions are following up on the prior audit discussion of the Inert Gas System and documents shown to us during the audit. I will schedule a meeting in about a week to discuss these questions.

Regards, Ben

~~~~~~~~~~~

Benjamin Beasley Senior Project Manager Advanced Reactor Licensing Branch 1 Office of Nuclear Reactor Regulation 301-415-2062 Benjamin.Beasley@nrc.gov 9.1-14 HER-EP-RQT-520-0000-REVA states that the IGS shall be able to vent cover gas to maintain core cooling. Clarify how venting of the cover gas maintains core cooling and if it is needed to maintain core cooling during a transient or postulated accident. Additionally, is the IGS needed to meet any of the PDC associated with this function?

9.1-15 Section 4.1.2 of HER-EP-RQT-520-0000-REVA states the cover gas leak rate shall comply with acceptable contaminant levels allowed and leakage could spread radioactive materials and increase the site boundary dose.

Clarify whether the IGS boundary is credited to meet PDCs 16 and/or 60.

9.1-16 Section 4.1.1 of HER-EP-RQT-520-0000-REVA states the IGS uses gas pressure as the motive force for transfer of salt to/from the tanks to/from the vessel. If there is a malfunction in the pressure control part of the IGS, are there ways to prevent flow in the wrong direction (e.g. due to a sudden pressure drop)?

9.1-17 During the previous audit discussion, Kairos noted that the IGS was analyzed for an overpressure event. Was the IGS analyzed to determine whether a high initial pressure during a postulated event can hinder natural circulation of the salt coolant?

9.1-18 HER-EP-RPT-000-0005-RevB assumes a PHSS hot cell temperature for the PHSS malfunction. Will the IGS have a TS to ensure the PHSS is maintained at the appropriate temperatures assumed for the transient analyses?

Additionally, does the IGS need to maintain conditions (e.g. pressure, temperature) to support initial condition assumptions for any other transient analyzed?

Hearing Identifier:

KairosPower_CPDocs_Public Email Number:

23 Mail Envelope Properties (BY3PR09MB73613FF61708E9283581B2D096A79)

Subject:

Follow-up questions on the Inert Gas System for the General Audit Sent Date:

6/9/2022 3:37:36 PM Received Date:

6/9/2022 3:37:00 PM From:

Beasley, Benjamin Created By:

Benjamin.Beasley@nrc.gov Recipients:

"Darrell Gardner" <gardner@kairospower.com>

Tracking Status: None "Martin Bryan" <bryan@kairospower.com>

Tracking Status: None "Chereskin, Alexander" <Alexander.Chereskin@nrc.gov>

Tracking Status: None "Helvenston, Edward" <Edward.Helvenston@nrc.gov>

Tracking Status: None "Cuadrado de Jesus, Samuel" <Samuel.CuadradoDeJesus@nrc.gov>

Tracking Status: None "Drew Peebles" <peebles@kairospower.com>

Tracking Status: None "Jim Tomkins" <Tomkins@kairospower.com>

Tracking Status: None Post Office:

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