ML110950059

Response to Questions 23.1, 23.2, and 23.3 of the Referenced RAI

ML110950059
Person / Time
Site:	U.S. Geological Survey
Issue date:	03/28/2011
From:	Timothy Debey US Dept of Interior, Geological Survey (USGS)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML110950059 (3)

Text

ZUSGS science for a changingworld Department of the Interior US Geological Survey PO Box 25046 MS 974 Denver, CO 80225-0046 March 28, 2011 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555

Reference:

U.S. Geological Survey TRIGA Reactor (GSTR), Docket 5 0-274, License R-113 Request for Additional Information (RAI) dated September 29, 2010

Subject:

Response to Questions 23.1, 23.2, and 23.3 of the Referenced RAI Mr. Wertz:

Our responses to Questions 23.1, 23.2, and 23.3 are provided on the following pages.

Sincerely, Tim DeBey U.S. Geological Survey Reactor Supervisor I declare under penalty of perjury that the foregoing is true and correct.

Executed on 3/28/11 Copy to:

Betty Adrian, Reactor Administrator Denver Federal Center MS 975 Dog

USGS Response to October, 2010 RAI Questions 23.1, 23.2, and 23.3.

Question 23

23. ANSI/ANS-15.1-2007, Section 4, "Surveillance Requirements," identifies Surveillance Requirements (SRs) for LCOs. The following GSTR SR items were identified. Please explain:

23.1 SR 14.4.1 Reactor Core Parameters, Specification 2, does not include any criteria for determining what represents a "significant change" in core configuration.

23.2 There does not appear to be a SR for ensuring the proper installation of the mechanical stop for the transient control rod per LCO 14.3.1.2.

23.3 There does not appear to be a SR for assuring that aluminum-clad fuel is loaded only in the F and G rings of the core per LCO 14.3.1.3.

23.4 There does not appear to be a SR for assuring that steady state power limit of 0.1 MW is not exceeded per LCO 14.3.1.3.

23.1 The phrase "as determined by the Reactor Administrator, Reactor Supervisor or Senior Reactor-in-Charge" to the end of GSTR TS 14.4.1 "Reactor Core Parameters" Specifications 2, 3 and 4. These will now read:

2. The total reactivity worth of each control rod shall be measured following any significant change in core or control rod configurationas determined by the ReactorAdministrator,Reactor Supervisor or Senior Reactor-in-Charge.

3. The shutdown reactivity shall be determinedprior to each day's operation,prior to each operationextending more than one day, or following any significantchange in core or control rod configuration as determined by the ReactorAdministrator,Reactor Supervisoror Senior Reactor-in-Charge.

4. The core excess reactivity shall be determined priorto each day's operation or following any significantchange in core or control rod configurationas determined by the Reactor Administrator,Reactor Supervisoror Senior Reactor-in-Charge.

23.2 An additional Specification will be added to GSTR TS 14.4.2 "Reactor Control and Safety Systems" to read as follows:

6. The proper installationof the mechanicalstopfor the transientcontrol rod shall be verified by visual inspection monthly.

The current GSTR TS 14.4.1 "Reactor Core Parameters" Specification 6 ("These checks are not required if the reactor core has been defueled.") will be renumbered as Specification 7.

23.3 An additional Specification will be added to GSTR TS 14.4.1 "Reactor Core Parameters" to read as follows:

8. The loading of aluminum-cladfuel only in the F and G rings of the core shall be verified by visual inspection priorto each day's operation.

The current GSTR TS 14.4.1 "Reactor Core Parameters" Specification 7 ("These checks are not required if the reactor core has been defueled.") will be renumbered as Specification 8.

23.4 This question will be answered with question 21 at a later date.