ML12075A001

United States Geological Survey - NRC Request for Additional Information Ar-41 Dose Calculations Relating to the License Renewal (Tac No. ME1593)

ML12075A001
Person / Time
Site:	U.S. Geological Survey
Issue date:	03/21/2012
From:	Geoffrey Wertz Research and Test Reactors Licensing Branch
To:	Adrian B US Dept of Interior, Geological Survey (USGS)
Wertz G
References
TAC ME1593
Download: ML12075A001 (5)

Text

March 21, 2012 Ms. Betty Adrian Reactor Administrator Department of the Interior U.S. Geological Survey PO Box 25046 MS 975 Denver Federal Center Denver, CO 80225-0046

SUBJECT:

U.S. GEOLOGICAL SURVEY - REQUEST FOR ADDITIONAL INFORMATION REGARDING THE LICENSE RENEWAL REVIEW FOR THE U.S.G.S TRIGA REACTOR (TAC NO. ME1593)

Dear Ms. Adrian:

The U.S. Nuclear Regulatory Commission (NRC) is continuing its review of your application for the renewal of Facility Operating License No. R-113 for the U.S. Geological Survey TRIGA Reactor (GSTR), dated January 5, 2009, (a redacted version of the safety analysis report is available on the NRCs public Web site at www.nrc.gov under Agencywide Documents Access and Management System (ADAMS) Accession No. ML092120136).

The NRC staff requires additional information and clarification on questions that have arisen during our review. Please provide responses to the enclosed request for additional information within 60 days of the date of this letter. In accordance with Title 10 of the Code of Federal Regulations (10 CFR), Section 50.30(b), you must execute your response in a signed original document under oath or affirmation. Your response must be submitted in accordance with 10 CFR 50.4, Written Communications. Information included in your response that is considered security, sensitive, or proprietary, that you seek to have withheld from the public, must be marked in accordance with 10 CFR 2.390, Public inspections, exemptions, requests for withholding.

If you have any questions about this review or if you need additional time to respond to this request; please contact me by telephone at 301-415-0893 or by electronic mail at geoffrey.wertz@nrc.gov.

Sincerely,

/LTran for RA/

Geoffrey Wertz, Project Manager Research and Test Reactors Licensing Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No. 50-274 cc: See next page

U.S. Geological Survey TRIGA Reactor Docket No. 50-274 cc:

Environmental Services Manager 480 S. Allison Pkwy.

Lakewood, CO 80226 State of Colorado Radiation Management Program HMWM-RM-B2 4300 Cherry Creek Drive South Denver, CO 80246 Mr. Timothy DeBey Reactor Director U.S. Geological Survey Box 25046 - Mail Stop 424 Denver Federal Center Denver, CO 80225 Test, Research, and Training Reactor Newsletter Universities of Florida 202 Nuclear Sciences Center Gainesville, FL 32611

ML12075A001 *concurrence via e-mail NRR-088 Office PRLB:PM* PRLB:LA PRLB:BC PRLB:PM Name GWertz GLappert JQuichocho GWertz Date 3/14/2012 3/15/2012 3/19/2012 3/21/2012

OFFICE OF NUCLEAR REACTOR REGULATION REQUEST FOR ADDITIONAL INFORMATION RE: RENEWAL OF THE FACILITY OPERATING LICENSE FOR THE UNITED STATES GEOLOGICAL SURVEY TRIGA REACTOR LICENSE NO. R-113; DOCKET NO. 50-274 The U.S. Nuclear Regulatory Commission (NRC) is continuing its review of your application for the renewal of Facility Operating License No. R-113 for the U.S. Geological Survey (USGS)

TRIGA reactor (GSTR), dated January 5, 2009. Our review conformed to the Interim Staff Guidance (ISG) on the Streamlined Review Process for License Renewal for Research Reactors (Agencywide Document Access and Management System Accession (ADAMS) No.

ML092240244). During this review, we have identified areas needing additional information.

Please note the RAI numbering follows sequentially from the RAIs provided in our letter dated September 29, 2010 (ADAMS Accession No. ML102510077).

Please address and provide responses to the following requests for additional information:

26. NUREG-1537, Part 1, Section 11.1.1.1, Airborne Radiation Sources, states that the licensee should estimate the release of airborne radionuclides to the environment and should use these releases to determine the consequences in the offsite environment.

Included in this analysis should be the does associated with the production and release of Argon-41. The USGS Safety Analysis Report (SAR), Section 11.1.1.1, Estimated Annual Dose in the Unrestricted Area form Ar-41 Released during Routine Reactor Operation, and Section 11.1.1.4, Routine Release of Ar-41 to Atmosphere, provide the results of the certain radiation dose estimates. However, there is insufficient detail in these SAR sections to allow the NRC staff to complete an evaluation. Please provide the following additional information:

a. USGS SAR, Section 11.1.1.1.1 states that the whole body dose from Ar-41 is a factor of 48.7 times less than the Title 10 of the Code of Federal Regulations (10 CFR) Part 20, Appendix B, values. Please provide the assumptions, calculations, and justification for the derivation of this factor.

b. USGS SAR, Section 11.1.1.1.1 states that an individual spending 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> per week with an Ar-41 air concentration of 4.35 x 10-6 micro-Curies per milliliter

(µCi/mL) would receive a radiation dose of about 66 milli-Roentgen Equivalent Man (mrem) per year. Please provide the assumptions, calculations, and justification for this dose estimate.

c. USGS SAR, Section 11.1.1.1.1 describes an accident involving flooding of the rotary specimen rack releasing Ar-41 into the reactor bay, with an estimated radiation dose of 17.9 mrem to an individual in the center of the reactor bay, and an estimated radiation dose of 208 mrem if the release involved 10 Ci of Ar-41.

Please provide the assumptions, calculations, and justification supporting these estimated radiation doses.

d. USGS SAR, Section 11.1.1.1.1 describes the routine exposure of personnel in unrestricted areas from Ar-41 releases assuming the person is standing next to the reactor building, at a distance of 8 meters from the release point. An annual release of 25 Ci of Ar-41 results in an whole body dose of less than 17 mrem per year a person near the building wall. Please provide the assumptions, calculations, and justification supporting the estimation of doses in the unrestricted area from annual operational releases of AR-41 to the atmosphere.

e. USGS SAR Section 11.1.1.1.4 discusses the estimation of offsite doses from routine releases of Ar-41. Please provide a reference and justification for the use of Equation 11.31 for estimating ground level concentrations of Ar-41 including the basis for the average air concentration during operations of 5.85 x 10-6 µCi per cubic meter. Please provide an evaluation of your analysis to meeting the regulatory limit cited in 10 CFR 20, Appendix B in units of µCi/mL, and an estimate of the dose to a member of the public.

27. NUREG-1537, Part 1, Section 11.2.3, Release of Radioactive Waste, requests that the licensee provide a description of all radioactive waste released to the environment, and a description of the controls in place to ensure that any liquid releases to the sanitary sewerage meet the requirements of 10 CFR 20.2003. USGS SAR Section 11.2.4 states that the licensees policy is not to normally release radioactive liquid waste. However, this statement does not prevent the potential release of radioactive liquid waste. Please provide a description of any potential radioactive liquid waste releases to the environment, and the controls in place to help ensure that any radioactive liquid releases meet the requirements of 10 CFR 20.2003.