ML070320408
| ML070320408 | |
| Person / Time | |
|---|---|
| Site: | 05000139 |
| Issue date: | 02/07/2007 |
| From: | Alexander Adams NRC/NRR/ADRA/DPR/PRTA |
| To: | Addison S Univ of Washington |
| Adams A, NRC/N RR/DRIP/REXB, 415-1127 | |
| References | |
| TAC MD2586 | |
| Download: ML070320408 (4) | |
Text
February 7, 2007 Dr. Stanley Addison, Radiation Safety Officer Environmental Health and Safety University of Washington 223 Hall Health Center Mail Stop 354400 Seattle, Washington 98195-4400
SUBJECT:
UNIVERSITY OF WASHINGTONREQUEST FOR ADDITIONAL INFORMATION RE: LICENSE TERMINATION (TAC NO. MD2586)
Dear Dr. Addison:
We are continuing our review of your request for termination of Facility License No. R-73 for the University of Washington Research Reactor which you submitted on December 13, 2006.
During our review of your Final Status Survey Report, questions have arisen for which we require additional information and clarification. Please provide responses to the enclosed request for additional information within 30 days of the date of this letter. In accordance with 10 CFR 50.30(b), your response must be executed in a signed original under oath or affirmation. Following receipt of the additional information, we will continue our evaluation of your request.
If you have any questions regarding this review, please contact me at (301) 415-1127.
Sincerely,
/RA/
Alexander Adams, Jr., Senior Project Manager Research and Test Reactors Branch A Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No. 50-139 License No. R-73
Enclosure:
As stated cc w/enclosure: See next page
February 7, 2007 Dr. Stanley Addison, Radiation Safety Officer Environmental Health and Safety University of Washington 223 Hall Health Center Mail Stop 354400 Seattle, Washington 98195-4400
SUBJECT:
UNIVERSITY OF WASHINGTONREQUEST FOR ADDITIONAL INFORMATION RE: LICENSE TERMINATION (TAC NO. MD2586)
Dear Dr. Addison:
We are continuing our review of your request for termination of Facility License No. R-73 for the University of Washington Research Reactor which you submitted on December 13, 2006.
During our review of your Final Status Survey Report, questions have arisen for which we require additional information and clarification. Please provide responses to the enclosed request for additional information within 30 days of the date of this letter. In accordance with 10 CFR 50.30(b), your response must be executed in a signed original under oath or affirmation. Following receipt of the additional information, we will continue our evaluation of your request.
If you have any questions regarding this review, please contact me at (301) 415-1127.
Sincerely,
/RA/
Alexander Adams, Jr., Senior Project Manager Research and Test Reactors Branch A Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No. 50-139 License No. R-73
Enclosure:
As stated cc w/enclosure: See next page DISTRIBUTION:
Public RidsNrrDpr RidsNrrDprPrta RidsNrrDprPrtb CGlenn ADAMS ACCESSION NO.: ML070320408 TEMPLATE No.: NRR-088 OFFICE PRTA:PM PRTA:LA PRTA:BC PRTA:PM NAME AAdams:cah EHylton DCollins AAdams DATE 02/02/07 02/01/07 02/05/07 02/07/07 OFFICIAL RECORD COPY
University of Washington Docket No. 50-139 cc:
Dr. M. Carette, Assistant to the Dean College of Engineering University of Washington Box 352180 Seattle, WA 98195-2180 Stanley Addison, Radiation Safety Officer Environmental Health and Safety University of Washington Hall Health Center Box 354400 Seattle, WA 98195-4400 Elizabeth Kane, Project Manager Capital Projects Office University of Washington University Facilities Annex 2 Box 352205 Seattle, WA 98195-2205 Dr. Mani Soma, Acting Dean College of Engineering University of Washington P.O. Box 352180 Seattle, WA 98195-2180 Test, Research, and Training Reactor Newsletter University of Florida 202 Nuclear Sciences Center Gainesville, FL 32611
REQUEST FOR ADDITIONAL INFORMATION UNIVERSITY OF WASHINGTON RESEARCH REACTOR FINAL STATUS SURVEY REPORT DOCKET NO. 50-139
- 1. The cited nominal efficiency values for Alpha Gas Proportional detectors in Tables 5-1 and 5-2 and the text in Section 5.3.1.1 are inconsistent. The nominal efficiency values should be consistent in the document, and the associated Minimum Detectable Activities (and Probabilities of Detection) should be calculated using the same efficiency value for a given instrument combination/measurement type. Please update this information to be consistent.
- 2. Section 5.3.2, Instrument Calibration, does not include a discussion of calibration sources (isotope, material, and geometry) and source-to-detector distance for each type of radiation measurement (alpha, beta, gamma). Please provide this information.
- 3. Section 7.1.3.3 describes the use of a 50 cm2 air proportional detector for assessing total alpha activity inside the fuel storage tubes (10 cm diameter). Table 7-2 describes three elevated alpha activity results and the associated weighted average. Please provide the source-to-detector distance and the method of determining the net results in dpm/100 cm2 (e.g., was the measurement result doubled since the detector is 50 cm2 in area?). Discuss if the source-to-detector distance results in an underestimation or overestimation in the efficiency and results.
- 4. Section 4.3.2 of the Decommissioning Plan states that "For direct methods of surface monitoring, the scanning speed will be slow enough to ensure a source detection probability of at least 25% of the guideline level." The calculated scan MDC for beta surface activity, as specified in Table 3-3 of the Final Site Survey Plan (FSSP), is less than 25% of the release criteria for gas proportional detectors, but is not less than 25%
of the release criteria for beta friskers. Furthermore, the scan MDC for alpha surface activity specified in Table 3-3 of the FSSP is 160 dpm/100 cm2, which is not less than 25% of the release criteria. Standard final site survey instrumentation is typically not capable of detecting radioactivity at 25% of the Regulatory Guide 1.86 release criteria when utilized for scanning, nor is there a regulatory requirement that scanning instrumentation should be capable of detecting radioactivity at these levels. Please develop and submit a technical basis to justify the deviation from the requirements of the DP or revise the DP accordingly. If you revise the DP, please submit a copy of the revision paperwork.
- 5. Because of your revision to release criteria that occurred after NRCs site visit to account for tritium, please collect and submit additional measurements around two locations of interest on the bioshield floor (grid location B,1) and bioshield interior south wall (grid location E,-1), to verify that the square-meter average is less than the modified average beta contamination limit of 1,700 dpm/100 cm2. The individual measurement results for these locations were 3,700 and 1,800 dpm/100 cm2, respectively.