05000133/LER-2010-001, Regarding Lost Radioactive Calibration Standard
| ML102320573 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay |
| Issue date: | 08/20/2010 |
| From: | Becker J Pacific Gas & Electric Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| HBL-10-017 LER 10-001-00 | |
| Download: ML102320573 (8) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 1332010001R00 - NRC Website | |
text
Pacific Gas and Electric Company August 20, 2010 James R. Becker Site Vice President Diablo Canyon Power Plant Mail Code 104/5/601 p. O. Box 56 Avila Beach, CA 93424 805.545.3462 Internal: 691.3462 Fax: 805.545.6445 10 CFR 20.2201 PG&E Letter HBL-1 0-017 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Humboldt Bay Power Plant Unit 3 Docket No. 50-133, OL-DPR-7 Licensee Event Report 2010-001.;.00 Lost Radioactive Calibration Standard
Dear Commissioners and Staff:
In accordance with 10 CFR 20.2201 (b)(2)(ii), Pacific Gas and Electric Company is submitting the enclosed Licensee Event Report regarding the loss of a radioactive calibration standard.
This event did not adversely affect the health and safety of the public.
Enclosure cc/enc: Elmo E. Collins, NRC Regional Administrator, Region IV John B. Hickman, NRC Project Manager Robert J. Evans, NRC PG FossilGen HBPP Humboldt Distribution
NRC FORM 366 (9-2007)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2010 LICENSEE EVENT REPORT (LER)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
(See reverse for required number of digits/characters for each block)
- 1. FACILITY NAME Humboldt Bay Power Plant, Unit 3
- 4. TITLE Lost Radioactive Calibration Standard
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 2. DOCKET NUMBER 05000133
- 13. PAGE I
1 OF 7
- 8. OTHER FACILITIES INVOLVED YEAR I SEQUENTIAL I REV MONTH FACILITY NAME DOCKET NUMBER MONTH DAY YEAR NUMBER NO.
DAY YEAR FACILITY NAME DOCKET NUMBER 06 24 2010 2010 001 00 08 20 2010
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check al/ that apply)
~ 20.2201(b)
D 20.2203(a)(3)(i)
D 50.73(a)(2)(i)(C)
D 50.73(a)(2)(vii)
NA D 20.2201(d)
D 20.2203(a)(3)(ii)
D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A)
D 20.2203(a)(1)
D 20.2203(a)(4)
D 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B)
D 20.2203(a)(2)(i)
D 50.36(c)(1 )(i)(A)
D 50.73(a)(2)(iii)
D 50.73(a)(2)(ix)(A) 1-1-0-. P-O-W-E-R-L-E-V-EL----1D 20.2203(a)(2)(ii)
D 50.36(c)(1)(ii)(A)
D 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x)
D 20.2203(a)(2)(iii)
D 50.36(c)(2)
D 50.73(a)(2)(v)(A)
D 73.71(a)(4)
D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii)
D 50.73(a)(2)(v)(B)
D 73.71(a)(5)
D 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(C)
D OTHER 000 D 20.2203(a)(2)(vi)
D 50.73(a)(2)(i)(B)
D 50.73(a)(2)(v)(D)
Specify in Abstract below or in NRC Form 366A
- 12. LICENSEE CONTACT FOR THIS LER FACILITY NAME ITELEPHONE NUMBER {Include Area Code)
David Sokolsky - Supervisor of Licensing 707-444-0801 CAUSE MANU-SYSTEM COMPONENT FACTURER REPORTABLE TO EPIX
CAUSE
MANU-SYSTEM COMPONENT FACTURER REPORTABLE TO EPIX NA
- 14. SUPPLEMENTAL REPORT EXPECTED D YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
NA
~NO ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)
- 15. EXPECTED SUBMISSION DATE MONTH DAY YEAR On June 24, 2010, while conducting the quarterly inventory of radioactive sources in accordance with Humboldt Bay Power Plant (HBPP) Unit 3 Radiation Control Procedure (RCP) 60, "Inventory and Controls for Radioactive Sources," it was discovered that source number HBS-498 was missing from the count room. HBS-498 is a mixed gamma source with an activity of 0.35 micro-curies as of August 9, 2010, and is used for the calibration of gamma detectors. The calibration source radionuclide composition yields an aggregate quantity of missing licensed material of 53 times the quantity specified in 10 CFR 20 Appendix C, which exceeds the reporting criterion of 10 times the quantity specified in Appendix C.
An extensive search has not been successful in locating the source to date.
The root cause for this event has been determined to be inadequate Radiation Protection procedures to ensure control of radioactive sources. RCP-60 is being revised to strengthen the source control process.
NRC FORM 366 (9-2007)
PRINTED ON RECYCLED PAPER (9-2007)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATH'lN SHEET FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR SEQUENTIAL NUMBER REVISION NUMBER Humboldt Bay Power 0 5 0 0 0 1 3 3 2010 Plant, Unit 3 o 0 1
o 0 2
OF TEXT I.
Plant Conditions
Humboldt Bay Power Plant (HBPP) Unit 3 was shut down in 1976. Spent fuel transfer to the Independent Spent Fuel Storage Installation (ISFSI) was completed in December, 2008. Unit 3 is currently decommissioning, with decontamination and dismantlement in progress.
II.
Description of Problem A.
Background
On June 24, 2010, during the quarterly inventory of radioactive sources by HBPP radiation protection (RP) personnel, it was discovered that source number HBS-498 was missing. HBS-498 is a glass fiber filter paper with a mixed radionuclide gamma emitting composition. This source is used for specific radiation instrument calibrations. It was previously accounted for in the April 8, 2010, inventory. It is not definitively known that the source was not in use between the April and June inventories; however, to the best knowledge of RP personnel, it had not been used for any purpose between these inventories. An exhaustive search for the missing source was commenced following the discovery and was continued for approximately one month without success.
B.
Event Description
(i)
A description of the licensed material involved, including kind, quantity, and chemical and physical form:
Source number HBS-498A is a glass fiber filter paper, mixed radionuclide gamma source used for specific radiation instrument calibrations. The source activity was 0.35 micro-curies as of August 9, 2010.
The radionuclide composition of the source is as follows:
7 (9-2007)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATIIDN SHEET FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR SEQUENTIAL NUMBER REVISION NUMBER Humboldt Bay Power 0 5 0 0
0 1 3 3 2010 Plant, Unit 3 o 0 1
o 0 3
TEXT Nuclide Activity (Curies)
Am-241 5.27E-OB Cd-109 2.25E-07 Co-57 2.27E-09 Ce-139 4.96E-10 Hg-203 6.0BE-13 Sn-113 4.0BE-10 Cs-137 1.90E-OB Y-BB 4.71E-10 Co-60 2.41 E-OB (ii)
A description of the circumstances under which the loss or theft occurred:
On June 24, 2010, during the quarterly inventory of radioactive sources by HBPP RP personnel, it was discovered that source HBS-498 was missing. The source was previously accounted for in the April 8, 2010, inventory. It is not definitively known that the source was not in use between the April and June inventories, but to the best knowledge of RP personnel, it had not been used for any purpose between these inventories.
(iii)
A statement of disposition, or probable disposition, of the licensed material involved:
Several scenarios were considered. Based upon both the circumstances surrounding the loss and the preliminary results of a PG&E Corporate Security investigation, it has been concluded that the two most likely scenarios are that the source was inadvertently disposed of as dry radioactive waste or that the source is still in the radiologically controlled area (RCA) in some yet to be identified location. Another scenario discussed, but considered less likely, was that an individual either inadvertently or intentionally exited the RCA with the source on his/her person. The source went undetected because of its low dose rate.
OF 7 (9-2007)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATI ~N SHEET FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR SEQUENTIAL NUMBER REVISION NUMBER Humboldt Bay Power 0 5 0 0 0 1 3 3 2010 Plant, Unit 3 o 0 1
o 0 4
TEXT (iv)
Exposures of individuals to radiation, circumstances under which the exposures occurred, and the possible total effective dose equivalent (TEOE) to persons in unrestricted areas:
The calculated effective dose equivalent (EOE) is for the less likely scenario (Le., an individual left the RCA with the source on his/her person and because the dose rate was so low it went undetected).
The resultant TEOE would be several millirem with the assumptions made about time and source location on the individual.
(v)
Actions that have been taken, or will be taken, to recover the material:
An exhaustive search for the missing source was commenced and continued for approximately one month. Multiple locations were checked and rechecked without success. The search included item-by-item inspection of the contents of numerous bags of dry radioactive waste. A portable gamma spectrometry system (the Canberra In Situ Object Counting System (ISOCS)) was utilized in searching the dry radioactive waste. It was hoped the source would be found by identifying its Cadmium-109 gamma, which is not a constituent of the HBPP waste stream. This proved unsuccessful. No record that the source had been retired was located, nor was the source found in the source disposal drum.
(vi)
Procedures or measures that have been, or will be, adopted to ensure against a recurrence of the loss or theft of licensed material:
Unit 3 Radiation Control Procedure RCP-60, "Inventory and Controls for Radioactive Sources," is being revised to require the following:
Locking sources in designated storage lockers when not in use Logging sources in and out Peer checks when logging sources in and out C.
Status of Inoperable Structures, Systems, or Components that Contributed to the Event NA OF 7 (9-2007)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR SEQUENTIAL NUMBER REVISION NUMBER Humboldt Bay Power 0 5 0 0 0 1 3 3 2010 Plant, Unit 3 o 0 1
o 0 5
TEXT O.
Other Systems or Secondary Functions Affected
None E.
Method of ~iscovery Performance of the quarterly source inventory per Unit 3 Radiation Control Procedure RCP-60, "Inventory and Controls for Radioactive Sources" F.
Operator Actions
None G.
Safety System Responses None III.
Cause of the Problem A.
Immediate Cause Radioactive Source HBS-498 could not be located during the performance of the quarterly inventory on June 24, 2010.
B.
Root Cause Radiation Protection procedures were inadequate to ensure control of radioactive sources.
IV.
Assessment of Safety Consequences
There are no safety consequences as a result of this event because of the minor dose consequences to an individual if it is assumed that the individual removed the source from the RCA. There will also be no dose consequences if the source remains in the RCA or has been disposed of as dry radioactive waste.
V.
Corrective Actions
A.
Immediate Corrective Actions
HBPP sources were locked in storage lockers and a policy to log sources OF 7 (9-2007)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR SEQUENTIAL NUMBER REVISION NUMBER Humboldt Bay Power 0 5 0 0 0 1 3 3 2010 Plant, Unit 3 o o 1
o o 6 TEXT in and out was established. This event was discussed with Radiation Protection and Instrument Technicians, as were the new policy requirements to store and lock sources in the designated storage lockers when not in use, and to log sources out and in prior to and following use, respectively.
B.
Corrective Actions to Prevent Recurrence Procedure RCP-60, "Inventory and Controls for Radioactive Sources," is being revised to require the following:
Locking sources in designated storage lockers when not in use Logging sources in and out Peer checks when logging sources in and out VI.
Additional Information
A.
Failed Components NA B.
Previous Similar Events
License Event Reports:
LER 2004-001-00: In 2003, PG&E identified a discrepancy in plant records that called into question the location of three 18-inch segments of a single spent fuel rod. An extensive investigation did not definitively locate these segments. Due to the wide disparity in radiation levels between the two types of material (fuel rod segments versus a calibration standard), the more generic issue of radioactive "source" control was not identified during the cause analysis of the 2003 event.
Notifications (Problem Reports):
1204330 (2/4/1999): A Co-60 whole body counter check source was inadvertently removed from the site by a radiation protection technician.
The source was normally used outside of the RCA. No potentially generic impacts to sources located within the RCA were identified.
1206771 (8/19/1999): A whole body counter source was missing. The source was not marked as "radioactive" and was discarded in the trash, OF 7 (9-2007)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATIDN SHEET FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR SEQUENTIAL NUMBER REVISION NUMBER Humboldt Bay Power 0 5 0 0 0 1 3 3 2010 Plant, Unit 3 o 0 1
o 0 7
TEXT where it was later was recovered. Corrective actions were limited to notification of the vendor and marking the source as radioactive.
C.
Industry Reports INPO Nuclear Network Event OE 22090 (12/27/2005): "Loss of Radioactive Sources due to Inadequate Administrative Controls" Five radioactive sources, including two Am-241 sources, were discovered missing during an annual inventory. There were no administrative controls, such as logging out or in of sources, for RP use.
OF 7