Information Notice 2014-09, Spent Fuel Storage or Transportation System Mis-loading
| ML14121A469 | |
| Person / Time | |
|---|---|
| Issue date: | 06/20/2014 |
| From: | Camper L, Michael Cheok, Kokajko L, Mark Lombard NRC/FSME/DWMEP, NRC/NMSS/SFST, Division of Construction Inspection and Operational Programs, Division of Policy and Rulemaking |
| To: | |
| M Banic, NRR/ DPR, 301-415-2771 | |
| References | |
| TAC ME6799 IN-14-009 | |
| Download: ML14121A469 (6) | |
ML14121A469 UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS
OFFICE OF NEW REACTORS
OFFICE OF FEDERAL AND STATE MATERIALS
AND ENVIRONMENTAL MANAGEMENT PROGRAMS
WASHINGTON, DC 20555-0001
June 20, 2014
NRC INFORMATION NOTICE 2014-09:
SPENT FUEL STORAGE OR TRANSPORTATION
SYSTEM MISLOADING
ADDRESSEES
All holders of an operating license or construction permit for a nuclear power reactor under
Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of
Production and Utilization Facilities, including those that have permanently ceased operations
and have spent fuel stored in spent fuel pools (SFPs).
All holders of or applicants for a combined license issued under 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants.
All holders of or applicants for a certificate of compliance (CoC) for a spent fuel transportation
package design under 10 CFR Part 71, Packaging and Transportation of Radioactive Material.
All holders of or applicants for a general or site-specific license for storage of spent fuel, or for a
spent fuel storage cask CoC under 10 CFR Part 72, Licensing Requirements for the
Independent Storage of Spent Nuclear Fuel, High-Level Radioactive Waste, and
Reactor-Related Greater Than Class C Waste.
PURPOSE
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to notify
addressees of SFP and spent fuel dry storage cask misloading events. The NRC expects the
recipients to review the information within this IN for applicability to their facilities or cask
designs and consider actions, as appropriate, for their facility or cask design. However, suggestions contained in this IN are not NRC requirements; therefore, no specific action or
written response is required.
DESCRIPTION OF CIRCUMSTANCES
This section describes SFP and spent fuel dry storage cask misloading events. These events
apply to Part 50 and Part 72 licensees. However, because similar operating procedures and
personnel may be used to load transportation casks, the possibility of similar misloads should
also be considered for Part 71 users. Part 50 licensees
Indian Point Unit 2
The Indian Point Unit 2 technical specifications (TS) require fresh fuel in one area of the SFP to
be stored with one face of the fuel bundle facing adjacent empty storage cells. On
February 17, 2012, the licensee discovered that 11 fresh fuel assemblies that had been moved
into that area between January 23 and 24, 2012, were stored in a manner inconsistent with the
TS in that those 11 fresh fuel assemblies were stored with at least one face adjacent to a
depleted fuel assembly. This error stemmed from incorrect Reactor Engineering move sheets
issued that month. The verifier and preparer did not review the TS thoroughly, thus resulting in
poor self and peer checking and reviewing. The licensee put corrective actions into place to
correct the misload with a new Fuel Assembly Transfer Form (FATF) and other performance
actions. The licensee developed training to reinforce TS compliance and independent
verification and self checking.
Oconee Units 1 and 2
On June 10, 2009, the licensee found that there had been three prior instances of spent fuel
assemblies being incorrectly stored within the SFP, thus violating requirements listed in the TS.
These three instances occurred in the shared SFP for Units 1 and 2 during refueling outages.
The three misloads existed for approximately 1 week to 1 month before the licensee corrected
the issue. According to the TS, once a licensee finds a misload, it must be corrected
immediately. Duke Energy, the licensee, concluded that these instances were not corrected in
a proper timeframe relative to the required completion time or in a timely manner. As corrective
actions, the licensee revised applicable fuel handling procedures to ensure future storage
configuration changes are valid before fuel handling.
Sequoyah Units 1 and 2
The licensee improperly stored four spent fuel assemblies in the SFP in violation of Sequoyah
TS for criticality control requirements during an October 2009 SFP reconfiguration campaign, which was done to maintain conformance with the SFP decay heat dispersion requirements.
The licensee incorrectly placed these four spent fuel assemblies because the FATFs did not
properly incorporate the criticality requirements found in the TS. Once this nonconformance
was discovered, the licensee took corrective actions to relocate the four misplaced spent fuel
assemblies to comply with the TS. The root cause of this misplacement was insufficient
procedural guidance involved in designing the SFP configuration and creating the FATFs.
South Texas Unit 2
On October 16, 2008, while planning fuel movements for South Texas Unit 2 SFP, the licensee
found a Category 11 fuel assembly in a location where the TS only allowed Category 9 fuel.
The licensee removed the Category 11 fuel assembly and placed it in a location of the SFP with
no adjacent fuel assemblies. This misplacement was determined to stem from an error
mapping the SFP storage configuration. In turn, this mapping was used for creating fuel transfer forms (FTF). Both the FTF preparer and verifier did not perform proper checking and
review. This led to the moving of a Category 11 assembly adjacent to Category 9 assemblies, which violate the TS.
Zion Units 1 and 2
On July 13, 2011, the licensee improperly stored the fuel assembly in the spent fuel pool for
Zion Units 1 and 2, where a two-region configuration had been installed. While reviewing
records during a site training class, the licensee determined that a fuel rod storage canister
(FRSC) was incorrectly stored in Region 2 of the SFP. The licensee determined that 9 of the
13 fuel rods contained in the FRSC did not satisfy the requirements to allow Region 2 rack
storage. This FRSC storage was considered a violation of permanently defueled TS, and the
licensee initiated immediate relocation to SFP Region 1.
Part 72 licensees
Palisades
The licensee determined in November 2000 that 11 spent fuel assemblies had been incorrectly
placed into five Ventilated Storage Casks (VSC-24) at the Palisades Plant during the June 1999 to August 1999 spent fuel loading campaign. The CoC required the assemblies to undergo 5 years of cooling following their discharge from the reactor core before being loaded in the cask.
However, the assemblies in question had cooled for just over 4 years. The licensee determined
that the event was caused by an error in recording the core discharge dates for these
assemblies. As part of the corrective actions, the licensee modified the fuel selection process to
include a specific procedure for fuel selection. In addition, the licensee upgraded the reactor
engineering fuel management file to include fuel cycle date information.
Grand Gulf
On June 18, 2008, during a data update of the Cask Loading Database, the licensee discovered
that four HI-STORM 100 model casks had been incorrectly loaded with fuel bundles that
exceeded limits specified in the CoC. The licensee found that, due to errors in the Cask
Loading Database, 8 assemblies exceeded the individual assembly decay heat or exposure
limits allowed in the CoC. The database contained incorrect bundle exposures for the affected
assemblies. During the time in which the licensee was identifying these errors, the decay heat
loads for all of the assemblies in question had been verified to be within the CoC limits. As a
result of this event, the licensee developed a standard procedure for developing the necessary
databases and calculations for selecting and analyzing spent fuel cask loads and for addressing
the scope and method for performing the independent verification. North Anna and Surry
In March 2011, during a review of historical NUHOMS dry storage canister (DSC) loading
certification documents for North Anna and Surry, the licensee discovered that a number of
DSCs were incorrectly loaded. The cask design included asymmetrical decay heat limits that
were not adequately described in the written cask loading procedures, leading to repeated
errors in the loading process. These errors resulted in 17 assemblies exceeding the maximum
decay heat limits for their respective canister locations. The licensees corrective actions
involved revising procedures to include an explanation of the asymmetrical decay heat limits.
BACKGROUND
Appendix A to 10 CFR Part 50, General Design Criteria for Nuclear Power Plants, Criterion 62, Prevention of Criticality in Fuel Storage and Handling, requires Criticality in the fuel storage
and handling system shall be prevented by physical systems or processes, preferably by use of
geometrically safe configurations. Additionally, regulations in 10 CFR 50.68, Criticality
Accident Requirements, contain criteria that a licensee must meet to ensure that the pool is
maintained subcritical at all times.
For dry cask storage, 10 CFR 72.124(a) requires that:
Spent fuel handling, packaging, transfer, and storage systems must be designed
to be maintained subcritical and to ensure that, before a nuclear criticality
accident is possible, at least two unlikely, independent, and concurrent or
sequential changes have occurred in the conditions essential to nuclear criticality
safety. The design of handling, packaging, transfer, and storage systems must
include margins of safety for the nuclear criticality parameters that are
commensurate with the uncertainties in the data and methods used in
calculations and demonstrate safety for the handling, packaging, transfer and
storage conditions and in the nature of the immediate environment under
accident conditions.
DISCUSSION
Both the SFP licenses and the spent fuel dry storage cask CoCs contain storage requirements
for spent and fresh nuclear fuel. Those requirements are based on NRC reviewed and
approved analyses that, if adhered to, will provide reasonable assurance of compliance with the
applicable storage regulations. Failure to adhere to those requirements places the fuel storage
system in an unanalyzed condition and could lead to a potential safety concern.
The above events show that misloading of fuel assemblies into SFPs and spent fuel dry storage
casks can occur as a result of inadequate procedures or training. SFP and spent fuel dry
storage cask loading requirements can be quite complex, often with several different sets of
criteria that must be met simultaneously.
CONTACT
This IN requires no specific action or written response. Please direct any questions about this
matter to the technical contacts listed below or the appropriate NRC project manager.
/RA/
/RA/
Michael C. Cheok, Director
Lawrence E. Kokajko, Director
Division of Construction Inspection
Division of Policy and Rulemaking
and Operational Program
Office of Nuclear Reactor Regulation
Office of New Reactors
/RA by Andrew Persinko for/
/RA by Anthony H. Hsia for/
Larry W. Camper, Director
Mark Lombard, Director
Division of Waste Management
Division of Spent Fuel Storage
and Environmental Protection
and Transportation
Office of Federal and State Materials
Office of Nuclear Material Safety
and Environmental Management Programs
and Safeguards
Technical Contacts: Kent A. Wood, NRR/DSS
301-415-4120
Email: kent.wood@nrc.gov
Note: NRC generic communications may be found on the NRC public Web site, http://www.nrc.gov, under Electronic Reading Room/Document Collections.
TAC ME6799 *concurred via email
OFFICE
NRR:DSS/SRXB/SFT
NRR:DSS/SRXB/SFT
TECH EDITOR*
NRR:DSS/SRXB*
NRR/DSS*
NAME
DCunanan
KWood
JDougherty
CJackson
TMcGinty
DATE
5/22/2014
5/22/2014
4/29/2014
5/31/2014
5/30/2014 OFFICE
NMSS/DSFST/CSDAB*
NRR/DPR/PGCB*
NRR/DPR/PGCB
NRR/DPR/PGCB
NRO/DCIP
NAME
MRahimi
CHawes
MBanic
SStuchell
MCheok
DATE
5/28/2014
6/3/2014
6/3/14
6/5/2014
6/5/2014 OFFICE
FSME/DWMEP
NMSS/DSFST
NRR/DPR
NRR/DPR
NAME
LCamper (APersinko for)
MLombard (AHsia for)
SBahadur
LKokajko
DATE
6/13/2014
6/10/2014
6/17/2014
6/20/2014