NLS2005071, 10 CFR 71.95 Report of Failure to Meet Conditions in Certificate of Compliance During Radioactive Material Shipment Cooper Nuclear Station
| ML052590337 | |
| Person / Time | |
|---|---|
| Site: | Cooper, 07109233  |
| Issue date: | 09/06/2005 |
| From: | Minahan S Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, NRC/NMSS/SFPO |
| References | |
| NLS2005071 | |
| Download: ML052590337 (7) | |
Text
N Nebraska Public Power District Always there when you need us NLS200507 1 September 6, 2005 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Director, Spent Fuel Project Office Office of Nuclear Material Safety and Safeguards Washington, D.C. 20555-0001
Subject:
10 CFR 71.95 Report of Failure to Meet Conditions in Certificate of Compliance During Radioactive Material Shipment Cooper Nuclear Station, Docket 50-298, DPR46 The purpose of this correspondence is to forward a report in accordance with 10 CFR 71.95 concerning an instance in which the conditions in the certificate of compliance were not met during a radioactive material shipment.
Sincerely, art . inahan General Manager of Plant Operations
/em Attachment cc: Chief Engineer w/ attachment NPG Distribution xv/attachment Transnuclear, Inc Regional Administrator xv/attachment CNS Records w/attachment USNRC - Region IV Senior Project Manager w/attachment USNRC - NRR Project Directorate IV-I Senior Resident Inspector xv/attachment USNRC-CNS COOPERNUCLEARSTATION P.O. Box 98/ Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 www.nppd.corn
NLS2005071 Attachment Page I of 5 10 CFR 71.95 Report Radioactive Debris Found Betwveen TN-RAM Cask and Liner Results in Failure to Meet Conditions in Certificate of Compliance ABSTRACT On July 8, 2005, at 9:15 a.m., Chem-Nuclear Systems, L.L.C. in Barnwell, South Carolina, notified Cooper Nuclear Station (CNS) of a condition discovered during off-loading of a TN-RAM shipping cask. A small piece of radioactive metal debris 1/4 inch by 1/4 inch in size was discovered between the outer wall of the inner TN-RAM liner and the inner wall of a TN-RAM shipping cask. The cask had come from CNS in shipment #05-10. It was the first TN-RAM liner from the current fuel pool cleanup project. The metal debris emitted radiation at a rate of 70 Rem/hour at contact. Technicians at Barnwell removed the metal debris from the TN-RAM cask interior and placed it in a 30-gallon drum for temporary storage pending ultimate disposal. The CNS Radiation Protection Manager curtailed shipments of casks from CNS and suspended use of the related shipping procedure until the root cause was determined and corrective actions implemented.
NARRATIVE DESCRIPTION OF EVENT
Background
The following is the sequence of events leading to the discovery of the small piece, 1/4 inch by 1/4 inch, of radioactive metal debris with an activity of 70 Rem/hour between the liner and the inner wall of a TN-RAM shipping cask.
Prior to transporting the TN-RAM cask to Cooper Nuclear Station (CNS), Chem-Nuclear personnel surveyed the TN-RAM cask, including its interior, at their facility. No radiological anomalies were detected.
On June 20, 2005, CNS received the TN-RAM cask in question. CNS personnel surveyed the cask exterior for radiation. No anomalies were detected. The liner was moved from the cask pad area to another pad. This area had not been vacuumed, but had been examined for foreign debris.
Equipment was removed from the fuel pool, and other stored items in the fuel pool were moved to allow placement of the cask on the fuel pool floor.
On June 21, 2005, the cask was moved to the refuel floor. Because scaffolding had not yet been erected, the lid was not removed and the cask internals were not inspected at that time.
On June 22, 2005, after erecting scaffolding for cask handling and installing the cask seal protector, the cask o-ring test port plug was removed, the vent and drain covers were removed, and dose rates were surveyed and recorded. The cask lid was removed from the cask body. The open cask cavity was visually inspected, and no problems were noted. The internals of the cask were inspected using a high intensity lamp, and no debris was observed. Dose rates were measured at the plane of the cask opening and were normal.
- NLS2005071 Attachment Page 2 of 5 The cask was lifted, the bottom protector installed, and the cask was placed in the spent fuel pool in the designated area on the pool floor. The cask, lift beams, and the main hook and block wvere rinsed with de-mineralized water as they were lowered into the pool, and the lift beams were rinsed when removed from the pool.
After placing irradiated components and debris into the liner, the exterior of the liner was inspected by camera. No debris items were found on the exterior of the liner, including the bottom. After the inspection of the liner exterior, the liner was placed in the cask. No binding wvas noted, and the cask lid was installed. The cask and liner were secured, removed from the spent fuel pool while being rinsed, drained, dried, and otherwise prepared for transport by truck.
On June 23, 2005, the cask was de-contaminated using strip coat paint. Radiation surveys were performed with no abnormal indications. The cask was taken to a truck trailer, loaded in the horizontal position, and transported to Barnwell, South Carolina. This was the first shipment of material associated with the spent fuel pool clean up project from CNS to Barnwell. This was not the first time CNS had used TN-RAM containers to transport material.
Event Description On July 8, 2005, upon receipt of the TN-RAM Cask, Chem-Nuclear personnel detected radioactive debris between the cask and liner and documented the condition in their corrective action program. During a radiation survey of the interior of the cask, a dose rate of 35 Rem/hour was detected with a teletector. Visually, a small, rusty colored metal object about 1/4 inch by 1/4 inch was found stuck on the cask %vallat the 4 to 5 o'clock position. The object was removed from the cask, placed in double plastic bags, and was then placed in a 30-gallon drum for temporary storage. The contact dose rate of the item was 70 Rem/hour, and the dose rate at a distance of 1 foot was 3 Rem/hour.
Chem-Nuclear personnel concluded that the item constituted a shipping discrepancy of South Carolina Department of Health and Environmental Controls Radioactive Material License 097, Condition 61, which states that loose radioactive waste and solidification residuals within shipping casks are prohibited. Chem-Nuclear notified CNS of their finding and that Department of Transportation exposure limits were not violated.
Basis for Report This event is reportable under 10 CFR 71.95(b) as an instance in which the conditions in the certificate of compliance were not followed during a shipment. This shipment failed to follow the conditions of Certificate of Compliance (CofC) No. 9233 for Model No. TN-RAM Package, Revision 7, Docket Number 71-9233. Section 5(b)(1) of the CofC identifies the type of material which may be shipped under this certificate as dry irradiated and contaminated non-fuel-bearing solid materials contained within a secondary container. The debris found was not contained within the secondary container, the liner.
NLS2005071 Attachment Page 3 of 5 Safetv Consequences and Implications This event had no effect on nuclear or public safety. Exposure of individuals to radiation or to radioactive materials was negligible. The piece of radioactive debris found between the cask and liner was not a radiological threat to the public because of the shielding provided by the cask and the controls applied during shipping. It was not a radiological threat to on-site personnel, because of the controls applied and survey results at CNS and Barnwell. It was no threat to the environment because radioactive material was contained or controlled and not released to the environment.
Quantities and Chemical and Physical Form(s) of Contents Volume of Waste ... 5.94 ft3 Weight of Waste ... 2581.4 lbs Chemical Form .... Solid/Metal/Metal Oxides Radioactive Content Isotope mCi Isotope mCi H-3 1.15E3 Ag-I 10m 1.88E1 C-14 1.01133 Sb-124 5.72E-1 Cr-51 1.27E4 Sb-125 1.63E4 Mn-54 7.71E4 Te-125m 2.26E3 Fe-55 3.90E6 Cs- 134 1.66E-2 Fe-59 1.52133 Cs-137 3.36E-2 Co-58 1.23E4 U-235 3.96E-5 Co-60 7.00E6 Np-237 7.27E-4 Ni-59 3.411E3 Pu-238 7.98130 Ni-63 6.51 E5 Pu-239 5.36E-3 Zn-65 1.44E I Pu-240 6.26E-3 Sr-89 1.21 E0 Pu-241 1.05130 Sr-90 1.1 OE-2 Am-241 7.22E-3 Zr-95 4.34E-6 Am-243 1.60E-4 Nb-94 1.92EI Cm-242 6.98E-2 Nb-95 3.62E-1 Cm-243 1.79E-4 Tc-99 3.70130 Cm-244 2.68E-2 Cause No systems or components related to this event failed.
The root cause of the debris entering the cask was a deficient procedure used to control cask loading activities on the refuel floor and in the spent fuel pool. It did not contain sufficient provisions to prevent debris that may be resting on seismic steel structures or other ledges and
NLS2005071 Attachment Page 4 of 5 edges from becoming dislodged by water motion and falling into the cask when it is open and immersed in the fuel pool. Additionally, it does not contain sufficient quality assurance inspections to detect when debris has entered the cask prior to it being loaded and closed.
The root cause investigation determined that wave action and water movements, caused by moving the cask or liner, most likely caused small debris items with relatively large surface areas to move about in the water. If such debris items were laying on upward facing surfaces on the seismic steel structure in the spent fuel pool, located above the work area, such water movements could dislodge the items and allow them to drift downwards into the open cask.
Documented radiation checks at Barnwell, prior to shipping the TN-RAM container to CNS, and visual checks at CNS after it was received preclude the radioactive debris item originating somewhere other than CNS. Visual examination of the debris item at Barnvell verified it had the same appearance as debris created at CNS during the crushing and shearing work that was done in the same area of the pool prior to the TN-RAM cask being prepared for shipping.
No inspection for debris in the cask was made after the cask was put into the spent fuel pool.
Further, no inspection was made for debris in the cask after the liner was moved and lifted into position for loading into the cask. An inspection for debris on the liner exterior was made when the liner was lifted and positioned for loading into the cask. No debris was found on the liner exterior.
The procedure being used at the time, NUKEM 1016, revision 6, was found to have several deficiencies. It does not require a camera check inside the cask after the cask has been placed in the pool. Thus, debris could fall or drift undetected into the cask after it is placed in the pool. It does not require a camera check inside the cask just before the liner is loaded into it. Thus, debris could fall or drift undetected into the cask after having been stirred up by movement of the liner through the pool. While the procedure does require that the floor be vacuumed for debris, it does not require that the seismic steel structure above the floor be vacuumed for debris. The procedure only required one person to visually inspect the cask and liner by camera.
A contributing cause of the event was a self-checking failure that occurred with respect to evaluation of industry operating experience (OE). When an OE report from another plant experiencing a similar event was reviewed at CNS no action was taken to prevent its occurrence at CNS, nor was the OE re-directed to another appropriate party to review.
CNS also found the Project Management procedure does not incorporate OE checks to look for useful industry experience.
Correctivc Actions
NLS2005071 Attachment Page 5 of 5
- 2. The shipping procedure related to this event, NUKEM 1016, revision 6, was put on administrative hold to require revision incorporating corrective actions prior to performing another shipment.
- 3. NUKEM Procedure 1016 is being revised to contain: 1) a requirement to vacuum the seismic steel structure to remove any debris that may be present in addition to other vacuuming and debris clean up activities already being done, 2) a requirement to inspect the interior of the cask by camera for debris after it is placed in the spent fuel pool and water movement has subsided, 3) a requirement to inspect the interior of the cask by camera for debris after the liner is moved and positioned for loading into the cask and water movement has subsided, and 4) a requirement for two, independent observers to watch the camera monitor when inspections are done, and to record the inspection by VHS, DVD, or similar format, for quality verification purposes.
- 4. The CNS procedure governing Project Management was revised to include a requirement to check for relevant industry OE.
- 5. Projects being planned and projects whose execution is not yet complete were checked for relevant OE that may apply to them.
These corrective actions have been completed except for Action #3 which is pending approval in mid-September and is being tracked in the CNS corrective action program. No radioactive shipments using the TN-RAM cask will be made until the revised NUKEM 1016 procedure is approved and implemented.
Previous Events No previous instances of failing to follow the conditions in CofC have occurred at CNS. The extent of condition with respect to shipping radioactive materials under procedure NUKEM 1016, revision 6, was limited to this event. Other recent shipments of radioactive materials used dry containers that do not involve the filling of liners while immersed in the spent fuel pool.
Name and Telephone Number of Knowlcdgcablc Person The name and telephone number of the person at CNS who is knowledgeable about the event and can provide additional information is as follows.
Robert J. McDonald (402) 825-5235
I ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS© I Correspondence Number: NLS2005071 The following table identifies those actions committed to by Nebraska Public Power District (NPPD) in this document. Any other actions discussed in the submittal represent intended or planned actions by NPPD. They are described for information only and are not regulatory commitments. Please notify the Licensing Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.
COMMITMENT COMMITTED DATE COMMITMENT NUMBER OR OUTAGE None I 4 I 4 I 4 I PROCEDURE 0.42 l REVISION 18 l PAGE 19 OF25