ML20058Q370
| ML20058Q370 | |
| Person / Time | |
|---|---|
| Site: | Fort Saint Vrain  |
| Issue date: | 12/21/1993 |
| From: | Warembourg D PUBLIC SERVICE CO. OF COLORADO |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20058Q373 | List: |
| References | |
| P-93120, NUDOCS 9312290059 | |
| Download: ML20058Q370 (5) | |
Text
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Public Service' P.O. Box 840 Denmgo 8 2 840 16805 WCR 19 1/2; Platteville, Colorado 80651 December 21, 1993 Fort St. Vrain Unit No. 1 P-93120 U.
S.
Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C.
20555 Docket No. 50-267
SUBJECT:
Annual Fort St.
Vrain Decoramissioning Plan Upm.e Submittal
REFERENCES:
(See Attached)
Gentlemen:
Thir letter transmits Public Service Company of Colorado's (PSC) first annual update of the Fort St. Vrain (FSV) Decommissioning Plan (DP).
Enclosed is one signed original and ten additional copies of Revision 1 to the FSV DP.
The Proposed Decommissioning Plan was submitted to the NRC in
- November, 1990 (Reference 1).
It was updated in July, 1991 (Reference 2),
then again in April, 1992 (Reference 3).
The Nuclear Regulatory Commission (NRC) approved the Proposed Decommissioning Plan in the FSV Decommissioning Order (Reference 4) in November, 1992.
The FSV Decommissioning Order states:
"The Decommissioning Plan replaces the licensee's Updated Safety Analysis Report.
Acccrdingly, a license condition has been added allowing the licensee to make changes to the Decommissioning Plan after performing a review based upon criteria similar to the criteria of 10 CFR 50.59 to ensure that such changes do not involve an unreviewed safety question."
In addition, the FSV Decommissioning Order require PSC to submit to the NRC a quarterly report containing a brief description of any changes, tests and experiments, including a summary of the safety evaluation of each.
References 5 through 8 are the quarterly reports of changes, tests and experiments submitted during the first year following issuance of the FSV Decommissioning Order.
2@ * " n 9312290059 931221 0h DR ADOCK 05000267 [2 PDR b
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i P-93120 December 21, 1993 Page 2 The enclosed DP has been updated to reflect the changes discussed in these quarterly reports.
Brief descriptions of the principal changes to af fected sections of the DP, Revision 1,
are included in Attachment A.
Revisions entered since the Proposed Decommissioning Plan was last updated (Reference 3) are identified with a bar mark in the margin adjacent to the portion actually changed.
If you have any questions concerning this report, please contact Mr. M.
H. Holmes at (303) 620-1701.
Sincerely, "f]'f(LL O
U
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D.
W.
Warembourg Decommissioning Program Director DWW/JRJ Enclosure cc:
Mr. John H. Austin, Chief Decommissioning and Regulatory Issues Branch Reg'.onal Administrator, Region IV Mr. Robert M. Quillin, Director Radiation Contn 1 Division
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i P-93120
}
December 21, 1993 Page 3-i REFERENCES
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- 1) PSC Letter dated November 5, 1990, Crawford.to. Weiss (P-90318)
- 2) PSC Letter dated July 1, 1991, Crawford to Weiss (P-91217)
- 3) PSC Letter dated April 17, 1992, Warembourg to Weiss (P-92162) f
- 4) NRC Letter dated November 23, 1992, Erickson to Crawford (G-92244)
- 5) PSC Letter dated March 4,
1993, Warembourg 'to NRC Document-Control Desk (P-93012)
- 6) PSC Letter dated June 9,
1993, Warembourg to NRC Document Control Desk (P-93048) l i
- 7) PSC Letter dated September 9, 1993, Warembourg to NRC Document Control Desk (P-93088)
- 8) PSC Lettet' dated December 9, 1993, Warembourg to NRC Document-Control Desk (P-93113) i 1
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ATTACHMENT A P-93120 December 21, 1993 j
Description of Principle Chances Incornorated in Revision 1 of the Fort St. Vrain Decommissionina Plan Section 1 Included a reference to the FSV Decommissioning Order, noting that it requires the report of changes, tests and experiments to be submitted to the NRC on a quarterly basis.
Section 2 Revised the description of the PCRV Shield Water system to reflect the as-built configuration.
Explained that air displaced from the PCRV during the initial fill operation would be routed directly to the Reactor Building ventilation exhaust system rather than to the Radioactive Gas Waste system for_ sampling prior to release via the Reactor Building ventilation exhaust system.
Indicated that the Reactor Building ventilation exhaust system would take a suction on the PCRV when the PCRV was filled with shield water, so the i
Radioactive Gas Waste system would not be necessary for holdup of gas and could be dismantled / decontaminated relatively early in the j
decommissioning process.
Corrected the description of plans to j
2 remove the core outlet thermocouple assemblies-prior to-flooding the PCRV to explain that these thermocouple assemblies will be i
removed underwater to reduce occupational radiation exposures, in accordance with Amendment No.
87 to the FSV Decommissioning Technical Specifications.
j i
Clarified statements indicating that the Reactor Building overhead crane will be re-reeved and the refueling floor equipment hatch will be enlarged to state that these modifications may be imp 1 emented for operations involving handling of large concrete segments, though they were not necessary for PCRV top head concrete removal.
Revised the description of PCRV top head concrete removal, and associated figures, to indicate that the concrete was sectioned into 12 pie-shaped wedge segments, with the horizontal cut being within approximately one inch of the top head liner.
Revised the description of the decommissioning rotary work platform (DRWP) to indicate that it will have two rather than three access openings, and stated that the DRWP and its associated airborne contamination control system (ACCS) would be installed prior to sectioning and removal of the PCRV top head liner.
Described the as-built configuration of the ACCS system.
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d ATTACHMENT A P-93120 December 21, 1993 Revised information in the text and figures pertaining to removal of graphite blocks from the PCRV.
Whereas the original plans called for removing one-block at a time, the methodology being implemented relies on removal of multiple graphite blocks from the PCRV using transfer _ baskets and a shield bell.
Eliminated descriptions of graphite block dryers, block sectioning stations-and side spacer block boronated pin dumping operations, which are not necessary with the revised block processing methodology.
Section 3 Reflected FSV's exemption to the revised 10 CFR 20 regulation, indicating that decommissioning would be completed under the existing 10 CFR 20 requirements.
Corrected initial estimates of the breakdown of volumes of radioactive waste by waste classification.
Stated that the Rocky Mountain Compact was permitted access to the existing Northwest Compact's low level radioactive waste disposal facility in Richland, Washington, beginning in
- January, 1993.
Reflected the addition of a
Radiochemistry Supervisor and a Training Coordinator to the Westinghouse Team's Radiation Protection organization.
Revised the accident analyses to include the results of the evaluation of postulated worst case drop of a concrete segment removed from the PCRV top head, using identical assumptions to those previously used in the concrete rubble drop accident, with source terms based on actual measurements taken from top head concrete core drills.
In addition, revised-the accident analyses to reflect results of the evaluation of worst case postulated drop of a package containing multiple activated graphite blocks, taking credit for 99% efficiency of the Reactor Building ventilation exhaust system HEPA filters, in accordance with Amendment No. 86 to the FSV Decommissioning Technical Specifications.
This analysis also utilized activity concentrations based on actual samples taken from activated graphite blocks in the PCRV.
Clarified information regarding the probability of a simultaneous occurrence of an earthquake in combination with hoisting a package containing activated graphite blocks.
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