ML060250261
| ML060250261 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 01/26/2006 |
| From: | Nerses V NRC/NRR/ADRO/DORL/LPLB |
| To: | Darrell Roberts NRC/NRR/ADRO/DORL/LPLB |
| Nerses V, NRR//DLPM, 415-1484 | |
| References | |
| TAC MC8327 | |
| Download: ML060250261 (5) | |
Text
January 26, 2006 MEMORANDUM TO: Darrell J. Roberts, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM:
Victor Nerses, Senior Project Manager /RA by G. Edward Miller for/
Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
MILLSTONE POWER STATION, UNIT NO. 3 - FACSIMILE TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION TO BE DISCUSSED IN AN UPCOMING CONFERENCE CALL (TAC NO.
The attached draft request for additional information (RAI) was transmitted by facsimile on January 26, 2006, to Mr. Paul Willoughby, at Dominion Nuclear Connecticut, Inc. (DNC).
This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call with DNC in order to clarify certain items in the licensees submittal. The draft RAI is related to DNCs submittal dated September 13, 2005, regarding a Technical Specification change in the recirculation spray system timing. Review of the draft RAI would allow DNC to determine and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not convey a formal request for information or represent an NRC staff position.
Docket No. 50-423
Enclosure:
As stated
January 26, 2006 MEMORANDUM TO: Darrell J. Roberts, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM:
Victor Nerses, Senior Project Manager /RA by G. Edward Miller for/
Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
MILLSTONE POWER STATION, UNIT NO. 3 - FACSIMILE TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION TO BE DISCUSSED IN AN UPCOMING CONFERENCE CALL (TAC NO.
The attached draft request for additional information (RAI) was transmitted by facsimile on January 26, 2006, to Mr. Paul Willoughby, at Dominion Nuclear Connecticut, Inc. (DNC).
This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call with DNC in order to clarify certain items in the licensees submittal. The draft RAI is related to DNCs submittal dated September 13, 2005, regarding a Technical Specification change in the recirculation spray system timing. Review of the draft RAI would allow DNC to determine and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not convey a formal request for information or represent an NRC staff position.
Docket No. 50-423
Enclosure:
As stated DISTRIBUTION:
Public ADrozd RidsNrrDraAadb LPL1-2 RidsNrrPMVNerses Accession No.: ML060250261 OFFICE LPL1-2/PM LPL1-2/LA ADB/C LPL1-2/BC NAME VNerses (GEMiller for)
CRaynor MKotzalas DRoberts DATE 1/25/06 1/25/06 1/11/06 1/26/06 OFFICIAL RECORD COPY
Enclosure REQUEST FOR ADDITIONAL INFORMATION MILLSTONE POWER STATION, UNIT NO. 3 (TAC NO. MC8327)
By letter dated September 13, 2005, Dominion Nuclear Connecticut, Inc. submitted a license amendment request for a change to the recirculation spray system timing in the Millstone Power Station, Unit No. 3, Technical Specifications. The Nuclear Regulatory Commission staff requests the following additional information to complete its review.
1.
What is the change in post loss-of-coolant accident sump water level resulting from the requested amendment?
2.
Please provide a comparison between containment pressure/temperature profiles on record and those resulting from the requested revised recirculation spray system (RSS) timing.
3.
Provide a copy of the revised input to LOCTIC code indicating relevant changes.
4.
Which method is used for, and what is the accuracy of, the refueling water storage tank (RWST) water level measurement?
5.
What is the reliability of the low-low RWST level signal as compared to the fixed clock signal? How does the requested revision affect the plants core damage frequency and large early release frequency?
6.
Since RSS (sump) water is contaminated with various impurities and removed fission products, its removal effectiveness may be affected (i.e., decreased).
(a)
Please elaborate on RSS removal mechanisms and/or justify calculated RSS removal rates for both aerosol and gaseous iodine.
(b)
Please justify using a 20-per-hour elemental iodine removal coefficient for RSS.
7.
Provide quench spray system (QSS) and RSS volumetric flow fluxes (cm3/cm2-sec, i.e., volumetric flow rate divided by projected spray surface area) for separate and combined operation.
8.
Provide the input deck for RADTRAD-NAI.
9.
It is not clear whether the credit for natural deposition is taken in the sprayed, unsprayed or both regions? If the natural deposition is applied only in the unsprayed region, is the removed aerosol deposited in the sprayed region? If so, that effect is already included in the 2-per-hour mixing rate. If the natural deposition is applied in the sprayed region, is it added to the spray removal rate? Please explain and justify the applied model.
10.
Please provide the reference and/or calculation for the spray removal rates, i.e., 12.37 per hour for QSS, 14.11 per hour for combined operation of QSS and RSS, and 7.77/0.78 per hour for RSS.