NL-03-019, Reply to Request for Additional Information Regarding Proposed License Amendment for Relaxation of Pressurizer Water Level Requirement
| ML030280083 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 01/23/2003 |
| From: | Dacimo F Entergy Nuclear Northeast |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-03-019 | |
| Download: ML030280083 (6) | |
Text
Entergy Entergy Nuclear Northeast Entergy Nuclear Operations, Inc.
Indian Point Energy Center 295 Broadway, Suite 1 RO Box 249 Buchanan, NY 10511-0249 January 23, 2003 NL-03-019 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Stop O-P1 -17 Washington, DC 20555-0001
SUBJECT:
Indian Point Nuclear Generating Unit No.3 Docket No. 50-286 Reply to Request for Additional Information Regarding Proposed License Amendment for Relaxation of Pressuizer Water Level Requirement
REFERENCE:
- 1. Entergy letter to NRC, IPN-02-043; "Proposed Changes to Technical Specifications for Pressurizer Water Level Requirement,"
dated May 30, 2002.
Dear Sir:
This letter provides additional information requested by the NRC regarding the license amendment request submitted by Entergy Nuclear Operations, Inc (ENO) in Reference 1. The additional information was requested by the NRC during a conference call with ENO personnel on October 10, 2002.
The requested information provided in Attachment I, is additional technical justification for the requested license amendment and does not alter the conclusions of the no significant hazards evaluation previously provided in Reference 1. Commitments identified in this response are documented in Attachment I1. If you have any questions or require additional information, please contact Mr. Kevin Kingsley at 914-734-5581.
1 declare under penalty of perjury that the foregoing is true and correct. Executed on V1 er y ty u rs, Fred Dacimo Site Vice President Indian Point Energy Center
/
cc: next page Attachments: as stated
NL-03-019 Docket No. 50-286 Page 2 of 2 cc:
Mr. Patrick D. Milano, Senior Project Manager Project Directorate I, Division of Reactor Projects 1/11 U.S. Nuclear Regulatory Commission Mail Stop 0 8 C2 Washington, DC 20555 Mr. Hubert J. Miller Regional Administrator Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Resident Inspector's Office Indian Point Unit 3 U.S. Nuclear Regulatory Commission P.O. Box 337 Buchanan, NY 10511 Mr. William M. Flynn New York State Energy, Research and Development Authority Corporate Plaza West 286 Washington Avenue Extension Albany, NY 12203-6399 Mr. Paul Eddy New York State Dept. of Public Service 3 Empire Plaza Albany, NY 12223
ATTACHMENT I TO NL-03-019 RESPONSE TO NRC QUESTION REGARDING PROPOSED LICENSE AMENDMENT REQUEST FOR RELAXATION OF PRESSURIZER WATER LEVEL REQUIREMENT ENTERGY NUCLEAR OPERATIONS, INC.
INDIAN POINT NUCLEAR GENERATING UNIT NO. 3 DOCKET NO. 50-286
Attachment I to NL-03-019 Docket 50-286 Page 1 of 2 The following question was provided by NRC during a conference call with ENO personnel on October 10, 2002.
Question:
Provide information to demonstrate that overfilling the pressurizer, with the plant operating at the proposed new pressurizer water level limit, is not credible for events such as inadvertent safety injection or a malfunction of the chemical and volume control system.
Response
The proposed change to the Indian Point 3 Technical Specifications will allow plant operation in Mode 3 with a pressurizer level limit of 90% actual (i.e., not including indicating instrument uncertainities). The purpose of this request is to provide additional flexibility during a plant cooldown when pressurizer level is dropping due to thermal contraction of the reactor coolant inventory.
At a pressurizer level of 90% (actual), there is approximately 2300 gallons of empty volume in the pressurizer. In the event that a charging pump is operating (98 gpm) without letdown, the operator would have more than 20 minutes to respond to the condition. In the unlikely event that all three charging pumps are operating without letdown, the operator would have nearly 8 minutes to respond to the condition. Since the purpose of the license amendment request is to support a specific and limited plant evolution (e.g., plant cooldown from Mode 3 to Mode 4),
ENO will implement administrative controls which will require that a dedicated operator be assigned for operating and controlling the chemical and volume control system, including monitoring pressurizer level, whenever pressurizer level in Mode 3 is above the existing Technical Specification limit of 58.3% (actual). This operational requirement will be stated in the Technical Specification Bases and implemented through the operating procedure for plant cooldown.
The effect of an inadvertent safety injection on pressurizer water level is limited because Indian Point 3 is designed with low head safety injection pumps. The pressure-temperature limits for operating the plant in Mode 3 are established, in part, by the operating curves which ensure that the reactor pressure boundary fracture toughness requirements of 10 CFR 50 Appendix G are satisfied. The nominal shutoff head of the safety injection pumps is 1500 psig, which is bounded by the Appendix G upper pressure limit curve. Therefore, in the event of a safety injection actuation in Mode 3 with pressure above the pump shutoff head, no mass injection would occur and pressurizer level would not be affected. In the event of a safety injection with pressure below the shutoff head, the resulting mass injection would compress the pressurizer steam space and system pressure would increase to the pump shutoff head, at which point additional mass injection and increase in pressurizer level would terminate. Using the
'enhanced pump' assumption, which uses a shutoff head of 1600 psig, there is a very narrow temperature range in Mode 3 (350 OF to approximately 352 0F) where the upper pressure limit for the Appendix G curve could be slightly exceeded. The overpressure is approximately 25 psig at 350 OF and drops to zero at approximately 352 OF. In addition, because the safety
Attachment I to NL-03-019 Docket 50-286 Page 2 of 2 injection pumps are centrifugal-type pumps, the flowrate drops as the backpressure increases, and this scenario is bounded by the maximum charging condition described above. The dedicated operator monitoring pressurizer level would therefore also be able to take appropriate action in this case.
References:
- 1. Indian Point 3 FSAR Section 9.2, "Chemical and Volume Control System."
- 2. Indian Point 3 Design Basis Document 306, "Safety Injection System."
- 3. Indian Point 3 Technical Specification Section 3.4.3, "RCS P/T Limits."
- 4. Indian Point 3 Calculation, IP3-CALC-RCS-02444, "Generation of All PTLR Curves."
Attachment II to NL-03-019 Docket 50-286 Page 1 of 1 COMMITMENT REGARDING PROPOSED LICENSE AMENDMENT REQUEST FOR RELAXATION OF PRESSURIZER LEVEL REQUIREMENT IN MODE 3 Number Commitment Due Date NL-03-019-01 Revise Technical Specification Bases to specify a On or before the requirement that a dedicated operator is assigned implementation for operating and controlling the chemical and date established volume control system, including monitoring when the License pressurizer level, whenever pressurizer level in amendment is Mode 3 is above the existing Technical issued.
Specification limit of 58.3%.
NL-03-019-02 Revise the operating procedure for plant cooldown Prior to use of the from Mode 3 to Mode 4 to implement the relaxed limit on requirement for a dedicated operator as stated in pressurizer water the revised Technical Specification Bases.
level in Mode 3.