ML042730160
| ML042730160 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 10/13/2004 |
| From: | Tam P NRC/NRR/DLPM/LPD1 |
| To: | Crane C AmerGen Energy Co |
| References | |
| TAC MC1651 | |
| Download: ML042730160 (6) | |
Text
October 13, 2004 Mr. Christopher M. Crane President and Chief Nuclear Officer AmerGen Energy Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
OYSTER CREEK NUCLEAR GENERATING STATION - CORRECTION OF AMENDMENT NO. 247 RE: CORE SPRAY SYSTEM REQUIREMENTS (TAC NO. MC1651)
Dear Mr. Crane:
On August 19, 2004, the Nuclear Regulatory Commission staff (NRC) issued the subject amendment. The amendment clarified the Technical Specifications requirements for inoperable core spray system components.
Subsequent to the issuance, Mr. David Robillard of your staff pointed out a number of errors in the amendment package. These are addressed as follows:
(1) Page 3.4-1 of the TSs inadvertently missed a note that was introduced by Amendment No. 241. Enclosed please find a replacement page containing the missing note.
(2) Pages 2 and 4 of the safety evaluation (SE) contained inadvertent errors caused by re-wording of your submitted information into the SE. Enclosed please find revised Pages 2 and 4 of the SE.
These errors were all administrative, and their correction does not change the NRC staffs conclusion in the SE. We apologize if this caused you any inconvenience.
Sincerely,
/RA/
Peter S. Tam, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-219
Enclosures:
As stated cc w/encls: See next page
October 13, 2004 Mr. Christopher M. Crane President and Chief Nuclear Officer AmerGen Energy Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
OYSTER CREEK NUCLEAR GENERATING STATION - CORRECTION OF AMENDMENT NO. 247 RE: CORE SPRAY SYSTEM REQUIREMENTS (TAC NO. MC1651)
Dear Mr. Crane:
On August 19, 2004, the Nuclear Regulatory Commission staff (NRC) issued the subject amendment. The amendment clarified the Technical Specifications requirements for inoperable core spray system components.
Subsequent to the issuance, Mr. David Robillard of your staff pointed out a number of errors in the amendment package. These are addressed as follows:
(2) Page 3.4-1 of the TSs inadvertently missed a note that was introduced by Amendment No. 241. Enclosed please find a replacement page containing the missing note.
(2) Pages 2 and 4 of the safety evaluation (SE) contained inadvertent errors caused by re-wording of your submitted information into the SE. Enclosed please find revised Pages 2 and 4 of the SE.
These errors were all administrative, and their correction does not change the NRC staffs conclusion in the SE. We apologize if this caused you any inconvenience.
Sincerely,
/RA/
Peter S. Tam, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-219
Enclosures:
Revised pages cc w/encls: See next page DISTRIBUTION:
PUBLIC OGC PD1-1 R/F GHill (2) RLaufer WBeckner PTam SLittle ACRS PEselgroth, RI Accession Number: ML02730160 OFFICE PD1-1/PM PD1-1/LA PDI-1/SC NAME PTam SLittle RLaufer DATE 9/30/04 10/04/04 10/13/04 OFFICIAL RECORD COPY
3.0 TECHNICAL EVALUATION
The OCNGS CS system is a low pressure ECCS consisting of two independent loops each containing two main pumps, two booster pumps, two parallel isolation valves outside the _
drywell, two parallel check valves inside the drywell, a spray sparger, and associated piping, instrumentation and controls. Each CS subsystem transfers water from the suppression pool, or alternately, the condensate storage tank (CST) and fire protection system, to the core spray sparger. The CS system may be initiated either automatically or manually. Core spray initiates _
on "low-low" reactor water level. _
The water supply for the OCNGS CS system is held in the torus and is drawn through three strainers into a common header. The torus is a steel shell, located below and around the base of the drywell. The torus contains a suppression pool and an air space for the reduction of pressure (by condensation) and containment of reactor system coolant. There is a connection _
from the CST to the suction of each CS system main pump through locked closed manual valves. The CST, and parts of the condensate transfer system, serve as the alternate supply of water for the CS system. The condensate transfer supply line for the CS system pumps is routed above grade from the CST, into a trench toward the Turbine Building. In addition, either _
of the diesel fire pump is capable of providing water to the CS system. The fire protection _
system is connected to each of the two CS system loops. The purpose of this connection is to provide a backup supply of cooling water to the spargers during torus cleaning operations.
The licensee proposed changes to OCNGS Section 3.4.A, Section 3.4.A Bases, and Section 3.5.A.2. Section 3.4.A contains operability requirements for the CS System. Section 3.4.A Bases provides an explanation of the requirements in Section 3.4.A. Section 3.5.A.2 describes conditions that must be satisfied during maintenance and repair to the primary containment, including draining of the torus. The licensee proposed to make these changes in order to clarify requirements for inoperable components, to render inoperable CS component verification requirements consistent with each other, and to modify the location requirement of stored water during periods of CS system inoperability. Various editorial changes are included to accommodate the proposed changes.
The Nuclear Regulatory Commission (NRC) staffs evaluation of the proposed changes follows.
3.1 Proposed TS Changes 3.1.1 New Section 3.4.A.1 The licensee proposed to combine the requirements of the current Sections 3.4.A.1 and 3.4.A.2 into a new Section 3.4.A.1. The current Section 3.4.A.1 requires the CS system to be operable at all times with irradiated fuel in the reactor vessel, except for specified conditions. The current Section 3.4.A.2 maintains that the torus water volume must be at least 82000 ft3 in order for the CS system to be considered operable. The proposed change is editorial and does not affect the requirements for the CS system. Therefore, the NRC staff found the proposed change acceptable.
Corrected by letter of 10/13/04
The licensee also proposed to add a new Section 3.4.A.4.b.(3) with the wording These systems are verified to be OPERABLE on a weekly basis. This addition requires verification of systems operability; such requirement did not exist in the current TSs. Therefore, the NRC staff found this change acceptable.
The current Section 3.4.A.10.d (being relocated to the new Section 3.4.A.4.d) requires at least one CS pump and components of the CS system necessary to deliver rated flow to the reactor vessel to be operable when the CS system is not required to be operable. The licensee proposed to maintain these requirements in the new Section 3.4.A.4.d and to add Verify the pump and components are OPERABLE, as described, on a weekly basis. This statement adds a previously non-existent requirement to verify component operability. The NRC staff found this addition acceptable.
The current Section 3.4.A.10.e.(1) (being relocated to Section 3.4.A.4.e.(1)) requires that no work shall be performed on the reactor or its connected systems that could lower reactor water level to less than 4' 8" above the top of active fuel. The level in the CST must be greater than 360,000 gallons of water. The required level in the CST is based on establishing a sufficient water source for the CS pumps in the event of a leak from the reactor vessel while insufficient water is available in the torus. Draining of the torus for cleaning is one example of when the torus could have insufficient water. The licensee proposed to modify this water volume requirement to ensure there is a minimum of 360,000 gallons of water available between the torus and condensate storage water tank inventories. The licensee stated that maintaining 360,000 gallons solely in the CST complicates outage scheduling and water transfer operations. If the torus is fully drained or partially drained, the pump suction for the CS pumps can be transferred to the CST through a manually operated valve. The level in the CST _
assures that enough water will be transferred to the torus to provide adequate net positive suction head (NPSH) for the CS pumps to deliver water to the reactor vessel. If the torus is partially filled, the water already in the torus can be used to reduce the amount needed from the CST. This inventory distribution, totaling at least 360,000 gallons between the CST and the torus, will continue to assure that sufficient NPSH for the CS pumps is available. To support this argument, the licensee performed a control rod drive (CRD) drop accident analysis.
Leakage from the vessel was evaluated based on dropping a CRD from the bottom of the vessel with no credit for seating of the control rod blade. The calculation assumed that the torus was completely drained and a CRD was dropped during maintenance. During the postulated CRD drop accident scenario, reactor water will leak from the reactor vessel bottom to the drywell and then to the torus through downcomer pipes. The licensees calculation evaluated the water level requirement and the time to reach 4' 8" above top of fuel from specified levels. The calculation showed that 360,000 gallons of water distributed between the CST and torus will provide adequate NPSH for the CS pumps to carry out their design function.
It also showed that sufficient time is available for an operator to manually open the suction valve to the CST in the event of a drain down event. The NRC staff reviewed the licensees reasoning and found the proposed change acceptable.
The current Section 3.4.A.10.e.(1) requires at least two redundant systems including core spray pumps and system components must remain operable.... The licensee proposed to revise this to say at least two redundant core spray systems including core spray pumps and system components must remain operable.... This revision adds more clarity. The licensee also proposed two additional requirements to this specification. The first new requirement reads [a]t least one recirculation loop discharge valve and its associated suction valve shall be Corrected by letter of 10/13/04
Oyster Creek Nuclear Generating Station cc:
Chief Operating Officer H. J. Miller AmerGen Energy Company, LLC Regional Administrator, Region I 4300 Winfield Road U.S. Nuclear Regulatory Commission Warrenville, IL 60555 475 Allendale Road King of Prussia, PA 19406-1415 Senior Vice President - Nuclear Services AmerGen Energy Company, LLC Mayor of Lacey Township 4300 Winfield Road 818 West Lacey Road Warrenville, IL 60555 Forked River, NJ 08731 Site Vice President - Oyster Creek Senior Resident Inspector Generating Station U.S. Nuclear Regulatory Commission AmerGen Energy Company, LLC P.O. Box 445 P.O. Box 388 Forked River, NJ 08731 Forked River, NJ 08731 Director - Licensing and Regulatory Affairs Vice President - Mid-Atlantic AmerGen Energy Company, LLC Operations 200 Exelon Way, KSA 3-E AmerGen Energy Company, LLC Kennett Square, PA 19348 200 Exelon Way, KSA 3-N Kennett Square, PA 19348 Manager Licensing - Oyster Creek Exelon Generation Company, LLC John E. Matthews, Esquire 200 Exelon Way, KSA 3-E Morgan, Lewis, & Bockius LLP Kennett Square, PA 19348 1111 Pennsylvania Avenue, NW Washington, DC 20004 Oyster Creek Generating Station Plant Manager Kent Tosch, Chief AmerGen Energy Company, LLC New Jersey Department of P.O. Box 388 Environmental Protection Forked River, NJ 08731 Bureau of Nuclear Engineering CN 415 Regulatory Assurance Manager Trenton, NJ 08625 Oyster Creek AmerGen Energy Company, LLC Vice President - Licensing and P.O. Box 388 Regulatory Affairs Forked River, NJ 08731 AmerGen Energy Company, LLC 4300 Winfield Road Warrenville, IL 60555 Vice President - Operations Support AmerGen Energy Company, LLC 4300 Winfield Road Warrenville, IL 60555
Oyster Creek Nuclear Generating Station cc:
Vice President, General Counsel and Secretary AmerGen Energy Company, LLC 2301 Market Street, S23-1 Philadelphia, PA 19101 Pete Eselgroth, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406-1415 Correspondence Control Desk AmerGen Energy Company, LLC P.O. Box 160 Kennett Square, PA 19348