RA-14-035, Submittal of Changes to Technical Specifications Bases

Submittal of Changes to Technical Specifications Bases

ML14111A343
Person / Time
Site:	Oyster Creek
Issue date:	04/10/2014
From:	Jim Barstow Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RA-14-035
Download: ML14111A343 (4)

Text

200 Exelon Way AdNow AdENOW Kennett Square, PA 19348 ExeLon Generation www.exeloncorp.com TS 6.21 .d RA- 14-035 April 10, 2014 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Oyster Creek Nuclear Generating Station Renewed Facility Operating License No. DPR-16 Docket No. 50-219

Subject:

Submittal of Changes to Technical Specifications Bases In accordance with the requirement of Oyster Creek Nuclear Generating Station Technical Specification 6.21 .d, Exelon Generation Company, LLC, is required to submit changes to the Technical Specifications Bases. Attached are two Bases changes since the last update.

If you have any questions or require further information, please contact Tom Loomis (610-765-5510).

Sincerely, James Barstow Director - Licensing & Regulatory Affairs Exelon Generation Company, LLC

Attachment:

Bases Pages 3.13-4 and 4.5-15 cc: USNRC Administrator, Region I USNRC Senior Resident Inspector, Oyster Creek USNRC Senior Project Manager, Oyster Creek Aooib

Attachment Bases Pages 3.13-4 and 4.5-15

As the safety valves present distinctly different concerns than those related to relief valves, the technical specifications are separated as to the actions taken upon inoperability. Clearly, the actuation of a safety valve will be immediately detectable by observed increase in drywell pressure. Further confirmation can be gained by observing reactor pressure and water level.

Operator action in response to these symptoms would be taken regardless of the acoustic monitoring system status. Acoustic monitors act only to confirm the reseating of the safety valve.

In actuality, the operator actions in response to the lifting of a safety valve will not change whether or not the safety valve reseats. Therefore, the actions taken for inoperable acoustic monitors on safety valves are significantly less stringent than that taken for those monitors associated with relief valves.

Should an acoustic monitor on a safety valve become inoperable, the setpoint on an adjacent monitor, if operable, will be reduced to assure alarm actuation should the safety valve lift. When a reduced setpoint results in having the acoustic monitor on an adjacent valve in an alarm condition due to background noise, the setpoint may be returned to normal. This will ensure that the adjacent valve's acoustic monitor remains operable. Analyses, using very conservative blowdown forces and attenuation factors, show that reducing the alarm setpoint on adjacent monitors to less than 1.4g will assure alarm actuation should the adjacent safety valve lift.

Minimum blowdown force considered was 30g with a maximum attenuation of 27dB. In actuality, a safety valve lift would result in considerably larger blowdown force. The maximum attenuation of 27dB was determined based on actual testing of a similar monitoring system installed in a similar configuration.

The operability of the accident monitoring instrumentation ensures that sufficient information is available on selected plant parameters to monitor and assess these variables during and following an accident. The capability is consistent with NUREGs 0578 and 0737.

The capability is provided to detect and measure concentrations of noble gas fission products in (1) plant gaseous effluents and (2) in containment during and following an accident. For the plant gaseous effluent capability, two Radioactive Gaseous Effluent Monitoring Systems (RAGEMS) are installed at Oyster Creek. One system monitors releases at the main stack (RAGEMS I) and the other monitors the turbine building vents (RAGEMS II). For the in containment post-accident capability, two high range radiation monitors are installed in the drywell. These monitors augment the capabilities provided by the Offsite Dosimetry Program.

I* OYSTER CREEK 3.13-4 Amendment No.: 64,57,94,116,137,157,168,237, ECR OC 13-00273

The operability of the instrument line flow check valves are demonstrated to assure isolation capability for excess flow and to assure the operability of the instrument sensor when required.

The representative sample consists of an approximately equal number of EFCV's such that each EFCV is tested at least every 10 years (nominal). In addition, the EFCVs in the sample are representative of the various plant configurations, models, sizes and operating environments.

This ensures that any potential common problem with a specific type or application of EFCV is detected at the earliest possible time. The nominal 10 year interval is based on other performance-based testing programs, such as Inservice Testing (snubbers) and Option B to 10 CFR 50, Appendix J. EFCV test failures will be evaluated to determine if additional testing in that test interval is warranted to ensure overall reliability is maintained. Operating experience has demonstrated that these components are highly reliable and that failures to isolate are very infrequent. Therefore, testing of a representative sample was concluded to be acceptable from a reliability standpoint.(g)

Because of the large volume and thermal capacity of the suppression pool, the volume and temperature normally changes very slowly and monitoring these parameters periodically is sufficient to establish any temperature trends. By requiring the suppression pool temperature to be continually monitored and also observed during periods of significant heat addition, the temperature trends will be closely followed so that appropriate action can be taken. The requirement for an external visual examination following any event where potentially high loadings could occur provides assurance that no significant damage was encountered. Particular attention should be focused on structural discontinuities in the vicinity of the relief valve discharge since these are expected to be the points of highest stress.

References (1) Licensing Application, Amendment 32, Question 3 (2) FDSAR, Volume I, Section V-1.1 (3) GE-NE 770-07-1090, "Oyster Creek LOCA Drywell Pressure Response," February 1991 (4) Deleted (5) FDSAR, Volume I, Sections V-1.5 and V-1.6 (6) FDSAR, Volume I, Sections V-1.6 and XIII-3.4 (7) FDSAR, Volume I, Section XIII-2 (8) Licensing Application, Amendment 11, Question 111-18 (9) GE BWROG B21-00658-01, "Excess Flow Check Valve Testing Relaxation," dated November 1998 OYSTER CREEK 4.5-15 Amendment No.: 4 65,4 86,216,210, 2,76 CoFrroo bylotto1 r 3/18N/W02 ECR OC 11-00473