ML20206H229
| ML20206H229 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 05/07/1999 |
| From: | Long W NRC (Affiliation Not Assigned) |
| To: | Campbell G CENTERIOR ENERGY |
| References | |
| TAC-MA1668, NUDOCS 9905110098 | |
| Download: ML20206H229 (5) | |
Text
1 M*h q k
UNITED STATES gj g
j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. - aaat 49*****
May 7, 1999 Mr. Guy G. Campbell Vice President - Nuclear FirstEnergy Nuclear Operating Company 5501 North State Route 2 Oak Harbor, OH 43449-9760
SUBJECT:
CHANGE TO TECHNICAL SPECIFICATION BASES - FACILITY OPERATING LICENSE NO. NPF DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO.1 (TAC NO. MA1668)
Dear Mr. Campbell:
By letter dated April 24,1998, you submitted a proposed change to the Davis Besse Nuclear Power Station, Unit No.1, Technical Specification (TS) Bases Section 2.2.1, " Limiting Safety System Settings - Reactor Protection System Instrumentation Setpoints - RC Pressure - Low, High, and Pressure Temperature."
TS basis page B 2-6 includes the following sentence:
The RC high pressure trip is backed up by the pressurizer code safety valves for RCS over pressure protection, and is therefore set lower than the set pressure for these valves, s 2525 psig.
You are proposing to change this text to read:
The RC high pressure trip is backed up by the pressurizer code safety valves for RCS over pressure protection. The RC high pressure trip is, therefore, set lower than the set pressure for these valves,2500 psig (nominal), even when accounting for the RPS RC pressure instrument string uncertaiaty.
The revised text refers to the nominal set pressure for the pressurizer code safety valves and adds clarifying information regarding instrument string uncertainty. This is an administrative
= change consistent with the Davis-Besse Technical Specifications, and is therefore acceptable.
Please replace the current TS bases page B 2-6 with the enclosed new TS bases page. The revised page contains a vertical line indicating the area of change. The marked up TS bases page attached to your letter did not accurately show the deletions and insertions on this page.
As discussed with your staff on May 15,1998, those errors have been corrected on the
- enclosed TS bases page.
9905110098 9903o7 DR ADOCK 05000346 p
n -.-
G. Campbell May 7, 1999 Please contact me if you have any questions regarding this matter. I can be reached at (301) 415-3026.
Sincerely, Original signed by:
I William O. Long, Sr. Project Manager, Section 2 Project Directorate ill Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-346
Enclosure:
As stated cc w/ encl: See next page Distnbution w/ encl:
Docket File GHill(2)
PUBLIC WBeckner PD32 r/f ACRS JAZ
-OGC GGrant, Rlll CThomas/AMendiola TCollins DOCUMENT NAME: G:\\DAVISBES\\DBA1668.LTR
- See Previous Concurrence v...~...w...
-m.m
...am. w c co.voimoo..+.....
r-co.--im.,,ci
... r OFFICE LA:LP03 l F PM LPD3 l
SRXB-BC 5C:1E03s9 %
NAME Eternhill W WLang TColline*
Amen 8To'le 'F W DATE J/ 7/99 5 / 7799 09/08/96 E G /99 OFFICIAL RECORD COPY g ggp gpWFRIM
\\
- 10033 foi g
r i
G. Campbell
- Please contact me if you have any questions regarding this matter. I can be reached at (301) 415-3026.
Sincerely, b.
William O. Long, Sr. Project Manager, Section 2 Project Directorate lll Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-346
Enclosure:
As stated cc w/ encl: See next page 1
1 3
i i
1 i
.-.._. _ _ ___... _ _ _.....~
Mr. Eliot Protsch Duane Amold Energy Center IES Utilities Inc.-
cc:
Jack Newman, Esquire Al Gutterman, Esquire Morgan, Lewis, & Bockius 1800 M Street, NW.
Washington, DC 20036-5869 Chairman, Linn County Board of Supervisors Cedar Rapids, IA 52406-IES Utilities Inc.
ATTN: Gary Van Middlesworth Plant Superintendent, Nuclear 3277 DAEC Road Palo,IA 52324 John F. Franz, Jr.
Vice President, Nuclear Duane Arnold Energy Center 3277 DAEC Road Palo,IA 52324 Ken Peveler Manager of Regulatory Performance Duane Amold Energy Center 3277 DAEC Road Palo,IA 52324 U.S. Nuclear Regulatory Commission Resident inspector's Office Rural Route #1 Palo,IA 52324 Regional Administrator, Rlil U.S. Nuclear Regulatory Commission 801 Warrenville Road -
Lisle,IL 60532-4531 Parween Baig Utilities Division lows Department of Commerce Lucas Office Building,5th floor Des Moines,IA 50319
--n-ns es___
,,em.--
-,w.-.
LIMITING SAFETY SYSTEM SETTINGS E'ASES The AXIAL POWER IMBALANCE boundaries are established in order to prevent reactor thermal limits from being exceeded. These thermal limits are either power peaking kW/ft limits or DNBR limits. The AXIAL POWER IMBALANCE reduces the power level trip produced by a flux-to-flow ratio such that the boundaries of the figure in the CORE OPERATING LIMITS REPORT are produced.
RC Pressure - Low. Hich. and Pressure Temnerature The high and low trips are provided to limit the pressure range in which reactor operation is permitted.
During a slow reactivity insertion startup accident from low power or a slow reactivity insertion from high power, the RC high pressure setpoint is reached before the high flux setpoint. The Allowable Value for RC high pressure, 2355 psig, has been established to maintain the system pressure below the safety limit, 2750 psig, for any design transient. The RC high pressure trip is backed up by the pressurizer code safety valves for RCS over pressure protection. The RC high pressure trip is, therefore, set lower than the set pressure for these valves, 2500 psig (nominal), even when accounting for the RPS RC pressure instrument string uncertainty. The RC high pressure trip also backs up the high flux trip.
The RC low pressure,1900.0 psig, and RC pressure-temperature (16.00 T 7957.5) psig, Allowable Values have been established to maintain the DEN ratio greater than or equal to the minimum allowable DNB ratio for those design accidents that result in a pressure reduction.
It also prevents reactor
- operation at pressures below the valid range of DNB correlation limits, protecting against DNB.
Hioh Flux / Number of Reactor Coolant Pumos On In conjunction with the flux - Aflux/ flow trip the high flux / number of reactor coolant pumps on trip prevents the :'iinimum core DNBR from decreasing below the minimum allowable DNB ratio by tripping the reactor due to the loss of reactor coolant pump (s).
The pump monitors also restrict the power level for the number of pumps in operation.
DAVIS-BESSE, UNIT I B 2-6 Amendment No. 33,45,50,51,100,100,218 Revised by NRC letter dated May 7, 1999 C
m.a.e n.-suc 4
,r--wm,ise,ua.yu,..,.eee.,
. _ pan.nse e.,
se, p
e4 wi