ML18116A308
| ML18116A308 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 08/08/1979 |
| From: | Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | Schwncer A Office of Nuclear Reactor Regulation |
| References | |
| 634, NUDOCS 7908130465 | |
| Download: ML18116A308 (7) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY RIC:0:MON.l>, VrRGXN IA 23261 August 8, 1979 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation Attn:
Mr. A. Schwencer, Chief Operating Reactors Branch No. 1 Division of Operating Reactors U. S. Nuclear Regulatory Commission Washington, DC 20555
Dear Mr. Denton:
Serial No. 634 LQA/DWSj r:j ab Docket Nos.
50-280 50-281 License Nos.
DPR-32 DPR-37 AMENDMENT OF OPERATING LICENSES SURRY POWER STATION UNIT NOS. 1 AND 2 PROPOSED TECHNICAL SPECIFICATION CHANGE NO. 79 Pursuant to 10 CFR 50.90, the Virginia Electric and Power Company hereby requests an amendment, in the form of changes to the Technical Specifications, to Operating Licenses DPR-32 and DPR-37 for the Surry Power Station, Unit Nos. 1 and 2.
The proposed changes are enclosed and have been designated as Change No. 79.
IE Bulletin 79-06A, item 13 requires the Licensee to no longer depend on Pressurizer level for safety injection actuation coincident with low pressurizer pressure.
As a result, actuation from only low pressurizer pressure using a (2/3) logic is proposed.
Dependence on (2/3) low pressurizer pressures to actuate safety injection is conser-vative and consistent with other protective functions.
(2/3) logic will also give increased reliability and testability needed for long term operation.
The coincidence arrangement of pressurizer pressure and level was originally designed to prevent false actuations of the SI system in the event of spurious pressurizer pressure or level signals.
Removal of the level signal will eliminate all dependency on level for SI protection.
Therefore, whenever system pressure is below 1700 psig, SI will be initiated regardless of the water volume present.
This is a conservative way of insuring the core receives cooling.
Issuance of these specifications by NRC should allow for installation and procedural changes.
Therefore, the license should indicate the speci-fication to be effective following installation at the earliest cold shut-down condition.
The enclosed changes have been reviewed and approved by the Station Nuclear Safety and Operating Committee and the System Nuclear Safety;;; lt!la ee'
/fJ(Jt,,~
'11A-0 S
-'t~Hlli1!iO'f6:
e VIRGINIA ELECTRIC AND POWER COMPANY TO Mr. Harold R. Denton 2
Operating CoTIIlllittee.
It has been detennined that this request does not involve an unreviewed safety question.
We have evaluated this request in accordance with the criteria specified in 10 CFR 170.22.
The staff should be able to determine that this request does not involve a significant hazards consideration.
Accord-ingly, this request has been determined to be Class III for Unit 1.
The duplicate revision for Unit 2 has been designated Class I.
A check in the amount of $4,400.00 is attached in payment of the amendment fees.
Very truly yours, zii. )2/). 01 at?~;':-,, tJ/
C. M. Stallings Vice President-Power Supply and Production Operations At ta chm en ts:
(1)
Change No. 79 (2)
Check in amount of $4,400.00 cc:
Mr. James P. O'Reilly, Director Office of Inspection and Enforcement Region II
COMMONWEALTH OF VIRGINIA CITY OF RICHMOND
)
) s. s.
)
Before me, a Notary Public, in and for the City and Common-wealth af6resaid~ today personally appeared C~ M. Stallings, who being duly sworn, made oath and said (1) that he is Vice President-Power Supply and Production Operations, of the Virginia Electric and Power Company, (2) that he is duly authorized to execute and file the fore-going Amendment in behalf of that Company, and (3) that the statements in the Amendment are true to the best of his knowledge and belief.
Given under my hand and notarial seal this filh.. day of
- A ~,1~t
, l1Z!L*
My Commission expires (SEAL)
\\l' L
TS 3. 7-4 to generator signals acttJ.ating the SIS active phase.
The SIS active phase is also actuated by a high containment pressure signal brought about by loss-,
of high enthalpy coolant to the containment *. This actuation signal acts as a backup to the low pressurizer pressure actuation of the SIS and diversity to protection against loss of coolant.
- _l adds Signals are also provided to actuate the SIS upon sensing the effects of a steam line break accident. Theyefore, SIS actuation following a steam line break is designed to occur upon sensing hi.gh d.iffert!ni..ial steam* pressure between the steam header and steam generator line or upon sensing high steam line flow in coincidence with low reactor coolant average temperature or low steam line pressure.
The increase in the extraction of RCS heat following a steam line break results in reactor coolant temperature and pressure reduction. For this reason protection against a steam line break accident is also provided by low pres-surizer pressure actuating safety injection.
Protection is also provided for a steam line break in the'containment by actuation of SIS upon sensing high containment pressure.
SIS actuation injects highly borated fluid into the Reactor Coolant System in order to counter the reactivity insertion brought about by cooldown of the reactor coolant which occurs during a steam line break accident.
\\
\\
TS 3. 7-6 in order to prevent excessive cooldown of the reactor coolant system. This mitigates the effect of an accident such as steam break which in itself causes excessive coolant temperature cooldown.
Feedwater line isolation also reduces the consequences of a steam line break inside the contairunent, by stopping the entry of feedwater.
Setting Limits
- 1.
The high containment pressure limit is set at about 10% of design
- containment pressure. Initiation of Safety Injection protects against 1
f 1
( 2) l' b
k (3 )
"d
- d.
d.
- h.
ass o coo ant or steam ine rea*
acci ents as iscusse int e safety analysis.
- 2.
The high-high containment pressure limit is set at about 50% of design containment pressure. Initiation of Containment Spray and Stea~ Line Isolation protects a3ainsl large loss of c0olant (Z) or steam line bre.<1k accidents (3 ) as discussed in the safety analysis.
- 3.
The pressurizer low pressure setpoint for safety injection actuation is set substantially below system operating pressure limits. However, it is sufficiently high to protect against a loss-of-coolant accident as shown h
f 1
( 2) int e sa ety ana ysis.
- 4.
The steam line high differential pressure limit is set well below I
- a.
- b.
C,
<l.
- e.
- n.
FUNCTIONAL UNIT 1 SAFETY INJECTION 2
Manual High Containment Pressure (Hi Setpoint)
High Differential Pressure be tween nny S.team Line and the Steam Line Header Pressurizer Low Low ::Pressure High Steam Flow* in 2/3 Steam Lines with Low T or Low Steam Line Pres~~~e CONTAINMENT SPRAY Manual b,
11igh Containment Pressure (Hi Hi Setpoint)
TABLE 3. 7-2 ENGINEERED S./\\FEGU/1.RDS ACTION 1
MIN.
OPERABLE CHANNELS 1
3 2/non-isolated loop 2
1/ s temnline 2 T avg signals 2 Steam Pres-sure Signals 2
3 2
MIN.
DEGREE OF REDUN-DANCY 0
1 1/non-isolated loop l
1 1
l' 3
PE~~ISSIBLE BYPASS CONDITIONS Primary Pressure*
less than 2000 psig except when reactor is critical 4
OPER/\\TOR ACTION IF CONDITIONS OF COLUMN l OR 2 EXCEPT AS CONDI-TJ.ONED BY COLUMN CANNOT BE HET Cold Shutdown Cold Shutdown Cold Shutdown Cold Shutdown Reactor Coolant aver-Cold Shutdown age temperature less than 547°F during heatup and cooldown, Cold Shutdown Cold Shutdown
'Ide -
Must actuate 2 switches simultaneously H;~ -
IJith the spec~fied ~min~~um~ operable clrnnnd,c:; the 2/3 high stenr, flow is alread:,.7 111 the trip mode
(\\
3
~
r.n w
-..J I
f-..1 I-'
NO.
1 2
i 3 4
5
.'~
TABLE 3. 7-li ENGINEERED SAFETY FEATURE SYSTEM INITIATION LIMITS INSTRUHENT SETTING FUNCTIONAL UNIT High Containment Pressure (High Containment Pressure Signal)
High High Containment Press.ure * (High High Containment Pres3ure Signal)
Pressurizer Low Low Pressure High Differential Pressure Between Steam Line and the Steam Line Header High Steam Flow in 2/3 Steam Lines Coincident with Low Tavg or Low Steam Line Pressure CHANNEL ACTION a) Safety Injection b) Containment Vacuum Pump Trip c) High Pressure Containment Isolation d) Safety Injection Containment Isolation e) F.W. Line Isolation a) Containment Spray b) Recirculation Spray c) Steam Line Isolation d) High High Pressure Con-tainment Isolation a) Safety Injection b) Safety Injection Contain-ment Isolation cJ Feedwat~r Line Isolation a) Safety Injection b} Safety Injection Contain-ment Isolation c) F.W. Line Isolation a) Safety Injection b) Steam Line Isolation c) Safety Injection Contain-mcmt Isolation d) F.W. Line Isolation SETTING LIMIT 2_5 psig
<25 psig
~.1,700 psig
<150 psi
<40% (at zero load) of full steam flow
- .40% (at 20% load) of
. full steam flow
~110% (at full load) of full steam flow
?-541 op Tavg.
>500 psig steam line pressure t
H C/l
- w
-...J I
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