ML19320C036
| ML19320C036 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 07/11/1980 |
| From: | Sylvia B VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 601, IEB-80-06, IEB-80-6, NUDOCS 8007150671 | |
| Download: ML19320C036 (5) | |
Text
VIROINIA ELECTRIC AND POWER C OMPANY Rrenwown,VxmorwzA 20261 July 11, 1980 Mr. James P. O'Reilly, Director Serial No. 601 Office of Inspection and Enforcement N0/RGS:smv U. S. Nuclear Regulatory Commission Docket No. 50-339 Region II License No. NPF-7 101 Marietta Street, Suite 3100 Atlanta, Georg~
30303 i
Dear Mr. O'Re.*'
IE BULLETIN 80-06 NORTH ANNA POWER STATION UNIT NOS. 1 AND 2 This letter is in response to a telephone conversation held with NRC repre-sentatives on June 30, 1980.
It appears that several commitments in our IE Bulletin 80-06 response letter, Serial No. 421, are in conflict with commit-ments made in earlier letters of April 15, 1980, Serial No. 246 and June 10, 1980 letter, Serial No. 463.
NRC Comment It was noted that Vepco committed in the April 15, 1980, letter to pro-j vide a full evaluation and answers to the following concerns in Vepco's response to IE Bulletin 80-06.
"1) The overriding of one type of safety actuation signal (e.g.,
particulate radiation) should not cause the blocking of any other type of safety actuation signal (e.g., iodine radiation, reactor pressure) for those valves that have no function other thar containment isolation.
- 2) Physical features -(e.g., key lock switches) should be provided to ensure adequate administrative controls.
- 3) A system level annunciation of the overridden status should be provided for every safety system impacted when any override is active.
(See Regulatory Guide 1.47)."
(From NRC letter, PCTENTIAL DESIGN-DEFICIENCIES IN BYPASS, OVERRIDE, AND RESET CIRCUITS OF ENGINEERED SAFETY FEATURES dated March 13, 1980)
The response to the Bulletin did not contain the requested information.
8007150fp
VinoixA ELECTkIC AND Powzk COMPAW TO Mr. James P. O'Reilly, Director Response We have reviewed our protection system design to determine its degree of conformance to the Items 1, 2 and 3 criteria defined in the NRC letter dated March 13, 1980, on Bypass, Override and Reset circuits.
The following is our response to the NRC concerns:
Item 1.
The-overriding of one type of safety actuation signal of Engineered Safety Features circuits does not cause the blocking of any other type of safety actuation signal.
Items 2., 3.
The physical features provided for administrative controls and system level annunciation of override status for North Anna Unit 2 are provided in the following table:
ESF Admin.
Service Signal Bypass / Override Control Annunciation 1.
Quench Spray PP CDA Limit Switch -
None None Suction VV -
Will complete MOV-QS200A close sequence MOV-QS200B before opening on CDA.
If push-button is held in "close" valve opening is prevented.
2.
Quench Spray PP CDA Limit Swi tch -
None None Disch VV -
Will complate MOV-QS201A close sequence MOV-QS201B before opening on CDA.
If push-button is held in "close", valve opening is prevented.
3.
Recirculation CDA Key Switch Yes
- 624 Spray Heat Annunciator Exch. Supply Window VV-M0tt-SW203A MOV-SW203B MOV-SW203C MOV-SW203D
i v:NOINIA Ex.zcTm:C AND Powrk COMPANY TO MF,. James P. O'Reilly, Director ESF Admin.
Service Signal Bypass / Override Control Annunciation 4.
Rec'rculation CDA Key Switch Yes
- 624 Spray Heat Annunciator Exch. Return Window VV-MOV-SW204A MOV-SW204B MOV-SW204C MOV-SW204D 5.
Recirculation CDA Selector Switch None None Spray PP Case If selector Cooling PP switch is placed 2-RS-P-3A in "0FF" position 2-RS-P-3B to defeat CDA, selector must be held in "0FF" position (spring return to normal) 6.
Boric Acid SI Pusbutton - The None None Isolation VV pushbutton must 2884A be held.n "0 PEN" 2884B position to defeat 2884C the closure of the VV 7.
Emergency SI Selector Switch -
Yes
- 256 Generator 2H -
Selector switch Annunciator Start circuit 1 placed in normal Window Start circuit 2 position transfers to manual local.
8.
Emergency S1 Selector Switch -
Yes
- 256
-Generator 2J -
Selector switch Annunciator Start circuit 1 placed in normal Window Start circuit 2 position transfers to maaual local.
1.
We have determined that 4160 volt and 480 volt switchgear can be disabled by operation of an operating switch in the
" Pull to Lock" position.
This could defeat an ESF signal to close, however, it is considered under administrative control and is annunciated.
2.
Operation of certain electrical protection relays can ovenide an ESF signal to start 4 KV equipment for bus protection.
This is automatic protection.ind is annun-4 ciated and is documentet in our FSAR.
I Vinotwaa Ei.zernic amp Powna Cowrawv TJ Kr. James P. O'Reilly, Director '
NRC Comment In a June 10, 1980, letter from Vepco, it was indicated that the Service Water Radiation Monitoring Sample Pumps for Unit 2 had been modified so that once the CDA or SI is received, the pumps will continue operating through the timing sequence. However, in the IE Bulletin 80-06 response, Vepco indicated that the modification would not be made until the first refueling outage.
Have the Service Water Radiation Monitoring Sample Pumps control circuits been modified?
Response
The Service Water Radiation Monitoring Sample Pumps circuit modifi-cation for Unit 2 has been completed.
NRC Comment Vepco indicated in the June 10, 1980, response that the Main Conlenser Air Ejector to containment modification would be accomplished by January 1, 1981, for Unit 2.
This commitment is in conflict with the Bulletin re-sponse which committed to the implementation of the circuit modification by the next refueling outage. When will the modification be completed?
Response
The Main Condenser Air Ejector to containment circuit modification will be accomplished before full power operation of Unit 2.
NRC Comment In discussions with NRC staff members, it has been determined that Vepco's commitment to the January 1,1981, implementation of the Main Steam Trip Valve modification is unacceptable.
The NRC requires that the control circuit modification be implemented prior to full power operation.
Response
l The Main Steam Trip Valve control circuit modification will be imple-mented prior to the full power operation of Unit 2.
NRC Comment The NRC request.:d that Vepco verify that the Engineered Safety Feature (ESF) reset controls for Unit 2 were tested during the preoperational test program to determine the applicability of the reset problem dis-covered on Unit 1.
J l
l
vinosNIA Etrcra:C AND POWEa COMPANY TO Mr. James P. O'Reilly, Director Response During the preoperac.ional phase of Unit 2, the ESF reset problem was discovered on Unit 1.
Unit 2 was reviewed to determine the applicability of the problem.
Appropriate modifications were made and tested on Unit 2.
Other corrective actions are scheduled and, in the interim, administrative controls are in place.
Applicable w ests are conducted periodically on the ESF reset circuits to verify operability at required surveillance intervals.
I.*
you have any questions or require additional informt ion, please contact this office.
Very truly yours,
~
lll'
- ~
, / \\ v, p; B. R." Sylvia Manager - Nuclear Operations and Maintenance RGS/smv:SQ3 cc:
Mr. Robert A. Clark, Chief NRC Office of Nuclear Reactor Regulation Operating Reactors Branch No. 3 Division of Licensing Washington, D. C.
20555 Mr. B. Joe Youngblood, Chief NRC Office of Nuclear Reactor Regulation Licensing Branch 1 Division of Licensing Washington, D. C.
20555 i