ML20244E275
| ML20244E275 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 04/14/1989 |
| From: | Sieber J DUQUESNE LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 8904240391 | |
| Download: ML20244E275 (9) | |
Text
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ver Wiley Power Staten Shippmgport, PA 15040004
$00dIU"se. o,
m2mn2ss April 14, 1989 U.
S. Nuclear Regulatory Commission Attn:
Document Control Desk Washington, DC 20555
Reference:
Beaver Valley Power Station, Unit No. 1 and No. 2 BV-1 Docket No. 50-334, License No. DPR-66 BV-2 Docket No. 50-412, License No. NPF-73
. Response to Station Blackout Rule - 10CFR50.63 Gentlemen:
On July 21,
- 1988, the Nuclear Regulatory Commission (NRC) amended its regulations in 10 C.F.R.,
Part 50.
A new section, 50.63, was added which ' requires that each light-water-cooled nuclear power plant be able to withstand and recover from a station blackout (SBO) of a
specified duration.
Utilities are expected to have the baseline assumptions, analyses and related information used in their coping evaluation available for NRC review.
It also identifies the factors that must be considered in specifying the station blackout duration.
Section 50.63 requires
- that, for the ' station blackout duration, the plant be capable of maintaining core cooling and appropriate containment integrity.
Section 50.63 further requires that each licensee submit the following information:
1.
A proposed station blackout duration including a justification for the selection based on the redundancy and reliability of the onsite emergency AC power sources, the expected frequency of loss of offsite
- power, and the probable time needed to restore offsite power; 2.
A description of the procedures that will be implemented for station blackout events for the duration (as determined in 1 above) and for recovery therefrom; and 3.
A list and proposed schedule for any needed modifications to equipment and associated procedures necessary for the specified SBO duration.
60 0
8904240391 890414 ADOCK05000g34 i
DR
7 l
l Beaver Valley Power Station, Unit No. 1 and No. 2 BV-1 Docket No. 50-334, License No. DPR-66 BV-2 Docket No. 50-412, License No. NPF-73 Response to Station Blackout Rule-10CFR50.63 Page 2 The NRC has issued Regulatory Guide 1.155 " Station Blackout" which describes a
means acceptable to the NRC Staff for meeting the requirements of 10 C.F.R. 50.63.
Regulatory Guide (RG) 1.155 states that the NRC Staff has determined that NUMARC 87-00
" Guidelines and Technical Bases for NUMARC Initiatives Addressing Station Blackout At Light Water Reactors" also provides guidance that is similar to the RG 1.155 guidance and is acceptable to the NRC Staff for meeting these requirements.
Table 1
to RG 1.155 provides a cross-reference between RG 1.155 and NUMARC 87-00 and notes where the RG has precedence.
Duquesne Light Company has evaluated Beaver Valley Units No. 1 and No.
2 against the requirements of the SBO rule using guidance from NUMARC 87-00 except where RG 1.155 has precedence.
The results of this evaluation are detailed in the following attachment.
Applicable NUMARC 87-00 sections are shown in parenthesis within the attachment.
The modifications and associated procedure changes identified in Parts A, B and C of the attachment will be completed within two years after the notification provided by the Director, Office of Nuclear Reactor Regulation in accordance with 10 C.F.R.
- 50. 63 (c) (3).
Since our Alternate AC (AAC) power source will involve cross-tieing buses between Units 1 and 2, installation and testing will require two (2) refueling outages to fully implement the cross-tie capability.
Therefore, the schedule for completion may need to be extended, dependent on the NRC approval date and the scheduled refueling outage dates for both Unit 1 and 2.
Very truly yours, Lb f D.
Sieber lice President Nuclear Group cc:
Dr. T. Murley, Director of Office of NRR Mr. J.
Beall, Sr. Resident Inspector Mr. W. T. Russell, NRC Region I Administrator Mr.
P.
Tam, Sr. Project Manager Director, Safety Evaluation & Control (VEPCO)
w;;p,.7-------
i COMMONWEALTH OF PENNSYLVANIA)
)-
SS:
-COUNTY OF BEAVER
)
k I -
On this
!M day of
//
- 1989, before me, N'
- 2 MW, Notary Public in and for said a
commonwealth and County, personally appeared J. D. Sieber, who being duly
- sworn, deposed, and said that (1) he is Vice President of Duquesne
- Light, (2) he is duly authorized to execute and file the
- foregoing Submittal on behalf of.said Company, and (3) the statements set forth in the Submittal are.true and correct to the best of his q
-knowledge, information and belief.
/
W0 M/vLP NotarialSeal Sheila M. Fattore, Notary Pubic 1 tippingport Boro, Besver County My Commessn Erpnes Oct.23,1989 Member, Pennsylvania Associmien of NoWies s
3 y-
Attachmnnt BVPS Response to Station Blackout Rule Page 1 A.
Pronosed Station Blackout Duration NUMARC 87-00, Section 3
was used to determine a proposed SBO duration of four hours.
The following plant factors were identified in determining the proposed station blackout duration (applicable to both Beaver Valley Unit 1 and Unit 2):
1.
AC Power Design Characteristic Group is P2 based on:
a.
Expected frequency of grid-related LOOPS does not exceed once per 20 years (Section 3.2.1, Part 1A, p.3-3);
b.
Estimated frequency of LOOPS due to extremely severe weather places the plant in Extremely Severe Weather (ESW) Group 1 (Section 3.2.1, Part 1B, p. 3-4);
c.
Estimated frequency of LOOPS due to severe weather places the plant in Severe Weather (SW)
Group 2
(Section 3.2.1, Part 1C, p.
3-7);
d.
The offsite power system is in the I3 Group (Section 3.2.1, Part 1D, p. 3-10) ;
2.
The emergency AC power configuration group is C based on:
(Section 3.2.2, Part 2C, p. 3-13) a.
There are two emergency AC power supplies per unit not credited as alternate AC power sources (Section 3.2.2, Part 2A, p. 3-15);
b.
One emergency AC power supply per unit is necessary to operate safe shutdown equipment following a loss of offsite power (Section 3.2.2, Part 2B, p. 3-15).
3.
The target EDG reliability is 0.975.
A target EDG reliability of 0.975 was selected based on having an average EDG reliability for the last 100 demands greater than 0.95 for BVPS Unit 1 consistent with NUMARC 87-00, Section 3.2.4.
The actual reliability values over the last 100 valid start demands at BVPS Unit 1 are 99%
for EDG #1 and 100% for EDG #2.
BVPS Unit 2,
licensed in 1987, has 19 valid start demands on the
Attachmnnt BVPS Response to Station Blackout Rule i
Page 2 l
4.
An alternate AC (AAC) power source will be utilized at the Beaver Valley Power Station which meets the criteria specified in Appendix B to NUMARC 87-00.
The AAC source will be an emergency AC (EAC) power source from the l
non-blacked out unit (Unit 1 or Unit 2) which meets the assumptions in Section 2.3.1 of NUMARC 87-00.
l The AAC configuration is shown on Figure 1.
With this configuration, the blacked-out unit will be capable of energizing one emergency bus from either of the emergency buses of the opposite unit by cross-tieing the normal 4KV buses between units and cross-tieing the emergency buses at the non-blacked-out unit if necessary.
All breaker operations will require local operator action.
The AAC power source will be available within one hour of the onset of the station blackout event.
One Emergency Diesel Generator from either unit has sufficient capacity and capability to operate equipment and systems necessary for coping with a
station blackout for the required SBO duration of 4
hours.
An AC independent coping analysis was performed for the one hour required to bring the AAC power source on line.
B.
Procedure Description Plant procedures have been reviewed per the guidelines in NUMARC 87-00, Section 4, in the following areas:
1.
AC power restoration
- Duquesne Light Company procedures address the concerns of Section 4.2.2 of NUMARC 87-00 and gives the highest priority to restoring power at our nuclear units.
The following procedures were reviewed and no changes were identified:
EOP ECA-0.0 " Loss of All AC Power" EOP ECA-0.1 " Loss of All AC Power Recovery Without SI Required" EOP ECA-0.2 " Loss of All AC Power Recovery With SI Required" DLC System Operations and Telecommunications Procedure Section L " Restoration of Station Service Power to Beaver Valley Power Station" l
n i
Attachm nt l
BVPS Response to Station Blackout Rule i
i Page 3 l
2.
Severe Weather - Beaver Valley Unit 1/2 Abnormal Operating Procedures address the guidelines for tornados per section 4.2.3 of NUMARC 87-00.
Beaver Valley procedures do not address actions for hurricanes due to the very low probability of a hurricane in this region as discussed in I
our UFSAR (Section 2).
The following procedures were reviewed and no changes were identified.
1 AOP-1/2.75.2
" Acts of Nature - Tornado" 3.
Station Blackout Response Guidelines - necessary procedure changes required per NUMARC 87-00,.Section 4.2.1 and procedure changes required after accessing coping capability per NUMARC 87-00, Section 7,
have been identified.
These procedure changes associated with our Emergency Operating Procedures (EOPs) will be implemented within one
- year, with the exception of those procedures associated with establishing the AAC power source and the use of this power source in responding to a SBO event.
Procedures associated with establishing the AAC power source will be completed within 2
years after NRC acceptance and following implementation of the proposed modification of the plant for the AAC power source.
Since our AAC power source will involve cross-tieing buses between Units 1
and 2,
installation and testing will require two (2) refueling outagez.
Therefore, the schedule will be dependent on NRC approval date and our scheduled outages for Units 1 and 2.
C.
Proposed Modifications and Schedulo Modifications to the Beaver Valley Unit 1/2 electrical buses will be required to provide the proposed AAC power source.
These modifications include installation of breaker cubicles, breakers and additional cables to provide the capability to cross tie the emergency 4KV buses, and installation of breaker
- cubicles, breakers and cables to provide the capability to cross tie the normal 4KV buses between the units.
Procedure changes will be required to address load
- shedding, energization of the blacked-out unit's buses from the AAC power source and startup of equipment required to cope with the SBO event.
1
Attachment BVPS Response to Station Blackout Rule Page 4 The AAC source has the capacity and capability to power the equipment necessary to cope with a
SBO in accordance with NUMARC 87-00, Section 7
for the required coping duration determined in accordance with NUMARC 87-00, Section 3.2.5.
1.
Condensate Inventory For Decay Heat Removal (SectioD
- 7. 2.1).
It has been determined from Section 7.2.1 of NUMARC 87-00 that 110,886 gallons of water are required for decay heat removal for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and plant cooldown for each 'init.
The minimum permissible condensate storage i sa,,
level per technical specifications provides 140,000 gallons of water for Unit 1
and 127,000 gallons of water for Unit 2, both of which exceeds the required quantity for coping with a 4-hour station blackout.
No plant modifications or procedure changes are needed to utilize these water sources.
2.
Class 1E Batterv Capacity (Section 7.2.2)
The Class 1E batteries at both Unit 1 and unit 2 have been reviewed (pursuant to NUMARC 87-00, Section 7.2.2) and determined to have sufficient capacity to meet station blackout loads for one hour.
3.
Comoressed Air (Section 7.2.3)
Air-opern td valves relied upon to. cope with a station blackout for one hour can be operated manually.
Valves requiring manual operation for operation are identified in plant procedures.
4.
Effects of Loss of Ventilation (Section 7.2.4) a.
HVAC systems serving the following dominant areas of concern are not assumed to be available, and the steady-state ambient air temperatures have been calculated:
AREA TEMPERATURE Unit 1 AFW Pump Room 118' F Unit 2 AFW Pump Room 114' F Unit 2 Process Instrument Room 128' F Unit 1/2 River Water Pump Cubicles 138' F
l-c.
. ' ~
f L
Attcchmant BVPS Response to Station Blackout Rule
-Page 5 I
b.
Control Room l
Beaver Valley Units 1/2 have a
joint control room complex with separate HVAC system for each control L
room.
The control room air conditioning units will l
not be available after a
SBO, however, the control room complex will be cooled via. forced air heat removal from the control room supply and exhaust fans which will be powered from the AAC power source.
Since the AAC' power source is assumed to not be available for the first hour after a SBO event,.both control rooms were evaluated for a complete loss of ventilation during a
SBO.
Both control rooms were i
found not to exceed 120' F steady state temperature and-are therefore not a
dominant area of concern
[NUMARC.87-00, Section 2.7.1].
Reasonable assurance of the operability of station blackout response equipment in the above dominant areas of concern that exceeded existing environmental qualification limits have aeen assessed using Appendix F.to NUMARC 87-00 and/or the Topical Report.
No modifications are required to' provide reasonable assurance for equipment operability.
Procedure changes, associated with opening doors, will be implemented to cope with the SBO event.'
5.
Containment Isolation (Section 7.2.5)
The plant list of containment isolation valves for Beaver Valley Unit 1/2 have been reviewed to verify.that valves which must be capable of being closed or that must be operated (cycled) under station blackout conditions can be positioned (with indication) independent of'the preferred and blacked-out unit's Class 1E power supplies.
No plant modifications and/or associated procedure changes were determined to be required to ensure that appropriate containment integrity can be provided under SBo conditions.
6.
Reactor Coolant Inventory (Section 2.5)
The AAC source powers the necessary make-up systems to maintain adequate reactor coolant system inventory to ensure that the core is cooled for the required coping duration.
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