ML19290F006
| ML19290F006 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 03/13/1980 |
| From: | Linder F DAIRYLAND POWER COOPERATIVE |
| To: | Gammill W Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19263F948 | List: |
| References | |
| LAC-6822, NUDOCS 8003170441 | |
| Download: ML19290F006 (3) | |
Text
4 IlitHiYLitNIb 1*0 WEIT C00l*Eltat TR VE Ba 0,our, 01' condn h
54601 March 13, 1980 In reply, please refer to LAC-6822 DOCKET NO. 50-409 United States Nuclear Regulatory Commission Attn:
William Gammill, Acting Assistant Director for Operating Reactor Projectr Division of Operating Reactors Washington, D.
C.
20555
SUBJECT:
DAIRYLAND POWER COOPERATIVE IA CROSSE BOILING WATER REACTOR (LACBWR)
PROVISIONAL OPERATING LICENSE NO. DPR-45 ADEQUACY OF STATION ELECTRIC DISTRIBUTION SYSTEM V_OLTAGE FOR TIIE LA CROSSE BOILING WATER REACTOR
Reference:
(1)
NRC Letter, Gammill to All Power Reactor Licensees, dated August 8, 1979.
(2)
DPC Letter, Linder to Ziemann, LAC-6719, dated January 2, 1980.
Gentlemen:
Your letter (Reference 1) identified the requirement for us to review the electric power systems at LACBWR to determine analyti-cally if, assuming all onsite sources of AC power are not avail-able, the offsite power system and the onsite distribution system is of suf ficient capacity and capability to automatically start as well as operate all required safety loads.
Guidance on evaluating the performance of electric power systems with regard to voltage drop was provided with your letter.
Our letter (Reference 2) discussed our recent actions with regard to the required review.
We expect to issue a report responding to the requirements of your letter prior to April 11, 1980.
The determinations of electrical system operability, capacity and capability are being performed on an expedited basis by one of our technical consult-ants, Sargent & Lundy Engineers.
L\\
s 0 031' U UI
4 William Gammill, Acting Assistant Director LAC-6822 for Operating Reactor Projects March 13, 1980 United States Nuclear Regulatory Commission Page 2 In the meantime, the following applicable information is sub-mitted for your consideration:
1.
The LACBWR station is a one-unit boiling water reactor rated at 48 MW electrical.
The unit has one dedicated reserve auxiliary (s ta r t-up) transformer rated at 5000 KVA.
Enclosed is Drawing No. 41-503621, Revision 7 - Single Line Diagram, Unit 1, Part 1, LACDWR Generator Plant, which shows the LACBWR of f-site and on-site power distri-bution system.
2.
By design, the reserve auxiliary (s ta r t-up) transformer is of adequate size to provide proper voltage to the on-site distribution system with both on-site diesel genera-tors out of service.
No manual load shedding is required.
The reserve auxiliary (s tar t-up) transformer is rated at 5000 KVA; total load during worst case start-up conditions has never exceeded 3000 KVA.
This transformer is a dedi-cated unit used only for the LACBWR in-plant distribution system with no external connections.
3.
The Dairyland Power Off-Site Distribution System "69 KV Line" usually operated between 70.8 to 73.2 KV.
This line which is connected to feed the reserve auxiliary (start-up) transformer is regulated by automatic tap changers, which have kept this line voltage between 70.8 and 73.2 KV.
No frequency variations or voltage degradation has been ex-perienced within the plant since plant operation began, approximately twelve (12) years ago.
During this twelve (12) year p2riod, we have experienced some three hundred eighty-one (381) s ta r t-u p s.
The two (2) Emergency Core Cooling Pumps are of small size, with fif ty (50) horse power electric motors; this represents a very small portion of the start-up load.
4.
Manual load shedding is not required during adverse plant conditions, that is, loss of load, plant scram or loss of off-site power.
We have experienced all of these unusual conditions several times during the past twelve (12) years of plant operation.
We feel that the LACBWR design is capable of providing electrical power of sufficient capac-ity and capability required to pcwer both the safety and non-safety loads without voltage degradation.
All safety loads tha t might not transfer to the diesel generators could remain on the reserve auxiliary (s ta rt-up) trans-former and would be capable of starting without adverse affect to the equipment.
e e
William Gammill, Acting Assistant Director LAC-6822 for Operating Reactor Projects March 13, 1980 United States Nuclear Regulatory Commission Page 3 5.
With the Dairyland "69 KV Line" operating at a higher distribution voltage, we have found that in the past twelve (12) years, th!" voltage has not dropped below the rated 69 KV.
6.
The Nuclear Regulatory Commission Electrichi SEP Inspec tor s have determined that the safety loads required during a LOCA would be automatically started through existing actu-ating devices.
No sequential loeding of any portion of the off-site or on-site power distribution system is needed to assure the power provided for all safety is within the required voltege limits when feed from the off-site power system througn the reserve auxiliary (start-up) transformer.
7.
Our past operating experience ha-shown that our reserve auxiliary (start-up) trans f ormer has only been essentially two-thirds (2/3) loaded during all plant operations and transients experienced to date.
The total load of emergency powered equipment without the use of the two (2) emergency diesel units would be less than five hundred (500) KU.
If there are any questions regarding this response, please con-tact us.
Very truly yours, DAIRYLAND POWER COOPERATIVE lbar db IQ rrank Linder, General Manager FL: RES: dh cc - J. G. Keppler, Regional Director, NRC-DRO III Enclosure (1)