ML17341A002
| ML17341A002 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 06/02/1980 |
| From: | Eric Turner HOUSTON LIGHTING & POWER CO. |
| To: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| IEB-80-05, IEB-80-5, ST-HL-AE-469, NUDOCS 8006300578 | |
| Download: ML17341A002 (3) | |
Text
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~ a W P.O. BOX 52S100, MIAMI,FL 33152
.j'Q FLORIDA POWER 6 LIGHT COMPANY June 12, 1980 Mr. James P. O'Reilly, Director, Region II Office of Inspection and Enforcement U.
S.
Nuclear Regulatory Commission 101 Marietta Street, Suite 3100
- Atlanta, Georgi a 30303
Dear Mr. O'Reilly:
Re.
RI I. JPO (50-250, 50-251)
IE BULLETIN 80-05 Florida Power 8 Light Company has reviewed the subject bulletin and offers the following response:
1.
Tanks with cover gas which can be valved to contain RCS water are provided in Table 1.
Also provided are the tank design pressures, their system designations and volumes.
As requested in the bulletin, our evaluation will be limited to low pressure tanks, or tanks with an internal design pressure of 15 psig or below.
- Thus, based on Table I, only the CVCS Holdup Tanks and the Refueling Water Storage Tank (RWST) are considered.
Adequate measures have been taken to protect these tanks against vacuum conditions that could result in tank damage.
These measures are discussed in our response to Item 2 below.
2.
The systems reviewed in Item 1 included the Reactor Coolant System, the Chemical and Volume Control System, the Radioactive Waste Disposal Liquids System, and the Safety Injection System.
As indicated in Item 1, the only tanks requiring further consideration are the CVCS Holdup Tanks and the RMST.
The three CVCS Holdup Tanks are each designed in accordance with ASME Section III Class C and have a maximum external pressure capability of ~ 15 inches water column.
Mater can be withdrawn from the tanks via three (3) gas stripper feed
- pumps, each rated at 25 gpm.
A holdup tank recirculation pump, rated at 500 gpm, is used to mix the contents of a tank or to transfer water between tanks.
The gas space in the holdup tanks is vented to the vent header in the Radioactive Waste Disposal Gas System (RMDGS).
A connection to the RWDGS cover gas header is also provided as well as a
backup nitrogen supply to maintain the tanks under positive pressure and prevent inleakage of air.
'ormal operating pressure of the holdup tanks is 3 psig, provided covey gas from the cover gas header is available.
In the event the cover gas header is out of commission, a Nitrogen backup supply has been provided to maintain tank pressure at a minimum of 1 psig.
8II0680057$
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Hr. James P. O'Reilly Page 2
Each holdup tank is provided with two vacuum breaker valves, which will operate automatically if the pressure in the tank decreased below 3 inches (w.c.)
vacuum.
Each vacuum breaker valve has a maximum capacity of 100 scfm when fully open (at a
vacuum of 6 inches w.c. }.
. Assuming that the recirculation pump is operating at runout capacity of 700 gpm and the gas stripper pumps are operating at a rated capacity of 25 gpm
- each, the maximum gas flowrate out of the tank is~ '104 scfm.
The system is designed and operated such that operation of the vacuum breakers is minimized.
The following features are provided to acconplish this:
a)
The tanks are provided with cover gas from the gas decay tanks via the cover gas header with a Nitrogen backup supply.
The N
backup supply pressure regu1ator is capable of supplying 35 scfm (equivalent to ~240 gpm) 9 1 psig set pressure.
b)
The holdup tank recirculation pump stops automatically when the tank pressure decreases to 1 psig.
c)
A low pressure alarm, set at 1 psig is provided in the local control panel to alert the operator of a possible system malfunct ion.
d)
Administrative procedures have been established to prevent transfer of liquid between tanks by gravity unless the respective tank vent line valves are open.
The vacuum protection of the RWST was also investigated.
A calculation was performed assuming that all of the pumps taking suction on the RWST would be operating at their maximum flowrate simultaneously.
The results are that the RWST has sufficient vent capability (a factor of safety of 10e8)
Based on the above discussion, the existing measures for vacuum protection at Turkey Point Units 3 and 4 are adequate and no further modifications are required.
Very truly yours, Robert E. Uhrig Vice President Advanced Systems 5 Technology REU/MAS/cph cc:
Director, Office of Inspection and Enforcement
, Harold F. Reis, Esquire
TABLE 1 TANK SYSTEM qUANTITY VOLUME (Gal)
DESIGN PRESSURE Psig 1-Pressurizer Relief Tank RCS 1/unit 9724 100 Int.
2-Reactor Drain Tank RWDLS 1/unit 350 25 Int.
3.
Volume Control CVCS Tank 1/unit 2244 75 Int./15 Ext.
4.
CVCS Holdup Tanks CVCS 3/2 units 97240 each 15 Int.
5.
Refueling Water SIS Storage Tank 1/2 units 338,000 Atmospheric jv f" "-':
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