ML18081B213
| ML18081B213 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 03/13/1980 |
| From: | Mittl R Public Service Enterprise Group |
| To: | Parr O Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8003190558 | |
| Download: ML18081B213 (20) | |
Text
0 PS~G Public Service Electric and Gas Company 80 Park Place Newark, N.J. 07101 Phone 201/430-7000 March 13, 1980 Director of Nuclear Reactor Regulation
-U. S. Nuclear Regulatory Commission
.:Avashington, D.C.
20555 Att:
Mr. Olan D. Parr, Chief Light Water Reactors Branch 3 Division of Project Management Gentlemen:
RHR SYSTEM NPSH AND RWST CAPACITY NO. 2 UNIT SALEM NUCLEAR GENERATING STATION DOCKET NO. 50-311 PSE&G hereby submits additional information concerning RHR System NPSH and RWST capacity in response to your telephone requests for additional information and letters dated August 22, October 12, and October 19, 1979.
This letter supplements our previous letters dated May 17, October 4, and November 8, 1979, and responds to concerns raised at a meeting held with representatives of your staff 'on February 25, 1980.
Calculations of NPSH available to the RHR pumps while operating in the recirculation mode have been performed for the large and small break LOCA using the most conservative assumptions and are enclosed as Attachments A and B, respectively.
Attachment C provides the basis for RWST Technical Specification setpoints consistent with these analyses.
These analyses also include pressure drop calculations across the containment sump screen.
Confirmation of sump pH with the RWST operating parameters used in these calculations was performed.
A maximum boron concentration of 2200 ppm in the RWST, a minimum spray additive tank volume of 2310 gallons, and the RWST low level alarm set at 150,500 gallons (usable volume of 135,000 gallons, unusable volume of 15,500 gallons) will assure a pump pH of 8.5.
Containment sump model testing will be performed.
A description of the proposed model test program is provided in Attachment D.
The Energy People 8 0 031 90~S"'6 1300) sf:
1/1 95-0942
e Dir. Nuc. Reactor Reg. 3/13/80 It is our intent to perform a test to verify the adequacy of the anti-vortex plates in the RWST.
This test will be performed prior to initial fuel loading and the results submitted for your review.
An analysis has been performed to verify sufficient RHR flow to the core in the event of an RHR.pump failure.
This analysis is provided in Attachment E.
Test data for the No. 22 RHR pump to assure sufficient NPSH is available under the most conservative hydraulic pumping configuration will be submitted in the near future.
Should you have any further questions in this regard, please do not hesitate to contact us.
Encl.
Very truly yours,
'{:1~
R. L. Mittl General Manager -
Licensing and Environment Engineering and Construction
RHR PUMP NPSH DURING RECIRCULATION MODE LARGE BREAK LOCA UNIT NO. 2 SALEM NUCLEAR GENERATING STATION A. Assumptions Attachment A
- 1. Two RHR pumps running at 4,800 GPM each (Note: orifices placed in the RHR discharge limit run out flow to less than 4, 8 0 0 G PM) *
- 2. Containment sump filled to El. 81'-9" by having injected minimum (worst case) available RWST contents and four accumulators.
- 3. Water at saturation (14.7 psia and 2120F).
- 4. Both the inner and outer sump screens 50% obstructed.
- 5. For hf of pipe fittings, the highest hf (worst case) was used in each case from among several different reference handbooks.
For sump screen areas, minimum effective areas were used (screen panel dimensions rounded downward).
~ 22.0 ft. H20 (from RHR pump curve, required extrapolated)
=
p
+ z p
hf available amb.
vp
- . where P
= ambient pressure, absolute, ft. H20 amb.
z
= elevation head, ft. H20 p
= vapor pressure of water, vp
= head loss due to dynamic hf friction losses per assumption #3, P
= P
, so:
amb vp NPSH
= z - hf avail ft. H20
- c.
- 1.
- 2.
Attach. A Page Calculations For z (elevation head)
Containment Sump water level = El. 81' 9"
( Re f. - PS d wg RHR Pump centerline level
= El. 46' 10" 2 0 4 8 0 8 -A - 8 7 5 2 )
- z
=
34.9' For hf (dynamic head loss)
F 1 ow i n to s ump s c re en s = ( 2 )
( 4 8 0 0 G PM)
= 9, 6 0 0 G PM Flow into each pump suction= 4,800 GPM Kinematic viscosity @ 2120F = 3xlo-6 ft.2/sec. = ~
- a.
Outer sump screen
-..296 flow passages, N2.4' h x l"(0.0833')w x 1-1/4" (0.1042')d For each passage, wetted perimeter = (2) (2 *. 4' )+
(2) (0.0833') = 4.97 ft.
D~
= (4) (Area)/(wetted perimeter)
= (4) (2.4x0.0833)/(4.97) = 0.161 ft.
A~
= (296 passages) (2.4 x 0.0833) = 59.2ft.2 50% obstructed~ A~ = 59.2/2 = 29.6 ft.2 V
= Q/A
=[ (9600 GPM) (0.1337 ft.3/gal) ]/
[ (29.6 ft.2) (60 sec./min.)]
= O. 7 22 fps
=
(0.722 fps) (0.161 ft.)/(3x10-6 ft.2/sec.)
= 3.88 x 104 For Nr < 2000, f = 64/Nr Note:
Since Nr) 2000, above formula not valid, but in the absence of alternate formuTae for non-round passages, will use this formula to "ballpark" hf and apply substantial safety factor.
At ta ch. A.
Page f = 64/Nr = 64/3.88xlo4 = l.65xlo-3 = 0.00165 hf=
(fL~2)/(2gD) =
(fL~2)/(64.4D)
= (0.00165) (0.1042) (0.7222)/(64.4 x 0.161)
=
0.0000864 ft. H20
~ negligible
- round up to O. 1 ft
- H 2 O b
- In n e r s urn p s c re en 1/8" screening,..,60% total area= open area (40%
blocked by wire).
For each mesh opening:
0.125" (0.0l')h x 0.125" (0.01') w x 0.120" (0.0l')d wetted perimeter= (4) (0.125") (12 in/ft) = 0.042' o.125"] I (0.042') = 0.0103*
x 12
= (-9 ft2 /panel) (8 panels) = 72 ft.2 With 1/8" screening, 60% open * (72 ft.2) (0.60) = 43.2 ft2 50% obstructed=> A~~
= 43. 2/2 = 21.6 ft.2 V = Q/A
= [(9600 gprn)
(0.1337 ft.3/gal)]/[21.6 ft.2)
(60 sec/min)]
0.99 fps Nr = VD/-V = (0.99 fps) (0.0103'03xl0-6 ft.2/sec)
- 3. 4 x 1 o3 For NR < 2000, f = 64/NR Again using this formula, even though NR > 2000:
f = 64/3.4 x 103 = 1.88 x 10-2 = 0.0188 hf= (fL v2)/(64.4D) = (0.0188) (0.01') (0.992)/
(64.4 x 0.0103)
= 0.0028 ft. H20
~ negligible
- . round up to 0.1 ft. H20
i I
- c.
Suction Piping Losses Attach. A Page Re f ( 1 ) Dwg~ No
- 218 21 0 -A-8 9 0 1-1 3 (2)
~r,ane "Flow of Fluids" Paper No. 410, 1974 (3) DeLaval Engineering Handbook, 3d. ed., 1970 (4) Cameron Hycraulic Data (I-R), 15th ed., 1977
}:Fittings if 21 RHR Pump square edge inlet, 18"f reducer, 18" -.14"cf gate valve, open, 21SJ44, goo SR ell [vert~horiz]
14"+ 1~[
4 50 4 50 goo goo ell ell (El S0'0"...,46'10")
I {
LR ell LR ell Tee, 14"xl4"xl4", line flow goo LR ell strainer (no basket; for start-up only) g o o.., SR e 11 ( up i n to pump) pump inlet; assume square edge inlet, 14"+
=
straight piping -
straight piping -
ow 15 I
.. so I l =t {
square edge inlet, 18"'
reducer, 18"~14"+
gate valve, open, 22SJ44, 14"+
goo SR ell [vert*horiz]
goo LR ell goo LR ell goo LR ell (El 50'0".. 46'10")
goo LR ell Te e, 14 n x l 4 n x 1 4 II,
1 i n e f 1 0 w strainer (no basket; for start-up only) goo LR ell goo
~sR el 1 (up into pump) pump inlet; assume square edge inlet, 14" 18"cf>
14" ct straight piping -
straight piping -
f\\115' 1\\190 I hf ii> hf 21
- .Use 12 2 for ca 1 cs (2-goo ells and go* -
14" pipe vs. 2-450 ells and 80'-14" pipe)
Using #22 RHR Pump Suction, 4800 gpm:
Item (s)
Quant !L
,..:;.~.
- ~.
14". square-edge inlet l
L' = 40 18"+ square-edge inlet 1
L' = 53 open 14" gate valve 1
L = 13 TI Equiv.
Attach. A Page length, ft.
40' ( 14"4> )
53' (18"~ )
16' (14"¢ )
Ref
( 3)
( 3 )
( 4 )
18"-..14"4> reducer 1
( 6) hf = 0.3 ft. H20
( 5) 900 SR ells, 14"ep 2
L
= 30 71' (14"tf> )
( 4 )
TI 900 LR ells, 14"+
L = 20 117' (14"4>)
( 4 )
o tee, 14"xl4"xl4" line flow 1
L
= 20 24' (14"4>)
( 4 )
D straight piping, 18"~
15' 15' (18"~ )
straight piping, 14" cl>
90' 90' (14"cp )
NOTES:
(1) 14" = 1.17' (2) 18" = 1.5' (3) DeLaval (4)
Crane (5) Cameron V14"'
K
=
d~l't\\tl \\I = 1
- 1 7 I d 2 = d llU!t.
= 1
- 5 I
= 0
- 5 ( 1-d 1 2)-'. (~J * = ( 0
- 5 ) { 1 -
- 1. 1 7 2 \\
I (9) I
~
'fs1n 2
~~Sin 2
= O
- 1 9 6{s i n {!) l max
- Si n = 1 ~
max
- K = 0
- 1 9 6
=
( 4 8 O O GAL)
( 2
- 2 2 8 x 1 o-3 ) I <!!'. x 1. 1 7 2 ) = QI A MIN 4
= (1.07 x iol)/(1.08) = 9.91 fps hf =IS \\!,2 = (0.196) (9.912)/64.4 = 0.299 ft. H20 2g
Attach. A Page equiv. length~~:x h f:
14 ""'
4 0 I +.l.6 I* + 71 I + 11 7 I + 2 4 I + 9 0 I = 3 5 8 I 14~
hf 4800 gpm
= (2.6 ft.
H20/lOO') (3.58-lOO'i) = 9.31 ft. H20 l 8"cf 53 I + 15 I
= 6 8 I 18" I hf 4800 gpm
= (0.73 ft. H20/lOO') (.68 -
100~ = 0.5 ft. H20 reducer:
(prev. page) hf= 10.11 ft. H20 hf = outer screen + inner screen + piping
= 0.1 + 0.1 + 10.11 (ft. H20) hf= 10.31 ft. H20
- d.
Final NPSH Calculation
- . N PS H av a i 1 = 3 4. 9 '
-10. 31 '
= 2 4. 6 ft
- H 2 O 24.6>22.o NPSH ayail > _NPSH reqd by ?*6 ft. H20, even with maximum conservatisms
- e.
Discussion of Volume of Water Injected The physical limit that water will build up to at the injection phase is Elevation 81'9".
The NRC has cal-culated that 28,969 cubic feet (approximately 216,688 gallons) of water will be required to reach this elevation.
PSE&G has calculated that 29,970 cu. ft.
(approximately 224,176 gallons) wili be required.
Attach. A Page For purpo.ses of this analysis, it can be seen that 217,892 g~~lons wil be the minimum volume of water injected. ~Figure 1 shows the various setpoints in the RWST a**nd shows the instrument error bands assumed by the NRC.
Since 224,176 gallons are required to achieve elevation 81' 9", and 217,892 gallons are available, water level will reach l" lower (81' 8"),
decreasing the surplus NPSH by 0.07'.
Note that even with maximum conservatism applied at every point is the analysis, NPSH avail>NPSH req'd.
As can be seen from Figure 1, the minimum volume that will be injected from the RWST is 193,000 gallons.
This is the volume between the Technical Specifica-tion minimum and the Low Level alarm where RHR flow is terminated less two instrument error bands.
In addition, during a large break LOCA, the four ac-cumulators will discharge adding a minimum (by Technical Specification) of 6223 gallons eac~ hence:
Volume Injected= 193,000 gal. + (4) (6223 gal) = 217.,'892 gal.
3P 1 05/11-A
sAM GENERATING STATIOl~
UNIT NO. 2 Attachment A
- J... STRUCTURAL VOLUME REACTOR conTAINME~T VOLUMES TO ELEVATION 81'-9" e
LOCATION CU. FT.
Elevator Pit
~
279 Containment Sump-,
394 Outer Annulus 'l're~~h 435 16" Drain Pipe 12 12" Drain Pipe 27 TO ELEVATION 78'-0" l,147 t~ter Annulus (El.78' to 81 1-9")
25,777 Inner Annulus (El.81' to 81 1-9")
3,745 TOTAL *********** ~ *********. 30,669 B. EQUIPMEUT DISPLACEME!\\T EQUIP?rnr.T (4) Accumulators and Piping Large Bore Piping Rege~eretive Heat Exchanger Excess Let-dovn Heet Exchanger Pressurizer Relief Tank TOTAL. *****.**** I **********
C. NET VOLU!*~E TO ELEVATIO~l' 81 '-9" Stru~tural Volume Equipment Displacement NET VOLUME ****************
CU. FT.
484 56 3 6 150 699 30,669 699 29,970 D. VOLUME OF DRAIN TANK PIT TO ELEVATION 81'-9"
- Volutr.e Equipment Displacement IET VOLUME *****************
E. VOLUME OF REACTOR CAVITY TO ELEVATION 81 1-9"
- 2,046 93 l,953 Volume 12,599 Zquipment Displacement 2,l~t NET VOLUME **************** l0,4t
- 7. TOTAL VOLU~E OF CONTAINMENT TO ELEVATION 81'-9" Tota 1 C Total D Tota 1 E 29,970 1,953 10,444 TOTAL ********************* \\3,367 CUBIC FEET
- Will not flood until veter level exceedc Elevation 81'-9"
RHR PUMP NPSH DURING RECIRCULATION MODE SMALL BREAK LOCA UNIT NO. 2
.,4-SALEM NUCLEAR GENERATING 'STATION A.
Assumptions ATTACHMENT B
- 1.
A LOCA of such a size that RCS pressure is main-tained above the accumulator discharge pressure by two Charging/Safety Injection pumps and two Safety Injection pumps.
- 2.
To insure that the volume eqµal to Elevation 81'9" is available in the Containment Sump, the RWST must be pumped to a level 13,200 gallons below the Low Level Alarm.
- 3.
In the small break LOCA situation, the Low Level Alarm point is not as critical as in a large break LOCA since the RHR pumps are not operating in the small break injection phase.
This still allows the operator 105,600 gallons in the RWST to complete the switchover to recirculation line-up.
B.
Calculations No detail calculations are presented for this case for the following reasons:
- 1.
Since friction loss (hf) is a second-order function of flow and the total RHR flow rate to two Charging/
Safety Injection pumps and two Safety Injection pumps is approximately 1500 gpm, it is obvious that the dynamic head loss will be less than for the large break where RHR flow is approximately 4800 gpm.
The available head is then greater and the required head less than the large break situation (NPSH required at 1500 gpm is approximately 8 ft.).
ATTACHMENT B (Cont'd)
- 2.
Even if an RHR pump was assumed to operate at 4800 gpm, -thus requiring 22 ft. NPSH, the available head would:,.be greater than the 24.6 ft. calculated in Attachment A.
Therefore, adequate NPSH is available during the recircula-tion phase of a small break LOCA.
3-11-80 2Pl 43/44 A
ATTACHMENT C RWST SETPOINTS
- ... ALEM UNITS 1 AND 2
- 1*
As a result of the February 25, 1980 meeting with the NRC, the following changes will be made to the RWST setpoints:
Tech. Spec. Min. -
364,500 Gals. (from tank bottom)
Hi-Alarm -
376,600 gals. (from tank bottom)
Lo-Alarm -
150,500 gals. (from tank bottom)
Figure 1 reflects the new setpoints and instrument errors assumed (as required by the NRC).
The bases for the new setpoints are as follows:
NRC REQUIREMENTS:
- 1.
Given a postulated LOCA, the containment sump must be filled to Elev. 81'9" (217,000 gals.) before the RHR pumps have adequate NPSH and can be transferred to sump suction.
For a large break LOCA, the water which fills the sump may be considered as corning from the RWST and the accumulators.
For a small break the water may only come from the RWST.
- 2.
Instrument error is 10,500 gallons and must be taken into consideration when determining setpoints for the RWST.
This error must be assumed to occur in either the high or low direction either of which may be possible at the time of a postulated LOCA.
- 3.
The low-level setpoint must be set high enough to insure a sufficient volume available to allow the operator to switch over from injection to recirculation given the worst case single failure.
The single failure may be considered as one which maximizes outflow from the RWST, i.e., minimizes time available to the operator to complete the switchover.
Instrument error must be accounted for in determining this setpoint.
PSE&G RESPONSES:
- 1.
The Salem Unit 2 Tech. Specs. stipulate that the minimum volume available in the accumulators is 6223 gallons each.
Since four accumulators are provided, the total volume available is 24,892 gallons.
This results in the requirement that 192,108 gallons of water be injected from
the RWST.
The setpoints and minimum Tech. Spec. volume of the RWST will be adjusted to insure that a minimum of 193,000 gallons of borated water will be supplied by the RWST via the ECCS pumps.
(For a discussion of actual sump geometry calculations.;:0nd actual versus required NPSH see Attachment A.)
\\
For the case of a small break LOCA, the RWST water may be injected beyond the low-level setpoint to insure adequate NPSH for the RHR pump~ if necessary, while also leaving sufficient volume for the operator to perform the switchover procedure.
- 2.
Instrument errors of the magnitudes and directions as required by the NRC will be assumed (see Figure 1).
- 3.
The worst single failure which relates to RWST operation is defined as one which reduces the amount of time available to the control room operator to complete the changeover from injection to recirculation.
The most limiting factor at Salem would be the inability of the oper-ator to trip one RHR pump.
This would increase the amount of water drawn from the RWST during the process of change-over from injection to recirculation by an amount corres-ponding to the flow rate of one RHR pump (see Table I).
The expected volume of water to be used by the operator during the switchover from injection to recirculation is 103,475 gallons.
The low-level setpoint will be set high enough to include both this volume and the instrument error which must be assumed (see Figure 1).
For the small break LOCA situation, the above mentioned single failure does not apply; therefore, less volume is required to complete the switchover (Table I).
In addition, the operator is not under the stringent time restrictions (due to reduced flow out of the RWST) as for a postulated large break LOCA.
Therefore, all water required for ade-quate NPSH may be supplied by the RWST.
Enough water will remain in the tank to allow the operator to change over to recirculation before the RWST is depleted.
In addition to the NRC requirements, other operational requirements must be met.
These are:
- 1.
The hi-alarm must actuate before the tank overflow nozzle is reached given a low instrument error.
- 2.
The hi-alarm must actuate with actual tank volume at some. point above the minimum Tech. Spec. limit given a high instrument error.
- 3.
The lo-lo alarm must envelop the volume of water considered unusable due to the location of the outlet nozzles and the volume of water between the instrument taps and the outlet nozzles *
"'-'""=""'
~;
- 4.
The lo-alarm mupt be set at a point high enough i'n the RWST to~llow the containment spray pumps to run long enough in proportion to the RHR, SI, and CHG. Pumps to deliver the required amount of NaOH to the containment sump to meet sump pH requirements.
As a result of these considerations, the maximum boron con-centration in the RWST must be 2200 ppm and the NaOH\\volume requirements must be 2310 gals. to tank (spray additive) maximum.
M PBO 28/06 1/3
TABLE I
CHANGEOVER DEPLETION ANALYSIS OPERATOR ACTION Stop #21 and #22 RHR Pumps and either
- 21 or #22 Cont. Spray Pump Close RHR Pump Suction Valves 'which connect RHR System to RWST (21 RH4 and 22 RH4 or 1SJ69)*
Open RHR Pump Suction Lines to Cont.
Sump (21SJ44 and 22SJ44)*
Close RHR Crossover Line Valves 21RH19 and 22RH19 Start 21RHR Pump Start 22RH~ Pump *
- Close SI Pumps Miniflow Line Isol.
Valves 2SJ67 and 2SJ68 Open 22SJ45 (Aligns 22RHR Pump Disch.
to Chg. Pumps Suction) and open 21SJ45 (Aligns 21RHR Pump Disch. to SI Pumps Suction)*
Open Parallel Valves (21SJ113 and 22SJ113) in Common Line Between SI and Chg. Pumps Suctions TOTAL TIME REQ'D TO COMPLETE ACTION (MIN) 2 2.5 1
1
- 1. 5 1.5
- 1. 5 1
1 13 VOLUME RWST USED TO COMPLETE ACTION (GALLONS)
NORMAL SINGLE FLOWRATE FAILURE 28,600 28,600 10,250 19,750
., i '
4,100
\\;_ '* :>*t~, I 1,9ob' 4,100 7,900 6,150 11,850 6,150 6,150 11,850 4,100 7,900 3,525 7,725 73,125 103,475
- For single failure, the operation of valves associated with the affected RHR pump would not be performed.
- For single failure, step would not be performed.
6
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- MODEL TEST PROGRAM Z.: CONTAINMENT SUMP
~
NO. 2 UNIT ATTACHMENT D SALEM NUCLEAR GENERATING STATION The model test of the containment sump design configuration will be performed to provide verification of design criteria as described below:
Objective To verify that the design criteria identified below with the RHR pumps operating in the recirculation mode, drawing suc-tion from the Containment Sump following a postulated LOCA.
Design Criteria The following design criteria and assumptions will be verified by the model testing:
- 1.
Head loss across the sump two-stage inlet screening and sump anti-vortex baffles will be established and verified to be less than 2.0 feet of water, even with both inlet screens 50% plugged or obstructed.
- 2.
Vortexing does not occur in or around the Containment sump.
- 3.
Vortexing (or excessive fluid rotation) does not occur in the 18-inch or 14-inch pipelines leading from the sump to the RHR pump suctions.
- 4.
Establish water level differentials, if any, across the inlet screens at design flows.
Physical Scope of Model The scale model will include:
- 1.
The Containment Sump, including the two-stage sump inlet screening, sump anti-vortex baffling, the drain lines and drainage flow into the sump.
- 2.
The containment area surrounding the Containment Sump to the extent that it affects sump performance (e.g.,
vortexing).
- 3.
The 18-inch and 14-inch piping connecting the Contain-ment Sump and RHR pump suctions.
M P8025/12 1
.* FLOW DELIVERY TO CORE
~N RHR PUMP FAILURE ATTACHMENT E During the recirculation phase following a large break LOCA, one RHR pump would normally be lined up to feed to the cold legs and one RHR pump lined up to feed to the Centrifugal Charging pumps, Safety Injection pumps, and the Containment Spray Header.
If one.RHR pump was to fail, the remaining RHR pump can be lined up to feed either of the two paths.
An analysis has been performed to verify that sufficient water reaches the core in the event the operating RHR pump was inadvertently lined up to feed both paths.
The eleva-tion difference between the RHR pumps and the spray header in such that this is the path of greatest resistance.
Accordingly, all flow will be delivered by the other paths into the core. Westinghouse has confirmed this determination.
Flow to the core with one RHR pump feeding the Centrifugal Charging pumps, the Safety Injection Pumps and the spray header has been determined and compared with the core boil-off rate.
The earliest time when the RHR pumps would be used to feed the Containment Spray Headers would be when the RWST Low-Low Level Alarm point is reached.
At this point (elapsed time of approximately 32 minutes), the core boil-off rate is approximately 70 pounds per second, based on 10CFR50 Appendix K decay curves, which includes a 20% uncertainty factor.
Assuming the worst case failure (i.e., electrical train B), one RHR pump and one Centrifugal Charging pump would be unavailable.
The flow from the remaining RHR pump would therefore go to one Centrifugal Charging pump, two Safety Injection pumps and the spray header.
For a hot leg break, where all flow from the three ECCS pumps reaches the core, the flow is approximately 164.4 pound per second or 2.35 times the boil-off rate.
For a cold leg break where one-fourth of the ECCS flow is assumed to spill out the break, the flow to the core is approximately 129 pounds per second or 1.84 times the boil-off rate.
With the conservatism in this analysis, PSE&G considers this factor of 1.84 to provide adequate assurance that the core will be provided with a sufficient flow of cooling water.
M P8025/12 2
f
. - j Westinghouse Electric Corporation Water Reactor Divisions Nuclear Service Division Box 2728 Mr. F. P. Librizzi, Gen2ral Manager Electric F'roducti on Public Service El ectr*i c & Gas 80 Parl~ P"J ace Newark, N~w Jersey 07101
Dear Mr. Librizzi:
Pinsburgh Pennsylvania 15230 PSE-79-574 August 1 O, 1979
Subject:
Maximum Bo1~n Concentration in Refueling Water Storage Tank
Reference:
F. Noon's Letter PSE-79-528 dated March 16, 1979 Per the request of your Mr. T. tL Taylor, ~!estinghouse has investigated an upµ::;r lir.rit Lit110n cc111.:t~r.trat*iun uF 2200 µpin in the Refueling Water Stor*age Tank (R~iST), in addiUon to the previously investigated 2500 ppm (see referenced 1 e tter).
TI1e results of accept ab 1 e tech. specs. to accorrmodate these concentrations are shown below~
RWST Low RWST Vo 1 u:r;e RWST Boron NfOH Vo 1 ume Al arm Volume
. ( g a 11 on s)
Concentration (ppm) gallons)
~
350,000 to 400,000 2000 to 2200 2310 to tank max.
135,000 350,000 to 400,000 2000 to 2500 2568 to tank max.
158, 000
- Sincerely, p,.,._*.F. Noon, Manager Y
~
Eastern Region & WNI Support R. E. Carter:cam
- ~*'.