Text

Attachment 4, Supplement to Proposed Technical Specifications Change Recirculation Spray System, Calculation, Us (B)-341, Rev. 4 Ccn 1, Containment Atmosphere Iodine Removal Coefficients
	ML062050057
Person / Time
Site:	Millstone
Issue date:	03/15/2005
From:	Cho J; Dominion, Dominion Nuclear Connecticut
To:	; Office of Nuclear Reactor Regulation
References
	06-096 17273.09-US(B)-341, Rev 4
	Download: ML062050057 (24)
	v • d • e

Serial No.06-096 Docket No. 50-423 ATTACHMENT 4 SUPPLEMENT TO PROPOSED TECHNICAL SPECIFICATIONS CHANGE RECIRCULATION SPRAY SYSTEM CALCULATION, US (B)-341, REV. 4. CCN 1.

"CONTAINMENT ATMOSPHERE IODINE REMOVAL COEFFICIENTS" (REDACTED VERSION - NON-PROPRIETARY)

DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 3

Serial No.05-357 Docket No. 50-423 Recirculation Spray System bc Page 1 of 3 bc: (*paper copies as noted; remainder electronic distribution)

Ms. M. B. Bennett - IN2SE Mr. S. E. Scace - MPS 475/5 Ms. L. M. Cuoco - MPS 475/5 Mr. T. L. Breene - KPS Mr. P. A. Kemp - NAPS Mr. B. A. Garber - SPS Mr. D.W. Dodson - MPS 475/5 Mr. P. R. Willoughby - IN2SE Mr. D. J. Leon - MPS 475/3 Mr. B. A. Krauth - MPS 475/5 Licensing File - GOV 02-54B*

MSRC/NOB Coordinator - IN2SE Records Management - (bc original) - IN-GW*

Concurrence:

E. S. Grecheck K. L. Basehore D. M. Bucheit C. L. Funderburk D. A. Sommers J. A. Price/MPS Verification of Accuracy:

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

Serial No.05-357 Docket No. 50-423 Recirculation Spray System bc Page 2 of 3 Action Plan:

1. Implementation Plan - see AR 05004067 Reauired Chanqes to the UFSAR or QA Topical Report:

1. None

Serial No.05-357 Docket No. 50-423 Recirculation Spray System bc Page 3 of 3 Millstone Concurrence:

S. E. Scace D. W. Dodson P. E. Grossman W. J. Eakin M. S. Kai P. F. L'Heureux M. D. Legg R. E. Deconto J. L. Wheeler

Identification Hevision Contidentiality Deliverable Number Number Status Transmittal Status Calculation Temp / Press Profiles US(B)-273 7

Nonconfidential Previously Transmitted Calculation US(B)-341 4 plus CCN 1 Nonconfidential Enclosed Calculation US(B)-372 0

Confidential Enclosed"'

Technical Evaluation M3-EV-04-0014 0

Nonconfidential Enclosed Technical Evaluation M3-EV-04-0015 0

Nonconfidential Enclosed Technical Evaluation M3-EV-04-0032 0

Nonconfidential Enclosed Engineering Record Correspondence 25212-ER-05-0023 0

N/A DNC Product Enclosed US(B)-273 LOCTIC Data Deck Run R2004P07 Nonconfidential On CD at MPS US(B)-273 LOCTIC Data Deck Run R2004PO1A Nonconfidential On CD at MPS US(B)-273 LOCTIC Data Deck Run R2004P08 Nonconfidential On CD at MPS US(B)-273 LOCTIC Data Deck Run R2004T01 Nonconfidential On CD at MPS US(B)-273 LOCTIC Data Deck Run R2004T08

_Nonconfidential On CD at MPS I__-

Note 1: Shaw Group / Stone & Webster has not yet provided a redacted copy of this calculation for transmittal

Approved J/24/02 Effective 1/28/02 TOTAL PAGES: 14 A"

CALCULATION CHANGE NOTICE (CCN)

PAGE I OF 14 AFFECTED CALCULATION/PLANT

[MPI

.] MP2

[ MP3

[] GENERAL CALCULATION NO.

REVISION NO.

CHANGE NO.

N/A 4

001 VENDOR CALCULATION NO.:

VENDOR NAME:

17273.09-US(B)-341 Stone & Wcbstcr, Inc.

CALCULATION TITLE:

Containment Atmosphere Iodine Removal Coefficients REFERENCE 50.59 Evaluation or CCN Supports CCN Supports Other N/A Screen Attached DCRIMMOD/EE?

Process?

YES NO YES ONo OYEs ONO Rcf. No.: DCR M3-04004

Reference:

REASON FOR CHANGE

1. To incorporate the proposed RSS pump start signal which is at or near the RWST Low-Low Level in response to NRC Generic Safety Issue GS1-191 (Refs. 5 and 6). The various iodine removal coefficients calculated in Rev. 4 are re-analyzed using the updated containment conditions (Ref. 1) due to the proposed RSS pump start time.

2. To include additional iodine removal coefficients. The elemental iodine removal coefficients for the simultaneous quench and recirculation spray operating condition and for the recirculation spray only operating condition are calculated. Additionally, the particulate iodine removal coefficient for the recirculatioo.

spray only operating condition Is calculated.

DESCRIPTION OF CHANGE & TECHNICAL JUSTIFICATION The iodine removal coefficients for the various cases are recalculated or newly added as shown in Tables 4, 5, and 6.

NUCLEAR INDICATOR AFFECTED CALC PAGES 0 CATI 0RWQA 0 SBOQA N/A FPQA 0 ATWS.A 0 NON-QA Approvals I (Print Sign Name)

Preparer: Joon Cho Date: 3115/05 ntcrdiscipline Revicwcr:

IA_

Disciplinc: N/A Date: N/A Interdiscipline Reviewer: N/A Discipline: N/A Date: N/A mndcp ndcnt Reviewcr: Chris Mctcalfc "No Comments,"

Date: 3/15/05 Engineering Approvcr Joe Green Date: 3/15/05 Installation Verification o Calculation represents the installed confi t' n and approved licensing condition (Calculation of Record) o3 N/A does not affect plant configuration (c tudy, hypothetical analysis, etc.)

Preparer/Design Engineer: (Print and ign)

Date:

If applicable:

Superseded by Rev.

CCN_

Preparer/Design Engineer: (Print and Sign)

Date:

DCM 05-5A Rev. 010 Page I of I

Approved 11/17/03 Effective 111/21/MR Approved 11/17/03 Effective 11/21/03

,Ai PassPort DATABASE INPUTS CHANGE Calculation Number:

N/A Vendor Calculation Number/Other Page 2 of 14 Revision:

Revision:

I 17273.09-US(B)-341 N/A 4

CCN NO.:

001 Superseded By:

N/A CEHANGES i

(Chg Discipline (Up to 10) CC [A]:

Calc Voided:

["] Yes 0 No Supersedes:

N/A ange Codes [ CC]: "A" = Add; "D" = Delete)

N,L, Q,S,Z CC Unit Project Reference Component Id Computer Code Rev. NoJ M i 2,

(EWA)

Level No.

M3

}"N/A N/A PMMS CODES*

I CC Structure System Component Reference Calculation Rev No.

"CCN CS RSS N/A 12179-US(B)-273 7

N/A S108788-US(B)-371 0

N/A 03705-US(B)-360 0

02 03703.1971-US(B)-350 2

N/A

The codes required must be alpha codes designed for structure, system and component.

NOTE: Avoid multiple item references on a line, e.g., LT 1210 A-D requires four separate lines.

CCj Reference Drawing j

Sheet Rev. No.

N/A N/A N/A Comments:

Referenced By Calculation Impact Impact AR Reference/Calc Change Ref.

Y N

M3ASTLOCA-04052R3 Y

05000969-01 M3ASTREA-04054R3 N

M3ODLOCA-04084R3 N

M3TSCLOCA-04105R3 Y

05000969-01 M3-LOCA94-01048R3 N

88-019-00096RA N

03703.1971 -US(B)-349R I N

_-I -_

_-_I DCM Form 05-5B Rev 009 Page 2 of 2

STONE & WEBSTER, INC.

CALCULATION SHEET REVIEW STATEMENT FOR SAFETY RELATED CALCULATIONS Review of this calculation was based on the methods below:

1)

Review of:

a)

Inputs to ensure that they have been properly selected and correctly used in the calculation. (Check One) i) Limited review (provide justification) ii) Line by line review b)

Assumptions to assure their validity and need for later confirmation.

Initial Upon Completion El 0y-

&k c)

Methodology to assure the appropriateness of the overall approach, its implementation, and the correctness of the specific equations utilized..

Q Limited review (provide justification) ii) Line by line review d)

Results to ensure reasonableness and accuracy e)

If alternate calculation is performed to verify C) and d) check here and attach calculation as an appendix

2)

Check of Calculation (Check One) 0 0

00 VPF-om a) b)

Complete numerical check Numerical check of critical items (state items and justification below)

Administrative check of format and content 3)

ED~M

4)

Comments/Justification Review Methods Selected as Indicated Above Reviewer

(

\\,

Independent Revi* fer Joe Green

-.1* rAILL1 Lead concurrenV*

3a15/05 Date 3/15t05 Date 3/15/05 Date

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER

0. OR W.O NO.

DIVISION AND GROUP CALCULATION NO.

REVISION NUMBER CCN # 001 17273.09 US(B) 341 4

PAGE 4 PURPOSE OF CCN 001 TO REV. 4 The purpose of CCN 001 to Rev. 4 is:

1. To incorporate the proposed RSS pump start signal which is at or near the RWST Low-Low Level in response to NRC Generic Safety Issue GSI-191 (Refs. 5 and 6). The various iodine removal coefficients calculated in Rev. 4 are re-analyzed using the updated containment conditions (Ref. 1) due to the proposed RSS pump start time.

2. To include additional iodine removal coefficients. The elemental iodine removal coefficients for the simultaneous quench and recirculation spray operating condition and for the recirculation spray only operating condition are calculated. Additionally, the particulate iodine removal coefficient for the recirculation spray only operating condition is calculated.

CONFIRMATION REQUIREMENT This CCN 001 does not require confirmation.

COMPUTER PROGRAM No computer program was used in this CCN 001.

REFERENCE/DESIGN INPUTS

1. S & W Calculation 12179-US(B)-273, Rev. 7, "Containment Pressure and Temperature Analysis Following a LOCA", 09/29/04.

2. S & W Calculation 108788-US(B)-371, Rev. 0, "Recirculation Spray Coverage". 12/06/04.

3. S & W Calculation 03705-US(B)-360, Rev. 0, CCN 02, "Quench Spray and Containment Recirculation System Thermal Efficiency", 3/31/98.

4.

Plot R5943, "Spatial Droplet Size Distribution of 47-0714-17 (1713A) Nozzle Applying Surface Area Correction and Spraying Water at 10 psig under Laboratory Conditions" A. M. Shah, Spraco, Inc.,

Nashua, NH (8-14-81) (Attachment A).

5. Engineering Record Correspondence Number, 25212-ER-04-0034, Transmittal of Design Input to Support Containment Reanalysis - RSS Pump Start on RWST Low-Low Level Signal.

6. Design Change Record Number, M3-04004, Change RSS Pump Start Signal from Timer to Start on RWST Low-Low Level Signal.

7. S & W Calculation 03703.1971-US(B)-350, Rev. 2, "Trisodium Phosphate System for Sump pH Control", 5/8/98.

8. NUREG/CR-5950, -Iodine Evolution and pH control", December 1992.

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER J.O. OR W.O NO.

DIVISION AND GROUP CALCULATION NO.

REVISION NUMBER CCN # 001 17273.09 US(B) 341 4

PAGE 5 ASSUMPTIONS

1. The wetted surface area in the sprayed region is conservatively estimated as 50% of heat sink surface area in the sprayed region, considering remaining 50% of heat sink surface areas are not directly wetted by sprayed waters. Additionally, the heat sink surface area in the sprayed region is estimated as the total containment heat sink surface area multiplied by the quench spray coverage fraction.

2. For bounding LOCA dose calculation, the minimum constant quench and recirculation spray flow rates (i.e., 3,870 gpm and 2,581 gpm) are selected respectively among the various LOCA cases analyzed in Ref. 1, while the quench and recirculation spray operating time intervals are determined based on the maximum ESF assumption. Note that the minimum iodine removal coefficients and minimum spray coverage in conjunction with the minimum quench spray operating time interval result in the most conservative LOCA dose calculation.

3. The average mass-mean diameter of the sprayed droplets from two different spray headers with

-different drop size distribution is approximated as flow rate weighted average of each. mass-mean diameter. Since the calculated elemental iodine removal coefficient with average.mass-mean diameter is much higher than the limited value of 20 hr"W (refer to page 9), this approximation is considered to be insignificant.

METHODOLOGY Refer to the methodology section 5.0 presented in Rev. 4.

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER J.O. OR W.O NO.

DIVISION AND GROUP I CALCULATION NO.

REVISION NUMBER CCN 17273.09 US(B) 341 4

PAGE CALCULATION COEFFICIENT FOR ELEMENTAL IODINE REMOVAL THROUGH WALL DEPOSITION Unsprayed Region:

For conservatism, the elemental iodine removal coefficient through wall deposition in the unsprayed region is only calculated for quench spray only operating condition. The major wetted areas in the unsprayed region are the total surface areas of the containment liner and dome (refer to pages 15 through 17 of Rev. 4). The LOCTIC run outputs in Ref. 1 show that the containment liner and dome surfaces (i.e., heat sink cases 7, 8, and 10) become dry (i.e., no steam condensing on the surface) near 2,000 seconds after the accident. Thus, the containment liner and dome are conservatively considered to be wetted surface area in the unsprayed region of the containment atmosphere for the first 1,800 seconds only. The elemental iodine removal due to wall deposition in the unsprayed region of the containment atmosphere will be valid from time 0 second to 1,800 seconds only.

From Ref. 1, the total surface area of the containment liner and dome (Auprayed)

= 34,827 + 22,325 + 30,852

= 88,004 ft2.

From Rev. 4, page 18, the unsprayed containment volume (V,,nrd) = 1,183,800 ft0 Therefore, Xwa1 1ion (udnspray0) = 16.08 (ft/hr) x 88,004 (fte)/1,183,800 (ft3)

= 1.2 hr" (valid between 0 < t S 1,800 sec)

Sprayed Region:

Since the wetted surface area in the sprayed region (Ayd) is not available, it is conservatively approximated based on spray coverage fraction (f1,y) as follows (refer to Assumption 1):

sp,.,* = [Total heat sink surface areas] x f,*y x 0.5e Total heat sink surface area = 933,775 ft2 (Ref. 1) f,*, = VW,,

/ VIo%

Vlow = 2,350,000 ft (Rev. 4, page 17)

"* 50% of heat sink surfaces in the sprayed region is assumed to be wetted by spray.

Therefore, ),.a,

,iio

(,ýmw) = 16.08,.ft/r) x [933,775 (ft) /2,350,000 (ft3)] x 0.5

= 3.2 hr (valid throughout entire transient of spray operation)

The elemental iodine removal due to wall deposition in the sprayed region of the containment atmosphere is applicable over the entire spray operating (i.e., quench only, quench and recirculation, and recirculation only) duration.

DETERMINATION OF ELEMENTAL IODINE REMOVAL RATE CONSTANT DUE TO SURFACE DEPOSITION FOR THE SBLOCA CASES WITHOUT SPRAY ACTUATION FOR 30 MINUTES The calculated 1.2 hf1 of 4a,=,.,p.y) in Rev. 4, page 30 remains valid for all SBLOCA cases with 2" or greater break sizes without spray actuation for 30 minutes.

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER 1.0. OR W.O NO.

DIVISION AND GROUP CALCULATION NO.

REVISION NUMBER CCN # 001 17273.09 1

US(B) 341 4

PAGE 7 ELEMENTAL IODINE SPRAY REMOVAL COEFFICIENTS Quench Spray Only Operating:

The required parameters for the elemental iodine removal coefficient through quench spray are conservatively calculated as follows:

F (volumetric quench spray flow rate) = 3,870 gpm (Ref. 1, LOCTIC run R2004T01: minimum flow rate during quench spray operation)

=i0 3,870 (gpm) x 60 (min/hr) x 0.13368 (fteIgal) = 31,040 fte/hr V (sprayed containment free volume) = 1,166,200 ft? (Rev. 4, page 15)

D (mass-mean diameter of the spray droplets) = 1,100 pi (Rev. 4, pages 21 and 22)

= 3.61 x 10"3 ft t (time of fall of droplets) = 2 x 10-3 hr (conservatively assumed from Rev.4, page 25)

Kg (gas phase mass transfer coefficient) = 900 ft/hr (conservatively assumed from Rev. 4, page 26).

Thus, the coefficient for elemental iodine removal through quench spray (,y)

= (6 x 900 (ft/hr) x (2 x 10") (hr) x 31,040 (ft3/hr))/{1,166,200 (ft3) x (3.61 x 10"3) (ft))

= 80.0 hrW1 Since %,,y is limited to 20 hr'(Rev. 4, page 13), 4~pmy is set to 20 hr 1.

Recirculation Spray Only Operating:

Since the sump solution pH is above 7.0 during the entire period of recirculation spray operation (Ref. 7), the iodine removal by the recirculation spray is considered to be valid. Note that the iodine re-evolution won't occur when the sump pH is equal or higher than 7.0 (Ref. 8).

The required parameters for the elemental iodine removal coefficient through recirculation spray are conservatively calculated as follows:

F (volumetric recirculation spray flow rate) = 2,581 gpm (Ref. 1, LOCTIC run R2004T08: minimum flow rate during recirculation spray operation)

=10 2,581 (gpm) x 60 (min/hr) x 0.13368 (ft3/gal) = 20,702 ft3/hr V (sprayed containment free volume) = 1,102,000 ft? (Ref. 2, page 35)

D (mass-mean diameter of the spray droplets) = 0.00526 ft (see below)

In order to determine the mass-mean diameter, the spray droplet size distribution data which is based on pressure drop across the nozzle is required. The LOCTIC run R2004T08 (PSDER with Sequencer failure case) shows that the spray flow rates are 1,927 gpm for one recirculation header and 654 gpm for other recirculation header which are corresponding to the nozzle pressure drop of 10 psid and 2.75 psid, respectively (Ref. 3). The spray droplet size distribution data for 10 psid and 2.75 psid cases (see Tables 1 and 2) are obtained from Attachment A (Ref. 4) and Ref. 3, Table 1, respectively.

The mass-mean diameters for 10 psid and 2.6 psid cases are calculated from Tables 1 and 2 as follows:

STONE & WEBSTER, INC.

CALCULATION SHEET Table 1: Drop Size Distribution for 10 Dsid Table 2: Drnn Size Di~tributinn f6r ~ 7~ n~id Table 2: Dron Size Distribution for 2 75 nsid fi D,, cm f, x Dj', cm 4 f x D3, cm3 0.001 0.002 0.013 0.049 0.105 0.101 0.120 0.100 0.076 0.064 0.034 0.050 0.053 0.052 0.041 0.027 0.019 0.020 0.012 0.010 0.006 0.004 0.003 0.006 0.005 0.006 0.004 0.003 0.002 0.000 0.001 0.000 0.003 0.002 0.000 0.002 0.000 0.002 0.001 0.001 0.001 0.002 0.0125 0.0175 0.0225 0.0275 0.0325 0.0375 0.0425 0.0475 0.0525 0.0575 0.0625 0.0675 0.0725 0.0775 0.0825

.0.0875 0.0925 0.0975 0.1025 0.1075 0.1125 0.1175 0.1225 0.1275 0.1325 0.1375 0.1425 0.1475 0.1525 0.1575 0.1625 0.1675 0.1725 0.1775 0.1825 0.1875 0.1925 0.1975 0.2025 0.2225 0.2275 0.3025 2.4414E-1 I 1.8758E-10 3.3318E-09 2.8024E-08 1.1714E-07 1.9973E-07 3.9150E-07 5.0907E-07 5.7737E-07 6.9960E-07 5.1880E-07 1.0380E-06 1.4643E-06 1.8759E-06 1.8993E-06 1.5827E-06 1.3910E-06 1.8074E-06 1.3246E-06 1.3355E-06 9.6108E-07 7.6245E-07 6.7556E-07 1.5856E-06 1.5411E-06 2.1447E-06 1.6494E-06 1.4200E-06 1.0817E-06 0.OOOOE+00 6.9729E-07 0.0000E+00 2.6563E-06 1.9853E-06 0.0000E+00 2.4719E-06 0.OOOOE+00 3.0430E-06 1.6815E-06 2.4509E-06 2.6787E-06 1.6747E-05 1.9531 E-09 1.0719E-08 1.4808E-07 1.01 90E-06 3.6045E-06 5.3262E-06 9.2119E.06 1.0717E-05 1.0997E-05 1.2167E-05 8.3008E-06 1.5377E-05 2.0197E-05 2.4205E-05 2.3022E-05 1.8088E-05 1.5038E-05 1.8537E-05 1.2923E-05 1.2423E-05 8.5430E-06 6.4889E-06 5.5148E-06 1.2436E-05 1.1631 E-05 1.5598E-05 1.1575E-05 9.6271 E-06 7.0932E-06 0.OOOOE+00 4.2910E-06 0.OOOOE+00 1.5399E-05 1.1 185E-05 O.OOOOE+00 1.3184E-05 O.OOOOE+00 1.5407E-05 8.3038E-06 1.1015E-05 1.1775E-05 5.5361 E-05 D=. cm f1 x D!, cmI fL x Dia, cm3 0.103815 0.022429 2.6272E-08 1.1713E-06 0.106023 0.026824 5.4889E-08 2.0463E-06 0.099318 0.030487 8.5794E-08 2.8142E-06 0.094933 0.034882 1.4054E-07 4.0291 E-06 0.099787 0.042939 3.3922E-07 7.9001 E-06 0.098849 0.051729 7.0780E-07 1.3683E-05 0.097941 0.065647 1.8189E-06 2.7708E-05 0.098437 0.086889 5.6108E-06 6.4574E-05 0.102074 0.122782 2.3198E-05 1.8894E-04 0.098823 0.250238 3.8750E-04 1.5485E-03 74.194SE-04 1.8614E-03 I 6.2997E-05 457E0 4.5574E-04

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER J.O. OR W.O NO.

DIVISION AND GROUP CALCULATION NO.

REVISION NUMBER CCN # 001 17273.09 US(B) 341 4

PAGE 9 D1o (mass-mean diameter for 10 psid) - 6.2997 x 10"5 /4.5574 x 104

=0.1383 cm D2.15 (mass-mean diameter for 2.75 psid) = 4.1948 x 104 /1.8614 x 10"1

= 0.2254 cm Therefore, the average mass-mean diameter of the spray droplets for both headers

= 0.1383 x (1,927/2,581) + 0.2254 x (654/2,581)

= 0.1604 cm (or 1,604 tt)

= 0.00526 ft t (time of fall of droplets) = 1.2 x 10"3 hr (see below)

The terminal velocity for the 1,604 11 diameter droplet (u,04) is conservatively approximated as Rev. 4, page 25, U1 r, 4 40,000 (ft/hr) x (1,604)1-15 "85/(880)1

= 73,799 ft/hr h (fall height of the spray droplets) =.90.42 ft (Rev. 4, page 15)

Therefore, the droplet fall time = 90.42 (ft) /173799 (ft/hr) = 0.0012 hr K. (gas phase mass transfer coefficient) = 900 ft/hr (conservatively assumed from Rev. 4, page 26)

Thus, the coefficient for elemental iodine removal through recirculation spray ()p)y)

= (6 x 900 (ft/hr) x (1.2 x 10"3) (hr) x 20,702 (ft3/hr)) / (1,102,000 (ft3) x (3.61 x 10") (ft))

= 33.7 h(r Since Xpy is limited to 20 h('(Rev. 4, page 13), Apy is set to 20 hr"1.

Simultaneous Quench and Recirculation Spray Operating:

The required parameters for the elemental iodine removal coefficient through quench and recirculation spray are conservatively calculated as follows:

F (volumetric combined quench and recirculation spray flow rate)

= 3,870 gpm (Ref. 1, LOCTIC run R2004T01: minimum flow rate during quench spray operation) +

2,581 gpm (Ref. 1, LOCTIC run R2004T08: minimum flow rate during recirculation operation)

= 6,451 gpm

=1o 6,451 (gpm) x 60 (min/hr) x 0.13368 (ft?/gal) = 51,742 ft3/hr V (sprayed containment free volume) = 1,515,858 ft3 (Rev. 4, page 27)

D (mass-mean diameter of the spray droplets) = 0.00427 ft (see below)

The flow rate weighted average mass-mean diameter of the spray droplets

= 0.11 x 13,870/ (3,870 + 2,581)) + 0.1604 x 12,581/ (3,870 + 2,581)1

= 0.1302 cm (or 1,302 11)

= 0.00427 ft t (time of fall of droplets) = 1.2 x 103 hr (conservatively assumed as recirculation spray droplets)

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER J.O. OR W.O NO.

DIVISION AND GROUP CALCULATION NO.

REVISION NUMBER CCN # 001 17273.09 US(B) 341 4

PAGE 10 K. (gas phase mass transfer coefficient) = 900 ft/hr (conservatively assumed from Rev. 4, page 26)

Thus, the coefficient for elemental iodine removal through quench and recirculation sprays (*pmy)

= 16 x 900 (ft/hr) x (1.2 x 10") (hr) x 51,742 (ft3/hr)) /(1,515,858 (ft3) x (4.27 x 10"3) (ft))

=51.8 h( 1 Since 1,,,y is limited to 20 hr l(Rev. 4, page 13), X,,y is set to 20 he'.

PARTICULATE IODINE SPRAY REMOVAL COEFFICIENTS Quench Spray Only Operating:

The required parameters for the particulate iodine removal coefficient through quench spray are conservatively calculated as follows:

F (volumetric quench spray flow rate) = 3,870 gpm (Ref. 1, LOCTIC run R2004T01: minimum flow rate during quench spray operation)

=I-3,870 (gpm) x 60 (min/hr) x 0.13368 (ft3/gal) = 31,040 1t3/hr h (fall height of the spray droplets) =.101.67 ft (Rev. 4, page 15)

V (sprayed containment free volume) = 1,166,200 ft3 (Rev. 4, page 15)

Thus, the coefficient for particulate iodine removal through quench spray, (A*cte)

= (3 x 101.67 (ft) x 31,040 (ftWlhr)) / (2 x 1,166,200 (fte)) x (E/D) (ft)

= 4.059 x (EID) hr'

=11 4.059 x 3.048 = 12.37 hr1 (for decontamination factor (DF) < 50)

=10 4.059 x 0.3048 = 1.24 hr 1 (for DF > 50)

Note that DF is defined as Cp (0) / Cp (t), where C. (0) is the initial concentration of particulate iodine in the containment atmosphere and Cp (t) is the concentration at time t.

Recirculation Spray Only Operating:

The required parameters for the particulate iodine removal coefficient through recirculation spray are conservatively calculated as follows:

F (volumetric quench spray flow rate) = 2,581 gpm (Ref. 1, LOCTIC run R2004T08: minimum flow rate during recirculation spray operation)

=1o 2,581 (gpm) x 60 (min/hr) x 0.13368 (ft3/gal) = 20,702 ft3/hr h (fall height of the spray droplets) = 90.42 ft (Rev. 4, page 15)

V (sprayed containment free volume) = 1,102,000 ftW (Ref. 2, page 35)

Thus, the coefficient for particulate iodine removal through recirculation spray (flrate)

= (3 x 90.42 (ft) x 20,702 (ft3/hr)} / (2 x 1,102,000 (ft )) x (E/D) (ft")

= 2.548 x (EID) hr'

=1' 2.548 x 3.048 = 7.77 hr' (for decontamination factor (DF) < 50)

=10- 2.548 x 0.3048 = 0.78 hr' (for DF a 50)

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER J.O. OR W.O NO.

DIVISION AND GROUP CALCULATION NO. I REVISION NUMBER CCN # 001 17273.09.I US(B) 341 4PAGE 11 Simultaneous Quench and Recirculation Spray Operating:

The required parameters for the particulate iodine removal coefficient through quench and recirculation spray are conservatively calculated as follows:

F (volumetric combined quench and recirculation spray flow rate)

= 3,870 gpm (Ref. 1, LOCTIC run R2004T01: minimum flow rate during quench spray operation) +

2,581 gpm (Ref. 1, LOCTIC run R2004T08: minimum flow rate during recirculation operation)

= 6,451 gpm

=Io 6,451 (gpm) x 60 (min/hr) x 0.13368 (ft3/gal) = 51,742 ft3/hr h (fall height of the spray droplets) = 90.42 ft (Rev. 4, page 15: minimum height is assumed)

V (sprayed containment free volume) = 1,515,858 ft3 (Rev. 4, page 27)

Thus, the coefficient for particulate iodine removal through quench andrecirculation spray (Xparcjat8)

= (3 x 90.42 (ft) x 51,742 (ft3lhr)) /{2 x 1,515,858 (ft)) x (E/D) (ft-)

= 4.630 x (E/D) hrf"

=10 4.630 x 3.048 = 14.11 hr"1 (for decontamination factor (DF) <.50).

=1o 4.630 x 0.3048 = 1.41 hr1 (for DF > 50)

DETERMINATION OF TIME INTERVAL FOR SPRAY ACTUATION In the previous section, the iodine removal coefficients are calculated for the 3 time periods (i.e.,

quench spray only operating, simultaneous quench and recirculation spray operating, and recirculation spray only operating). Two time intervals based on the minimum and maximum ESF assumptions which envelope all LOCA cases including Sequencer and MCC failures are shown on Table 3.

As stated in Assumption 2 (see page 5), the time interval based on the maximum ESF assumption is chosen in this CCN for conservative dose calculation.

Table 3: Sprayina Time Interval Quench Simultaneous Recirculation Spray Only Quench and Spray Only Operating Recirculation Operating Spray Operating Minimum ESF Case (Ref: Rev. 1, LOCTIC run 71 < t < 4,610 4,610 St S 9,790 t > 9,790 sec 2004PO1A)

Maximum ESF Case (Ref: Rev. 1, LOCTIC run 71 S t < 2,710 2,710!5 t < 6,620 t > 6,620 sec 2004P02)

_1

STONE & WEBSTER, INC.

CALCULATION SHEET CALCULATION IDENTIFICATION NUMBER J.O. OR W.O NO.

DIVISION AND GROUP I CALCULATION NO. I REVISION NUMBER CCN # 001 17273.09 US(B) 341 4PAGE 12 RESULTS/CONCLUSION The calculated elemental and particulate iodine removal coefficients are summarized below.

Table 4: Elemental Iodine Removal Coefficients in the Unsoraved Region g

g I

n Large Break Small Break LOCA Cases LOCA Cases (2" dia or larger) w/o Spray

,Actuation for 30 minutes X.0 ftA

(.rP.od)

(Wall Deposition) 1.2 h_"1 1.2 h_"1 VunspMyed (Unsprayed Volume) 1,183,800 ft3 2,350000 ft Valid Time Interval 0 <t < 1,800 s 0 t s 1,800 s Table 5: Elemental Iodine Removal Coefficients in the Soraved Reaion Quench Simultaneous Recirculation Spray Only Quench and Spray Only Operating Recirculation Operating Spray Operating (Wall Deposition) 3.2 hr 1 3.2 hr" 3.2 hr" (Spray Removal) 20 hr1 20 hr' 20 hr' 24otar lementaw (Wall Deposition and 23.2 hre1 23.2 hr 1 23.2 hr 1 Spray Removal)

(Sprayed Volume) 1,166,200 ft3 1,515,858 ft3 1,102,000 t*

Valid Time Interval 71 St < 2,710 2,710 S t < 6,620 t > 6,620 sec Table 6: Particulate Iodine Removal Coefficients in the Sprayed Region Quench Simultaneous Recirculation Spray Only Quench and Spray Only Operating Recirculation Operating Spray Operating For DF < 50 12.37 hr" 14.11 hr'1 7.77 hr" For DF Z 50 1.24 hr" 1.41 hr" 0.78 hr'1 VaPrayed (Sprayed Volume) 1,166,200 ft3 1,515,858 ft3 1 102,000 ft3 Valid Time Interval 71 S t < 2,710 2,710 s t S 6,620 t > 6,620 sec

KE'JW.t.e £06ft 60.

4.g,

.e-.*

P 1

4.

4'.

3.

4*****

Cs.

I u1m.ýunnnunn.ýj:....

u

..a....

.a M..44.0.0 S

IT.

-a

!.To m m m.,to....

t:g`g:._.::::*I 60

301 1 N, a

0

.0 r

M munmu

i:.

a-:-

Al

a fli i in M 11:11:H.

1. 1. ;'., 4,.". ; I I : : tý a..

Go*

c...........

4:. on 'a,.

..a mHom m iHiiiiii.

01....-

M 100.09clo 90

......... 4...

MUNIMUMM.:

u IN.....

0... -

M...

.-.a....

NUM N

.0 Pat*.. *0..$

H quuipui

.a out.

M.": I NMIM I.....

a 961404.8..... 0:46G.Vo..

go mmnflwuý.-

'a

. 8 NI: 111 :1.

.11:

- ---.:-. a a 1:

R im 9i"Hi.-IM:

N IM.U.N.N.MV.... =ee......

to

a MMMMOMMUNI........

..................a..

.0 IN

........ I....... 1-

.6.............. M..

H.

np uuu Ginn

.1:.

I.ummc:

Hil, Hd N_ H:

I.......

C.::c:-

t

-nuu m 3n-

-!--ý-=

in

i.

3:.

a.:..$ 4 Goa....

.0..........

mo.

N.

un....a.m.m.

MUNNIONNUMS IREIiii"

..R.iiiiiiiiii. in Go I.-M UNUNIM M OU's

............................ W w n...........

a I our.

unmum.puns I: !Immum m m m un:...

d:::h

.:L.

n.

.a-F Go

-No--

H L

--::a-lHin"I" H.E.M.

i inflin: ii: 1. -.1; iRiii:11 lit Nq

.:t lHAHT. 11 to 1.11 61"MMUMSINI:

H r.....

M UN:...............

ýM to

a.

ov.*C.t...

00.

Q at 111:1

141M IM U

Co.

.3...

M o G.N

.. so Ga.

a..

Munim

'O.O."NIN HUMHU....

Mr.'

H-

.9:' M HUSI I.... N.

HIM.

..6............. I..*........

.. N Hum l.

NNON I

...... im -u-m m.................

C-.-.

S-.u

.u.............

U e.g...

M ii=

S_..N1_-I::IGo_6-H::

.... U606.

Hiii'mic!

M.

too",...

OHHH:

a I:Rnun:...

r...

. to I.........

.......... P.................

=.O:*

Hotta...

6.1:0.0...

0........ I c:- I......

.. I:: I.N GINUM M.ONIM M 's 'Moo

... N..........

-HIM"

.1-iiiiiiii-m-C...

GG "N

'HM"I"U.N.

I

... :I:

wuqulnmu:

HCHH'HH. 'UTMEM... ".. HiFnii.-Heii.

a.

1:ý p1l."

gm pw a

?..a.

a- -

-v a H IM =

Go.1....

1 u...

HUM to.0 mi!...I:

a.!::-

eim uw a:ý..q.......

R":.......

I V, 1:

O n

.......IM M M !IV

............. a.....

F=

C-itulv INIUNUM.M N, a a gee Goa a.. a a**,

a--

........ 0.0

'a Go N

N.

6CH -

_'* M

_W1,

3:

........... UH.H.H.H.

unU nunni:

N ot.

I...............

Goo I.......

0.

p-mma.-munnu W4 I-c:::.

4.4=

I:

upuunn p...

m uR.-cum Go off@

_-tmf

-- :a Go NUM U..

1::.. :::.$to me.

0 ON..

Ic

Uum :

M 11 1 "M an

a on.

.. mmmum

......... 0::::.

NIM a..

M...

1-1 a--

I of.

0.01 HIMIN, 1 -

103

!Inu..

t Go

........... j: 11"IfflIna5g:

mu-!

IOHHHRMEHHý UNHERI"MIMMull.

N:

F. H., 1, ii i u I i

13 i i I.'R.

H.

... :.a..

J..

Hininui.

M c M IN

.:W.....

P.

a HHHHHHH-Vilm:

m-nini-tsunum ":........

u...... I?

f. =...

I......

I. at to

. 4.

a.

El.

'a no ISM S.

H: iuuiu:

"'U461

.0.6

.0... $a..... a...... $.ON-spot.

MUNG"3:1311-I.N.

HP M 9::

UUM: go: 'INN

!.0 u

UN MHUS....

iii":!

gi:

0.

.... Hin tu.

Hunwin-H.

M o.

NOT

1..........

.... 4:r Goa#

3 W., 0*:::,............

it-Go.....

go IN IUMM

r.

'gogiii 16 1%

Go.

a I

Go HUIN Go P

HHHHHHHHHOIC.....3i ir-19

-a

1. 9.0::..:: M.:..............

............ I..............

3i-u V I No

.1:-3..l M ea.

&so IM

sHir, i "M 3:511HUM NSICO.:::: i.,:.........

v_=

MM WHOM* 14,11H.H11119.

H1111111 nii-MUNIIIN IUMNUMMM:...............

MIN M.

Ir mw W18UHUINIEniml.-R.. nn NI c

u1iiiR:

g i

mmunumn:

... 0.. oo-a.. On o-num c !:::

su III r.:..

m m

it.-INNI'l a u a-!-

-G:

m.;

Go HHH",

C:_:::%

N.......

Go p to

... H:..

Upooveat"

- sea H.

IN

-4 tu::c::-

cnum:

1:;::

i:::-

num wmwmmc.

pgmcumn

t:R:giMqp nnp num.m.p.n.

0

-1 VE i

H.U.M.-UN0.1.3t:

3"M 6 HUM:

.CHHH."HHUM.

IRn".

U.""'MIM.Mi

niii3-i:

00 IMUNUMM.".

0 do........ I... 4 M.

.90900

...... 40-1.... !NINUMMMINUM:

M US:

....... I.... a.......

m cm...........

OM :

INIG4.1 0.64.00 wtv.:0.6.,

.4 -

if -

gianummummul

.0-m liIiiiii:

..I M -1 a.M OM j...31 I

= 1 N"No'V........

UMMUG.M: tol.MNUM.M.N:

HUM...

... MINH...

........ HH:.........

ii

1.

0 IMAN":

a:,

............ g........ lijil M

a,"HIM NS UNUEJ"."

It 6,::: 3 Mam iiin.....

N, 1. 0 1:

1: 1. H :.': N.: Ma "M

IM UCH.

I'M flig 11 0:10 *N :`:!i` MY-. tot

10.

N H SISH

.. :N

.. 4.

a goo.

a

... :Co.::[.

n G.

q4I.O.OpM 8:

1. H 11 *::gg 1OW N I

........ W ONUM INUM UMNIG UG313

.1

."OH.HHH."

unnn.696-UMMUMN:

I i UNOMMUNOO

0.

of 06 Im M

"Novefooss

.... 4.459001906... W.G.G.:

Pil""iM M:

lost 0

Hu Mugs N94. -

w 1:11:4 10, U.M.C.,

in for 4,410M Fit HHEMI Hlit"M r M

ur.

I..

IMUM ISUMU.... i "MI:gHt

-G a..

.1 a-I"

.- nu M ilm.

0

-- m ium m -m um :

AM

.0-..

MeM a.

nn-gmn

-n-minnumm" 113i

.4 Hilin-ffi...-

-.1...........

. Go..

iMPH-Hilir-M.M.,

M HE..............

nmn IN3.161:81:

nmuam-= a%

Wan.....

N-0....... I=

I.e.

0M

.0.0".4.1 CN;....

-"a

a : - - - : - !'.. ; I. I : I : I I

. :... Of "UN W. Meet

H 10 :-a of-ii.

Fill ifill-iiii:

a

'M r.M....W

.M UN

... c ic

........ :11iffi futiNcits 3;

a N

Hr![I-tf.

9.

5 40a

. 0.0640.... a.;.

Mg.

. :1=

Mll q

ý!!i:i

-flife

-1

-;On P.

ft v... 4...

4-4.1"inh

...... iffl.-filim.

I=

_::3 pw iign....

I...... tv I: 1: 1. NNN a

.. ?

lp"i'M10

,a a..

a m-111HINH m r.w.-P.

Hil

,?::

Goo.

V. UZ

11 P. H In MR, M. H M=111

ýil I

-- iri MY

.4 a

.4,.

I.

~

Approved 2/11/04 Effective 2/18/04 ATTACHMENT B P 1 OF I Administrative Review Checklist for a Calculation or Calc Change Notice 17273.09-US(B)-341 CALCULATION No.

4 Revision No.

001 CCN No.

Eng Approver (Print/Sign):

Jo GIreen Date:

3/15/05 OVERALL REVIEW ID Page count is correct, all pages are included, the total number of pages documented on the CaldcCCN title page, matches the table of contents.

0 Table of Contents for calculations and CCNs (if applicable) defines the page breakdown on the entire document including body of calc/CCN, attachments, appendices, microfiche, CDs, etc. Refer to DCM 05.

0 The entire calculation/CCN is legible, no correction tape, white out, labels were used.

"- If CCN, CCN number was reserved through DA, prior to submitting document to DA.

0 If calculation revision is being submitted, previous revision was signed-out through DA and all associated CCNs have been accounted for on incorporation block of new revision.

TITLE PAGE "

0 The CaWc/CON is the original, not a copy.

0 Preparer used correct revision of all DCM forms, per prepared date.

T Title is correct.

-] If the lead calc(s)/CCN(s) performing the superseding are pending Installation Verification, each calculation being superseded is also not signed off IV. Calcs being superseded must be placed "ON HOLD" with new lead calc(s)/CCN(s) until Installation Verification is complete.

0 All names in approval blocks have been printed followed by signatures and dates.

0 Person approving calculation/CCN is valid (authorized to sign calculations and CCN's).

0 Installation Verified block is either totally blank (no blocks checked) or either block checked and name is printed followed by signature and date.

DATABASE INPUT SHEET: (PASSPORT INFORMATION) 0 Each calculation being submitted has a completed 5-1 B included (5-5B change form cannot be used for a calc, CCN only).

0 Each CCN being submitted has either a 5-1 B, or a 5-5B included The calculation/CCN number(s) are placed on the..

correct line on the Database Input form.

0 Revision is placed on the correct line of the Database Input form, and numerical, not alpha.

0 Supersede documents are properly referenced if applicable.

0 Form 5-1B has all information filled in, blocks checked or an N/A.

El If form 5-5B was used, all fields above the discipline line must have information filled in, blocks checked or an N/A.

If form 5-5B was used all information being referenced, included the change code (cc) "A'= add or, "D"= delete in the CC blocks.

0 All reference calculations/CCN's documented on database form are the correct format and are valid calculations/CCN's existing in PassPort.

0 All reference drawings documented on database form are the correct format (no vendor dwg. # formats) and duplicate numbers are not listed.

Referenced by Calculation block on database form was filled out or indicates None.

19 Calculation number format is correct, and placed on proper line.

0 Revision is on correct line for calc; or correct box for CCN and numerical not alpha.

El If CCN, CCN number has been documented in the CHANGE NO. Block, and format is correct.

0 A Nuclear Indicator (QA status) has been checked on the title page.

0 All other fields on the cover sheet have information filled in, blocks checked, or an N/A.

Executive summary/reason for change area has proper posting of superseding, VOID, or PassPort Data Sheet info.

El If calculation is being superseded or calc(s)/CCN(s) is performing the superseding, the additional required calc(s)/CCN(s) is in the package.

DCM 05-001D Rev. 000 02 Page 1 of I I

QA 0 Non-QA [3 DB or LB document change required? yes []no [

TECHNICAL EVALUATION for Sump pH Impact Review for RSS Start on Low-Low Level Millstone Unit 3 M3-EV-04-0032 Rev 0 January 4, 2005 Total num 7 of pages: 5 Graham Rossan<'7 kA Z41A..

-'I Preparer P

Joon Cho,,

Independent Re'view290" Joe Green Engineering Approve V/

1/4/05 Date 1/4/05 Date 1/4/05 Date

Millstone Unit 3 Technical Evaluation: M3-EV-04-0032, Revision 0 Sump pH Impact Review for RSS Pump Start on RWST Low-Low Level

1.

PURPOSE The purpose of this technical evaluation is to determine the impact of the delayed Recirculation Spray System (RSS) pump start signal on the containment sump pH control (Ref. 4). This evaluation incorporates the proposed RSS pump start signal at or near the RWST low-low level in response to NRC Generic Safety Issue (GSI) 191 (Refs. 2 and 3).

The following key items regarding the containment sump pH control are investigated in this technical evaluation. They are:

" Trisodium Phosphate (TSP) Requirement

" Sump pH Requirement at the RSS Initiation

" Maximum RSS pH for Material Compatibility

" Ultimate Sump Iodine Partition Coefficients (H) and Decontamination Factor (DF)

" Maximum Sump pH for a Small Break LOCA (SBLOCA) without Containment Depressurization Actuation (CDA)

2. BACKGROUND The proposed RSS pump start signal time at or near the RWST tank low-low level (i.e., approximately 520,000 gallons remaining in the RWST) (Refs. 2 and 3) will maximize water level on the containment floor to ensure that the containment emergency sump is covered when the RSS pumps start.

Since several input parameters employed in Ref. 4 are revised due to the delayed start of the RSS pumps, the impact assessment of the revised input parameters to Ref. 4 is performed.

3. REFERENCES

1.

S & W Calculation 12179-US(B)-273, Rev. 7, "Containment Pressure and Temperature Analysis Following a LOCA".

2.

Engineering Record Correspondence Number, 25212-ER-04-0034, Transmittal of Design Input to Support Containment Reanalysis - RSS Pump Start on RWST Low-Low Level Signal.

3.

Design Change Record Number, M3-04004, Change RSS Pump Start Signal from Timer to Start on RWST Low-Low Level Signal.

4.

S & W Calculation 12179-US(B)-350, Rev. 2 (including CCN 01 & 02), "Trisodium Phosphate System for Sump pH Control".

Page 2 of 5

Millstone Unit 3 Technical Evaluation: M3-EV-04-0032, Revision 0 Sump pH Impact Review for RSS Pump Start on RWST Low-Low Level

5.

CR M3-99-3916, NRC Identified URI 50-423/99-10-01 Discrepancies in Calculation for MP3 Containment Sump Trisodium Phosphate Concentration.

6.

NUREG-0800, SRP Section 6.5.2, "Containment Spray as a Fission Product Cleanup System",

Rev. 2, December 1988.

7.

S & W Calculation 108788-US(B)-372, Rev. 0, "Simplified Containment Recirculation Spray System (RSS) NPSH and Suction Hydraulic Analysis Without Debris Transport".

8.

S & W Calculation 03705-US(B)-352, Rev. 1, "Containment Pressure and Temperature Response for Piping Thermal Analysis".

4. DISCUSSION As described in Section 1, the key items regarding the containment sump pH control are evaluated as follows:

Trisodium Phosphate (TSP) Requirement Ref. 4 calculated the TSP volume required to ensure minimum ultimate sump pH of 7.1. All input parameters employed to calculate the required TSP volume are not affected by the proposed RSS pump start signal delay. Therefore, the TSP requirement remains unchanged.

Sump pH Reguirement at the RSS Initiation The sump pH should be above 7 by the onset of the RSS initiation (Ref. 6). Ref. 4 calculated the sump pH at the RSS initiation as 7.29. The RSS initiation time is delayed due to the proposed RSS pump start signal. The revised minimum water level on the containment floor at the RSS initiation is calculated as 52" above EL-24'-6" (Ref. 7) which is higher than the top elevation of TSP basket (i.e., 39" above EL-24'-6":Ref. 4). Therefore, the sump pH at the RSS initiation is at least equal or greater than the minimum ultimate sump pH of 7. 1.

Maximum RSS pH for Material Compatibility The short term localized sump high pH conditions at the RSS initiation may affect the material compatibility. Since all TSP baskets are fully submerged at the RSS initiation, as discussed above, and since the mixing of the TSP with the sump water is enhanced by the extended Quench Spray System (QSS) operation prior to the RSS initiation, the localized sump high pH conditions will be improved by the proposed RSS pump start signal delay.

Ultimate Sump Iodine Partition Coefficients (H) and Decontamination Factor (DF)

Ref. 4 calculated the ultimate (at 30 days) sump iodine partition coefficients and decontamination factor conservatively assuming that the maximum sump pH is 7 and the sump water temperature of 250TF.

Since the revised sump water temperature calculated in Ref. 8 is still bounded by conservative 250T, the ultimate sump H and DF remain unchanged.

Page 3 of 5

Millstone Unit 3 Technical Evaluation: M3-EV-04-0032, Revision 0 Sump pH Impact Review for RSS Pump Start on RWST Low-Low Level Maximum Sump pH for a Small Break LOCA (SBLOCA) without Containment Depressurization Actuation (CDA)

Ref. 4 calculated the ultimate maximum sump pH in the event of a SBLOCA without CDA as less than 8.2 based on the current mass of TSP stored in the containment. Since no CDA is assumed for a SBLOCA scenario, the ultimate sump pH is not affected by the proposed RSS pump start signal delay.

5. SAFETY SIGNIFICANCE The 10CFR50.59 screen for this Technical Evaluation is being performed by the parent process (Ref. 3).

6. CONCLUSION The impact of the delayed Recirculation Spray System (RSS) pump start signal on the containment sump pH control is minimal and Ref. 4 results remain valid.

7. ATTACHMENTS - Independent Reviewer's Comments, Dated 1/4/05 Page 4 of 5

Approved 8/27/02 f

Effective 8/30/02 ATTACHMENT I Independent Reviewer Comment and Resolution Sheet(s)

(ER/EV) No.

M3-EV-04-0032 Page 1

of I

Date 1/4/05 Independent Reviewer:

Joon Cho Comment No.__ ERIEV Section I Comment I

4,6 Overall impact of the delayed RSS pump start signal on the sump pH control is considered to be beneficial mainly due to full submergence of the TSP baskets on the containment floor in conjunction with the extended OSS actuation time prior to the RSS initiation which minimize the localized sump pH.

MP-03-DCC-FAP 1.4-001 Rev. 000 Page 5 of 5

ML062050057

Text

Reference:

Q at 111:1

Navigation menu

Search