ML20101K746

COL Docs - FW: Vogtle 3&4 LAR Pre-Submittal Meeting Request

ML20101K746
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Issue date:	04/10/2020
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Rankin, Jennivine Sent:

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Vogtle PEmails

Subject:

FW: RE: Vogtle 3&4 LAR Pre-Submittal Meeting Request Attachments:

LAR-20-004_PSM_Draft_NRC.pdf SNC draft LAR 20-004 to support public meeting on 4/23.

From: Henderson, Ryan Donald <RDHENDER@SOUTHERNCO.COM>

Sent: Thursday, April 09, 2020 3:28 PM To: Rankin, Jennivine <Jennivine.Rankin@nrc.gov>

Cc: Arafeh, Yasmeen N. <YNARAFEH@southernco.com>; Humphrey, Mark Phillips

<MPHUMPHR@southernco.com>; Santos, Cayetano <Cayetano.Santos@nrc.gov>

Subject:

[External_Sender] RE: Vogtle 3&4 LAR Pre-Submittal Meeting Request

Jennie, See attached for the draft LAR in preparation for the Pre-Submittal Meeting on 4/23. Assuming the comments from the staff are manageable, we intend to submit the LAR by 4/30.

Thanks, Ryan Henderson Licensing Office: 205-992-6426 Cell: 205-613-0342

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FW: RE: Vogtle 3&4 LAR Pre-Submittal Meeting Request Sent Date:

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Southern Nuclear Operating Company ND-20-XXXX Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Request for License Amendment:

Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

(This Enclosure consists of 17 pages, including this cover page)

DRAFT rating Plant (VEGP) Units 3 and 4 P) Units Request for License Amendment License Amendment:

e Makeup Tank Boron e Makeup Tank Boron Concentration Re Conce (LAR-20 20-004 0

)

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 2 of 17 Table of Contents 1.

SUMMARY

DESCRIPTION 2.

DETAILED DESCRIPTION 3.

TECHNICAL EVALUATION 4.

REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 Significant Hazards Consideration Determination 4.4 Conclusions 5.

ENVIRONMENTAL CONSIDERATIONS 6.

REFRENCES DRAFT etermination termin TIONS

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 3 of 17 Pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC, or the Licensee) hereby requests an amendment to Combined License (COL)

Nos. NPF-91 and NPF-92 for Vogtle Electric Generating Plant (VEGP) Units 3 and 4, respectively.

1.

SUMMARY

DESCRIPTION The requested amendment proposes changes to the upper limit of the Core Makeup Tank (CMT) boron concentration Technical Specification (TS) Surveillance Requirement (SR), the mass of trisodium phosphate (TSP) required by TS Limiting Condition for Operation (LCO) and associated SR, and the frequency of performance of the CMT boron concentration TS SR.

The requested amendment proposes changes to the licensing basis documents in the form of departures from the plant-specific Design Control Document (DCD) Tier 2 information (as incorporated into the UFSAR), and involves changes to the plant-specific TS (COL Appendix A). This enclosure requests approval of the license amendment necessary to implement the changes.

2.

DETAILED DESCRIPTION As described in the UFSAR, the Passive Core Cooling System (PXS) performs the primary function to provide emergency core cooling following postulated design basis events. PXS is a safety-related system and consists of two CMTs, two accumulators, the in-containment refueling water storage tank (IRWST), the passive residual heat removal heat exchanger, pH adjustment baskets, and associated piping, valves, instrumentation, and other related equipment.

The CMTs provide Reactor Coolant System (RCS) makeup and boration during events not involving loss of coolant when the normal makeup system is unavailable or insufficient. The two CMTs are located inside the containment at an elevation slightly above the reactor coolant loops. During normal operation, the CMTs are completely full of cold, borated water. The boration capability of these tanks provides adequate core shutdown margin following a steam line break.

The CMTs are connected to the RCS through a discharge injection line and an inlet pressure balance line connected to a cold leg. The discharge line is blocked by two normally closed, parallel air-operated isolation valves that open on a loss of air pressure or electrical power, or on control signal actuation.

The pressure balance line from the cold leg is normally open to maintain the CMTs at RCS pressure, which prevents water hammer upon initiation of CMT injection.

The cold leg pressure balance line is connected to the top of the cold leg and is routed continuously upward to the high point near the CMT inlet. The normal water temperature in this line will be hotter than the discharge line.

The outlet line from the bottom of each CMT provides an injection path to one of the two direct vessel injection lines, which are connected to the reactor vessel downcomer annulus. Upon receipt of a safeguards actuation signal, the two parallel valves in each discharge line open to align the associated CMT to the RCS.

DRAFT Lice Lice d 4, respe d 4, res of the Core Makeup Tank of the Core Ma lance Requ ance R irement rement (SR), the Condition Condit for Operation (LCO) eration the CMT boron concentration TS the CMT boron concentration he licensing basis documents in the form he licensing basis documents in the form ntrol Document (DCD) Tier 2 information (as ntrol Document (DCD) Tier 2 information (as es changes to the changes to the plant pla

-specific TS (C proval of the license amendment necess f the license am he Passive Core Cooling System (PXS) pe assive Core Cooling System (PXS) p cy core cooling following postulated design ooling following postulated design nd consists of of two tw CMTTs, two accumulat

, two accumul tank (IRWST), the passive residual heat re he passive residual heat re and associated piping, valves, instrum and associated piping, valv rovide Reactor Coolant System (RCS) mak rovide Reactor Coolant System (RC oss of coolant when the normal makeup sy oss of coolant when the normal makeup Tss are located inside the containment at an e are located inside the containment at an e

. During normal operation, the CMTs ing normal operation, the CMTs are are ration capability of these tanks provides ade ability of these tanks provides ade ine break.

The CMTs are connected to the RCS t The CMTs are connected to balance line ne connected to a cold le connected to a co parallel air-operated isolation valv perated isolation val on control signal actuation.

al actu The pressure balance line lanc pressure, which preven pressure, which prev The cold leg pres The cold leg pres ntinuously up ntinuously up ne will b ne will b

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 4 of 17 There are two operating processes for the CMTs, steam-compensated injection and water recirculation. During steam-compensated injection, steam is supplied to the CMTs to displace the water that is injected into the RCS. This steam is provided to the CMTs through the cold leg pressure balance line. The cold leg line only has steam flow if the cold legs are voided.

During water recirculation, hot water from the cold leg enters the CMTs, and the cold water in the tank is discharged to the RCS. This results in RCS boration and a net increase in RCS mass.

The operating process for the CMTs depends on conditions in the RCS, primarily voiding in the cold leg. When the cold leg is full of water, the cold leg pressure balance line remains full of water and the injection occurs via water recirculation. If RCS inventory decreases sufficiently to cause cold leg voiding, then steam flows through the cold leg balance lines to the CMTs.

Also, the CMTs provide passive safety injection during loss of coolant accidents at a relatively high flow for a longer duration than the accumulators. During a loss of coolant accident, they provide injection rates commensurate with the severity of the loss of coolant accident.

For a larger loss of coolant accident, and after the automatic depressurization system has been actuated, the cold legs are expected to be voided. In this situation, the CMTs operate at their maximum injection rate with steam entering the CMTs through the cold leg pressure balance lines.

For smaller loss of coolant accidents the CMTs initially operate in the water recirculation mode since the cold legs are water filled. During this water recirculation, the CMTs remain full, but the cold, borated water is purged with hot, less borated cold leg water. The water recirculation provides RCS makeup and also effectively borates the RCS. As the accident progresses, when the cold legs void, the CMTs switch to the steam displacement mode which provides higher flow rates.

Connections are provided for remotely adjusting the boron concentration of the borated water in each CMT during normal plant operation, as required. Makeup water for the CMT is provided by the Chemical and Volume Control System (CVS). Samples from the CMTs are taken periodically to check boron concentration.

Control of the pH in the containment sump water post-accident is achieved through the use of pH adjustment baskets containing granulated TSP. The baskets are located below the minimum post-accident floodup level, and chemical addition is initiated passively when the water reaches the baskets. The baskets are placed at least a foot above the floor to reduce the chance that water spills in containment will dissolve the TSP.

The TSP is designed to maintain the pH of the containment sump water in a range from 7.0 to 9.5. The chemistry reduces radiolytic formation of elemental iodine in the containment sump, consequently reducing the aqueous production of organic iodine, and ultimately reducing the airborne iodine in containment and offsite doses.

The chemical addition also helps to reduce the potential for stress corrosion cracking of stainless steel components in a post floodup condition, where chlorides can leach out of the Ts t Ts t through t through legs are voide legs ar Ts, and the cold water in Ts, and the and a net increase in RCS and a net increa ns in th ns in the RCS, primarily voiding in y voidin eg pressure balance line remains full eg pressure balance line remains fu culation. If RCS inventory decreases culation. If RCS inventory decreases ows through the cold leg balance lines to ows through the cold leg balance lines to tion during loss of coolant accidents at a rela ng loss of coolan ccumulators. During a loss of coolant accid During a los with the severity of the loss of coolant accid f the loss dent, and after the automatic depressuriza ent, and after the automatic depres e expected to be voided. In this situation, th ected to be voided. In this situation, e with steam entering the CMTs through t eam entering the CMTs through t oolant accidents the CMTs initially operate in olant accidents the CMTs initia s are water filled. Dur s are water fille ing this water recircula g this w d water is purged with hot, less borated cold d water is purged with hot, less bo S makeup and also effectively borates the S makeup and also effectively bora cold leg cold legs void, the CMTs switch to the stea e CMTs switch to the s low rates.

ow rates nnections are provided for remotely adjustin are provided for remotely adjustin in each CMT during normal plant operati each CMT during nor provided by the Chemical and Volume C provided by the Chemical taken periodically to check boron conc taken periodically to check bo Control of the pH in the containm e pH in the containm of pH adjustment baske ent ba ts con con minimum post-accident floo ccide water reaches the basket water reaches the ba the chanc the e that water s t wate The TSP is design The TSP is design 9.5. The che 9.5. The che p, conse p, conse g t g t

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 5 of 17 containment concrete and potentially affect these components during a long-term floodup event.

LCO 3.6.8, pH Adjustment, requires the pH adjustment baskets contain 25,920 lbs of TSP.

SRs exist to verify this and to verify that a sample of the TSP in the pH adjustment baskets provides adequate pH adjustment of the post-accident water.

Two sample lines, one in the upper head and the other in the lower head, are provided for sampling the solution in the core makeup tank. A fill connection is provided for core makeup tank make up water from the chemical and volume control system.

Prior to the collection of liquid samples either in the laboratory or in the grab sampling unit, the lines are purged with source liquid to provide representative samples. The purging flow returns to the effluent holdup tank of the liquid radwaste system.

LCO 3.5.2, CMTs - Operating, requires both CMTs to be operable. One of the SRs exists to verify the boron concentration in each CMT is 3400 ppm and 3700 ppm. LCO 3.5.3, CMTs

- Shutdown, Reactor Coolant System (RCS) Intact, requires one CMT to be operable, with the same SR applicable to the required CMT. The SR Frequency is 7 days.

Because the CMT is in open communication with the RCS via the balance line, whenever the surveillance is performed, the volume removed is replaced by water via the balance line. The RCS water is typically at a lower boron concentration; therefore, each sample dilutes the CMT.

Depending on the starting boron concentration, there is the possibility that this sampling activity could cause the CMT boron concentration to fall to a point which would require borated makeup. Borated makeup at power is not desirable because it forces the displaced water back into the RCS via the balance line. This causes additional thermal transients on the balance line and also causes the potential for a reactivity excursion in the reactor if the boron concentration of the RCS is affected.

The proposed solution to mitigate these issues is to raise the upper boron concentration limit permitted for the CMT, extend the frequency of the CMT boron concentration surveillance, and to increase the mass of TSP required for the pH adjustment baskets.

Licensing Basis Change Descriptions:

COL Appendix A, Technical Specifications Changes x

SR 3.5.2.4 maximum boron concentration is revised from 3700 ppm to 4500 ppm x

SR 3.5.2.4 frequency is revised from 7 days to 31 days x

LCO 3.6.8 and SR 3.6.8.1 required TSP is revised from 25,920 lbs to 26,460 lbs UFSAR Changes x

UFSAR Subsection 6.3.2.2.4 required TSP is revised from at least 25,920 pounds to at least 26,460 pounds DRAFT 25,920 lbs of 25,920 H adjustment bask H adjust lower head, are provided for ower head, are pro on is provided for core makeup on is provided for core m system.

system aboratory or in the grab sampling unit, aboratory or in the grab sampling unit, representative samples. The purging flow representative samples. The purging flow dwaste system.

dwaste h CMTs to be operable. One of the SRs ex to be operable. O T is 3400 ppm and ppm and 3700 ppm. LCO 3.5.

37 (RCS) Intact, requires one CMT to be ope uires on red CMT.

red CM The SR Frequency is 7 days.

uency is ommunication with unication with the RCS the R via the balance e balan e volume removed is replaced by water via e removed is replaced by water via lower boron concentration; therefore, each s concentration; therefore, eac tartin arting boron concentration, there is the p g boron concentration, there is the p e the CMT boron concentration to fall e the CMT boron concentration to a po d makeup at power is not desirable because d makeup at power is not desirab via the balance line. This causes additiona via the balance line. This causes a also causes the potential for a reactivity also causes the potential for a reactiv ration of the RCS is affected.

ation of the RCS is affected.

e proposed solution to mitigate the d solution to mitigate these issues se issues permitted for the CMT, extend the frequen e CMT, e and to increase the mass of TSP and to increase the mass required Licensing Basis Change Description Licensing Basis Change Descr DR COL Appendix A, dix A, Technical S Technical S D

x SR 3.5.2.4 4 maximu x

SR 3.5.2.4 fre 5.2.4 fr x

LCO 3.6 LCO 3.6 AR C AR C D

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 6 of 17 x

UFSAR Subsection 9.3.6.2.6 upper boron concentration of the CVS ability for borated makeup is revised to reflect that the 4375 ppm value is a nominal value Conforming changes to the Technical Specification Bases are identified for the Technical Specifications changes. The changes will be made under the Technical Specification Bases Control Program upon approval of the amendment and markups are provided for information only with this application.

3.

TECHNICAL EVALUATION Calculations were performed to provide validation that raising the upper limit of the CMT boron concentration to 4500 ppm resulting in the maximum amount of post-accident boron concentration of 3050 ppm is acceptable with respect to long term containment pH and boron concentration. The pH adjustment calculations were revised to use a more conservative maximum CMT water volume, which results in the maximum post-accident containment water volume being revised from 867,308 gallons to 867,830 gallons. The calculations resulted in a change to the minimum measured TSP volume from 480 ft3 to 490 ft3 to provide proper buffering of post-accident water.

The containment flood-up water sources and the available TSP have been analyzed to calculate a post-loss of coolant accident (LOCA) pH value. The goal of the calculation is to confirm that the pH is above 7.0 within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of an event. The results of the calculation yield a minimum pH (utilizing the minimum required TSP) of 7.23 when CMT boron concentration is 4500 ppm, which corresponds to a containment flood-up boron concentration of 3050 ppm.

Post-accident boron concentration calculations confirm two things: that there is adequate shutdown margin and that the maximum boron concentration for the Reactor Vessel, the Containment, and the IRWST does not cause boron to come out of solution. Boron does not come out of solution due to high concentrations (i.e. will not go above the solubility limit). The increase in maximum CMT boron concentration from 3700 ppm to 4500 ppm decreases the amount of margin with respect to solubility limits. The reduction in margin is a minimal percentage. The margin to the solubility limit (35,000 ppm) for containment in the evaluation of maximum reactor vessel boron concentration went from 29,387 ppm to 29,339 ppm and for the evaluation of maximum IRWST concentration it went from 26,043 ppm to 26,007 ppm.

Therefore, the increase in the maximum CMT boron concentration with this magnitude has little effect on the minimum overall margin to the solubility limit due to the significant margin which exists.

The equipment qualification program previously evaluated 4375 ppm for the CVS and equipment that could be subjected to the 4375 ppm of the CVS (including the CMTs). An increase to 4500 ppm does not significantly impact the conclusions of the existing analyses.

The increase in concentration represents a 0.01 weight percent increase, and a 0.01 pH decrease (making the pH more acidic). These differences are negligible for the materials subjected to the increase in boron concentration.

The non-LOCA safety analyses typically model minimum CMT boron concentration for applications considering minimum safeguards and maximum CMT boron concentration for applications considering maximum safeguards. Since the time frame of interest for applications considering maximum safeguards is after a reactor trip, these analyses are not DRAFT for the Tec for the al Specification Bas al Speci provided for information provided fo sing the upper limit of the CMT boron sing the upper limit of the CMT boro mum amount of post mum a

-accident boron boron ect to long term containment pH and boron ect to long term containment pH and boron were revised to use a more conserv were revised to use a ativ the maximum post maximum post-accident containment w accid to 867,830 gallons. The calculations resulte 30 gallons. The P volume from 480 ft 480 ft3 to 490 ft to 3 to provid r sources and the available TSP have be sources and the available TSP h nt accident (LOCA) pH value. The goal of t dent (LOCA) pH value. The goal of 7.0 within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of an event. The results o n 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of an event. The results o he minimum required TSP) of 7.23 when C required TSP) of 7.23 when rresponds to a containment ntainment flood-up boron c boron c on con on concentration calculations confirm two centration calculations gin and that the maximum boron concentr gin and that the maximum boron

, and the

, and th IRWST does not cause boron to c T does not cause bo of solu of solution due to high tion due to high concentrations (i.e. w concentrations (i.e e in maximum CMT boron in maximum CMT boron concentration fro concentration fro unt of margin with respect to solubility margin with respect to solubility lim lim ercentage. The margin to the solubility limit The margin to the solubility limit of maximum reactor vessel boron concentra f maximum reactor vess the evaluation of maximum IRWST con the evaluation of maximum Therefore, the increase in the maxim Therefore, the increase in the little effect on the minimum overall on the minimum ove which exists.

The equipment qualificatio qua equipment that e

could be could increase to 4500 ppm increase to 4500 ppm The increase in co The increase in co decrease (makin decrease (makin jected to th jected to th

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 7 of 17 sensitive to increases in the maximum CMT boron concentration. For cases where nominal safeguards are modeled, the increase in the CMT boron concentration would be a benefit or have no impact. Therefore, the proposed change is acceptable with respect to the non-LOCA safety analyses.

COL Appendix A, Technical Specification 3.5.2 is proposed to be revised to identify the maximum CMT boron concentration of 4500 ppm. The maximum boron concentration allowed within each CMT at any time shall be 4500 ppm to prevent overboration.

The boron concentration inside the CMTs is required to be maintained to support safety analysis initial conditions. To confirm that the CMTs have adequate boron concentration, they are periodically sampled based on the Technical Specification 3.5.2 Surveillance Requirements. Leakage from the CMT can lead to RCS water (at a lower boron concentration) entering the CMT and reducing the total available boron in the CMT. If leakage is occurring, sampling will identify the reduced boron concentration.

Due to the arrangement of the CMTs (see UFSAR Figure 6.3-1 Sheet 1), the act of sampling the CMTs also creates in-leakage from the RCS to the tank and reduces the boron concentration. To minimize the effect of sampling on CMT boron concentration, a longer time between sampling is proposed. This proposed change is to reduce the frequency from 7 days to 31 days which is consistent with the sampling frequency of the Accumulators and the In-Containment Refueling Water Storage Tank (IRWST). This change in sampling frequency is acceptable as it can be demonstrated that at low, undetectable leakage rates, the boron concentration in the CMT can continue to meet the minimum 3400 ppm requirement for 31 days.

Boron dilution predictions have been performed to evaluate the time the CMT average boron concentration will reach 3400 ppm for different leak rates with an initial nominal CMT boron concentration of approximately 4375 ppm and the conservative assumption that the RCS water coming into the CMT when the leak exists is pure water (i.e., RCS water diluted to 0 ppm boron). This is conservative because a realistic RCS boron concentration is approximately 500 ppm and would therefore result in less dilution of the CMT boron concentration due to in-leakage. At a leakage rate of 0.125 gpm, the CMT average boron concentration remains at or above 3400 ppm for approximately 23 days. At lower leakage rates, such as 0.062 gpm, the CMT average boron concentration remains at or above 3400 ppm for approximately 46 days.

At a leakage rate of approximately 0.1 gpm, the CMT average boron concentration will remain at or above 3400 ppm for 29 days.

One justification for reducing sample frequency is that there are other indicators that can identify RCS leakage into the CMT. An additional method to detect in-leakage from the RCS to the CMTs is to monitor the CMT temperature at the top of the tank since any leakage into the CMT results in water being pulled into the top of the tank through the normally open balance line. There are two non-safety-related (Safety Class E) thermowell mounted temperature elements at the top of each CMT near the inlet nozzle which will alarm if the temperature exceeds the setpoint of 107.5°F (this setpoint plus uncertainty is the 120°F CMT top high temperature alarm which has indication in the Main Control Room used for SR 3.5.2.1). There are CMT leakage levels that are detectable, as demonstrated by the time period it takes for the high temperature alarm to be reached from the steady state CMT temperature due to in-leakage, and therefore can indicate a potential reduction in the CMT DRAFT e a e a o the non o the n revised to identify the revised t oron concentration allowed oron concentrat boration.

boration be maintained to support safety be maintained to support sa e adequate boron concentration, they e adequate boron concentration, the ca cal Specification 3.5.2 Surveillance l Specification 3.5.2 Surveillance RCS water (at a lower boron concentration)

RCS water (at a lower boron concentration) le boron in the CMT. If leakage is occurring e boron in the CMT. If l entration.

ation.

e UFSAR Figure 6.3 ure 6.3-1 Sheet 1) 1 S

, the act of s from the RCS to the tank and reduces the ta ct of sampling on CMT ct of sam boron concen oron co tration his proposed change is to reduce s proposed change is to reduce the freque the t with the sampling frequency of the sampling freque the Accum he Accu er Storage Tank e Tan (IRWST). This change in WST). This change in demonstrated that at low, undetectable le d that at low, undetectable MT can continue to meet the minimum 340 to meet the minimum 340 predictions hav predictions have been performed to evaluat e been performed n will reach 3400 ppm for different leak rat n will reach 3400 ppm for different le tion of approximately 4375 ppm and the c tion of approximately 4375 ppm and the oming ming into int the CMT when the leak exists is p T when the leak exists is p n). This is conservative because a s is conservative because a realistic realistic 00 ppm and would therefore result in less dil would therefore result in less dil leakage. At a le eakage. A akage rate of 0.125 gpm, th akage rat above 3400 ppm for approximately 23 d above 3400 ppm for appro CMT average boron concentration rem CMT average boron concentr At a leakage rate of approximately 0 e rate of approximate at or above 3400 ppm for 29 day 400 ppm for 29 day One justification for reduci for identify RCS id leakage into kage to the CMTs is to to the CMTs is to mon mo the CMT results in the CMT results in alance line. Th alance line. Th perature e perature e rature rature

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 8 of 17 boron concentration before the surveillance frequency of 31 days if these higher leakage rates are occurring.

An analysis has been performed to evaluate small in-flow which would be indicative of leakage from within the CMT. A range of leakage rates were evaluated to determine a detectable level of leakage by the rate of the change in CMT temperature. A Computational Fluid Dynamics (CFD) model, originally developed to evaluate flow out of the CMT inlet when makeup was added was modified to evaluate a small leak causing an in-flow of water into the CMT from the balance line. A leakage rate of 0.125 gpm was analyzed to demonstrate how rapidly the temperature of the tank increases to the alarm setpoint at the CMT temperature elements at the top of the tank. These sensors are located on either side of the inlet nozzle and approximately 20 inches over the center line of the tank and 5 inches down. At a leakage rate of 0.125 gpm, this analysis indicates the temperature increase from 100°F to 107.5°F occurs within approximately 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />. For a leakage rate of 0.25 gpm, a temperature increase from 100°F to 120°F occurs within approximately 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

In order to address uncertainties in the CFD modeling, several conservatisms were applied to the CFD results as transient time multipliers. These applied conservatisms increase the time it takes the in-leakage to increase the CMT temperature. The expected CMT temperature change will likely be greater than the temperature change from 100°F to 107.5°F that was modelled; however, this has been addressed by the conservatisms applied to the CFD results.

The CMT temperatures used in the modeling is representative of Mode 1, steady state conditions; however, in Modes 2 and 3 the CMT temperature will experience similar temperature increase due to in-leakage. During Modes 4 and 5, the lower pressure of the RCS will limit the potential for leakage.

Based on the CFD modeling with additional conservatisms, it is predicted that at leakage rates as low as approximately 0.1 gpm, the alarm response to the top CMT temperature would occur within 20 days, and therefore the CMT top temperature would detect leakages of this flow rate and higher within a surveillance frequency of 31 days. At a leakage rate of approximately 0.1 gpm, and performing a boron dilution analysis starting at a CMT boron concentration of 4375 ppm and RCS concentration of 0 ppm, the CMT remains above 3400 ppm for approximately 28 days and therefore the CMT temperature alarm would indicate the leakage in advance of the CMT concentration dropping below 3400 ppm. At higher leakage rates, the high temperature alarm will be reached much sooner. For example, at a leakage rate of 0.2 gpm the leakage would be indicated by 6 days and per the boron dilution analysis, the CMT boron concentration reaches 3400 ppm at approximately 14 days. At a leakage rate of 0.125 gpm, the leakage would be indicated by approximately 14 days and, the CMT boron concentration reaches 3400 ppm at approximately 23 days. These cases demonstrate there is margin between the time that the CMT high temperature indicates leakage and the CMT boron concentration is reduced to 3400 ppm.

By comparison of the calculated allowable leakage time from the boron dilution analysis cases and the time calculated by the CFD model with conservatisms to detect the CMT leakage as indicated by reaching the CMT top temperature alarm, CMT sampling could be conducted at a frequency of 42 days and the CMT boron concentration would remain at or above 3400 ppm.

Since the sampled boron concentration is expected to drop over the fuel cycle, either due to sampling itself or due to very small leaks in the CMT, the starting concentration may not DRAFT dicative of lea dicative ine a detectable le ine a de tati tational Fluid Dynamics onal Fl T inlet when makeup was T inlet when m w of water into the CMT from of water into the C to demonstrate how rapidly the to demonstrate how rapid the CMT temperature elements at the CMT temperature elements either side of the either s inlet nozzle and zzle an nk and 5 nk and 5 inches down. At a leakagee rate rate ure increase from 100°F to 107.5°F occurs ure increase from 100°F to 107.5°F occurs e of 0.25 gpm, a temperature increase from e of 0.25 gpm, a tempe 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

rs.

FD modeling, several conservatisms were a several co tipliers. These applied tipliers. These applied conservatisms increa cons the CMT tempera the CMT ture. The The expected CMT exp n the temperature change from 100°F to the temperature change from 100° 1

een addressed by the conservatisms applied dressed by the conservatisms applie sed in the modelin mod g is representative of M is representative of M Modes 2 and 3 the CMT temperature nd 3 the CMT temperature due to in-leakage. During Modes 4 and 5

e. During Modes 4 and 5 otential otential for leakage.

for le CFD modeling with additional conservatisms CFD modeling with additional conse proximately 0.1 gpm, the alarm response to proximately 0.1 gpm, the alarm respon days, and therefore the CMT top temperatur days, and therefore the CMT top temperat gher within a surveillance frequency of 31 da er within a surveillance frequency of 31 da

, and performing a boron dilution analysis s erforming a boron dilution analysis s pm and RCS concentration of 0 ppm, the C concentration of 0 ppm, the C 28 days and therefore the 28 days and therefore th CMT temperatu the CMT concentration dropping the CMT concentration d belo temperature alarm will be reached m temperature alarm will be rea the leakage would be indicated by would be indicated b concentration reaches 3400 ppm reaches 3400 ppm the leakage would be indicate uld be reaches 3400 ppm at app pm a between the time that between the time th concentration is reduc concentration is redu y comparison o y comparison o the time c the time c ed by ed by

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 9 of 17 always be as high as the 4375 ppm initial concentration used in the boron dilution analysis cases. Based on the predictions for identifiable leakage, the starting CMT concentration could be as low as 4184 ppm boron concentration, conservatively assuming 0 ppm RCS boron concentration in-leakage, and still ensure that unacceptable leakage is identified prior to the CMT violating the 3400 ppm boron concentration limit with a 31 day sampling frequency.

Therefore, the CMT top high temperature alarm can indicate to the operators that there may be in-leakage and to initiate by procedure steps to identify if the CMT boron concentration remains within the required limits. If the temperature or boron concentration is outside acceptable limits, TS 3.5.2 Required Action B.1 or C.1 would be performed to restore the temperature and boron concentration in the affected CMT(s).

Therefore, a sampling frequency of 31 days will adequately demonstrate that the CMT boron concentration has been maintained within the required limits. Leakage at a rate which could lead to a boron concentration less than 3400 ppm within 31 days will be indicated by the CMT high temperature alarm.

COL Appendix A, Technical Specification 3.5.2, is proposed to revise the frequency of surveillance of the CMT boron concentration to 31 days. The 31 day verification frequency of the boron concentration is adequate to identify changes which could occur from mechanisms such as in-leakage considering the provisions for monitoring temperature of the inlet line and top of the CMT. Additionally, the top of the CMT has control room indication and an alarm on increased temperature, which would be indicative of in-leakage.

UFSAR Subsection 9.3.6.2.6 states that borated makeup can be varied from 0 to 4375 ppm (2.5 weight present) by taking suction from both the boric acid storage tank and the demineralized water tank. This section is revised to clarify that 4375 ppm is a nominal value.

The maximum value is not added here since the maximum is provided as margin to the nominal value and not intended to be the normal operating concentration.

The total containment boron concentration is derived by calculating the total boron mass concentration provided by various systems and components and then dividing this value by the mass of the water. The TSP concentration required to obtain a pH of 7.0 is derived using the boron concentration plus margin for other acids. The required TSP value is then calculated using the TSP concentration and the total containment water volume. As a result, increasing the maximum boron concentration results in a TSP value of 26,460 lbs. Therefore, COL Appendix A, Technical Specification 3.6.8 is proposed to be revised to increase the TSP value from 25,920 lbs to 26,460 lbs. This value is consistent with the minimum effective TSP required by analysis to bring the post-accident containment flood-up water to a pH of 7.0 in the required time frame. The function of the PXS and containment pH control is not adversely impacted. The Applicable MODES and Actions are not changed.

This required TSP mass value supports the design basis accident (DBA) releases of iodine into containment such that the pH of the containment sump is adjusted to enhance the retention of the iodine.

A TSP volume of 490 ft3 corresponds to the TSP mass value of 26,460 lbs. The initial loading value for the TSP volume of 560 ft3 contains an additional 14% margin, which was previously 15%. This initial loading TSP volume corresponds to a TSP value of 30,240 lbs, which also DRAFT entra entra ppm RCS ppm RC entified prior t entified mpling frequency.

mpling f e

e operators that there may perators that he CMT boron concentration e CMT boron conce boron concentration is outside boron concentration is o would be performed to restore the would be performed to restore MT(s).

MT(s).

equately demonstrate that the CMT boron equately demonstrate that the CMT boron equired limits. Leakage at a rate which coul quired limits. Leakage a ppm within 31 days will be indicated by the C within 31 days will be cation 3.5.2, is proposed to revise the fre oposed entration to 31 days.

entration The 31 day verification e 31 day ate to identify changes which could occur fr e to identify changes which could o g the provisions for monitoring temperatur provisions for monitoring temperature

, the top of the CMT has control room indic of the CMT has control room indic which would bee indicative of in indicative of in-leakage.

leakage.

9.3.6.2.6 states that borated makeup can b 9.3.6.2.6 states that borated m ent) by taking suction from both the bo ent) by taking suction from b water tank. This water tank. This section is revised to clarify section is revised m value is not added here m value is not adde since the max nce th alue and not intended to be the normal alue and not intended to be the normal ope op total containment boron concentration is d containment boron concentration is d ncentration provided by various systems a provided by various systems a the mass of the water.

mass of the water. The TSP concentrat Th the boron concentration plus the boron concentration plu margin for o using the TSP concentration and the using the TSP concentration the maximum boron concentration um boron concentra Appendix A, Technical Specificat Technical Specificat from 25,920 lbs to 26,460 lb s to 26,460 lb required by analysis to brin ysis the required time frame.

the required time fram impacted. The imp Applica Applic Th Thisis required TS required TS o containme o containme ion of ion of

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 10 of 17 includes the 14% margin. This total TSP mass value (TSP mass + margin) accounts for degradation of the TSP during normal operation. The 1% reduction in margin over the original margin continues to satisfy the minimum pH requirement, even with an allowance for degradation of the TSP, and therefore is acceptable from a degradation standpoint. The TSP assumed density is not changed.

Associated with Surveillance Requirement 3.6.8.2 is a revision of the testing sample size from 2.14 grams at 480 ft3 and 2.41 grams at 560 ft3 to 2.19 grams at 490 ft3 and 2.49 grams at 560 ft3. While the revised volume of 490 ft3 corresponds to 26,460 lbs when accounting for other acid sources, beyond boron, that buildup over time post-accident, this test is simplified and does not include the other acids produced post-accident. When only considering boron acid sources in the test, the minimum required TSP at a volume of 490 ft3 is 15,829 lbs.

Converting this value to grams and dividing by the maximum post-accident water volume of 867,830 gallons (converted into liters of water) yields a sample size of 2.19 grams TSP/liter water. This TSP sample size can be used for any TSP volume that is greater than or equal to the associated TS minimum TSP weight. However, a larger TSP sample size can be used if the TSP volume is verified to be larger than 490 ft3 to allow the test to credit extra TSP margin compensating for any degradation that may have occurred. Therefore, the larger sample size allows for interpolation. Since a TSP volume of 560 ft3 is approximately 14% greater than 490 ft3, 15,829 lbs is increased by 14% to obtain 18,045 lbs. Using the same method for calculating the sample size as before yields a sample size of 2.49 grams TSP/liter water for a volume of 560 ft3. Both of these sample sizes are above the TSP concentration curve for a pH of 7.0 at a boron concentration of 3050 ppm, confirming the TSP (and associated sample size) is conservative relative to the pH requirement.

The surveillance frequency of 24 months for both SR 3.6.8.1 and 3.6.8.2 is not changed.

UFSAR Subsection 6.3.2.2.4 is also revised to identify the revised TSP value of 26,460 lbs for the total weight of TSP contained in the pH adjustment baskets. This change does not adversely impact the ability to control the pH of the water in the containment sump and does not change the physical design of the baskets. The change to the TSP value does not affect how the TSP mixes with the containment water or conditions of extended plant operation following a postulated accident. The dissolution time of the TSP of 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> is not impacted by this activity as the chemical makeup of the TSP is not changed. Additionally, the pH requirements are not changed. The function of the PXS to control containment pH is not adversely impacted.

Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC) No. 2.2.03.08d inspects the pH adjustment baskets and confirms the total calculated volume of the baskets is 560 ft3.

The ITAAC does not identify the amount of TSP needed for buffering the containment water following a postulated accident. This ITAAC is not adversely impacted as the physical baskets used to distribute the TSP are not changed. Additionally, the physical dimensions and the location of the baskets are not changed. Safety analyses as described in UFSAR Chapters 6 and 15 are not adversely impacted as the containment pH control is assumed to be maintained at the required pH of 7.0 following a design basis accident in accordance with UFSAR Subsection 6.3.2.1.4 and as described in UFSAR Subsection 15.6.5.3.1.3.

Change Summary DRAFT ver er n a n allowa llow andpoint. The andpoin he testing sample size from he testing samp at 490 ft at 490 3 and 2.49 grams at d 2.49 g 26,460 lbs when accounting for 26,460 lbs when accounti post post-accident, this test is simplified accident, this test is simplif cident. When only considering boron cident. When only considering boron P at a volume of 490 ft P at a v 3 is 15,829 lbs.

9 lbs.

e maximum post e maxim

-accident water vo cc lume of e of yields a yields a sample size of 2.19 grams TSP/lite ize of 2 any TSP volume that TSP volume that is greater than or equ is g However, a larger TSP sa a larger TSP sample size can be an 490 ft3 to allow the test to credit extra TS ow the tes at may have occurred. Therefore, at may have occurred. There the larger SP volu SP volume of 560 ft m

3 is approximately 14%

approxim by 14% to obtain 18,045 lbs. Using the s 14% to obtain 18,045 lbs. Using s before yields a sample size of 2.49 grams e yields a sample size of 2.49 grams hese sample sizes are above the TSP conce e sizes are above the TSP conce ration of 3050 ppm, confirming the TSP (and ppm, confirming the TSP (an e to the pH requirement.

ement.

frequency of 24 months frequency of 24 for both SR 3.6.8.1 or bot bsection 6.3.2.2.4 is also revised to identify bsection 6.3.2.2.4 is also revised to id alal weight of TSP contained in the pH adju weight of TSP contained in the pH ad ely impact the y impact ability ity to control the pH of the to control the pH of the change the physical design the physical design of the baskets.

of the baskets.

ow the TSP mixes with the containment mixes with the containment w following a p following a ostulated accident. The dissol lated ac this activity as the chemical makeup this activity as the chemi requirements are not changed. The requirements are not change adversely impacted.

mpacted Inspections, Tests, Analyses, sts, A pH adjustment baskets and aske The ITAAC T

does not ide s not following a postulated following a postulate used to distribute t used to distribute ocation of the ba ocation of the ba 15 are not 15 are not requ requ

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 11 of 17 The proposed changes do not affect any function or features ability to be used for the prevention and mitigation of accidents. No system, structure, or component (SSC) function is changed. The proposed changes do not involve nor interface with any SSC accident initiator or initiating sequence of events related to the accidents evaluated in the plant-specific Design Control Document (DCD) or UFSAR. The proposed changes do not affect the radiological source terms (i.e., amounts and types of radioactive materials released, their release rates and release durations) used in the accident analyses. No system or design function or equipment qualification is negatively affected by the proposed changes. The changes do not result in a new failure mode, malfunction or sequence of events that could adversely affect a radioactive material barrier or safety-related equipment. The proposed changes do not allow for a new fission product release path, result in a new fission product barrier failure mode, or create a new sequence of events that would result in significant fuel cladding failures. The proposed changes do not revise any aspects of the plant that could have any adverse effect on safety and security, including the site emergency plan.

4.

REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 10 CFR 52, Appendix D, Section VIII.B.5.a allows an applicant or licensee who references this appendix to depart from Tier 2 information, without prior NRC approval, unless the proposed departure involves a change to or departure from Tier 1 information, Tier 2* information, or the Technical Specifications, or requires a license amendment under paragraphs B.5.b or B.5.c of the section. The proposed change to plant-specific Tier 2 information involves a change to the Technical Specifications (COL Appendix A). Therefore, NRC approval is required prior to making the change to Tier 2 information.

10 CFR 50.36, Technical specifications, establishes the need to have Technical Specifications; including limiting conditions for operation (LCOs) and surveillance requirements (SRs). The Core Makeup Tanks (CMTs) and the trisodium phosphate (TSP) provided for pH adjustment satisfy Criterion 3 of 10 CFR 50.36(c)(2)(ii). The proposed changes have been analyzed to demonstrate that each continues to provide adequate LCOs or SRs, as applicable, for safe operation of the facility. Therefore, the proposed changes comply with the requirements of 10 CFR 50.36.

10 CFR Part 50, Appendix A General Design Criterion (GDC) 4, Environmental and dynamic effects design bases, requires, in part, that structures, systems, and components important to safety be designed to accommodate the effects of and to be compatible with the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents.

These structures, systems, and components shall be appropriately protected against dynamic effects, including the effects of missiles, pipe whipping, and discharging fluids, that may result from equipment failures and from events and conditions outside the nuclear power unit. The proposed changes do not affect the conclusion that SSCs important to safety are designed to accommodate the effects of and are compatible with the environmental conditions associated normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant-accidents.

The evaluation performed for the proposed changes demonstrate that the difference in pH that may DRAFT SC)

SC) accident acciden ant ant-specific D spe affect the radiologic affect th ased, their release rates ased, their tem tem or design function or or design f changes. The hanges changes do not change nts that could adversely nts that could adversely affect a a

he proposed changes do not allow he proposed changes do not all ssion product barrier failure mode, or ssion product barrier failure mode, or in significant fuel cladding failures. The in significant fuel cladding failures. The e plant that could have any a e plant that could hav dverse effect ect ency plan.

ncy pla irements/Criteria Section Section VIII.B.5.a allows an applicant o VIII.B.5.a allows an applic ix to depart from Tier epart from Tier 2 information, without p 2 information, withou ed departure involves a change to or d ure involves a change to or d 2* information, or the Technical Specificatio

, or the Technical Specificati der paragraphs B.5.b or B.5.c of the section B.5.b or B.5.c of the section c Tier Tier 2 information 2 in involves a change to involves a endix A) endix A). Therefore, NRC approval is requir Therefore, NRC appro nformation.

nformat CFR CFR 50.36 5

, Technical specifications, hnical specifications, es Specifications; including limiting condition pecifications; including limiting condition requirements uiremen (SRs)

SRs). The Core Makeup The Core Makeup (TSP) provided for pH adjustment sa provided for pH adjustment sa proposed changes have been analy proposed change adequate LCO adequate LCOs or or SRs, as appli proposed changes comply wit proposed changes com 10 CFR Part R Par 50, Append ppend dynamic effects desig c effects desig components importa nts i compatible with le w maintenance, nance These struc e struc dynamic dynamic fluids, t fluids, t the n the n

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 12 of 17 result are considered to be covered by the existing environmental qualification of applicable components.

Therefore, the proposed changes comply with the requirements of GDC 4.

10 CFR Part 50, Appendix A GDC 14, Reactor coolant pressure boundary, requires that the reactor coolant pressure boundary shall be designed, fabricated, erected, and tests so as to have an extremely low probability of abnormal leakage, of rapidly propagating failure, and of gross rupture. The CMT balance line is designed for the movement of water resulting from routine sampling of the CMT or makeup to the CMT.

The pH adjustment baskets provide adequate TSP to ensure that containment flooding water is buffered to prevent corrosion during long term floodup conditions. Therefore, the proposed changes comply with the requirements of GDC 14.

10 CFR Part 50, Appendix A GDC 15, Reactor coolant system design, requires that the reactor coolant system and associated auxiliary, control, and protection systems shall be designed with sufficient margin to assure that the design conditions of the reactor coolant pressure boundary are not exceeded during normal operation, including anticipated operational occurrences. The CMT balance line is designed for the movement of water resulting from routine sampling of the CMT or makeup to the CMT. Therefore, the proposed changes comply with the requirement of GDC 15.

10 CFR Part 50, Appendix A GDC 26, Reactivity control system redundancy and capability, requires, in part, that two independent reactivity control systems of different design principles. The second reactivity control system shall be capable of reliably controlling the rate of reactivity changes resulting from planned, normal power changes (including xenon burnout) to assure that the acceptable fuel design limits are not exceeded. The second reactivity control system is chemical shim (boric acid). The proposed change to the CMT upper boron concentration limit does not impact the ability of this system to provide this function since the analyses typically use the lower limit. The proposed change to the CMT boron concentration surveillance frequency provides timely detection of dilution of the CMT to verify operability of the tanks.

Therefore, the proposed changes comply with the requirement of GDC 26.

10 CFR Part 50, Appendix A GDC 27, Combined reactivity control systems capability, requires that the reactivity control systems be designed to have a combined capability, in conjunction with poison addition by the emergency core cooling system, of reliably controlling reactivity changes to assure that under postulated accident conditions and with appropriate margin for stuck rods the capability to cool the core is maintained. The proposed changes do not affect the means of making and holding the core subcritical under anticipated conditions and with appropriate margin for contingencies. Shutdown margin is not affected. Therefore, the proposed changes comply with the requirement of GDC 27.

10 CFR Part 50, Appendix A GDC 29, Protection against anticipated operational occurrences, requires that the protection and reactivity control systems be designed to assure an extremely high probability of accomplishing their safety functions in the event of anticipated operational occurrences. The proposed changes to the CMTs do not change the tanks responses to events. Therefore, the proposed changes comply with the requirement of GDC 29.

DRAFT ply ply e boundary, requi e bound fabricated, erecte fabricated d, and normal leakage, of rapidly normal leakage, ance line is designed for the ance line is designe the CMT or makeup to the CMT.

the CMT or makeup to the o ensure that containment flooding o ensure that containment flood g term floodup conditions. Therefore, g term floodup conditions. Therefore ements of GDC 14.

ements Reactor coolant system design, requires tha eactor coolant system d iated auxiliary, control, and protection syste d auxiliary, control, a argin to assure that the design conditions assure that the dary are not exceeded during normal o exceeded nal occurrences. The CMT balance line is d nal occurrences. The CMT b ulting from routine sampling of the CMT or ulting from routine sampling of th posed changes comply ed changes com with the requirement e require ppendix A GDC GDC 26, Reactivity control sys Reactivity control sys es, in part, that two independent reactivity co t two independent reactivity c es. The second reactivity control syste reactivity control system s m s he rate of reactivity changes resulting f he rate of reactivity changes including xenon burnout) to assure that the including xenon burnout) to ass eeded. The second reactivity control system eeded. The second reactivity cont osed change to the CMT upper boron con osed change to the CMT upper boro bility of this system to provide this function s bility of this system to provide this function limit. The proposed change to the CMT b mit. The proposed change to the CMT b provides timely detection of dilution of vides timely detection of dilution of Therefore, the proposed changes com ore, the proposed changes com 10 10 CFR Part CFR Part 50, Appendix 50, A

capab capability, requires ility, requires that the re tha capability, in conjunction wi ability, in conjunction of reliably controlling re ably controlling re conditions and with ap ns an maintained. The pro ed. T core subcritical bcritic contingeencies.

ncie comply with ply with 10 10 CFR CFR occ occ

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 13 of 17 10 CFR Part 50, Appendix A GDC 34, Residual heat removal, requires that a system to remove residual heat be provided. The system safety function shall be to transfer fission product decay heat and other residual heat from the reactor core at a rate such that specified acceptable fuel design limits and the design conditions of the reactor coolant pressure boundary are not exceeded. The proposed changes to the CMTs do not change the tanks responses to events. Therefore, the proposed changes comply with the requirement of GDC 34.

10 CFR Part 50, Appendix A GDC 35, Emergency core cooling, requires that a system to provide abundant emergency core cooling whose safety function is to transfer heat from the reactor core following any loss of reactor coolant at a rate such that fuel and clad damage that could interfere with continued effective core cooling is prevented and clad metal-water reaction is limited to negligible amounts. The proposed changes to the CMTs do not change the tanks responses to events.

Therefore, the proposed changes comply with the requirement of GDC 35.

10 CFR Part 50, Appendix A GDC 37, Testing of emergency core cooling system, requires, in part, that the emergency core cooling system be designed to permit appropriate periodic functional testing to assure the operability of the system as a whole. The testing of the CMT boron concentration at the proposed frequency is sufficient to assure the operability of the system. Therefore, the proposed changes comply with the requirement of GDC 37.

10 CFR Part 50, Appendix A GDC 41, Containment atmosphere cleanup, requires that systems to control fission products, hydrogen, oxygen, and other substances which may be released into the reactor containment shall be provided as necessary to reduce, consistent with the functioning of other associated systems, the concentration and quality of fission products released to the environment following postulated accidents, and to control the concentration of hydrogen or oxygen and other substances in the containment atmosphere following postulated accidents to assure that containment integrity is maintained. The pH adjustment baskets and mass of TSP provided is sufficient to support the natural removal processes within containment.

Therefore, the proposed changes comply with the requirement of GDC 41.

4.2 Precedent No precedent is identified.

4.3 Significant Hazards Consideration Determination The requested amendment proposes changes to the upper limit of the Core Makeup Tank (CMT) boron concentration Technical Specification (TS) Surveillance Requirement (SR), the mass of trisodium phosphate (TSP) required by TS Limiting Condition for Operation (LCO) and associated SR, and the frequency of performance of the CMT boron concentration TS SR.

An evaluation to determine whether a significant hazards consideration is involved with the proposed amendment was completed by focusing on the three standards set forth in 10 CFR 50.92, Issuance of amendment, as discussed below:

DRAFT be be re at a ra re at a tions of the re tions of anges to the CMTs anges to oposed changes comply oposed cha core cooling, requires core cooling, requires that a oling oling whose safety function is to whose safety function is loss of reactor coolant at a rate such loss of reactor coolant at a rate such with continued effective core cooling is with continued effective core cooling is n is limited to negligible amounts n is limited to negl

. The The ot change the tanks responses to event t change the tanks re mply with the requirement of GDC 35.

with the requirement C 37, Testing of emergency core cooling g of emerg mergency core cooling syst ergency core cooling system be designe nal testing to assure the operability of the nal testing to assure the opera e CMT boron concentration CMT boron con at the propos at the p e operability of the system ability of the system. Therefore, the ore, the uirement of GDC 37.

f GDC 0, Appendix A GDC DC 41 4, Containment atmo Containment atmo s to control fission products, hydrogen, ox s to control fission products, h y be released into the reactor co y be released into the reactor containment s consistent with the functioning of other ass consistent with the functioning of quality of fission products released to th quality of fission products released cidents, and to control the concentratio cidents, and to control the concentrat substances in the containment atmospher ubstances in the containment atmospher that containment integrity is maintained.

containment integrity is maintained.

provided is sufficient to support the ed is sufficient to support the Therefore, the proposed changes c Therefore, the pro 4.2 4.2 Precedent Precede No precedent is identified ecedent is identified 4.3 Significant Hazards ant H The requested ueste Tank (CMT (CMT Requ Requireme irem Conditio Conditio of the of the

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 14 of 17 4.3.1 Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response

No.

The proposed changes revise the TS SR of the CMT boron concentration upper limit, the frequency of the TS SR of the CMT boron concentration upper limit, and the TS and SR of the mass of TSP in the pH adjustment baskets. The pH adjustment baskets are not initiators of an accident previously evaluated.

Inadvertent operation of the CMT during power operations is evaluated in Chapter 15. However, the analysis of this event utilizes the lower boron concentration limit; therefore, the increase to the upper boron concentration limit doesnt impact this analysis. The change to the frequency of the surveillance doesnt change the probability of falling below the lower boron concentration limit because slow leaks can be detected within the new surveillance frequency and fast leaks can be detected with the CMT top temperature alarm. Therefore, the consequences of an accident previously evaluated is not impacted because the parameters credited by the safety analysis remain within limits in support of meeting requirements.

Post-accident boron concentration calculations confirm that there is adequate shutdown margin and that the maximum boron concentration of the various water sources does not cause boron to come out of solution. The equipment qualification program considers the increase and finds the differences are negligible for the materials subjected to the increase in boron concentration. The non-loss-of-coolant-accident (LOCA) safety analyses typically model minimum CMT boron concentration considering minimum safeguards and maximum boron concentration for applications considering maximum safeguards. Since the time frame of interest for applications considering maximum safeguards is after a reactor trip, these analyses are not sensitive to increases in the maximum CMT boron concentration. For cases where nominal safeguards are modeled, the increase in the CMT boron concentration would be a benefit or have no impact.

The changes to the amount of TSP required is sufficient to buffer post-accident pH in the short-term and long-term to prevent stress corrosion cracking and help with iodine retention in solution within containment in accordance with analysis assumptions used in dose analysis.

Therefore, the proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated.

4.3.2 Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?

Response

No.

The proposed changes do not change the design function of the CMTs or the pH adjustment baskets. These proposed changes do not introduce any new equipment or components that would result in a new failure mode, malfunction or sequence of events that could adversely affect safety-related or non-safety-related DRAFT ed?

ed?

on concentration uppe on conce centration upper limit, and centration uppe djustment baskets. The pH djustment baskets.

accide accident previously evaluated.

nt previously eval ower operations is evaluated in ower operations is evaluated is event utilizes the lower boron is event utilizes the lower boro e to the upper boron concentration limit e to the upper boron concentration limit nge to the frequency of the surveillance nge to the frequency of the surveillance ng below the lower boron concentration lim ng below the lower boro ed within within the new surveillance frequency the new surve the CMT top temperature alarm T top temperatu

. Therefo t previously evaluated is not impacted bec valuated is he safety analysis remain within limits in he safety analysis remain n concentration calculations confirm that ncentration calculations confirm tha n and that the maximum boron concentratio the maximum boron concentratio not cause boron to come out of solution. The on to come out of solution. Th onsiders the increase and fi ease and find nds the differe differe s subjected to the increase in boron con subjected to the increase in t-accident (LOCA) safety analyses typica accident (LOCA) safety ana centration considering minimum safe centration considering minimu oncentration for applications considering m oncentration for applications conside frame of interest for applications consid frame of interest for applications cons reactor trip, these analyses are not se reactor trip, these analyses are not se boron concentration. F boron concentration. For cases wh or cases wh increase in the CMT boron concen rease in the CMT boron concen The changes to the amount o The changes to in the short in the short-term and long term a iodine retention in so iodine retention in assumptions used in sumptions used in Therefore, the p efore probability or ability 4.3.2 4.

Does th oes th kind o kind o R

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 15 of 17 equipment. This activity will not allow for a new fission product release path, result in a new fission product barrier failure mode, or create a new sequence of events that would result in significant fuel cladding failures.

Therefore, the proposed amendment does not create the possibility of a new or different kind of accident from any accident previously evaluated.

4.3.3 Does the proposed amendment involve a significant reduction in a margin of safety?

Response

No.

The change to the margin provided for initial loading of the pH adjustment baskets from 15% to 14% continues to satisfy the minimum pH requirement, even with allowance for degradation of the TSP. Post-accident boron concentration calculations confirm that there is adequate shutdown margin and that the maximum boron concentration of the various water sources does not cause boron to come out of solution as a result of the revision to the CMT boron concentration.

The non-loss-of-coolant-accident (LOCA) safety analyses typically model minimum CMT boron concentration considering minimum safeguards and maximum boron concentration for applications considering maximum safeguards.

Since the time frame of interest for applications considering maximum safeguards is after a reactor trip, these analyses are not sensitive to increases in the maximum CMT boron concentration. For cases where nominal safeguards are modeled, the increase in the CMT boron concentration would be a benefit or have no impact.

The change to the frequency of boron concentration surveillance doesnt change the validation of the CMTs to support safety analysis initial conditions. No safety analysis or design basis acceptance limit/criterion is challenged or exceeded by the requested change, thus no margin of safety is reduced.

Therefore, the proposed amendment does not involve a significant reduction in a margin of safety.

4.4 Conclusions Based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

5.

ENVIRONMENTAL CONSIDERATIONS The requested amendment proposes changes to the upper limit of the Core Makeup Tank (CMT) boron concentration Technical Specification (TS) Surveillance Requirement (SR), the mass of trisodium phosphate (TSP) required by TS Limiting Condition for Operation (LCO) and associated SR, and the frequency of performance of the CMT boron concentration TS SR.

DRAFT nce nce ossibility of a new ossibilit aluated.

aluated.

cant reduction in a margin cant reduction in a itial loading of the p itial loading of the pH adjustment baskets kets fy the minimum pH requirement, even with fy the minimum pH requirement, even with e TSP.

TSP. Post-accident boron concentrat cident is adequate shutdown margin and tha equate shutdown of the various water sources does not caus us water sou result of the revision to the CMT boron con ion to th

-accident (LOCA) safety analyses typ accident (LOCA) safety an n concentration consi concentratio dering minimum s g minim ncentration for applications considering max ration for applications considering m ame of interest for applications considering erest for applications considering or trip, these analyses are not sensitive to in analyses are not sensitive to concentration. For cases where nominal sa or cases where nominal sa in the CMT boron concentration would be in the CMT boron concentratio hange to the frequency of boron concentrat hange to the frequency of boron validation of the CMTs to support safety an validation of the CMTs to suppor nalysis or design basis acceptance limit/cr nalysis or design basis acceptance l the requested change, thus no margin of s the requested change, thus no margin o Therefore, the proposed amendment Therefore, the proposed amendment margin of safety.

argin of safety 4.4 4.4 Conclusions Conclusions Based on the considerations ased on the considera the health and safety of th ealth and safety of th manner, (2

, (2) such activ

) such activ regulations, and (3) t ns, a defense and secu and s ENVIRONMENTAL ENVIRONMENTAL he r he requested equested T) boron T) boron f tr f tr

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 16 of 17 (i)

There is no significant hazards consideration.

As documented in Section 4.3, Significant Hazards Consideration Determination, of this license amendment request, an evaluation was completed to determine whether a significant hazards consideration is involved by focusing on the three standards set forth in 10 CFR 50.92, Issuance of amendment. The Significant Hazards Consideration Determination determined that (1) the proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated; (2) the proposed amendment does not create the possibility of a new or different kind of accident form any accident previously evaluated; and (3) the proposed amendment does not involve a significant reduction in a margin of safety. Therefore, it is concluded that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and accordingly, a finding of no significant hazards consideration is justified.

(ii)

There is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite.

The requested amendment proposes changes to the upper limit of the Core Makeup Tank (CMT) boron concentration Technical Specification (TS) Surveillance Requirement (SR),

the mass of trisodium phosphate (TSP) required by TS Limiting Condition for Operation (LCO) and associated SR, and the frequency of performance of the CMT boron concentration TS SR. The proposed changes are unrelated to any aspect of plant construction or operation that would introduce any change to effluent types (e.g., effluents containing chemicals or biocides, sanitary system effluents, and other effluents) or affect any plant radiological or non-radiological effluent release quantities. Furthermore, the proposed changes do not affect any effluent release path or diminish the functionality of any design or operational features that are credited with controlling the release of effluents during plant operation. Therefore, it is concluded that the proposed amendment does not involve a significant change in the types or significant increase in the amounts of any effluents that may be released offsite.

(iii) There is no significant increase in individual or cumulative occupational radiation exposure.

The requested amendment proposes changes to the upper limit of the Core Makeup Tank (CMT) boron concentration Technical Specification (TS) Surveillance Requirement (SR),

the mass of trisodium phosphate (TSP) required by TS Limiting Condition for Operation (LCO) and associated SR, and the frequency of performance of the CMT boron concentration TS SR. The proposed changes in the requested amendment do not affect or alter any walls, floors, or other structures. Plant radiation zones and controls under 10 CFR 20 preclude a significant increase in occupational radiation exposure. Therefore, the proposed amendment does not involve a significant increase in individual or cumulative occupational radiation exposure.

Based on the above review of the proposed amendment, it has been determined that anticipated construction and operational effects of the proposed amendment do not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant mination minatio ermine whet ermine ee standards set fo ee stand Hazards Consideration Hazards C ment does not involve a ment does not of an accident previously of an accident pr ate the possibility of a new or ate the possibility of a n y evaluated; and (3) the proposed y evaluated; and (3) the propos in a margin of safety. Therefore, it is in a margin of safety. Therefore, it is es not involve a significant hazards es not involve a significant hazards in 10 in 10 CFR 50.92(c), and accordingly, a 2(c), and accordingly, a tion is justified.

on is j ypes or significant increase in the amounts ignificant increa e.

poses changes to the upper limit of the Core poses changes to the upper limit Technical Specification (TS) Surveillance Re chnical Specification (TS) Surveillan osphate (TSP) required by TS Limiting Cond e (TSP) required by TS Limiting Co SR, and the frequency of performance d the frequency of performance R. The proposed changes are unrelated osed changes are unrelated eration that would introduce any change to e introduce any change to e micals or micals or biocides, sanitary system effluents biocides, sanitary syst diological or non diological or no -radiological effluent relea gical e changes do not affect any effluent release changes do not affect any effluent sig sign or operational features that are cred n or operational features that are ents during plant operation. Therefore, it is c ents during plant operation. Therefore, it is oes not involve a significant change in the ty s not involve a significant change in the ty of any effluents that may be released offsite effluents that may be released offsite (iii)

(iii) There is no significant increase in There is no signifi exposure.

exposure The requested amendment pro equested amendment (CMT) boron concentration oron concentration T the mass of trisodium pho of trisodium pho (LCO) and associated ass concentration TS SR on TS or alter any walls ny wa 10 1

CFR 20 pre 20 pre the propose the propose cumulativ cumulativ

ND-20-XXXX Core Makeup Tank Boron Concentration Requirements (LAR-20-004)

Page 17 of 17 increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

6.

REFRENCES None.

DRAFT n se n se nmental nmenta with the prop with th

Southern Nuclear Operating Company ND-20-XXXX Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Proposed Changes to Licensing Basis Documents (LAR-20-004)

Insertions Denoted by Blue Underline and Deletions by Red Strikethrough Omitted text is identified by three asterisks ( * * * )

(This Enclosure consists of 2 pages, including this cover page)

DRAFT rating Plant (VEGP) Units 3 and 4 P) Units roposed Changes to Licensing Basis Do roposed Changes to Licensin (LAR-20 20-004 0

)

sertions Denoted by rtions Denoted by Blue Blue Underline and Underline and R

Omitted text is Omitted text is identified by identified by

ND-20-XXXX Proposed Changes to Licensing Basis Documents (LAR-20-004)

Page 2 of 2 Revise UFSAR Subsection 6.3.2.2.4, pH Adjustment Baskets, as shown below:

[* * *]

The total weight of TSP contained in the baskets is at least 25,920 26,460 pounds. [* * *]

Revise UFSAR Subsection 9.3.6.2.6, Borated Makeup, as shown below:

The makeup pumps are used to provide makeup at the proper boron concentration to the passive core cooling system accumulators, core makeup tanks, in-containment refueling water storage tank, and to the spent fuel pool. Makeup to these locations is at boric acid concentration as required, which can be varied from 0 to 4375 (nominal) parts per million (2.5 weight percent). A mixture of 2.5 weight percent boric acid and demineralized water is provided by taking suction from both the boric acid storage tank and the demineralized water tank.

Revise LCO 3.5.2, CMTs - Operating, Surveillance Requirement (SR) as shown below:

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.2.4 Verify the boron concentration in each CMT is 3400 ppm, and 3700 4500 ppm.

7 days 31 days Revise LCO 3.6.8, pH Adjustment, LCO and SR as shown below:

LCO 3.6.8 The pH adjustment baskets shall contain 25,920 26,460 lbs of trisodium phosphate (TSP).

[* * *]

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY 3.6.8.1 Verify the pH adjustment baskets contain 25,920 26,460 lbs of TSP.

24 months DRA fy the boron concentration in each CMT is fy the boron concentration in each

d RAFT pounds. [* * *]

pounds.

wn below:

wn belo r boron concentration to the passive r boron concentration to the passiv n-containment refueling water storage containment refueling water storage cations is at boric acid concentration as cations is at boric acid concentration as nal) nal) parts per million parts per million (2.5 weight percent). A (2.5 weight percent). A F

ineralized water is provided by taking suct eralized water is provid emineralized water tank.

lized water tank.

g, Surveillance Requirement

, Surveillance Requirement (S (SR)

R as sho TS SURVEILLANCE NCE AF AF RA 3700 37 4500 ppm.

pm.

RA RA RA R

evise LCO 3.6.8, pH Adjustment, LCO an evise LCO 3.6.8, pH Adjus LCO 3.6.8 LCO The pH adjustmen pH adju phosphate (TS phosphate (TS

[* * *]

[

SURVEILLANCE REQUIRE SURVEILLANCE REQU D

1 Verify Verify of of D

Southern Nuclear Operating Company ND-20-XXXX Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Conforming Changes to the Technical Specification Bases (For Information Only)

(LAR-20-004)

Insertions Denoted by Blue Underline and Deletions by Red Strikethrough Omitted text is identified by three asterisks ( * * * )

(This Enclosure consists of 4 pages, including this cover page)

DRAFT rating Plant (VEGP) Units 3 and 4 P) Units ng Changes to the Technical Specificatio the Technical Specificatio (For Information Only) ormation O (LAR-20 20-004 00 )

ertions Denoted by rtions Denoted by Blue Blu Underline and D Underline and D RA Omitted text is identified by th Omitted text is identified by th

ND-20-XXXX Conforming Changes to the Technical Specification Bases (For Information Only) (LAR-20-004)

Page 2 of 4 Revise Technical Specifications Bases B 3.5.2, CMTs - Operating, as shown below:

BASES SURVEILLANCE REQUIREMENTS SR 3.5.2.4 The minimum boron concentration of 3400 ppm assures the CMT safety analysis minimum reactivity control requirements are met. The maximum boron concentration allowed within each CMT at any time shall be 4500 ppm to prevent overboration.

Verification every 7 days 31 days that the boron concentration in each CMT is within the required limits ensures that the reactivity control from each CMT, assumed in the safety analysis, will be available as required. The 7 day 31 day Frequency is adequate to promptly identify changes which could occur from mechanisms such as in-leakage considering the provisions for monitoring temperature of the inlet line and top of the CMT. Additionally, the top of the CMT has control room indication and an alarm on increased temperature, which would be indicative of in-leakage.

DRAFTT on of 3400 ppm assures the CMT on of 3400 ppm assures the CMT FT tivity control requirements are met.

tivity control require The he FT tion allowed within each CMT at any time tion allowed within each FT event overboration.

nt overboration.

AFT days 31 days s that the boron concentration that the bo AF A

hin the required limits ensures that the react its ensu ach CMT, assumed in the safety analysis, w ach CMT, assumed in the safety required. The equired. The 7 day 31 day Frequency is a Frequen AF AF identify changes which could occur from me fy changes which could occur from m eakage considering the provisions for monit onsidering the provisions for monit AF e inlet line and top of the CMT nd top of the CMT. Additionally Additiona RAA as control room indication and an alarm on ndication and an alarm on RA which would be indicative of in which would be indicative of in-leakage.

RA RA RA

ND-20-XXXX Conforming Changes to the Technical Specification Bases (For Information Only) (LAR-20-004)

Page 3 of 4 Revise Technical Specifications Bases B 3.6.8, pH Adjustment, as shown below:

BASES LCO The requirements to maintain the pH adjustment baskets 25,920 26,460 lbs of TSP assures that for DBA releases of iodine into containment, the pH of the containment sump will be adjusted to enhance the retention of the iodine.

SURVEILLANCE REQUIREMENTS SR 3.6.8.1 The minimum amount of TSP is 25,920 26,460 lbs. This weight is based on providing sufficient TSP to buffer the post accident containment water to a minimum pH of 7.0. Additionally, the TSP weight is based on treating the maximum volume of post accident water (867,308 867,830 gallons) containing the maximum amount of boron (3014 3050 ppm) as well as other sources of acid. The minimum required mass of TSP is 25,920 26,460 lbs at an assumed assay of 100%.

While a weight is specified, the normal manner to confirm the weight limit is met is by measuring the volume of the TSP contained in the pH adjustment baskets. The minimum measured volume of TSP is 480 490 ft3, which is based on the minimum required mass of TSP (25,920 26,460 lbs) and assumes the minimum density of TSP. The minimum TSP density is based on the manufactured desnity (54 lbm/ft3), since the density may increase and the volume decrease, during plant operation, due to agglomeration from humidity inside the containment. The TSP volume of 560 ft3 at the initial loading (i.e.,

prior to compaction and agglomeration) includes margin (about 1514%) to account for degradation of TSP during plant operation.

The periodic verification is required every 24 months, since access to the TSP baskets is only feasible during outages, and normal fuel cycles are scheduled for 24 months. Operating experience has shown this Surveillance Frequency acceptable due to the margin in the volume of TSP placed in the containment building.

DRAFT baskets baskets 25,920 T

es of iodine into es of iodine mp will be adjusted to mp will be adjusted T

SP is SP is 25,920 2

26,460 460 lbs. This weight is lbs FT F

icient TSP to buffer the post accident TSP to buffer the p a minimum pH of 7.0. Additionally, the TSP m pH of 7.0. A n treating the maximum volume of post accid aximum v 867,830 86 gallons) containing the maximum a taining t A

3050 3050 ppm) as well as other sources of acid ppm) as well as other source A

equired mass of TSP is ired mass of TSP 25,920 26,460 26,460 lbs a AF AF f 100%.

hile a weight is specified, the normal manne specified, the normal manne imit is met is by measuring the volume of th mit is met is by measuring the volume of th pH adjustment baskets. The minimum me pH adjustment baskets. The 480 480 490 490 ftft3, which is based on the min

, which is based RA R

(25,9200 26,460 26,4 lbs) and assumes th nd ass RA RA minimum TSP density is based o m TSP density is bas lbm/ft3), since the density may

), since the density may during plant operation, due t ring plant operation, due t containment. The TSP vo containment. The TSP vo prior to compaction and prior 15 1514 1 %) to account f DR DR The periodic ve The perio the TSP bas TSP ba cycles are are shown t the v

ND-20-XXXX Conforming Changes to the Technical Specification Bases (For Information Only) (LAR-20-004)

Page 4 of 4 BASES SURVEILLANCE REQUIREMENTS (continued)

SR 3.6.8.2 Testing must be performed to ensure the solubility and buffering ability of the TSP after exposure to the containment environment. A representative sample of TSP from one of the baskets in containment is submerged in 1.0 +/- 0.01 liter of water at a boron concentration of 3014 3050 ppm that has been heated to a temperature of 71 +/- 5°C (160 +/- 9°F). The solution is allowed to stand at this temperature for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> without agitation. The solution is then cooled to 25 +/- 5°C (77 +/-

9°F) and the pH is measured. The solution pH should rise to 7.0. A TSP sample size of 2.14 2.19 grams is used if the TSP volume is verified to be at least 480 490 ft3 (minimum required). However, a larger TSP sample size can be used if the measured volume is verified to be greater than the minimum. For example, if the TSP volume is verified to be 560 ft3, then a representative sample of 2.41 2.49 grams can be used.

Agitation of the test solution is prohibited, since an adequate standard for the agitation intensity cannot be specified. The time of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> without agitation is necessary to allow time for the dissolved TSP to naturally diffuse through the sample solution. In the post LOCA sump area, rapid mixing would occur due to liquid flow, significantly decreasing the actual amount of time before the required pH is achieved.

DRAFTT ubility and buffering ubility and buffe ntainment environment. A tainment environme of the baskets in containment of the baskets in containm er at a boron co er at a ncentration of ation of ted to a temperature of 71 ted to a

+/- 5°C wed to stand at this temperature for 4 wed to stand at this temperature for 4 olution is then cooled to 25 olution is then coole

+/- 5°C (77 +/-

ed. The solution pH should rise to ed. The solution pH shou 7.0. A 2.199 grams is used if the TSP volume is grams is used if the AF 480 490 ftft3 (minimum required). However, a (minimum req AF A

size can be used if the measured volume sed if the m is eater than the minimum. For example, if the eater than the minimum. For fied to be 560 ft fied to be 3, then a representative sam represe can be used.

an be used.

on of the test solution is prohibited, since an test solution is prohibited, since an the agitation inntensity cannot be specified. T tensity cannot be specified.

without agitation is necessary to allow time fo s necessary to allow time fo naturally diffuse through the sample soluti naturally diffuse through the s area, rapid mixing would occur due to l area, rapid mixing would oc dec d

reasing the actual amount of time asing the actual amou achieved.

d.

DR DR DR DR DR DR