bell bend nuclear power plant - response to rai no. 84. · the enclosure provides our response to...

S I.I -•

R. R. Sgarro PPL Bell Bend, LLC * , #

Director - Regulatory Affairs Two North Ninth StreetAllentown, PA18101-1179 mm"

Tel. 610.774.7552 Fax 610.774.2618rrsqarro•Dpplweb.com "

March 30, 2012

ATTN: Document Control DeskU.S. Nuclear Regulatory CommissionWashington, DC 20555-0001

BELL BEND NUCLEAR POWER PLANTRESPONSE TO RAI NO. 84BNP-2012-088 Docket No. 52-039

References: 1) M. Canova (NRC) to R. R. Sgarro (PPL Bell Bend, LLC), Bell Bend COLA -Request for Information No. 84 (RAI No. 84) - SBPA 3990, email datedMarch 23, 2010

2) BNP-2012-072, R. R. Sgarro (PPL Bell Bend, LLC) to U.S. NRC, "ScheduleInformation for Responses to Requests for Additional Information for the BellBend FSAR," dated March 14, 2012

The purpose of this letter is to respond to the request for additional information (RAI) identifiedin reference 1. In reference 2, PPL Bell Bend, LLC (PPL) indicated that PPL would provide aresponse to Request for Additional Information (RAI) No. 84 Questions 09.02.05-3, 09.02.05-4Bullets 7 & 11, and 09.02.05-5 Bullet 2, on or before March 31, 2012. This RAI addresses theUltimate Heat Sink as discussed in Section 9.2.5 of the Final Safety Analysis Report (FSAR), assubmitted in Part 2 of the Bell Bend Nuclear Power Plant Combined License Application (COLA)

The enclosure provides our response to RAI No. 84, Questions 09.02.05-3, 09.02.05-4 Bullets 7& 11, and 09.02.05-5 Bullet 2, which includes revised COLA content. The revised COLAcontent will be included in a future revision of the BBNPP COLA. The future revision of theCOLA is the only new regulatory commitment in this letter.

Should you have questions, please contact the undersigned at 610.774.7552.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on March 30, 2012.

Respectfully,

Rocco R. Sga/

RRS/kw

Enclosure: As stated

March 30, 2012 BNP-2012-088

cc: (w/ Enclosure)

Mr. Michael CanovaProject ManagerU.S. Nuclear Regulatory Commission11555 Rockville PikeRockville, MD20852

(w/o Enclosure)

Mr. William DeanRegional AdministratorU.S. Nuclear Regulatory CommissionRegion I475 Allendale RoadKing of Prussia, PA19406-1415

March 30, 2012 BNP-2012-088 Enclosure

Enclosure

Response to RAI No. 84, Questions 09.02.05-3, 09.02.05-4 Bullets 7 & 11,and 09.02.05-5 Bullet 2


RAI No. 84

Question 09.02.05-3

Additional information is needed to identify the location for each train of the skid-mountedchemical treatment system. Furthermore, the impact of chemical treatment system failure onsafety-related equipment needs to be considered and addressed in accordance with GDC 2requirements. Also, this information needs to be reflected in the Bell Bend FSAR.

Response:

Chemical storage volumes were determined based on 14-day storage for sodium hypochloriteand minimum 30-day storage for all other chemicals. The shorter storage for sodiumhypochlorite was selected to minimize degradation of the chemical during storage. This is not aconcern for other chemicals. Using these storage criteria, the expected chemical dosages, andthe average blowdown flow results in the following design storage volumes for each EssentialService Water System (ESWS) cooling tower (as adjusted for commercially available vessels):

Sulfuric acid - 1000 gallon tankSodium hypochlorite - 2500 gallon tankHEDP deposit control agent (BL5323) - 300 gallon toteBiodispersant - 300 gallon tote

The skid-mounted chemical injection pumps and associated controls are located in the WaterTreatment Building, with the chemical storage tanks located immediately outside the WaterTreatment Building. This location was chosen to maintain the standoff distance for toxicity of823 feet from the main control room (MCR) air intakes for the deposit control chemical BL5323.The valves, piping and pipe supports used for chemical injection inside the Essential ServiceWater (ESW) Pump Buildings are designed to SSC Quality Class D and SSC Seismic Class IIrequirements. This is a departure from the certified design. The non-safety related, non-seismic water treatment piping from the Water Treatment Building terminates at a seismicallyqualified penetration at the interface with the ESW Pump Building wall. Therefore, there will notbe an uncontrolled release of water treatment chemicals into the ESW Pump Building during orfollowing a seismic event. If a chemical feed line outside the ESW Pump Building ruptures, theeffects of the break are bounded by Document 2008-12505, Rev. 3, "Analysis of OnsiteChemical Hazards." The grading and drainage in the vicinity of the UHS cooling towers andESW Pump Buildings is such that leakage is directed away from these safety-related structures.

Chemical treatment system failure would result in gradual scaling of the ESWS during normaloperation. This condition would be detected by routine monitoring, and provide adequate timefor corrective action. Chemical treatment system failure will not affect the function of the ESWSfollowing a DBA. After the start of a DBA, there would be no make-up, blowdown, or chemicaltreatment at the cooling tower. A failure of the chemical treatment system will not prevent safetyrelated equipment from performing its design function.

The chemical treatment system does not perform a safety related function, and the portions ofthe system located outside the ESW Pump Buildings are designed to meet SSC Quality GroupE, non-seismic requirements. For the storage amounts listed above for each ESWS coolingtower, a failure of the chemical treatment system or loss of containment for any of the watertreatment chemicals would not pose an onsite hazard to control room operators, or cause a lossof integrity of safety related structures.

1


Separate skid-mounted metering pumps and associated controls, also located in the WaterTreatment Building, are used for treatment of the Combined Waste Water Retention Pond. Thepurpose of this equipment is to dispense sodium bisulfite to the blowdown water to aid in theremoval of chlorine. The injection point is close to the Combined Waste Water Retention Pond,which allows combined treatment of all discharges with one injection point. The design storagevolume for sodium bisulfite (38% solution) outside the Water Treatment Building is 300 gallons.Failure of this equipment would not impact any safety related SSCs. Loss of inventory of thesodium bisulfite would not pose a threat to the health or safety of control room operators sincethis location is beyond the 479 ft. standoff distance for toxicity from the MCR air intakes.

COLA Impact:

BBNPP will insert FSAR Figure 9.2-12, and Figures 9.2-13 and 9.2-14, derived from U.S. EPRFSAR Figures 9.2.5-1 and 9.2.5-2 respectively, to reflect the change in design classification ofportions of the piping used for chemical treatment inside the ESW Pump Buildings. The changein design classification is a departure from the U.S. EPR FSAR. The inserted figures are asshown in the COLA Impact for the response to RAI No. 84, Question 09.02.05-4 Bullet 7

Table 1.7-2 is revised to list the BBNPP specific Figure 9.2-12, "ESWS Blowdown Line," Figure9.2-13,"Ultimate Heat Sink Piping and Instrumentation Diagram," and, Figure 9.2-14,"UHSSystems."

FSAR Table 3.2-1, "Classification Summary for Site-Specific SSCs" is revised to add valves30PED10/20/30/40 AA022 "ESW Chemical Treatment System Isolation Valves" and PED10/20/30/40 "ESW Chemical Treatment System Piping" that have been changed from QualityGroup E, Non-Seismic to Quality Group D, Seismic Category I1. The change from QualityGroup E, Non-Seismic, to Quality Group D, Seismic Category II, is a departure from theCertified Design.

The FSAR Section 9.2.5 will be revised as shown below, in a future COLA revision:

9.2.5.2.2 Blowdown

Blowdown from the ESWS cooling tower basins is a non safety-related function. The site-specific blowdown arrangement for each ESWS cooling tower basin is a pressurized line thatFuns from connects to the ESWS pump's discharge piping, and runs to a header in the yardarea-where-which joins all four blowdown lines-join. The header then runs to the CombinedWaste Water Retention Pond, as shown in Figure 9.2-12.

The connection at the ESWS pump discharge is made through a safety-related MOV that closesautomatically in the event of a DBA to ensure ESWS integrity. Check valves are also locateddownstream of each of these MOVs for backflow prevention, as shown in Figure 9.2-13. Thenormal blowdown isolation MOVs are in the certified design scope and are discussed herein foradditional clarity.

An altemate-emergency blowdown path is provided from the same pump discharge connectionthrough a second safety-related MOV in case the normal path is unavailable. The alternateemergency blowdown isolation MOVs are in the certified design scope and are discussed hereinfor additional clarity.

Heat tracing will be used as necessary for freeze protection of site-specific blowdown piping toensure its availability during low temperature conditions.

2


Under normal operating conditions and shutdown/cooldown conditions, the normal blowdownvalves automatically modulateare adiusted from the MCR as necessary to control blowdownflow from their ESWS trains to the Combined Waste Water Retention Pond to help ensurecooling water chemistry remains within established limits. The debris filters which are in theESWS cooling water loop (without a bypass) also connect to the blowdown line and dischargqethe backwash when predetermined differential pressure setpoints are reached. Normally onlytwo (2) ESW cooling towers are blowing down water, since normally only two ESW coolingtowers are operating. Shutdown/cooldown conditions typically utilize all four (4) ESW coolingtowers. In both cases, blowdown combines with the CWS blowdown and discharges into theCombined Waste Water Retention Pond.

In the event of a DBA condition, the ESWS Blowdown is not utilized, except for debris filterbackwash discharge which is directed to the Emergency Blowdown line, and MOVs are closedautomatically, so as not to impact safety-related systems. During this condition, the debrisfilters may still be backwashed, as the system will still allow flow duringq DBA conditions. Allnon-safety related, augmented quality blowdown piping within the ESWS Pump Buildings isdesigned to SSC Quality Group D, Seismic Class II requirements This is a departure from theU.S. EPR FSAR, and will not adversely impact safety-related systems during or following aseismic event (as described in Section 9.2.5.1).

Separate skid-mounted metering pumps and associated controls, also located in the WaterTreatment Building, are used for treatment of the Combined Waste Water Retention Pond. Thepurpose of this equipment is to dispense sodium bisulfite to the blowdown water to aid in theremoval of chlorine. The injection point is close to the Combined Waste Water Retention Pond,which allows combined treatment of all discharges with one injection point. The design storagevolume for sodium bisulfite (38% solution) outside the Water Treatment Building is 300 gallons.Failure of this equipment would not impact any safety related SSCs. Loss of inventory of thesodium bisulfite would not pose a threat to the health or safety of control room operators sincethis location is beyond the 479 ft standoff distance for toxicity from the MCR air intakes.

9.2.5.2.4 ESWS Makeup Water Chemical Treatment

Chemical additives are used in the ESWS cooling towers to reduce scaling and corrosion, andto treat potential biological contaminants, which are added via the ESWS normal makeup waterpiping. The ESW makeup chemical treatment system provides the chemistry control to theESWS cooling tower basins. Chemicals can be added to the ESWEMS Retention Pond throughthe Raw Water Supply System.

The treatment system consists of multiple skid-mounted arrangements, one for each ESWScooling tower. The skid mounted equipment is located inside the Water Treatment Building, withthe chemical storage tanks located outside the Water Treatment Building. Each skid containsthe equipment, instrumentation and controls to fulfill the system's function of both monitoringand adjusting water chemistry. The root valves at thOcnnoctfin..s f_ . a..p.•.l..s,,, lines, andsupports inside the ESW Pump Buildings that are used for chemical iniection W_ the-- SWSpith•-are safety related as necessarydesigned to SSC Quality Group D. SSC Seismic Class IIrequirements to ensure the integrity of .ESWS pipi•g prevent spillage of chemicals inside theESW Pump House during and following a QBA seismic event. This is a departure from thecertified design. Chemical treatment system failure would result in gradual scaling of the ESWSduring normal operation. This condition would be detected by routine monitoring, providingadequate time for corrective action. Chemical treatment system failure will not affect thefunction of the ESWS following a DBA. After the start of a DBA, there would be no make-up,blowdown, or chemical treatment at the cooling tower. A failure of the chemical treatmentsystem will not prevent safety related equipment from performing its design function.

3


The chemical treatment system does not perform a safety related function, and the portions ofthe system that are located outside the ESW Pump Buildings are designed to meet SSC QualityGroup E. non-seismic requirements. For the storage amounts listed above for each ESWScooling tower, a failure of the chemical treatment system or loss of containment for any thewater treatment chemicals would not pose an onsite hazard to control room operators, or causea loss of integrity of safety related structures.

The specific chemicals and addition rates are determined by periodic water chemistry analyses.The cooling system water will be chemically treated to adjust pH and to control deposits,corrosion, and biological growth. Specific chemicals and concentrations are discussed in detailin BBNPP ER Section 3.3 and 3.6.

Heat tracing will be used as necessary for freeze protection of the Chemical Treatment Systemto ensure its availability during low temperature conditions.

Additions to the ESWS cooling towers are made as necessary on a periodic or continuing basis.The Susquehanna River is the source of water supplied by the RWSS. This water ischaracterized as moderately hard, alkaline water with a low dissolved solids contentaveraging143 mg/l.

An oxidizing biocide is selected to control microbiological growth in service water piping tocontrol fouling, microbiological deposits, and microbiological related corrosion in service waterpiping. Sodium hypochlorite solution is injected intermittently in the RWSS makeup line to theESWEMS Retention Pond to minimize fouling in the makeup line. Facilities for sodiumhypochlorite storage and injection also will be located near the river intake structure andchemicals will be injected near the RWSS pumps.

All components of the RWSS chemical treatment system are constructed of materialscompatible with the chemicals utilized in the treatment system.

(TBD) - Site-specific chemistry comparison for normal and emergency makeup water.

9.2.5.3.2 Piping, Valves, and Fittings

Component Description

Chemical Treatment System Components

The components of the chemical treatment system outside the ESW Pump Buildings are non-safety-related, non-seismic; the components of the chemical treatment system inside the ESWPump Buildings are non-safety-related, augmented quality, SSC Quality Group D, SeismicClass II. The components include metering pumps, pipes, chemical storage tanks, controlvalves, and sampling valves and lines.

All of these components are constructed of materials compatible with the chemicals utilized inthe treatment system.

4


9.2.5.5 Safety Evaluation

Normal ESWS makeup is a non-safety-related function, and thus requires no safety evaluationwith respect to design basis events. Similarly, both cooling tower blowdown and chemicaltreatment are non safety-related functions and require no safety evaluation. However, theconnections to safety-related piping through which the blowdown function is made and theaccompanying isolation valves are safety-related, which ensures the integrity of the safety-related piping in the event of a DBA. The safety-related blowdown isolation valves are in thecertified design scope and are discussed herein for additional clarity. The balance of theblowdown piping is also designed not to impact safety-related systems (as described in Section9.2.5.1).

5


FSAR Table 1.7-2 will be changed, in a future COLA revision, due to the response to thisquestion and RAI 84 Question 09.02.05-5 Bullet 2, as shown, below:

Table 1.7-2 - {Piping and Instrumentation Diagrams)

FSAR Figure Number Title

9.2-1 Potable Water

9.2-2 Sanitary Waste Water System

9.2-3 ESWEMS Schematic

9.2-11 Raw Water System

9.2-12 ESWS Blowdown Line

9.2-13 Ultimate Heat Sink Piping and Instrumentation Diagram

9.2-14 Ultimate Heat Sink Systems

9.2-15 Essential Service Water System Piping & Instrumentation Diagram

9.4-1 ESWEMS Pumphouse HVAC

9.4-2 ESWEMS Pumphouse HVAC Duct and Instrumentation Diagram

10.4-1 Circulating Water System P&ID (at Cooling Tower)

10.4-5 Circulating Water System P&ID (Makeup System)

10.4-8 Circulating Water System P&ID (Blowdown System)

6

March XX, 2012 BNP-2012-088 EnclosureMarch XX, 2012 BNP-201 2-088 Enclosure

FSAR Table 3.2-1 will be changed in a future COLA revision as shown, below:

Table 3.2-1 {Classification Summary for Site-Specific SSCs}

00 IOCFR50 `6

oK ytmo .0 _) .60

KKS System or SSC Appendix B z Comments/CommercialComponent -Code Description . Program Code

) ".(Note 4)

• z o0 z-0

PED Essential Service Water Recirculation Cooling System

ESW Chemical30PED1 0/20/30/40 Treatment NS-AQ D Yes UQB ANS/ASME B31.1AA022 System Isolation YB

Valves

ESW ChemicalPED 10/20/30/40 Treatment NS-AQ Q 11 Yes UQB ANSI/ASME B31.1

System Piping

7


BBNPP COLA Part 07 "Departures and Exemption Requests" will be revised as shown,below, in a future COLA revision:

1.1.15 Essential Service Water System - Blowdown and Chemical Treatment

1.1.15.1 Affected U.S. EPR Sections: Tier2, Table 3.2.2-1 and Sections9.2.1 and 9.2.5

1.1.15.2 Summary of Departure:

BBNPP has taken a departure from the SSC Quality Group and SeismicCategory applicable to portions of the piping and valves associated with thechemical treatment, normal makeup, and normal blowdown systems locatedinside the Essential Service Water (ESW) Pump Buildings, as described inFSAR Section 9.2.5, to change the existing non-seismic piping andcomponents to Seismic Category I1.

1.1.15.3 Scope/Extent of Departure:

This departure is identified in BBNPP FSAR Table 3.2-1, FSAR Section9.2.1.2 and FSAR Section 9.2.5.

1.1.15.4 Departure Justification:

BBNPP upgraded to Seismic Category II design requirements on the non-safety related piping and components to ensure that safety relatedcomponents inside the ESW Pump Building will not be adversely impacted bythe failure of adjacent non-safety related equipment after a Design BasisAccident. These non safety-related SSCs are classified as Seismic CategoryII. U.S. EPR SSCs classified as Seismic Category II are designed towithstand SSE seismic loads without incurring a structural failure that permitsdeleterious interaction with any Seismic Category I SSC. To preclude thepossibility of any adverse effects on safety-related equipment inside the ESWPump Buildings resulting from failure of non-seismic piping, the piping that ispresently identified as non-seismic will be upgraded to Seismic Category II.Since the information regarding equipment layout and pipe routing inside theESW Pump Buildings that would be required to independently justify the non-seismic classification (including potential flooding concerns in the ESW PumpBuildings) shown in the U.S.EPR FSAR is not currently available, a Departurefrom the Certified Design is made to ensure that no adverse seismicinteractions occur.

1.1.15.5 Departure Evaluation:

This Departure, associated with ESW seismic design, does not deleteriouslyaffect the safety function of the safety-related SSCs associated with the ESWsystem. Therefore, this Departure does not:

1. Result in more than a minimal increase in the frequency of occurrenceof an accident previously evaluated in the plant-specific FSAR:

8


2. Result in more than a minimal increase in the likelihood of occurrenceof malfunction of a structure, system, or component (SSC) importantto safety and previously evaluated in the plant-specific FSAR;

3. Result in more than a minimal increase in the consequences of anaccident previously evaluated in the plant-specific FSAR:

4. Result in more than a minimal increase in the consequences of amalfunction of an SSC important to safety previously evaluated in theplant-specific FSAR;

5. Create a possibility for an accident of a different type than anyevaluated previously in the plant-specific FSAR;

6. Create a possibility for a malfunction of an SSC important to safety witha different result than any evaluated previously in the plant-specificFSARm

7. Result in a design basis limit for a fission product barrier as describedin the plant-specific FSAR being exceeded or altered; or

8. Result in a departure from a method of evaluation described in theplant-specific FSAR used in establishing the design bases or in thesafety analyses.

This Departure does not affect resolution of a severe accident issue identifiedin the plant-specific FSAR.

Therefore, this Departure has no safety significance.

9


RAI No. 84

Response

Question 09.02.05-4 Bullet 7

The UHS must be capable of dissipating residual heat during normal operation andaccident conditions over the life of the plant in accordance with GDC 44 requirements.The descriptive information (including figures) related to the site-specific parts of theUHS support systems was reviewed by the staff to assess the adequacy of thesesystems to perform their UHS support functions. In addition to the information referredto in RAIs 9.2.5-02 (ID 3990/15468) and 9.2.5-03 (ID 3990/15469), the staff found thatsome of the information is incomplete, inaccurate, or inconsistent. Consequently, theapplicant needs to address the following items in this regard and revise the Bell BendFSAR as appropriate:

The design basis and site-specific parts of the blowdown system are notadequately described, figures showing important design details are not provided,and the consequences of failures on safety-related equipment are not addressed.

Response:

To maintain balanced water chemistry, the Essential Service Water System (ESWS)normal blowdown takes water off of the ESW pump discharge line in the ESWSPumphouse, interconnects to a header with the other ESW Cooling Tower blowdownlines, combines with the Circulating Water System (CWS) blowdown, and dischargesinto the Combined Waste Water Retention Pond. The system is capable of operatingunder normal and shutdown/cooldown conditions, and of supporting the debris filterbackwash even when the blowdown system is otherwise closed during accidentconditions and within the margins of the Essential Service Water Emergency MakeupSystem (ESWEMS) reserves (as given in BBNPP FSAR Section 9.2.5.3).The blowdownline is designed to have no negative impact on safety-related systems. Emergencyblowdown lines for each ESW train allow backwashing of ESW pump strainers duringemergency conditions, and are designed to SSC Quality Group C and SSC SeismicClass I requirements. The emergency blowdown line for each train terminates outside itsrespective ESW Pump Building and discharges to the ground. The normal blowdownand normal strainer debris discharge lines inside each ESW Pump Building are non-safety related, augmented quality, and are built to SSC Quality Group D and SSCSeismic Class II requirements. This is a departure from the Certified Design. Therefore,there will be no adverse impact on safety related equipment during or following a seismicevent. The normal blowdown lines outside the ESW Pump Building are non-safetyrelated and non-seismic. The ESWS blowdown descriptions in 9.2.5.2.2 and 9.2.5.5have been modified to describe this system in further detail, Table 1.7-2 has beenmodified, and Figures 9.2-12 and 9.2-15 have been added to support this systemdescription.

10


COLA Impact

FSAR Sections 9.2.1.2 will be changed, as shown below, in a future COLA revision.FSAR Sections 9.2.5.2.2 and 9.2.5.5, Tables 1.7-2 and 3.2-1, will be revised, as shownin the COLA Impact section of the response to Question 09.02.05-3, in a future COLArevision.

Figures 9.2-12, 9.2-13, 9.2-14, and 9.2-15 will be inserted into FSAR Section 9.2, asshown below, in a future revision of the COLA:

9.2.1.2 System Description

The U.S. EPR FSAR includes the following statement in Section 9.2.1.2:

The system is shown in Figure 9.2.1-1 - Essential Service Water Piping &Instrumentation Diagram.

BBNPP FSAR Section 9.2.1.2 will be revised to include the statement:

No departuroc Or .upploMe.tc.g he system is shown in Fiqure 9.2-15 -EssentialService Water Piping & Instrumentation Diaqram.}

11


Figure 9.2-12 will be inserted into FSAR Section 9.2

Fiqure 9.2-12 {ESWS Blowdown Linel

leg

F- EP

12



Figqure 9.2-13 {Ultimate Heat Sink Pipingq and Instrumentation Diagrami

•i '

ItIt

.._ . .

II , 4 1- - - - - _ _

13



Figqure 9.2-14 {Ultimate Heat Sink SystemsI

z IrCo U

C3

0.

Uj

LI

Id

14



Figqure 9.2-15 {Essential Service Water System Pipingq & Instrumentation Diagram}

SII', Ii~11

II jill,.,,: i' , Iii

L ....... I

fill

I

jr - f"

15


RAI No. 84

Question 09.02.05-4 bullet 11:

The maximum normal makeup and blowdown rates are based on maintaining threecycles of concentration in the cooling tower basin. The number of cycles ofconcentration that are appropriate is dependent on the effects of the equilibrium basinwater conditions on cooling tower performance (i.e., scale buildup and fouling) and thebasis for allowing three cycles of concentration needs to be explained and justified.

Response:

Cycles of concentration were determined based on evaluation of chemistry for makeupwater supplied to the Essential Service Water System (ESWS), conformance tochemistry controls for Ultimate Heat Sink (UHS) cooling towers as specified in the U.S.EPR design certification, and operating experience at the nearby Susquehanna SteamElectric Station which uses the Susquehanna River for makeup water supply.

Three cycles of concentration was conservatively selected to control scaling, corrosion,and biofouling. Three cycles of concentration also conservatively maximizes blowdownflow and makeup flow requirements.

The Susquehanna River is the source of makeup water supplied to the ESWS. Thiswater is characterized as moderately-hard, alkaline water with low dissolved solidscontent.

Susquehanna River chemistry data is shown in the 2006 Ecology III Annual WaterQuality and Fishes Report and in 2007 Susquehanna Steam Electric Station (SSES)quarterly tabulations. These references provide sets of data collected at two locations inthe river: the SSES sampling site, located approximately 700 feet upstream of the SSESintake; and, the Bell Bend sampling site located approximately 3800 feet downstream ofthe SSES intake. Data from the two sites are similar with the exception of totalsuspended solids (TSS). TSS data for the SSES location exhibited greater variation withlarger excursions. Susquehanna River chemistry is also discussed in BBNPP CombinedLicense Application Part 3, Environmental Report section 2.3.3.1.1, and data is tabulatedin ER Tables 2.3-40, 2.3-44, and 2.3-45. Data from the SSES location wasconservatively used for the water quality evaluation.

16


The typical Susquehanna River composition is shown in the following Table1:

Susquehanna RiverConstituent Max Mean

pH 8.2 7.8Total dissolved solids (mg/I) 196 142Total suspended solids (mg/I) 152 30Calcium Hardness (mg/I as CaCO3) 96 66Total Hardness (mg/I as CaCO3) 131 91M.O. Alkalinity (mg/I as CaCO3) 94 60Calcium (mg/I as Ca) 38.5 26.3Magnesium (mg/I as Mg) 10.0 6.2Sodium (mg/I as Na) 22.7 12.0Chloride (mg/I as Cl) 38.2 25.4Sulfate (mg/I as S04) 48.8 26.2Ortho-Phosphate (mg/I as P04) 0.7 0.2Silica (mg/I as Si02) 4.7 2.8Soluble Iron (mg/I as Fe) 0.3 0.1

The Raw Water Supply System (RWSS) includes media filters to treat SusquehannaRiver used by the ESWS as makeup. As described in the RWSS Conceptual DesignReport, the media filters will typically remove 90% of the suspended solids. The treatedmakeup would normally be less than 5 mg/I TSS and was conservatively bounded at 30mg/I TSS maximum using 80% removal at the maximum River TSS level.

The Langelier Index indicates a potential for calcite scaling above two cycles ofconcentration. Evaluation of cooling water chemistry at three cycles of concentrationshowed calcite scale to be controllable with acid treatment of the cooling water.Additional treatment with a deposit control agent containing an organic phosphonatescale inhibitor such as Hydroxyethylidene diphosphonic acid (HEDP) was alsoconservatively selected for additional scale control.

Review of this chemistry data indicates ESWS circulating water composition at threecycles of concentration is well within the US EPR design certification water chemistrylimits using scale inhibitors. Comparison of site specific chemistry to Table 9.2.5-5confirms the following:

1. Sulfuric acid addition will enable control of pH as required.

2. Total Alkalinity (after acid addition) is projected to be approximately 200 mg/I asCaCO3 which conforms to the 250 mg/I as CaCO 3 limit.

3. Calcium Hardness is projected to be less than 300 mg/I as CaCO3 which conforms tothe 900 mg/I as CaCO 3 limit.

4. Silica is projected to be less than 15 mg/I as Si0 2 which conforms to the 150 mg/I asSi0 2 limit.

5. Magnesium Hardness (MgH) is projected to be less than 125 mg/I as CaCO3 andSilica is projected to be less than 15 mg/I as Si0 2, so the MgH:Si0 2 product isprojected to be less than 1800 which conforms to the 75,000 limit.

1 S&L Report No. SL-01 0554, Rev. 0, "ESWS Water Chemistry Design Report," March 2011.

17


6. Suspended Solids (TSS) based on makeup composition is projected to be less than15 mg/I and will be bounded by 90 mg/I which conforms to the 150 mg/I limit. Thereis ample margin to accommodate particulate scrubbing from air in the cooling towers.

7. Dissolved Solids (TDS) is projected to be less than 500 mg/I which conforms to the5000 mg/I limit.

8. Ortho-Phosphate is projected to be less than 3 mg/I as P0 4 and will conform tochemical supplier recommendations. Also, the expected concentration isconservatively less than the 5 mg/I as P0 4 limit for systems without scale inhibitors.

9. Scale inhibitor will be controlled as required by chemical supplier recommendations.10. Biofouling will be controlled using sodium hypochlorite as an oxidizing biocide plus

addition of a biodispersant to enhance sodium hypochlorite effectiveness.

Consequently the U.S. EPR design certification will be bounding for the site; andcorrosion, scaling, and biofouling will be controlled effectively during normal operationand plant shutdown. With TDS concentrations projected at less than 500 mg/I, or aboutone-tenth the generic limit, there will not be any reduction in cooling tower heat rejectioneffectiveness during normal operation and plant shutdown.

Operating experience at the nearby Susquehanna Steam Electric Station also supportsthree cycles of concentration as conservative. SSES controls cooling tower waterchemistry at three to five cycles of concentration. Quarterly SSES makeup andblowdown data for 2006 and 2007 confirms actual cooling water chemistry, withconcentration factors ranging from 2.9 to 4.2 in accordance with the design three to fivecycles of concentration range. The minimum concentration factors of 2.9 and 3.3 wereobserved in August 2006 and 2007, respectively, when calcium and other dissolvedconstituents peaked each year. River flow data for the Susquehanna River indicatesAugust is also the time of minimum river flow.

Successful operation of the SSES cooling tower at three to five cycles of concentrationindicates three cycles of concentration is conservative for the Bell Bend Nuclear PowerPlant.

COLA Impact:

The COLA will not be changed as a result of this response

18


RAI No. 84

Question 09.02.05-5 Bullet 2

With respect to chemical treatment, additional information is needed to describe morespecifically the water quality specifications that are necessary to ensure adequateperformance of the ESWS (including adequate cooling tower performance). Themaintaining of specifications during normal operating, shutdown, and post-accidentconditions also needs to be described, recognizing that blowdown and chemicaltreatment are not assured functions.

Response:

At three cycles of concentration, chemical treatment is required at the Essential ServiceWater System (ESWS) cooling towers to control scaling, corrosion, sedimentation, andbiofouling during normal and shutdown operations. Specific water treatment chemicalsused are: sulfuric acid; a deposit control agent; sodium hypochlorite; and, abiodispersant.

Sulfuric acid will be used to adjust the pH to reduce the potential for calcium carbonatescale. Acid feed will be continuous to maintain a target pH in the alkaline region. Adeposit control agent with an organic phosphonate such as Hydroxyethylidenediphosphonic acid (HEDP) will be used for control of calcium carbonate scale. Thedeposit control agent formulation will also include other additives such as acrylatecopolymer(s) to protect against the possibility of calcium phosphate scale from reversionof HEDP and to control silt and iron deposition. HEDP will inhibit mild steel corrosion inthe alkaline system, so a separate corrosion inhibitor is not required. Sodiumhypochlorite solution will be used intermittently as an oxidizing biocide to controlbiofouling. A biodispersant will also be used to enhance the effectiveness of sodiumhypochlorite.

Sulfuric acid and sodium hypochlorite are commodity chemicals, while deposit controlagents and biodispersants are specialty chemicals available in proprietary formulationsfrom water treatment chemical vendors. The specific chemical treatment packages anddosages will be selected at startup based on chemistry requirements and economicsand can be adjusted when required based on routine performance monitoring.

Chemical treatment is intended to be applied consistently and water chemistry will bemonitored regularly to maintain target dosages during normal operation and shutdown.However, occasional chemical feed interruptions can be tolerated. Blowdown rates canbe temporarily adjusted to compensate for excursions if necessary.

For post-accident conditions, chemical treatment capability as shown in FSAR Figure9.2-14 will be developed to maintain the water supplied by the Essential Service WaterEmergency Makeup System (ESWEMS) within prescribed water quality limits. Thischemical injection equipment is used to inject chemicals at the ESWEMS pumphouse,and is separate and independent from the chemical treatment equipment used fornormal ESW makeup.

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COLA Impact:

BBNPP will add FSAR Figure 9.2-14, developed from AREVA DCD Figure 9.2.5-2,"Ultimate Heat Sink Systems" to the BBNPP FSAR, as shown in the COLA Impactsection of the response to Question 09.02.05-4 Bullet 7, in a future COLA revision.

BBNPP FSAR Table 1.7-2 will be revised to show addition of FSAR Figure 9.2-14asshown in the COLA Impact section of the response to Question 09.02.05-3, in a futureCOLA revision.

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