ML21334A169

Proposed License Amendment Request Removal of Refueling Water Chemical Additional Tank and Replacement of Containment Buffer Supplemental Information

ML21334A169
Person / Time
Site:	Surry
Issue date:	11/29/2021
From:	Mark D. Sartain Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
21-138A
Download: ML21334A169 (66)

Text

VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 November 29, 2021 10 CFR 50.90 U. S. Nuclear Regulatory Commission Serial No.: 21-138A Attention: Document Control Desk NRA/GDM: R2 Washington, DC 20555-0001 Docket Nos.: 50-280 50-281 License Nos.: DPR-32 DPR-37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 PROPOSED LICENSE AMENDMENT REQUEST REMOVAL OF REFUELING WATER CHEMICAL ADDITION TANK AND REPLACEMENT OF CONTAINMENT SUMP BUFFER SUPPLEMENTAL INFORMATION By letter dated September 30, 2021 (Serial No.21-138), Virginia Electric and Power Company (Dominion Energy Virginia) submitted a license amendment request (LAR) for Surry Power Station (Surry) Units 1 and 2. The proposed LAR would revise the Surry Units 1 and 2 Technical Specifications (TS) to eliminate the Refueling Water Chemical Addition Tank (CAT) and allow the use of sodium tetraborate decahydrate (NaTB) to replace sodium hydroxide (NaOH) as a chemical additive (buffer) for containment sump pH control following a loss-of-coolant accident (LOCA). By letter dated November 10, 2021, the U. S. Nuclear Regulatory Commission (NRC) informed Dominion Energy Virginia that additional information was required before the NRC would accept the LAR for review. The NRC provided Dominion Energy Virginia an opportunity to supplement the proposed LAR by submitting the requested supplemental information within thirteen working days, i.e., by November 30, 2021.

Dominion Energy Virginia's response to the NRC request for supplemental information is provided in the enclosure. The supplemental information does not affect the conclusions of the significant hazards consideration determination or the environmental assessment included in the September 30, 2021 LAR.

As a noted in the LAR, Dominion Energy Virginia respectfully requests approval of the proposed TS change by September 30, 2022, with implementation of the proposed TS change to coincide with the completion of the fall 2022 refueling outage for Surry Unit 1 and the spring 2023 refueling outage for Surry Unit 2.

Serial No. 21-138A Docket Nos. 50-280/281 Page 2 of 3 Should you have any questions or require additional information, please contact Mr. Gary D. Miller at (804) 273-2771.

Respectfully, Mark D. Sartain Vice President - Nuclear Engineering and Fleet Support Commitments contained in this letter: None

Enclosure:

Response to NRC Request for Supplemental Information Attachments:

1. Proposed Surry Unit 1 UFSAR Update (Interim)

2. Proposed Surry Units 1 and 2 UFSAR Update (Final)

COMMONWEALTH OF VIRGINIA )

COUNTY OF HENRICO )

The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Mr. Mark D. Sartain, who is Vice President - Nuclear Engineering and Fleet Support, of Virginia Electric and Power Company. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that company, and that the statements in the document are true to the best of his knowledge and belief.

Acknowledged before me this ,l L '14 day of l\1We.Mbe-r- , 2021.

My Commission Expires: °:Jv' I> 20Z3 .

GARY DON MILLER Notary R b

• Notary Public Commonwealth of Virginia /

Reg. # 7629412 My Commission Expires August 31, 20

Serial No. 21-138A Docket Nos. 50-280/281 Page 3 of 3 cc: U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Avenue, NE Suite 1200 Atlanta, GA 30303-1257 Mr. L. John Klos NRC Project Manager - Surry U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop 09 E-3 11555 Rockville Pike Rockville, MD 20852-2738 Mr. G. Edward Miller NRC Senior Project Manager - North Anna U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop 09 E-3 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Surry Power Station State Health Commissioner Virginia Department of Health James Madison Building - 7th floor 109 Governor Street Suite 730 Richmond, VA 23219

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure RESPONSE TO NRC REQUEST FOR SUPPLEMENTAL INFORMATION PROPOSED LICENSE AMENDMENT REQUEST REMOVAL OF REFUELING WATER CHEMICAL ADDITION TANK AND REPLACEMENT OF CONTAINMENT SUMP BUFFER Virginia Electric and Power Company (Dominion Energy Virginia)

Surry Power Station Units 1 and 2

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure RESPONSE TO NRC REQUEST FOR SUPPLEMENTAL INFORMATION License Amendment Request - Removal of Refueling Water Chemical Addition Tank and Replacement of Containment Sump Buffer Surry Power Station Units 1 and 2 BACKGROUND By letter dated September 30, 2021 (Serial No.21-138), Virginia Electric and Power Company (Dominion Energy Virginia) submitted a license amendment request (LAR) for Surry Power Station (Surry) Units 1 and 2. The proposed LAR would revise the Surry Units 1 and 2 Technical Specifications (TS) to eliminate the Refueling Water Chemical Addition Tank (CAT) and allow the use of sodium tetraborate decahydrate (NaTB) to replace sodium hydroxide (NaOH) as a chemical additive (buffer) for containment sump pH control following a loss-of-coolant accident (LOCA). By letter dated November 10, 2021, the Nuclear Regulatory Commission (NRG) informed Dominion Energy Virginia that additional information was required before the NRG would accept the LAR for review and provided an opportunity to supplement the proposed LAR by providing additional information to address the items detailed in their letter.

Dominion Energy Virginia's response to the NRG request for supplemental information is provided below.

NRC Request No. 1 A description of how the Na TB (sodium tetraborate decahydrate) will be stored, such as the number of baskets, size, detailed x-y-z location, and how they are designed to contain the Na TB while allowing access for the water to dissolve it.

Dominion Energy Virginia Response Seven (7) baskets will be installed in each of the Surry Unit 1 and Unit 2 Containments and will contain the required amount of NaTB chemical. Each basket will have nominal dimensions of 6' x 5' x 1.5'. The baskets will be installed on the (-)27'-7" elevation of the Surry Unit 1 and Unit 2 Containments near the annulus, as well as near the lncore Instrumentation Room. The baskets use a fine mesh supported by a perforated plate to contain the NaTB chemical that allows the containment sump water to passively dissolve the NaTB. The perforated plate and fine mesh system encompass the four basket side walls and the basket bottom. The planned installation locations of the baskets in the Surry Units 1 and 2 Containments are shown in Figures 1 and 2, respectively, and are provided for information. It should be noted that the locations could be adjusted during the design change implementation process due to unforeseen installation issues.

Page 1 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure

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Serial No. 21-138A Docket Nos. 50-280/281 Enclosure NRC Request No. 2 A summary of the post-Loss of Coolant Accident (LOCA) borated water sources, with a description of the boron concentrations considered.

Dominion Energy Virginia Response The borated water sources considered as part of the buffer replacement project are provided in Table 1.

TABLE 1 - BORATED WATER SOURCES

1. Parameter Units Minimum Maximum Refueling Water Storage Tank (RWST) 1.a Volume gal 361,916 388,917 1.b Boron Concentration ppm 2,277 2,525 Reactor Coolant System (RCS) 2.a Volume gal 63,018 67,380 2.b Boron Concentration ppm 0 2,525 Safety Injection Accumulators and Associated Piping (S/As) 3.a Volume - SIAs gal 21,682 23,201 3.b Volume - SIA Piping gal 1,104 1,104 3.c Boron Concentration ppm 2,228 2,525 SJ Piping (sum of a/13 loops) 4.a Volume gal 369 369 4.b Boron Concentration ppm 0 2,525 Page 4 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure NRC Request No. 3 A summary of the sources of other acids and bases included in the post-LOCA pH calculation, and at least a reference to how they were calculated.

Dominion Energy Virginia Response Other (non-boric acid) acids and bases considered in the post-LOCA pH calculation are summarized in Tables 2 and 3, respectively.

TABLE 2- NON-BORIC ACIDS INCLUDED IN POST-LOCA PH CALCULATION

1. Acid Source Reference(s}

1 Nitric Acid Irradiation of water §2.2.4 of NUREG/CR-5950 Irradiation of chloride bearing 2 Hydrochloric Acid §2.2.5.2 of NUREG/CR-5950 cables

• ORIGAMI in SCALE 6.2.3 3 Hydriodic Acid Released core inventory * §3.2 of Reg Guide 1.183

• §2.2.2 of NUREG/CR-5950 TABLE 3- BASES INCLUDED IN POST-LOCA PH CALCULATION

1. Base Source Reference( s}

• ORIGAMI in SCALE 6.2.3 Cesium 1 Released core inventory * §3.2 of Reg Guide 1.183 Hydroxide

• §2.3.1 of NUREG/CR-5950 Lithium 2 RCS water Plant chemistry procedure Hydroxide Page 5 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure NRC Request No. 4 A description of the methodology and results for calculating pH and the required Na TB quantity, or the analysis.

Dominion Energy Virginia Response The pH / buffer quantity analysis considers all species in the containment sump solution to be in equilibrium, i.e., it is based on steady state conditions. The sump pH is computed using guidance from NUREG/CR-5950.

The concentration of negatively charged species (anions) must equal the concentration of positively charged species (cations) for electroneutrality in the sump. The sum of negative charges for the charge balance is determined from the molal concentrations of anions B(OH)4*, B2(OH)1*, 83(QH)10*, 84(QH)1i* or 85(QH)1a3*, OH*, NQ3*, Cl*, and 1-.

The sum of positive charges for the charge balance is determined from the concentrations of H+, Na+, Cs+, and u+. The ionic activity product constant of water is modeled using the Marshall-Frank correlation 1.

Boric acid speciation is based on the temperature dependent molal-equilibrium quotients reported by Palmer2. The concentration of boron in solution based on the total mass of boric acid and NaTB must be equal to the concentration based on the contribution of all boric acid species.

Equilibrium sump conditions are determined using an analytical model which was benchmarked to site-specific buffer testing using the same buffer as will be installed.

Different inputs are utilized based on whether the calculation is determining: 1) solution pH based on buffer quantity, or 2) buffer quantity based on desired solution pH. The model iterates boric acid speciation, and either NaTB mass or pH until convergence is achieved for the boron mass balance and charge balance equations.

The amount of NaTB required for long-term post-LOCA containment sump pH control (i.e., to ensure the sump pH remains at or above 7) is approximately 10,760 lbm. This quantity is determined using the methodology described above, as well as the inputs described in the response to NRC Request No. 5.

1 Marshall, W. L., and E. U. Franck, "Ion Product of Water Substance, 0-1000°C, 1-10,000 Bars New International Formulation and Its Background," Journal of Physical and Chemical Reference Data, Vol.

10, No. 2, pp. 295-304, 1981.

2 Palmer, D. A., Benezeth, P., and D. J. Wesolowski, "Boric Acid Hydrolysis: A New Look at the Available Data," PowerPlant Chemistry, v. 2(5), pp. 261-264, 2000.

Page 6 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure NRC Request No. 5 For each case considered, a description of how input values and ranges were selected for the water and chemicals used in the calculations (e.g., water, boron, NaTB, and other acids and bases).

Dominion Energy Virginia Response

• Determination of NaTB Required The following inputs were used to determine the NaTB required to ensure the minimum required sump pH at the time when Recirculation Spray is credited for iodine removal and at 30 days for 1-train of Engineered Safety Features (ESF) and full ESF. These inputs conservatively bias high the quantities of acids and bias low the quantities of bases.

- Sump pH= 7.0

- Maximum mass of boron/boric acid in the containment sump at time of interest for the ESF scenario being investigated

- Minimum lithium concentration in RCS

- Hydrochloric acid generation due to cable irradiation at time of interest (biased high)

- Nitric acid generation due to water irradiation at time of interest (biased high)

- Maximum core iodine release at time of interest

- Minimum core cesium release at time of interest

- Minimum NaTB chemical equivalence

• Determination of Maximum Sump pH Values The following inputs were used to determine the maximum sump pH at select times for 1-train ESF and full ESF cases. These inputs conservatively bias high the quantities of bases and bias low the quantities of acids.

- Maximum NaTB mass at time of interest

- Minimum mass of boron/boric acid in the containment sump at time of interest for the scenario being investigated

- Maximum lithium concentration in RCS

- No hydrochloric acid generation due to cable irradiation

- No nitric acid generation due to water irradiation

- No core iodine release

- Maximum core cesium release at time of interest

- Maximum NaTB chemical equivalence Page 7 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure NRC Request No. 6 An explanation for how the mass of Na TB would be measured in order to meet the proposed requirement in Technical Specification 3.4.A.4.

Dominion Energy Virginia Response Each basket has indication marks to assist in visually identifying the minimum acceptable level of NaTB to be added in the field. The basket mark indicating the minimum level is higher than the minimum required level associated with the specified TS minimum buffer mass, based on the minimum buffer density, which ensures sufficient buffer will be installed in containment.

NRC Request No. 7 A description of the test that will be performed to verify that the Na TB in the baskets provides adequate pH adjustment, according to the proposed sampling test #4 in the license amendment submission, Table 4.1-28, "Minimum Frequencies for Sampling Tests."

Dominion Energy Virginia Response A NaTB buffer sample will be taken from each of the seven baskets during each refueling outage (RFO). Using the sample, a known quantity of buffer will be added to a known quantity/concentration of borated water. The test will be satisfactory provided the resultant solution pH is 7.0 or greater. The mass of the NaTB added to the test is based on the initial prototypical pH adjustment / buffer testing that was previously performed in support of the buffer replacement.

NRC Request No. 8 Revisions to Final Safety Analysis Report Sections such as 6. 1 (General Description),

6.2.3.3 (Chemical Additives), and 6.3.1 (Spray System), which describe the use and characteristics of sodium hydroxide as the chemical additive.

Dominion Energy Virginia Response The proposed updates to the Surry Unit 1 and Unit 2 Updated Final Safety Analysis Report (UFSAR) to reflect the proposed changes described in the LAR are provided in Attachments 1 and 2, respectively. The UFSAR updates will be implemented in accordance with the design change update process associated with the design change packages implementing the removal of the CATs and the replacement of the containment sump buffer. The proposed Unit 1 UFSAR revision is an interim revision Page 8 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure that reflects the differences between Unit 1 and Unit 2 following the implementation of the Unit 1 modifications during the fall 2022 refueling outage (RFO). The Unit 2 UFSAR revision reflects the final plant configuration after the modifications have been completed for both units following the Unit 2 spring 2023 RFO. The Surry Unit 1 and 2 site Plot Plans in the UFSAR will also be revised to reflect the removal of the CAT at each unit.

NRC Request No. 9 A reference to the current GL 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized-Water Reactors" chemical effects assessment of record for Surry Units 1 and 2 that supports the license amendment's statement of reducing chemical precipitate, and a discussion, as appropriate, describing how this change may effect post-LOCA sump volumes.

Dominion Energy Virginia Response Generic Letter (GL) 2004-02 The Surry GL 2004-02 chemical effects analysis is summarized in Dominion Energy Virginia's letter to the NRC dated February 27, 2009 [ADAMS Accession No.

090641018]. A new calculation was developed in support of the CAT removal / buffer replacement design change to assess the impact on Surry's resolution of Generic Safety Issue (GSl)-191 / GL 2004-02 as a result of changing the buffer from sodium hydroxide to NaTB. The assessment was based on both industry literature and utilizing the existing chemical effects models to predict aluminum dissolution following buffer replacement. The design sump pH limits do not change with buffer replacement; however, the pH of the initial spray from the RWST is greatly reduced without adding NaOH. The reduction in the initial spray pH results in less aluminum dissolution and therefore less subsequent precipitation. The overall conclusion of the assessment is that the design basis strainer head loss testing that was performed using chemical precipitate quantities based on a sodium hydroxide buffer remains bounding for the use of the NaTB buffer.

Post-LOCA Sump Volume Discussion The CAT volume ranges from approximately 3,700 to 4,650 gallons but was not included in the minimum flood level used for the Emergency Core Cooling System (ECCS) net positive suction head (NPSH) analysis. Therefore, removal of the CAT does not impact the flood level used for the NPSH analysis. The maximum flood level analysis includes the volume of water from the CAT. The impact on maximum flood level of the total basket volume including solid NaTB (45 ft3 metal + chemical volume per basket) was evaluated. This evaluation accounts for the removal of the credited volume from the CAT, as well as the volume of water displaced by the addition of the Page 9 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure NaTB baskets. The addition of the total basket volume including solid NaTB is less than the volume from the CAT; therefore, it was determined the maximum flood level remains below the design basis value after buffer replacement.

NRC Request No. 10 General structural arrangement drawing(s) of the new containment chemical baskets documenting the basket support structure, including basket weight and basket design details.

Dominion Energy Virginia Response The NaTB baskets are designed of stainless steel (Type 304 SS) and have a frame with a fine mesh and perforated metal plate enclosure. The baskets are designed with four caster wheels (type 304 SS and 2205 Duplex SS) to facilitate the movement of the baskets during outages, if required. The baskets are designed with a raised bottom to provide additional surface area to dissolve the NaTB in sump water and to avoid loss of NaTB due to any inadvertent water spillage or leakage on the containment floor. The baskets include internal level indication used for inventory verification and ease of adding NaTB, as well as a removable cover w_hich is provided with a drip edge to ensure that accumulated leaks/condensate above the baskets are directed away from the NaTB inside the basket.

The weight of one filled NaTB basket is approximately 3,975 lbs., and the weight of one fully assembled empty NaTB basket is approximately 1,425 lbs.

A picture of baskets similar to the planned baskets is provided in Figure 3.

Figure 3 - NaTB Basket (Example)

Page 10 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure NRC Request No. 11 Objective evidence (data, calculations) to support the statement in the license amendment that "The design loads for the baskets are generated by combining the unfactored load effects of dead loading, chemical pressure loading, and seismic loading .. .[the] baskets were evaluated to maintain their structural integrity during a Design Basis Earthquake event concurrent with post LOCA elevated temperature conditions." This information should also state the applicable design code applied, applicable design loads, load combinations used for the design, a summary of computed stresses, and margins showing the structural integrity of the baskets.

Dominion Energy Virginia Response The basket members and connections are analyzed to meet applicable licensing and design basis requirements in the UFSAR and Dominion Energy Nuclear Engineering Standard (ONES) DNES-STD-CE-0046, AISC 9th Edition, "Manual of Steel Construction". In accordance with the AISC 9th Edition and UFSAR Section 15.2.4, Seismic Design, allowable stresses for members may be increased by 1/3 for earthquake loading using the applicable load combinations. When considering the 1/3 increase for earthquake loading, the maximum member interaction for members, connections, welds, wheels, bolts, and anchor bolts is less than the required 1.0. While not required, additional checks were conservatively performed on the members and connections using ASCE 8-90, ASCE 7-88, and Design Guide 24. In all cases, the additional checks satisfy the code requirements.

Justification for Non-safety - Quality (NSQ) Basket Design:

As a result of this modification, baskets are designed to hold the NaTB buffering agent and are to be placed in the Containment basement. The NaTB buffering agent, which is procured as Safety Related due to its function of providing pH control for the containment sump and to retain radioactive iodine in solution, can perform its design function without the presence of the baskets. Therefore, the purpose of the baskets is to contain the NaTB buffering agent. A failure modes and effects analysis was performed to demonstrate credible failure of the basket does not impede the NaTB buffering agent from performing its design function. Any buffering agent that was to escape from the basket would improve the dissolution rate.

DNES-AA-MEL-4001, "Determining the Safety Classification of Structures, Systems, and Components," has been reviewed to determine the safety classification of the baskets. Per DNES-AA-MEL-4001, Attachment 2, Code 5.2.6 and 5.2.26a, the baskets are classified as Non-safety Quality (NSQ) (i.e., components that are not safety related but have special quality/regulatory requirements). Code 5.2.6 is defined as, "Components that are NOT functionally safety related, but that are required to be seismically restrained, supported or anchored to prevent damage to nearby safety Page 11 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure related equipment." NSQ Code 5.2.26a is defined as, "Those components, systems, and structures that are NOT safety-related, but which are designed and installed as seismically qualified to ensure the required level of functionality during and/or after a DBE [Design Basis Event]. This definition includes components that are required to remain functional (i.e., some or all of their active and/or passive functions must remain intact) during and/or after a DBE. This requirement may be the result of a SAR/licensing commitment or just the desire to achieve enhanced reliability. This includes "active" components that must remain fully operational, as well as "active" and "passive" components that only have to maintain system pressure boundary." Per DNES-AA-MEL-4001, a Design Basis Event (DBE) includes the following: normal operation, anticipated operational occurrences/transients, design basis accidents, external events, and natural phenomena. Therefore, the baskets are designed to meet Seismic 11/1 requirements. Additionally, the baskets are designed to maintain their structural integrity during a DBE.

NRC Request No. 12 A discussion on the high energy lines in the vicinity of the baskets, and how the baskets are protected from HELB effects (jet impingement and pipe whip) is not included.

Dominion Energy Virginia Response To ensure the NaTB baskets are not adversely affected or adversely affect the containment sump strainers, the planned installation locations for the NaTB baskets have been chosen to avoid placement in areas that could be affected by HELB effects in the containment basement. Protection against the effects of blowdown jet forces and pipe whip resulting from a postulated pipe rupture of the Reactor Coolant, Pressurizer, Main Steam, and Feedwater System piping is provided by a combination of distance, restraints, and barriers. Specifically, high energy piping is protected / isolated by missile barriers and restrained to limit pipe whip. The baskets located in the containment annulus area are protected by the crane wall. Baskets that are not protected by the crane wall are located so that the impingement pressure from an HELB would not affect the baskets such that the ability of the NaTB buffer to perform its design function would be impeded based on the zone of influence (ZOI) radius. Therefore, the baskets are sufficiently protected from the effects of HELBs through the use of barriers, restraints, and distance.

Page 12 of 12

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure Attachment 1 PROPOSED SURRY UNIT 1 UFSAR UPDATE (INTERIM)

Virginia Electric and Power Company (Dominion Energy Virginia)

Surry Power Station Unit 1

Revision 50.0 1- Updated On Iine 10/31/18 P UF AR 5.3-4 installing the closed side of a spectacle flange. The maximum purge rate through this path is limited to 20,000 cfm as the filter also erves the Auxiliary Building eneral xhaust.

5.3.l.4 Design Evaluation Whenever the three main recirculation fan and coil units, the three CRDM fan and coil units, and the main coo lant pump coo ling systems are operating, the containment bulk air temperature will be maintained below 125°F. Two f the three fan in the recirc ulation system will continue to operate under limited main coolant leakage cond itions that result in containment pressure. up to but not exceeding the Consequence Limiting afeguard (CL ) high-high containment prcssur actuation setpoint ( ection 7.5 .1.2). The third fan wi ll continue to operate, if normal station power is availabl , until stopped either manually or by actuation of an electrical fault protecti n device. This may provide sufficient heat removal to permit reactor shutdown under limited leakage cond itions without re orting to c I t1 ray injection . .....-----.

REMOVE The inside containment filter units will remove the airborne iodine an par 1culate radioactivity that could result from nominal operational leakage during subatmospheric operations.

The purge system pr vides the capability to change the containment air and remove radioactivity, if required, before entry for refueling and maintenance. The purge system i design d for one air change per hour and to maintain a minimLJm of 60° inside the containment.

5.3.1.4.1 Incident ontrol During normal operation of the plant the conta inment purge y tern is not in u e.

After unit shutdown and coold wn, purging of the containment can take place. The purge exhaust air may be directed to either the non-safety-related or safety-related ventilation filters in the auxi liary building if fuel is being handled inside containment, but no :filtrati.on is credited in the analy i . The analysi

• of the fuel handling accident in containment does not require that containment integrity be e tablished prior to fuel movement. The purge de ign flow through the non-safety-related fi lter is 20,000 cfm with a limit of 30,000 din through the safety-related filters when containment integrity is established. If containment integrity is not e tablished, the maximum purge exhaust rat equals the maximum safety-re lated fan flow limit of 39,600 cfm.

The physical design and installation of the duct system preclude exceeding these limit . The discharge of the safety-related filters and non- afety-re lated filter are monitored by the same system for radioactivity prior to release. hould a LOCA signa l from the other unit be received, the air-operated isolation dampers will fail closed and allow the safety-related filters to treat the air exhausted from the ECCS areas. As described in ection 9. 13.4. 1, if a safety injection actuation occurs and auto alignment of the ventilation system is defeated, manual action is required to rea li gn the system to the ECCS filtration mode. An alarm is recejved in the main control room if the purge is not realigned fo ll wing a safety injection signal. This condition i not expected however, ince defeating the automatic realignment is no I nger credited in the fuel

Revision 51.05- Updated Online 07/30/20 SPS UFSAR 6-iv REPLACE Chapter 6: Engineered Safeguards 6.3-26a Figure 6.1-1 Unit 1 ngineered afeguards ystems .. . . . , . ...... ......... . . 6.1-4 Figure 6.1-2 Unit 2 Engi11eered afeguards ystems ....................... . 6.1-5 "igllre 6.2-1 afety Injection System . .......... ... .............. ....... . 6.2-55 Figure 6.2-2 Protection Prov ided by Various ombinations of afeguards Components ........ .. ..... .. ...... .. .... ... ... . 6.2-56 Figure 6.2-3 Avai lable NP H LH l Pump NP H Available Analysis ......... . 6.2-57 Figure 6.2-4 ontainment Pressure LHSI Pump NP H Avai lable Analysis ..... . 6.2-57 Containment emperatures H I Pump NP H Available Analysis. . 6.2-58 Total RSHX Heat Rate LI-ISi Pump NP H Available Analysis . . . . . 6.2-58 Unit l Recirculation Spray Subsystem . . . . . . . . . . . . . . . . . . . . . . . . 6.3-27 Unit 2 Recirculation pray ubsystem ............... . .... .. . . 6.3-28 Figure 6.3-4 Pip ing and ornponents Elevati ns pray Systems ...... . . . ..... . 6.3-29 Typical - General tructural and Piping Arrangement Recirculation pray and Low Head afety Injection Systems Outside the Reactor ontainment. . . ....... . .. .

Figure 6.3-6 Outside RS Pump NPSH Available Analysis D +IL at 10.3 psia, 25°F W .. ...... .......... ..... ...... . 6.3-31 Figure 6.3-7 Outside RS Pump NP H Available Ana lysis DEl L at l 0.3 psia, 25°F W .................. ........ ... . 6.3-3 1 Figure 6.3-8 Outside RS Pump NPSH Available Analysis DEHL at 10.3 psia, 25°F W ... ...... .. . . ................ . 6.3-32 Figure 6.3-9 Outside R Pump NPSH Available Analysis DEH G at 10.3 psia, 25°F W .. ............... . ... ... ..... . 6.3-32 Figure 6.3 -10 Inside RS Pump NP H Available Analy is DEP at 10.1 psia, 70°F SW .... ...... . .. . . ......... . ..... . 6.3-33 Figure 6.3- l l Inside RS Pump NPSH Available Analysi

• DEPSG at 10.1 psia, 70°F W .... ...... . .......... . ........ . 6.3-33 Figure 6.3-12 nside RS Pump P H Availab le Analysis DEP G at 10. 1 psia, 70°F W ............. ........... .. .. .. . 6.3-34 Figure 6.3-13 Inside RS pump NP H Available Analy i

• I* IO O I I It I I I I I*

• o *I , o I I I I Unit 2 ontainment Spray ubsystem . . . ... . . .. ... .. ..... .. . . .

INSERT

Revision 51.05- Updated Online 07/30/20 PS UFSAR 6.1-1 CHAPTER 6 ENGINEERED SAFEGUARDS 6.1 GENERAL DESCRIPTION Note: As required by the Renewed Operating icenses for Surry Units 1 and 2, issued March 20, 2003, various system structures, and components discussed within this chapter are subject to aging management. The programs and activities necessary t manage the aging of these systems, structures, and components are dlscu sed in hapter 18.

The eng.ineered safeguards, together with the containment ( hapter 5), protect the public and the station in the event of the design-basis accident, as defined in ections 14 .5 .1 .2 and 14.5.5. The engineered afeguards are design d to minimize the accident by performing the fol lowing three functions:

1. Supply borated water to the reactor coolant system t cool the core, decrease reactivity , Jim it fuel rod claddin g temperature , limit the metal-water reaction, and ens ure that the core remains intact.

2. Limit the driving p tential, including differential pressure and time duration, for leakage out of the containment structure.

3. Reduce the concentration of airborne fission products avai lable for leakage.

The first function is satisfied by the timely, continuous, and adequate supply of borated water to the r actor coolant system and the reactor core. he second function is satisfied by the provision of heat sinks for the condensation of steam released inside the containment, the inherent depressmization of the containment below atmospheric pressure following the de ign-basis accident, and means for maintaining th c ntainment at subatmospheric condition for an extended period of time. The third function is satisfied by provi.ding chemical additiv (NaO.E )

to the containmen to enhance the spray removal of radioactive iodine f*

INSERT and

1. A safety inj ection system (

reactor coolant loops.

2. Two separate low-head safety injection sub ystems, either of which provides long-term removal of decay heat from the reactor core.

3. Two sepatate subsystems of the spray system (containment spray and recirculation spray) that operate together to reduce the containment temperature, return the containment pressure to subatmospheric, and remove heat from the containment. The recirculation spray subsy tern maintain the containment subatmo pheric and transfers heat from the containment to the service water system (Section 9.9).

Revision 51.05- pdated Online 07/30/20 P UF AR 6.1-2 A composite schematic diagram of the engineered safeguards systems is h wn in Figures 6.1-1 and 6.1 -2 fi r Units l and 2 *e p ctively.

The safety injection system provides for the charging of borated water to the reactor coolant system from the accumulators following a LO A. The three accumulators are self-contained and are designed to supply water as soon as the reactor c olant system pres ure drops below 600 psig.

Additional makeup to the reactor coolant system is provided by the charging pumps, operating in the safety injection mode, and the low-head safety injection pumps. Both the charging and low-head safety injection pumps are located out ide the containment, are driven by an electric motor, are capable of being rapidly energized or operated, and are powered from the emergency power buses. The pumps also ensure an adequate supply of borated water for an extended period of time by recircu.lating water from the containment sump to the reactor core through two separate flow paths.

The containment spray subsystem supplies chilled borated water to the conta inm ent immediately following the receipt of the safeguards initiation signa l. This ubsystem includes two full-capacity, electric-motor-driven containment spray pumps that are located outside the containment and are supp li ed with power from the emergency buse . The containment spray pumps supply chilled water from the refueling water storage tank to the containment. Either pump is capable of furnishing sufficient spray water to prevent overpressurizing the containment strncture. A chemical addition tank is balanced hydraulically with the refueling water storage tank and provides a flow of sodium hydroxide solution to increase the alka linity of the containment INSERT spray and recirculated pray to ensure effective removal of radioactive iodine The recirculation spray subsystem recirculates water from the containment sumps

• rough service-water-cooled recirculation spray heat exchangers to the recirculation spray headers. Two of the four 50% design capacity, motor-driven recircu lation pray pumps are located outside the containment. All four of the recirculation spray coo lers are located in ide the containment and transfer conta inment heat to the service water system ( ection 9.9).

The containment spray and reci rculation spray subsyste s arc capab le of reducing the containment pressure to subatmo pheric in less than 60 minute , thu terminating all outleakage to the environment. Thi original design criterion was modifie in conjunction with the analyses for implementation f the alternative ource term. The modi 1ed criteria requ ire that, fo ll owing the LOCA, the containment pres ure be less than 1.0 psig ithin 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and less than 0.0 psig within 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> . he radiological c n equences analysis de onstrate acceptable results provided the containment pre sure does not exceed 1.0 psig for the * . terval from 1 to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> following the Design Basis Accident. Beyond 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> , containment pre sure is assumed to be le s than 0.0 psig, terminating leakage from containment.

INSERT The containment vacuum system removes ny ubsequent air inleakage after the containment pressure has been reduced to subatmos heric. Because of the inherent low-leakage design f the containment, the use of the vacuum p mps will probab.ly not be required for several odium Tetraborate Dccahydr te (NaTB) is torcd in baskets in ide ntainment to increase the alkalinity of the surnp water produc d during an event which exceeds the L high-high containment pressure actuation setpoint. The NaTB solution is recirculated by the recircul ation spray subsy tem t ensme effective remova l of radioactive iodine (Unit 1).

a * * *

• I l * ~ I ._ 1. .. fl. \. L L L. 1. ... t,._ .L .t.. i,_ .. --" J,._ J,_ _j,_ J.. J,.. .J..._ .J.......L......L..

REPLACE WITH INSERT A Figure 6.1-1 T 1 E GINEERED SAFEG ' ARDS SYSTEMS I

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j i~:: - ..........:=~~~=~+.----r.i~--'

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LOCAL Wl)S s.u&U REI:IRClUJ1CtlSl'RAY C00t.ERli IOCITE: R

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51-f:OWNOMnlSMA.tftNGIS TTRCAI..ROHERTHAN AC1U\l J..ECE!ll SPS RCS - REACTO'R COCLIIMT S"YSTI3I 06/11/18 Plfl'IGffl)!l'~ , . _ T O L>T.l'IT 'M)S-'dASTE DISPOSAL SYSiB1 Se.Ellll1lZIJfTB 15 ~ 'WJt.UllPED AND 81.AED llllEN FOOT YllC-"9:lHTLQIJ)QEICVAtl/E nlCIC RE1Nr0RCB)COHCS;Eff CQHtA,H1811' 11At.

Rcvi ion 5 1.05- Updated nlinc 07/30/20 P lJF /\R 6.2-15 Thefo /lo*w ing information is HL TORI 'AL and is not intended or expected to be updated for the life of the plant.

I. Two pr duction line motors were used fo r this test. ne was exposed to a total f 1.5 x 10 8 rad of gamma radiation in approximately one month. The other motor wa used ti r the final comparative analysis.

2. Both moto rs wer tested for coil resistance by the Wheatstone bridge method, and for insulation r istance by meggering both befi re and after motor vibrati n and rever ing operation .

• ** *

• I with a po taccident solution of boric acid and REPLACE he recircu containment is maintained wet to pr vide a wat I to reduce the potent ock in g the LH I pumps co ntainment sucti V'

( eferen e 9).

odium hydroxide and b ri acid and sodium tetrab rate decahydrat i discu sed 6.2.2.2.5 in W AP-7153 (Refer n e I 2) and W AP- 16596 (Reference 13), re pectiv ly.

The stainless tecl manual. globe, gate, and ch ck va lves are de igned and bui lt in accordan e w ith the l'equiremcnt outlin ed in the motor-operated valve description above

( ction 6.2.2.2.4).

The carbon steel va lves ar built to confo1*m with U A Bl6.5. The material of construction of th body bonnet, and disk conform to the requirements of A TM Al 05, rade 11; A 181 , rade ll ; orA2 16, radcW or W h ca rb 11 tel valve pass on ly 11011-radioa tive gases and were ubject d to hydrostatic test as utlined in M - P-61 except that the test pres ure was maintained for at least 30 minutes.

6.2.2.2.6 Vent Valve f igh point vents have been installed at critical points in the suction Iines of the charging (I [H T) pumps, and the di charg lines of the LH I pump where ga ould collect.

6.2.2.2.7 Accumulato r heck Valves The pre ure-containing part of the e va lve a emblies are de igned in ace rdance with M S P-66. Parts in c ntact with the operatin g rluid are of auste nitic stainless stee l or f quival nt corr s ion-re istant material pr ured to app li cab l A TM or Westinghouse spec ifications.

Revision 5 LOS- Updated nline 07/30/20 6.2-24 The three com binations (Bar A, B, and ) reprc ent degraded ca e with operation of less than the in tail ed emergency core cooling equ ipment. These cases are shown only to pr sent the capability f individual p rti n of the ystem and to demon trate the overall margins of the system. The operation of on safety inj ection charging pump together with two accumulators is probably capab l f providing protecti n over a con iderab ly greater rang than sh wn. Howev r the analysis ha on ly considered breaks up to the 8- inch diameter.

Ba t* D, which is the combination of the afety equipment in Bar and , and which also repre ents the minimum engineered afeguard ava ilable automatically, provides protection as hown ov r the complete range of break size up to and including the omplet circumfer ntial fracture of a r actor coolant pipe.

For the small range of brcal sizes up to 2 inche , a hown in ar A, the action of one afety inje tion chargi ng pump acting alone is suffic ient to maintain nough core water inventory to ensure continued c re cooling.

6.2.3.2 Borated Water Injection hemistry During the inj ection of emergency cooling water into th reactor coo lant sy tem fo llowing a LO A, the concentration of b ron will vary depending n the dcpre. urization hi tory of he reactor. If depre surizat ion were slow, the hi gh- head pumps would inj ec t boric acid at a concentration greater than 23 00 ppm, which would be d.iluted by the c lant remain ing in the system. Rapid depre surization would bring about early injecti n f water containing oric acid at a c ncentration greater than 225 0 ppm from the accumulators. When rec ircul ation begins, the average concentration of boric acid is (and will remain) at a concentration that will maintain the core ubcritical.

The concentrations of other materials, including chlorides are quit low in th is olution corrosion products being generally inso lubl e in a basic so lution. Assuming 50% of the maximum core inventory is released to containment after a A the principal fi i n product in the ump (assuming a gro core fa ilure) wou ld be iodine at a range between appr ximately 1.6 to 1.9 ppm for 500 day f operation and appr ximately 3.0 to 3.6 ppm for I 000 days of peration. The temperature of the sump water is reduced below 150° , under normal operating conditions with a minimum of two recirculation c oler in operation, after a relatively short period of time i.e. a few h urs). Below 150°F chi rid r l ---------

REPLACE 6.2.3.3 hcrnica l Additive ontainm nl tra

• ontainment sp having a pH between ,,__..._._.,.._.__,.__..,, ill be use ......,.,.__,....,...,,_.....,.......,.,__,.__,,...,......, ours if minimum safeguard operate an 50 minute if norm al safeguard operate. During this period, the conta.inment will be coo ling from 280° to appr , imately 140°F . At th end of the init ial containment co lin g period, lastin g no longe r than appr ximate ly one hour, the recirculation spray system will continue in service fo r an indefi nite period ; however the pH of the

INSERT box and italicized text SPS U SAR .--- --. 6.2-25 INSERT during the long-term postaccidenl period RE MOVE re mg spray and furth dition of chem additive is not contemplated.

The following information is only applicable lo Unit 2.

od ium hydroxide is normally stored for many industria l applications in atmo pheric-vented tanks. Reaction of sodium hydroxide with atmospheric carbon dioxide to form a large precip itate does not occur. However, to elimin ate particulate matter from any p tential source, the containment spray subsy tern includes a , tra iner on the suction side of the conta inm ent spray pumps. This strainer will have openings sma ll er than the mallest spray nozzles, and therefore wil l remove any particulate matter from the containment spray flow that might prevent the system from functioning.

To illustrate the remoteness of a 0 2 + NaOH reaction, calculations were made based on the following assumpti ns:

J. The tank temperature varies from 35° to 95°F each day, causing the tank to breath

2. All 2 entering the tanl reacts with the caustic.

The calculation indicate that this process must continue for 90 years to react with 1% of the stored caustic. Thi reaction would n t cause a precipitate to form.

Based on past perating experience and ca lculational results, a sod ium carbonate precipitate cannot form; therefore the functloning of the system wi II not be impaired because of precipitation.

The major construction materials that wi ll be exposed to the containment spray and the corros ion or deterioration rates ore ch under maximum exposure conditions, are_........-."?-"l'-,.,_

Table 6.2-7. - -- - - containment rial s adversely affected by t pray are aluminum and zinc.

\....l....>...A..>..A.A.>...>...iV...fYY'Y'V""V°Y"'lr--t'"<"Y'""'\

rature expo 'Ure cond ition under which these materials will be exposed to spray are from approximately 50 minute to 11/2 hours with the temperature

............,.,...._,.._~~~-.< to 140° . .

The materials will also be exposed to the recirculation prays, which have a pH between 7.0 and 9.0 for the postaccident recirculation period with the temperature at approximately 140°F.

The con equence of corrosion and/or deterioration on materials with regard to postaccident operation of the engineered safeguards is negli gible because components of the engineered safeguards are con tructed of stainless steel. REMOVE The corrosion rate f stainless steel is low enough in the spray olution to be of no practical concern (Reference 1).

Insert B The following iriformalion is only applicable to Unit 1 odium Tetrnborale Decahydrate stored inside containment i a white crystalline chemical in granular form. The NaTB is stored inside ba ket which contain the chemical until it is dissolved by the containment ump water. To eliminate particu late matter from any potential source, the containment spray subsy tern includes a trainer on the suction side of the containment spray pumps. This trainer will have openings smaller than the smallest spray nozzles, and therefore wi II remove any particulate matter from the containment spray flow that might prevent the system from functioning. Additionally, using NaTB as a buffer docs not result in any different precipitates than those that form with the original NaOH buffer and the amount of precipitates is reduced, resulting in lower strainer head losses. Therefore, the functioning of the system will not be impaired because of precipitation.

Revision 51.05- Updated nline 07/30/20 P UF AR 6.2-49 Table 6.2-7 N TRU Tl N MAT ~RJAL XP UR T ONTAINMENT PRAY Material arbon steel b 0.0 tainless st el 0.0 oncrete b 0.0 Mineral w ol 0.0 alcium ilicate and nibestos 0.0 Alumi num 12.0 mg/dm 2/hr Zinc (paint and ga lvan izing on teel) 0.04 mg/dm 2/hr c 7REPLACE 1 opper 0.0 90-10 copper nickel 0.0 P lyethylene and neoprene 0.0 he maximum total durati spray ystem is approximately 60 minutes.

a. e s than l mil/yr consider d to b zero corrosion rate.

b. Painted with orlar Epoxy hem ical Resi tant Enamel, which is a p lyamide catalyzed epoxy re in _paint.

c. orro ion rate at 140° , maximum xposure temperatuJe aft r 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. Aluminum has corr sion rate of le s than 800 mg/dm 2/hr at peak temperature.

Revision 51.05- Updated Online 07/30/20 P UF AR 6.3-1 6.3 ONSEQUENCE-LIMITING AFEGUARD 6.3.1 Spray ystem 6.3 .1.1 Design Bases The spray system consists of the containment spray subsystem and the recirculation spray subsystem, which are designed to provide the necessary cooling and depressurization of the containment after any LOCA. pray sy tern component data are given in Table 6.3- 1.

afety related components, piping, valves, and supports in the pray system are Sei smic ategory J.

The subsystems, operating together, cool and depressurize the containment to ubatmospheric pre sure following the design-basis accident.

The recirculation sub ystem is, in addition, capable of maintaining the subatmospheric pressure in the containment for an extended period following the design-basis accident.

INSERT he removal of radioactive iodine from the conta inment atmosphere after a design-basis accident is accompl ished through the addition of sod ium hydroxide so.lution to the containment spray (Section 14.5.4).

r-r.,....,,.....,,...,.,.....,....._

INSERT The spray system is designed depres urize the containment to ubatmospheric pressure any one of the two containment * *

• recircu lati spray pump operating. tc into the containment on spray ubsystem 6.3.1.2 Spray System Components he spray system is designed, faWM?o-!S't'iWl"---tA~!ti<"M:IT1'-'"!:r1'1'7'M'l'l'M'l:r'l11~f'N",!'91't.:'r;!t-4"K'r.s'"'l'?.rl"h"l'T1'1'1?rll,ri'~-----,,....,..--

of the eneral Design riteria, as discussed in

• ecti n 1.4 . The spray subsystems and their components are considered to be essential t acc ident prevention and/or the mitigation of accident consequences that could affect the public health and safety.

6.3. 1.2.1 Pumps and Valves The pray pumps and valves are fabricated, welded, and inspected acco1*ding to the requirements of the applicable portions of the A M ode, ections HJ , VJIT and IX. Materials of construction are stain le s steel or equivalent corrosion-res istant materials.

Valve packing and pump seals are selected to m.inimi ze or el iminate leakage where necessary. Motor-operated valve operators are selected because their proven superior reliability in past applications ensures reliable valve operation under incident conditions.

The Teflon leeve and packing of the outside recirculation pray system suction va.lves have been changed to XOMOX 7. Th is change reflects the review performed in accordance with NU .. -0578, Section 2. 1.6.b. ln this review .it wa found that the valves would be located in a

Revision 51.05- Updated Online 07/30/20 PS UFSAR 6.3-2 high-radiation area as a result of a

• CA. The Teflon material is satisfactol'y to only I x 104 rads, whereas the XOMOX 7 material is satisfactory to 8 x 106 rads. Th expected 60-year normal plus postacc ident integrated radiation dose in this area is conservatively estimated not to exceed 8 x 106 rads.

REPLACE The containment spray system piping and equipment are fabricated of A M A358, Type 304 stain less steel, or equivalent, which has a corrosion rat of less than 0.0001 in/yr at the

,....,rv-'v-..,.........-il"~!,ffi-,~~ltM..e01~~~~~'c-'rel'"'81iffii~ an 8.7 to 10.4 H.

4. REPLAC E ipment are also fabricated f Type 304 or Type 316L stainless steel, or equivalent, except for the Recirculation pray Heat Exchanger (R HX) tubin i *

• anium and th ,......,....,..._,~--.. .

• h are brass. stem operating ostaccident 7.0 to 9.0 p (Unit I) and 7.7 to 8.5 pH Unit 2)

-rosion er f austenitic tain . is inhibited i

-...,...;~........>-..>..>..>...>..,>,..,>,...>,~-

tions in the hypothetical environment after the design-basis

\ - - - - - - - - -- 1REPLACE p a eat a relative ly low pressure of approximate ly 100 psi gauge and are not highly stre ed during operation, so that the inducement toward cracking is reduced .

ecause t 1e p I of the c ntainment spray elution is a ove . an the recirculation spray solut ion pH is essentia lly 8.0, the potentia l for caustic stress corrosion cracking in the stem and recircu lation s ra system i" virtual! nonex i tent.

The p tential for caustic tress corro ion cracking in the containmen t spray system and recirculation spray system i

• virtually noncxist nt because of the fi II wing:

1. The short duration of containment spray system operation (Un it I) r

2. Th pH of the containment spray solution is above 7.0 (Unit 2) is such that n

3. The recirculation spray olution pH i above 7.0 during the I ng-term postaccident Windit period (Unit I and Unit 2) ca lculated to occur un

• er esign-basis acci motors located inside containment.

REPLACE The containment motors have been selected to ensure operation during O A conditions.

Motor electrical insulati n is in accordance with ANSI, l ~ , and NEMA standards. The motors are tested as required by these standards. Bearings are anti friction type. Bearing loading and high-temperature tests have been performed, and the expected bearing life equals, or exceeds, that specified by the Anti Friction Bearing Manufacturers Associati n (AFBMA).

6.3.1.2.3 Piping Pip ing fabrication, installation, and testing are in accordance with the peciftcation for P wer Plant Piping, ANSI B31.1, with supplemental requirements and in pections as nece sary

Revision 51.05- Updated nl.ine 07/30/20 P UFSAR 6.3-4 he suction lines between the containment ump and the R pumps are cross connected.

This design feature was originally provided to ensure a supply of water to each pump in the event that the suction of either pump become clogged. The current common header strainers that protect the pump uction lines are designed to withstand the full debris load that could be generated by a LO A.

The design data of the spray system components are given in Table 6.3-1 .

6.3.1.3 De cription 6.3.1.3.l ontainment Spray ystem The containment spray system consists of two completely separate trains of spray rings located in the containmenl dome and one c mmon spray ring located outside the crane wall. Each lrain is rated at 100% capacity. The recirculation spray sy tern is compo ed of two trains, each consisting of an in side recirculation spray ubsystem and an outside recirculation spray sub ystem. ach subsystem is approximately 50% capacity and consists of one recirculation spray pump, one recircuJation spray heat exchanger (R BX), and one 180° coverage spray header with nozzles. REPLACE An add it ional ring header common to both containment spray trains is installed at ~ levation 95 ft. 6 in . outside the crane wall. heck valves are installed in each branch connection from the riser to the common header to limit fill time, should on~~~~~~~~~,'i,J-,~i.,w.,.~~N"'..,,...,,..-1-v....,...,....,-_

start. . - Jb (Unit 2)

The c ntainment spray subsystem is shown i Figur 6.3- I and the recirculation spray subsystem is shown in Figure 6.3-2 . levations of al l piping and compon nts of these subsystems are shown in igure 6.3-4. (Unit 2 only) INSERT---~.

~ ach of the con mment spray ea ers draws water independen y *0 1 t e re ueling water storage tank. The odium hydroxide so lution used for iodine rem val fl om the containment atmosphere is

• aed to the containment spray water by a balanced gravity fi ed from the chemical addition tan . he refueling water storage tank is a vertical cy linder with at at bottom and a dome top, and i seemed to a reini reed-concrete foundation. The refueling ater storage tank i fabricated of A TM A240, Type 304L stainl ss steel, in accordance wi h API TD-650. The requirements for welding, welding procedures, welder qualification, wel point efficiency, and weld inspecti n are in accordance with Section IX of the A ME Code the pecification for Fie ld Fabricated Storage Ta11ks (Reference 4). The chemical addition tank is a vertical cylindrical vessel wilh flanged and di hed heads mounted on a skirt and secured to the reinforced concrete foundation. The chemical addition tank is fabr icated of A TM A240, Type 304 stai nless steel in accordance with ection VIIl of the A ME Code.

Both tanks are designed as Clas I components, as described in Section 2.5 , to withstand design seismic loading in accordance with the design tress criteria of A M ~ ode ection Ilf, Figure N-414, Nuclear Vessels. The connecting piping is designed to withstand seism ic loading to

Revision 51.05- Updated Online 07/30/20 P UFSAR 6.3-5 ensur the functioning of the system. The refueling water torage tank is provided with a manhole for inspection acce, s.

Prior to unit operation, the wat 1* in the refueling water storage tank is co led to a temperature of sl ightly below 45 °F by either circulating the water through a heat exchanger that use chi lled water from the chi I led water subsystem of the c mponent cooling system

( ecti on 9.4) or by using mechanical refrigeration units. M chanica l refrigeration units then maintain the tank water below 45°F. The tank is insulated. The refueling water storage tank also has a .nozzle connection that supplies water to the safety injection system ( e tion 6.2).

The refueling water storage tank (RW T) is a pas ive component and is required on ly during a sh rt period follow ing an accident. It is prov ided with four channels of level indication, which provide s ignals to level indicators. The leve l indication range for t he RWST is app roximately 14,000 gallons at 0% level to approx imately 399,000 gallons at 100% level. The RW Tis maintained at greater than 387 100 gallons of borated water at or below a temperatur of 45°F during normal plant power operations. Level transmitters prnvide input to a low level alarm and an empty alarm when RWST level drops below thes respective sctpo ints. When two of fou r channels have sensed a low RW T level condition>an interlock signa l is generated to allow for the tart of the TR and ORS pumps on a H.i-Hi Actuation. Additionally, when two of four channe ls have sensed a low- low RW T level condition, a ignal is generated to realign safety injection to the recirculation mode automatica lly. It takes approximate ly three minutes to realign the valves from inj ction to recirculation mode. The I ey values for the RW T as urned in the safety analysis are presented in Ta ble 5.4- 17. The safety analysis values are conservative with respect to plant operation. INS ERT The chemical addition tank 1s ocatea c se to the refueling water storage tank. The normal perating capac ity of the AT, including in trnment uncertainties, is greater than the minimum CAT volume of 3800 gallons assumed in the safety analysis. Flow f the sodium hydroxide solution is from the chemical addition tank directly t the containment spray pump suction via a cau tic addition line. Th is flow path provides for a red uced caustic transit time and introduces the caustic at an e entially constant rate. The c nstant addition rate r,rovides for a more constant spray pH _during the vari u modes of_ afeguards.system operatio~ IN.S E.RT I A line from the chemical add1t1on tank c1rculatmg pump 1s installed to permit periodic circulation of caustic so lu tion in the piping and maintain the capability of recirculating the chemical addition tank.

INSERT The chemical addition tank: LS msu a e an t e recirculation line i electrically heat traced to keep the tank and recirculation line contents at a temperature wel I above the freezing point of the chemical spray olution. The chemical addition tank has a I w-temperature alarm set at 35°F.

The containment spray p~1rnp are capable of upplying approximately 3200 gpm of borated water to two eparate circular containment spray ring header* located approximately 96 feet above the operating floor in the dome of the containment structure and the common crane wall

Revision 51.05- Updated Online 07/30/20 P UF AR 6.3-13 de ermined to be ufficient such that under full debri loading cond itions there would b adequate N II available to the R and Lil I pumps during accident conditions.

INSERT 6.3. 1.4.2 Recirculation pray Nozzles The pray sy t m consi t f two cparate but para II I containment spray ring located in the containment dome and one common containment pray ring located out ide the crane wall, plus£ ur separate but parallel recirculation spray headers each of approximately 50% capa ity.

The use of a cparate spray header c nnected to the di charge of each pump results in a fixed flow rate, and all ws for optimized se lectio n f spray n zz le sizes. Thi arrangement gives the optimum ombination of sma ll pray particles for maximum heat transfer and larg r particles f r better c verage towa rd the center and .ides of the conta inment. In addition, thi arrangement al o ensure that a failure of a component in any ne sub y tern d es not affect the operational capab ility of the other sub ystems.

The methods of preventing the plugging of pray nozzles in the two systems vary. For each containment spray train, the mate *ial of con truction, a well as the pump suction fi lter, prevent nozzle plugging. A method of n zzle testing is provided in the refue ling water storage tank t ensure that no particulate that could plug the containment spray nozzles coll ct in the tank.

espite this precaution and regardles of strainer perforation size, some types of particle cou ld conceivably pass lengthwise through the strain rand cau e logging of a spray nozzle. lowever, ince the stra iner perforation are maller than th ma ll e t pray nozzle open in g such an occ urrence is cons.idered to be highly impr bable.

The containment sump strainer assembly i de igned uch that a single assembly provide filtered b rated water to all fou r y *tern pump , a discus ed in ection 6.3.1.3 . The d sign feature of the strainer prevents complete failu re of all suction points of the R ystem. Th trainers are rais d off of the floor, which prev nts large d bris (non-buoyant) from reaching the fin and blocking them. Tt provides significantly large area of fin perforati ns that reduces the approach velocity and possibility of the trainer becoming c mpletely bl eked.

ince the redundant capacity of the recirculation spray subsystems increase. from 100%

after a I -of-coo lant incident to 400% to 1000% J day after an incident, plugging that could on ly occur on a long-term basis w uld have n significant effect n the capability of the ubsy tems.

6.3.1.4.3 Recirculation pray Heat ~xchanger Initia lly, the heat exchangers of the recirculation spray trains are clea n and dry with maximum heat tran fer capab il ity. For long~term operation, on the ord r of week or months, there may be some fouling of the tubes on the servic water side, with resultant los in heat

Revision 51.05- Updated Online 07/30/20 PS UF AR 6.3- 18 The recirculation pray subsystem n zzles will be subject to an inspection or smoke or air test fo llowing maintenance or an activity which could cause blockage to prnvide indication that p lu gging of the nozz les has not occu1Ted. The te ting of system controls is dis ussed in tion 7.5.

Electrical insulation resistance te ts are performed during the lifetime of the RS motor to verify the integrity of the insulation. Periodic tests are also performed to nsure th motors remain in a reliabl operating condition.

The Recirculation pray y *tern is subject to the applicable inservice inspection and in ervice testing requirements fthe A M ode, as required by 10 FR 50 (Code of Federal Regulations, Title I 0, Part 50).

6.3 REFEREN ES

1. NR ulletin No. 93-02: Debris Plugging of Emergency ore Cooling uction Strainers, dated May 11, 1993.

2. Letter from Virginia Electric and Power Company to the NRC, dated June 10, 1993, erial No. 93 -3 07, Re ponse to NR Bulletin 93-02.

3. etter from Virginia ~ lectric and Power Company to U NR dated February 7, l 996 ( erial N . 95-566A) , Generic Letter 95 -07 Pressure Locking and The,-ma/ Binding of Safety-Related Power-Operated Gate Valves, Surry and North Anna Power Station.

4. tone & Webster pecification NU -258, Specification for Field Fabricated Storage Tanks, Revi ion 2.

5. NR Generic Letter G 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized Water Reactors, dated eptember 13, 2004.

6. Nuclear nergy Institute (NEI) Document N 1 04-07, Pressurized Water Reactor ump Pe1formance Evaluation Methodology dated ecember 2004.

7. afety Evaluation by the Office of Nuclear Reactor Regulation Related to NRC eneric Letter 2004-02, Nuclear Energy Institute Guidance Report Pressurized Water Reactor ump Performance Evaluation Methodology.

8. Letter from Dominion Resources Inc. to the NR , dated eptember l , 2005, el'ial No.05-212, Respon e to NR eneric Letter 2004-02.

9. Westinghouse Document WCAP-16406-P, Revision 1, Downstream Wear Evaluation

~Methodology for ontainment Sump creens in Pressurized Water Reactors.

10. Westinghouse Document W AP-16793-NP, Revision 0, Evaluation ofLong-Term ooling Considering Particulate, Fibrous and hemical Debris in the Recirculating luid.

ADD rnsert

Insert I l. U. . uclear Regulatory Commission tandard Review Plan UREG-0800, Chapler 6, Section 6.1 .1, Rev 2, Engineered Safety Features Materials.

12. WCA P- 7153, investigation of l,emical Additives for Reactor ontainment Sprays, dated March 1968.

13 . W AP-16596-NP Revision 0, Evaluation ofAltemative Emergency Core Cooling System Buffering Agents, dated July 2006.

Revision 5 I .OS- Updated Online 07/30/20 PS UFSAR 6.3-21 Table 6.3- 1 ( NTINUED)

SPRAY SY T ~M OMPON NT DATA Chemical Addition Tank (Unit 2 only)

Number ~...,._,...,.._,,.~-...........'-(2 REPLACE Type Vertical cylindrical apacity INSERT 4311 gal Design pre ure 25 psig Design temperature l50°F Material 304 esign code A ME Section Vlll Operating pressure Atmospheric Operating temperature Ambient NaOH concentration hcmical Addition Tank Pump Number 17-18%

REPLACE Type Vertical centrifugal Rated f1 w 50 gpm Rated head INSERT 7 ft Theoretical horsepower 0.l hp eal Mechanical Design pres ure 225 psig Material Pump casing 316 haft AE 4140 Impeller S 316 Recirculation pray ystem trainer Assembly Number l (for both ORS and TR ystems)

Material S 304 Design ode A ME ection IJl, Subsection NF, lass 3 Structural DP 9.0 p id Perforations 0.0625 in. diameter perating Pressure 9.0-59.7 psia Operating Temperature 75-280°F

• luid Flowing Borated water Piping ADD Piping is designed to the Code for Pre sure Piping, AN I B3 l..l.

Insert Valves Recirculation pray system valves are designed in accordance with AN I B 16.5, Steel Piping Flanges and Flanged Fittings, or AN I B16.34, tee] Butt-Welded nd Valves.

Insert D Sodium Tetraboratc Decahyd rate Baskets (Unit I only)

Number 7 Material Basket SS 304 Wheels Dup lex S 2205 Nom inal ize (internal dimens ions) 6 fl X 5 ft X 1.5 ft Operating Pressure 9.0-59.7 psia Operating Temperature 75-280°F Technical Specification minimum 10760 lbm hemical Grade SQ Granular hemical peciflcation 8 20 3 36.5-38.3%

Equivalen t Na284O1* I0H2O 99.9-I05.0%

Na2O 16.2-17 . 1%

SO4 ~ 3.0 ppm Cl ~ 0.4 ppm Fe ~ 2.0 ppm Chem ical Sieve Specification Standard No.

Retained

REPLACE INSERT REPLACE WITH INSERT E

~

co en 0

INSlOE REACTOR OUTSIDE REACTOR V'I CONTAlNtlENT CONTAINM.EHT REFUELING \YATER STORAGETANK 0 Vo 2-:160° SPRAY HEADERS CHEP~ICAL ADDITION b

"u a.

TANK to

~

a.

0 2.

2 - REFUELING WATER CHEMICAL ADDITION 2- RECIRCULATION TANK PUMPS PUMPS 2 - MECHANICAL REFRIGERATION UNITS FOR C/.l TEMPERATURE '"O C/.l c"Tj NOTES:

Fe WLC -WEIGKT LOADED CHECK VALVE

• TO CHECK OPERATION OFWLC R'IVST INSTRUMENTATION SHOWN ,oN THIS BLEED FLO\//

DRAWlNG IS TYPICAL RATHER THAN ACTUAL DRAIN AC CONTAIN ENT SPRAYPU PS 0

0

(')

0

(!)

0

(/)

BLEED FLOW DRAIN 00 REPLACE

I ,NSERT EI IHSJDE REACTOR OUTSIDE REACTOR CONTAIN ENT CONTA! MENT REFUELING WATER STORAGE TANK I

2-360° SPRAY HEADERS I

l I

I I

I I 2

• MECHANICAL REFRIGERATION I U ITS FOR lcMPERATlJRE I

~ WLC Il NOTES:

WLC--WEJGHT LOADED CHECK VALVE TO CHECK OPERATION OF WLC BLEED FLOY/ R '/ST INSTRU ENTATION SHOWN ON THIS DRAIN I DRAWING IS TYP1CAL RATHER THAN ACTUAL I

t-----.----vi- WLC-- I BLEED FLOW DRAIN 1

I ADD NEW FIGURE 6.3-1b ON NEW PAGE 6.3-26b AFTER FIGURE 6.3-1a Figure 6.3-1 b UN1T2CO TAINME TSPRAYSUBSYSTEM INSIDE REACTOR OUTSIDE REACTOR CONTAlNtlSNT CONTAINMENT REFUEUNG IVATER STORAGE TANK 2

• 360° SPRAY HEADERS CHEMICAL C ADDITION '"O 0.

TANK

~

Cll c..

2

• REFUELING WATER CHEMICAL ADDITION 2* RECIRCULAl!ON TIU-IKPUllPS PU PS 2 - MECHANICAL REPRIGERATION UNITS FOR TEI.IPERAT!JRE NOTES:

WlC

• VIEIGHT L OADED CHECK VALVE

• TO CHECK OPERATION OF\'ILC RV/ST INSTRUMENTATION SHOWN ON THIS BLEED FLOW DRAWi G ISTYPJCAL RATHER THAN ACTUAL DRAJN 0

0

(')

g0 WLC Cl}

BLEED FL<:JN DRAIN

Table 7.5-2 (CO T UED)

VALVES/DAMPER AC ATED BYE GINEERED SAFEGUARDS SIG ALS [I) 0 Function Override/Bypass  ;:;

V, 2-CS-MOV-202Ad REPLACE (Actuated (Override or 0

Designation (Valve or 2-CS-M OV-202Bd Valve or Signal bypass condition V, Damper Tag o.)

(Similar for Unit 2)

Service (Actua d Valve or Damper Description)

Damper Position)

(Actuation Signal) following actuation) b

-0 Cl..

1-CS-MOV-l OJA Con pray pump A discharge isolation val e Open CLS-HiHi one .....

~

~

C.

l-CS-MOV-10 1B a C t spray pump A discharge isolation valve Open CLS-HiHi one 0

s I-CS-MOV-101C a ont spray pump B discharge isolation valve Open CLS-HiHi one 5-1-CS-MOV-IOID a Cont spray pump B discharge isolation valve Open CLS-HiHi one 0 l -CS-MOV-102A a l-CS-MOV-102B a Cont spray chem add tank isolation valve Cont spray chem add tank isolation valve Open Open CLS-Hiffi CLS-HiHi one one 0

-....:i l ,.J S::

N 0

l -CV-TV-150A Cont vacuum pump B outside cont isolation valve Closed SI l -CV-TV- 150B Cont vacuum pump B outside cont isolation valve Closed SI one l-CV-TV- l50C Cont vacuum pump A outside cont isolation valve Closed SI l -CV-TV-150D Cont vacuum pump A outside cont jsolation valve Closed SI 1-CW- OV-I00A a Circ water condenser outlet isolation valve Closed CLS-HiHi

• one 1-CW- OV-100B a Circ water condenser outlet isolation valve Closed CLS-HiHi

• one I -CW- OV-IO0C a Circ water condenser outlet isolation valve . Closed CLS-HiHi

• one 1-CW-MOV-lO0D a Circ water condenser outlet isolation valve Closed CLS-HiHi

• one 1-CW- OV-106A a Circ water condenser inlet isolation valve Closed CLS-HiHi

• one a_ These circuits have features that could prevent immediate operation of the component when the engineered safeguards signal is actuated. Such features are a necessary part of the circuit (such as a limit switch), or they require conscious effort by an operator to prevent operation (such as manipulation of a pushbutton or a selector switch). A valve limit switch could act to delay safeguards- initiated operation if the valve was in mid-travel and had to complete the travel sequence before operating in response to the safeguards signal. A pushbutton or selector switch held in the actuated position gives the operators an option, in some cases, of delaying component response to an emergency safeguards signals.

b. A key-operated switch is under administrative control to prevent inadvertent component operation and to satisfy the requirements ofIEEE Standard 279-1971 . -....:i

c. A mode switch is under administrati e control to re ent inadvertent a(iQnment of this dam er duri V, I

N

d. The valve tag number listed is for Unit 2 because there is no equivalent valve tag number for Unit 1.

I I

INSERT

Table 15.2-1 (CO TINUED)

STRUCTURES, SYSTEMS, AND COMPO TS DESIO

• ED FOR SElSMIC AND TORNADO CRITERIA (Refer to the equipment classification list (Q-list) for a more comprehensive list of components. See ote 1.)

Earthquake Tornado 0 u,

Item Criterion Criterion Sponsor3 ote

c. Pressurizer surge line was reanalyzed per NRC Bulletin 88-11, dated December 20, 1988. C I

'-a 0.

Systems (continued) p)

Reactor coolant system (continued) [

Pressurizer safety and relief valves I p w Safety injection system n 0

Accumulators and supports I A w -....l w

Low-head safety injection pumps and piping l p w P for containment integrity

~

Boric acid injection tanks and piping I p w 0 Piping, valves, and supports I A SW Except drain/sample lines Containment spray system Refueling water storage tank I A SW Containment spray pumps I A SW

"'01 Piping, valves, and supports I A SW Except recirculation lines r:r.i C

Refueling water chemical addition tank SW Recirculation spray systems Recirculation spray pumps and piping p SW P for containment integrity Recirculation spray heat exchangers I A SW Reactor containment sump and screens I A SW Piping, valves, and supports I SW Vt ivI w

Revision 51.05- Updated Online 07/30/20 P UF AR 18-4

• Diesel-driven fire pump fuel oil storage tanks

• Refueling water storage tanks REPLACE

• Emergency condensate storage tanks

• Fire Protection/Domestic water storage tanks (re-inspection required during the Period of

~xtended Operation)

• Emergency serv ice water pump die el fuel oi l st rage tank An engineering eva luation may determine that the observed condition is accepta bl e or requires repair; or, in the case of degraded coatings, may direct removal of the coating, non-destructive examination of the sub strate material, and replacement of the coating.

Re-inspections are dependent upon the observe d surface cond ition , and the result

• of thi engineering evaluation. For the one-t ime inspections, tank conditions were confirmed to be acceptab le, but the tire protection/domestic water torage tanks require re-inspection during the Period of Extended Operation. Corrective actions for cond itions that are adverse to quality are performed in accordance with the orrective Acti n ystem. 01Tect ive action provides reasonable assurance that conditions adverse to quality are promptly corrected.

In addition to the one-time inspections of spec ifi ed tanks, a second aspect of Item 1O Table 18-1 is to eva luate the need for ongo ing inspections. The one-time in pection resu lts for all tank , except the fire pr tecti.on/domestic water storage tanks, indicated acceptability during the complete Period of

• xtended perati n (P ). The fire protection/domestic water storage tank will require re-inspection during the PEO based on an engineering evaluation of th~ one-time inspection results .

The combination of acceptable resu lts from the one-time inspecti n , and the development of plans for future inspection of the fire protection/domestic water storage tan I s, completes the task required fo r Item 10 Table 18- 1.

18.I.4 Non~Environmental Qualification (EQ) Cable Monitodng The purpose of the Non-EQ Cab le Monitoring activ ities is to petfi rm in pections on a limited, but representative, number or accessible cable jackets and connector coverings that are utilized in non- _, Q applications (I tem 19 Table 18-1 ). In order to confirm that ambient cond itions are not changing sufficiently to lead to age-related degradation of the in-scope cable jacl ets and connector coverings, initial visual inspections for the non-EQ application insulated p wer cables, in trumentation cables, and control cables (including low-voltage instrumentation and control cables that are ensitive to a reduction in insulation resistance) are performed in accordance with a stat ion procedure. Visual in spect ion of the representative samp les of non- Q power, instrumentation, and contro l cable jackets and connector coverings detect the pre ence of

Serial No. 21-138A Docket Nos. 50-280/281 Enclosure Attachment 2 PROPOSED SURRY UNITS 1 AND 2 UFSAR UPDATE {FINAL)

Virginia Electric and Power Company (Dominion Energy Virginia)

Surry Power Station Units 1 and 2

Note to As-Builder:

Revision 51.05- Updated Online 07/30/20 RED changes are associated with REMOVE SPS-UCR-2020-009 BLUE changes are associated with this UCR ubsystem .. . ... . ...... .. .. . . . . . . . .

it e REMOVE Figure 6. 1-1 Unit 1 Engineered afeguards Systems .......... . ............ .

Figure 6.1-2 Unit 2 ngineered afeguards ystem . .. , ... . . , ....... , , . ... .

F igure 6.2-'I Safety Injection System ............. . .......... ..... . ..... . 6.2-55 Figure 6.2-2 Protection Provided by Various mbinations of Safeguards Components ................................... . 6.2-56 Figure 6.2-3 Available NP H U-JSI Pump NP I Available Analysis .. .. . .. .. . 6.2-57 FiguJe 6.2-4 ontainment Pressure LHSI Pump NPSH Available Analysis ..... . 6.2-57 Figure 6.2-5 ontainment emperatures LHSJ Pump NP H Avai.lable Analy is .. 6.2-58 Total RSHX Heat Rate LHSI Pump NP H Available Ana lysis ..... 6.2-58 6.3-26 igure 6.3-2 nit I Recirculation Spray ubsystem . .. ....... . ... .. ..... . . . 6.3-27 Figure 6.3-3 Unit 2 Recirculation Spray ubsystem .. ..... ..... .... .... ... . 6.3-28 Figure 6.3-4 Piping and omponents levation pray ystems . .. ........... . 6.3-29 l* igure 6.3-5 Typical - eneral Structural and Piping Arrangement Recirculation pray and ow Head afety Injection Systems Outside the Reactor Containment ............. . 6.3-30 F*igure 6.3-6 Out ide RS Pump NP HA vailable Analysi DEHLG at l 0.3 psia, 25°F W .................. . ... ....... . 6.3-31 Figure 6.3- 7 Ouhde R Pump NP HA vailable Analysis DEHLG at 10.3 psia, 25°F SW .... .. .. ... .. ........ ........ . 6.3-3 1 Figure 6.3-8 Outside R Pump NP H Available Analysis DEHLG at 10.3 psi a, 25°F W .. ......... .................. . 6.3-32 Figure 6.3-9 Outside R Pump NPSH Available Analysis D HLG at 10.3 psia, 25° W ............................. . 6.3-32 Figure 6.3-10 inside R Pump NP Available Analysis DEPS at 10.1 psia, 70°F W ......... . ..... .. .. .. . .. ...... . 6.3-33 Figure 6.3-11 Inside R Pump NP H Available Analysis D P at 10. l psia, 70° W .............................. . 6.3-33 Figure 6.3-12 Inside R Pump NP H Available Analysis DEP at 10.1 psia, 70° W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3-34 Figure 6.3-13 In ide R pump NPSH Available Analysis DEPSG at 10.1 sia 70°

• W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3-34 Figure 6.3-J b Unit 2 ontai system . . . . . . . . . . . . . . . . . . . . . . . . . 6.3-26b REMOVE

Revision 51 .05- Updated Online 07/30/20 P UF AR 6.1 -1 CHAPTER6 ENGINEEREDSAFEGUARDS 6.1 GENERAL DESCRIPTION Note: A required by the Renewed Operating Licenses for urry Units 1 and 2, issued March 20, 2003, various systems, structures, and components discussed within this chapter are subject to aging management. The programs and activities necessary to manage the aging of these systems, structures, and components are discussed in Chapter 18 .

The engineered afeguards, t gether with the containment ( hapter 5), protect the public and the station in the event of the design-basis accident, as defined in Sections 14.5 . 1.2 and 14.5.5. The engineered safeguards are designed to minimize the accident by performing the fo llowing three functions:

I. Supply borated water to the reactor coolant system to cool the core, decrease reactivity, limit fuel rod cladding temperatures, limit the metal-water reaction, and ensure that the core remains intact.

2. Limit the driving potential, including differential pressure and time duration, for leakage out of the containment trncture.

3. Reduce the concentration of airborne fission products available for leakage.

The first function i satisfied by the timely, c nlinuous, and adequate supply of borated water to the reactor coolant system and the reactor core. The second function is satisfied by the provision of heat sin I s for the condensation of steam released inside the containment, the inherent depressurization of the containment below atmospheric pre sure following the design-basis accident, and means for maintaining the containment at subatmo pheric conditions for an L------...::---' extended eriod of time. The third function is atisfied b rovidin chemical additiv (NaOH)

1. A safety inj ection system (

reactor coo lant loops.

2. wo separate low-head safety injection subsystems, either of which provides long-term removal of decay heat from the reactor core.

3. Two eparate ubsystems of the spray system (containment spray and recirculation spray) that operate together to reduce the containment temperature, return the containment pre ure to subatmospheric, and remove heat from the contairunent. The recirculati n spray subsystem maintains the containment subatm pheric and tran fers heat from the containment to the service water system ( ection 9.9).

Revision 51 .05- Updated Online 07/30/20 P UP AR 6.J-2 A compo ite chematic diagrnrn of the engineered safeguards systems is shown in Figu re 6.1- 1 and 6. 1-2 for Units 1 and 2, respectively.

The safety inj ction ystem. provides for the charging of borated water to the reactor coolant sy tern from the accumu lators following a LO A. The three accumulators are self-contained and arc de igncd to supply water as oon a the reactor coolant system pressure drops below 600 psig.

Additional makeup to the reactor coolant system i prov ided by the charging pumps, operating in the safety injection mode, and the low-head afety injecti n pumps. Both the charging and low-head safety injection pump

• are I cated utside the containment, are driven by an electric mot r, are capable of b ing rapidly energized or op rated, and are powered from the emergency power buses. The pumps also ensure an adequate supply of borated water for an extended peri d of time by recirculating water from the containment sump to the react r cor through two separnte flow paths.

The containment spray subsystem supplies ch illed borated water to the containment immediately following the receipt of the safeguards initi ation signal. Th is ubsystem includes two full-capacity, elcctric-m tor-driven containm nt pray pump that are located outside the containment and are . uppl ied with power from the emergency buses. The containment spray pump upply chilled water from the refueling water storage tank to the containment. ither pump is capable of furnishing sufficient spray water to prevent verpr surizing the containment structure A chemical ad iti n tank I a lanced hydraulica ly wit the re ue ing water storage tank an cl provides a flow of sodium hydroxide solution to increase the aUcalinity oft e co a* ------

INSERT t f lo

• d' a i e i The recirculation pray subsystem recirculates water from the containment sumps 1rough REMOVE service-water-cooled recirculation spray heat exchanger to the r circulation pray h aders. Tw of the four 50% design capacity motor-driven rec irculation pray pumps are located outside the containment. All four of the recirculation spray coo lers are located inside the containment and transfer conta inment heat t the ervice water system ( ection 9.9).

The conta inment spray and recircu.lati n spray subsyste s are capable of reducing the containment pres ure to subatmospheric in less than 60 minute thus terminating all outleakage t the environment. This original design criterion was modifie in conjunction with th analy es for implementation of the alternative source term. Tbe modi 1ed crit ria require that, fol lowing the LO A, the containment pressure be less than 1.0 psig ithin 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and less than 0.0 psig within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. The radiological consequence analysis der onstrates acceptab le results provided the containment pressure does not exceed 1.0 psig for the

• terval from I to 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> fo llowing the Design Basis Accident. Beyond 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> containment pre sure is as umed to be Jes than 0.0 psig, terminating leakage from containment.

REMOVE INSERT The containment vacuum syst m rem v s ny subsequent ai r inl eakage fter the containment pressure has been reduced to subatmos heric. Because of the inherent low eakage design of the conta inment, the use of the vacuum p mps will probably not be required for veral dium Tetraborate Decahydratc (NaTB) is stored in ba ket in id containment to increase the alkalini ump water produced during an event which exceeds the L high-high containment pressure actuation whi ch is rccircul at d by the r circul ati n pray sub ystem to ensure effective remova l of radi oactive iodine_,_.,.._..,,.._,,

REPLACE WITH INSERT A Figure 6.1-2  ;::o 0

EEREDSAFEG en 0

I V,

0 V,

b "O

CL

~

Ct>

0..

0

-s*

s C'll Alt Unll

!l'I\IST -0

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0

~

0

~

I

~rl~'--~--~~

,~ ,_,,__,_,

• -- - -- ~

T--'

I ---.____,

, _ _ _ _~ ,

Legen<l:

RCS* ReaCIDr Coolaru system l'!Jrs f r o m ~ S>,np ToWwo i't1 I* Co-Wo;,;,adMd- 11'1 Too FootlN<k-Concra>I

~Mot Note:

RM;T lnstNmenla'Son shatmon!lli>~

V.OS

• V.'os:e OiSP=Ol ~

V.t.C

• Weight cad Che<:lt lhlYe ~ ralher lhan -

Gr.iptur;a: No.esm5 0, I

v-,

IINSERT A I

~ 11:f.' ,

~l

~I-' ~~::=:;;;;==:ttifu~

~l

---+--~--~+- ....., ""

RV-ST

-LOcer YOS ate.:

RVIIST lnstramenta6on

.snawn en d'lis dnr..ing is typical ra er "1an aciUal.

Gnp 'cs No. CSSU.S

Revision 51 .OS- Updated Online 07/30/20 P UF AR 6.2-l5 The following information is HJ. TORl 'AL and is not intended or expected to be updated for the Life of the plant.

1. Two production line motors were used for this test. One was expo ed to a total of 1.5 x 10 8 rad of gamma radiation in approximate ly one month. he other motor was used for the final comparative analy is.

2. Both motors were te tcd for coil re istanc by the Wheatstone bridge method, and for inslilation resistanc by meggering both before and after motor vibration and reversing perations.

The co * ** *

• with a postaccident solution of boric ac*

REPLACE -----

nd 6.2.2.2.5 Th sta inl ess tee manua go e, gate an c cc<. v 111 accordance with the requirements outlined in the m to r-o pernt

( clion 6.2.2.2.4).

The carbon steel valve are built t conform with U A B 16.5. The materials of construction of the body, bonnet, and disk conform to the requirements of A TM A I05, rade 11; A 181, rade Tl; or A2 I 6, rade WCB or W . The carbon steel valve pass only non-radi active gases and were subjected to hydro tatic te ta outlin d in M - P-61, except that the te t pressure was maintained for at least 30 minutes.

6.2.2.2.6 V nt Valves High point vents have been in talled at critical points in the suction lines of the charging (HH I) pumps, and the discharge lines of the LH I pumps where gasses cou ld collect.

6.2.2.2.7 Accumulator heel Valves The pre ure-containing parts of these valve assemblies are de igned in ace rdance with M P-66. Parts in contact with the operating fluid are of austenitic stain less steel or of equ iv alent corrosion-resistant materials procured to applicable A TM or Westinghouse specifications.

Revision 51.05- Updated nline 07/30/20 PS UF AR 6.2-24 The th ree combinations (Bars A, B, and ) represent degraded cases with operation of les than the installed emergency core cooling equipment. The e cases are shown only to present the capabi lity of individual portions of the system and to demonstrate the overa ll margins of the system. The operation of one safety injection charging pump together with two accumulators is probably capab le of provid ing protection over a considerably greater range than shown. However, the analys is has on ly considered breaks up to the 8-inch diameter.

Bar D, which is th comb ination of the safety equipment in Bars B and , and which also repr ents the minimum engineered safeguards available automatically, provides protection as shown over the complete range of break sizes up to and including the comp lete circumferential fracture of a reactor coolant pipe.

For the small range of break sizes up to 2 inches, a shown in Bar A the action of one safety injection charging pump acting alone i sufficient to mainta in enough core water inventory to ensure continued core cooling.

6.2.3 .2 Borated Water Injection Chemistry During the injection of emel'gency coo ling water into the reactor coo lant system fol low ing a LO A, the concentration of bornn wi ll vary depending on the depressurization hi story of the reactor. Tf depressurization were slow, the high-head pump would inject boric acid at a concentration greater than 2300 ppm, which would be diluted by the coolant remaining in the system. Rapid depl' surization would bring about early injection of water containing boric acid at a concentrati on greater than 2250 ppm from the accumulators. When recirculation begin , the average concentration of boric acid is (and wi.11 remain) at a concentration that will maintain the core suberitical.

The concentrations of other materials, including chlorides, are quite low in this so lution, corros ion products being generally insoluble in a basic so luti n. Assuming 50% of the maximum core inventory i released t c ntainment after a LO A, the principal fission product in the sump (assuming a gro score fa ilure) would be iodine at a range between approximately 1.6 to I. ppm for 500 day of operation and approximately 3.0 to 3.6 ppm for 1000 days fop ration. The ....-------.

temperature of the sump water is reduced below I 50°F, und r n rmal perating conditions with a REMOVE minimum of two recirculation cooler in operation, after a relatively short period of time few hour ). Bel w J 50°F, ch lorid t *e l

......~--- ....

6.2.3.3 Chemical Additives ontainment tra

• w that .

having a pH between ..__~,____,....,,..,,,,, ill be u or approximate y 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> if minimum safeguards operate an approx1ma ly 50 minutes if normal safeguards operate. During this period, the containment wi II be cooling from 280°F to approximately l 40°F. At the end of the initial c ntainment cooling period, lasting no longer than approx imate ly one hour, the recirculation spray system will continue in service for an indefinite period* however, the pH of the

INSERT box and italicized text INSERT-~

recircu l further addition of chemical

• es is not contemplated.

The following information is only applicable to Unit 2.

Jn crt B odium hydroxide i l1 nnally stored for many industrial applications in atm spheric-vented tanks. Reaction of sodium hydroxide with atmospheric carbon dioxide to form a large precipitate docs not occur. However, to eliminate particulate matter from any potential source, the containment spray subsystem include, a strainer on the suction side of the containment spray pumps . This strainer will have openings smaller than the smallest spray nozzles, and therefore will remove any particulate matter from the containment spray flow that might prevent the system from functioning.

T illu trate the remoteness of a CO 2 + Na H reaction, calculations were made based n the foll wing as umptions:

I. The tank temperature varies from 35° to 95°F each day, cau ing the tan! t breathe.

2. Al l CO 2 entering the tank react with the cau tic.

The al cu lations indicate that this process must continue for 90 years to react with I% of the stored caustic. This reaction would not cause a precipitate to :B rm .

Ba ed on past operating experience and calculational re ults, as dium carbonat prec1p1tat cannot form; therefore , the functioning of the system will not be impaired because of precipitation.

The major construction materials that will be exposed to the containment spray

_____.__ _, and the corms.ion or deterioration rates for each under maximum exposure conditions, are

._____ Table 6.2-7. - - - -.....

REPLACE containment tcrials adversely a pray are aluminum and zinc.

\...J...>.. . A..Jo..J...>...>..A..)......_,-..,..Y"v'h-v e"'Yt--c im~er--,....te..--m~ erature expo ure conditi n under which the e material will be exposed to hemical additiv spray are from approximately 50 minute to 11/2 hours, with the temperature 0 to 140° .

The materials will also be expo ed t the recirculation sprays, which have a pH between 7.0 and 9.0 fir the po taccident recirculation period with the temperature at approximately 140°F.

The consequence f corro ion and/or deterioration on materials with regard to postaccident operation of the engineered safeguards is negligible because components of the engineered safeguards are constructed of stainless steel. REMOVE The corr ion rate of stainless steel is low enough in the concern (Reference I).

REMOVE box and italicized text only Insert B The.following information is only applicable to Unit J odium Tctrab rale Decahydrate stored inside containment is a white crystall ine chemical in granu lar form. The NaTB i stored inside baskets which contain the chemical until it is dissolved by the containment sump water. To eliminate particulate matter from any potential ource the containm nt pray sub yst m include a train r on the . uction side of the containment spray pumps. This strainer will have openings smaller than the smallest spray nozzles, and therefore wi ll remove any particu late matter from the containment spray flow that might prevent the ystcm from functioning. Add itionally, using NaTB a a buffer doe not re ult in any different pr cip itates than those that form with the original NaOH buffer and the amount of precipitates is reduced, resulting in lower trainer head losses. Therefore, the functioning of the system will not b impaired because of precipitation.

Revision 5 1.05- Updated Online 07/30/20 P VF AR 6.3-l 6.3 CONSEQUEN E-LIMITING SAFEGUARDS 6.3.1 Spray System 6.3.1.1 Design Bases The spray system con ists of the containment spray subsystem and the recirculation spray subsystem, which are designed to pr vide the necessary cooling and depressurization of the containment after any LOCA. pray system component data are given in Table 6.3-1 .

Safety related comp nents, piping, valves, and supports in the spray system are eismic ategory I.

The subsystem , perating together, coo l and deprcssurize the containment to subatmospheric pressure fo llowing the design-basis accident.

The recirculation subsystem is, in addition, capable of maintaining the subatm pheric pressure in the containment for an extended period fo llowing th design-basis accident.

REMOVE INSERT The removal of radioactive iodine from the containment atmos here after a design-basis ent INSERT epressurize the containment t subatmospheric pressure 1 1 any one of the two containment pra . , . .

spray pump operating. dissol.ution of odium tetraborate decahydratc int the containment REMOVE sum water which i u ed by the recirculation spray subsystem

- - - -- 6.3.1.2 pray ystem Components

( nit I an th The spray system is designed, fa l of the Genera l Design riteria, as 1scusse ubsy terns and their components are considered to be essential to accident prevent1_ n and/or the mitigation of accident consequences that could affect the public health and safety.

6.3.1.2.1 Pumps and Valves The spray pumps and valves are fabricated, welded , and inspected according to the requirements of the applicable porti n f the A ME Code, ections llI, Ylll and IX. Materials of construction are sta inl es stee l or equivalent corrosion-resistant mat rials.

Valve packing and pump eals are selected to minimize or elimin ate leakage where necessary. Motor-operated valve operators are se lected because their proven superior reliability in past appl ications ensures r liable valve operation under incident conditions.

The Teflon sl ve and pacl ing of the outside recirculation spray system suction valves have been changed to XOMOX 7. This changer fleets the review performed in accordance with N UR G-0578, Section 2.1.6 .. In thi review it was found that the valves would be located in a

Revision 5 1.05- Updated Online 07/30/20 P UF AR 6.3-2 high-rad iation area as a res ult of a L A. The efl n material is satisfactory to only I x 104 rads, wher as th XOMOX 7 materia l L satisfactory to 8 x 10 6 rads. The expected 60-year normal plus postaccident integrated radiation dose in this area is conservatively estimated not to exceed 8 x 106 rads.

REPLACE T he conta inm ent spray system piping and equipment are fabricated of A TM A358, Type 304 sta inless steel, or equivalent, which has a corrosion rate of less than 0.0001 in/yr at the rv-vvv-v-v--A'~am-~~~!~~t:~~~~~>!~~.l;_~~~~~ia,......-e.,...,,lH......~~ an 8. 7 to 10 .4 H.

4.25 to 4 pment are also fabricate ype 304 or Type 316L stainless steel, or equ ivalent, exce t for the Recirculation pr* xchanger (R HX tubi * * * ** anium and th ,,......,.....,....,.,,.....,..;-v,,....,_ h are bra operating 1s inhibite ypothetica l env iron ment after the design-basis

~ -- - -- -~REPLACE pe a e at a relatively low pressure of approximately 100 psi gauge and are not highly stressed during operation, so that the inducement toward cracking is reduced.

eca u e t e p J of the containment pray solu tion is a ove . an the recirculation spray so lu tion pH is essentially 8.0, the potential for caustic stress corrosi n crack in g in the containments ra s stem and recircul ation s ra system is virtual! nonexjstent.

I for caustic tress corrosion cracking in the containment

• ray ystem and spray sy tern is virtually nonexistent because * ,....,-..,...,,..,,..... 1g:

I p taccident REPLACE The containment motors have been selected to ensure operation during O A conditions.

Motor electrical insulation is in accordance with AN l, I E, and N MA standards. he motors REPLACE re tested as required by these standards. Bearings are antifric tion type. Bearing loading and

.....__ _ _ _ 1igh-temperature test have been performed, and the expected bearing life equals, or exceeds, that spec ified by the Anti *riction Bearing Manufacturers Association (AFBMA).

6.3. l .2.3 Pi pin g P ipin g fabrication, installation, and testing are in accordance with the pecification for Power Plant Piping, AN I B3 I. l, with supplementa l requirements and inspections as necessary

R vision 51.05- Updated Online 07/30/20 P U* AR 6.3-4 The suction Lines between the containment sump and the ORS pumps are cross connected.

Thi s design feature was orig inally provided to ensure a supply of water to each pump in the event that the suction of either pump become clogged. The current common header stra iners that pr tect the pump suction lines are designed to with tand the full debris load that could be generated by a LOCA.

The design data of the spray system components are given in Table 6.3- 1.

6.3. 1.3 Description 6.3.1.3.1 ontainment pray System The containment spray y tern cons ists of two completely sepa rate trains of spray rings located in th c nta inment dome and one common spray ring located out ide the crane wall. ach train i rated at l 00% capacity. The recirculation spray system is compo ed f two trains each cons isting of an inside reci rcula tion spray subsystem and an outside recirculation spray subsystem. ach sub y tern is approximately 50% capacity, and consists of one recirculation spray pump, one recirculation spray heat exchanger (R HX), and one 180° coverage spray header with nozzles. -----

RE PLACE An additiona l ring header common to both containment spray trains is insta lled at Elevation 95 ft. 6 in. outs ide the crane wall. Check valves are installed in each branch connection from the ri ser to the common header to limit fill time, shou ld on~~~~.-+><~~~~,>tr~&J,v~...,...,'""'"'.,...,..vv~~

start. Figur 6.3-1 a (Unit 1) and Figure 6.3- 1b (Unit 2)

The conta inm en t spray su re 6. nd the recirculation spray subsystem is shown in i ,,....,...,...,....,........,..,,....,...""" al piping and nent of these subsystems

.-----_,arc shown in Figure 6. ~--.A.,;-"-1~'-"'-"" IN SERT 1,....----\.,

• nl ,..R_E_M_O_V

_E_,,

REMOVE -

Eac s water in water to1 . sed for iod ment atm to the con

• the chemica l ad refueling w m and a dom top, and is secured to a reinforced-conc rete foundat ion. The refueli1 torage tank is fabricated of A TM A240, Type 3041 sta inl e s steel, in accordance TD-650. The requirements for welding, welding procedures, welder qualification, wel point efficiency, and weld inspection are in accordance with Section IX of the A M , ode the )ecification for Fie ld Fabricated torage Tanks Reference 4 The chemical add ition tank is a vertical cy lindrical vessel with f ange and di hed heads mountecl on a kirt and secured to the reinforced concrete foundati n. The chem ica l add ition tank is fabricated of A TM A240, Type 304 tainless teel in acco rdance *

• Both tanks are designed as Class I component , as described in ection 2.5 , to withstand REPLACE design se1sm1c ss criteri a of A M ode ection III, Figure N-414, uc .ear esse s. e connectmg p1p11 signed to withstand seismic load*

he refueling water storage tank is designed a a la I component

Revi i n 51.05- Updated nline 07/30/20 PS UFSAR 6.3-5 ensure th functioning of the system. The refueling water storage tank is pr vided with a manhole for inspection access.

Prior to unit operation, the water in the refueling water storage tank is cooled to a temperature of slightly below 45°F by either circulating the water through a heat exchanger that uses chilled water from the chil led wat r subsystem f the c mponent cooling system

( cction 9.4) or by u ing mechanical refrigeration units. Mechanical refrigeration units then maintain the tank water below 45°F. The tan l is insu lated. The refueling water storage tank also has a nozzle connection that supplies water to the safety injection system ( cction 6.2).

The refu ling water storage tank (RW ) is a passive component and is required on ly during a short period fo llowing an accident. It is provided with four channels f level indication, which provide signals to level indicat r, . The level ind ication range for the RWST is approximately J 4,000 gall ns at 0% leve l to approximately 399,000 gallons at 100% level. The RW Ti maintained at greater than 387, l 00 ga llons of borated water at or below a temperature of 45°F during normal plant power operations. Level transmitters provide input to a low level alarm and an empty alarm when RW T level drops below these respective setpoint . When tw of ti ur channels have sensed a low RWST level condition, an interlock ignal i generated to allow for the start of the IR and OR pumps on a L I-E-Hi Actuation. Additional ly, when two of four channe ls have s nsed a low-low R W level condition, a signal is generated to realign afety injection to the recirculation mode automatically. It takes approximately three minute to r align the va lves from injection to recircu lation mode. The key value fo r th RW T assumed in the safety analysis are presented in Table 5.4- 17. The safet anal sis values are conservative with respect to plant operation.

The chemical addition tank 1s r storage tan . e normal operating capacity of the AT, including in trument uncertainties, is greater than the minimum AT vo lume of 3800 gallons assumed in the afcty analy is. Flow f the sodium hydrox ide solution is from the chemical addition tank directly to the containment pray pump suction via a caustic add ition line. This flow path pr vides for a reduced caustic trans it time and introduces the caustic at an es ntially on tant rate. The con tant add ition rate Rrovides for a more constant pray pH during the variou modes of afeguards system operatio INSERT A line fr m the chemica l addition tank circu lating pump is installed to permit periodic circulation of caustic solution in the pip ing and maintain the capability of recircu lating th chem ical addition tank.

IN SERT The chemica l addition tank 1s msu a e an t e recirculation line is electrically heat traced to keep the tank and recirculation line c ntent at a temperature well above the freezing point of the chemical spray elution. The chem ical add ition tank has a low-temperature alarm set at 35°F.

The containment spray pumps are capable of upplying approximately 3200 gpm of borated water to two eparate circular containment spray ring headers located approximately 96 feet above the operating floor in the dome of the containment structure and the common crane wall

Revision 51.05- Update The recircu lation sp,_,......,,_.,".....,,_..,._.,,__,~.._,,_,._..,.__.. .,,_,.,_.,_<<-...._..ection or smoke or air test folJowing maintenance or an activity which cou ld cause bl ckage to provide indication that plugging of the nozzles has not occurred . The test ing of sys tem contro ls is discussed in ection 7.5.

Electrical insulation resistance tests are performed during the lifetime f the R motors to verify the integrity of the insulation. Periodic tests are also performed to ensure the motors remain in a relia le perating condilion .

The Recirculation pray ystem is subject to the applicable in servic inspection and inserv ice testi ng requirement f the A ME ode, as required by 10 FR 50 (Code of Federal Regulation , Title 10, Part 50).

6.3 REFERENCES

l. NR Bulletin No. 93-02: Deb,.;s Plugging of Emergency Core Coo ling Suction Strainers, dated May 11, 1993 .

2. Letter from Virginia ~ lectric and Power ompany to the NR , dated June I0, 1993, erial No.93-307, Response to NR Bulletin 93-02.

3. Letter from Virginia Electric and Power Company to USNRC dated February 7, 1996 ( erial No. 95-566A), Generic Letter 95-07 Pressure Locking and Thermal B;nding of Safety-Related Power-Operated ate Valves, urry and North Anna Power StaUon.

4. tone & Webster pecification NU -25 8 Specijlcation for Field Fabricated Storage Tanks, Rev ision 2.

5. NR Generic etter L 2004-02, PotenUal Impact of Debr;s Blockage on Emergency Recirculathm During Design Bas;s Acddents al Pressurized Water Reactors , dated eptember 13, 2004.

6. Nuclear Energy Institute (N 1) Document N *J 04-07, Pressurfaed Water Reactor ump Pe,formance Evaluation Methodology, dated December 2004.

7. afety Evaluation by the Office of Nuclear Reactor Regulation Re lated to NR eneric Letter 2004-02, Nuclear Energy In *titule uidance Report Pressw*;zed Water Reactor ump Pe,formance Evaluation Methodology.

8. Letter from Dominion Resources Inc. to the NRC dated

• eptember 1, 2005 , eriaJ No. 05-21 2, Response to NRC Gener;c Letter 2004-02.

9. Westinghouse Document WCAP- 16406-P, Revision 1, Downstream Wear Evaluation Methodology for Containment Sump Screens in Pressurized Water Reactors.

10. Westinghouse Document W AP-16793 -N P, Revi sion 0, Evaluation of Long-Term Cooling onsidering Particulate, ibrous and Chemical Debris in the Recirculating Fluid.

ADD Insert C

In ert C

- - - - - l l . U. . Nuclear Regulatory omm 1ss1on tandarcl Revi ew Plan NUREG-0800, hapter 6 ection 6.1.1 Rev 2, Engineered Saf ety Features Materials.

WCAP-7153, lnvestigat;on of 'hemical Additives f or Reactor 1968.

WCAP-16596-NP, Revi sion 0, Evaluation ofAltem ath e Emergency 1

Agents, dated Ju ly 2006.

Revision 51.05- Updated nline 07/30/20 SP UFSAR 6.3-2 .1 Table 6.3-1 (CONTINU D)

DATA Number REPLACE ype Vertica l cylindrical Capacity INSERT 4311 ga l Design pressure 25 psig Design temperature 150°F Material ss 304 Design code ASME ection Ylll REMOVE Operating pressure Atm spheric Operating temperature Ambient Na H concentration 17-18%

hemical Addition Tank Pump,__,,.__..-Jo~~-

Number REPLACE Type Rated fl w 50 gpm Rated head INSERT 7 ft Theoretical horsepower 0.1 hp Seal Mechan ical Design pres ure 225 ps ig Materia l Pump cas ing Shaft trainer Assembly 1 (for both OR and IR ystems)

Material 304 Design ode A ME Section III, Subsection NF, Class 3 trnctura l DP 9.0 psid Perforations 0.0625 in. diameter Operating Pressure 9.0-59.7 p ia Operating Temperature 75 -280° Fluid Flowing Borated water Piping ADD Piping is designed to the ode fo r Pressure Piping, AN I 31. 1.

Insert D Valves Recirculation Spray system valves are designed in accordance with AN I B 16.5, tee I Piping Flanges and Flanged Fittings, or AN J B 16.34, tee! Butt-Welded End Va l.ves.

Insert D REMOVE odium Tetraborate Decahydrate Baskets ......._.,._,.,,_..,.__.....,,

Number Material REPLACE Basket 304 Wheels Duplex 2205 Nominal size (internal dimen ion ) 6 ft X 5 ft X 1.5 ft Operating Pres ure 9.0-59.7 psia Operating Temperature 75-280°F Technical pecificat ion minimum 10760 lbm INSERT hem ical Grade SQ Granular hemical pecification B2 3 36.5-38.3%

Equivalent Na2B~Or 10H2O 99.9-105.0%

Na2O 16.2- 17.1%

04 S 3.0 ppm I  :::: 0.4 ppm Fe S 2.0 ppm hemical ieve pecification tandard No. 8 Retained  ::: 0.1%

REPLACE REPLACE INSERT REPLACE WITH INSERT E REMOVE co BSYSTEM INSIDE REACTOR OUTSIDE REACTOR CONTAINMENT CONTAIN ENT REFUELING WATER STORAGE TANK 0 V,

I I

2-360° SPRA\'HEAOBIS CtlEIAlCAL ADDITION TANK

!  :::i

i I 0

-~

0

-.....)

I 2* RECIRCULATION v .l I

0 PUMPS l

I 2

• I.IEOHAJIICAL REFRIGERATION I UNITS FOR TEMPERATUR'E

(/J

"'d

(/J I ~

(/J I

AC

0 l

WLC -WEIGHT LOADED CHECK VAi.VE

• TO CHECKOPERATIOtl' OFWLC RWST INSTRUMEITTATIO SHOWN ON THIS BLEED FLOW DRAWING IS TYPICAL RATHERTHAH ACTW<L DRAIN 0

0 C')

0

<D 0

rn BLEED A.OW DRAIN

ADD NEW FIGURE 6.3-1b IREMOVE FIGURE AND PAGE ~ ON NEW PAGE AFTER FIGURE 6.3-1 a Figure 6.3- lb UNIT 2 CO TAlNME T SPRAY SUBSYSTEM INSIDE REACTOR OUTSIDE REACTOR CONTAJNM ENT CONTAINMENT REFUEi. G WATER STORAGE TANK 2- 360 ° SPRAY HEADERS CHEMI CAi..

ADDITIO TANK 2-RECIRCULATION PUl,IPS 2

• MECHANICAL REFRIGERATION UNITS FOR en TElolPERATIJRE "'O en NOTES:

Wl.C - WEJGHT LOADED CHECXVALVE

• TO CHECKOPERATIONOFWLC R\VST I NSTRUMENTATION SHOWH O THIS BLEED FLOW DRAW G ISTVPICAI.. RATHER THAN ACTUAL.

DRAIII CONTAINMENT SPRAY PUMPS 0

0 0

<O WLC 0

(/)

Bl.EEO FL OW 0\

DRAIN wI N

0\

0-

Table 7.5-2 (CO TINUED) ~

VALVES/DAMPERS ACTUATED BY ENGINEERED SAFEGUARDS SIG ALS Vl 0

Function Override/Bypass  ::;

Designation (Valve or 2-CS-MOV-202Act 2-CS-MOV-2028d REPLACE (Actuated Valve or Signal (Override or bypass condition V,

0 V,

Damper Tag Io.) Service Damper (Actuation following C

I (Similar for nit 2) (Actua d Valve or Damper Description) Position) Signal) actuation) -0 C.

Con pray pump A discharge isolation valve Open CLS-HiHi one ~

C.

C t spray pump A discharge isolation valve Open CLS-HiHi one 0

um B discharge isolation valve CLS-HiHi one

s CLS-HiHi one 0 0

-....)

Open CLS-HiHi one w em add tank isolation valve Open CLS-HiHi one i5 0

1-CV-TV-150A Cont vacuum pump B outside cont isolation valve Closed Sl one l -CV-TV-150B Cont vacuum pump B outside cont isolation valve Closed SI one l -CV-TV-150C Cont vacuum pump A outside cont isolation valve Closed SI one 1-CV-TV-150D Cont vacuum pump A outside cont isolation valve Closed SJ one 1-CW-MOV-l00A a Circ water condenser outlet isolation valve Closed CLS-HiHi

• one Cl) 1-CW-MOV-l00B a Circ water condenser outlet isolation valve Closed CLS-HiHi

• one ""O Cl) 1-C -MOV-l00C a Circ water condenser outlet isolation valve Closed CLS-HiHi

• one C "Tl l-CW-MOV-100D a Circ water condenser outlet isolation valve Closed CLS-HiHi

• one Cl) l -C\.V-MOV-106A a Circ water condenser inlet isolation alve Closed CLS-HiHi

• one

~

a. These circuits have features that could prevent immediate operation of the component when the engineered safeguards signal is actuated. Such features are a necessary part of the circuit (such as a limit switch), or they req_uire conscious effort by an operator to prevent operation (such as manipulation of a pushbutton or a selector switch). A valve limit switch could act to delay safeguards-initiated operation if the valve was in mid-travel and had to complete the travel sequence before operating in response to the safeguards signal. A pushbutton or selector switch held in the actuated position gives the operators an option, in some cases, of delaying component response to an emergency safeguards signals.

b. A key-operated switch is under administrative control to prevent inadvertent component operation and to satisfy the requirements of IEEE Standard 279- 1971.

---.l

c. A mode switch is under administrative control to revent inadvertent aliQllment of this dam er duri U'l I

tv d . The valve tag number listed is for Unit 2 because there is no equivalent valve tag number for Unit 1.

IN SERT REMOVE

Table 15.2-1 (CO ED)

STRUCTURES SYSTEMS, ND COMPO DESIO D FOR SEISMIC AND TORNADO CRITERIA (Refer to the equipment classification list (Q-list) for a more comprehensive 1ist of components. See ote 1.)

Earthquake Tornado Item Criterion Criterion Sponsor-'1 ote

c. Pressurizer surge line was reanalyzed per C Bulletin 88-11 , dated December 20, 1988.

Systems (continued)

Reactor coolant system (continued)

Pressurizer safety and relief valves I p w

J Safety injection system Cl) 0 Accumulators and supports I IA w ---l w

Low-head safety injection pumps and piping I p w P for containment integrity 0

~

Boric acid injection tanks and piping I p w 0 Piping, val es, and supports I A SW Except drain/sample lines Containment spray system Refueling water storage tank I  ; A SW Containment spray pumps I A Except recirculation lines dditio Recirculation spray systems Recirculation spray pumps and piping SW P for containment integrity Recirculation spray heat exchangers I 'A SW Reactor containment sump and screens I TA SW Piping, valves, and supports I A SW REMOVE VI N

I v.)

Revision 51.05- Updated Online 07/3 0/20 PS UFSAR

• Diesel-driven fire pump fuel oil torage tan ks

• Refueling water storage tanks 2 nly) REPLACE

• REMOVE

• Fire Protection/Domestic water storage tanks (re-inspection req uLred during the Period of Extended Operation)

• Emergency serv ice water pump diesel fue l oil storage tank An engin eering evaluation may determ ine that the observed cond ition is acceptable or req uires repa ir; or, in the case of degraded coatings, may direct removal of the coating, non-destructive exam ination of the sL1b strate material and replacement of the coating.

Re-inspections are dependent upon the observed urface conditi n, and the resu lts of this engineering eva luati on. For the one-tim e inspecti n , tank co nditi ons were confirmed to b acceptable, but the fire protection/domestic water storage tanks require re- inspection during the Period of Extended Operation. orrective actions for conditions that are adverse to quality are performed in accordance with the orrective Action System. orrective action provides reasonable assurance that condition adverse to quality are pr rnptly corrected.

In addition to the one-time inspections of spec ified tanks, a second aspect of Item 10, Tabl 18-1 is to evaluate the need for ongo ing inspections. The one-time inspection resu lt fol: all tank , except the fire protection/domestic water storage tanks, indicated acceptability during the complete Period of xtended Operation (PEO). The fire protection/domestic water storage tank will require re-inspection during the P O based on an engineerin g eva luation of the on -time inspection results .

The comb ination of acceptable resu lts from the one-time inspections, and the development of plans fo r future inspection of the fire pr tection/dome tic water torage tank , comp letes the tasks req uired for Item l O Table 18- 1.

18.1.4 Non-Environmenta l Qualification (EQ) able Monitoring The purpose of the Non-EQ Cable Monitoring activities is to perform inspectio ns on a limited, but representative, number or access ibl cab! jacl ets and connector covel'i ngs that are utilized in non- Q applicati n (Item 19, Tab le I 8- 1). ln order to confirm that ambient conditions are not changing suffic iently to lead to age-related degradation of the in-scope cable jackets and connector coverings, initial visual inspectio ns for the non- Q application in ulated power cables, instrumentation cab les, and control cables (including low-vo ltage in strumentation and control cable that are sen itive to a reduction in insulation res istance) are performed in accordance with a station proc ed ure. Vi sua l in spectio n of th e rep resentative sa mpl es of non- Q power, instrumentation, and control cable jackets and connector cover ing detect the presence of