ML18190A162

Korea Hydro & Nuclear Power Co, Ltd., Revised Response to RAI 420-8482 for Question 19.03-36 (Rev.2)

ML18190A162
Person / Time
Site:	05200046
Issue date:	07/09/2018
From:	Korea Hydro & Nuclear Power Co, Ltd
To:	Document Control Desk, Office of New Reactors
Shared Package
ML18190A160	List: ML18190A161 ML18190A162
References
MKD/NW-18-0101L
Download: ML18190A162 (16)

Text

19.03-36_Rev. 2 - 1 / 3 KEPCO/KHNP REVISED RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION APR1400 Design Certification Korea Electric Power Corporation / Korea Hydro & Nuclear Power Co., LTD Docket No.52-046 RAI No.:

420-8482 SRP Section:

19.03 - Beyond Design Basis External Event (APR1400)

Application Section:

19.3 Date of RAI Issue:

02/29/2016 Question No. 19.03-36 NRC Commission paper SECY-12-0025 stated that the NRC staff expected new reactor design certification applications to address the Commission-approved Fukushima actions in their applications to the fullest extent practicable. In performing its review of the APR1400 design certification application, the NRC staff followed the guidance for satisfying the Commission directives regarding BDBEE mitigation strategies in Japan Lesson-Learned Project Directorate JLD-ISG-2012-01, Revision 0, which endorsed with clarifications the methodologies described in NEI 12-06, Revision 0. The guidance in JLD-ISG-2012-01 describes one acceptable approach for satisfying the Commission directives regarding BDBEE mitigation strategies (i.e.,

Order EA-12-049). TR APR1400-E-P-NR-14005-P, Rev. 0 provides details regarding mitigating strategies and design enhancements to meet Near-Term Task Force (NTTF) recommendations, NRC orders, and agency guidance related mitigation strategy during Beyond Design Basis External Events (BDBEE).

NEI 12-06, Revision 0 guidance states that unlike 50.54(hh)(2), the intention of this guidance is to have permanent, installed connection points for portable fluid and electrical equipment.

Electrical diversity can be accomplished by providing a primary and alternate method to repower key equipment and instruments utilized in FLEX strategies. At a minimum, the primary connection point should be an installed connection suitable for both the on-site and off-site equipment. The secondary connection point may require reconfiguration (e.g., removal of valve bonnets or breaker) if it can be shown that adequate time is available and adequate resources are reasonably expected to be available to support the reconfiguration. Both the primary and alternate connection points do not need to be available for all applicable hazards, but the location of the connection points should provide reasonable assurance of at least one connection being available. TR, APR1400-E-P-NR-14005-P, Revision 0, Table 5-9, Conformance with NEI 12-06," Rev. 0, states that the appropriate standard mechanical and electrical connections need to be specified and the COL applicants are responsible to establish a means to ensure the necessary resources are available from offsite. Table 5-9 (8 of 20) also states that connections for primary and secondary FLEX pumps, and mobile GTGs, are

19.03-36_Rev. 2 - 2 / 3 KEPCO/KHNP provided on the outside of the exterior wall of the auxiliary building, thereby providing reasonable assurance of the accessibility of personnel and equipment.

1.

Provide the COL item that will be used by the COL applicant to ensure the appropriate connection points for the electrical equipment, including voltages and classification.

2.

Section 5.1.2.6.1.1 states that the provisions to connect these GTGs are incorporated into the design. Please discuss what the provisions are.

Response - (Rev. 2)

The mobile generators are connected to the Class 1E onsite ac power system train A or B based on each phase of the mitigation strategies for BDBEEs. During phase 1 (or 2), the appropriate electrical connections between local equipment and FLEX equipment will be accomplished to support phase 2 (or 3) according to the FLEX strategies and its associated provisions.

The following provides responses to each corresponding question the staff asked.

1.

In order for the COL applicant to ensure the appropriate connection points for the electrical equipment including locations, voltages, and classification, KHNP will add a COL item in the DCD Tier 2, Section 19.3.

2.

As described in DCD Tier 2, Subsection 8.3.1.1, the mobile generators supply power to the Class 1E buses through connection boxes, which are watertight type. The connection boxes are installed in the entry and exit of the auxiliary building taking into account the accessibility of the onsite 480V mobile GTG and 4.16 kV mobile generator mobilized from offsite.

With regard to electrical connections, power cables between the connection boxes and incoming circuit breakers of the Class 1E buses are designed as permanent installations and the temporary cables will be connected between the mobile generators and connection boxes according to the APR1400 FLEX strategies.

Further discussion on the design aspects of the mobile generators is provided in the response to RAI 61-7984, Question No. 08.03.01-5 (Reference KHNP submittal MKD/NW-15-0131L, dated September 8, 2015, ML15251A244).

Supplemental Response The number of COL item which was added in the mark-up of previous response has been changed from COL 19.3(10) to COL 19.3(7).

19.03-36_Rev. 2 - 3 / 3 KEPCO/KHNP Impact on DCD The changes that were proposed in the original response to this RAI have been incorporated into Revision 2 of the DCD; therefore, only the pages containing proposed changes as a result of Revisions 1 and 2 of this response are included in the Attachment.

All DCD markups including response to RAI 61-7984 Question 08.03.01-5 Rev.1 related to this change are enclosed in this RAI response.

DCD Tier 1, Figure 2.6.1-1 and DCD Tier 2, Table 1.8-2, Figure 8.1-1, Subsections 8.3.1.1, 8.3.1.1.3.4, Figure 8.3.1-1, and Subsections 8.3.3, 19.3.2.3.1.1, 19.3.2.3.1.3, 19.3.2.3.4, and 19.3.4 will be revised as shown in the Attachment.

Impact on PRA There is no impact on the PRA.

Impact on Technical Specifications There is no impact on the Technical Specifications.

Impact on Technical/Topical/Environmental Reports There is no impact on any Technical, Topical, or Environmental Report.

APR1400 DCD TIER 1 2.6-15







TO MAIN GENERATOR (DIV.I)

NO NON-CLASS 1E 13.8KV SWGR UNIT AUX. XFMR 1N H

Y X

13.8KV 4.16KV NON-CLASS 1E 13.8KV SWGR 13800-480V TR 480V LC MCC 480V LC 13800-480V TR MCC 480V LC 4160-480V TR MCC NON-CLASS 1E 4.16KV SWGR NO NO CLASS 1E 4.16KV SWGR 1B 480V LC 1B 4160-480V TR 480V LC 1D 4160-480V TR MCC 1D, 2D, 3D, 4D NO NO NO NO STAND-BY AUX. XFMR 2N 13.8KV 4.16KV CLASS 1E 4.16KV SWGR 1D Y

X H

TO SWITCHYARD 4160-480V TR PREMANENT NON-SAFETY 4.16KV SWGR 1N 4160-480V TR PRESS HTRS BACK-UP GROUP B-2 TO 480V LC (DIV.I)

NON-CLASS 1E 4.16KV AAC SWGR 3N 480V AAC LC 4160-480V TR NO MCC NO NO 1B 1N MAIN GEN.

GEN. CIRCUIT BRK.

A TO UNIT AUX. XFMR (DIV.II)

NO NON-CLASS 1E 13.8KV SWGR UNIT AUX. XFMR 1M H

EXCITATION XFMR EXCITATION SYSTEM Y

X 13.8KV 4.16KV NON-CLASS 1E 13.8KV SWGR 13800-480V TR 480V LC MCC NON-CLASS 1E 4.16KV SWGR NO NO CLASS 1E 4.16KV SWGR 1A 480V LC 1A 4160-480V TR MCC 1A, 2A, 3A, 4A, 5A NO TO 480V LC (DIV.II) 480V LC 2 4160-480V TR MCC 1C, 2C, 3C, 4C NO NO NO MAIN XFMR TO SWITCHYARD STAND-BY AUX. XFMR 2M 13.8KV 4.16KV CLASS 1E 4.16KV SWGR 1C Y

X H

TO SWITCHYARD 4160-480V TR MCC PERMANENT NON-SAFETY 4.16KV SWGR 1M 4160-480V TR PRESS HTRS BACK-UP GROUP B-1 480V LC 13800-480V TR MCC NO NO NO TO AAC SWGR (DIV.II) 1M 480V LC 4160-480V TR MCC NO 480V LC MCC 1B, 2B, 3B, 4B, 5B 480V LC MCC DIV.I NON-CLASS 1E CLASS 1E DIV.II NON-CLASS 1E CLASS 1E NON-CLASS 1E TO AAC SWGR TO AAC SWGR (DIV. II)

TO AAC SWGR M

RC PUMP 1A, 2A CONDENSATE PUMP A FW BOOSTER A, C CW PUMP A, C, E CENTRAL CHILLER 01, 02 CENTRAL CHILLER WATER PUMP 1 TGB CCW PUMP 1 CS PUMP 1 SI PUMP 3 ESW PUMP 2A CCW PUMP 2A ESS CHILLER 02A COOLING TOWER FAN 2A RC PUMP 1B, 2B CONDENSATE PUMP B, C FW BOOSTER B CW PUMP B, D, F START-UP FW PUMP CENTRAL CHILLER 03, 04 CENTRAL CHILLER WATER PUMP 2 TGB CCW PUMP 2 SC PUMP 2 SI PUMP 2 ESW PUMP 1B AF PUMP B CCW PUMP 1B ESS CHILLER 01B CHARGING PUMP 2 COOLING TOWER FAN 1B CS PUMP 2 SI PUMP 4 ESW PUMP 2B CCW PUMP 2B ESS CHILLER 02B COOLING TOWER FAN 2B SC PUMP 1 SI PUMP 1 ESW PUMP 1A AF PUMP A CCW PUMP 1A CHARGING PUMP 1 COOLING TOWER FAN 1A IPB 480V LC 1C M

M M

3 A

1A 1M 1N 1B 1A 3

M M

M M

M M

M M

NON-CLASS 1E NO NO NO NON-CLASS 1E CONNECTION BOX FOR 480V MOBILE GTG NO NO CONNECTION BOX FOR MOBILE GTG CONNECTION BOX FOR MOBILE GTG NO COOLING TOWER FAN GROUP COOLING TOWER FAN GROUP CONNECTION BOX FOR 480V MOBILE GTG NO ADMIN BLDG CLASS 1E EMERGENCY DIESEL GEN. 1D CLASS 1E EMERGENCY DIESEL GEN. 1B AAC GTG CLASS 1E EMERGENCY DIESEL GEN. 1C CLASS 1E EMERGENCY DIESEL GEN. 1A TO 4.16KV SWGR 1A TO 4.16KV SWGR 1B TO 4.16KV SWGR 1M TO 4.16KV SWGR 1N



Figure 2.6.1-1 AC Electrical Power Distribution System Rev. 2 GENERATOR RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (1/13)

APR1400 DCD TIER 2 1.8-19 Table 1.8-2 (15 of 39)

Item No.

Description COL 8.2(8)

The COL applicant is to determine the specific type of the OPDP system which properly address and meet the requirements of B.1. and B.2. of Branch Technical Position (BTP) 8-9, taking into account the site specific design configuration, installation condition, (field) performance testing and qualification status, and operation experiences of the OPDP system.

The COL applicant is also to provide the detailed design of the OPDP system selected for the APR1400 site.

The COL applicant is to perform a field simulation on the site specific design of the offsite power system to ensure that the settings of the OPDP system are adequate and appropriate for the site.

COL 8.2(9)

The COL applicant is to describe how testing is performed on the offsite power system components and identify the potential effects that must be considered during testing.

COL 8.2(10)

The COL applicant is to provide the required number of immediate access circuits from the transmission network.

COL 8.3(1)

The COL applicant is to provide and to design a mobile GTG and its support equipment.

COL 8.3(2)

The COL applicant is to provide a bus transfer study of the onsite power system. Based on the bus transfer study, the COL applicant is also to provide final relay selection and settings for the bus transfer.

COL 8.3(3)

The COL applicant is to establish procedures to monitor and maintain EDG reliability during plant operations to verify the selected reliability level target is being achieved as intended in RG 1.155.

COL 8.3(4)

The COL applicant is to describe and provide detailed ground grid and lightning protection.

COL 8.3(5)

The COL applicant is to conduct periodic inspection and testing of the protection devices for the EPA conductors. All circuit breakers for the EPA conductors shall be inspected and tested in 60 months, low voltage circuit breaker overcurrent protection devices for the EPA conductors shall be inspected and tested once per 18 months for 10 % of each type of circuit breakers, and overcurrent relay for medium voltage circuit breakers for the EPA conductors shall be inspected and tested once per 18 months.

COL 8.3(6)

The COL applicant is to provide testing, inspection, and monitoring programs for detecting insulation degradation of underground and inaccessible power cables within the scope of 10 CFR 50.65.

COL 8.3(7)

The COL applicant is to establish Administrative Program(s), including application of dedicated cable and raceway management database tool as necessary, which is (are) developed on the basis of the cable and raceway numbering system to efficiently manage cable routing and cable termination and verify that the cable design fulfills the acceptance criteria (i.e., separation, filling criteria, and ampacity).

COL 8.3(8)

The COL applicant is to provide the detailed design of the cathodic protection system as applicable to the site conditions.

COL 8.3(9)

The COL applicant is to provide protective device coordination.

COL 8.3(10)

The COL applicant is to provide the analysis and underlying assumptions used to demonstrate adequacy for insulation coordination of surge and lightning protection.





Rev. 2 their the 4.16 kV mobile generator and the 480V mobile GTGs RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (2/13)

APR1400 DCD TIER 2 1.8-42 Table 1.8-2 (38 of 39)

Item No.

Description COL 19.3(6)

The COL applicant is to confirm and ensure that the raw water tank and flow path to the FLEX equipment (structures, piping, components, and connections) are designed to be robust with respect to applicable hazards (e.g., seismic events, floods, high winds, and associated missiles).G COL 19.3(7)

The COL applicant is to provide site-specific details of the electrical connection points (including locations, accessibility, voltage level, and electrical classification) for the mobile GTGs.G COL 19.3(8)

The COL applicant is to ensure that all the connections (refer to Table 6-5 in Reference 5) for FLEX strategies located outside the buildings are accessible and protected from all applicable external hazards (e.g., seismic events, floods, high winds, and associated missiles).G COL 19.3(9)

The COL applicant is to address site-specific strategies to mitigate BDBEEs as specified in the NRC Order EA-12-049.G COL 19.3(10)

The COL applicant is to propose a License Condition to verify the development and implementation of the guidance, strategies, and programs for the mitigation strategies for ensuring core cooling, containment function, and spent fuel pool cooling capabilities during an extended loss of ac power event at an APR1400 nuclear power plant.

COL 19.3(11)

The COL applicant is to provide a description of the operational programs that will provide assurance of the functional capability of the pumps, valves, and dynamic restraints used in the mitigation strategies for ensuring core cooling, containment function, and spent fuel pool cooling capabilities during an extended loss of ac power event at an APR1400 nuclear power plant.

COL 19.3(12)

The COL applicant is to address SFP level instrumentation maintenance procedure development and perform training as specified in NRC Order EA-12-051.G COL 19.3(13)

The COL applicant is to address development of EOPs, SAMGs, and EDMGs that incorporate lessons learned from TEPCO's Fukushima Dai-Ichi nuclear power plant accident as addressed in SECY-12-0025.

COL 19.3(14)

The COL applicant is to address enhancement of the offsite communication system as specified in the NRC Request for Information pertaining to NTTF Recommendation 9.3.

COL 19.3(15)

The COL applicant is to address staffing for large-scale natural events as specified in the NRC RFI pertaining to NTTF Recommendation 9.3.

COL 19.4(1)

The COL applicant is to provide provision and procedure/guidance for implementing SFP strategies, including the minimum pump discharge pressure required to support the minimum flow requirements. All portable equipment is to be stored at least 91.44 m (100 yards) from the auxiliary building. The COL applicant is to specify the external water source(s) to be used.

COL 19.4(2)

The COL applicant is to provide fire fighting response strategy.

COL 19.4(3)

The COL applicant is to provide procedure/guidance for implementing the IRWST makeup strategy.

COL 19.4(4)

The COL applicant is to determine the portable DC power source and connection device to SG pressure and level indication panels.

5HY

480V mobile GTGs and the 4.16 kV mobile generator.

RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (3/13)

APR1400 DCD TIER 2 8.1-25 MAIN GEN 24KV GEN. CIRCUIT BRK.

TO UNIT AUX. XFMR 1N NO NON-CLASS 1E 13.8KV SWGR 1M RC PUMP 1A,2A M

UNIT AUX. XFMR 1M H

EXCITATION XFMR EXCITATION SYSTEM Y

X 13.8KV 4.16KV CONDENSATE PUMP A FW BOOSTER A,C CW PUMP A,C,E M

NON-CLASS 1E 13.8KV SWGR 2M 13800-480V XFMR 480V LC MCC 480V LC 13800-480V XFMR MCC BATT.

CHARGER (STAND-BY)

TO 250V DC CONT.

CENTER REG. XFMR 480-120V, 1

NO TGBCCW PUMP 1 M

BATT.

CHARGER (STAND-BY)

BATT.

CHARGER TO 125V DC CONT.

CENTER M

480V LC A

M REG. XFMR 480-120V, 1

120V AC DISTR. PNL INVERTER MCC NON-CLASS 1E 4.16KV SWGR 2M NO 125V DC CONT.

CENTER NO CLASS 1E 4.16KV SWGR 1A SC PUMP 1 SI PUMP 1 ESW PUMP 1A AF PUMP A CCW PUMP 1A ESS CHILLER 1A CHARGING PUMP 1 COOLING TOWER FAN 1A M

480V LC 1A 4160-480V XFMR MCC 1A BATT.

CHARGER 1A REG. XFMR 1A 480-120V, 1 480V LC 2(SWING BUS) 125V DC CONT.

CENTER 1A 480V LC 1C 4160-480V XFMR MCC 1C REG. XFMR 1C 480-120V, 1 NO NO NO CS PUMP 1 SI PUMP 3 ESW PUMP 2A CCW PUMP 2A ESS CHILLER 2A COOLING TOWER FAN 2A M

IPB 13.8KV 4.16KV CLASS 1E 4.16KV SWGR 1C Y

X H

480V LC 4160-480V XFMR MCC CENTRAL CHILLER 1,2 CENTRAL CHILLED WATER PUMP 1 M

PERMANENT NON-SAFETY 4.16KV SWGR 1M 4160-480V XFMR PRESS HTRS BACK-UP GROUP B-1 MCC NO NO M

BATT.

CHARGER 1C M

BATT.

CHARGER 2A (STAND-BY)

BATT.

CHARGER 2C (STAND-BY) 4160-480V XFMR 480V LC 4160-480V XFMR MCC NO NO NO NO 24KV NON-CLASS 1E TO STAND-BY AUX XFMR 2N MAIN XFMR CLASS 1E TRAIN A TRAIN C 125V DC CONT.

CENTER 1C NO TO 480V LC 1B NON-CLASS 1E SWITCHYARD SWITCHYARD NO TO AAC SWGR TO AAC SWGR A

M 120V AC DISTR. PNL A

M 120V AC DISTR. PNL A

M 120V AC DISTR. PNL INVERTER 1A INVERTER 1C INVERTER 125V DC BATTERY 125V DC BATTERY 1A 125V DC BATTERY 1C CONNECTION BOX FOR MOBILE GTG 1M 1

2 3

4 A

B A

B 5

1A AUX. CHARGING PUMP3 M

DUMMY BRK.

DUMMY BRK.

CONNECTION BOX FOR 480V MOBILE GTG NO NO COOLING TOWER FAN GROUP ADMIN BLDG Note

1) Simplified AC Power Distribution System.

Detailed drawing is provided in Figure 8.3.1-1.

(Note 1)

(Note 1)

(Note 1)

PLANT CLASS 1E EMERGENCY DIESEL GEN. 1A PLANT STAND-BY AUX. XFMR 2M CLASS 1E EMERGENCY DIESEL GEN. 1C Figure 8.1-1 Electric Power System Single-Line Diagram (Division I) (1 of 2)

Rev. 2 GENERATOR RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (4/13)

APR1400 DCD TIER 2 8.1-26 1

TO MAIN GENERATOR NO NON-CLASS 1E 13.8KV SWGR 1N RC PUMP 1B,2B M

UNIT AUX. XFMR 1N H

Y X

13.8KV 4.16KV CONDENSATE PUMP B,C FW BOOSTER B CW PUMP B,D,F START-UP FW PUMP M

NON-CLASS 1E 13.8KV SWGR 2N 13800-480V XFMR 480V LC MCC 480V LC 13800-480V XFMR MCC BATT.

CHARGER REG. XFMR 480-120V, 1 TGBCCW PUMP 2 M

480V LC 4160-480V XFMR MCC BATT.

CHARGER M

480V LC REG. XFMR 480-120V, 1 MCC NON-CLASS 1E 4.16KV SWGR 2N NO 125V DC CONTROL CENTER NO SC PUMP 2 SI PUMP 2 ESW PUMP 1B AF PUMP B CCW PUMP 1B ESS CHILLER 1B CHARGING PUMP 2 COOLING TOWER FAN 1B M

480V LC 1B 4160-480V XFMR BATT.

CHARGER 1B REG. XFMR 1B 480-120V, 1 125V DC CONT.

CENTER 1B 480V LC 1D 4160-480V XFMR MCC 1D BATT.

CHARGER 1D REG. XFMR 1D 480-120V, 1 125V DC CONT.

CENTER 1D NO NO NO CS PUMP 2 SI PUMP 4 ESW PUMP 2B CCW PUMP 2B ESS CHILLER 2B COOLING TOWER FAN 2B M

IPB STAND-BY AUX. XFMR 2N 13.8KV 4.16KV CLASS 1E 4.16KV SWGR 1D Y

X H

SWITCHYARD 480V LC 4160-480V XFMR MCC CENTRAL CHILLER 3,4 CENTRAL CHILLED WATER PUMP 2 M

PERMANENT NON-SAFETY 4.16KV SWGR 1N TO 480V LC 2 5

M TO STAND-BY BATT. CHARGER 250V DC CONT.

CENTER REG. XFMR 480-120V, 1 UPS BATT.

CHARGER F

125V DC CONT.

CENTER 3

NON-CLASS 1E 4.16KV AAC SWGR 3N 480V LC 4160-480V XFMR NO 1

N MCC 125V DC BATTERY 125V DC CONT.

CENTER NO NO NO M

M BATT.

CHARGER 2B (STAND-BY)

BATT.

CHARGER 2D (STAND-BY) 4160-480V XFMR MCC 1B BATT.

CHARGER NO NO 1

B 4160-480V XFMR PRESS HTRS BACK-UP GROUP B-2 MCC CLASS 1E 4.16KV SWGR 1B TRAIN B TRAIN D CLASS 1E NON-CLASS 1E NON-CLASS 1E NON-CLASS 1E 2

NO NO NO A

M 120V AC DISTR. PNL INVERTER A

M 120V AC DISTR. PNL INVERTER A

M 120V AC DISTR. PNL INVERTER 1B A

M 120V AC DISTR. PNL INVERTER 1D 120V AC DISTR. PNL U P S REG. XFMR 480-120V, 1 TG UPS 120V AC DISTR. PNL U P S 125V DC BATTERY 1D 125V DC BATTERY 1B 125V DC BATTERY 125V DC BATTERY 250V DC BATTERY MCC REG. XFMR 480-120V, 1 AAC UPS 120V AC DISTR. PNL U P S TO STAND-BY BATT. CHARGER CONNECTION BOX FOR MOBILE GTG 4

1N 1B F

E C

D C

D E

F 3

1 2

1B 1N 1A 1M NO CONNECTION BOX FOR 480V MOBILE GTG NO COOLING TOWER FAN GROUP TO CPB MCC TO AAC SWGR TO AAC SWGR K

FK (Note 1)

(Note 1)

(Note 1)

Note

1) Simplified AC Power Distribution System.

Detailed drawing is provided in Figure 8.3.1-1.

CLASS 1E EMERGENCY DIESEL GEN. 1B CLASS 1E EMERGENCY DIESEL GEN. 1D AAC GTG TO 4.16KV SWGR 1A TO 4.16KV SWGR 1B TO 4.16KV SWGR 1M TO 4.16KV SWGR 1N Figure 8.1-1 Electric Power System Single-Line Diagram (Division II) (2 of 2)

Rev. 2 GENERATOR RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (5/13)

APR1400 DCD TIER 2 8.3-1 8.3 Onsite Power Systems 8.3.1 AC Power Systems 8.3.1.1 Description The onsite ac power system includes standby power sources, distribution systems, and auxiliary supporting systems that are provided to supply power to safety-related equipment or equipment important to safety for all normal operating and accident conditions. There are four Class 1E emergency diesel generators (EDGs) and one non-Class 1E gas turbine generator (GTG). The alternate alternating current (AAC) source is used as a standby power source for the onsite ac power system. The four Class 1E EDGs provide backup power to the Class 1E 4.16 kV buses in the event of a loss of offsite power (LOOP). One Class 1E EDG is dedicated to the respective Class 1E 4.16 kV bus. The non-Class 1E AAC GTG provides backup power to the permanent non-safety (PNS) buses during a LOOP and the dedicated Class 1E 4.16 kV bus during a station blackout (SBO).

The Class 1E ac power system is supplied power from one 4.16 kV or one of two 480V mobile GTGs in case of a beyond-design-basis external event. The 4.16 kV mobile GTG is connected to the 4.16 kV switchgear 1A (or 1B), and the 480V GTG is connected to 480V load center 1A (or 1B). The connection box provided for the connection of a cable between the mobile GTG and the Class 1E bus is watertight. The connection box is installed in the entry and exit of the auxiliary building where the connection boxes are readily accessible to the mobile GTG. The COL applicant is to provide and to design a mobile GTG and its support equipment (COL 8.3(1)). In addition, Class 1E switchgear rooms are also designed with watertight exterior barriers and doors to prevent the inflow of floodwater.

The mitigation strategies for beyond-design-basis external events, which involve operation of the mobile generators, are described in Section 19.3 of Chapter 19.

The onsite power system consists of the Class 1E power system and the non-Class 1E power system. The onsite power system is normally powered from two unit auxiliary transformers (UATs). If the normal preferred power source from UATs is unavailable, all Class 1E and non-Class 1E buses are automatically transferred to the alternate preferred power source from standby auxiliary transformers (SATs) by the fast and residual transfer scheme. For the automatic fast transfer, the synchro-check relay for each bus is used to supervise the voltage difference between the switchgear bus and upstream of the alternate Rev. 2 mobile generator generator the 4.16 kV mobile generator or 480V mobile GTGs the 4.16 kV mobile generator and the 480V mobile GTGs their RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (6/13)

APR1400 DCD TIER 2 8.3-13

f.

Phase (negative phase sequence) unbalance

g. Diesel generator fail to start

h. Running unloaded

i.

Cranking

j.

Subsystem trouble (ac generator, fuel oil system, lube oil system, cooling water system, starting system, excitation loss, and miscellaneous).

8.3.1.1.3.4 Interlocks Each Class 1E 4.16 kV bus can be powered by either of the two offsite power sources or the Class 1E EDG of each train. In addition, each of train A and train B Class 1E 4.16 kV bus can also be powered by non-Class 1E AAC GTG or 4.16 kV mobile GTG.

a.

The interlock circuits of incoming breakers prevent parallel operation between normal and alternate preferred power supplies during manual transfer between UAT and SAT.

b. The EDG is permitted to operate in parallel with an offsite power source after synchronizing both sources during periodic testing.

c.

The incoming circuit breakers are manually closed after synchronizing the offsite power sources with the Class 1E 4.16 kV bus when the preferred power supply is restored from a LOOP or SBO event.

d. The electrical interlocks of the circuit breaker are provided to prevent the automatic closing of an EDG breaker onto an energized or faulted bus.

8.3.1.1.3.5 Permissive The EDG operational mode selection is provided at the EDG local control panel through a LOCAL/REMOTE selector switch and a NORMAL/MAINTENANCE selector switch.

Emergency start and emergency trip functions are not blocked by LOCAL mode selection.

Selection of the NORMAL mode also enables the selection of REMOTE/LOCAL mode switch. Selection of the MAINTENANCE mode blocks all automatic or manual Rev. 2 generator RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (7/13)

APR1400 DCD TIER 2 8.3-114 NO CLASS 1E 4.16KV SWGR SW01A NO NEUTRAL GRND XFMR

B C

A NO M

M M

M M

M SC PUMP 1 SI PUMP 1 ESW PUMP 1A CCW PUMP 1A M

ESS CHILLER 1A CHARGING PUMP 1 AF PUMP A 480V LC LC01C 4160-480V XFMR 01C MCC M

M M

M M

CNMT SPRAY PUMP 1 CCW PUMP 2A COOLING TOWER FAN 2A SI PUMP 3

ESS CHILLER 2A NO NEUTRAL GRND XFMR

B C

A NO CLASS 1E 4.16KV SWGR SW01C NO CLASS 1E 4.16KV SWGR SW01B NO NEUTRAL GRND XFMR

B C

A NO M

M M

M M

M SC PUMP 2 SI PUMP 2 ESW PUMP 1B CCW PUMP 1B M

ESS CHILLER 1B CHARGING PUMP 2 AF PUMP B 480V LC LC01B 4160-480V XFMR 01B MCC 4160-480V XFMR13N PRESS HTRS BACK-UP GROUP B-2 A

C B

A C

B B

C A

A C

B 480V LC LC01D 4160-480V XFMR 01D MCC M

M M

M M

CNMT SPRAY PUMP 2 ESW PUMP 2B CCW PUMP 2B SI PUMP 4 ESS CHILLER 2B NO NEUTRAL GRND XFMR

B C

A NO CLASS 1E 4.16KV SWGR SW01D TO 480V LC02 DIVISION I DIVISION II 27 480V LC LC01A 4160-480V XFMR 01A MCC NO TO 480V LC01B 480V LC02 (SWING BUS)

B C

A A

C B

4160-480V XFMR 13M PRESS HTRS BACK-UP GROUP B-1 A

C B

A C

B TRAIN C TRAIN A NON-CLASS 1E 27 27 27 TRAIN B TRAIN D NON-CLASS 1E Class 1E 4.16 kV AC Power System TO UAT 01M TO SAT 02M TO AAC SWGR 03N TO UAT 01M TO SAT 02M TO UAT 01N TO SAT 02N TO AAC SWGR 03N TO UAT 01N TO SAT 02N MC01A,02A 03A,04A,05A MC01C,02C 03C,04C MC01B,02B 03B,04B,05B MC01D,02D 03D,04D B

C A

A C

B B

C A

A C

B TO CONNECTION BOX FOR MOBILE GTG TO CONNECTION BOX FOR MOBILE GTG MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR MFR 1B 1A MFR MFR DUMMY BRK.

(MANUAL)

TO CONNECTION BOX FOR MOBILE GTG TO CONNECTION BOX FOR MOBILE GTG NO NO NO NO M

COOLING TOWER FAN 1A MFR M

ESW PUMP 2A MFR M

COOLING TOWER FAN 1B MFR M

COOLING TOWER FAN 2B MFR Figure 8.3.1-1 Onsite AC Electrical Power System (3 of 3)

Rev. 2 GENERATOR RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (8/13)

APR1400 DCD TIER 2 8.3-58 8.3.2.3.7 Grounding The dc power system is designed to be an ungrounded system, which enhances the system reliability and service continuity because a single ground has no adverse effect on the system operation. Each train has a ground detector to isolate and monitor the fault area.

The ground detector has an alarm in the MCR to monitor constant grounding and recording.

The ground detector has high sensitivity.

8.3.3 Combined License Information COL 8.3(1)

The COL applicant is to provide and to design a mobile GTG and its support equipment.

COL 8.3(2)

The COL applicant is to provide a bus transfer study of the onsite power system. Based on the bus transfer study, the COL applicant is also to provide final relay selection and settings for the bus transfer.

COL 8.3(3)

The COL applicant is to establish procedures to monitor and maintain EDG reliability during plant operations to verify the selected reliability level target is being achieved as intended in RG 1.155.

COL 8.3(4)

The COL applicant is to describe and provide detailed ground grid and lightning protection.

COL 8.3(5)

The COL applicant is to conduct periodic inspection and testing of the protection devices for the EPA conductors. All circuit breakers for the EPA conductors shall be inspected and tested in 60 months, low voltage circuit breaker overcurrent protection devices for the EPA conductors shall be inspected and tested once per 18 months for 10 % of each type of circuit breakers, and overcurrent relay for medium voltage circuit breakers for the EPA conductors shall be inspected and tested once per 18 months.

COL 8.3(6)

The COL applicant is to provide testing, inspection, and monitoring programs for detecting insulation degradation of underground and inaccessible power cables within the scope of 10 CFR 50.65.

COL 8.3(7)

The COL applicant is to establish Administrative Program(s), including application of dedicated cable and raceway management database tool as Rev. 2 their the 4.16 kV mobile generator and the 480V mobile GTGs RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (9/13)

APR1400 DCD TIER 2 19.3-6 Two primary high-head FLEX pumps and three secondary FLEX pumps are provided to meet the N+1 requirement.

Additionally, as RCS cooldown continues and RCS pressure decreases to the designed setpoint of safety injection tank (SIT) injection, the SIT automatically discharges 4,000 ppm borated water into the RCS for boration and inventory makeup.

Phase 3: after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> In Phase 3, offsite resources, including a 4.16 kV mobile GTG, fuel, and cooling water can be assumed to be available for long-term coping with the BDBEE. The 4.16 kV mobile GTG will be used to restore Train A or B of the 4.16 kV Class 1E power system. The plant will be brought to cold shutdown, using the shutdown cooling system (SCS), if the ultimate heat sink (UHS) is available after 4.16 kV Class 1E power is restored. If not, the plant is maintained at the same safe shutdown state as in Phase 2.

In this phase, the primary and secondary makeup water sources and fuel oil for the mobile GTGs will be refilled from offsite resources.

19.3.2.3.1.2 Low-Power Operation with SGs available Strategy for Mode 1 through Mode 3 The NCC analysis result for the full-power FLEX strategy is still valid for operation in modes 1 through 3,i.e., lower-power operation, startup, and hot standby conditions, because it covers various states of the plant,including full-power operation through hot shutdown condition. Therefore, the same FLEX strategy as in thefull-power operation can be also applied to the modes 1 through 3 operations.

Strategy for Mode 4 and Mode 5 with SGs Available In these operation modes, the SCS normally maintains the RCS between 176.67 °C (350 °F)

(hot shutdown) and 54.44 °C (130 °F) (cold shutdown), while the SGs are still available.

If the event an ELAP concurrentwith LUHS occurs during these operation modes, the RCS is heated up and pressurized due to the loss of the SCS.

If the RCS temperature is initially below the maximum RCS temperature requiring low-temperatureoverpressurization protection (LTOP), i.e., 136.11 °C (277 °F), the RCS pressure can be maintained below theLTOP protection limiting pressure of 43.94 kg/cm2A Rev. 2 generator generator RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (10/13) 4.16 kV mobile generator and the 480V mobile GTG RAI 420-8482 - Question 19.03-36_Rev.2

APR1400 DCD TIER 2 19.3-8 head FLEX pump must be aligned to take suction from the acceptable coolant source and deliver the coolant to the vessel. A mobile GTG is prepared to connect to Train A or Train B 480 V Class 1E ac power system to supply power to Class 1E battery. Two primary low-head FLEX pumps are provided to meet the N+1 requirement. The COL applicant is to address the details of storage location for FLEX equipment (COL 19.3(4)). In Phase 3, the 4.16 kV mobile GTG, fuel, and cooling water are available from offsite for long-term coping for the event. The 4.16 kV mobile GTG is used to restore Train A or Train B of 4.16 kV Class 1E power system. If the SCS is operable when the 4.16 kV Class 1E power is restored, the plant is cooled down to and maintained at cold shutdown by resuming the SCS operation. If not, the plant is maintained at the same safe shutdown state as in Phase 2, using the primary FLEX pump for RCS inventory makeup. In this phase, the primary and secondary makeup water sources and fuel oil for the mobile GTGs will be refilled from offsite resources. The COL applicant is to develop shutdown risk processes and procedures, and verify ability to deploy FLEX equipment to provide core cooling in shutdown operation with SGs not available (COL 19.3(17)).

Indication of Core Coverage The operator can monitor the RCS level in MCR via flat panel display (FPD) from qualified indication and alarm system - P (QIAS-P). Coolant level during the reduced inventory operations is measured by the permanent refueling water level indication system (PRWLIS), the local refueling water level indication system (LRWLIS), and the ultrasonic level measurement system (ULMS). The PRWLIS consists of the wide range (WR) level instrument and the narrow range (NR) level instrument. Each of two trains provides the means of monitoring water level of each RCS loop to the MCR during reduced RCS inventory operations. The PRWLIS (WR) indicates coolant level between 10% level of the pressurizer and the bottom of the hot leg. It provides level indication to the MCR without alarm. The PRWLIS (NR) indicates coolant level between the top of the hot leg and 2 in above the bottom of the hot leg. It provides level indication and Low, Low-Low and High alarms to the MCR. The LRWLIS (Sight Glasses) indicates coolant level between 3 ft below the reactor vessel flange and the bottom of the hot leg. The LRWLIS provide level indication and Low and Low-Low alarms to the MCR. The ULMS is installed temporarily on both hot legs to monitor coolant level of hot leg during mid-loop operation. The ULMS provides indication, audible and visible alarms which consist of High, Low, and Low-Low alarms, and record functions to the MCR. Core exit temperature (CET) also can be Rev. 2 generator generator RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (11/13) 4.16 kV mobile generator and the 480V mobile GTG RAI 420-8482 - Question 19.03-36_Rev.2

APR1400 DCD TIER 2 19.3-13 The detailed design of the raw water tank related with site specific data is the responsibility of the COL applicant. The COL applicant is to confirm, satisfy, or fulfill the specific design functional requirements of raw water tank including the associated instrument, capacity, location, flow path to on-site, the valve pit connected to FLEX equipment, and any other design features as described in DCD Section 19.3 in support of BDBEE mitigation strategies (COL 19.3(5)). The COL applicant is to confirm and ensure that the raw water tank and flow path to the FLEX equipment (structures, piping, components, and connections) are designed to be robust with respect to applicable hazards (e.g., seismic events, floods, high winds, and associated missiles) (COL 19.3(6)).

The COL applicant is to provide site-specific details of the electrical connection points (including locations, accessibility, voltage level, and electrical classification) for the mobile GTGs (COL 19.3 (7)).

The COL applicant is to ensure that all the connections (refer to Table 6-5 in Reference 5) for FLEX strategies located outside the buildings are accessible and protected from all applicable external hazards (e.g., seismic events, floods, high winds, and associatedmissiles)

(COL 19.3 (8)).

Also, the COL applicant is to address site-specific strategies to mitigate BDBEEs as specified in NRC Order EA-12-049 (COL 19.3(9)), including but not limited to the following:

a.

Evaluation of site-specific external hazards

b.

Determination and protection of portable equipment including final design head for FLEX pumps

c.

Providing means for acquisition, staging, and installation of equipment

d.

Establishing means for maintaining and testing of portable equipment

e.

Establishing procedures and guidance on mitigation of BDBEEs

f.

Establishing training of personnel to the developed strategies and procedures The COL applicant is to propose a License Condition to verify the development and implementation of the guidance, strategies, and programs for the mitigation strategies for ensuring core cooling, containment function, and spent fuel pool cooling capabilities during 5HY

480V mobile GTGs and the 4.16 kV mobile generator RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (12/13)

APR1400 DCD TIER 2 19.3-17 COL 19.3(3)

The COL applicant is to develop the details for offsite resources.

COL 19.3(4)

The COL applicant is to address the details of selecting suitable storage locations for FLEX equipment that provide reasonable protection during specific external events as provided in NEI 12-06 guidance Sections 5 through 9, and the details of the guidance for storage of FLEX equipment provided in the Technical Report (Reference 5) Section 6.2.9.

COL 19.3(5)

The COL applicant is to confirm, satisfy, or fulfill the specific design functional requirements of raw water tank including the associated instrument, capacity, location, flow path to on-site, the valve pit connected to FLEX equipment, and any other design features as described in DCD Section 19.3 in support of BDBEE mitigation strategies.

COL 19.3(6)

The COL applicant is to confirm and ensure that the raw water tank and flow path to the FLEX equipment (structures, piping, components, and connections) are designed to be robust with respect to applicable hazards (e.g., seismic events, floods, high winds, and associated missiles).

COL 19.3(7)

The COL applicant is to provide site-specific details of the electrical connection points (including locations, accessibility voltage level, and electrical classification) for the mobile GTGs.

COL 19.3(8)

The COL applicant is to ensure that all the connections (refer to Table 6-5 in Reference 5) for FLEX strategies located outside the buildings are accessible and protected from all applicable external hazards (e.g., seismic events, floods, high winds, and associated missiles).

COL 19.3(9)

The COL applicant is to address site-specific strategies to mitigate BDBEEs as specified in the NRC Order EA-12-049.

COL 19.3(10) The COL applicant is to propose a License Condition to verify the development and implementation of the guidance, strategies, and programs for the mitigation strategies for ensuring core cooling, containment function and spent fuel pool cooling capabilities during an extended loss of ac power event at an APR1400 nuclear power plant.

5HY

480V mobile GTGs and the 4.16 kV mobile generator.

RAI 420-8482 - Question 19.03-36_Rev.1 RAI 420-8482 - Question 19.03-36_Rev.2 Attachment (13/13)