Text

Revised Request for License Amendment and Exemption: Ventilation System Changes (LAR-16-030R1)
	ML17243A444
Person / Time
Site:	Vogtle
Issue date:	08/31/2017
From:	Whitley B; Southern Nuclear Operating Co
To:	; Document Control Desk, Office of New Reactors
References
	LAR-16-030R1, ND-17-1499
	Download: ML17243A444 (60)
	v • d • e

B. H. Whitley Southern Nuclear Director Operating Company, Inc.

Regulatory Affairs 42 Inverness Center Parkway Birmingham, AL 35242 Tel 205.992.7079 Fax 205.992.5296 Page 1 of 20 August 31, 2017 Docket Nos.: 52-025 ND-17-1499 52-026 10 CFR 50.90 10 CFR 52.63 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001 Southern Nuclear Operating Company Vogtle Electric Generating Plant Units 3 and 4 Revised Request for License Amendment and Exemption:

Ventilation System Changes (LAR-16-030R1)

Ladies and Gentlemen:

Pursuant to 10 CFR 52.98(c), and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC), the licensee for Vogtle Electric Generating Plant (VEGP)

Units 3 and 4, requested an amendment to the Combined Licenses (COLs) for VEGP Units 3 and 4, COL Numbers NPF-91 and NPF-92, respectively, by SNC Letter ND-16-2452, dated December 9, 2016 [ADAMS Accession No. ML16344A411]. The SNC-proposed departures consisted of changes to various plant-specific Tier 1 (and COL Appendix C) information and Tier 2 material contained within the Updated Final Safety Analysis Report (UFSAR) to modify design details of the containment recirculation cooling system (VCS) and the radiologically controlled area ventilation system (VAS). Pursuant to the provisions of 10 CFR 52.63(b)(1), an exemption from elements of the design as certified in the 10 CFR Part 52, Appendix D, design certification rule was also requested for the plant-specific Tier 1 material departures.

On February 15, 2017, the Nuclear Regulatory Commission (NRC) issued a draft Request for Additional Information (RAI) letter [ML17046A045] to SNC regarding LAR-16-030. These draft RAI questions were discussed in the NRC Public Meeting on March 9, 2017 [ML17074A592]. As a result of the draft RAI and the Public Meeting discussions, SNC began preparing a revision to LAR-16-030. However, due to delays in revising the calculations which support the revision to LAR-16-030, SNC withdrew LAR-16-030 by letter ND-17-1179, dated June 28, 2017

[ML17179A261]. The revisions to the supporting calculations are now complete, and SNC is hereby replacing the original submittal of LAR-16-030 in total with this submittal, LAR-16-030R1.

Differences between LAR-16-030 and LAR-16-030R1 include changes to the LAR scope, technical evaluation, and environmental considerations; differences are indicated by revision bars in the right hand margin.

U.S. Nuclear Regulatory Commission ND-17-1499 Page 2 of 5 The proposed departures consist of changes to plant-specific Tier 1 (and COL Appendix C)

Tables 2.7.5-1, 2.7.5-2, and 2.7.7-3 and associated UFSAR text, tables, and figures related to:

1) Modifying the configuration of the containment recirculation fan coil unit assemblies of the VCS, and revising the values for the various design parameters affected by this reconfiguration,

2) Adding a fourth pressure differential indicator to the VAS to be located in the auxiliary building component cooling system valve room,

3) Reducing the total ventilation flow provided through the VAS fuel handling area ventilation subsystem as a result of a reduction in heat loads in the areas serviced by the VAS, and

4) Updating the radionuclide specific maximum airborne radioactivity concentrations in the auxiliary building, including the fuel handling area, to reflect the changes in ventilation flow rates as well as other input assumptions.

provides the description, technical evaluation, regulatory evaluation (including the Significant Hazards Consideration determination), and environmental considerations for the proposed changes in the License Amendment Request (LAR). provides the background and supporting basis for the requested exemption. identifies the requested changes and provides markups depicting the requested changes to the affected licensing basis documents.

This letter contains no regulatory commitments. This letter has been reviewed and confirmed to not contain security-related information.

SNC requests staff approval of this license amendment and exemption by November 30, 2018 to support installation of VCS ventilation equipment. Delayed approval of this licensing request could result in delay of the associated construction activity and subsequent dependent construction activities. SNC expects to implement the proposed amendment (through incorporation into the licensing basis documents; e.g., the UFSAR) within 30 days of the approval of the requested changes.

In accordance with 10 CFR 50.91, SNC is notifying the State of Georgia of this LAR by transmitting a copy of this letter and enclosures to the designated State Official.

Should you have any questions, please contact Mr. Adam G. Quarles at (205) 992-7031.

U.S. Nuclear Regulatory Commission N0-17-1499 Page 3 of5 I declare under penalty of perjury that the foregoing is true and correct. Executed on the 31st of August 2017.

Respectfully submitted, Brian H. Whitley Regulatory Affairs Director Southern Nuclear Operating Company

Enclosures:

1)

2)

3)

Vogtle Electric Generating Plant (VEGP) Units 3 and 4 - Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Vogtle Electric Generating Plant (VEGP) Units 3 and 4 - Exemption Request:

Ventilation System Changes (LAR-16-030R1)

Vogtle Electric Generating Plant (VEGP) Units 3 and 4 - Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

U.S. Nuclear Regulatory Commission ND-17-1499 Page 4 of 5 cc:

Southern Nuclear Operating Company / Georgia Power Company Mr. S. E. Kuczynski (w/o enclosures)

Mr. M. D. Rauckhorst Mr. D. G. Bost (w/o enclosures)

Mr. M. D. Meier (w/o enclosures)

Mr. D. H. Jones (w/o enclosures)

Mr. D. L. McKinney (w/o enclosures)

Mr. T. W. Yelverton (w/o enclosures)

Mr. B. H. Whitley Mr. J. J. Hutto Mr. C. R. Pierce Ms. A. G. Aughtman Mr. D. L. Fulton Mr. M. J. Yox Mr. E. W. Rasmussen Mr. J. Tupik Mr. W. A. Sparkman Ms. A. C. Chamberlain Mr. M. K. Washington Ms. A. L. Pugh Mr. J. D. Williams Document Services RTYPE: VND.LI.L00 File AR.01.02.06 Nuclear Regulatory Commission Mr. W. Jones (w/o enclosures)

Ms. J. Dixon-Herrity Mr. C. Patel Ms. J. M. Heisserer Mr. B. Kemker Mr. G. Khouri Ms. S. Temple Ms. V. Ordaz Mr. T.E. Chandler Ms. P. Braxton Mr. T. Brimfield Mr. C. J. Even Mr. A. Lerch State of Georgia Mr. R. Dunn

U.S. Nuclear Regulatory Commission ND-17-1499 Page 5 of 5 Oglethorpe Power Corporation Mr. M. W. Price Mr. K. T. Haynes Ms. A. Whaley Municipal Electric Authority of Georgia Mr. J. E. Fuller Mr. S. M. Jackson Dalton Utilities Mr. T. Bundros Westinghouse Electric Company, LLC Mr. R. Easterling (w/o enclosures)

Mr. G. Koucheravy (w/o enclosures)

Mr. P. A. Russ Mr. M. L. Clyde Ms. K. Chesko Mr. D. Hawkins Other Mr. S. W. Kline, Bechtel Power Corporation Ms. L. A. Matis, Tetra Tech NUS, Inc.

Dr. W. R. Jacobs, Jr., Ph.D., GDS Associates, Inc.

Mr. S. Roetger, Georgia Public Service Commission Ms. S. W. Kernizan, Georgia Public Service Commission Mr. K. C. Greene, Troutman Sanders Mr. S. Blanton, Balch Bingham Mr. R. Grumbir, APOG NDDocumentinBox@duke-energy.com, Duke Energy Mr. S. Franzone, Florida Power & Light

Southern Nuclear Operating Company ND-17-1499 Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Revised Request for License Amendment:

Ventilation System Changes (LAR-16-030R1)

(This Enclosure consists of 24 pages, including this cover page.)

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 2 of 24 Table of Contents

1.

SUMMARY

DESCRIPTION

2. DETAILED DESCRIPTION and TECHNICAL EVALUATION

3. TECHNICAL EVALUATION (Included in Section 2)

4. REGULATORY EVALUATION 4.1.

Applicable Regulatory Requirements/Criteria 4.2.

Precedent 4.3.

Significant Hazards Consideration Determination 4.4.

Conclusions

5. ENVIRONMENTAL CONSIDERATIONS

6. REFERENCES

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 3 of 24 Pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC) hereby requests an amendment to Combined License (COL) Nos.

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

1.

SUMMARY

DESCRIPTION The proposed changes revise the Combined Licenses (COLs) concerning the design details of the containment recirculation cooling system (VCS) and radiologically controlled area ventilation system (VAS). These proposed changes include the following:

A. The design of the VCS as described in Revision 19 of the AP1000 Design Control Document (DCD) was based upon the approved design of the VCS for the Westinghouse AP600 plant. However, final design of the VCS has resulted in proposed changes to the layout and sizing of the containment recirculation fan coil unit assemblies and associated ductwork, and changes to the total required design air flow rates and total design cooling and heating requirements. This includes proposed changes to the nominal design values for normal and low speed air flow rates, cooling capacity, chilled water flow rate, heating capacity, hot water flow rate, and supply air temperature for normal power operation for the containment recirculation fan coil unit assemblies.

B. A change is proposed to add a fourth VAS pressure differential instrument, numbered as VAS-033, providing indication, control, and alarm functions for the auxiliary building component cooling water system (CCS) valve room (Room 12561) while the exhaust flow path is aligned to the containment air filtration system (VFS) filtered exhaust. This provides pressure differential monitoring and control for the auxiliary building CCS valve room, which is an area of the auxiliary building that is physically remote and separate from the currently monitored and controlled areas. The existing pressure differential instrument VAS-033 for the auxiliary building middle annulus is renumbered as VAS-034.

C. Based on final calculations of heat loads in the areas serviced by the VAS, the required supply and exhaust airflows for the VAS are changed. This results in proposed changes to the required VAS nominal design supply air flow rate and total nominal design ventilation flow rates provided through the auxiliary building, including the fuel handling area. As a result, the calculations for determining the radionuclide specific maximum airborne radioactivity concentrations in the auxiliary building, including the fuel handling area, are revised. This includes an update to parameters and assumptions used for calculating fuel handling area and auxiliary building airborne radioactivity concentrations based on design finalization of the affected ventilation systems and other changed inputs.

The requested amendment requires changes to the UFSAR in the form of departures from the plant-specific Design Control Document (DCD) Tier 2 information (as detailed in Section 2), and involves changes to related COL Appendix C information, with corresponding changes to the associated plant-specific Tier 1 information. This enclosure requests approval of the license amendment necessary to implement the Tier 2 and COL Appendix C changes. Enclosure 2 requests the exemption necessary to implement the involved changes to the plant-specific DCD Tier 1 information.

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 4 of 24

2. DETAILED DESCRIPTION and TECHNICAL EVALUATION A. Change to Configuration of the Containment Recirculation Fan Coil Unit Assemblies The design of the VCS, as described in Revision 19 of the AP1000 DCD, was based upon the approved design of the VCS for the Westinghouse AP600 plant. However, final design of the VCS has resulted in changes to the layout and sizing of the containment recirculation fan coil unit assemblies and associated ductwork, and changes to the total required design air flow rates and total design cooling and heating requirements. Therefore, the VCS design as described in UFSAR Subsections 1.2.4.1, 9.4.6.2.1, 9.4.6.2.2, and 9.4.6.2.3, Table 9.4.6-1, and Figures 9.2.7-1 (Sheet 3) and 9.4.6-1, is proposed to be changed to modify the configuration of the containment recirculation fan coil unit assemblies. This involves a change to COL Appendix C (and plant-specific DCD Tier 1) Table 2.7.7-3 to add the two new containment recirculation fan coil unit assemblies (VCS-MS-01C and VCS-MS-01D).

The current design includes two containment recirculation fan coil unit assemblies with two fans each, with a divider plate between the two fans and two coils each on the north and south ends and four coils each on the east and west ends of each assembly plenum. The proposed design includes four separate containment recirculation fan coil unit assemblies with separate plenums, each with one fan with two cooling coils placed on each of the four sides of each assembly plenum. By using four separate containment recirculation fan coil unit assemblies with cooling coils on all four sides of each assembly plenum, the cooling surface area is increased without a significant increase in height. The configuration of the containment recirculation fan coil unit assemblies is modified to address changes in total required design air flow rates and total design cooling and heating requirements as a result of the final design of the VCS. This includes proposed changes to the nominal design values for normal and low speed air flow rates, cooling capacity, chilled water flow rate, heating capacity, hot water flow rate, and supply air temperature for normal power operation for the containment recirculation fan coil unit assemblies.

Licensing Basis Changes for Change to Configuration of the Containment Recirculation Fan Coil Unit Assemblies The following licensing basis changes are proposed to address the change to the configuration of the containment recirculation fan coil unit assemblies:

1. COL Appendix C (and plant-specific DCD Tier 1) is revised as follows:

a) Table 2.7.7-3 is revised to add the two new containment recirculation fan coil unit assemblies (VCS-MS-01C and VCS-MS-01D).

2. The UFSAR is revised as follows:

a) Tier 2 Subsections 1.2.4.1, 9.4.6.2.1, 9.4.6.2.2, and 9.4.6.2.3 are revised to change the number, location, and configuration of the containment recirculation fan coil unit assemblies, including the consistent use of the terms fan coil unit assemblies and fans where appropriate.

b) Tier 2 Figure 9.2.7-1 (Sheet 3) is revised to add the two new containment recirculation fan coil unit assemblies (VCS-MS-01C and VCS-MS-01D) to the units

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 5 of 24 served by the central chilled water system (VWS) high capacity subsystem, and by the hot water heating system (VYS).

c) Tier 2 Subsection 9.4.6.2.3 is revised to change the nominal design value for supply air temperature provided by the fan coil unit assemblies during normal power operation from 60°F to 70°F, consistent with supply air temperature used for the design finalization of the VCS and VWS high capacity subsystem.

d) Table 9.4.6-1 is revised to change the number and capacity of the containment recirculation fan coil unit assemblies, and to change nominal design values for the fans and coils per containment recirculation fan coil unit assembly. Additional editorial clarifications are provided to the title of the table, and to use consistent terminology including fan coil unit assemblies and fans where appropriate.

e) Figure 9.4.6-1 is revised to change the number and configuration of the containment recirculation fan coil unit assemblies.

Technical Evaluation of Change to Configuration of the Containment Recirculation Fan Coil Unit Assemblies As described in UFSAR Subsection 9.4.6, the nonsafety-related VCS functions to control air temperature and reduce humidity in the containment to provide a suitable environment for equipment operability during normal power operation, and for personnel accessibility and equipment operability during refueling and shutdown. The VCS also functions to maintain a homogeneous containment temperature and pressure during a containment integrated leak rate test (ILRT), and during and after a loss of plant alternating current (ac) if standby onsite ac power capacity is available, and to control the reactor cavity area average concrete temperature to less than prescribed limits. System equipment and ductwork whose failure could affect the operability of safety-related systems or components are designed to seismic Category II requirements. The remaining portion of the system is non-seismic. The VCS has no safety-related function.

The proposed changes do not adversely affect the design functions of the VCS described above. The proposed changes address the changes in total required design air flow rates and total design cooling and heating requirements as a result of the final design of the VCS, such that the design functions of the VCS are met. The change from two containment recirculation fan coil unit assemblies with 12 coils and two fans each with a common plenum with a divider plate between the two fans, to four containment recirculation fan coil unit assemblies with eight coils and one fan each with separate plenums, increases the air flow rate and cooling and heating surface area available for each containment recirculation fan coil unit to achieve the required cooling and heating capacity. In the proposed change, each of the four containment recirculation fan coil unit assemblies (which includes a single fan each) provides 50% capacity, which is the same as the current design in which each of the two containment recirculation fan coil unit assemblies (which includes two fans each) were specified as 100% capacity.

The proposed changes to the nominal design values for normal and low speed air flow rates for the VCS fans are acceptable, as the proposed containment recirculation fan coil unit assemblies are designed and tested to operate within the normal operating containment pressures as well as the higher containment pressures during a containment ILRT. The

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 6 of 24 normal air flow rate for the VCS fans is based on the revised total design cooling and heating requirements during normal power operations at full power, as are the revised cooling capacity, chilled water flow rate, heating capacity, and hot water flow rate requirements for the containment recirculation fan coil unit assemblies. Therefore, the proposed changes to the normal design values for cooling and heating capability for the proposed containment recirculation fan coil unit assemblies are acceptable. The low speed air flow rate is acceptable, as the containment air density is considerably higher during the performance of a containment ILRT. The existing cable penetration and associated cable tray layouts inside containment remain the same, as the power rating for the proposed VCS fans for both normal speed at normal operating containment pressure and low speed at the higher containment pressures during a containment ILRT remain within the design capability of the electrical power design.

With the increase in supply air temperature provided by the fan coil unit assemblies during normal power operation from 60°F to 70°F, the VCS continues to control air temperature and reduce humidity in the containment to provide a suitable environment for equipment operability during normal power operation. With the increase in normal supply air temperature, the VCS continues to function to control the reactor cavity area average concrete temperature to less than prescribed limits. The use of a supply air temperature of 70°F during normal power operation maintains the containment bulk area temperature under 120°F, the reactor cavity and nozzle gallery temperature under 135°F, and reactor cavity concrete temperature well below 150°F. In addition, established containment air room temperatures remain unchanged.

The VCS continues to meet the requirements during refueling and shutdown of controlling average bulk air temperature between 50°F and 70°F. In addition, the VCS continues to function to maintain a homogeneous containment temperature and pressure during a containment ILRT, and during and after a loss of the plant ac if standby onsite ac power capacity is available.

The proposed design of the four new separate containment recirculation fan coil unit assemblies continues to comply with the same codes and standards and materials of construction as the current design of the containment recirculation fan coil unit assemblies.

The containment recirculation fan coil unit assemblies are modularized to minimize physical constraints, lower fabrication costs, facilitate installation and limit interface points. Each containment recirculation fan coil unit assembly is of industrial type, rugged construction, factory assembled, and skid-mounted in a one-piece package.

The containment recirculation fan coil unit assemblies are designed, fabricated, and tested to meet the requirements of various design standards. The cooling coils are rated in accordance with American National Standards Institute (ANSI)/Air Conditioning and Refrigeration Institute (ARI) 410-1991, Forced-Circulation Air-Cooling and Air-Heating Coils.

The fans are designed and rated to standard air conditions in accordance with ANSI/Air Movement and Control Association (AMCA) 210-2007, Laboratory Method of Testing Fans for Aerodynamic Rating Purposes, ANSI/AMCA 211-2013, Certified Ratings Program -

Product Rating Manual for Fan Air Performance, and ANSI/AMCA 300-2014, Reverberant Room Methods for Sound Testing of Fans.

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 7 of 24 B. Addition of Fourth VAS Pressure Differential Instrument The VAS design as described in UFSAR Subsection 9.4.3.5 is proposed to be changed to add a fourth VAS pressure differential instrument, identified as VAS-033, to provide indication, control, and alarm functions for the auxiliary building component cooling water system (CCS) valve room (Room 12561) while the exhaust flow path is aligned to the VFS filtered exhaust. The auxiliary building CCS valve room is an area of the auxiliary building that is physically remote and separate from the currently monitored and controlled areas.

The proposed change enables pressure differential monitoring and control for the CCS valve room, consistent with changes to the design calculations supporting final design development of the VAS. The existing pressure differential instrument VAS-033 for the auxiliary building middle annulus is proposed to be renumbered as VAS-034. This involves a change to COL Appendix C (and plant-specific DCD Tier 1) Table 2.7.5-1 to add VAS-034 for the auxiliary building as the last row of the table, and to move existing VAS-030 for the fuel handling area to the first row of the table as an editorial change.

Licensing Basis Changes for Addition of Fourth VAS Pressure Differential Instrument The following licensing basis changes are proposed to address the changes to add the fourth VAS pressure differential instrument, numbered as VAS-033, for the auxiliary building CCS valve room and to renumber the existing pressure differential instrument VAS-033 for the auxiliary building middle annulus as VAS-034:

1. COL Appendix C (and plant-specific DCD Tier 1) is revised as follows:

a) Table 2.7.5-1 is revised to add VAS-034 for the auxiliary building as the last row of the table, and to move existing VAS-030 for the fuel handling area to the first row of the table as an editorial change.

2. The UFSAR is revised as follows:

a) Subsection 9.4.3.5 is revised to add VAS-034, and to add the fuel handling area of the auxiliary building to the list of radiologically controlled areas maintained at a negative pressure by the VAS.

Technical Evaluation of Addition of Fourth VAS Pressure Differential Instrument As described in UFSAR Subsection 9.4.3, the VAS provides ventilation for the fuel handling area of the auxiliary building, and the radiologically controlled portions of the auxiliary and annex buildings, except for the health physics and hot machine shop areas, which are provided with a separate ventilation system, the health physics and hot machine shop heating, ventilation, and air-conditioning (HVAC) system (VHS). The VAS consists of the auxiliary/annex building ventilation subsystem and the fuel handling area ventilation subsystem. These subsystems provide ventilation to maintain occupied areas and access and equipment areas within their design temperature range, provide outside air for plant personnel, and prevent the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas, by maintaining a negative pressure differential relative to the outside atmosphere and non-radiologically controlled areas in the areas serviced. As described in UFSAR Subsection 9.4.3.1.2, the VAS automatically isolates selected building areas by closing the supply and exhaust duct isolation dampers and starts the containment air filtration system (VFS) when high airborne radioactivity in the exhaust air duct or high

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 8 of 24 positive pressure differential relative to the outside atmosphere and non-radiologically controlled areas is detected. The VAS has no safety-related function.

The proposed changes add the fourth VAS pressure differential instrument, identified as VAS-033, to provide indication, control, and alarm functions for the auxiliary building CCS valve room, and to renumber the existing pressure differential instrument VAS-033 for the auxiliary building middle annulus as VAS-034. These proposed changes do not adversely affect the design functions of the VAS as described above. The proposed changes enable pressure differential monitoring and control for the auxiliary building CCS valve room, which is an area of the auxiliary building that is physically remote and separate from the currently monitored and controlled areas. This provides prevention of the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas, by maintaining a negative pressure differential for the auxiliary building CCS valve room relative to the outside atmosphere and non-radiologically controlled areas. The changes to COL Appendix C (and plant-specific DCD Tier 1) Table 2.7.5-1 to add VAS-034 for the auxiliary building as the last row of the table, and to move existing VAS-030 for the fuel handling area to the first row of the table as an editorial change, are consistent with these changes.

C. Changes in VAS Fuel Handling Area Ventilation Subsystem and Auxiliary/Annex Building Ventilation Subsystem Ventilation Flow Rates To maintain the required capacity of the VWS high capacity subsystem at the current design values (i.e., maintaining heat loads in the areas serviced below the capability of the VWS 1700-ton water-cooled chiller and 300-ton air-cooled chiller), manufacturers equipment data, rather than previous conservative estimates for heat loads in the areas serviced by the VAS, are used for determining required air conditioning tonnage. These changes are the result of optimizing the VWS high capacity subsystem and VAS electrical power and functional performance requirements, while minimizing changes to the required capacity of the VWS high capacity subsystem. As a result, changes to the required supply and exhaust ventilation flow rates for the VAS are proposed. 2.7.05.02.ii..

The airborne radioactivity concentration calculations for the fuel handling area and the auxiliary building, which form the bases for UFSAR Tables 12.2-25 and 12.2-27, are affected by these design changes to the VAS, and the other changes to input parameters as shown in UFSAR Tables 12.2-24 and 12.2-26. The airborne radioactive concentrations for the fuel handling area were previously calculated using the total exhaust flow and the total air volume of areas serviced by the VAS fuel handling area subsystem. This method of calculating the radioactivity concentration is not conservative. In this proposed change, the parameters and assumptions for the airborne radioactivity concentrations are updated to use only the air outflow rate of the VAS fuel handling area subsystem and the associated air volume. These changes result in small increases in the radionuclide specific maximum airborne radioactivity concentrations.

Licensing Basis Changes for Changes in VAS Fuel Handling Area Ventilation Subsystem and Auxiliary/Annex Building Ventilation Subsystem Ventilation Flow Rates The following licensing basis changes are proposed to address the modifications to the VAS to change the VAS fuel handling area ventilation subsystem and auxiliary/annex building ventilation subsystem nominal design ventilation flow rates, and to address the resulting changes to the inputs and results of the airborne radioactivity concentration calculations:

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 9 of 24

1. COL Appendix C (and plant-specific DCD Tier 1) is revised as follows:

a) Inspections, Tests, Analyses and Acceptance Criteria (ITAAC) Table 2.7.5-2, ITAAC No. 2.7.05.02.ii, is revised to clarify that the rail car bay/solid radwaste system area is included in the scope of the ventilation flow rate test and change the total ventilation flow rate through the auxiliary building fuel handling and rail car bay/solid radwaste system areas to 10,710 cfm.

2. The UFSAR is revised as follows:

a) Subsection 9.1.3.1.4 is revised to delete the activity level in the SFP that is equivalent to exposure rates to personnel on the SFP fuel handling machine of less than 2.5 millirem per hour.

b) Table 9.1-3 (Sheets 1 and 2) are revised to change the SFP demineralizers and SFP filter nominal flow rates to 200 gpm.

c) Subsection 9.4.3.2.1.1 is revised to change the nominal design ventilation flow rate through each of the two supply air handling units of the auxiliary/annex building ventilation subsystem to 14,000 scfm.

d) Subsection 9.4.3.2.1.2 is revised to change the nominal design ventilation flow rate through each of the two supply air handling units of the fuel handling area ventilation subsystem to 4,900 scfm.

e) Table 12.2-24 is revised to change the assumptions used in the calculation of radionuclide specific maximum airborne radioactivity concentration in the fuel handling area as follows:

i.

The nominal design ventilation flow rate through the auxiliary building fuel handling area is changed to 9,500 cfm, with Note 1 revised to state: This flow rate is defined as the sum of the fuel handling area exhaust flow from room 12562 (fuel handling area) and exhaust flow from room 12562 to room 12471 (solid radwaste system valve/piping area).

ii. The fuel handling area free air volume is increased to 225,450 ft3.

iii. Iodine and particulate filter efficiencies are deleted.

iv. The time from shutdown to reactor vessel head removal is reduced to 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months .

v. The SFP purification flow rate is decreased to 150 gpm.

vi. The evaporation rate of SFP water is decreased to 430 lbs/hr.

vii. The partition coefficients for noble gases are freely released, tritium of 1, halogens of 100, and other radionuclides of 1,000 are added.

viii. The spent fuel pool tritium concentration is changed to reactor coolant tritium concentration and increased to 3.5 µCi/g.

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 10 of 24 f) Tier 2 Table 12.2-25 is revised to change the radionuclide specific maximum airborne radioactivity concentrations in the fuel handling area to reflect the current maximum airborne radioactivity calculations. In addition, the footnotes are revised as follows:

i.

Footnote 1 is revised to state that the maximum activity concentration is calculated to occur 50 hours5.787037e-4 days 0.0139 hours 8.267196e-5 weeks 1.9025e-5 months after shutdown in this case.

ii. Footnote 2 is revised as follows:

An editorial change is made to replace that with than so that the note reads less than Reference to 56Mn, 84Br, 85Br, 89Kr, 88Rb, 89Rb, 131Te, 135mXe, 137Xe, 138Xe, 137mBa, and 144Pr are deleted, as these radionuclides are not expected to exist in the auxiliary building fuel handling area.

References to 83Br, 83mKr, 87Kr, 92Sr, 92Y, 129I, and 132I, are deleted, and the appropriate concentrations for Br-83, Kr-83m, Kr-87, Sr-92, Y-92, and I-129, and I-132 are added to the table, as the current calculation determined a concentration greater than 1.0E-20 Ci/cm3 for each of these radionuclides.

Reference to 103mRh is added, and existing references to 91mY, 129Te, 134Te, 134I, and 138Cs are retained, as the current calculation determined a concentration less than 1.0E-20 Ci/cm3 for each of these radionuclides.

g) Tier 2 Table 12.2-26 is revised to change the assumptions used in the calculation of radionuclide specific maximum airborne radioactivity concentrations in the auxiliary building as follows:

i.

The nominal expected ventilation exhaust air flow rate for the VAS auxiliary/annex building ventilation subsystem is increased to 25,320 cfm, which is then reduced by 10% for conservatism in the calculations of the auxiliary building radionuclide specific maximum airborne radioactivity concentrations consistent with Note 2.

ii.

The auxiliary building free air volume is increased to 411,200 ft3.

iii.

The primary coolant leakage to auxiliary building is increased to 296 lbs/day.

iv.

The flashing fraction is revised to add separate flashing fractions for noble gases of 1 and for other gases of 0.1.

v.

Note 1 is revised to state: This flow rate is defined as the sum of the auxiliary/annex building exhaust fan flow minus the annex building exhaust flows from room 40357 (containment access corridor), room 40551 (containment air filtration exhaust room A), and 40552 (containment air filtration exhaust room B).

h) Tier 2 Table 12.2-27 is revised to change the radionuclide specific maximum airborne radioactivity concentrations in the auxiliary building to reflect the current maximum airborne radioactivity calculations.

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Page 11 of 24 Technical Evaluation of Changes in VAS Fuel Handling Area Ventilation Subsystem and Auxiliary/Annex Building Ventilation Subsystem Ventilation Flow Rates As described in UFSAR Subsection 9.4.3, the VAS provides ventilation for the fuel handling area of the auxiliary building, and the radiologically controlled portions of the auxiliary and annex buildings, except for the health physics and hot machine shop areas, which are provided with a separate ventilation system (VHS). The VAS consists of the auxiliary/annex building ventilation subsystem and the fuel handling area ventilation subsystem. These subsystems provide ventilation to maintain occupied areas and access and equipment areas within their design temperature range, provide outside air for plant personnel, and prevent the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas, by maintaining a negative pressure differential relative to the outside atmosphere and non-radiologically controlled areas in the areas serviced. Hot water heating coils supplied with water from the hot water heating system (VYS) and cooling coils supplied with water from the VWS high capacity subsystem are used to maintain ambient room temperatures within the normal range. As described in UFSAR Subsection 9.4.3.1.2, the VAS automatically isolates selected building areas by closing the supply and exhaust duct isolation dampers and starts the containment air filtration system (VFS) when high airborne radioactivity in the exhaust air duct or high positive pressure differential relative to the outside atmosphere and non-radiologically controlled areas is detected. The VAS has no safety-related function.

Fuel Handling Area Airborne Radioactivity Concentration Calculation Input Parameter Changes The VAS design as described in UFSAR Subsection 9.4.3.2.1.2 and UFSAR Table 12.2-24 is proposed to be modified to change the total nominal design ventilation flow rates provided by the fuel handling area ventilation subsystem as a result of the reduction in heat loads in the areas serviced by the VAS. The nominal design ventilation flow rate through each of the two supply air handling units of the fuel handling area ventilation subsystem is decreased to 4,900 scfm. The total nominal design exhaust ventilation flow rate through the auxiliary building fuel handling and rail car bay/solid radwaste system areas is decreased to 11,900 cfm. The nominal design exhaust ventilation flow rate through the fuel handling area is defined as the sum of the fuel handling area exhaust flow from Room 12562 and exhaust flow from Room 12562 to Room 12471, which excludes the rail car bay/solid radwaste system exhaust flow, of 9,500 cfm. This involves a change to the ventilation flow rate in COL Appendix C (and plant-specific DCD Tier 1) ITAAC Table 2.7.5-2, ITAAC No. 2.7.05.02.ii, to 10,710 cfm, which is 90% of the total nominal design ventilation flow rate through the auxiliary building fuel handling and rail car bay/solid radwaste system areas of 11,900 cfm, and which represents the necessary minimum nominal design exhaust ventilation flow rate to maintain the auxiliary building fuel handling area at a negative pressure differential relative to the outside atmosphere and non-radiologically controlled areas. This is consistent with the existing margin in the current licensing basis. Additionally, the description of the test required by ITAAC Table 2.7.5-2, ITAAC No. 2.7.05.02.ii is revised to clarify that the ventilation flow rate test measures flow through the rail car bay/solid radwaste system area, as well as the currently required fuel handling area, to conform with the UFSAR Subsection 9.4.3.2.1.2 description of the plant areas served by the VAS fuel handling area subsystem.

As described in UFSAR Subsection 9.4.3.2.1.2, the fuel handling area ventilation subsystem serves the fuel handling area, rail car bay/filter storage, and other plant areas in which fuel and radioactive waste are stored or transferred. The supply air handling units discharge into

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Page 12 of 24 a ducted supply distribution system, which is routed to the fuel handling and rail car bay/filter storage areas of the auxiliary building. Therefore, inclusion of the rail car bay/solid radwaste system area in the scope of this ITAAC ventilation flow rate test is consistent with the subsystem design, as described in UFSAR Subsection 9.4.3.2.1.2, and provides a more comprehensive description of the test performed to verify the ability of the VAS to maintain the areas served by this subsystem at a slightly negative pressure relative to the atmosphere or adjacent clean plant areas.

The proposed modifications to reduce the VAS fuel handling area ventilation subsystem total nominal design ventilation flow rate through the auxiliary building fuel handling and rail car bay/solid radwaste system areas to 11,900 cfm does not adversely affect the design functions of the VAS to maintain occupied areas and access and equipment areas within their design temperature range, and to provide outside air for plant personnel. The change in nominal design ventilation flow rate through each of the two supply air handling units of the fuel handling area ventilation subsystem to 4,900 scfm continues to maintain environmental conditions that support worker efficiency during fuel handling operations. The design condition of 90°F dry bulb/75°F wet bulb satisfies the maximum wet bulb globe temperature of 80°F (96°F dry bulb) as described in UFSAR Subsection 9.4.3.2.1.2. The capability of the supply and exhaust duct isolation dampers to close when high airborne radioactivity in the exhaust air or high positive pressure differential relative to the outside atmosphere and non-radiologically controlled areas is detected is not affected. The change to the total ventilation flow provided through the auxiliary building fuel handling and rail car bay/solid radwaste system areas in COL Appendix C (and plant-specific DCD Tier 1) ITAAC Table 2.7.5-2, ITAAC No. 2.7.05.02.ii, to 10,710 cfm is consistent with the previously certified value identified as 90% of the nominal design ventilation flow rate through the auxiliary building fuel handling and rail car bay/solid radwaste system areas. The fuel handling area airborne radioactivity concentration calculation uses an assumed ventilation flow rate of 90% of the nominal design flow rate of 9,500 cfm, which results in a conservative calculated airborne radioactivity concentration in the fuel handling area that remains acceptable.

During design finalization, the sum of changes to SFS line routing, tee losses, as well as verification of pump inputs and piping, result in changes to the required SFS pump design point (i.e., increases the required total head versus flow rate). Based on this change to the SFS pump design point, the SFS nominal design purification flow rate is proposed to be lowered from 250 to 200 gpm to reduce the required pump discharge head. The proposed changes maintain the SFS design functions without requiring a change to SFS pump design requirements. In addition, an SFS nominal design purification flow rate of 200 gpm provides greater than one water turnover in 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , and greater than one water turnover per day of the SFP and fuel transfer canal. Operation of both SFS trains results in three water turnovers in 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months (assuming no water displacement for fuel). This water turnover rate, and resulting SFS nominal design purification flow rate through the SFS filters and demineralizers, is similar to existing operating plants (approximately 100 gpm). This flow rate provides ample purification to both maintain acceptable dose rates in the spent fuel pool and fuel transfer canal areas, and to provide acceptable water clarity to permit necessary operations in these areas, based on the comparison of system performance to existing operating plants. The proposed changes to use a lower 150 gpm SFS purification flow rate in determining radionuclide specific maximum airborne radioactivity concentrations in the fuel handling area is conservative, and has no adverse effect on the results of the calculation which remain acceptable. The proposed changes to delete the activity level in

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Page 13 of 24 the SFP that is equivalent to exposure rates to personnel on the SFP fuel handling machine of less than 2.5 millirem per hour in UFSAR Subsection 9.1.3.1.4 removes nonessential information. Using the primary design criteria that exposure rates do not exceed 2.5 millirem per hour is sufficient to ensure that occupational radiation exposure is maintained at levels that support as low as reasonably achievable (ALARA) goals.

For the airborne radioactivity concentration calculations for the fuel handling area, the proposed changes to the input assumptions in UFSAR Table 12.2-24 include the following:

1. The total nominal design exhaust ventilation flow rate through the fuel handling area (room 12562) is decreased to 9,500 cfm. This reflects the fuel handling area exhaust flow from room 12562 and exhaust flow from room 12562 to room 12471 (solid radwaste system valve/piping area).

2. Iodine and particulate filter efficiencies are deleted, as there is no filtration in the recirculation flowpath for the fuel handling area. Therefore, filtration is not relevant and not used in the calculation of the airborne radioactivity concentrations in the fuel handling area.

3. The fuel handling area free air volume used in determining airborne radioactivity concentrations is increased to 225,450 ft3. This change is the result of calculations completed during design finalization activities using final as-designed structural information for the auxiliary building.

4. The revised airborne radioactivity concentration calculations for the fuel handling area also include reducing the time from shutdown to removal of the reactor vessel head to 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months , and an increase of the assumed reactor coolant tritium concentration to 3.5 µCi/g. The airborne isotopic concentrations for the fuel handling area provided in UFSAR Table 12.2-25 are based on the assumption described in Footnote 1 to the table, which states that the maximum activity concentration is calculated to occur 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months after removal of the head, or 102 hours0.00118 days 0.0283 hours 1.686508e-4 weeks 3.8811e-5 months after shutdown in this case. However, COL Appendix A Technical Specification 3.9.5, Decay Time, allows movement of irradiated fuel assemblies in the reactor pressure vessel after the reactor is subcritical for at least 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months for radioactive decay time. Therefore, the airborne radioactivity concentration calculation for the fuel handling area is revised to include this change in input assumption from 102 hours0.00118 days 0.0283 hours 1.686508e-4 weeks 3.8811e-5 months after shutdown to 50 hours5.787037e-4 days 0.0139 hours 8.267196e-5 weeks 1.9025e-5 months after shutdown, which results in the need to revise UFSAR Table 12.2-25. The revised airborne radioactivity concentration calculation for the fuel handling area determined that there are radionuclides currently specified in Footnote 2 of the table that are not expected to exist in the auxiliary building fuel handling area, or that have maximum airborne radioactivity concentrations exceeding the threshold of 1.0E-20 Ci/cm3, which should be deleted from the footnote. In addition, radionuclide 103mRh is added to Footnote 2 as the maximum airborne radioactivity concentration is less than the threshold of 1.0E-20 Ci/cm3.

5. A conservative SFS purification flow rate of 150 gpm is used in the calculation of the airborne radioactivity concentrations in the fuel handling area.

6. Based on the revised ventilation nominal design flow rates, the evaporation rate from the SFP is reduced to 430 lbs/hr during refueling, which is the plant mode for which the maximum airborne radioactivity concentrations are calculated. This change is the result of calculations completed during design finalization activities based on the proposed

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Page 14 of 24 design change decreasing the total ventilation air flow provided through the fuel handling area ventilation subsystem and the increase in the fuel handling area free air volume.

7. The partition coefficients for noble gases of freely released, tritium of 1, halogens of 100, and other radionuclides of 1,000 are added to reflect these significant inputs to the airborne radioactivity concentration calculations for the fuel handling area.

8. Spent fuel pool tritium concentration is changed to reactor coolant tritium concentration, as this reflects the bounding tritium concentration during refueling used in the calculation of the airborne radioactivity concentrations in the fuel handling area.

The fuel handling area ventilation subsystem nominal design ventilation flow rate with the proposed changes continues to dilute potential airborne contamination to maintain the concentration at the site boundary within 10 CFR Part 20 allowable effluent concentration limits and the internal room airborne radioactivity concentrations within 10 CFR 20 occupational Derived Airborne Concentration (DAC) limits during normal plant operation.

The overall effect of the various design and input changes proposed in this request that affect the calculation for evaluating maximum airborne radioactivity concentrations in the fuel handling area during normal operations is minimal. General design considerations and methods to maintain in-plant radiation exposures ALARA consistent with the recommendations of Regulatory Guide 8.8 includes minimizing radiation levels in routinely occupied plant areas in the vicinity of plant equipment expected to require personnel attention. The proposed changes do not adversely impact this objective, as the design of the VAS still maintains the design functions, including maintaining a ventilation air flow pattern from areas of lower radioactivity to areas of higher radioactivity to prevent releases of radioactive materials to non-radioactive areas, and the resulting maximum airborne radioactivity concentrations for the fuel handling area are maintained at an acceptable level with each a maximum DAC fraction of less than 7.72E-01. There are no radiation zone changes required because of these proposed changes, and there are no changes required to the existing radiation protection controls that preclude a significant increase in occupational radiation exposure as required by 10 CFR Part 20.

The additional change made to the calculation of airborne radioactivity concentrations in the fuel handling area to assume that removal of the reactor vessel head occurs 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months after shutdown for the case presented in UFSAR Table 12.2-25 is consistent with COL Appendix A Technical Specifications 3.9.5, Decay Time, which allows movement of irradiated fuel assemblies in the reactor pressure vessel after the reactor is subcritical for at least 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months for radioactive decay time. Therefore, this change is consistent with the procedures for refueling operations based on COL Appendix A Technical Specifications 3.9.5.

These changes made to the calculation of airborne radioactivity concentrations in the fuel handling area for the case presented in UFSAR Table 12.2-25 are changes to input parameters based on plant-specific considerations and are not intrinsic to the methodology, and these revised input parameters do not exceed the range of applicability for the methodology. Therefore, as defined in NEI 96-07, these input parameters are not considered a part of the methodology, and the proposed changes do not represent an adverse change to a method of evaluation or use of an alternate method of evaluation from that described in the plant-specific DCD, or UFSAR that is used in establishing design bases or in the safety analysis.

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Page 15 of 24 Auxiliary Building Airborne Radioactivity Concentration Calculation Input Parameter Changes The VAS design as described in UFSAR Subsection 9.4.3.2.1.1 and UFSAR Table 12.2-26 is proposed to be modified to change the total nominal design ventilation flow rates provided by the auxiliary/annex building ventilation subsystem as a result of the reduction in heat loads in the areas serviced by the VAS. The nominal design ventilation flow rate through each of the two supply air handling units of the auxiliary/annex building ventilation subsystem is decreased to 14,000 scfm. This also results in an increase in total nominal design ventilation exhaust flow rate for the auxiliary/annex building subsystem and an increase in the assumed total ventilation exhaust flow rate shown in UFSAR Table 12.2-26 to 25,320 cfm, which reflects the auxiliary/annex building exhaust fan flow minus the annex building exhaust flows from room 40357 (containment access corridor), room 40551 (containment air filtration exhaust room A), and 40552 (containment air filtration exhaust room B).

For the airborne radioactivity concentration calculations for the auxiliary building, the proposed changes to the input assumptions in UFSAR Table 12.2-26 include the following:

1. The total nominal design ventilation exhaust flow rate for the auxiliary building is increased to 25,320 cfm. This reflects the auxiliary/annex building exhaust fan flow minus the annex building exhaust flows from room 40357 (containment access corridor),

room 40551 (containment air filtration exhaust room A), and 40552 (containment air filtration exhaust room B).

2. The auxiliary building free air volume is increased to 411,200 ft3. This change is the result of calculations completed during design finalization activities using final as-designed structural information for the auxiliary building.

3. The assumed primary coolant leakage to the auxiliary building is increased to 296 lbs/day. This change is the result of calculations completed during design finalization activities using final as-designed piping systems that may contain reactor coolant in the auxiliary building, and accounts for pump, valve, and sampling leakage.

4. The assumed flashing fractions for noble gases of 1 and for other gases of 0.1 are added based on Appendix A, Section 5, of Regulatory Guide 1.183.

The auxiliary/annex building ventilation subsystem nominal design ventilation flow rate with the proposed changes continues to dilute potential airborne contamination to maintain the concentration at the site boundary within 10 CFR Part 20 allowable effluent concentration limits and the internal room airborne radioactivity concentrations within 10 CFR Part 20 occupational DAC limits during normal plant operation. The overall effect of the various design and input changes proposed in this request that affect the calculation for evaluating maximum airborne radioactivity concentrations in the auxiliary building during normal operations is minimal. General design considerations and methods to maintain in-plant radiation exposures ALARA consistent with the recommendations of Regulatory Guide 8.8 includes minimizing radiation levels in routinely occupied plant areas in the vicinity of plant equipment expected to require personnel attention. The proposed changes do not adversely impact this objective, as the design of the VAS still maintains the design functions including maintaining a ventilation air flow pattern from areas of lower radioactivity to areas of higher radioactivity to prevent releases of radioactive materials to non-radioactive areas, and the resulting maximum airborne radioactivity concentrations for the auxiliary building are maintained at an acceptable level with a maximum DAC fraction of less than 7.28E-01.

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Page 16 of 24 There are no radiation zone changes required because of these proposed changes, and there are no changes required to the existing radiation protection controls that preclude a significant increase in occupational radiation exposure as required by 10 CFR Part 20.

These changes made to the calculation of airborne radioactivity concentrations in the auxiliary building for the case presented in UFSAR Table 12.2-27 are changes to input parameters based on plant-specific considerations and are not intrinsic to the methodology, and these revised input parameters do not exceed the range of applicability for the methodology. Therefore, as defined in NEI 96-07, these input parameters are not considered a part of the methodology. Therefore, the proposed changes do not represent an adverse change to a method of evaluation or use of an alternate method of evaluation from that described in the plant-specific DCD, or UFSAR that is used in establishing design bases or in the safety analysis.

Summary of Radiologic Impact of Changes to Airborne Radioactivity Concentration Calculations UFSAR Section 12.2 describes the sources of radiation that form the basis for shielding design calculations and the sources of airborne radioactivity used for the design of personnel protection measures and dose assessment. The maximum airborne radioactivity values during plant operations are evaluated to determine radiological impacts where personnel occupancy is expected.

As described in UFSAR Subsection 12.2.2.2, the source of airborne radioactivity in the fuel handling area is leakage from stored spent fuel assemblies and the evaporation losses from the SFP. The fuel handling area ventilation subsystem constantly removes activity and discharges it to the plant vent. The maximum airborne radioactivity concentrations in the fuel handling area are calculated using the assumptions and parameters in UFSAR Table 12.2-24. The maximum airborne radioactivity values during plant operations are evaluated to determine radiological impacts where personnel occupancy is expected. The resulting airborne isotopic concentrations are provided in UFSAR Table 12.2-25.

As described in UFSAR Subsection 12.2.2.3, the source of airborne activity in the auxiliary building atmosphere is primarily equipment leakage. The auxiliary/annex building ventilation subsystem constantly removes activity and discharges it to the plant vent. The maximum airborne concentration in the auxiliary building is calculated using the assumptions and parameters in UFSAR Table 12.2-26. The resulting airborne isotopic concentrations are provided in UFSAR Table 12.2-27.

As described in UFSAR Subsection 12.3.3.2, the design criteria for the plant HVAC systems include the following:

1. During normal operation, the average and maximum airborne radioactivity levels to which plant personnel are exposed in restricted areas of the plant are ALARA and within the limits specified in 10 CFR Part 20. The average and maximum airborne radioactivity levels in unrestricted areas of the plant during normal operation, are ALARA and within the limits of 10 CFR Part 20.

2. During normal operation, the dose from concentrations of airborne radioactive material in unrestricted areas beyond the site boundary is ALARA and within the limits specified in 10 CFR Part 20 and 10 CFR Part 50, Appendix I.

The airborne radioactivity concentration calculations for the auxiliary building, including the fuel handling area, which form the bases for UFSAR Tables 12.2-25 and 12.2-27, are

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Page 17 of 24 affected by these design changes to the VAS, and the other changes to input parameters described, including the decrease in the SFS nominal design purification flow rate. These design and input parameter changes result in small increases to the radionuclide specific maximum airborne radioactivity values calculated for the auxiliary building, including the fuel handling area, and changes to the activity level in the SFP, but only increase maximum radionuclide specific airborne radioactivity concentrations in the auxiliary building, including the fuel handling area, by a small fraction as described previously.

Technical Evaluation of Other Impacts An impact review determined that these proposed changes do not affect or require any change to the AP1000 PRA presented in UFSAR Chapter 19, including the Fire PRA, results and insights (e.g., core damage frequency (CDF) and large release frequency (LRF)). There are no existing failures of the VCS or VAS included in the PRA model, and no new postulated failures of the VCS or VAS are required in the PRA model. Therefore, there are no changes required to initiating event frequencies and system logic models of the PRA.

The existing PRA risk significance investment protection determination for VCS and VAS is not affected. The systems, structures, and components (SSCs) affected by these proposed changes are not identified as risk-significant within the scope of the Design Reliability Assurance Program (D-RAP) in UFSAR Table 17.4-1.

No fire area changes are required because of these proposed changes. No combustible materials are added by the proposed changes, and no fire area boundaries are changed.

The affected VCS and VAS SSCs are not modified such that fire barriers, including walls, floors, or other structures, and fire dampers for the associated ventilation systems, are changed.

There are no radiation zone changes required because of these proposed changes. The changes to VCS and VAS SSCs do not introduce new or different amounts or types of radioactive materials, nor do they involve changes to radiation zone boundaries, including walls, floors, or other structures that provide shielding features. The proposed modifications to the VAS fuel handling area ventilation subsystem and auxiliary/annex building ventilation subsystem nominal design ventilation flow rates do not adversely affect the calculated airborne radioactivity concentrations in the fuel handling area and auxiliary building, which conservatively use a 10% lower ventilation flow rate than the expected nominal design ventilation flow rate. Therefore, there are no changes required to the existing radiation protection controls that preclude a significant increase in occupational radiation exposure as required by 10 CFR Part 20.

The proposed changes do not affect the containment, control, channeling, monitoring, processing or releasing of radioactive or non-radioactive materials. The proposed changes to the VCS to modify the configuration of the containment recirculation fan coil unit assemblies, and to revise nominal design values for the containment recirculation fan coil unit assemblies cooling and heating requirements, do not adversely affect the containment and control of radioactive and non-radioactive materials inside containment, nor do they adversely affect the containment boundary. The proposed changes to add the fourth VAS pressure differential instrument, numbered as VAS-033, providing indication, control, and alarm functions for the auxiliary building CCS valve room, and to renumber the existing pressure differential instrument VAS-033 for the auxiliary building middle annulus as VAS-034, do not adversely affect the design functions of the VAS to prevent the

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Page 18 of 24 unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas, by maintaining a negative pressure differential relative to the outside atmosphere and non-radiologically controlled areas in the areas serviced. The proposed modifications to the VAS fuel handling area ventilation subsystem and auxiliary/annex building ventilation subsystem nominal design ventilation flow rates do not adversely affect the capability of the supply and exhaust duct isolation dampers to close when high airborne radioactivity in the exhaust air or high positive pressure differential relative to the outside atmosphere and non-radiologically controlled areas is detected. Accordingly, no effluent release path is affected.

In addition, the types and quantities of expected effluents are not changed by the proposed changes. Therefore, the proposed change does not affect radioactive or non-radioactive material effluents.

Summary The proposed changes to revise UFSAR information, and involved changes to COL Appendix C (and plant-specific DCD Tier 1) information concerning detailed design of the VCS and VAS do not adversely affect the design functions of the VCS or VAS.

The proposed changes for the VCS address changes in total required design air flow rates and total design cooling and heating requirements as a result of the final design of the VCS. These proposed changes are acceptable because the design functions of the VCS to control air temperature and reduce humidity in the containment, thereby providing a suitable environment for equipment operability during normal power operation and for personnel accessibility and equipment operability during refueling and shutdown, continue to be met.

The proposed change to add the fourth VAS pressure differential instrument, numbered as VAS-033, enables pressure differential indication, control, and alarm functions for the auxiliary building CCS valve room, which is an area of the auxiliary building that is physically remote and separate from the currently monitored and controlled areas. This proposed change is acceptable because the design function of the VAS to prevent the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas by maintaining a negative pressure differential in radiologically controlled areas relative to the outside atmosphere and non-radiologically controlled areas continues to be met.

The proposed changes to reduce the VAS fuel handling area ventilation subsystem and auxiliary/annex building ventilation subsystem nominal design ventilation flow rates continue to provide adequate ventilation for the auxiliary building, including the fuel handling area. These proposed changes are acceptable because the design functions of the VAS to maintain occupied areas and access and equipment areas within their design temperature range, and to provide outside air for plant personnel, continue to be met. This includes the VAS fuel handling area ventilation subsystem remaining capable of maintaining environmental conditions that support worker efficiency during fuel handling operations as described in UFSAR Subsection 9.4.3.2.1.2. In addition, the capability of the supply and exhaust duct isolation dampers to close when high airborne radioactivity in the exhaust air or high positive pressure differential relative to the outside atmosphere and non-radiologically controlled areas is detected is not affected.

The proposed changes do not adversely affect any safety-related equipment or function, design function, radioactive material barrier, or safety analysis. Additionally, the change activity has no adverse impact on the emergency plan or the physical security plan implementation, because there are no changes to physical access to credited equipment inside the Nuclear Island

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Page 19 of 24 (including containment or the auxiliary building) and no adverse impact to plant personnels ability to respond to any plant operations or security event.

3. TECHNICAL EVALUATION (Included in Section 2)

4. REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 10 CFR 52.98(f) requires NRC approval for any modification to, addition to, or deletion from the terms and conditions of a Combined License (COL). The proposed changes involve a change to COL Appendix C Inspections, Tests, Analyses and Acceptance Criteria (ITAAC) information, with corresponding changes to the associated plant specific Design Control Document (DCD) Tier 1 information. Therefore, NRC approval is required prior to making the plant specific proposed changes in this license amendment request.

10 CFR Part 52, Appendix D, Section VIII.B.5.a allows an applicant or licensee who references this appendix to depart from Tier 2 information, without prior NRC approval, unless the proposed departure involves a change to, or departure from, Tier 1 information, Tier 2* information, or the Technical Specifications, or requires a license amendment under paragraphs B.5.b or B.5.c of the section. The proposed changes for the VCS, which include changes to UFSAR Subsections 1.2.4.1, 9.4.6.2.1, 9.4.6.2.2, and 9.4.6.2.3; UFSAR Figure 9.2.7-1 (Sheet 3); UFSAR Table 9.4.6-1; and UFSAR Figure 9.4.6-1, involve a revision to COL Appendix C (and plant-specific DCD Tier 1) Table 2.7.7-3 information. The proposed changes for the VAS, which include changes to UFSAR Subsection 9.4.3.5, involve a revision to COL Appendix C (and plant-specific DCD Tier 1) Table 2.7.5-1 information. The proposed changes for the VAS, which include changes to UFSAR Subsection 9.4.3.2.1.2 and UFSAR Table 12.2-24, involve a revision to COL Appendix C (and plant-specific DCD Tier 1) ITAAC Table 2.7.5-2, ITAAC No. 2.7.05.02.ii, information. Therefore, NRC approval is required for the Tier 2 and involved Tier 1 departures.

10 CFR Part 50, Appendix A, General Design Criterion (GDC) 2 requires that structures, systems and components important to safety be designed to withstand the effects of natural phenomena, such as earthquakes. The proposed changes to the VCS are designed to the existing requirements requiring system equipment and ductwork whose failure could affect the operability of safety-related systems or components to be designed to seismic Category II requirements, while the remaining portion of the system remains non-seismic.

The proposed changes to the VAS to provide additional pressure differential monitoring and control are designed to the existing seismic design requirements. The proposed changes to the required VAS supply air flow rate and total ventilation flow provided through the auxiliary building fuel handling area do not involve physical modifications or addition of systems, structures, and components, and do not impact the existing seismic design requirements.

Therefore, the proposed changes comply with the requirements of GDC 2.

10 CFR Part 50, Appendix A, GDC 4 requires that systems structures and components can withstand the dynamic effects associated with missiles, pipe whipping, and discharging fluids, excluding dynamic effects associated with pipe ruptures, the probability of which is

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Page 20 of 24 extremely low under conditions consistent with the design basis for the piping. The proposed changes to the VCS and VAS do not adversely affect the configuration of the walls and floors that provide separation between sources and potential targets. The proposed changes have no effect on the capability of the systems, structures, and components to withstand dynamic effects associated with missiles, pipe whipping, and discharging fluids as required by this criterion. The proposed changes do not change the requirements for anchoring safety-related components and supports to seismic Category I structures. Therefore, the proposed changes comply with the requirements of GDC 4.

10 CFR Part 50, Appendix A, GDC 17 requires that an onsite electric power system and an offsite electric power system be provided to permit functioning of structures, systems, and components important to safety. The proposed changes to the VCS and VAS are within the capability of the existing onsite electric power system and offsite electric power system. For the change that reconfigures the containment recirculation fan coil unit assemblies, the electrical load requirements are considered in the sizing of the onsite standby diesel generators and offsite electric power system. The proposed change to the VAS to provide additional pressure differential monitoring and control does not impact the electric power systems. The proposed changes to the required VAS supply air flow rate and total ventilation flow provided through the auxiliary building fuel handling area result in a change in electrical load requirements, but are also considered in the sizing of the onsite standby diesel generators and offsite electric power system. Therefore, the proposed changes comply with the requirements of GDC 17.

10 CFR Part 50, Appendix A, GDC 60 requires that there be provisions for controlling the release of radioactive materials in gaseous and liquid effluents and to handle solid radioactive wastes. The proposed change to the VAS to provide additional pressure differential monitoring and control prevents the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas by maintaining a negative pressure differential in this additional area. The proposed changes to the required VAS supply air flow rate and total ventilation flow provided through the auxiliary building fuel handling area do not affect the isolation of the fuel handling area upon detection of high airborne radioactivity. The other proposed changes do not involve systems, structures, and components that are used to control the release of radioactive materials in gaseous and liquid effluents and to handle solid radioactive wastes. Therefore, the proposed changes comply with the requirements of GDC 60.

10 CFR Part 50, Appendix A, GDC 61 requires that fuel storage and handling, radioactive waste, and other systems which may contain radioactivity be designed to assure adequate safety under normal and postulated accident conditions. The proposed changes to the VCS do not affect the in-plant radiation exposures for personnel inside containment, and do not affect the consequences of any postulated accident. The proposed change to the VAS to provide additional pressure differential monitoring and control to prevent the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas by maintaining a negative pressure differential in this additional area do not affect the consequences of any postulated accident. The proposed changes to the required VAS supply air flow rate and total ventilation flow provided through the auxiliary building fuel handling area do not affect the isolation of the fuel handling area upon detection of high airborne radioactivity, and do not affect the consequences of any postulated accident. Therefore, the proposed changes comply with the requirements of GDC 61.

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 21 of 24 4.2 Precedent No precedent is identified.

4.3 Significant Hazards Consideration Determination The proposed changes would revise the Combined License (COL) in regards to detailed design of the containment recirculation cooling system (VCS) and radiologically controlled area ventilation system (VAS). The requested amendment requires changes to Updated Final Safety Analysis Report (UFSAR) Tier 2 information, which involve changes to COL Appendix C (and plant-specific DCD Tier 1) information.

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

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

Response: No The design functions of the containment recirculation cooling system (VCS) include control of the air temperature and reduction of humidity in the containment to provide a suitable environment for equipment operability during normal power operation, and for personnel accessibility and equipment operability during refueling and shutdown. The proposed changes for the VCS address changes in total required design air flow rates and total design cooling and heating requirements, thereby maintaining these design functions.

The design functions of the radiologically controlled area ventilation system (VAS) include prevention of the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas, by maintaining a negative pressure differential in radiologically controlled areas of the auxiliary building, maintaining occupied areas and access and equipment areas within their design temperature range, and providing outside air for plant personnel. The proposed changes for the VAS enable pressure differential monitoring and control for an area of the auxiliary building that is physically remote and separate from the currently monitored and controlled areas, and provide VAS supply air flow rate and total ventilation flow through the auxiliary building fuel handling area required to maintain occupied areas and access and equipment areas within their design temperature range and to provide outside air for plant personnel, maintaining these design functions.

The proposed changes do not affect the operation of any systems or equipment that initiate an analyzed accident or alter any structure, system, or component (SSC) accident initiator or initiating sequence of events. There are no inadvertent operations or failures of the VCS or VAS considered as accident initiators or part of an initiating sequence of events for an accident previously evaluated.

Therefore, the probabilities of the accidents previously evaluated in the UFSAR are not affected.

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 22 of 24 These proposed changes to the VCS and VAS design as described in the current licensing basis do not have an adverse effect on any of the design functions of the systems. The proposed changes do not affect the support, design, or operation of mechanical and fluid systems required to mitigate the consequences of an accident. There is no change to plant systems or the response of systems to postulated accident conditions. There is no change to the predicted radioactive releases due to postulated accident conditions. The plant response to previously evaluated accidents or external events is not adversely affected, nor do the proposed changes create any new accident precursors. The proposed changes do not affect the prevention and mitigation of other abnormal events, e.g.,

anticipated operational occurrences, earthquakes, floods and turbine missiles, or their safety or design analyses. Therefore, the consequences of the accidents evaluated in the UFSAR are not affected.

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

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

Response: No The proposed changes do not affect the operation of any systems or equipment that may initiate a new or different kind of accident, or alter any SSC such that a new accident initiator or initiating sequence of events is created. The proposed changes revise the VCS and VAS design as described in the current licensing basis to enable the systems to perform required design functions. These proposed changes do not adversely affect any other SSC design functions or methods of operation in a manner that results in a new failure mode, malfunction, or sequence of events that affect safety-related or nonsafety-related equipment.

Therefore, this activity does not allow for a new fission product release path, result in a new fission product barrier failure mode, or create a new sequence of events resulting in significant fuel cladding failures.

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

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

Response: No The proposed changes maintain existing safety margins. The proposed changes to the VCS and VAS do not affect any safety-related design function. These changes do not adversely affect any design code, function, design analysis, safety analysis input or result, or design/safety margin. No safety analysis or design basis acceptance limit/criterion is challenged or exceeded by the proposed changes, and no margin of safety is reduced.

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

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 23 of 24 Based on the above, it is concluded that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of no significant hazards consideration is justified.

4.4 Conclusions Based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public. Therefore, it is concluded that the requested amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of no significant hazards consideration is justified.

5. ENVIRONMENTAL CONSIDERATIONS The proposed changes affect the Combined License (COL) concerning the design of the containment recirculation cooling system (VCS) and radiologically controlled area ventilation system (VAS). The requested amendment requires changes to Updated Final Safety Analysis Report (UFSAR) Tier 2 information, which involve changes to COL Appendix C information, and corresponding changes to the associated plant-specific Design Control Document (DCD) Tier 1 information.

A review has determined that the requested amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR Part 20, or would change an inspection or surveillance requirement. However, facility construction and operation following implementation of the requested amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or a significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the requested amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9), in that:

(i) There is no significant hazards consideration.

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

ND-17-1499 Revised Request for License Amendment: Ventilation System Changes (LAR-16-030R1)

Page 24 of 24 (ii) There is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite.

The proposed changes are unrelated to any aspect of plant construction or operation that would introduce any change to effluent types (e.g., effluents containing chemicals or biocides, sanitary system effluents, and other effluents), or affect any plant radiological or non-radiological effluent release quantities. Furthermore, the proposed changes do not affect any effluent release path or diminish the design functions or operational features credited with controlling the release of effluents during plant operation.

Therefore, the requested amendment does not involve a significant change in the types or a significant increase in the amounts of any effluents that may be released offsite.

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

The proposed changes do not adversely affect walls, floors, or other structures that provide shielding. Plant radiation zones are not affected, and there are no changes required to the existing radiation protection controls that preclude a significant increase in occupational radiation exposure as required by 10 CFR Part 20. Therefore, the requested amendment does not involve a significant increase in individual or cumulative occupational radiation exposure.

Based on the above review of the requested amendment, it has been determined that anticipated construction and operational impacts of the requested amendment do not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in the individual or cumulative occupational radiation exposure.

Accordingly, the requested amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the requested amendment and proposed exemption.

6. REFERENCES None.

Southern Nuclear Operating Company ND-17-1499 Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Exemption Request:

Ventilation System Changes (LAR-16-030R1)

(This Enclosure consists of 10 pages, including this cover page.)

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 2 of 10 1.0 PURPOSE Southern Nuclear Operating Company (the Licensee) requests a permanent exemption from the provisions of 10 CFR 52, Appendix D, Section III.B, Design Certification Rule for the AP1000 Design, Scope and Contents, to allow a departure from elements of the certification information in Tier 1 of the generic AP1000 Design Control Document (DCD). The regulation, 10 CFR 52, Appendix D, Section III.B, requires an applicant or licensee referencing Appendix D to 10 CFR Part 52 to incorporate by reference and comply with the requirements of Appendix D, including certified information in DCD Tier 1. Tier 1 includes Inspections, Tests, Analyses and Acceptance Criteria (ITAAC) that must be satisfactorily performed prior to fuel load. The design details to be verified by these ITAAC are specified in the tables that are referenced in each individual ITAAC.

The Tier 1 information for which a plant-specific departure and exemption is being requested includes detailed information presented in the ITAAC table and supporting tables for the system-based ITAAC related to the containment recirculation cooling system (VCS) and radiologically controlled area ventilation system (VAS).

This request for exemption will apply the requirements of 10 CFR 52, Appendix D, Section VIII.A.4 to allow changes to Tier 1 information due to the following proposed Tier 1 ITAAC changes:

Tier 1 Table 2.7.7-3 is revised to add the two new containment recirculation fan coil unit assemblies (VCS-MS-01C and VCS-MS-01D).

Tier 1 Table 2.7.5-1 is revised to add auxiliary building pressure differential indicator, VAS-034, as the last row of the table and to move existing VAS-030 for the fuel handling area to the first row of the table as an editorial change.

Tier 1 Table 2.7.5-2, Item 2.ii, is revised to change the Acceptance Criterion for the total ventilation flow rate through the auxiliary building fuel handling and rail car bay/solid radwaste system areas to 10,300 cfm.

This request applies the requirements for granting exemptions from design certification information, as specified in 10 CFR Part 52, Appendix D, Section VIII.A.4, 10 CFR 52.63, §52.7, and §50.12.

2.0 BACKGROUND

The Licensee is the holder of Combined License Nos. NPF-91 and NPF-92, which authorize construction and operation of two Westinghouse Electric Company AP1000 nuclear plants, named Vogtle Electric Generating Plant (VEGP) Units 3 and 4, respectively.

The design of the VCS as described in Revision 19 of the AP1000 Design Control Document (DCD) was based upon the approved design of the VCS for the Westinghouse AP600 plant. However, final design of the VCS has resulted in proposed changes to the layout and sizing of the containment recirculation fan coil unit assemblies and associated ductwork, and changes to the total required design air flow rates and total design cooling and heating requirements. This includes proposed changes to the nominal design values for normal and low speed air flow rates, cooling capacity, chilled

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 3 of 10 water flow rate, heating capacity, hot water flow rate, and supply air temperature for normal power operation for the containment recirculation fan coil unit assemblies. This activity involves an exemption from generic DCD Tier 1 Table 2.7.7-3 by adding the two new containment recirculation fan coil unit assemblies (VCS-MS-01C and VCS-MS-01D) to the list of VCS components and locations currently identified in this table.

The VAS provides ventilation for the fuel handling area of the auxiliary building, and the radiologically controlled portions of the auxiliary and annex buildings, with the exception of the health physics and hot machine shop areas, which are provided with a separate ventilation system. The VAS consists of the auxiliary/annex building ventilation subsystem and the fuel handling area ventilation subsystem. These subsystems provide ventilation to maintain occupied areas and access and equipment areas within their design temperature range, provide outside air for plant personnel, and prevent the unmonitored release of airborne radioactivity to the atmosphere or adjacent plant areas, by maintaining a negative pressure differential relative to the outside atmosphere and non-radiologically controlled areas in the areas serviced. The VAS automatically isolates selected building areas by closing the supply and exhaust duct isolation dampers and starts the containment air filtration system (VFS) when high airborne radioactivity in the exhaust air duct or high positive pressure differential relative to the outside atmosphere and non-radiologically controlled areas is detected. Pressure differential indication and alarms are currently provided via three instruments to control the negative pressure in the fuel handling area of the auxiliary building and in the radiologically controlled areas of the auxiliary and annex buildings.

A change is proposed to add a fourth VAS pressure differential instrument to provide indication, control, and alarm functions for the auxiliary building component cooling water system (CCS) valve room while the exhaust flow path is aligned to the VFS filtered exhaust. This provides pressure differential monitoring and control for the auxiliary building CCS valve room, which is an area of the auxiliary building that is physically remote and separate from the currently monitored and controlled areas. An existing pressure differential instrument for the auxiliary building middle annulus is also renumbered as part of this change. This activity involves an exemption from generic DCD Tier 1 Table 2.7.5-1 by adding the new pressure differential instrument to the table and revising the order of the instruments in the table, such that they are listed in numeric order.

Based on final calculations of heat loads in the areas serviced by the VAS, the required cooling airflows for the VAS are changed. This results in proposed changes to the required VAS supply air flow rate and total ventilation flow provided through the auxiliary building fuel handling area. This activity involves an exemption from generic DCD Tier 1 Table 2.7.5-2, VAS ITAAC item 2.ii to include the rail car bay/solid radwaste system area in the scope of the auxiliary building ventilation flow rate testing and to revise the acceptance criteria for this testing to 10,300 cubic feet per minute (cfm).

These activities require an exemption from the generic DCD Tier 1 tables that are involved with the plant-specific DCD Tier 2 departures, and which support the associated COL Appendix C ITAAC. This enclosure requests an exemption from elements of the AP1000 (Tier 1) design information to allow a departure from the tables providing information supporting the associated ITAAC for the VCS and VAS. As discussed above, an exemption from elements of the AP1000 certified (Tier 1) design information is

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 4 of 10 requested to allow plant-specific departures to be taken from system-based ITAAC Tables 2.7.7-3, 2.7.5-1, and 2.7.5-2.

3.0 TECHNICAL JUSTIFICATION OF ACCEPTABILITY An exemption is requested to depart from AP1000 generic Design Control Document (DCD) Tier 1 material by departing from:

Tier 1 Table 2.7.7-3 by adding the two new containment recirculation fan coil unit assemblies (VCS-MS-01C and VCS-MS-01D) and their locations to the list of components that are verified by the VCS functional arrangement ITAAC provided in Tier 1 Table 2.7.7-2, ITAAC item 1; Tier 1 Table 2.7.5-1 by adding the new pressure differential instrument, VAS-033, (and editing the table to list the instruments in numeric order) to the list of instruments that are verified by Tier 1 Table 2.7.5-2, ITAAC item 2.i, to maintain a negative pressure differential in the served areas of the annex, fuel handling and radiologically controlled auxiliary buildings and are verified by Tier 1 Table 2.7.5-2, ITAAC item 3, to maintain instrument parameter displays that can be retrieved in the main control room; Tier 1 Table 2.7.5-2 by including the rail car bay/solid radwaste system area in the scope of the auxiliary building ventilation flow rate testing specified in the Inspections, Tests, and Analyses field of ITAAC item 2.i, and revising the Acceptance Criteria for this testing to 10,300 cubic feet per minute (cfm).

The change to add the two new VCS containment recirculation fan coil unit assemblies and their locations to Tier 1 Table 2.7.7-3 is consistent with proposed UFSAR Tier 2 changes to the layout and sizing of the containment recirculation fan coil unit assemblies and associated ductwork, and changes to the total required design air flow rates and total design cooling and heating requirements. These proposed VCS configuration changes do not adversely affect the ability of the VCS to perform its design functions of the VCS, as defined in UFSAR Subsection 9.4.6. The requested Tier 1 exemption will allow the inclusion of the two new containment recirculation fan coil unit assemblies in the scope of Tier 1 ITAAC Table 2.7.7-2, item 1, which already includes the two containment recirculation fan coil unit assemblies (VCS-MS-01A and VCS-MS-01B) that are currently in the certified AP1000 design.

The change to add a fourth VAS pressure differential instrument, VAS-033, including indication of its main control room display and control function, is consistent with the proposed UFSAR Tier 2 change to add this pressure differential instrument to provide indication, control, and alarm functions for the auxiliary building component cooling system (CCS) valve room. This additional pressure differential instrument supports the design functions of the VAS auxiliary/annex building ventilation subsystem by providing pressure differential instrumentation to an area of the auxiliary building that is remote and physically separate from the auxiliary building areas that are currently monitored and controlled by the three existing VAS pressure differential instruments. The requested Tier 1 exemption will allow the inclusion of the new, fourth pressure differential instrument in the scope of Tier 1 ITAAC Table 2.7.5-2, ITAAC items 2.i and 3, which already include the three VCS pressure differential instruments, VAS-030, VAS-032, and VA-034 (currently identified as VAS-033), that are currently in the certified

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 5 of 10 AP1000 design. The change to rearrange the order of the instruments listed in Table 2.7.5-1 is editorial, and does not adversely affect implementation of the ITAAC involving the instruments in this table.

As per UFSAR Subsection 9.4.3.2.1.2, the rail car bay/solid waste system area is included in the plant areas served by the VAS subsystem that also serves the fuel handling area; therefore, the change to include the rail car bay/solid radwaste system area in the scope of the auxiliary building ventilation flow rate testing specified in the Inspections, Tests, and Analyses field of Tier 1 Table 2.7.5-2, ITAAC item 2.i, is consistent with the subsystem design as described in the UFSAR, and provides a more comprehensive description of the test performed to verify the ability of the VAS to maintain the areas served at a slightly negative pressure relative to the atmosphere or adjacent clean plant areas. Additionally, the change to the Acceptance Criteria for this ventilation flow testing is consistent with the revised total ventilation flow rates provided by the fuel handling area ventilation subsystem as a result of the reduction in heat loads in the areas serviced by the VAS. The requested Tier 1 exemption will allow the change to the scope and acceptance criteria for the ventilation flow testing in Tier 1 ITAAC Table 2.7.5-2, ITAAC item 2.i, to be consistent with the description of this subsystem and the reduced flow requirements.

Therefore, the containment recirculation cooling system (VCS) and radiologically controlled area ventilation system (VAS) will continue to provide their design functions following implementation of the proposed changes.

Detailed technical justification supporting this request for exemption is provided in Section 2 of the associated License Amendment Request in Enclosure 1 of this letter.

4.0 JUSTIFICATION OF EXEMPTION 10 CFR Part 52, Appendix D, Section VIII.A.4 and 10 CFR 52.63(b)(1) govern the issuance of exemptions from elements of the certified design information for AP1000 nuclear power plants. Because the Licensee has identified changes to the system-based ITAAC information as presented in Tier 1 Tables 2.7.7-3, 2.7.5-1, and 2.7.5-2, an exemption from the certified design information in Tier 1 is needed.

10 CFR Part 52, Appendix D, and 10 CFR 50.12, §52.7, and §52.63 state that the NRC may grant exemptions from the requirements of the regulations provided six conditions are met: 1) the exemption is authorized by law [§50.12(a)(1)]; 2) the exemption will not present an undue risk to the health and safety of the public [§50.12(a)(1)]; 3) the exemption is consistent with the common defense and security [§50.12(a)(1)]; 4) special circumstances are present [§50.12(a)(2)(ii)]; 5) the special circumstances outweigh any decrease in safety that may result from the reduction in standardization caused by the exemption [§52.63(b)(1)]; and 6) the design change will not result in a significant decrease in the level of safety [Part 52, App. D, VIII.A.1].

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 6 of 10 The requested exemption to change the system-based ITAAC information as presented in Tier 1 Table 2.7.7-3 for the VCS and Tier 1 Tables 2.7.5-1 and 2.7.5-2 for the VAS satisfies the criteria for granting specific exemptions, as described below.

1. This exemption is authorized by law The NRC has authority under 10 CFR 52.63, §52.7, and §50.12 to grant exemptions from the requirements of NRC regulations. Specifically, 10 CFR 50.12 and §52.7 state that the NRC may grant exemptions from the requirements of 10 CFR Part 52 upon a proper showing. No law exists that would preclude the changes covered by this exemption request. Additionally, granting of the proposed exemption does not result in a violation of the Atomic Energy Act of 1954, as amended, or the Commissions regulations.

Accordingly, this requested exemption is authorized by law, as required by 10 CFR 50.12(a)(1).

2. This exemption will not present an undue risk to the health and safety of the public The proposed exemption from the requirements of 10 CFR 52, Appendix D, Section III.B would allow changes to elements of the plant-specific Tier 1 DCD to depart from the AP1000 certified (Tier 1) design information. The plant-specific DCD Tier 1 will continue to reflect the approved licensing basis for VEGP Units 3 and 4, and will maintain a consistent level of detail with that which is currently provided elsewhere in Tier 1 of the DCD. Therefore, the affected plant-specific DCD Tier 1 ITAAC will continue to serve their required purpose.

The VAS and VCS changes do not introduce any new industrial, chemical, or radiological hazards that would represent a public health or safety risk, nor do they modify or remove any design or operational controls or safeguards intended to mitigate any existing on-site hazards. Furthermore, the proposed changes would not allow for a new fission product release path, result in a new fission product barrier failure mode, or create a new sequence of events that would result in fuel cladding failures. These changes do not represent any adverse impact to the design functions of the VAS or VCS, or their ability to protect the health and safety of the public. Accordingly, these changes do not present an undue risk from any existing or proposed equipment or systems.

Therefore, the requested exemption from 10 CFR 52, Appendix D, Section III.B would not present an undue risk to the health and safety of the public.

3. The exemption is consistent with the common defense and security The exemption from the requirements of 10 CFR 52, Appendix D, Section III.B would change the list of VCS equipment and locations in Tier 1 Table 2.7.7-3, the list of VAS pressure differential instruments and main control room display requirements in Tier 1 Table 2.7.5-1, and the auxiliary building VAS ventilation flow rate testing scope and acceptance criterion in Tier 1 Table 2.7.5-2 in the plant-specific DCD Tier 1, thereby departing from the AP1000 certified (Tier 1) design information. The proposed exemption will enable performance of the ITAAC associated with these changed elements, by reflecting the current design information for the systems, structures, and components (SSCs) that are referenced in these ITAAC tables. The exemption does not

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 7 of 10 adversely impact the design, function, or operation of any plant SSCs associated with the facilitys physical or cyber security, and therefore does not adversely affect any plant equipment that is necessary to maintain a safe and secure plant status. The proposed exemption has no adverse impact on plant security or safeguards.

Therefore, the requested exemption is consistent with the common defense and security.

4. Special circumstances are present 10 CFR 50.12(a)(2) lists six special circumstances for which an exemption may be granted. Pursuant to the regulation, it is necessary for one of these special circumstances to be present in order for the NRC to consider granting an exemption request. The requested exemption meets the special circumstances of 10 CFR 50.12(a)(2)(ii). That subsection defines special circumstances as when Application of the regulation in the particular circumstances would not serve the underlying purpose of the rule or is not necessary to achieve the underlying purpose of the rule.

The rule under consideration in this request for exemption is 10 CFR 52, Appendix D, Section III.B, which requires that a licensee referencing the AP1000 Design Certification Rule (10 CFR Part 52, Appendix D) shall incorporate by reference and comply with the requirements of Appendix D, including Tier 1 information. The VEGP Units 3 and 4 COLs reference the AP1000 Design Certification Rule and incorporate by reference the requirements of 10 CFR Part 52, Appendix D, including Tier 1 information. The underlying purpose of Appendix D,Section III.B is to describe and define the scope and contents of the AP1000 design certification, and to require compliance with the design certification information in Appendix D.

The proposed exemption would allow changes to the location, configuration, and test acceptance criteria in plant-specific Tier 1 Tables 2.7.5-1, 2.7.5-2, and 2.7.7-3 to conform to the corresponding design details for proposed changes to equipment in the radiologically controlled area ventilation system (VAS) and containment recirculation cooling system (VCS). These changes have been evaluated and confirmed to support the conclusions of the supporting design analyses; therefore, implementation of these changes will not adversely affect the ability of the VAS and VCS to accomplish their design functions.

The proposed changes described above maintain the design functions of the nonsafety-related ventilation systems and the structures, systems, or components (SSCs) in areas served by these systems. This change does not impact the ability of any SSCs to perform their functions or negatively impact safety. Furthermore, the proposed changes to the information in Tier 1 Tables 2.7.5-1, 2.7.5-2 and 2.7.7-3 are consistent with format and content of other similar information currently provided in these Tier 1 tables.

Accordingly, this change to the certified information will enable the licensee to safely verify the construction of the AP1000 facility consistent with the design certified by the NRC in 10 CFR Part 52, Appendix D.

Therefore, special circumstances are present, because application of the current generic certified design information in Tier 1 as required by 10 CFR Part 52, Appendix D, Section III.B, in the particular circumstances discussed in this request is not necessary to achieve the underlying purpose of the rule.

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 8 of 10

5. The special circumstances outweigh any decrease in safety that may result from the reduction in standardization caused by the exemption The exemption from the requirements of 10 CFR 52, Appendix D, Section III.B would change elements of the plant-specific DCD Tier 1 by departing from standard AP1000 certified (Tier 1) design information. This exemption would allow a change to system based ITAAC information presented in Tier 1 Tables 2.7.7-3, 2.7.5-1, and 2.7.5-2.

Based on the nature of the proposed changes to the generic Tier 1 information and the understanding that these changes were identified during the design finalization process for the AP1000, it is expected that this exemption will be requested by other AP1000 licensees and applicants. However, even if other AP1000 licensees and applicants do not request this same departure, the special circumstances will continue to outweigh any decrease in safety from the reduction in standardization because the design functions of the nonsafety-related ventilation systems associated with this request will continue to be maintained. Furthermore, the justification provided in the license amendment request and this exemption request and the associated mark-ups demonstrate that there is a limited change from the standard information provided in the generic AP1000 DCD, which is offset by the special circumstances identified above.

Therefore, the special circumstances associated with the requested exemption outweigh any decrease in safety that may result from the reduction in standardization caused by the exemption.

6. The design change will not result in a significant decrease in the level of safety.

The proposed exemption would allow departure from AP1000 generic Tier 1 DCD information by revising Tier 1 Table 2.7.7-3 to include two new containment recirculation fan coil unit assemblies and their locations, Tier 1 Table 2.7.5-1 to add auxiliary building pressure differential indicator, VAS-034, as the last row of the table (and editing the table to list the instruments in numeric order), and Tier 1 Table 2.7.5-2 to include the rail car bay/solid radwaste system area in the scope of the auxiliary building ventilation flow rate testing and revise the Acceptance Criteria for this testing to align with system design calculations. The affected systems, VAS and VBS, serve no safety-related functions, and the proposed changes do not have an adverse effect on the ability of any safety-related SSCs to perform their design basis functions.

As a result of the limited-scope and nature of the proposed changes associated with this exemption request, no systems or equipment will be adversely impacted such that there are new failure modes introduced by these changes and the design functions provided by the nonsafety-related VAS and VCS will be maintained.

Because, with the proposed changes, the VAS and VCS continue to perform their design functions and the level of safety provided by the current systems and equipment in areas served by these systems is unchanged, it is concluded that the design change associated with the proposed exemption will not result in a significant decrease in the level of safety.

5.0 RISK ASSESSMENT A risk assessment was not determined to be applicable to address the acceptability of this proposal.

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 9 of 10 6.0 PRECEDENT EXEMPTIONS None identified.

7.0 ENVIRONMENTAL CONSIDERATION

The Licensee requests a departure from elements of the certified information in Tier 1 of the generic AP1000 DCD. The Licensee has determined that the proposed departure would require a permanent exemption from the requirements of 10 CFR 52, Appendix D, Section III.B, Design Certification Rule for the AP1000 Design, Scope and Contents, with respect to installation or use of facility components located within the restricted area, as defined in 10 CFR Part 20, or which changes an inspection or a surveillance requirement; however, the Licensee evaluation of the proposed exemption has determined that the proposed exemption meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).

Based on the above review of the proposed exemption, the Licensee has determined that the proposed activity does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in the individual or cumulative occupational radiation exposure. Accordingly, the proposed exemption meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), an environmental impact statement or environmental assessment of the proposed exemption is not required.

Specific details of the environmental considerations supporting this request for exemption are provided in Section 5 of the associated License Amendment Request provided in Enclosure 1 of this letter.

8.0 CONCLUSION

The Licensee requests a permanent exemption from elements of AP1000 design certification information reflected in Tier 1. The proposed changes to Tier 1 are necessary to revise ITAAC Table 2.7.7-3, Table 2.7.5-1, and Table 2.7.5-2 in the plant-specific DCD Tier 1 to reflect proposed plant-specific design. The proposed exemption would allow departure from AP1000 generic Tier 1 DCD information by revising Tier 1 Table 2.7.7-3 to include two new containment recirculation fan coil unit assemblies and their locations, Tier 1 Table 2.7.5-1 to include a new pressure differential instrument, VAS-033 (and editing the table to list the instruments in numeric order), and Tier 1 Table 2.7.5-2 to include the rail car bay/solid radwaste system area in the scope of the auxiliary building ventilation flow rate testing and revise the Acceptance Criteria for this testing to align with system design calculations. These Tier 1 changes reflect corresponding changes proposed to UFSAR Tier 2 information to enhance the design of the ventilation systems. The exemption request meets the requirements of 10 CFR 52.63, Finality of design certifications, 10 CFR 52.7, Specific exemptions, 10 CFR 50.12, Specific exemptions, and 10 CFR 52 Appendix D, Design Certification Rule for the AP1000. Specifically, the exemption request meets the criteria of 10 CFR 50.12(a)(1) in that the request is authorized by law, presents no undue risk to public

ND-17-1499 Exemption Request: Ventilation System Changes (LAR-16-030R1)

Page 10 of 10 health and safety, and is consistent with the common defense and security.

Furthermore, approval of this request does not result in a significant decrease in the level of safety, satisfies the underlying purpose of the AP1000 Design Certification Rule, and does not present a significant decrease in safety as a result of a reduction in standardization.

9.0 REFERENCES

None

Southern Nuclear Operating Company ND-17-1499 Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

(This Enclosure consists of 21 pages, including this cover page.)

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 2 of 21 A. Change to Configuration of the Containment Recirculation Fan Coil Unit Assemblies

1. Tier 1 Section 2.7.7, Containment Recirculation Cooling System, Table 2.7.7-3,

[VEGP Tier 1, pg. 2.7.7-2]

[VEGP Unit 3 COL, Appendix C, pg. C-400]

[VEGP Unit 4 COL, Appendix C, pg. C-400]

Revise Tier 1 information, as shown below:

Table 2.7.7-3 Component Name Tag No.

Component Location Reactor Containment Recirculation Fan Coil Unit Assembly A VCS-MS-01A Containment Reactor Containment Recirculation Fan Coil Unit Assembly B VCS-MS-01B Containment Reactor Containment Recirculation Fan Coil Unit Assembly C VCS-MS-01C Containment Reactor Containment Recirculation Fan Coil Unit Assembly D VCS-MS-01D Containment

2. UFSAR Section 1.2, General Plant Description, Subsection 1.2.4.1, Containment Building Revise Tier 2 information in the seventh paragraph under the Equipment Arrangement heading, as follows:

Two Four containment recirculation cooling units fan coil unit assemblies are located adjacent to the steam generator compartments. Each unit consists of two a vane axial fans, cooling coils, and the associated exit ducts and inlet plenum. The four recirculation fans fan coil unit assemblies are connected to the common exit plenum (ring header).

Several vertical ducts branch off from the ring header to provide cooling flow to the lower compartments in the containment while other vertical ducts are directed up to provide cooling flow to the upper regions of the containment vessel.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 3 of 21

3. UFSAR Section 9.2, Water Systems, Figure 9.2.7-1 (Sheet 3 of 4), Simplified Central Chilled Water System Piping and Instrumentation Diagram (REF) VWS 003:

Revise Tier 2 information to add new containment recirculation fan coil unit assembly, VCS-MS-01C, to the units served by the central chilled water system (VWS) and alternately by the hot water heating system (VYS), as depicted below in the excerpt from the left side of the figure:

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 4 of 21 Revise Tier 2 information to add new containment recirculation fan coil unit assembly, VCS-MS-01D, to the units served by the VWS and alternately VYS, as depicted below in the excerpt from the right side of the figure:

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Page 5 of 21

4. UFSAR Section 9.4, Air-Conditioning, Heating, Cooling, and Ventilation System, Subsection 9.4.6.2.1, General

Description:

Revise Tier 2 text in the first paragraph, as follows:

The containment recirculation cooling system is comprised of two 100 four 50 percent capacity skid-mounted fan coil unit assemblies with a total of four 50 percent capacity fan coil units which connect to a common duct ring header and distribution system. Each fan coil unit assembly contains a fan and associated cooling coil banks. The two fan coil unit assemblies are located on a platform two platforms at elevation 153-0, with two fan coil unit assemblies occupying each platform. The platforms are located approximately 180 degrees apart to provide a proper return air and mixing pattern through the ring header. The top of the ring header is approximately at elevation 176-6. The ring header and the fan assemblies are designed to provide uniform air and temperature distribution inside the containment, considering the possibility that one fan coil unit assembly may be out of service.

5. UFSAR Section 9.4, Subsection 9.4.6.2.2, Component

Description:

Revise the Containment Recirculation Fan Coil Units heading and Tier 2 text in the first paragraph under this heading, as follows:

Containment Recirculation Fan Coil Units Assemblies Each 50 percent capacity fan coil unit assembly consists of two separate but physically connected 50 percent capacity fan coil units. Each fan coil unit assembly is comprised of a return air mixing plenum section with a physical barrier in the middle and three two cooling coils attached to each of the four the sides of each plenum section. The cooling coils are counterflow finned tubular type. The cooling coils are rated and meet the performance requirements in accordance with ANSI/ARI 410 (Reference 12) and ASHRAE 33 (Reference 11).

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 6 of 21

6. UFSAR Section 9.4, Subsection 9.4.6.2.3, System Operation:

Revise Tier 2 text under the Normal Plant Operation heading, as follows:

During normal plant operation, one of the two 50 percent capacity fans in each fan coil unit assembly assemblies on each platform draws air from the upper levels of the operating floor and delivers cooling air through the ring duct and the secondary ductwork distribution system to the cubicles, compartments, and access areas above and below the operating floor. In addition, cooling air is delivered to the reactor cavity and reactor support areas to maintain appropriate local area and concrete temperatures. The normal supply temperature is 60F The nominal supply air temperature provided by the fan coil unit assemblies during normal operation is 70F in order to meet the environmental design requirements during various modes of operation.

As the supply air absorbs the heat released from various components inside containment, return air rises through vertical passages and openings due to its lower density to the upper containment level where it is again drawn into the fan coil units unit assemblies, cooled, dehumidified, and recirculated.

The standby fans coil units will be started automatically if one of the following events occurs:

Air discharge flow rate from the operating fans decreases to a predetermined setpoint Electrical and/or control power is lost Fan coil unit supply fans Fans are connected to 480V buses with backup power supply from the onsite standby diesel generators. Following a reactor shutdown when the containment air temperature is below a predetermined temperature, the fan coil units cooling water supply to the four fan coil unit assemblies will be manually realigned by the operators from the central chilled water system to the hot water heating system. Refer to Subsection 9.2.7 for further details.

Revise Tier 2 text under the Integrated Leak Rate Testing Operation heading, as follows:

During integrated leak rate testing, fan coil unit assembly operation is controlled by the main control room operator. The fan coil unit vaneaxial fans are operated at low speed to prevent the fan motors from exceeding their rated horsepower while equalizing the containment air temperature and pressure which could affect the containment integrated leak rate testing results. The recirculation fan coil units unit assemblies draw air from the upper levels of the operating floor and deliver airflow through the ring header and its distribution ductwork that is connected to equipment compartments, cubicles, and access areas above and below the operating floor.

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Page 7 of 21

7. UFSAR Section 9.4, Table 9.4.6-1, Component Data - Containment Recirculation Cooling System Containment Recirculation Fan Coil Unit Subsystem (Nominal Values):

Revise Tier 2 information in this table, as follows:

Table 9.4.6-1 Component Data - Containment Recirculation Cooling System Containment Recirculation Fan Coil Unit Subsystem (Nominal Design Values)

Reactor Containment Recirculation Fan Coil Unit Assemblies Quantity 2 4 Fan coil units per assembly 2

System capacity per assembly (%)

100 50 Fan Data (per assembly)

Quantity (fans/unit) 1 Type Vaneaxial Normal design air flow (scfm @ 0 psig) 62,800 77,000 Low speed design air flow (scfm @ 59 psig) 37,200 122,700 Fan total static pressure (in.wg) 11 Cooling Coil Data (per assembly)

Quantity (coil banks/unit) 3 4 (2 coils/bank)

Total cooling load capacity (Btu/hr) 3,804,500 4,816,000 Total chilled water flow rate (gpm) 475 600 Total heating load capacity (Btu/hr) 2,247,857 2,437,000 Total hot water flow rate (gpm) 225 63

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 8 of 21

8. UFSAR Section 9.4, Figure 9.4.6-1, Simplified Containment Recirculation Cooling System Piping and Instrumentation Diagram (REF) VCS 001:

Revise Tier 2 information to change the number and configuration of the containment recirculation fan coil unit assemblies, as depicted below in the excerpt from the left side of the figure:

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 9 of 21 Revise Tier 2 information to change the number and configuration of the containment recirculation fan coil unit assemblies, as depicted below in the excerpt from the right side of the figure:

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 10 of 21 B. Addition of Fourth VAS Pressure Differential Instrument

1. Tier 1 Section 2.7.5, Radiologically Controlled Area Ventilation System, Table 2.7.5-1:

[VEGP Tier 1, pg. 2.7.5-1]

[VEGP Unit 3 COL, Appendix C, pg. C-393]

[VEGP Unit 4 COL, Appendix C, pg. C-393]

Revise Tier 1 information, as shown below:

Table 2.7.5-1 Equipment Tag No.

Display Control Function Fuel Handling Area Pressure Differential Indicator VAS-030 Yes Annex Building Pressure Differential Indicator VAS-032 Yes Auxiliary Building Pressure Differential Indicator VAS-033 Yes Fuel Handling Area Pressure Differential Indicator VAS-030 Yes Auxiliary Building Pressure Differential Indicator VAS-034 Yes

2. Tier 2 - UFSAR Section 9.4, Air-Conditioning, Heating, Cooling, and Ventilation System, Subsection 9.4.3.5, Instrumentation Applications:

Revise Tier 2 information in the fourth paragraph, as follows:

Differential pressure indication and high differential pressure alarms are provided for the filters in the air handling units and room coolers. Pressure differential indication and alarms are provided via instruments (VAS-030, VAS-032, and VAS-033, and VAS-034) to control the negative pressure in the fuel handling area of the auxiliary building, and in the radiologically controlled areas of the auxiliary and annex buildings.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 11 of 21 C. Reduction in VAS Fuel Handling Area Ventilation Subsystem Flow and Changes to Radionuclide Specific Maximum Airborne Radioactivity Concentrations (and Parameters and Assumptions) in the Auxiliary Building, including the fuel handling area.

1. Tier 1 Section 2.7.5, Radiologically Controlled Area Ventilation System, Table 2.7.5-2, Inspections, Tests, Analyses, and Acceptance Criteria:

[VEGP Tier 1, pg. 2.7.5-2]

[VEGP Unit 3 COL, Appendix C, pg. C-394]

[VEGP Unit 4 COL, Appendix C, pg. C-394]

Revise Tier 1 information in this table, as shown below:

Table 2.7.5-2 Inspections, Tests, Analyses, and Acceptance Criteria Design Commitment Inspections, Tests, Analyses Acceptance Criteria

2. The VAS maintains each building area at a slightly negative pressure relative to the atmosphere or adjacent clean plant areas.

i) Testing will be performed to confirm that the VAS maintains each building at a slightly negative pressure when operating all VAS supply AHUs and all VAS exhaust fans.

i) The time average pressure differential in the served areas of the annex, fuel handling and radiologically controlled auxiliary buildings as measured by each of the instruments identified in Table 2.7.5-1 is negative.

ii) Testing will be performed to confirm the ventilation flow rate through the auxiliary building fuel handling and rail car bay/solid radwaste system areas area when operating all VAS supply AHUs and all VAS exhaust fans.

ii) A report exists and concludes that the calculated exhaust flow rate based on the measured flow rates is greater than or equal to 15,300 10,710 cfm.

iii) Testing will be performed to confirm the auxiliary building radiologically controlled area ventilation flow rate when operating all VAS supply AHUs and all VAS exhaust fans.

iii) A report exists and concludes that the calculated exhaust flow rate based on the measured flow rates is greater than or equal to 22,500 cfm.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 12 of 21

2. UFSAR Subsection 9.1.3.1.4 Spent Fuel Pool Purification:

Revise Tier 2 information in the first bullet, as follows:

The spent fuel pool cooling system is designed to limit exposure rates to personnel on the spent fuel pool fuel handling machine to less than 2.5 millirem per hour. This corresponds to an activity level in the water of approximately 0.005 microcurie per gram for the dominant gamma-emitting isotopes at the time of refueling.

3. UFSAR Table 9.1-3 Component Data - Spent Fuel Pool Cooling and Purification System:

Revise Tier 2 information in this table, as follows:

Spent Fuel Pool Demineralizers Number 2

Nominal flow (gallons/minute) 250200 Spent Fuel Pool Filter Number 2

Nominal flow (gallons/minute) 250200

4. UFSAR Section 9.4, Air-Conditioning, Heating, Cooling, and Ventilation System, Subsection 9.4.3.2.1.1, Auxiliary/Annex Building Ventilation Subsystem:

Revise Tier 2 information in the first paragraph, as follows:

The auxiliary/annex building ventilation subsystem serves radiologically controlled equipment, piping and valve rooms and adjacent access and staging areas. See Figure 9.4.3-1, sheet 2 of 3, for a complete listing of rooms and corridors serviced by this subsystem. The auxiliary/annex building ventilation subsystem consists of two 50 percent capacity supply air handling units of about 18,00014,000 scfm each, a ducted supply and exhaust air system, isolation dampers, diffusers and registers, exhaust fans, automatic controls and accessories.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 13 of 21

5. UFSAR Section 9.4, Air-Conditioning, Heating, Cooling, and Ventilation System, Subsection 9.4.3.2.1.2, Fuel Handling Area Ventilation Subsystem:

Revise Tier 2 information in the first paragraph, as follows:

The fuel handling area ventilation subsystem serves the fuel handling area, rail car bay/filter storage area, resin transfer pump/valve room, spent resin tank room, waste disposal container area, WSS (spent resin) valve/piping area and elevator machine room. The fuel handling area ventilation subsystem consists of two 50 percent capacity supply air handing units of about 9,500 4,900 scfm each, a ducted supply and exhaust air system, isolation dampers, diffusers, registers, exhaust fans, automatic controls and accessories. Hot water heating coils supplied with water from the hot water heating system (VYS) and cooling coils supplied with water from the central chilled water system (VWS) are used to maintain ambient room temperatures within the normal range. The ventilation airflow capacity is designed to maintain environmental conditions that support worker efficiency during fuel handling operations based on a maximum wetbulb globe temperature of 80°F (96°F drybulb) as defined by EPRI NP-4453 (Reference 22). The supply air handling units are located in the south air handling equipment room of the annex building at elevation 135-3. They are connected to the air intake plenum #2 located at the south end of the annex building. This common intake plenum is described in Subsection 9.4.2. The units discharge into a ducted supply distribution system which is routed to the fuel handling and rail car bay/filter storage areas of the auxiliary building.

The supply and exhaust ducts are provided with isolation dampers that close when high airborne radioactivity in the exhaust air or high pressure differential with respect to the outside atmosphere is detected.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 14 of 21

6. UFSAR Section 12.2, Radiation Sources, Table 12.2-24, Parameters and Assumptions Used for Calculating Fuel Handling Area Airborne Radioactivity Concentrations:

Revise Tier 2 information in this table, as follows:

Parameter/Assumption Value Assumed fuel load Full core offload Ventilation flow through fuel handling area(1) 17,000 9,500 cfm(2)

Iodine filter efficiency 0

Particulate filter efficiency 0.99 Fuel handling area free air volume 200,000 225,450 ft3 Fuel defects 0.25%

Time from shutdown to reactor vessel head removal 100 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months Refueling time 10 days Spent fuel pool purification flow rate 250 150 gpm Partition coefficients:

Noble gases Freely released Tritium 1

Halogens 100 Others 1,000 Evaporation rate of spent fuel pool water 486 430 lbs/hr Spent fuel pool Reactor coolant tritium concentration 1.0 3.5 Ci/g Notes:

1. This flow rate is defined as the sum of the fuel handling area exhaust fan flows minus the rail car bay/solid radwaste system exhaust flow from room 12562 (fuel handling area) and exhaust flow from room 12562 to room 12471 (solid radwaste system valve/piping area).

2. This is the nominal expected ventilation flow rate. For conservatism, the calculated airborne radioactivity concentrations are based on a 10% lower flow rate.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 15 of 21

7. UFSAR Section 12.2, Radiation Sources, Table 12.2-25, Fuel Handling Area Airborne Radioactivity Concentrations:

Revise Tier 2 information in this table, as follows:

Isotope Activity(2)

Cr-51 8.7E-12 4.4E-12 Mn-54 4.8E-12 2.4E-12 Fe-55 3.7E-12 1.8E-12 Fe-59 8.7E-13 4.3E-13 Co-58 1.4E-11 8.0E-11 Co-60 1.6E-12 7.9E-13 Br-83 2.3E-16 Kr-83m 3.7E-17 Kr-85m 7.6E-16 4.6E-12 Kr-85 2.2E-10 4.2E-10 Kr-87 2.7E-20 Kr-88 2.7E-19 1.4E-13 Sr-89 4.2E-12 1.4E-12 Sr-90 3.7E-13 6.6E-14 Sr-91 2.1E-14 6.2E-14 Sr-92 9.1E-19 Y-90 1.5E-14 9.4E-15 Y-91 1.6E-13 1.8E-13 Y-92 2.4E-17 Y-93 1.6E-13 5.1E-15 Zr-95 1.2E-11 2.1E-13 Nb-95 8.2E-12 2.0E-13 Mo-99 7.1E-11 1.7E-10 Tc-99m 1.4E-15 7.7E-13 Ru-103 2.2E-10 1.7E-13 Ag-110m 4.0E-11 3.4E-13 Te-127m 2.9E-18 1.1E-12 Te-129m 5.4E-12 3.5E-12 Te-131m 4.9E-12 4.0E-12 Te-132 2.3E-11 6.5E-11 I-129 1.6E-16

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 16 of 21 I-130 3.5E-18 4.8E-12 I-131 1.0E-08 7.7E-09 I-132 3.0E-15 I-133 1.8E-09 3.3E-09 I-135 2.3E-12 5.4E-11 Xe-131m 1.7E-10 3.8E-10 Xe-133m 3.1E-10 1.2E-09 Xe-133 2.2E-08 5.8E-08 Xe-135 4.2E-12 4.3E-10 Cs-134 2.2E-10 8.1E-10 Cs-136 2.3E-11 1.1E-09 Cs-137 3.0E-10 6.7E-10 Ba-140 3.2E-10 1.2E-12 La-140 1.5E-10 1.6E-13 Ce-141 4.4E-12 2.0E-13 Ce-143 1.1E-11 6.7E-14 Pr-143 9.0E-11 1.8E-13 Ce-144 1.3E-10 1.5E-13 H-3 3.9E-06 6.4E-06 Rb-86 8.7E-12 Tc-99 2.6E-15 Ru-106 5.7E-14 Te-125m 1.2E-13 Te-127 1.0E-13 Total (excluding tritium) 3.7E-08 7.4E-08 Iodines 1.2E-08 1.1E-08 Particulates 1.7E-09 2.9E-09 Noble Gases 2.3E-08 6.0E-08 (See next page for markup of Table 12.2-25 Notes 1 and 2)

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 17 of 21 Notes:

1. This The maximum activity concentration is calculated to occur 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months after removal of the head, or 102 50 hours5.787037e-4 days 0.0139 hours 8.267196e-5 weeks 1.9025e-5 months after shutdown in this case.

2. The following nuclides are expected to exist in the FHA at the time of maximum airborne concentrations with individual nuclide activity concentrations less that than 1.0E-20 Ci/cm3:

56Mn, 83Br, 84Br, 85Br, 83mKr, 87Kr, 89Kr, 88Rb, 89Rb, 92Sr, 91mY, 92Y, 103mRh, 129Te, 131Te, 134Te, 129I, 132I, 134I, 135mXe, 137Xe, 138Xe, and138Cs, 137mBa, and 144Pr.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 18 of 21

8. UFSAR Section 12.2, Radiation Sources, Table 12.2-26, Parameters and Assumptions Used for Calculating Auxiliary Building Airborne Radioactivity Concentrations:

Revise Tier 2 information in this table, as follows:

Parameter/Assumption Value Ventilation exhaust flow(1) 25,000 25,320 cfm(2)

Free air volume 365,400 411,200 ft3 Primary coolant leakage to auxiliary building 20 296 lb/day Flashing fraction 0.4 Noble gases 1

Other gases 0.1 Primary coolant source term See Table 11.1-2.

Fuel defects 0.25%

Notes:

1.

This flow rate is defined as the sum of the aux/annex auxiliary/annex building exhaust fan flow minus the annex building exhaust flows from room 40357 (containment access corridor), room 40551 (containment air filtration exhaust room A), and 40552 (containment air filtration exhaust room B).

minus room 12555 (VES) and 12556 (containment access) exhaust flow.

2.

This is the nominal expected ventilation flow rate. For conservatism, the calculated airborne radioactivity concentrations are based on a 10% lower flow rate.

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 19 of 21

9. UFSAR Section 12.2, Radiation Sources, Table 12.2-27 Auxiliary Building Airborne Radioactivity Concentrations:

Revise Tier 2 information in this table, as follows:

Isotope Activity Cr-51 5.1E-12 8.6E-12 Mn-54 2.7E-12 4.5E-12 Mn-56 6.7E-10 1.1E-09 Fe-55 2.0E-12 3.3E-12 Fe-59 5.1E-13 8.6E-13 Co-58 7.5E-12 1.3E-11 Co-60 8.7E-13 1.5E-12 Br-83 1.3E-10 2.0E-10 Br-84 6.6E-11 8.1E-11 Br-85 7.8E-12 2.5E-12 Kr-83m 1.8E-09 1.1E-08 Kr-85m 8.3E-09 5.3E-08 Kr-85 2.9E-08 2.0E-07 Kr-87 4.7E-09 2.7E-08 Kr-88 1.5E-08 9.3E-08 Kr-89 3.5E-10 4.7E-10 Rb-88 6.0E-09 5.8E-09 Rb-89 2.7E-10 2.5E-10 Sr-89 4.3E-12 7.3E-12 Sr-90 1.9E-13 3.3E-13 Sr-91 6.9E-12 1.1E-11 Sr-92 1.6E-12 2.5E-12 Y-90 5.0E-14 8.6E-14 Y-91m 3.7E-12 4.9E-12 Y-91 5.4E-13 9.3E-13 Y-92 1.3E-12 2.1E-12 Y-93 4.5E-13 7.2E-13 Zr-95 6.3E-13 1.1E-12 Nb-95 6.3E-13 1.1E-12 Mo-99 8.4E-10 1.4E-09 Tc-99m 7.7E-10 1.3E-09 Ru-103 5.4E-13 9.3E-13

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 20 of 21 Rh-103m 7.6E-13 Ag-110m 1.6E-12 2.7E-12 Te-127m 3.0E-12 5.1E-12 Te-129m 1.0E-11 1.7E-11 Te-129 1.5E-11 2.1E-11 Te-131m 2.7E-11 4.4E-11 Te-131 1.7E-11 1.9E-11 Te-132 3.1E-11 5.2E-10 Te-134 4.2E-11 5.6E-11 I-129 5.9E-17 1.0E-16 I-130 4.2E-11 7.2E-11 I-131 2.8E-09 4.7E-09 I-132 3.7E-09 5.7E-09 I-133 5.1E-09 8.6E-09 I-134 8.6E-10 1.2E-09 I-135 3.1E-09 5.0E-09 Xe-131m 1.3E-08 8.6E-08 Xe-133m 1.7E-08 1.1E-07 Xe-133 1.2E-06 8.0E-06 Xe-135m 2.3E-09 6.2E-09 Xe-135 3.5E-08 2.3E-07 Xe-137 6.6E-10 1.0E-09 Xe-138 2.4E-09 8.8E-09 Cs-134 2.7E-09 4.6E-09 Cs-136 4.0E-09 6.6E-09 Cs-137 2.0E-09 3.3E-09 Cs-138 1.5E-09 1.8E-09 Ba-137m 1.9E-09 5.3E-10 Ba-140 4.1E-12 6.6E-12 La-140 1.0E-11 2.1E-12 Ce-141 6.1E-13 1.1E-12 Ce-143 5.6E-13 9.3E-13 Pr-143 5.9E-13 1.0E-12 Ce-144 4.6E-13 8.0E-13 Pr-144 4.6E-13 4.6E-13 H-3 1.4E-08 2.3E-07

ND-17-1499 Revised Proposed Changes to the Licensing Basis Documents (LAR-16-030R1)

Page 21 of 21 Total 1.4E-06 9.1E-06 Iodines 1.6E-08 2.5E-08 Particulates 2.1E-08 2.8E-08 Noble Gases 1.4E-06 8.8E-06

ND-17-1499, Revised Request for License Amendment and Exemption: Ventilation System Changes (LAR-16-030R1)

Contents

Text

Enclosures:

SUMMARY

SUMMARY

2.0 BACKGROUND

7.0 ENVIRONMENTAL CONSIDERATION

8.0 CONCLUSION

9.0 REFERENCES

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Description:

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ND-17-1499, Revised Request for License Amendment and Exemption: Ventilation System Changes (LAR-16-030R1)

Text

Enclosures:

SUMMARY

SUMMARY

2.0 BACKGROUND

7.0 ENVIRONMENTAL CONSIDERATION

8.0 CONCLUSION

9.0 REFERENCES

Description:

Description:

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