ND-20-0093, Supplement to Request for License Amendment: Tornado Missile Protection for Main Steam Vent Stacks and Wall 11 (LAR-19-014S1)
| ML20045D590 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 02/14/2020 |
| From: | Whitley B Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LAR-19-014S1, ND-20-0093 | |
| Download: ML20045D590 (10) | |
Text
B. H. Whitley Southern Nuclear Director Operating Company, Inc.
Regulatory Affairs 3535 Colonnade Parkway Birmingham, AL 35243 Tel 205.992.7079 Fax 205.992.7722 February 14, 2020 Docket Nos.: 52-025 ND-20-0093 52-026 10 CFR 50.90 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Southern Nuclear Operating Company Vogtle Electric Generating Plant Units 3 and 4 Supplement to Request for License Amendment:
Tornado Missile Protection for Main Steam Vent Stacks and Wall 11 (LAR-19-014S1)
Ladies and Gentlemen:
On August 16, 2019, pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC) requested an amendment to the combined licenses (COLs) for Vogtle Electric Generating Plant (VEGP) Units 3 and 4 (License Numbers NPF-91 and NPF-92, respectively) [ADAMS Accession Number ML19228A241]. The requested amendment proposes to depart from Tier 2 information in the Updated Final Safety Analysis Report (UFSAR) (which includes the plant-specific DCD Tier 2 information).
The requested license amendment (LAR-19-014) proposes changes to the evaluation of the auxiliary building main steam safety valve (MSSV) vent stack openings and the auxiliary building Wall 11 openings for protection from tornado-generated missiles.
That submittal built upon discussions held with the staff on April 26, 2018 (ML18117A351),
April 11, 2019 (ML19114A286), and July 25, 2019.
After the NRCs audit (ML19338C151) of the technical information supporting LAR-19-014, clarifications were identified for the submittal based on the design analysis and design drawings which support the request. The material specified for a new turbine building first bay barrier discussed in the submittal is clarified in the revised technical evaluation and licensing basis markups provided in this supplement.
This supplement does not impact the scope or conclusions of the Technical Evaluation, Significant Hazards Consideration Determination, or Environmental Considerations of the original submittal.
Enclosures 1 through 5 were provided with the original submittal. provides a revision to the relevant section of the technical evaluation in Enclosure 1.
Portions of Enclosure 1 not addressed in Enclosure 6 are unaffected by this supplement.
A Southern Nuclear
U.S. Nuclear Regulatory Commission ND-20-0093 Page 2 of 4 provides revisions to portions of the licensing basis markups previously provided in. Portions of Enclosure 2 not addressed in Enclosure 7 are unaffected by this supplement.
This letter contains no regulatory commitments. This letter has been reviewed and determined not to contain security-related information. This letter does not impact the requested approval date or implementation period identified in the original submittal.
In accordance with 1 O CFR 50.91, SNC is notifying the State of Georgia by transmitting a copy of this letter and its enclosures to the designated State Official.
Should you have any questions, please contact Mr. Ryan Henderson at (205) 992-6426.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 14th of February 2020.
Respectfully submitted, Brian H. Whitley Director, Regulatory Affairs Southern Nuclear Operating Company
Enclosures:
- 1) through 5) previously provided in original submittal of LAR-19-014 dated August 16, 2019 [ML19228A241]
- 6) Vogtle Electric Generating Plant (VEGP) Units 3 and 4 - Supplement to Request for License Amendment: Tornado Missile Protection for Main Steam Vent Stacks and Wall 11 (LAR-19-014S1)
- 7) Vogtle Electric Generating Plant (VEGP) Units 3 and 4 - Revisions to Proposed Changes to Licensing Basis Documents (LAR-19-014S1)
U.S. Nuclear Regulatory Commission ND-20-0093 Page 3 of 4 cc:
Southern Nuclear Operating Company / Georgia Power Company Mr. S. E. Kuczynski (w/o enclosures)
Mr. P. P. Sena III (w/o enclosures)
Mr. M. D. Meier (w/o enclosures)
Mr. D. H. Jones (w/o enclosures)
Mr. G. Chick Mr. M. Page Mr. P. Martino Mr. D. L. McKinney (w/o enclosures)
Mr. T. W. Yelverton (w/o enclosures)
Mr. B. H. Whitley Ms. C. A. Gayheart Ms. M. Ronnlund Mr. D. L. Fulton Mr. M. J. Yox Mr. C. T. Defnall Mr. J. Tupik Ms. S. Agee Mr. M. Humphrey Ms. A. C. Chamberlain Mr. S. Leighty Mr. N. Kellenberger Mr. E. Riffle Ms. K. Roberts Mr. J. Haswell Mr. D. T. Blythe Mr. K. Warren Document Services RTYPE: VND.LI.L00 File AR.01.02.06 Nuclear Regulatory Commission Mr. W. Jones (w/o enclosures)
Ms. M. Bailey (w/o enclosures)
Mr. M. King (w/o enclosures)
Mr. C. Patel Mr. C. Santos Mr. B. Kemker Mr. J. Eargle Mr. G. Khouri Ms. S. Temple Mr. C. J. Even Mr. A. Lerch Mr. S. Walker Mr. N.D. Karlovich Ms. N. C. Coovert Mr. C. Welch Mr. J. Gaslevic
U.S. Nuclear Regulatory Commission ND-20-0093 Page 4 of 4 Mr. V. Hall Ms. K. P. Carrington Mr. M. Webb Mr. P.J. Heher State of Georgia Mr. R. Dunn Oglethorpe Power Corporation Mr. M. W. Price 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. L. Oriani (w/o enclosures)
Mr. T. Rubenstein (w/o enclosures)
Mr. M. Corletti Mr. D. Hawkins Mr. J. Coward 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
Southern Nuclear Operating Company ND-20-0093 Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Supplement to Request for License Amendment:
Tornado Missile Protection for Main Steam Vent Stacks and Wall 11 (LAR-19-014S1)
(This Enclosure consists of 4 pages, including this cover page)
ND-20-0093 Supplement to Request for License Amendment: Tornado Missile Protection for Main Steam Vent Stacks and Wall 11 (LAR-19-014S1)
Page 2 of 4 After the NRCs audit (ML19338C151) of the technical information supporting license amendment request (LAR)-19-014, clarifications were identified for the submittal based on the design analysis and design drawings which support the request. The material specified for a new turbine building first bay barrier discussed in the submittal is clarified in the revised technical evaluation and licensing basis markups provided in this supplement. This supplement does not impact the scope or conclusions of the Technical Evaluation, Significant Hazards Consideration Determination, or Environmental Considerations of the original submittal.
Replace ND-19-0855, Enclosure 1, Section 2.1.5 (pages 12-13 of 25) with the information below.
Revisions to the technical evaluation below are indicated with insertions denoted by blue underline and deletions by red strikethrough.
2.1.5 Addition of First Bay Missile Barrier A steel missile barrier is proposed to be added in the turbine building first bay at elevation 100-0 in front of the Wall 11 door to Room 12306 to eliminate the line of sight into Room 12306 and prevent sphere and artillery missiles from penetration. The missile barrier is designed in accordance with AISC N690-1994 and meets UFSAR Subsection 3.5.3 requirements.
The missile barrier is a solid steel plate with a steel support frame permanently anchored to the floor. The thickness of the steel plate prevents penetration of the 1-inch sphere missile and 8-inch artillery shell while meeting the barrier ductility requirements contained in UFSAR Subsection 3.5.3.1. The missile barrier framing and supports are sufficient to prevent bending or overturning of the barrier plate under missile impact loadings. The missile barrier anchors meet the anchorage requirements in UFSAR Subsection 3.8.4.5.1. Design and construction of fastening to concrete is in accordance with ACI 349-01, Appendix B. The material is specified on the design drawings to be as follows or steel with equal or better material properties:
Barrier plate (ASTM A572, Gr. 50)
Barrier support frame (ASTM A500, Gr. B)
Anchors (manufacturer standard)
Barrier plate (ASTM A240)
Barrier support frame (ASTM A500, Gr. B)
Anchors (ASTM A325 or ASTM A490, and ASTM F1554, Gr. 105 as required)
The missile barrier design drawings allow for the barrier plate to be ASTM A240 or ASTM A572, Gr. 50. ASTM A572, Gr. 50 is not listed as a material of construction in UFSAR Table 3.5-1 Note 3, but has equal or better material properties to ASTM A240 as allowed by the note. ASTM A572, Gr. 50 has a yield strength of 50 ksi which is better than ASTM A240 yield strength of 25 ksi.
UFSAR Table 3.5-1 Note 3 is revised to separately specify the materials for the existing and proposed first bay interior missile barriers, which are required to be made of specified steel, or steel with equal or better material properties.
ND-20-0093 Supplement to Request for License Amendment: Tornado Missile Protection for Main Steam Vent Stacks and Wall 11 (LAR-19-014S1)
Page 3 of 4 The missile barrier is proposed to be classified as seismic Category II, equipment Class D since:
- 1) This classification aligns with the philosophy outlined in NRC Generic Letter 84-01, which indicates that a classification of non-safety-related, but important to safety is appropriate for this protective function;
- 2) The level of quality applied to equipment Class D SSCs, although non-safety-related, contains additional requirements on procurement, inspection, or monitoring, which is in line with the level of quality expected for non-safety-related, but important to safety, functions; and
- 3) The level of quality applied to equipment Class D SSCs corresponds with the level of quality applied to seismic Category II structures, such as the turbine building first bay building structure, and thus commensurate with the level of quality of the structure to which they are mounted and structurally supported by (turbine building first bay building structure).
The proposed missile barrier does not affect airflow, venting, or personnel access. The proposed barrier is a solid design that eliminates line of sight to the Wall 11 door to room 12306. Personnel are still able to walk around the barrier and access room 12306. There is no impact to maintenance, testing, or inspection activities (Preservice Tests and Inspections, In-service Tests and Inspections, ASME Code,Section XI inspections). The barrier will allow clearance for the door to open and allow venting of room 12306 in the event that the main stream vent stacks are crimped (e.g., blocked).
The turbine building first bay does not have any designated fire barriers, thus the addition of missile barrier to the turbine building first bay does not affect any required fire rating in the turbine building, nor adversely impact the fire ratings of barriers in close proximity to the turbine building first bay. The alternate vent path through the doors in Rooms 12306, 12504, and 12506 do not affect fire zones or fire barriers because severe natural phenomena are not assumed to occur concurrent to a fire as described in UFSAR Subsection 9A.2.7.1.
The proposed missile barrier does not adversely impact radiologically controlled zones. The proposed missile barriers are not credited as radiological shielding.
The proposed missile barrier does not adversely impact emergency or security plans because there are no changes to the external configuration of the roof, walls, doors, or access to the nuclear island.
The proposed missile barrier does not interface with or affect safety-related equipment or a fission product barrier. No system or design function or equipment qualification would be adversely affected by the proposed changes. The proposed changes do not affect the operation of any systems or equipment. The proposed changes do not result in a new failure mode, malfunction or sequence of events that could adversely affect a radioactive material barrier or safety-related equipment.
For the doors between Rooms 12504/12506 and the turbine building first bay which may open to vent, a line of sight evaluation shows that the turbine building first bay
ND-20-0093 Supplement to Request for License Amendment: Tornado Missile Protection for Main Steam Vent Stacks and Wall 11 (LAR-19-014S1)
Page 4 of 4 structure prevents a missile from entering the turbine building first bay at elevation 135'-3" and 148'-0" except for three large openings. There is no line of sight to safe shutdown equipment if the doors are open due to geometry. Due to the angle of the missile paths from the large openings to the doors, the missile could hit the door frame but would not enter into Rooms 12504/12506. The turbine building first bay building structure is sufficient to protect safe shutdown equipment. Therefore, no barrier is required between Rooms 12504/12506 and the turbine building first bay. (See Change 2 for more discussion and for discussion of protection from an automobile missile.)
Southern Nuclear Operating Company ND-20-0093 Vogtle Electric Generating Plant (VEGP) Units 3 and 4 Revisions to Proposed Changes to Licensing Basis Documents (LAR-19-014S1)
Insertions Denoted by Blue Underline and Deletions by Red Strikethrough Omitted text is identified by three asterisks ( * * * )
(This Enclosure consists of 2 pages, including this cover page)
ND-20-0093 Revisions to Proposed Changes to Licensing Basis Documents (LAR-19-014S1)
Page 2 of 2 After the NRCs audit (ML19338C151) of the technical information supporting license amendment request (LAR)-19-014, clarifications were identified for the submittal based on the design analysis and design drawings which support the request. The material specified for a new turbine building first bay barrier discussed in the submittal is clarified in the revised technical evaluation and licensing basis markups provided in this supplement.
Replace ND-19-0855, Enclosure 2, Pages 8 of 9 with the information below which revises UFSAR Table 3.5-1, External Missile Protection Provided for Auxiliary Building Wall 11 Openings, Note 3:
Notes:
- 1. * * *
- 2. * * *
- 3. The materials of construction for the missile barriers installed on or within the turbine building first bay and on Wall 11 shall be steel as specified below, or steel with equal or better material properties:
Wall 11.2 and Wall R large opening missile barriers
- grating bar, baseplate - ASTM A240
- perimeter frame - ASTM A36 or ASTM A992
- anchors - ASTM F1554, Gr. 105 First bay interior missile barrier at elevation 117-6
- barrier plate - ASTM A240
- barrier support frame - ASTM A500, Gr. B
- anchors - ASTM A325 or ASTM A490, and ASTM F1554, Gr. 105 as required First bay interior missile barrier at elevation 100-0
- barrier plate - ASTM A572, Gr. 50
- barrier support frame - ASTM A500, Gr. B
- anchors - manufacturer standard Wall 11 missile doors
- door plate - ASTM A240
- embed plates - ASTM A572, Gr. 50
- anchors - ASTM A 1064 Wall 11 spare penetration covers
- material shall be as specified for their penetration function