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COL Docs - (External_Sender) Slides for 5/23 Public Meeting
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Vogtle PEmails From: Arafeh, Yasmeen N. <YNARAFEH@southernco.com>

Sent: Thursday, May 16, 2019 2:05 PM To: Gleaves, Bill; Patel, Chandu Cc: Habib, Donald

Subject:

[External_Sender] Slides for 5/23 Public Meeting Attachments: LAR 19-010 Slides for TEx Mtg 20190523.pdf; LAR 19-009 Slides for TEx Mtg 20190523.pdf Good Afternoon!

Attached to this email are the presentation slides for LAR-19-009 and LAR-19-010 for the 5/23/19 Public Meeting. We will be sending the draft for LAR-19-003 later this afternoon.

Please let me know if you have any questions.

Best, Yasmeen Arafeh Nuclear Development, Licensing Work: (205)992-7190 ynarafeh@southernco.com 1

Hearing Identifier: Vogtle_COL_Docs_Public Email Number: 446 Mail Envelope Properties (BN8PR04MB56354B589A7A76429EBA9339BB0A0)

Subject:

[External_Sender] Slides for 5/23 Public Meeting Sent Date: 5/16/2019 2:05:18 PM Received Date: 5/16/2019 2:05:58 PM From: Arafeh, Yasmeen N.

Created By: YNARAFEH@southernco.com Recipients:

"Habib, Donald" <Donald.Habib@nrc.gov>

Tracking Status: None "Gleaves, Bill" <Bill.Gleaves@nrc.gov>

Tracking Status: None "Patel, Chandu" <Chandu.Patel@nrc.gov>

Tracking Status: None Post Office: BN8PR04MB5635.namprd04.prod.outlook.com Files Size Date & Time MESSAGE 399 5/16/2019 2:05:58 PM image001.png 1723 LAR 19-010 Slides for TEx Mtg 20190523.pdf 1210730 LAR 19-009 Slides for TEx Mtg 20190523.pdf 265568 Options Priority: Standard Return Notification: No Reply Requested: Yes Sensitivity: Normal Expiration Date:

Recipients Received:

WEC LAR-163 (VEGP LAR-19-010): Heatup of Auxiliary Building Rooms Following Loss of HVAC or Loss of all AC Power May 23rd, 2019 1

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Purpose & Agenda Meeting Purpose

Discuss changes proposed by WEC LAR-163

Inform Staff of LAR Scope and gain feedback Agenda

Background information and context

Basis for proposed changes

Proposed changes 2

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Loss of AC Power 3

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Background

Tier 1 Table 2.2.5-4 provides heat load constraints of the main control room (MCR) and surrounding equipment rooms containing safety-related equipment

- Used to ensure the MCR remains within limits for reliable human performance for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after Main Control Room Emergency Habitability System (VES) actuation

- The rooms surrounding the MCR contain PMS and Class 1E (IDS) equipment

- Information also included in Tier 2 Table 6.4-3

VES is designed to passively cool the I&C and DC equipment rooms in an accident to ensure that safety related equipment remains functional

- This requires maintaining the room temperature below the equipment qualification (EQ) temperature limit of 120°F 4

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Reason for Change

Heat loads in the CLB were based on information available at certification prior to final placement of equipment and prior to detailed design on electrical component specifications

- Reconciliation using detailed design inputs requires updates to heat loads specified in the licensing basis Reconciled heat loads require updates to Tier 1 Table 2.2.5-4 & Tier 2 Table 6.4-3 5

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Proposed Change and Supporting Analysis

The proposed change is to revise the heat loads in the licensing basis to reflect the heat load summary used in the GOTHIC heat-up analysis of the 8 I&C/DC rooms due to a design basis accident (DBA) loss of AC power event

- Rooms 12201, 12203, 12205, 12207, 12301, 12302, 12304, and 12305

- Analyses use a conservative, initial air temperature consistent with Tech Spec Bases 3.7.6 (85°F)

WEC LAR-82 (VEGP LAR 17-001) added Tech Spec Bases (3.7.6) maximum operating temperature limit of 85ºF to the 8 rooms credited as passive heat sinks for MCR heatup

- Finalized heat load inputs based on detailed design values; including confirmation of heat load timing 6

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Termination of Loads at 24 Hours

The UFSAR currently discusses removal/disconnection of the 24-hour batteries at or before 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months is consistent with the CLB

- Note 3 of Table 3D.5-4 (Abnormal Operating Environments)

Note 3 is listed against the 120ºF limit for Aux Building

- Section 6.4.3 of the UFSAR, added as part of WEC LAR-82 (VEGP LAR 17-001)

Analysis models heat load removal at 7 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Basis for 24 Hour Heat Load Reduction

For non-LOCA events, safety-related core cooling is provided by natural circulation through the passive residual heat removal (PRHR) heat exchanger (HX) and core makeup tanks (CMTs)

- PRHR HX transfers heat from the reactor coolant system (RCS) to the in-containment refueling water storage tank (IRWST)

- Safe shutdown conditions can be maintained for greater than 14 days with closed loop cooling provided by the PRHR HX

The plant can be maintained in this condition for more than 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months without AC power under DBA conditions

- If AC power is unavailable, ADS-4 will automatically actuate at 22 hours2.546296e-4 days 0.00611 hours 3.637566e-5 weeks 8.371e-6 months (PMS timer) to ensure the plant is in a safe condition (open loop cooling) before the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months batteries are exhausted 8

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Basis for 24 Hour Heat Load Reduction

However, if the plant and RCS conditions are safe and stable (effective decay heat removal and water inventory), the operators are instructed to de-energize the PMS at the Class-1E 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months IDS batteries

- Prevents unnecessary ADS actuation

- Preserves battery capacity if ADS is required later

Thus, for a loss of AC scenario, it is expected that ADS-4 actuation will not be required and the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months batteries (and thus PMS cabinets) are disconnected before the 22 hour2.546296e-4 days 0.00611 hours 3.637566e-5 weeks 8.371e-6 months timer

- Results in a major reduction in heat loads from the PMS cabinets

In the event that ADS actuation is allowed to occur, procedures will instruct operators to take actions to reduce/maintain temperature in these compartments, including powering down 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months IDS batteries PMS heat loads will be reduced at or before 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months for Loss of AC event 9

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Licensing Basis Impacts Tier 1 Table 2.2.5-4 & Tier 2 Table 6.4-3 10

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Loss of Ventilation without Loss of AC Power 11

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Background

Loss of Ventilation without loss of AC power is an abnormal condition specified in 3D.5.2.2

- Section 3.11.3 of the UFSAR notes that loss of ventilation events will not challenge safety related equipment for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months

Heat load profiles for a loss of ventilation without loss of AC power is more limiting due to non-safety heat loads remaining in service in addition to safety related heat loads

Licensing basis states that recovery actions occur within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , but only mentions recovery of HVAC systems and not any compensatory actions (e.g., opening doors, using portable equipment) 12

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Abnormal Events Background

Abnormal events are an aging mechanism considered in the AP1000 plant for some EQ programs

No identified regulatory basis for considering abnormal events in an EQ program

- Intended to add additional margin to the equipment

These events are not design basis accidents and are not subject to the same conservative methodologies and requirements used in the development of accident environments for EQ

- UFSAR Section 3D.5.2 Abnormal Operating Conditions

plant service abnormalities that lead to short-term changes in environments.

Best estimate analyses of AP1000 plant behavior are used to determine abnormal environmental conditions. Plant recovery occurs after each event with varying degrees of time and maintenance efforts.

13

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Problem and Proposed Solution

Problem

- Description of loss of ventilation without loss of AC event is not adequately defined in licensing basis

With no actions taken, rooms may exceed EQ limit within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months

Abnormal event equipment qualification assumes multiple 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months loss of ventilation events over the course of plant life

Solution

- Update analysis and CLB to credit opening doors to affected rooms at 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months after event initiation

Preliminary analyses illustrate this to be sufficient to slow heat-up rate of affected rooms to remain below EQ limit for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months

Analyses will be completed before LAR submittal 14

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Summary of Proposed Licensing Basis Changes

Modification to Tier 2 Sections 3.11.3 and 9.4.1.2.3.2 include

- Clarifications regarding expected abnormal event duration for loss of ventilation consistent with abnormal event definitions in Section 3D.5.2

- Clarification of additional recovery actions for an unlikely, loss of ventilation event of more than 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months in affected rooms

Corresponding updates to abnormal event temperatures and environmental Zones due to updated analysis results

- UFSAR Table 3D.5-4, Abnormal Operating Environments Outside Containment

- UFSAR Table 3H.5-1 Nuclear Island: Design Temperatures for Thermal Gradient 15

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Applicable General Design Criteria

GDC-2 Design basis for protection against natural phenomena

GDC-4 Environmental and dynamic effects design bases.

GDC-29 Protection against anticipated operational occurrences.

The changes to the I&C and dc Equipment room heat loads and Auxiliary Building rooms temperatures due to a loss of HVAC/loss of AC power are included in environmental qualification of SSCs and the design of Auxiliary Building.

16

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Schedule

Pre-Submittal Meeting - Late July/Early August 2019

Submittal to NRC - Late August 209

Requested Approval - Submittal + 6 months

- LAR needed to support ITAAC Closure and UIN Submittal in April 2020 17

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

Questions?

18

- - This record was final approved on 5/16/2019 9:10:40 AM. (This statement was added by the PRIME system upon its validation)

WEC LAR-080 (VEGP LAR-19-009): Small Break LOCA Analysis May 23, 2019 1

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Meeting Purpose and Agenda Meeting Purpose

Technical exchange meeting to discuss the proposed changes in WEC LAR-080 (VEGP LAR-19-009), SBLOCA Analysis

Inform staff of LAR scope and gain feedback Agenda

Summary of changes

Background information

Discussion of proposed changes

Applicable General Design Criteria

Schedule 2

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Summary of Changes Proposed Changes

1. ADS Stage 1 Max Stroke Time Updates

2. ADS Stages 2&3 Max Stroke Times and Minimum Effective Flow Areas Updates

3. SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA Analyses Updates

4. CMT TS Minimum Volume Updates 3

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Background Information

The current licensing basis (CLB) UFSAR Chapter 15 accident analyses, as prescribed by NUREG-0800, describe analyses of various design basis accidents and demonstrate compliance of the AP1000 plant design with the acceptance criteria

The CLB for Chapter 15 accident analyses are reflected in the Core Reference Report (WCAP-17524-P-A) and represent a design input baseline of 2008

Design debt is incorporated into applicable safety analyses updates from previously approved LARs, including:

- WEC LAR 114, VEGP LAR 16-012, Amendment 062/062, Dec 29, 2016, ADS Stage 2, 3, 4 Valve Flow Area

- WEC LAR 133, VEGP LAR 17-009, Amendment 111/110, Feb 28, 2018, Line Resistance

- WEC LAR 165, VEGP LAR 17-022, Amendment 104/103, Dec 20, 2017, LTOP Relief Valves

- WEC LAR 166, VEGP LAR 17-027, Amendment 118/117, Mar 29, 2018, Vacuum Fill Operations

- WEC LAR 202, VEGP LAR 18-009, Amendment 146/145, Oct 12, 2018, MODE 5&6 OPERABILITY 4

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Background Information (cont.)

Design Input DCD R.19 Baseline (2002)*

(2011)

License Date CRR SBLOCA LAR-06 LAR-80 (2008) (2018)

(2016) (2019)

DCD R.15 DCD R.17 (2002) (2002)

(2005) (2008)

Analysis reconciled Core Reference Certified design to final detailed Report PAST design CURRENT UNDERWAY 5

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 1 - ADS Stage 1 Max Stroke Time Updates 6

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 1 - ADS Stage 1 Max Stroke Time Updates

It was identified that the safety-related 4-inch ADS Stage 1 control valves (RCS-PL-V001A/B) may not meet design specification requirements at elevated design temperatures

Update proposed for the maximum stroke time of the ADS Stage 1 control valves to meet valve operability for design basis events

- ITAAC Impact

Propose to change ADS Stage 1 control valves maximum open/close time from 40 seconds to 48 seconds

- Includes changing the gear ratio with new gear sets

- Includes changing the limit switch setting

48 seconds is consistent with the updated stroke time modeled in the UFSAR Chapter 15 SBLOCA analysis (Change 3) 7

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 1 - ADS Stage 1 Max Stroke Time Updates (cont.)

CLB Impact - Tier 1 & TS Bases Licensing Basis Impact - Tier 2

ITAAC Table 2.1.2-4

UFSAR Table 14.3-2

- No. 2.1.02.11a.ii

UFSAR Table 15.6.5-10

TS Bases 3.4.11 Proposed markups of ITAAC Table 2.1.2-4 and UFSAR Table 15.6.5-10 shown 8

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 2 - ADS Stages 2&3 Max Stroke Times and Effective Flow Areas Updates 9

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 2 - ADS Stages 2&3 Max Stroke Times and Effective Flow Areas Updates

Updates proposed for the effective flow areas and max stroke times of the ADS Stages 2&3 globe valves based on the expected operating conditions - ITAAC Impact

ADS Stages 2&3 valves are important to the UFSAR Chapter 15 safety analysis to allow the RCS to depressurize sufficiently for ADS Stage 4 actuation and subsequent IRWST injection

- SBLOCA analyses model a minimum ADS flow area along with a maximum stroke time

LBLOCA and LOCA containment analyses do not model ADS Stages 2&3 valves

- No impact on these analyses

Non-LOCA inadvertent ADS/RCS depressurization analysis is limited by a larger effective flow area (max valve area) and a minimum stroke time

- No impact on non-LOCA analyses 10

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 2 - ADS Stages 2&3 Max Stroke Times and Effective Flow Areas Updates (cont.)

Current effective flow area calculated with equations applicable for liquid service (i.e., incompressible fluid)

- These valves are to be installed in the steam space of the pressurizer and will see either subcooled liquid (which flashes to a two-phase mixture) or saturated steam (i.e., compressible flow)

New testing has been performed to determine the effective flow area with compressible flow

- Testing performed in accordance with ANSI/ISA-75.02.01-2008 for compressible flow 11

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 2 - ADS Stages 2&3 Max Stroke Times and Effective Flow Areas Updates (cont.)

Test data shows an effective flow area of ~18.5 in2 at 100%

of the valve stroke

- This is below the current minimum effective flow are of 19 in2

Change proposes to reduce the minimum valve effective flow area to 16 in2

- 16 in2 is based on effective flow area at an intermediate stroke length with additional margin as the valves are required to be short-stroked to address the faster opening

Change proposes to increase the maximum stroke time from 100 seconds to 120 seconds

- Increase in maximum stroke time allows for a larger effective flow area, which is a benefit for depressurization 12

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 2 - ADS Stages 2&3 Max Stroke Times and Effective Flow Areas Updates (cont.)

Proposed markup of ITAAC Table 2.1.2-4, ITAAC No. 2.1.02.08d.iv shown 13

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 2 - ADS Stages 2&3 Max Stroke Times and Effective Flow Areas Updates (cont.)

Proposed markup of ITAAC Table 2.1.2-4, ITAAC No. 2.1.02.11a.ii shown 14

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 3 - SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA Analyses Updates 15

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 3 - SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA Analyses Updates

Design debt since 2008 requires update to the safety analyses and the corresponding CLB sections

- WEC LAR-080 will focus on SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA analyses updates

- Analysis updates due to input (no methodology changes)

- 10 CFR 50.46 peak cladding temperature (PCT) summary for SBLOCA will be cleared

- ADS Stages 1/2/3 max stroke time and ADS Stages 2/3 min effective flow area updates from Change 1 and Change 2 are incorporated

- Compliance with Tier 2* entrainment study is maintained

No impact to Tier 2* material in WEC LAR-080 16

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 3 - SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA Analyses Updates (cont.)

SBLOCA Analysis Update

Examines the plant response to:

- Inadvertent automatic depressurization system actuation (INADS) inch and 10-inch cold leg breaks

- Double-ended direct vessel injection (DEDVI) line breaks

SBLOCA-specific UFSAR text, tables, and figures are updated (Subsection 15.6.5.4B)

- No impacts or changes to the Tier 2* information are required

Updates to the SBLOCA analyses demonstrate ECCS continues to meet the 10 CFR 50.46 acceptance criteria

- Resultant PCT from limiting INADS transient is 1099°F

- Increase of +3°F from CLB PCT summary (1096°F) from latest 50.46 30-day report (WEC LAR-079, SNC LAR-17-043, Am.

147/146, approved Nov 07, 2018)

Limiting PCT still shows significant margin to 10 CFR 50.46 PCT limit 17

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 3 - SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA Analyses Updates (cont.)

Post-LOCA LTCC Analysis Update

Examines the plant response to:

- DEDVI break LTCC continuous calculation from IRWST injection through sump recirculation (Subsection 15.6.5.4C.2) day wall-to-wall floodup case (Subsection 15.6.5.4C.3)

Analysis updated to incorporate design debt since 2008

- Requires update to the corresponding CLB sections

Updates to the LTCC transient cases demonstrates:

- Continuous post-LOCA decay heat removal, as required by 10 CFR 50.46

- No fuel rod heatup during the transient 18

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 3 - SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA Analyses Updates (cont.)

Loss of RNS Analysis Update

Examines plant response to the loss of RNS cooling transient during shutdown conditions (Subsections 19E.4.8.2 and 19E.4.8.3)

Analysis updated to incorporate design debt since 2008

- Requires update to the corresponding CLB sections

Analysis demonstrates that a loss of shutdown cooling does not compromise the integrity of the fuel

- Active fuel region remains covered by a two-phase mixture for the duration of the event 19

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 3 - SBLOCA, LTCC, Loss of RNS, and Mode 3 LBLOCA Analyses Updates (cont.)

Mode 3 LBLOCA Analysis Update

Examines the plant response to confirm that the ECCS will perform adequately following a LBLOCA during plant shutdown conditions

Analysis updated to incorporate design debt since 2008

- Requires update to the corresponding CLB sections (primarily Subsection 19E.4.8.1)

Updates to the Mode 3 LBLOCA analysis demonstrates:

- Calculated PCT does not exceed 2200°F

- Max cladding oxidation remains below 17%

- Core-wide oxidation remains below 1%

20

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 4 - CMT TS Minimum Volume Updates 21

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)

Change 4 - CMT TS Minimum Volume Updates

VEGP Units 3&4 TS SR 3.5.2.2 requires borated water volume in each CMT be at least 2487 ft3

Based on as-built CMT dimensions, tank level associated with this volume correlates to approximately 99% of wide range level instrumentation span

Satisfying TS SR 3.5.2.2 would require instrument uncertainty & error to be less than 1% of span such that indicated level of 100% cannot be less than 99% measured tank level

- Based on uncertainty calculations, achieving this level of accuracy is not practical

Change to VEGP Units 3&4 TS proposed to resolve issue 22

- - This record was final approved on 5/16/2019 10:42:28 AM. (This statement was added by the PRIME system upon its validation)