ML19051A138

Attachment 2: Evaluation of Proposed Emergency Action Levels

ML19051A138
Person / Time
Site:	Callaway
Issue date:	02/20/2019
From:	Ameren Missouri, Union Electric Co
To:	Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation
Shared Package
ML17051A135	List: ML19051A138
References
ULNRC-06488
Download: ML19051A138 (10)

Text

Attachment 2 to ULNRC-06488 Evaluation of Proposed Emergency Action Levels (9 pages)

Evaluation of Proposed Emergency ActiGn Levels Page I

1.0 DESCRIPTION

In accordance with the provisions of Pali 50) Appendix E, section IV, item B, paragraph 2 and 50.90 of Title 10 of the Code of Federal Regulations (10 CFR), Union Etectric Company (Ameren Missouri),

is proposing changes to the emergency action lev els (EALs) and their technical bases, as used at Callaway Plant.

Ameren Missouri proposes to modify EALs CA6. l , "Cold Shutdown / Refueling System Malfunction

- Hazardous event affecting a SAFETY SYSTEM needed for the cutTent operating MODE: Ale1i,"

and SA9.l , "System Malfunction - Hazardous event affecting a SAFETY SYSTEM needed for the cunent operating MODE: Alert," and eliminate initiating condition (IC) HG I and associated EAL HGl.l , "Hazard - HOSTILE ACTION resulting in loss of physical control of the facility: General Emergency." Consistent with those changes, Ameren Missomi also proposes to re-define the term VISIBLE DAMAGE. Such changes to the EAL scheme require NRC approval prior to in1plementation. With these changes incorporated, the Emergency Plan for Call.away Plant would continue to meet the standards in 10 CFR 50.47(b) and the requirements in Appendix E to 10 CFR 50.

2.0 PROPOSED CHANGE

A brief description of the prnposed EAL changes is provided below along with a discussion of the justification for each change.

1. Change the verbiage in the EAL matrix and technical bases for EAL CA6.1 which reads:

The occwTence of any Table C-6 hazardous event.

AND EITHER:

• Event damage has caused indications of degraded perfonuance in at least one h*ain of a SAFETY SYSTEM needed for the current operating MODE.

• The event has caused VISIBLE DAMAGE to a SAFETY SYSTEM component or strnctureneeded for the current operating MODE.

to read:

The occuITence of any Table C-6 hazardous event AND Event damage has caused indications of degraded performance on one train of a SAFETY SYSTEM needed for the cunent operating MODE AND EITHER:

• Event damage has caused indications of degraded perfonnance in a second lrain of a SAFETY SYSTEM needed for the cunent operating MODE.

• Event damage has r,esuJted in VISIBLE DAMAGE to a second train of a SAFETY SYSTEM needed for the cunent operating MODE.

2 . Add Note 11 and Note 12 to the EAL Matrix (in the Notes text box and in the CA6. l EAL desc1iption text) per Emergency Preparedness Fi'equently Asked Question (EPFAQ) 2016-002, nclarification ofEquipment Damage as a Result of a Hazardous Event" :

Evaluation of Proposed Emergency Action Levels Page- 2 Note 11 : lf the affected SAFETY SYSTEM train was already inoperable or out of. service before the hazardous ~vent occuned, then this emergency classification is not wananted.

Note 12 : If the hazardous event only results in VISIBLE DAMAGE, with no indication of degraded pe1fo1mance to at least one train of a SAFETY SYSTEM, then this emergency classification is not wan-anted.

3 . Change the verbiage in the EAL matrix and technical bases for EAL SA9. l which reads:

The occmTence of any Table S-5 hazardous event.

AND EITHER:

• Event damage has caused indications of degraded perfo1mance in at least one train of a SAFETY SYSTEM needed for the cunent operating MODE.

• The event has caused VISIBLE DAMAGE to a SAFETY SYSTEM component or stmcture needed for the cun-eut operating MODE .

to read:

The occun-ence of any Table S-5 hazardous event AND Event damage has caused indications of degraded performance on one ,train of a SAFETY SYSTEM .needed for the current operating MODE AND EITHER:

• Event damage has caused i.odications of degraded perfonnance in a second train of a SAFETY SYSTEM needed for the current operating MODE.

• Event damage has resulted in VISIBLE DAMAGE to a second trai.o of a SAFETY SYSTEM needed for the cunent operating MODE.

4. Add Note 11 and Note 12 to the EAL Matrix (in the Notes text box and in the SA9, 1 EAL description text) per Emergency Preparedness Frequently Asked Question (EPP AQ) 2016-002, "Clatification of Equipment Damage as a Result of a if-Ia.zardous Event":

Note 11 : lf the affected SAFETY SYSTEM trnin was already inoperable or out of se1vice before the hazardous* event occtmed, then this emergency classification is not wananted .

Note 12 : If the hazardous event only results 'i n VISIBLE DAMAGE with no i.odication of degraded performance to at least one train of a SAFETY SYSTEM, then th.is emergency classification is not wa1Tanted.

5. Change the verbiage in the EAL technical bases document definition of VISIBLE DAMAGE, which reads:

Damage to a component or structure that is readily observable without measurements, testing or analysis. The visual impact of the damage is sufficient to cause concern tegardi.og the operability or reliability of tbe affected component or structure.

Evaluation of Proposed Emergency Action Levels Page 3 to read:

Damage to a SAFETY SYSTEM train that is readi1y observable without measurements, testing or analysis . The visual impact of the damage is sufficient to cause concern regarding the operability or reliability of the affected SAFETY SYSTEM train.

6. Remove EAL HG 1.1 and its associated IC HGl from the EAL Matrix per EPFAQ 2015-0013 "Hostile Action resulting in a loss of control of the facility declarations when fuel damage is likely within 4-hours or results in a loss of physical control of spent fuel" (and shade the resulting empty space in with gray shading to match the other gray shading on the wallcharts).

Also remove EAL HG 1.1 and IC HGl from the EAL Technical Bases Document, and eliminate references to EAL HG 1.1 and IC HGl from the technical bases for other EALs.

7. Add the following verbiage to EAL technical bases document regarding the Bases for EALs CA6. l and SA9 .1, consistent with the guidance that is provided in EPFAQ 2018-004, "EPFAQ 2018-04 Claii:fication of Hazardous Events and Safety Systems ConcwTence Package for Public Comment Release" :

An event affecting equipment common to two or more safety systems or safety system trains (i.e., there are indications of degraded performance and/or VISIBLE DAMAGE affecting the co~on equipment) should be classified as an Alert. :By affecting the operability or reliability of multiple system trains, the loss of the common equipment effectively meets the two-train impact criteria that underlie the EALs and Bases. For example, this guidance would apply to a unit with a tank that is the water source for multiple safety injection systems or trains, such as a Refueling Water Storage Tank.

An event that affects two trains of a safety system (e. g., one train bas indications of degraded petformance and the other VISIBLE DAMAGE) that also has one or more additional trains should be classified as an Alert. This approach maintains consistency with the r.vo-Lrain impact c1i.teria that underlie the EALs and Bases, and is wananted because the event was severe enough to affect the operability or reliability of two trains of a safety system despite plant desigp_ criteria associated with system and system train separation and protection. Such an ev ent may have caused other plant impacts that are not immediately apparent. For example, this gurda:nce would apply to a unit th.at has an Auxiliary/Emergency Feedwater System with three trains.

Regarding the changes listed as I, 2, 3, and 4 above, the wording ofEALs CA6 . l and SA9 .1 is being revised (and Notes 11 and 12 are being added) in order to precludec1n unnecessary Alert declaration when the hazardous event has not caused indication of degraded performance or visible daqrnge on a second train of the same safety system.

Regarding the change listed as 5 above, the definition of VISIBLE DAMAGE is being changed t work more seamlessly with modified EALs CA6.l and SA9 .1 (including added Note 12) described above.

Evaluation of Proposed Emergency Action Levels Page 4 Regarding the change listed as 6 above, EAL HG 1.1 (with its associated IC HGl) is redundant to other EALs, (i.e., RA2.1, RA2.2, RA2.3, RS2.l, RG2.1 , RSI.I, RSl.2, RSl.3 , RGI.I, RGl.2, RGl.3 ,

HSI .1 , HS6.1 , HS7 .I, and HG7 .l), which would encompass any escalation from a Hostile Action.

Regarding the change list~d as 7 above, the additional paragraphs are being added to the Bases for EALs CA6. l and SA9.l in order to provide clarification on bow to apply the EAL criteria to cases where the event affects equipment common to two or more safety systems or safety system trains, or where the event affects two trains of a safety system having more than two trains.

Mark-ups of affected pages and a clean copy of the revised EAL Technical Bases Document are provided as Attachments 3 and 4 to the license amendment requesL

3.0 BACKGROUND

EALs are the plant-specific indications, conditions or instrnment readings that are utilized to classify emergency conditions defined in the Callaway Plant Radiological Emergency Respons© Plan (RERP).

In 2015, the NRC approved use of an EAL scheme for Callaway Plant that was developed in accordance with NEI 99-01 Revision 6, "Methodology for the Development of Emergency Action Levels for Non-Passive Reactors.

Regarding tbeNEI 99-01 , Revision 6 EALs, the NRC staff position documented in EPFAQ 2016-002 states in part that:

An Ale11 should be declared only when actual or potential perforn1ance issues with SAFETY SYSTEMS have occu1Ted as a result of a hazardous event.. The occu1Tence of a hazardous event wiJJ result in a Notification of Unusual Event (NOUE) classification at a minimum. In order to wairnnt escalation to the Alert classification, the hazardous event should cause indications of degraded pe1f01mance to one train of a SAFETY SYSTEM with either indications of degraded performance on the second SAFETY SYSTEM train or VISIBLE DAMAGE to the second SAFETY SYSTEM train, such that the operability or reliability of the second h*ain is a concern. In addition, escalation to the Ale1t classification should not occm if the damage from the hazardous event is linlited to a SAFETY SYSTEM that was inoperable, or out of service, prior to the event occuning. As such, the proposed guidance will reduce the potential of declai:ing an Ale1t when events are in progress that do not involve an actual or potential substantial degradation of the level of safety of the plant, i.e., does not cause significant concern with shutting down or cooling down the plant.

It should be noted that the verbiage of the proposed new Notes 11 and 12 per the changes listed as 2 and 4 above is taken directly from EPFAQ 20 I 6-002.

Regarding the change listed as 6 above, Ameren Missowi originally developed IC HGl and EAL HG 1. I in accordance with NEI 99-01, Revision 6. Since implementation, many questions have arisen that could not be clearly answered due to the wording of the IC and EAL. Fmthe1more, it bas been noted that if a Hostile Action were to occur and major safety fonctions were lost (or damage to the fue1 pool occ01Ted), any accident that could cause a concern for the health and safety of the ip:ublic would

Evaluation of Proposed Emergency Action Levels Page 5 be identified by one or more of the other existing EALs. In regards to this issue, the NRC staff position documented in EPFAQ 2015-013 states in pa1i that:

Consideration can be given to not include EAL HG 1 in a site-specific EAL scheme. However EALs AA2, AS2 , AG2, ASl , AGI , HSl , HS6, HS7, and HG7 shall be as provided in NET 99-01, Revision 6.

Consistent with this guidance, Ameren Missouri has developed and implemented NEI 99-01 Revision 6 ICs AA2, AS2, AG2, ASl , AG!, HSI HS6, HS7, andHG7, as endorsed bytbeNRC. In the CallawayRERP, the equivalentICs are RA2, RS2, RG2, RSI , RGI , HSI , HS6, HS?, and HG?,

respectively. EAL HGLl (and its associated IC HG 1), which is proposed to be removed from the Callaway RERP, is redundnnt to EALs RA2.l , RA2.2, RA2.3, RS2.1, RG2 . l , RS.1.1 , RS1.2, RS1.3, RGI.] , RGl.2, RGI.3, HSI.I HS6.l , HS7. l , and HG7.l , as these EALs would encompass any escalation from a Hostile Action.

Regarding the change listed as 7 above, in EPFAQ 2018-004, the NRC staff concluded that the verbiage in the fast paragraph desc1ibed an acceptable resolution of a case where the event affects equipment common to two or more safety systems or safety system trains. The NRC staff further concluded that the verbiage in the second paragraph described an acceptable Tesolution of a case where the event affects two trains of a safety system having more than two trains. Since the approved Callaway Plant EAL scheme uses the EAL identifiers CA6. l and SA9. l in place of the NEI 99-01 Rev. 6 EAL identifiers CA6 and SA9, respectively, the clause "under CA6 or SA9, a.s appropriate to the plant mode, 11 has been omitted from the first sentence of each paragraph. This deviation from the EPFAQ 2018-004 does not affect the intent of either paragraph, as EAL CA6 . J would continue to apply only to system malfwictioos during cold shutdown / refueling, while EAL SA9. l would continue to apply only to system malfunctions dmriog other operating modes. The sentence added at the end of each paragraph describes an example of equipment or a system (taken from the questions that am cited in EPFAQ 2018-004) to which the guidance in the paragraph may be applied. It should be noted that the EPFAQ 2018-004 guidance regarding an event that affects a safety system that bas only one train does not apply to Callaway Plant, and therefore, Ameren Missouri does not propose to add this guidance to the EAL CA6.l or SA9. l Bases.

4.0 TECHNICAL ANALYSIS

The proposed changes affect the Callaway Plant Radiological Emergency Response Plan (RERP) and otherwise do not alter requirements of the Operating License or the Technical Specifications. These changes do not alter any of the assumptions used in the safety analyses, nor do they cause any safety system parameters to exceed their acceptance limits. Therefore, the prnposed changes have no adverse effect on plant safety.

5.0 REGULATORY ANALYSIS

5.1 Applicable Regulatory Requirements / Crite1ia Per 10 CFR 50.54(q)(2):

Evaluation of Proposed Emergency Action Levels Page 6 A holder of a license under this pa1t, or a combined license under prut 52 of this chapter after the Commission makes tb_e finding under § 52.103(g) of this ohapter, sha 11 follow and maintain the effectiveness of an emergency plan that meets the requirements in appendix E to this pait and, for nuclear power rnactor licensees, the planning standards of§ 50.47(b).

10 CFR 50.47(b)(4) requires the emergency i-esponse plan to meet the following standard:

A standard emergency classification and action level scheme, the bases of which include facility system and effluent pru*ameters, is in use by the nuclear facility licensee, and State and local response plans call for reliance on information provided by facility licensees for determinations of minimum initial offsite response measures.

10 CFR 50.54(q)(4) states:

The changes to a licensee's emergency plan that reduce the effectiveness of the plan as defined in paragraph (q)(l)(iv) of ~his section may not be implemented without prior approval by the NRC. A bcensee desiring to make such a change after February 21, 2012 shall submit an application for an amendment to its license. In addition to the filing requirements of§§ 50.90 and 50.91 , the request must include all emergency plan pages affected by that change and must be accompanied by a forwarding letter identifying the change, the reason for the change, and the basis for concluding that the licensee's emergency plan, as revised, will continue to meet the requirements in appendix E to this pait and, for nuclear power reactor licensees, the planning standards of§ 50.47(b) .

As defined in 10 CFR 50.54(q)(l)(iv) :

Reduction in effectiveness means a change in an emergency plan that results in reducing the licensee's capability to perform an emergency planning function in the event of a radiological emergency.

The proposed changes listed as 1, 2 3, 4, and 5 above are consistent with the NRC staff position documented in EPFAQ 2016-002, and Ameren Missotui bas therefore concluded that the Emergency Plan for Callaway Plant would continue to meet the planning standards of 10 CFR 50.47(b) and the requirements in Appenilix E to 10 CFR 50. However, an emergency event classification based on NRC-end0rsed industry guidance in NEI 99-01 , Revisions 4, 5, and 6, as well as in NUMARC/NESP-007, could be different from a classification based on the revised EALs. Therefore, this proposed change is considered a "deviation" in accordance with Regulatory Issue Summary (RIS) 2003-18, Supplement 2, "Use of Nuclear Energy Institute (NEl) 99-01 , Methodology for Development of Emergency Action Levels," Revision 4*. Deviations are considered to be a Teduction in effectiveness and thus, prior NRC approval js required.

The proposed change listed as 6 above is consistent with the NRC staff position documented in EPP AQ 2015-013, and Ameren Missomi has therefore concluded that the Emergency Plan for Callaway Plant would continue to meet the planning standards of 10 CFR 50.47(b) and the requirements in Appendix E to 10 CfR50. However, this proposed change is also c011sidered a

Evaluation of Proposed Emergency Action Levels Page. 7 "deviation" in accordance with Regulatory RIS 2003-18 , Supplement 2, and thus, piior NRC approval is required.

The proposed change listed as 7 above is consistent with the NRC staff position documented in EPFAQ 2018-004 that applies to plants that have implemented the guidance of EPFAQ 2016-002 ..

Ameren Missouri has therefore concluded that the Emergency Plan for Callaway Plant would continue to meet the planning standards of 10 CFR 50.4 7(b) aud the requirements in Appendix E to l O CFR 50.

This proposed change is considered a "difference" in accordance with Regulatmy RIS 2003-18, Supplement 2, and thus, p1ior NRC approval would not be required. However, its application is contingent upon NRC approval of the proposed changes listed as 1, 2, 3, 4, and 5 above.

5.2 No Significant Hazards Consideration Ameren Missomi has evaluated whether or not a significant hazards consideration is involved with the proposed changes by focusing on the three standards set forth in 10 CFR 50.92 1 "Issuance of amendment," as discussed below:

1. Does the proposed amendment involve a sign(ficanr increase in the probability or consequences of an accident previously evaluated?

Response: No. The proposed changes to the Callaway Plant eme1;gency action levels do not impact the physical function of plant structures, systems or components (SSC) or the manner in which SSCs perf01m their design function. The proposed changes have no effect on accident initiators or precw-sors, nor do they alter design assumptions. The proposed changes do not alter or prevent the ability of SSCs to pe1fo1m their intended function to mitigate the consequences of an initiating event within assumed acceptance limits. No operating procedures or administrative controls that function to preve11t or mitigate postulated accidents as described in the FSAR are affected by the proposed changes . Therefore, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed amendment create th e possibility of a ne-i,11or different kind of accidentfJ-om any accident pre, io11sly evaluated?

Response: No. The proposed changes do not involve a physical alterntion of the plant (i.e., no new or different type of equipment will be installed, and no equipment will be removed), nor do the proposed changes involve a change in the method of plant operation. The proposed changes will not introduce failme modes that could Tesult in a new accident, nor do the changes alter assumptions made in the safety analysis. Therefore, the proposed change does not crnate the possibility of a new or different kind of accident from any accident previously evaluated.

3. Does the proposed amendment involve a sign(ficant reduction In a margin of safety?

Response: No. There is no change being made to safety analysis assumptions, safety limits, or limiting safety system settings that would adversely affect plant safety as a result of the proposed changes. There are no changes to setpoints or environmental conditions of any SSC or the manner in which any SSC is operated. Margins of safety are unaffected by the proposed changes. The

Evaluation of Proposed E01ergency Action Leve1s Page 8 applicable requireinents of 10 CFR 50.47 and 10 CFR 50, Appendix E will conti1me to be met.

Therefore, tbe proposed changes do not involve any reduction in a margin of safety.

Based on the above, Ameren Missouti concludes that the proposed amendment presents no significant hazards consideration under the standards set fmth in 10 CFR 50.92, and accordingly, a finding of "no significant hazards consideration" is justified.

6.0 ENVIRONMENTAL CONSIDERATION

S The proposed changes to tl1e emergency action levels maintain the environmental bounds of the cunent environmental assessment associated with the Callaway Plant Unit l. The proposed changes will not affect plant safety and will nor have an adverse effect on the probability of an accident occun-ing. The proposed changes do not involve (i) a significant hazards consideration, (ii) a significant change in the types or si,gnificant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Therefore, no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

7.0 PRECEDENTS The proposed changes listed as 1, 2, 3, 4, and 5 above are similar in nature to changes that were included in a license amendment request (LAR) for changes to Monticello Nuclear Generating Plant EALs that was submitted by Northeru States Power Company (Xcel Energy) on September 27, 2017 (ADAMS Accession No . MLl 7269A076).

The proposed changes listed .as 6 above are similar in nature to changes that were included in a LAR for changes to the Beaver Valley Power Station EALs that was submitted by First Energy Nuclear Operating Company on August 10, 2017 (ADAMS Accession No. MLI 7222A219).

Ameren MissoUJi is not aware of any similar LARs that have yet been approved by the NRC.

8.0 REFERENCES

1. EPFAQ 2016-002, "Clarification of Equipment Damage as a Result of a Hazardous Event" (ADAMS Accession No. MLl 7195A299)

2. EPFAQ 2015-013, "Hostile Action resulting in a loss of control of the facility declarations when fuel damage is likely within 4-bours or results in a loss of physical control of spent fuel" (ADAMS Accession No. ML16166A366)

3. EPFAQ 2018-004, "EPFAQ 2018-04 Clarification of Hazardous Events and Safety Systems Concun-ence Package for Public Comment Release" (ADAMS Accession No. :tv:lLl 8268A168)

4. NRC Regulatory Issue Summary 2005-02, Revision 1, "Cladfying the Process for Making Emergency Plan Changes" (ADAMS Accession No. MLI 00340545)

5. NEI 99-01 , Revision 6, "Methodology for the Development of Emergency Action Levels for Non-Passjve Reactors" (ADAMS Accession No. ML12326A805)

Evaluation of Proposed Emergency Action Levels Page 9

6. Regulatory Issue Summary 2003-18, Supplement 2 "Use of Nuclear Energy Institute (NEI) 99-01 , Methodology for Developmnt of Emergency Action Levels/' Revision 4 (ADAMS Accession No. ML051450482)

7. NUMARC/NESP-007, Rev. 2, "Methodology for Development of Emergency Action Levels" (ADAMS Accession No. ML041120174) 1