NG-12-0167, License Amendment Request (TSCR-135): Application for One-Time Technical Specification Change Regarding Core Spray Operability During Shutdown Section Affected: 3.3.5.1

License Amendment Request (TSCR-135): Application for One-Time Technical Specification Change Regarding Core Spray Operability During Shutdown Section Affected: 3.3.5.1

ML12122A212
Person / Time
Site:	Duane Arnold
Issue date:	05/01/2012
From:	Wells P NextEra Energy Duane Arnold
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
NG-12-0167, TSCR-135
Download: ML12122A212 (26)

Text

NEXTera M

ENERGY~

May 1,2012 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Duane Arnold Energy Center Docket No. 50-331 Renewed Op. License No. DPR-49

~

DUANE ARNOLD NG-12-0167 10 CFR 50.90 License Amendment Request (TSCR-135): Application for One-Time Technical Specification Change Regarding Core Spray Operability during Shutdown Section Affected: 3.3.5.1 Pursuant to 10 CFR 50.90, NextEra Energy Duane Arnold, LLC (hereafter NextEra Energy Duane Arnold) hereby requests a one-time revision to the Technical Specifications (TS) for the Duane Arnold Energy Center (DAEC).

The proposed amendment would revise the DAEC TS on a one-time basis by adding a note to TS Table 3.3.5.1-1, Function 1 d, Modes 4 and 5, specifying that Function 1 d is not required to be met during RFO 23 in Modes 4 and 5. provides a description of the proposed change. Attachment 2 provides the existing TS pages marked up to show the proposed change. Attachment 3 provides the new typed TS pages showing the proposed change. Attachment 4 provides the proposed TS Bases changes for information only.

NextEra Energy Duane Arnold requests NRC review and approval of the proposed license amendment by October 6, 2012. NextEra Energy Duane Arnold is requesting accelerated approval in less than 1 year due to the need for this TS amendment to support re-coating of the internal Suppression Chamber surface (outer shell walls) in Refueling Outage (RFO) 23 (currently scheduled to begin on October 6, 2012).

NextEra Energy Duane Arnold has a license renewal commitment for DAEC to re-coat the internal Suppression Chamber surface. During the upcoming Refuel Outage (RF023), NextEra Energy Duane Arnold plans to fulfill that commitment.

Prior to the discovery of the need for this amendment request, NextEra Energy NextEra Energy Duane Arnold, LLC, 3277 DAEC Road, Palo, IA 52324

Document Control Desk NG-12-0167 May 1,2012 Page 2 of 3 Duane Arnold had already planned and obtained vendor contracts to perform the Suppression Chamber re-coating in RFO 23. Therefore, the upcoming RFO 23 is the only practical planned outage where NextEra Energy Duane Arnold can fulfill this commitment. Further information on the reasons for this request is provided in.

NextEra Energy Duane Arnold is requesting a 30 day implementation period to implement this license amendment.

This application has been reviewed by the DAEC Onsite Review Group. A copy of this submittal, along with the 10 CFR 50.92 evaluation of "No Significant Hazards Consideration," is being forwarded to our appointed state official pursuant to 10 CFR 50.91.

The following commitment is made in this amendment request:

NextEra Energy Duane Arnold will guard both CS subsystems and will not perform any work or testing on either of the CS subsystems during RFO 23 when both CS subsystems are needed to be Operable to meet the requirements of LCO 3.5.2.

If you have any questions or require additional information, please contact Steve Catron at 319-851-7234.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on May 1, 2012.

Peter Wells Vice President, Duane Arnold Energy Center NextEra Energy Duane Arnold, LLC Attachments: 1.

2.

3.

4.

5.

Description and Assessment Proposed Technical Specification Changes (Mark-ups)

Proposed Technical Specification Changes (Clean, typed)

Proposed Technical Specification Bases Changes (Mark-ups, for information only)

Commitment cc:

M. Rasmusson (State of Iowa) to NG-12-0167 Page 1 of 12 License Amendment Request (TSCR-135): Application for One-Time Technical Specification Change Regarding Core Spray Operability during Shutdown; Section Affected: 3.3.

5.1 DESCRIPTION

AND ASSESSMENT 1.0

SUMMARY

DESCRIPTION 2.0 DETAILED DESCRIPTION

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements 4.2 Precedent 4.3 No Significant Hazards Consideration 4.4 Conclusions

6.0 REFERENCES

to NG-12-0167 Page 2 of 12 1.0

SUMMARY

DESCRIPTION The proposed amendment would revise the DAEC TS on a one-time basis by adding a note to TS Table 3.3.5.1-1, Function 1d, Modes 4 and 5, specifying that Function 1d is not required to be met during RFO 23 in Modes 4 and 5.

NextEra Energy Duane Arnold requests NRC review and approval of the proposed license amendment by October 6, 2012.

2.0 DETAILED DESCRIPTION The proposed amendment would revise the DAEC TS on a one-time basis by adding a note to TS Table 3.3.5.1-1, Function 1d, Modes 4 and 5, specifying that Function 1d is not required to be met during RFO 23 in Modes 4 and 5.

NextEra Energy Duane Arnold has a license renewal commitment for DAEC to re-coat the internal Suppression Chamber surface. During the upcoming Refuel Outage (RFO23), NextEra Energy Duane Arnold plans to fulfill that commitment.

Prior to the discovery of the need for this amendment request, NextEra Energy Duane Arnold had already planned and obtained vendor contracts to perform the Suppression Chamber re-coating in RFO 23. Therefore, the upcoming RFO 23 is the only practical planned outage where NextEra Energy Duane Arnold can fulfill this commitment.

TS Bases associated with this change will be revised to describe the proposed TS change. Revised Bases pages are attached for information only and do not require NRC approval. The final TS Bases pages will be submitted with a future update in accordance with TS 5.5.10, "Technical Specifications (TS) Bases Control Program. It should be noted that Bases pages B3.3.5.1-109 and B3.5-21 have no changes associated with this amendment request, but are included for clarity.

TS SR 3.5.2.2 specifies the following must be performed on a Frequency determined by the Surveillance Frequency Control Program:

to NG-12-0167 Page 3 of 12 Verify, for each required Core Spray (CS) subsystem, the:

a.

Suppression pool water level is 8.0 ft; or

b.

---

NOTE-------------------------

Only one required CS subsystem may take credit for this option during OPDRVs. [Operations with the Potential for Draining the Reactor Vessel]

Condensate storage tank water level in one CST is 11 ft or 7 ft in both CSTs.

When suppression pool level is < 8.0 ft, the CS System is considered OPERABLE only if it can take suction from the Condensate Storage Tank (CST),

and the CST water level is sufficient to provide the required NPSH for the CS pump. Therefore, a verification that either the suppression pool water level is 8.0 ft or that CS is aligned to take suction from the CSTs and the CSTs contain 75,000 gallons of water, equivalent to 11 ft in one CST or 7 ft in both CSTs, ensures that the CS System can supply at least 75,000 gallons of makeup water to the RPV. However, as noted, only one required CS subsystem may take credit for the CST option during OPDRVs.

During OPDRVs, the volume in the CST may not provide adequate makeup if the Reactor Pressure Vessel (RPV) were completely drained. Therefore, only one CS subsystem is allowed to use the CST. This ensures the other required ECCS subsystem has adequate makeup volume.

During the Suppression Chamber re-coat project, all of the water will be removed from the Suppression Chamber, i.e., there will be no suppression pool available as an Emergency Core Cooling System (ECCS) suction source for a significant portion of this refueling outage. Because the Residual Heat Removal (RHR) system suction piping cannot be cross-tied to the CSTs, no RHR pumps will be available for satisfying LCO 3.5.2 whenever the Suppression Chamber is drained below the SR 3.5.2.1 requirements (Suppression Pool Level 7ft). Thus, in order to satisfy LCO 3.5.2 during its Applicability (MODE 4 and MODE 5, except when the cavity level is 21 ft, 1 inch above the RPV flange, with the Spent Fuel Pool gates removed), NextEra Energy Duane Arnold will need to rely exclusively on the CS subsystems for meeting LCO 3.5.2 when the Suppression Chamber is drained.

Additionally, during the Suppression Chamber re-coat project, it is necessary to isolate the CS minimum flow path to the Suppression Chamber to preclude draining of water from the CSTs to the Suppression Chamber during the re-coating process (i.e., the Suppression Chamber is completely drained to strip off to NG-12-0167 Page 4 of 12 the existing coating and to re-apply the new coating, including the curing process). The CS minimum flow valves are normally open valves and only close when CS flow > 600 gpm (nominal) is sensed. So, when the CS pump is not running, the minimum flow instruments send an open signal to the valves.

The current TS requires this minimum flow path to be available in order to maintain the CS subsystems Operable:

LCO 3.3.5.1 (ECCS Instrumentation) in Table 3.3.5.1-1, Function 1d, (Core Spray Pump Discharge Flow - Low (Bypass)) requires the CS minimum flow logic to be Operable whenever CS is required to be Operable per LCO 3.5.2 (see footnote a), and SR 3.5.2.4 also requires the minimum flow valve to be Operable.

Thus, during the Suppression Chamber re-coat process, i.e., with the suppression pool drained, and both CS subsystems aligned to the CSTs for suction with the minimum flow path secured, there would be no Operable ECCS subsystems. It should be noted that while both CS subsystems would be declared inoperable, they would be fully functional for injection during this time period.

Therefore, NextEra Energy Duane Arnold requests the following TS change on a one-time basis:

A note is proposed to be added to Table 3.3.5.1-1, Function 1d, Modes 4 and 5, specifying the following:

This requirement is not required to be met during Refueling Outage (RFO) 23.

3.0 TECHNICAL EVALUATION

3.1 System Description

The CS System is composed of two independent subsystems. Each subsystem consists of a motor driven pump, a spray sparger above the core, and piping and valves to transfer water from the suppression pool to the sparger. The CS System is designed to provide cooling to the reactor core when reactor pressure is low. Upon receipt of an initiation signal, the CS pumps in both subsystems are automatically started approximately 5 seconds after AC power is available.

When the RPV pressure drops sufficiently, CS System flow to the RPV begins. A full flow test line is provided to route water from and to the suppression pool to allow on-line testing of the CS System without spraying water in the RPV.

to NG-12-0167 Page 5 of 12 The CS pumps are provided with minimum flow bypass lines, which discharge to the suppression pool. The valves in these lines automatically open to prevent pump damage due to overheating when other discharge line valves are closed.

The minimum flow instruments are provided to protect the associated low pressure ECCS pump(s) from overheating when the pump is operating and the associated injection valve is not fully open. The minimum flow line valves (normally open for the CS System) receive an open signal when low flow is sensed, and automatically close when the flow rate is adequate to protect the associated pump. The CS Pump Discharge Flow Low Function is assumed to be OPERABLE and capable of closing the minimum flow valves to ensure that the low pressure ECCS flow rates assumed during the transients and accidents analyzed in the Update Final Safety Analysis Report (UFSAR) are met. The core cooling function of the ECCS, along with the scram action of the RPS, ensures that the fuel peak cladding temperature remains below the limits of 10 CFR 50.46.

One flow switch per CS pump division is used to detect the associated subsystems' flow rates. The logic is arranged such that each flow switch causes its associated minimum flow valve to receive an open signal. The logic will close the minimum flow valve once the closure setpoint is exceeded. The Pump Discharge Flow Low Allowable Values are high enough to ensure that the pump flow rate is sufficient to protect the pump, yet low enough to ensure that the closure of the minimum flow valve is initiated to allow the assumed flow into the core. Each channel of Pump Discharge Flow Low Function (two CS channels, one per pump) is only required to be OPERABLE when the CS is required to be OPERABLE to ensure that no single instrument failure can preclude the CS function.

The purpose of the CS minimum flow logic and associated valve is to protect the pump during initial pump start-up. When the reactor is at normal operating conditions (MODE 1, 2 and 3), the reactor pressure is higher than the rating of the CS piping outboard of the injection valves. Thus, there is a low pressure permissive for opening the injection valves (See LCO 3.3.5.1, Table 3.3.5.1, Function 1c). Therefore, there could be some time between the initiation signal for CS pumps to start (LOCA signals) and reactor pressure decaying to below this low pressure injection valve permissive; hence, the need for the minimum flow path to preclude overheating the CS pumps without an available injection pathway (i.e., dead headed). Once the injection valves open, full flow to the Reactor is achieved and the minimum flow logic closes the minimum flow valve to direct all the available CS flow to the Reactor, as intended. See figure below:

to NG-12-0167 Page 6 of 12 CoreSpraySystemSimplifiedDiagram to NG-12-0167 Page 7 of 12 3.2 Operating Experience LER 266/01-005 dated January 28, 2002 from Point Beach (ML020560352)

(Reference 1) details misalignment between system design and Emergency Operating Procedures (EOPs). If the Auxiliary Feedwater System (AFWS) pump discharge or flow control valves were throttled closed with the minimum recirculation valve failed closed, it is possible that the AFW pumps could be placed in a condition of insufficient flow. This could result in pump damage in a short interval of time. The operators were trained on the significance of maintaining adequate AFW recirculation flow. However; early in the post reactor trip emergency operating procedures, the operators were directed to control AFWS flow without specific written guidance to maintain minimum AFW flow. It was postulated that the loss of instrument air together with a common operator response to high steam generator level or overcooling of the Reactor Coolant System (RCS) had some probability to result in failure of one or all of the AFWS pumps.

3.3 Technical Evaluation During MODEs 4 and 5, the Reactor is fully depressurized and the low pressure permissive ( 450 psig nominal) for the CS injection valves is always satisfied, i.e., there is virtually no time between the CS initiation signal (low-low-low reactor vessel water level 64" nominal) and injection valve opening. However, the CS pump starts will be delayed for approximately five (5) seconds (See LCO 3.3.5.1, Function 1e). The purpose of this time delay relay is to stagger the start of the CS pumps that are in each of Divisions 1 and 2, thus limiting the starting transients on the 4.16 kV emergency buses. Based on Inservice Testing (IST) data, the CS injection Motor Operated Valves (MOVs) have a reference stroke time of approximately eight (8) seconds.

Therefore, the injection MOVs will be substantially open prior to the CS pump start to allow full flow to the Reactor and the likelihood of dead heading the CS pump is essentially nil. Consequently, there is no functional need for the minimum flow logic and valve(s) to be Operable in these MODES as this pump start sequence poses no risk to pump overheating. With the minimum flow path secured (manual valves closed), there is no diversion of CS away from the Reactor.

Current operating procedure guidance is adequate to ensure the pump is protected from runout conditions. Specifically, plant procedures direct As RPV pressure lowers, throttle INBD INJECT MO-2117 [MO-2137] valve using handswitch HS-2117 [HS-2137] on 1C03 to maintain <3100 gpm. Plant procedures will need to be enhanced to ensure a CS pump flow path is to NG-12-0167 Page 8 of 12 established and flow verified to be 600 gpm immediately following CS initiation and maintained as such during pump operation. The manual startup / initiation procedure will need to be temporarily revised to open the INBD INJECT MO-2117 [MO-2137] prior to starting a CS pump in MODES 4 and 5 for RFO 23 only.

Direct indication for CS pump flow is available in Panel 1C03 (refer to the diagram on Page 6). Alternate indications for confirming CS pump flow is 600 gpm, such as min-flow valve position which will be available as long as the associated instrumentation remains in service, should be used. If a flow path and required flow rate can not be confirmed, the pump shall promptly be secured.

Short duration operation of a CS pump at pump shutoff head (i.e. dead headed),

sufficient for the Operators to diagnose the condition and secure the pump, is not detrimental to the pump. However, extended operation beyond a few minutes could cause pump damage.

Potential human errors of consequence that could result from this activity are:

1. CS Pump damage from prolonged low flow or dead head operation.

2. Diversion of CS injection flow through min-flow line as a result of failure to ensure the line is isolated.

Strict administrative and procedural controls, operator training, and use of human performance tools will be essential to preventing these types of consequential human errors. Furthermore, both CS subsystems will be guarded and no work or testing will be permitted on either of the CS subsystems during RFO 23 when both CS subsystems are needed to be Operable to meet the requirements of LCO 3.5.2.

NextEra Energy Duane Arnold also plans to comply with the requirements of EGM-11-003, Enforcement Guidance Memorandum on Dispositioning Boiling Water Reactor Licensee Noncompliance with Technical Specification Containment Requirements during OPDRVs (Reference 2).

Conclusion The proposed change and RFO23 strategy to maintain the Core Spray system Operable with the minimum flow line administratively isolated is acceptable and poses no unacceptable risk to nuclear safety or the reliability of the Core Spray system.

to NG-12-0167 Page 9 of 12

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements 10 CFR 50.36 requires in part that the operating license of a nuclear production facility include technical specifications. Paragraph (c)(2)(ii) of that part requires that a Limiting Condition For Operation (LCO) of a nuclear reactor must be established for each item meeting one or more of four criteria. ECCS Instrumentation identified in LCO 3.3.5.1 meets Criterion 3, "A structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier."

Paragraph (c)(3) further requires the establishment of Surveillance Requirements, "relating to test, calibration, or inspection to assure... that the limiting conditions for operation will be met." As discussed above, the proposed one-time change to add a note to TS Table 3.3.5.1-1, Function 1d, Modes 4 and 5, specifying that Function 1d is not required to be met during RFO 23 in Modes 4 and 5 is sufficient to demonstrate Operability of the CS System and therefore, are sufficient to ensure that the LCO is met.

4.2 Precedent None 4.3 No Significant Hazards Consideration Determination NextEra Energy Duane Arnold has evaluated whether or not a significant hazards consideration is involved with the proposed amendment(s) using the three standards set forth in 10 CFR 50.92, Issuance of amendment, as discussed below:

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

Response: No.

The proposed amendment would revise the DAEC TS on a one-time basis by adding a note to TS Table 3.3.5.1-1, Function 1d, Modes 4 and 5, specifying that Function 1d is not required to be met during RFO 23 in Modes 4 and 5.

Accidents are initiated by the malfunction of plant equipment, or the catastrophic failure of plant structures, systems, or components.

to NG-12-0167 Page 10 of 12 The low pressure Emergency Core Cooling System (ECCS) subsystems are designed to inject to reflood or to spray the core after any size break up to and including a design basis Loss of Coolant Accident (LOCA). The proposed change to the Core Spray System Operability requirements does not change the operating configurations or minimum amount of operating equipment assumed in the safety analysis for accident mitigation. The change does not require any change in safety analysis methods or results.

Also, it does not change the amount of core spray provided to the core in the accident analyses. No changes are proposed to the manner in which the ECCS provides plant protection or which would create new modes of plant operation. The proposed change does not result in any new or affect the probability of any accident initiators. There will be no degradation in the performance of, or an increase in the number of challenges imposed on, safety related equipment assumed to function during an accident situation.

There will be no change to normal plant operating parameters or accident mitigation performance. This change will only apply when the plant is in MODES 4 and 5 where LOCAs are not postulated to occur. In MODES 4 and 5, the CS function is to mitigate OPDRVS. Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

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

Response: No.

This change does not affect the method by which any plant systems perform a safety function. It does not introduce any new equipment, or hardware changes, which could create a new or different kind of accident. No new release pathways or equipment failure modes are created. No new accident scenarios failure mechanisms or limiting single failures are introduced as a result of this request. This request does not affect the normal methods of plant operation. The Core Spray System retains its ability to function following any accident previously evaluated and provide the proper flow rate to the core. This change will only apply when the plant is in MODES 4 and 5 where LOCAs are not postulated to occur. In MODES 4 and 5, the CS function is to mitigate OPDRVS. Strict administrative and procedural controls, operator training, and use of human performance tools will be essential to preventing these types of consequential human errors. Furthermore, both CS subsystems will be guarded and no work or testing will be permitted on either of the CS subsystems during RFO 23 when both CS subsystems are needed to be Operable to meet the requirements of LCO 3.5.2. Therefore, the implementation of the proposed change will not create a possibility for an accident of a new or different type than those previously evaluated.

to NG-12-0167 Page 11 of 12

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

Response: No.

The ECCS are designed with sufficient redundancy such that if a Core Spray subsystem were unavailable, or did not provide the required flowrate, the remaining Core Spray subsystem is capable of providing water and removing heat loads to satisfy the Updated Final Safety Analysis Report requirements for accident mitigation. A minimum of two low pressure ECCS subsystems continue to be required to be OPERABLE in MODES 4 and 5, except with the spent fuel storage pool gates removed and water level 21 ft 1 inch over the top of the reactor pressure vessel flange. There is no change in the Limiting Conditions for Operation. For these reasons, the proposed amendment does not involve a significant reduction in a margin of safety.

Based on the above, NextEra Energy Duane Arnold concludes 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 In conclusion, 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.

5.0 ENVIRONMENTAL CONSIDERATION

10 CFR Section 51.22(c)(9) identifies certain licensing and regulatory actions which are eligible for categorical exclusion from the requirement to perform an environmental assessment. A proposed amendment to an operating license for a facility requires no environmental assessment if operation of the facility in accordance with the proposed amendment would not: (1) involve a significant hazards consideration; (2) result in a significant change in the types or significant increase in the amounts of any effluents that may be released offsite; and (3) result in a significant increase in individual or cumulative occupational radiation exposure. NextEra Energy Duane Arnold has reviewed this request and determined that the proposed amendment meets the eligibility criteria for to NG-12-0167 Page 12 of 12 categorical exclusion set forth in 10 CFR Section 51.22(c)(9). Pursuant to 10 CFR Section 51.22(b), no environmental impact statement or environmental assessment needs to be prepared in connection with the issuance of the amendment. The basis for this determination follows:

Basis The change meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9) for the following reasons:

1. As demonstrated in the 10 CFR 50.92 evaluation included in Section 4.3, the proposed amendment does not involve a significant hazards consideration.

2. The proposed change does not result in an increase in power level, do not increase the production, nor alter the flow path or method of disposal of radioactive waste or byproducts. There is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite.

3. The proposed change does not result in changes in the level of control or methodology used for processing of radioactive effluents or handling of solid radioactive waste nor will the proposal result in any change in the normal radiation levels within the plant. There is no significant increase in individual or cumulative occupational radiation exposure.

6.0 REFERENCES

1. LER-266-2001-005, PRA Assessment of Auxiliary Feedwater System Reveals Procedural Vulnerability Related To Loss Of Instrument Air Point Beach Nuclear Plant, Units 1 And 2, dated January 28, 2002 (ML020560352)

2. EGM-11-003, Enforcement Guidance Memorandum on Dispositioning Boiling Water Reactor Licensee Noncompliance with Technical Specification Containment Requirements during Operations with a Potential for Draining the Reactor Vessel, October 4, 2011 to NG-12-0167 1 page follows TSCR-132 Technical Specification Page (Markups)

ECCS Instrumentation 3.3.5.1 DAEC 3.3-41 TSCR-135 Table 3.3.5.1-1 (page 1 of 5)

Emergency Core Cooling System Instrumentation FUNCTION APPLICABLE MODES OR OTHER SPECIFIED CONDITIONS REQUIRED CHANNELS PER FUNCTION CONDITIONS REFERENCED FROM REQUIRED ACTION A.1 SURVEILLANCE REQUIREMENTS ALLOWABLE VALUE

1. Core Spray System

a. Reactor Vessel Water Level - Low Low Low 1,2,3, 4(a), 5(a) 4(b)

B SR 3.3.5.1.1 SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 38.3 inches

b. Drywell Pressure -

High 1,2,3 4(b)

B SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

< 2.19 psig

c. Reactor Steam Dome Pressure - Low (Injection Permissive) 1,2,3 4(a), 5(a) 4 4

C B

SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9 SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 363.3 psig and < 485.1 psig

> 363.3 psig and < 485.1 psig

d. Core Spray Pump Discharge Flow - Low (Bypass) 1,2,3, 4(a)*, 5(a)*

1 per pump E

SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 256.6 gpm and

< 2382.1 gpm

e. Core Spray Pump Start Time Delay Relay 1,2,3, 4(a), 5(a) 1 per pump C

SR 3.3.5.1.8 SR 3.3.5.1.9

> 2.6 seconds and < 6.8 seconds

f. 4.16 kV Emergency Bus Sequential Loading Relay 1,2,3, 4(a), 5(a) 1 per pump F

SR 3.3.5.1.5 SR 3.3.5.1.6 SR 3.3.5.1.9

< 3500 V

2. Low Pressure Coolant Injection (LPCI) System

a. Reactor Vessel Water Level-Low Low Low 1,2,3, 4(a), 5(a) 4 B

SR 3.3.5.1.1 SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 38.3 inches

b. Drywell Pressure -

High 1,2,3 4

B SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

< 2.19 psig (continued)

(a) When associated ECCS subsystem(s) are required to be OPERABLE per LCO 3.5.2, ECCS-Shutdown.

(b) Also required to initiate the associated Diesel Generator (DG).

• This requirement is not required to be met during Refueling Outage (RFO) 23.

to NG-12-0167 1 page follows TSCR-132 Technical Specification Page (Clean typed)

ECCS Instrumentation 3.3.5.1 DAEC 3.3-41 Amendment Table 3.3.5.1-1 (page 1 of 5)

Emergency Core Cooling System Instrumentation FUNCTION APPLICABLE MODES OR OTHER SPECIFIED CONDITIONS REQUIRED CHANNELS PER FUNCTION CONDITIONS REFERENCED FROM REQUIRED ACTION A.1 SURVEILLANCE REQUIREMENTS ALLOWABLE VALUE

1. Core Spray System

a. Reactor Vessel Water Level - Low Low Low 1,2,3, 4(a), 5(a) 4(b)

B SR 3.3.5.1.1 SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 38.3 inches

b. Drywell Pressure -

High 1,2,3 4(b)

B SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

< 2.19 psig

c. Reactor Steam Dome Pressure - Low (Injection Permissive) 1,2,3 4(a), 5(a) 4 4

C B

SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9 SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 363.3 psig and < 485.1 psig

> 363.3 psig and < 485.1 psig

d. Core Spray Pump Discharge Flow - Low (Bypass) 1,2,3, 4(a)*, 5(a)*

1 per pump E

SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 256.6 gpm and

< 2382.1 gpm

e. Core Spray Pump Start Time Delay Relay 1,2,3, 4(a), 5(a) 1 per pump C

SR 3.3.5.1.8 SR 3.3.5.1.9

> 2.6 seconds and < 6.8 seconds

f. 4.16 kV Emergency Bus Sequential Loading Relay 1,2,3, 4(a), 5(a) 1 per pump F

SR 3.3.5.1.5 SR 3.3.5.1.6 SR 3.3.5.1.9

< 3500 V

2. Low Pressure Coolant Injection (LPCI) System

a. Reactor Vessel Water Level-Low Low Low 1,2,3, 4(a), 5(a) 4 B

SR 3.3.5.1.1 SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

> 38.3 inches

b. Drywell Pressure -

High 1,2,3 4

B SR 3.3.5.1.3 SR 3.3.5.1.8 SR 3.3.5.1.9

< 2.19 psig (continued)

(a) When associated ECCS subsystem(s) are required to be OPERABLE per LCO 3.5.2, ECCS-Shutdown.

(b) Also required to initiate the associated Diesel Generator (DG).

• This requirement is not required to be met during Refueling Outage (RFO) 23.

to NG-12-0167 5 pages follow TSCR-135 Technical Specification BASES pages (Markups)

FOR INFORMATION ONLY

ECCS Instrumentation B 3.3.5.1 (continued)

DAEC B 3.3-109 Amendment 223 BASES APPLICABLE SAFETY

ANALYSES, LCO, and APPLICABILITY 1.c, 2.c. Reactor Steam Dome Pressure Low (Injection Permissive) (continued)

Four channels of Reactor Steam Dome Pressure Low Function are only required to be OPERABLE when the ECCS is required to be OPERABLE to ensure that no single instrument failure can preclude ECCS initiation. Refer to LCO 3.5.1 and LCO 3.5.2 for Applicability Bases for the low pressure ECCS subsystems.

1.d, 2.f. Core Spray and Low Pressure Coolant Injection Pump Discharge Flow Low (Bypass)

The minimum flow instruments are provided to protect the associated low pressure ECCS pump(s) from overheating when the pump is operating and the associated injection valve is not fully open. The minimum flow line valves (normally open for the CS System and normally closed for the LPCI System) receive an open signal when low flow is sensed, and automatically close when the flow rate is adequate to protect the associated pump.

The LPCI and CS Pump Discharge Flow Low Functions are assumed to be OPERABLE and capable of closing the minimum flow valves to ensure that the low pressure ECCS flow rates assumed during the transients and accidents analyzed in References 1, 2, and 3 are met. The core cooling function of the ECCS, along with the scram action of the RPS, ensures that the fuel peak cladding temperature remains below the limits of 10 CFR 50.46.

One flow switch per CS pump and one differential pressure switch for the two RHR pumps in each division are used to detect the associated subsystems' flow rates. The logic is arranged such that each differential pressure switch or flow switch causes its associated minimum flow valve to receive an open signal. The logic will close the minimum flow valve once the closure setpoint is exceeded. The LPCI minimum flow valves are time delayed such that the valves will not open for 10 seconds after the switches detect low flow. The time delay is provided by design to limit reactor vessel inventory loss during the startup of the RHR shutdown cooling mode although, typically, the minimum flow valves are prevented from opening when operating in the shutdown cooling mode. The Pump Discharge Flow Low Allowable Values are high enough to ensure that the pump flow rate is sufficient to protect the pump, yet low enough to ensure

ECCS Instrumentation B 3.3.5.1 (continued)

DAEC B 3.3-110 TSCR-135 BASES APPLICABLE SAFETY

ANALYSES, LCO, and APPLICABILITY 1.d, 2.f. Core Spray and Low Pressure Coolant Injection Pump Discharge Flow-Low (Bypass) (continued) that the closure of the minimum flow valve is initiated to allow the assumed flow into the core. Each channel of Pump Discharge Flow Low Function (two CS channels, one per pump and two LPCI channels, one per loop) is only required to be OPERABLE when the associated ECCS is required to be OPERABLE to ensure that no single instrument failure can preclude the ECCS function. Refer to LCO 3.5.1 and LCO 3.5.2 for Applicability Bases for the low pressure ECCS subsystems.*

2.d. Reactor Vessel Shroud Level Low The Reactor Vessel Shroud Level-Low Function is provided as a permissive to allow the RHR System to be manually aligned from the LPCI mode to the suppression pool cooling/spray or drywell spray modes with a LPCI initiation signal still present. This function ensures: 1) that the permissive is removed prior to reaching two thirds core height when vessel level is decreasing, and 2) that the permissive is not restored until two thirds core height is reached when vessel level is increasing. This ensures that LPCI is available to prevent or minimize fuel damage. This function may be overridden during accident conditions as allowed by plant procedures to allow containment cooling/spray regardless of the level present in the shroud.

Reactor Vessel Shroud Level Low signals are initiated from four level transmitters that sense the difference between the pressure due to a constant column of water (reference leg) and the pressure due to the actual water level (variable leg) in the vessel. The Reactor Vessel Shroud Level Low Allowable Value is chosen to allow the low pressure core flooding systems to activate and provide adequate cooling before allowing a manual transfer.

Four channels of the Reactor Vessel Shroud Level Low Function are only required to be OPERABLE in MODES 1, 2, and 3. In MODES 4 and 5, the specified initiation time of the LPCI subsystems is not assumed, and other administrative controls are adequate to control the valves that this Function isolates (since the containment cooling mode of RHR is not required to be OPERABLE in MODES 4 and 5 and is normally not used).

• During Refueling Outage (RFO) 23, the CS minimum flow path is not required to be available for CS to be considered OPERABLE.

ECCS Shutdown B 3.5.2 (continued)

DAEC B 3.5-21 Amendment 223 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) AND REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM B 3.5.2 ECCS Shutdown BASES BACKGROUND A description of the Core Spray (CS) System is provided in the Bases for LCO 3.5.1, "ECCS-Operating".

The Low Pressure Coolant Injection (LPCI) Mode of the Residual Heat Removal (RHR) System, for the application of this specification, takes on a different definition than is described in the Bases for LCO 3.5.1 "ECCS-Operating". In the application of "ECCS-Shutdown", the low pressure ECCS subsystems consist of two CS subsystems and two LPCI subsystems. Each LPCI subsystem consists of one motor driven RHR pump, piping, and valves to transfer water from the suppression pool to the Reactor Pressure Vessel (RPV). Only a single RHR pump is required per subsystem because of the larger injection capacity in relation to a CS subsystem.

APPLICABLE SAFETY ANALYSES The ECCS performance is evaluated for the entire spectrum of break sizes for a postulated Loss of Coolant Accident (LOCA).

The long term cooling analysis following a design basis LOCA (Ref. 1) demonstrates that only one low pressure ECCS pump is required, post LOCA, to maintain adequate reactor vessel water level. It is reasonable to assume, based on engineering judgement, that while in MODES 4 and 5, one low pressure ECCS subsystem can maintain adequate reactor vessel water level. To provide redundancy, a minimum of two low pressure ECCS subsystems are required to be OPERABLE in MODES 4 and 5.

The low pressure ECCS subsystems satisfy Criterion 3 of 10 CFR 50.36(c)(2)(ii).

LCO Two low pressure ECCS subsystems are required to be OPERABLE. For this specification, the low pressure ECCS subsystems consist of two CS subsystems and two LPCI subsystems. Each CS subsystem consists of one motor driven pump, piping, and valves to transfer water from the suppression pool or Condensate Storage Tank (CST) to the Reactor Pressure

ECCS Shutdown B 3.5.2 (continued)

DAEC B 3.5-22 TSCR-135 BASES LCO (continued)

Vessel (RPV)*. Each LPCI subsystem consists of one motor driven RHR pump, piping, and valves to transfer water from the suppression pool to the RPV. Only a single RHR pump is required per subsystem because of the larger injection capacity in relation to a CS subsystem. In MODES 4 and 5, the RHR System cross tie valve is not required to be open. The necessary portions of Emergency Service Water are also required to provide appropriate cooling to each required CS subsystem. One LPCI subsystem may be aligned for decay heat removal and considered OPERABLE for the ECCS function, if it can be manually realigned (remote or local) to the LPCI mode and is not otherwise inoperable. Because of low pressure and low temperature conditions in MODES 4 and 5, sufficient time will be available to manually align and initiate LPCI subsystem operation to provide core cooling prior to postulated fuel uncovery.

APPLICABILITY OPERABILITY of the low pressure ECCS subsystems is required in MODES 4 and 5 to ensure adequate coolant inventory and sufficient heat removal capability for the irradiated fuel in the core in case of an inadvertent draindown of the vessel. Requirements for ECCS OPERABILITY during MODES 1, 2, and 3 are discussed in the Applicability section of the Bases for LCO 3.5.1.

ECCS subsystems are not required to be OPERABLE during MODE 5 with the spent fuel storage pool gates removed and the water level maintained at 21 ft 1 inch above the RPV flange.

This provides sufficient coolant inventory to allow operator action to terminate the inventory loss prior to fuel uncover in case of an inadvertent draindown.

The Automatic Depressurization System is not required to be OPERABLE during MODES 4 and 5 because the RPV pressure is 100 psig, and the CS and LPCI subsystems can provide core cooling without any depressurization of the primary system.

The High Pressure Coolant Injection System is not required to be OPERABLE during MODES 4 and 5 since the low pressure ECCS subsystems can provide sufficient flow to the vessel and because insufficient reactor pressure is available to drive the HPCI turbine.

• During Refueling Outage (RFO) 23, the CS minimum flow path is not required to be available for CS to be considered OPERABLE.

ECCS Shutdown B 3.5.2 (continued)

DAEC B 3.5-25 TSCR-135 BASES SURVEILLANCE REQUIREMENTS SR 3.5.2.1 and SR 3.5.2.2 (continued)

When suppression pool level is < 8.0 ft, the CS System is considered OPERABLE only if it can take suction from the CST, and the CST water level is sufficient to provide the required NPSH for the CS pump. Therefore, a verification that either the suppression pool water level is 8.0 ft or that CS is aligned to take suction from the CSTs and the CSTs contain 75,000 gallons of water, equivalent to 11 ft in one CST or 7 ft in both CSTs, ensures that the CS System can supply at least 75,000 gallons of makeup water to the RPV. However, as noted, only one required CS subsystem may take credit for the CST option during OPDRVs. During OPDRVs, the volume in the CST may not provide adequate makeup if the RPV were completely drained. Therefore, only one CS subsystem is allowed to use the CST. This ensures the other required ECCS subsystem has adequate makeup volume.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Frequency of these SRs was developed considering operating experience related to suppression pool water level and CST water level variations during the applicable MODES. Furthermore, the Frequency is considered adequate in view of other indications available in the control room to alert the operator to an abnormal suppression pool or CST water level condition.

SR 3.5.2.3, SR 3.5.2.5, and SR 3.5.2.6 The Bases provided for SR 3.5.1.1, SR 3.5.1.4, and SR 3.5.1.7 are applicable to SR 3.5.2.3, SR 3.5.2.5, and SR 3.5.2.6, respectively.

SR 3.5.2.4 Verifying the correct alignment for power operated and automatic valves in the ECCS flow paths provides assurance that the proper flow paths will exist for ECCS operation.* This SR does not apply to valves that are locked, sealed, or otherwise secured in position, since these valves were verified to be in the correct position prior to locking, sealing, or securing. A valve that receives an initiation signal is allowed to be in a nonaccident position provided the

• During Refueling Outage (RFO) 23, the CS minimum flow path is not required to be available for CS to be considered OPERABLE.

to NG-12-0167 Page 1 of 2 TSCR-135 Commitment to NG-12-0167 Page 2 of 2 Commitment

1.

NextEra Energy Duane Arnold will guard both CS subsystems and will not perform any work or testing on either of the CS subsystems during RFO 23 when both CS subsystems are needed to be Operable to meet the requirements of LCO 3.5.2.