ML17115A197
| ML17115A197 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 04/24/2017 |
| From: | Nextera Energy |
| To: | Mahesh Chawla Plant Licensing Branch III |
| Chawla M | |
| References | |
| Download: ML17115A197 (3) | |
Text
NG-17-XXXX Attachment 1 Page 2 of 7 2.2 Variations NextEra is proposing the following variations from the TS changes described in TSTF-542 or the applicable parts of the NRC staffs safety evaluation. These variations do not affect the applicability of TSTF-542 or the NRC staff's safety evaluation to the proposed license amendment.
- a. The Duane Arnold TS utilize different numbering and titles than the Standard TS on which TSTF-542 was based. The table below shows the differences between the plant-specific TS numbering and titles and the TSTF-542 numbering and titles. These differences are administrative and do not affect the applicability of TSTF-542 to the Duane Arnold TS.
TSTF-542 TS Numbering and Titles Duane Arnold TS Numbering and Titles TS 3.3.7.1 [ Main Control Room TS 3.3.7.1 Standby Filer Unit (SFU) System Environmental Control (MCREC) ] Instrumentation System Instrumentation TS 3.6.4.2 TS 3.7.4 Secondary Containment Isolation Valves (SCIVs)
[ Main Control Room Environmental Control (MCREC) ]
T TS 3.6.4.2 Secondary Containment Isolation TS 3.7.4 Valves/Dampers(SCIV/Ds)
Standby Filter Unit (SFU) System TS 3.7.5 TS 3.8.10 System (AC) ] System AF
[ Control Room Air Conditioning Distribution Systems - Shutdown TS 3.7.5 TS 3.8.8 Control Building Chiller (CBC)
System Distribution Systems - Shutdown
- b. In the Duane Arnold TS, the Note regarding realignment to the Low Pressure Coolant R
Injection mode is associated with SR 3.5.2.4 rather than LCO 3.5.2. This difference has no effect on the adoption of TSTF-542 and is an acceptable difference.
- c. TSTF-542 and the associated safety evaluation discuss the applicable regulatory requirements D
and guidance, including the 10 CFR 50, Appendix A, General Design Criteria (GDC).
Duane Arnold was not licensed to the 10 CFR 50, Appendix A, GDC. The Duane Arnold Updated Final Safety Analysis Report, section 3.1, contains an evaluation of the Duane Arnold design basis as measured against the AEC General Design Criteria (GDC) for nuclear power plants, Appendix A, of 10 CFR 50 effective May 21, 1971, and subsequently amended July 7, 1971. This difference does not alter the conclusion that the proposed change is applicable to Duane Arnold.
- d. The Duane Arnold TS contain a Surveillance Frequency Control Program. Therefore, the Surveillance Requirement Frequencies for Specification 3.5.2 are "In accordance with the Surveillance Frequency Control Program."
- e. Duane Arnold TS 3.6.1.3, PCIVs, is currently applicable in Modes 1, 2, and 3, and Modes 4 and 5 for the shutdown cooling system isolation valves when required by LCO 3.3.6.1, Primary Containment Isolation Instrumentation. However, TSTF-542 deletes from Table 3.3.6.1-1 the Modes 4 and 5 requirement for shutdown cooling system isolation. As a result,
NG-17-XXXX Attachment 1 Page 3 of 7 TS 3.6.1.3 will no longer require any PCIVs to be operable in Modes 4 or 5. Therefore, NextEra proposes to revise the Applicability to Modes 1, 2, and 3 and delete LCO Condition G, which is applicable in Modes 4 and 5, and the associated Required Actions from TS 3.6.1.3. In addition, the unnecessary reference to Modes 1, 2, or 3 in Condition F is deleted since LCO 3.6.1.3 is applicable only in Modes 1, 2 and 3. These changes are administrative in nature and are justified on the basis that TSTF-542 removed the Mode 4 and 5 Applicability from LCO 3.6.1.3.
- f. Duane Arnold does not have the capability to perform channel checks for the following functions in proposed Table 3.3.5.2-1, RPV Water Inventory Control Instrumentation:
Function 1.a, Reactor Steam Dome Pressure - Low (Injection Permissive), Function 1.b, Core Spray Pump Discharge Flow - Low (Bypass), Function 2.a, Reactor Steam Dome Pressure - Low (Injection Permissive), and Function 2.b, Low Pressure Coolant Injection Pump Discharge Flow - Low (Bypass). The current TS do not include channel checks for these functions and similarly, channel checks are not included for these functions in proposed Table 3.3.5.2-1.
T
- g. The Duane Arnold LPCI system consists of two loops with two pumps in each loop.
Function 2.f, Low Pressure Coolant Injection Pump Discharge Flow - Low (Bypass), in current TS Table 3.3.5.1-1 requires one operable channel per loop. NextEra proposes to only one flow instrument.AF include the one channel per loop requirement for Function 2.b in proposed Table 3.3.5.2-1 rather than one channel per pump as included in TSTF-542 because each LPCI loop has
- h. Duane Arnold current TS 3.6.4.1, Secondary Containment, and TS 3.6.4.3, Standby Gas Treatment System, are applicable in Modes 1, 2, and 3, and during OPDRVs. Consistent R
with TSTF-542, the applicability during OPDRVs is removed, so the TS applicability becomes Modes 1, 2, and 3. Condition A in TS 3.6.4.1 and Conditions B and D in TS 3.6.4.3 apply to conditions that occur in Modes 1, 2, and 3; e.g., secondary containment inoperable in Mode 1, 2, or 3. Since the applicability of these TS is changed to Modes 1, 2, i.
D and 3, it is no longer necessary for the Conditions to repeat the applicability. Therefore, NextEra proposes to remove the words in MODE 1, 2, or 3 from Condition A in TS 3.6.4.1 and Conditions B and D in TS 3.6.4.3. This is an administrative change that does not affect the applicability of TSTF-542 to the Duane Arnold TS.
Duane Arnold TS Table 3.3.5.1-1, Emergency Core Cooling System Instrumentation, does not include functions for manual initiation of CS and LPCI. Since the design does not include this feature, proposed Table 3.3.5.2-1 does not include manual initiation functions for CS and LPCI. In addition, TS 3.3.5.2 does not include a surveillance requirement (SR) for a logic system functional test since the SR applies only to the manual initiation function.
Likewise, the changes to TS 3.5.2, RPV Water Inventory Control, do not include SR 3.5.2.8, which demonstrates ECCS injection/spray actuation on a manual initiation signal.
NG-17-XXXX Attachment 1 Page 4 of 7
- j. LCO 3.3.6.1 currently requires Shutdown Cooling System (SDC) Isolation on reactor vessel water level-low in Modes 3, 4, and 5. TSTF-542 deletes the Modes 4 and 5 requirement for this function and includes this function in new TS 3.3.5.2 with an Applicability of When automatic isolation of the associated penetration flow path(s) is credited in calculating DRAIN TIME. The TS 3.3.6.1 Applicability of Mode 3 is retained to prevent this potential flow path from lowering the reactor vessel level to the top of the fuel in Mode 3. The current TS 3.3.6.1 Required Action for an inoperable channel is J.1, immediately initiate action to restore the channel to operable status; or J.2, immediately initiate action to isolate the Residual Heat Removal (RHR) Shutdown Cooling System. TSTF-542 deletes Required Action J.2; however, NextEra proposes to retain Required Action J.2 to account for SDC system isolation in Mode 3.
The Duane Arnold TS contain requirements that differ from the Standard Technical Specifications on which TSTF-542 was based, but are encompassed in the TSTF-542 justification:
- There are Duane Arnold specific instrumentation functions that differ from the Standard Technical Specifications (STS). Duane Arnold TS Table 3.3.5.1-1 includes Functions 1.f and T
2.k, 4.16 kV emergency bus sequential loading relay for the core spray (CS) and low-pressure coolant injection (LPCI) systems. These functions withhold the start permissive signal from the circuits that start the CS and LPCI pumps during accident conditions if an undervoltage AF condition exists on an emergency bus. These functions are unnecessary for manual operation; therefore, these functions can be removed from the TS because the required ECCS subsystem is proposed to be started by manual operation.
Duane Arnold TS Table 3.3.5.1-1 also includes Function 1.e, Core Spray Pump Start Time Delay Relay. The purpose of the time delay relay is to stagger the start of the CS pumps to limit the transient on the 4.16 kV emergency buses, similar to the purpose of the LPCI time R
delay relays in STS Table 3.3.5.1-1, Function 2.f. Changes to this instrumentation function are justified by the discussion in Section 3.4.1 of the TSTF-542 justification. This staggering is unnecessary for manual operation; therefore, the requirement for this function in Modes 4 and 5 can be removed from the TS.
D
3.0 REGULATORY ANALYSIS
3.1 No Significant Hazards Consideration Analysis NextEra Energy Duane Arnold, LLC (NextEra) requests adoption of TSTF-542 "Reactor Pressure Vessel Water Inventory Control," which is an approved change to the Standard Technical Specifications (STS), into the Duane Arnold Technical Specifications (TS). The proposed amendment replaces the existing requirements in the TS related to "operations with a potential for draining the reactor vessel" (OPDRVs) with new requirements on Reactor Pressure Vessel Water Inventory Control (RPV WIC) to protect Safety Limit 2.1.1.3. Safety Limit 2.1.1.3 requires reactor vessel water level to be greater than the top of active irradiated fuel.