ML17250A870

MNGP TSTF-542 Draft Variations

ML17250A870
Person / Time
Site:	Monticello
Issue date:	09/07/2017
From:	Robert Kuntz Plant Licensing Branch III
To:
Kuntz R, NRR/DORL/LPLIII
References
Download: ML17250A870 (5)

Text

2.2 Variations NSPM is proposing the following variations from the TS changes described in the 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 MNGP TS, in some cases, utilizes 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 editorial and do not affect the applicability of TSTF-542 to the MNGP TS.

NUREG-1433 Numbering and Titles MNGP TS Numbering and Titles TS 3.3.7.1

[ Main Control Room Environmental Control (MCREC) ] System Instrumentation TS 3.3.7.1 Control Room Emergency Filtration (CREF) System Instrumentation TS 3.5.2 Reactor Pressure Vessel (RPV) Water Inventory Control.

TS 3.5.2 RPV Water Inventory Control.

TS 3.7.4

[ Main Control Room Environmental Control (MCREC) ] System TS 3.7.4 Control Room Emergency Filtration (CREF) System TS 3.7.5

[ Control Room Air Conditioning (AC) ]

System TS 3.7.5 Control Room Ventilation System TS 3.8.8 Inverters - Shutdown None None TS 3.8.10 Distribution Systems -

Shutdown TS 3.8.8 Distribution Systems -

Shutdown

b. TSTF-542 and the associated safety evaluation discuss the applicable regulatory requirements and guidance, including the 10 CFR 50, Appendix A, General Design Criteria (GDC). MNGP was not licensed to the 10 CFR 50, Appendix A, GDC. The MNGP Updated Final Safety Analysis Report (UFSAR), Appendix E contains a comparative evaluation of the design basis of MNGP with respect to the 70 General Design Criteria for Nuclear Power Plant Construction Permits proposed by the Atomic Energy Commission for public comment in July, 1967.

This difference does not alter the conclusion that the proposed change is applicable to MNGP.

c. The MNGP TS include Amendment No. 189 (Reference 1) for TSTF-523, "Generic Letter 2008-01, Managing Gas Accumulation." The following changes have no effect on the adoption of TSTF-542 and are an acceptable variation:

• SR 3.5.2.2 has been modified from; Verify, for the required ECCS injection/spray subsystem, the piping is filled with water from the pump discharge valve to the injection valve," to; "Verify, for the required ECCS Draft

injection/spray subsystem, locations susceptible to gas accumulation are sufficiently filled with water.

• SR 3.5.2.3 has been modified to retain the NOTE, "Not required to be met for system vent flow paths opened under administrative control."

d. NSPM proposes to change the new Reactor Pressure Vessel (RPV) Water Inventory Control Instrumentation section to TS 3.3.5.3 for consistency purposes.

This change is editorial and does not affect the applicability of TSTF-542 to the MNGP TS.

e. The MNGP design does not include a Reactor Vessel Water Level - Low Low Low feature. The corresponding MNGP TS Table 3.3.5-1 functions 1.a and 2.a and TS Table 3.3.7-1 Function 1 occur on a Reactor Vessel Water Level - Low Low signal. Therefore, it is appropriate to revise MNGP TS Table 3.3.5.3.-1 and 3.3.7.1-1to reflect this design difference.

f. STS Table 3.3.5.1-1, Function 1.d, "Core Spray Pump Discharge Flow - Low (Bypass)" is not included in the MNGP TSs. The function is performed passively via a 2 1/2 inch bypass line with a restricting orifice and locked open manual isolation valve. As a result, this function is not being included in TS 3.3.5.3, "Reactor Pressure Vessel (RPV) Water Inventory Control," Table 3.3.5.3-1.

g. MNGP TS Table 3.3.5.1-1, Emergency Core Cooling System Instrumentation, does not include functions for manual initiation of Core Spray (CS) and Low Pressure Coolant Injection (LPCI). Since the design does not include this feature, proposed Table 3.3.5.3-1 does not include manual initiation functions for CS and LPCI. In addition, TS 3.3.5.3 does not include a surveillance requirement (SR) for a logic system functional test since the SR applies only to the manual initiation function. Therefore, as an alternative to NUREG-1433 SR 3.5.2.8, which demonstrates ECCS injection/spray actuation on a manual initiation signal, NSPM proposes TS 3.5.2, RPV Water Inventory Control, include a new SR (SR 3.5.2.7) to verify the required CS or LPCI subsystem can be manually operated through the manipulation of the subsystem components from the Main Control Room. The manual operation of the LPCI and Core Spray subsystems for the control of reactor cavity or RPV inventory are relatively simple evolutions and involve the manipulation of a small number of components. These subsystem alignments can be performed by licensed operators from the Main Control Room. This alternative is justified by the fact that a draining event is a slow evolution when compared to a design basis loss of coolant accident (LOCA), which is assumed to occur at full power, and thus there is adequate time to take manual actions (i.e., hours versus minutes). Adequate time to take action is assured since the proposed Technical Specification 3.5.2, Condition E, prohibits plant conditions that result in Drain Times that are less than one hour.

Therefore, there is sufficient time for the licensed operators to take manual action to stop an unanticipated draining event, and to manually start an ECCS injection/spray subsystem or the additional method of water injection.

Consequently, there is no need for manual initiation logic to actuate the required Draft

subsystem components. Manual operation of the required subsystem would be an equivalent alternative to system initiation via manual initiation logic.

h. The MNGP design does not provide the capability to perform channel checks for the following NUREG-1433 functions in proposed Table 3.3.5.3-1, "RPV Water Inventory Control Instrumentation": Function 1.c, "Reactor Steam Dome Pressure

- Low (Injection Permissive), Function 2.c, "Reactor Steam Dome Pressure -

Low (Injection Permissive)," and Function 2.d, "Low Pressure Coolant Injection Pump Discharge Flow - Low (Bypass)." The current TS do not include channel checks for these functions. Therefore, channel checks are not included for these functions.

i. MNGP TS 3.8.5, DC Sources - Shutdown, does not include NUREG-1433 Condition A, its associated Required Actions or COMPLETION TIMES. Nor does MNGP TS 3.8.5 contain NUREG-1433 Required Action B.1. Therefore, MNGP TS 3.8.5 Required Action A.1 corresponds with NUREG-1433 Required Action B.2.

The MNGP TS contain the following requirements that differ from the Standard Technical Specifications on which TSTF-542 was based, but are encompassed in the TSTF-542 justification:

j. MNGP TS Table 3.3.5.1, Functions 1.d and 2.d describe the Reactor Steam Dome Pressure Permissive-Low (Pump Permissive) functions for Core Spray and LPCI. These channels delay Core Spray and LPCI pump starts on Reactor Vessel Water Level - Low Low until reactor steam dome pressure is below the setpoint. This ensures that, prior to starting low pressure ECCS subsystem pumps, the reactor pressure has fallen to a value below these subsystems' maximum design pressure. This function is bypassed during manual operation; therefore, these Mode 4 and 5 functions and their corresponding surveillance requirements can be removed from the TS because the required ECCS subsystem is proposed to be started by manual operation.

k. MNGP TS Table 3.3.5.1, Functions 1.e and 2.e describe Reactor Steam Dome Pressure Permissive bypass time delays for the Core Spray and LPCI pumps.

The Bypass Timer channels allow the Core Spray and LPCI pumps to start on Reactor Vessel Water Level - Low Low after the bypass timer times out, even if the reactor steam dome pressure is above its permissive setpoint. This ensures that starting the pumps of the low pressure ECCS subsystems will occur on a Reactor Vessel Water Level - Low Low signal after an 18 minute time delay. This time delay is unnecessary for manual operation; therefore, these Mode 4 and 5 functions and their corresponding surveillance requirements can be removed from the TS because the required ECCS subsystem is proposed to be started by manual operation.

l. MNGP TS Table 3.3.5.1, Function 1.f, describes the Core Spray Pump Start -

Time Delay Relays for the Core Spray pumps. Along with the LPCI Pump Start -

Time Delay Relays (Function 2.f), the purpose of the time delay relays is to stagger the start of the CS and LPCI pumps that are in each of Divisions 1 and 2, Draft

thus limiting the starting transients on the 4.16 kV essential buses. This time delay is unnecessary for manual operation; therefore, these Mode 4 and 5 functions can be removed from the TS because the required ECCS subsystem is proposed to be started by manual operation.

m. MNGP TS lack a Control Room Air Inlet Radiation - High function (NUREG 1433 Table 3.3.7.1-1 Function 5). Instead, the equivalent function is performed by MNGP Table 3.3.7.1-1 Function 3, Reactor Building Ventilation Exhaust Radiation - High. Like the Control Room Air Inlet Radiation - High function, this function initiates the Control Room Emergency Filtration (CREF) System to isolate the control room envelope from untreated outside air. Therefore, the Reactor Building Ventilation Exhaust Radiation - High function is being revised accordingly.

n. In the MNGP TS, NUREG -1433 SR 3.5.2.2 and SR 3.5.2.3 are combined into a single SR 3.5.2.2 because the requirements for suppression pool water level and condensate storage tank levels are applicable to both CS and LPCI Systems, i.e.

both CS and LPCI Systems have the capability to draw a suction flow path from the CSTs and the Suppression Pool)..

o. TSTF-542 inadvertently omitted the corresponding TS Bases markup for the deletion of TS 3.3.6.1 Required Action I.2 regarding actions to isolate RHR shutdown cooling. MNGP TS Bases changes are made consistent with this TS change.

Draft

Draft