Section 2.0 Safety Limits

Question 1

• LCO 2.1.2 RCS Pressure*
• • *

When is LCO 2.1.2 RCS Pressure Applicable?

Answer 1

MODES 1 - 5

Question 2

• LCO 2.2.1 RTS Instrumentation*
• • *

What Rx trips provide DNB protection?

Answer 2

OT∆T

PZR Pressure - Low

Rx Coolant Flow - Low

RCP Undervoltage

RCP Underfrequency

Question 3

• LCO 2.1.1 Reactor Core Safety Limits*
• • *

What is the DNBR Limit and the Peak Centerline Temperature Limit?

Answer 3

DNBR Limit

≥ 1.17

Peak Centerline Temperature

< 5080 ˚F

Lowers 58 ˚F / 10,000 MWD/MTU Burnup

Question 4

• LCO 2.2.1 RTS Instrumentation*
• • *

What is the bases for the OP∆T Rx Trip?

Answer 4

Protects the fuel

Provides protection for SLBs

Note:
OT∆T is for DNB protection

Question 5

• LOT 110.02 Safety Limits*
• • *

What are the bases for the different regions of the Reactor Core Safety Limits - 4 Loops in Operation COLR graph (T_avg vs RTP)?

Answer 5

Flat Region (Green)

Ensures that no bulk boiling will occur at the core exit so that the OPΔT and OTΔT trips remain functional

Steep Region (Pink)

Assures that DNB does not occur (DNBR is maintained >1.52)

Question 6

• LCO 2.1.2 RCS Pressure*
• • *

What is the RCS pressure limit per Tech Specs?

Answer 6

2735 psig

2485 psig x 110%

Question 7

• LCO 2.1.1 Reactor Core Safety Limits*
• • *

What are the requirements of 10CFR50.36(c)(1)?

Answer 7

Shutdown the reactor

4 hour notification to NRC

Submit an LER w/in 60 days

Operation SHALL NOT resume until authorized by the NRC.

Question 8

• LCO 2.1.1 Reactor Core Safety Limits*
• • *

When is LCO 2.1.1 Reactor Core Safety Limits Applicable?

Answer 8

MODES 1 - 2

Question 9

• LCO 2.1.1 Reactor Core Safety Limits*
• • *

What are your ≤ 1 hour action(s) if the combination of RTP, P_PZR, and highest operating loop T_avg exceed their limits?

Answer 9

• LCO 2.1.1 Reactor Core Safety Limits*
• Action A*
• • *

Be in MODE 3 [1 hr]

Question 10

• LCO 2.1.2 RCS Pressure*
• • *

What are your ≤ 1 hour action(s) if the RCS Pressure Limit is exceeded?

Answer 10

MODES 1-2

Be in MODE 3 [1 hr]

Lower RCS pressure < Limit [1 hr]

MODES 3-5

Lower RCS pressure < Limit [5 mins]

Question 11

• LCO 2.2.1 RTS Instrumentation*
• • *

What is the bases for the PR Flux Rate - High Rx Trip?

Answer 11

Protects against:
Uncontrolled RCCA withdrawal at power
Rupture of CRDM