Flex Refresher

Question 1

what is an ELAP?

Answer 1

Extended Loss of AC Power. expected to last longer than 4 hours.

Question 2

What is FLEX?

Answer 2

A diverse and flexible coping strategies following a beyond design basis event. Adds defense in depth.

Question 3

what is LUHS?

Answer 3

Loss of Ultimate Heat Sink.

Question 4

What is the Purpose of Flex?

Answer 4

Protect the fuel in the reactor.
Protect the fuel in the SFP.
Maintain Containment Function.

Question 5

What are the phases of Flex strategies, and what are the time lines?

Answer 5

First 6hrs. Phase 1. Initially cope using installed plant equipment.
From 6 to 24hrs. Phase 2 transition to on-site flex equipment.
After 24hrs. Phase 3 obtain additional off site capabilities.

Question 6

What is N and N+1 with regards to FLEX?

Answer 6

Sufficient equipment to address all functions on site plus one spare.

Question 7

Where is the flex equipment stored?

Answer 7

In protected area (Aux, Turbine, and fire pump house)

Dispersed on site (inside and behind the flex storage building and at the ISFIS pad.

Off site (national safer response center.

Question 8

what are the Flex Assumptions?

Answer 8

+ Its an beyond design basis that is caused by an external event, and effects all units.
+ Both units @ 100% power.
+ Both units reactor shut down successfully.
+ We are at Minimum staffing.
+ No other events are happing.
+ All people on site are available to support.
+ Spent fuel in dry cast is outside scope of FLEX.

Question 9

How do you enter the Flex guidelines?

Answer 9

From ECA0.0 or 4022-001-005 loss of offsite power with Reactor shutdown.

Question 10

How long should the station batteries last after a deep DC load shed?

Answer 10

12hrs

Question 11

What are the FLEX sources of Boric acid water?

Answer 11

BART, BAST, RWST.

Question 12

What are the FLEX sources of water for the SFP?

Answer 12

Fire Protection test header.

FLEX lift pump from the lake.