Entry Conditions:

Any indication of 1 or more rods not responding to demand

Console or P-250 IRPI indicate misalignment from GDC within 1 hour of rod motion

±18 steps when ≤85% power

±12 steps when >85% power

Entry directed by OHA ‘E’ alarm response

Continuous Action Summary: None

Paths:

Place rod bank selector in manual.

Misaligned Rod

Adjust power with boration and turbine or steam dumps to ±1.5°F only if required . Only maintain temperature with the Turbine or Dumps -- Boron is only used if a significant power reduction is necessary.

Bad IRPI – AB.Rod-0004

More than one rod – Hot Standby w/in 6 hours by Borating

AB.Load-0001 to <75%

Re-align rod to bank. If immovable – perform Shutdown Margin surveillance w/in 1 hour and Hot Standby w/in 6 hours.

Immovable Rod

Perform Shutdown Margin surveillance w/in 1 hour and Hot Standby w/in 6 hours.

Bases:

Maintain acceptable power distribution limits, maintain minimum SDM requirements.

Limit the potential affects of rod misalignment on the associated accident analysis
RCCA Misalignment Analysis from FSAR Condition II Events: The most severe misalignment situations with respect to DNBR at significant power levels occur when one RCCA is fully inserted with either all rods out, or bank D in at its insertion limit, or when bank D is inserted to its insertion limit with one RCCA fully withdrawn.The bank can be inserted to its insertion limit with any one assembly fully withdrawn or inserted without DNBR falling below the limit value.

Notes

Notes

T_avg ±1.0°F before moving Rod Bank Selector thru auto.

If a Rod Bank Urgent Failure Alarm exists, it must be corrected before any attempts to move rods.

A dropped rod is also a misaligned rod.

Recovery

Record the # steps out of alignment, GP steps, and if it is a GP I rod in a control bank, the P/A Converter reading

Rod higher than bank à ADD # of re-align steps         Rod lower than bank à SUBTRACT # of re-align steps

While re-aligning rod, can use ANY method to maintain T_AVE

Rod higher than bank and GP II à insert and withdraw extra step to make sure rod will now sequence correctly

Rod lower than bank and GP I à withdraw then insert extra step

If it is a GP I rod in a control bank, reset the P/A Converter (to the original number)

Entire bank à test inward motion first 'cuz no interlocks

AB-ROD-0002                   Dropped Rod(s)

Entry Conditions:

Indication that one control rod has partially or fully dropped without a reactor trip

Indication that more than one rod has partially or fully dropped without a reactor trip

Paths:

Place rod bank selector in manual (prevents outward rod motion due to T_AVG error)

Stabilize the plant by stopping turbine load changes and boron concentration changes

Adjust TAVG to ±1.5°F of program using steam demand same as AB.ROD-0001

If Reactor is subcritical as a result of the dropped rod game over, insert coins

Insert all shutdown and control rods

Refer to TS and exit procedure (control rod recovery would constitute an approach to criticality)

If the reactor remains critical following the dropped rod

If a power reduction becomes necessary, borate and adjust turbine load or steam dump demand (avoids further rod motion and the possibility of additional dropped rods)

If power is >50%, monitor QPTR, AFD, rod bottom light, rod bottom alarm, & T_AVG - T_REF Dev.

If an IRPI malfunction has occurred go to AB-ROD-0004(addresses initiating conditions at low power levels)

INITIATE a power reduction to <75% Rated Thermal Power IAWAB.LOAD. (Initiates a power reduction to <75% power to ensure that the 1 hour requirement of Technical Specifications is complied with.)

Request reactor engineering assistance to determine if the rod is to be recovered

Refer to TS 3.1.3.1 & 3.1.3.4

If the rod is not fully inserted, go to AB-ROD-0001(steps are different for a  misaligned rod, specifically the P/A converter and GDC settings)

Obtain reactor engineering approval to realign the rod including the number of steps, power level, and duration of time to realign

Realign the rod as follows:

Record the GDC reading associated with affected rod

Record the P/A converter reading for the affected bank, then zero the affected bank (this will actuate the RIL LO & LO LO alarms –only required for a group 1 rod since group 1 data logging card provides P/A input)

Set the applicable group step counter to zero.

Place the group lift coil disconnects for unaffected rods off (a rod bank urgent failure due to a regulation failure will occur for all banks except SC & SD and a RIL low low may actuate when a group 1 rod is stepped in due to P/A converter input into the RIL computer)

Realign the rod within the time specified while maintaining TAVG ±1.5°F of program (ensure TAVG is ±1°F before operating the rod bank selector through auto to prevent rod motion and misalignment of the bank overlap unit)

Following alignment, insert the misaligned rod one step and then withdrawal one step if the affected rod was a group 1 rod (except SC & SD) (ensures proper group sequencing logic)

Place all lift coil disconnects on

If a power range rate trip has occurred on any channel reset the trip bistable (Note that this step is bypassed if rod motion did not occur.  The reason for this is that if another rod were to drop and cause a second NI channel to trip, a Reactor trip would not be prevented.)

Depress the ‘alarm reset’ bezel to clear the ROD BANK URGENT FAIL alarm (resets urgent failure, memory buffer, & slave cycler)

Perform ST.RCS-0001 for the affected bank and exit this procedure

If the rod is immovable place the unit in Mode 3 IAW applicable IOPs (TS 3.1.3.1.a)

AB-ROD-0003                             Continuous Rod Motion

Entry Conditions:

Any unwarranted continuous rod motion

3 or more concurrent steps at steady state conditions (rod stopping due to noise is expected to be ~2 steps)

Immediate Actions: nope, not for this one

Continuous Actions: None

Paths:

Place rod bank selector in manual.  If rod motion does not stop, Trip | Confirm | EOP-TRIP-1