ML021360432

Technical Specification Pages for Amendment 205 Surveillance Requirements Associated with the Containment Airlock

ML021360432
Person / Time
Site:	Millstone
Issue date:	05/15/2002
From:	NRC/NRR/DLPM
To:
References
TAC MB2930
Download: ML021360432 (4)

Text

CONTAINMENT SYSTEMS CONTAINMENT AIR LOCKS LIMITING CONDITION FOR OPERATION 3.6.1.3 The containment air lock shall be OPERABLE wiith:

a.

Both doors closed except when the air lock is being used for normal transit entry and exit through the containment, then at least one air lock door shall be closed, and

b.

An overall air lock leakage rate in accordance with the Containment Leakage Rate Testing Program.

APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTION:

NOTE Entry and exit through the containment air lock doors is permitted to perform repairs on the affected air lock components.

a.

With only one containment air lock door inoperable:

1.

Verify the OPERABLE air lock door is closed within I hour and either restore the inoperable air lock door to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or lock the OPERABLE air lock door closed.

2.

Operation may then continue provided that the OPERABLE air lock door is verified to be locked closed at least once per 31 days.

3.

Otherwise, be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />, and.

4.

Entry into an OPERATIONAL MODE is permitted while subject to these ACTION requirements.

b.

With only the containment air lock interlock mechanism inoperable, verify an OPERABLE air lock door is closed within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and lock an OPERABLE air lock door closed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Verify an OPERABLE air lock door is locked closed at least once per 31 days thereafter.

Otherwise, be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

(Entry into and exit from containment is permissible under the control of a

dedicated individual).

MILLSTONE - UNIT 3 3/4 6-5 Amendment No. F7, *,

0801

, 205

CONTAINMENT SYSTEMS CONTAINMENT AIR LOCKS LIMITING CONDITION FOR OPERATION Continued

c.

With the containment air lock inoperable, except as specified in ACTION

a. or ACTION b. above, immediately initiate action to evaluate overall containment leakage rate per Specification 3.6.1.2 and verify an air lock door is closed within I hour.

Restore the air lock to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Otherwise, be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

SURVEILLANCE REQUIREMENTS Each containment air lock shall be demonstrated OPERABLE:

a.

By verifying leakage results in accordance with the Containment Leakage Rate Testing Program.

Containment air lock leakage test results shall he evaluated against the leakage limits of Technical Specificaticn 3.6.1.2.

(An inoperable air lock door does not invalidate the previeus successful performance of the overall air lock leakage test).

b.

Deleted

c.

At least once per 24 months by lock can be opened at a time.

MILLSTONE

- UNIT 3 3/4 0801 verifying that only one door in each air 6-6 Amendment No.

ýý, 79, ;90,2Q5 i

I

BASES 3/4.6.1.2 CONTAINMENT LEAKAGE (continued) are representative of those which would occur at accident pressure while meeting the intent of the LCO.

This test methodology is in accordance with the Containment Leakage Rate Testing Program.

The surveillance testing for measuring leakage rates are in accordance with the Containment Leakage Rate Testing Program.

The enclosure building bypass leakage paths are listed in the "Technical Requirements Manual." The addition or deletion of the enclosure building bypass leakage paths shall be made in accordance with Section 50.59 of IOCFR50 and approved by the Plant Operations Review Committee.

3/4.6.1.3 CONTAINMENT AIR LOCKS The ACTION requirements are modified by a Note that allows entry and exit to perform repairs on the affected air lock components.

This means there may be a short time during which the containment boundary is not intact (e.g., during access through the OPERABLE door).

The ability to open the OPERABLE door, even if it means the containment boundary is temporarily not intact, is acceptable due to the low probability of an event that could pressurize the containment during the short time in which the OPERABLE door is expected to be open.

After each entry and exit. the OPERABLE door must be immediately closed.

ACTION a. is only applicable when one air lock door is inoperable.

With only one air lock door inoperable, the remaining OPERABLE air lock door must be verified closed within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

This ensures a leak tight containment barrier is maintained by use of the remaining OPERABLE air lock door.

The 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> requirement is consistent with the requirements of Technical Specification 3.6.1.1 to restore CONTAINMENT INTEGRITY.

In addition, the remaining OPERABLE air lock door must be locked closed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and then verified periodically to ensure an acceptable containment leakage boundary is maintained.

Otherwise, a plant shutdown is required.

ACTION b. is only applicable when the air lock door interlock mechanism is inoperable.

With only the air lock interlock mechanism inoperable, an OPERABLE air lock door must be verified closed within I hour.

This ensures a leak tight containment barrier is maintained by use of an OPERABLE air lock door.

The I hour requirement is consistent with the requirements of Technical Specification 3.6.1.1 to restore CONTAINMENT INTEGRITY.

In addition, an OPERABLE air lock door must be locked closed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and then verified periodically to ensure an acceptable containment leakage boundary is maintained.

Otherwise, a plant shutdown is required.

In addition, entry into and exit from containment under the control of a dedicated individual stationed at the air lock to ensure that only one door is opened at a time (i.e., the individual performs the function of the interlock) is permitted.

ACTION c. is applicable when both air lock doors are inoperable, or the air lock is inoperable for any other reason excluding the door interlock mechanism.

With both air lock doors inoperable or the air lock otherwise inoperable, an evaluation of the overall containment leakage rate per Specification 3.6.1.2 MILLSTONE - UNIT 3 B 3/4 6-1a Amendment No.

g, g, Xg, 0802

X77, I9, 205

BASES 3/4.6.1.3 CONTAINMENT AIR LOCKS (continued) shall be initiated immediately, and an air lock door must be verified closed within I hour.

An evaluation is acceptable since it is overly conservative to immediately declare the containment inoperable if both doors in the air lock have failed a seal test or if overall air lock leakage is not within limits.

In many instances (e.g..

only one seal per door has failed),

containment remains

OPERABLE, yet only I hour (per Specification 3.6.1.1) would be provided to restore the air lock to OPERABLE status prior to requiring a plant shutdown.

In addition, even with both doors failing the seal test, the overall containment leakage rate can still be within limits.

The I hour requirement is consistent with the requirements of Technical Specification 3.6.1.1 to restore CONTAINMENT INTEGRITY.

In addition, the air lock and/or at least one air lock door must be restored to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or a plant shutdown is required.

Surveillance Requirement 4.6.1.3.a verifies leakage through the containment air lock is within the requirements specified in the Containment Leakage Rate Testing Program.

The containment air lock leakage results are accounted for in the combined Type B and C containment leakage rate.

Failure of an air lock door does not invalidate the previous satisfactory overall air lock leakage test because either air lock door is capable of providing a fission product barrier in the event of a design basis accident.

The limitations on closure and leak rate for the ccntainment air locks are required to meet the restrictions on CONTAINMENT INTEGRITY and containment leak rate.

Surveillance testing of the air lock seals is performed in accordance with the Containment Leakage Rate Testing Program, which ens,,res that the overall air lock leakage will not become excessive due to seal damage during the intervals between air lock leakage tests.

While the leakage rate limitation is specified at accident pressure, P,. the actual surveillance testing is performed by applying a pressure greater than or equal to Pa.

This higher pressure accounts for test instrument uncertainties and test volume stabilization changes which occurs under actual test conditions.

3/4.6.1.4 and 3/4.6.1.5 AIR PRESSURE and AIR TEMPERATURE The limitations on containment pressure and average air temperature ensure that:

(1) the

..-,tainment structure is prevented from exceeding its design negative pressure of 8 psia, and (2) the containment peak pressure does not exceed the design pressure of 60 psia during LOCA conditions.

Measure ments shall be made at all listed locations, whether by fixed or portable instruments, prior to determining the average air temperature.

The limits on the pressure and average air temperature are consistent with the assumptions of the safety analysis.

The minimum total containment pressure of 10.6 psia is determined by summing the minimum permissible air partial pressure of 8.9 psia and the maximum expected vapor pressure of 1.7 psia (occurring at the maximum permissible containment initial temperature of 120°F).

MILLSTONE - UNIT 3 B 3/4 6-1b Amendment No.

F, 7F, 0802

X77, 199,205