ML20082L284

Proposed Tech Specs,Allowing Removal of H Ingniters in Incore Instrument Tunnel for Each Train of H Mitigation Sys

ML20082L284
Person / Time
Site:	Catawba
Issue date:	04/10/1995
From:	DUKE POWER CO.
To:
Shared Package
ML20082L282	List: ML20082L278 ML20082L284
References
NUDOCS 9504210087
Download: ML20082L284 (3)

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ATTACIIMENT 4 PROPOSED TECIINICAL SPECIFICATION AMENDMENTS FOR CATAWBA 9504210087 95041o PDR P

ADOCK 05000413 PDR

C0 TAINMENT SYSTEMS HYOR0 GEN MITIGATION SYSTEM LIMITING CONDITION FOR OPERATION 3.6.4.3 Both trains of the Hydrogen Mitigation System shall be OPERABLE.

APPLICABILITY: MODES 1 and 2.

ACTION:

With one train of the Hydrogen Mitigation System inoperable, restore the inoperable train to OPERABLE status within 7 days or increase the surveillance interval of Specification 4.6.4.3a. from 92 days to 7 days on the OPERABLE train until the inoperabia train is returned to OPERABLE status.

SURVEILLANCE REOUIREMENTS 4.6.4.3 Each train of the Hydrogen Mitigation System shall be demonstrated OPERABLE:

a. At least once per 92 days yb energizing the supply breakers and verifying that at least ,P5 of,3r igniters are energi:ed," and l b.

3+ 35 At least once per 18 months by verifying the temperature of each igniter is a minimum of 1700*F.

" Inoperable igniters must not be on corresponding redundant circuits which provide coverage for the same region.

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l CATAWBA - UNITS 1 & 2 3/4 6-40 A

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4 l CONTAINMENT SYSTEMS i

BASES i 3/4.6.2 OEPRESSURIZATION AND COOLING SYSTEMS-

! The OPERABILITY of the Containment Spray System ensures that containment ,

l depressurization and cooling capability will be available in the event of a l

LOCA. The pressure reduction and resultant lower containment leakage rate are l consistent with the assumptions used in the safety analyses. However, the

Containment Spray System also provides a mechanism for removing iodine from the containment atmosphere, and therefore the time requirements for restoring an inoperable Spray System to OPERABLE status have been maintained consistent 4

with those assigned other inoperable ESF equipment. t

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3/4.6.3 CONTAINMENT ISOLATION VALVES -

The OPERABILITY of the containment isolation valves ensures that the i containment atmosphere will be isolated from the outside environment in the i event of a release of radioactive material to the containment atmosuhere or q pressurization of the containment and is consistent with the req:;iraments of j GDC 54 through 57 of Appendix A to 10 CFR Part 50. Containmer,i. isolation within the time limits specified for those isolation valves designed to close auto- ,

matically ensures that the release of radioactive material to the environ-ment will be consistent with the assumptions used in the analyses for a LOCA.

T 3/4.6.4 COMBUSTIBLE GAS CONTROL  !

The OPERABILITY.of the equipment and systems required for the detection and control of hydrogen gas ensures that this equipment will be available to maintain the hydrogen concentration within containment. below its flammat i .

limit during post-LOCA conditions. Either recombjner unit is capable of I controlling the expected hydrogen generation associated with: (1) zirconium-water reactions, (2) radiolytic decomposition of water, and (3) corrosion of metals within containment. These Hydrogen Control Systems are consistent with the recommendations of Regulatory Guide 1.7, " Control of Combustible Gas Concentrations Following a LOCA," March 1971.

7+.ef 7J~ - f,F 70 The OPERABILITY of at least)'f)6)Hf igniters per train (70'of M for both l trains) ensures that the Distributed Ignition System will maintain an effective coverage throughout the containment provided the two inoperable ignitors are' not on corresponding redundant circuits which provide coverage for the same region.

This system of igniters will initiate combustion of any significant amount of I hydrogen released after a degraded core accident. This system is to ensure l burning in a controlled manner as the hydrogen is released instead of allowing it to be ignited at high concentrations by a random ignition source.

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