ML20116J709

Corrected Proposed TS 3.2/4.2-8 Re Administrative Changes

ML20116J709
Person / Time
Site:	Quad Cities
Issue date:	11/06/1992
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML20116J698	List: ML20116J695 ML20116J709
References
NUDOCS 9211160316
Download: ML20116J709 (1)

Text

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r I* QUAD CITIES DPR-30 of the tripping contar:s is such as to provide this function when necessary and minimize spurious operation. The trip settings given in the specification are adequate to assure the above criteria are met (reference UFSAR Section 7.3.1.4). '

T;.a specification preserves the effectiveness of the system during perleds of maintenance, testing or calibration and also minimizes the risk of inadvertent operation, i.e., only one instrument channel out of service.

Two radiation monitors are provided on the refueling floor which initiate isolat!on of

' the logicreactor building is one out of two.andTripoperation settings ofofs the 100standby mR /hr for the monitors on thegas treatmen refueling floor are based upon initiating normal ventilation isolat!on and standby gas treatment system operation so that none of the activity released during the refueling accident leaves the reactor building via the normal ventilation stack but that all the activity is processed by the standby gas treatment system.

The instrumentation which is provided to monitor the postaccident condition is listed in Table 3.2-4. The instrumentation listed and the limiting conditions for operation on these systems ensure adequate monitoring of the containment following a lossof coolant accident. Information from this instrumentation will provide the operator with a detailed knowledge of the conditions resulting from the accident; based on this information he can make logical decisions regarding postaccident recovery.

The specifications allow for postaccident instrumentation to be out of service for a pedod of 7 days. This period is based on the fact that several diverse instruments are available for guiding the operator should an accident occur, on the low probability of an instrument being out of service and an accident occurring in the 7-day period, and on engineering judgment.

The normal supply of air for the control room ventilation system Trains "A" and "B" is outside the service building. In the event of an accident, this source of air may be required to be shut down to prevent high doses of radiation in the control room.

Rather than provide this isolation function on a radiation monitor installed in the intake air duct, signals which indicate an accident, i.e., high drywell pressure, low water level, main steamline high flow, or high radiation in the reactor building ventilation duct, w!!i muse isolation of the intake air to the control room. The above trip signals result in inimediate isolation of the control room ventilation system and thus minimize any radiation dose. Manualisolation capability is also provided.

Isolation from high toxic chemical concentration has been added as a result of the

" Control Room Habitability Study" submitted to the NRC in December 1981 in response to NUREG-0737 Item lli D.3.4. Ammonia, chlorine and sulphur dioxide -

detection capability was added to the plant in response to the referenced study, in a report generated by Sargent and Lundy in April 1991, justification was provided to delete the chlorine and sulphur dioxide detectors from the plant. The setpoints chosen for the control room ventilation isolation are based on early detection in the outside air supply at the odor threshold, so that the toxic chemical will not achieve-texicity limit concentrations in the Control Room.

The radioactive liquid and gaseous eff!uent instrumentation is providad to monitor  !

the release of radioactivo materials in liquid and gaseous effluents during releases. l The alarm setpoints for the instruments are provided to ensure that the alarms will occur prior to exceeding the limits of 10 CFR 20.

9211160316 921106 DR ADOCK 0500 4 Amendment No, -

0560J p .2/4.2-8 ZNLD/2267/1