ML20138B059

Proposed Tech Spec 3.7.1.3,supplementing 850823 Request to Support Design Change Scheduled During Planned Outage in Oct 1985

ML20138B059
Person / Time
Site:	Grand Gulf
Issue date:	10/05/1985
From:	MISSISSIPPI POWER & LIGHT CO.
To:
Shared Package
ML20138B056	List: AECM-85-0326, Application for Amend to License NPF-29,supplementing 850823 Request.Amend Supports Design Change Scheduled During Planned Outage in Oct 1985 ML20138B059
References
TAC-59536, NUDOCS 8510150054
Download: ML20138B059 (3)

Text

. _ _ _ _ . _ _ _ ~ . _ _ . _ _. . ___ .

• < . l l

t 1.- NPE-85/14 and OLCR-NLS-85/04 (Supplemental Submittal) l

SUBJECT:

Technical Specification 3.7.1.3, page 3/4 7-4 '

!' DISCUSSION: Mississippi Power and Light-(MP&L) submitted proposed changes to the technical specifications and Facility Operating License NPF-29 in a letter from Mr. O. D. Kingsley, Jr. to Mr. Harold R.

p Denton, dated August 23, 1985. These proposed changes resulted i from a design change to increase the pumping capacity of Standby ,

j Service Water (SSW) loop B which is planned for implementation i during an outage scheduled to begin in October 1985. Recent

~ discussions with NRC staff concerning the changes submitted on August 23, 1985 have resulted in the technical specification

. clarification proposed in this submittal.

It is proposed to supplement the August 23, 1985 submittal by adding a "##" footnote to the required operational conditions i for the SSW basins in the subject technical specification to i read as follows:

l ## An OPERABLE basin shall have a 30 day supply of water i

either self contained or by means of an OPERABLE siphon.

! JUSTIFICATION: MP&L submitted Licensee Event Report 84-031-1 dated July 27, l 1984 (MP&L ~ correspondence number AECM-84/0376)' which describes problems associated with operation of the ultimate heat sink

(SSW). The minimum usable SSW basin water level was set at 107'0" from an original minimum level of 84'6" as a result of a deficiency involving inadequate SSW system flow through some -

l components. After the minimum basin level was changed it was f determined that for operation of Unit 1 alone, the combined capacity of the two SSW basins above elevation 107'0" is adequate to provide a 30 day inventory for post-LOCA operation. However, in the event of a LOCA coincident with a i loss of offsite power and a single active failure (loss of a division), the ability to transfer water to the operating basin

~ from the basin associated with the failed division is lost.

Thus, the 30 day basin water supply design requirement would not

! be met. A 3-inch siphon line was installed between SSW basins l'

A and B to transfer the necessary quantity of water needed for the 30 day post-LOCA operation.

l Larger SSW pumps are being installed in-the SSW basins in order to increase flow to SSW system loads at basin levels below 107'0" elevation. The August 23, 1985, submittal referenced above describes the proposed modification and implementation schedule for both basins.

+

l

&, h l _

J16ATTC85100'02 3 -11 1

- __ - . - . - . - _ - , _ , . - _ , - . ~ . . .. .. - _ , , . _ _ . . , , _ . . . . . . _ _ . - - . , . , . .. _ ,

a ,

This proposed change to the subject technical specification is provided to clarify SSW basin operability requirements to insure that the design requirement of a 30 day supply of water without makeup is provided in all required operational conditions.

This proposed change endorses the Grand Gulf interpretation of SSW basin operability requirements that has been in place since installation of the siphon between the SSW basins.

SIGNIFICANT HAZARDS CONSIDERATION:

The proposed change to the subject technical specification is provided for clarification of SSW operability requirements and endorses Grand Gulf interpretations of SSW basin operability.

The proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated because this change is provided only for clarification and does not change Grand Gulf interpretations of SSW basin operability requirements. The proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated because the clarification provided by this change will help ensure correct interpretations of SSW basin operability. The proposed changes do not involve a significant reduction in a margin of safety because the proposed change is only a clarification proposed to ensure consistent interpretations of SSW basin operability.

Therefore, the proposed change involves no significant hazards considerations.

l J16ATTC85100302 - 2

PLANT SYSTEMS ULTIMATE HEAT SINK LIMITING CONDITION FOR OPERATION 3.7.1.3 At least the following independent SSW cooling tower basins, each with:

a. A minimum basin water level at or above elevation 130'3" Mean Sea Level, USGS datum, equivalent to an indicated level of > 87".

b ~ Two OPERABLE cooling tower fans,#

shall be OPERABLE:

a. InOPERATIONALCondition1,2and3,twobasinsf

b. InOPERATIONALCondition4,5and*,thebasins#fssociatedwithsystems and components required OPERABLE by Specifications 3.7.1.1 and 3.7.1.2.

APPLICABILITY: OPERATIONAL CONDITIONS 1, 2, 3, 4, 5 and *.

ACTION:

a. In OPERATIONAL CONDITION 1, 2, 3, 4, 5 and

• with one SSW cooling tower basin inoperable, declare the associated SSW subsystem inoperable and, if applicable, declare the HPCS service water system inoperable, and take the ACTION required by Specifications 3.7.1.1 and 3.7.1.2, as applicable.

b. In OPERATIONAL CONDITION 1, 2, 3, 4 or 5 with both SSW cooling tower basins inoperable, declare the SSW system and the HPCS service water system inoperable and take the ACTION required by Specifications 3.7.1.1 and 3.7.1.2.

c. In Operational Condition

• with both SSW cooling tower basins inoperable, declare the SSW system inoperable and take the ACTION required by Specification 3.7.1.1. The crovisions of Specification 3.0.3 are not applicable.

SURVEILLANCE REQUIREMENTS 4.7.1.3 At least the above required SSW cooling tower basins shall be deter-mined OPERABLE at least once per:

a. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> by verifying basin water level to be greater than or equal to 87".

b. 31 days by starting from the control room each SSW cooling tower fan not already in operation and operating each fan for at least 15 minutes.

c. 18 months by verifying that each SSW cooling tower fan starts auto-matically when the associated SSW subsystem is started.

Whenhandlingirradiatedfuelintheprimaryorsecondarycontainment.

The basin cooling tower fans are not required to be OPERABLE for HPCS service water system OPERABILITY.

"An OPER A8LE ba. sin sho.ll ha.ve o. 30 d.o,.y supp1,3 of wa.ter either self-conta.ineal or by men.ns of an OPE 8ABLE siphon.

GRAND GULF-UNIT 1 3/4 7-4 Amend.me nt no.

._. . ~ - -