ML20070S085

Provides Update on Actions Pertaining to NRC GL 89-13 W/ Regard to RHR HX Testing

ML20070S085
Person / Time
Site:	LaSalle
Issue date:	05/18/1994
From:	Lockwood J COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-89-13, NUDOCS 9405230208
Download: ML20070S085 (2)

Text

4 a'

C:mmonw;2lth Edison j

LaSalle County Nuclear Station 2601 N. 21st. Rd.

I Marseilles, Illinois 61341 Telephone 815/357-6761 i

May 18, 1994 U.S. Nuclear Regulatory Commission Washington, D.C.

20555 j

Attention:

Document Control Desk l

Subject:

LaSalle County Station Units 1 and 2 Service Water System Problems Affecting Safety-Related Equipment.

(Supplemental Response to NRC Generic Letter 89-13)

NRC Docket Numbers 50-373 and 50-374

References:

1)

M.H. Richter letter to NRC dated January 29, 1990; Generic Letter 89-13 Responses.

The purpose of this letter is to provide an update on LaSalle County Station's (LSCS) actions pertaining to NRC Generic Letter 89-13 with regard to Residual Heat Removal (RHR) heat exchanger testing.

In the original response to the NRC (Reference 1) it was stated (page D-5) that the Core Standby Cooling System (CSCS)

Heat Exchanger Testing Program would be revised with new testing / maintenance requirements which would require monitoring and trending of the heat transfer performance, or monitoring flowrates and differential pressures, along with inspection and maintenance.

Following the initial three tests and/or inspections, a final frequency for testing and/or inspections will be chosen for an ongoing monitoring program.

LaSalle County Station now intends to continue to perform the service water flowrate/dP testing at least every 18 months for each RHR heat exchanger, and perform a visual inspection (along with cleaning and maintenance as needed) of the service water l

side (tube side) of each of the RHR heat exchangers at least every 5 years.

The heat transfer testing will no longer be i

performed on a regular basis for the following reasons:

A.

For Unit 1, the "1A" RHR heat exchanger has had 3 heat transfer tests without any cleaning between tests and all have passed. For Unit 2, the "2L'" RHR heat i

exchanger has had 3 heat transfer teats without l

cleaning and all have passed.

The "2B" and the "2A" l

RHR heat exchangers have each had 2 helt transfer tests without cleaning between them and have passed.

/

9405230208 940519 q{kM T

PDR ADOCK 05000373

/

l P

PDR i

0

9 B.

Periodic visual inspections of "As-found" conditions of the service water side of each RHR heat exchanger during the previous 2 refuel outages for Unit 2 and the previous refuel outage for Unit 1 have shown no significant fouling of the heat exchangers.

C.

The Service Water Chemical Feed system has been seen to reduce fouling system-wide.

D.

It is often difficult to obtain the temperature differences required in order to perform the heat transfer testing.

The suppression pool has a maximum temperature limit, while the cooling lake has a limited temperature range.

This restricts the available differential temperatures to get good data.

If there are any questions or comments regarding this supplemental response to Generic' Letter 89-13, please contact me at (815) 357-6761, extension 2246.

The LaSalle Site Vice President has reviewed and concurred with this updated response.

Sincerely,

}

l

-Johnny Lockwood Regulatory Assurance' Supervisor LaSalle County Station I

l cc:

J.B. Martin, Regional Administrator-RIII Senior Resident Inspector-LSCS A.T. Gody, Jr.,

Project Manager, NRR Office of Nuclear Facility Safety-IDNS D.L.

Farrar, Nuclear Regulatory Services Manager,-NORS Station File i

_