ML20076C993

From kanterella
Jump to navigation Jump to search
Forwards Extended Blowdown Test,Evaluation of Suppression Pool Temp Measurements, Providing Confirmation of Containment Adequacy Per NUREG-0808.Rept Fulfills SER Requirement for Actual Test Data
ML20076C993
Person / Time
Site: LaSalle  Constellation icon.png
Issue date: 08/16/1983
From: Schroeder C
COMMONWEALTH EDISON CO.
To: Harold Denton
Office of Nuclear Reactor Regulation
Shared Package
ML20076C995 List:
References
RTR-NUREG-0808, RTR-NUREG-808 7131N, NUDOCS 8308230245
Download: ML20076C993 (2)


Text

.

>* ' b * *

[]D Comm:nwealth Edison

, ) one First National Plaza. Chicago, Illinois 7 Address Reply to: Post Office Box 767

( -

(j Chicago, Illinois 60690 August 16, 1983 Mr. Harold R. Denton, Director Of fice of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

LaSalle County Station, Units 1 & 2 Thermal Adequacy of Suppression Pool (In-Plant SRV Test Results)

NRC Docket Nos. 50-373 and 50-374

Dear Mr. Denton:

Commonwealth Edison Company provided confirmation of the LaSalle containment adequacy per NUREG 0808 criteria via DAR Appendix I submittal on September 24, 1982. Subsequent to that report, in December 1982, an in-plant SRV discharge test was run to validate the thermal adequacy of the suppression pool. Among other objectives from that test was the verification of the suppression pool temperature monitoring system (SPTMS) to measu're and indicate the thermal response of the pool during and following SRV blowdown events. LaSalle SER 6.2 (NUREG 0519) requested that the bulk-to-local pool temperature differences be established by the LaSalle in-plant SRV test and that the maximum local pool temperature be verified, i

Prior suppression pool local and bulk temperature limits were based on NUREG-0487 analyses. A Tech Spec local temperature limit of j 2000 F was established from that basis. However, by resolution of NRC Task Action Plan 39, this limit was revised in NUREG-0783 to be dependent upon steam mass flux and the amount of subcooling of suppression pool water near the steam quench front. For LaSalle station this temperature

( bound ranges between 2000F and 216.50F for local temperatures based on NUREG-0783.

The actual suppression pool thermal response to SRV discha'ge r was measured as reported in the attached S&L report "LaSalle County 1 In-plant S/RV Test, Evaluation of Suppression Pool Temperature Measure-l ments". Results show the mean local-to-bulk pool temperature difference j

to be 8.10F (the 95/95 confidence level for non exceedance is 120F).

Test results also confirm that the SPTMS provides a conservative measure of bulk pool temperature. An evaluation of the LaSalle Technical Specifications relative to the currently imposed analytical pool limits was also made; the present specifications were found to have a 200F margin for suppression pool response to SRV blowdown.

8308230245 830816 ffC43 l PDR ADOCK 05000373 E PDR p

.- w . .

H. R. Denton August 16, 1983 This report fulfills the SER 6.2 requirement for actual test data on LaSalle suppression pool thermal response to SRV discharge phenomena.

To the best of my knowledge and belief the statements contained herein and in the Enclosure are true and correct. In some respects these statements are not based on my personal knowledge but upon information furnished by other Commonwealth Edison and contractor employees. Such information has been reviewed in accordance with Company practice and I believe it to be reliable.

Enclosed for you use please find one signed original and forty (40) copies of this report and the enclosure.

If there are any questions concerning this matter, please contact this office.

Very truly yours,

/

e C. . S hroeder Nucle r Licensin Administrator 1m e.

cc: NRC Resident Inspector - LSCS 4 Enclosure 7131N d

-r - - , , , - - , , , , - - , - . , . , ..,,-r- - , , - . , , - - - - , , - - - - - , - r-