ML20063M131
| ML20063M131 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 09/03/1982 |
| From: | Tramm T COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 4938N, NUDOCS 8209100152 | |
| Download: ML20063M131 (2) | |
Text
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N C;mm:nw Elth Edison
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) one first N u_ronal_ Plaza. Chicago, IIljnois s
"7 Address Reply to Post Office Box 767
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,/ Chicago. Ilhnois 60690 September 3, 1982 Mr. Ha rold R. De n t o n, Direc to r Of fice of Nuclear Reactor Regulation U.S.
Nuclear Regulatory Commission Washington, DC 20555
Subject:
Byron Station Units 1 and 2 Braidwood Station Unit s 1 and 2 Containment Sump and Atmosphere Temperature Monitoring NRC Docket No s. 50-454, 50-455, 50-456, and 50-457
Dear Mr. Denton:
This is to provide information which will be added to the Byron /Braidwood FSAR regarding temperature monitoring o f the containment recirculation sump and atmosphere.
NRC review o f this information should close Confirmatory Issue 18 o f the Byron SER.
At tachment A to this letter contains our response to FSAR question 022.8.
It justifies the approach we have taken to monitoring the temperature o f the containment sump and atmosphere with regard to the Regulatory Position expressed in Revision 2 o f Regulatory Gu ide 1.9 7.
This information will be added to the FSAR at the earliest oppo rtunity.
Please address questions regarding this matter to this o f fi ce.
One signed original and fif teen copies o f this letter are provided for your review.
Ve ry truly yours,
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T Tramm Nuclea r Licensing Adminis trato r 1m Attachment A 8209100152 820903 PDR ADOCK 05000454 E
PDR 4Y36N
ATT ACHMENT A BYRO N /8R A IDWOO D CONTAINMENT SUMP AND A TMO SPHERE TEMPERATURE MONITORING Regulatory Position Fo r PWR 's Regula tory Gu ide 1.9 7, Rev.
2, identifies containment sump temperature and atmosphere temperature as important parameters for post-accident monitoring.
Both are categorized as Type D parameters in accordance with ANS-4.5 because they are parameters that provide information to indicate the operation o f individual safety systems and other systems important to safety.
Con tainmen t atmosphere temperature is to be measured in the range 400F to 400 F to indicate the accomplishment o f cooling.
Containment sump water temperature is to be measured in the range of 500F to 2500F, apparently to verify the adequate NPSH f or RHR and CS pumps during recirculation.
Design and qualification o f this instrumentation is to be Ca tegory 2 as defined in Reg. Guide 1.97.
Byron /Braidwood Al te rna tiv e The Byron design provides instrumentation adequate for operator monitoring of the containment cooling function.
Pa rar..e ter s mon i-tored include RCFC air inlet and outlet temperature (dewpoint and dry bulb), RCFC water inlet and outlet temperature, containment pressure, and containment spray flow.
This instrumentation is generally classified as Category 3 equipment per Regulatory Guide 1.97.
Temperature indication in other areas o f the containment atmosphere would not provide information useful to the operator in decisions regarding the operation of containment cooling equipment.
Containment sump water temperature indication, in conjunction with containment pressure indication, would only be useful to the operator to determine if adequate NPSH was available to the CS or RHR pumps when in the recirculation mode.
However, by design, cavitation of these pumps will not occur even if the water reaches containment saturation temperature.
The B/B design complies with NRC Reg. Guide 1.1 which states that " Emergency core cooling and containment heat removal systems should be designed so that adequate net positive suction head (NPSH) is provided to system pumps assuming maximum expected temperatures o f pumped fluids and no increase in containment pressure from tha t present prior to postulated loss o f coolant accidents."
Containment sump water temperature is therefore not a parameter required to indicate proper operation o f the CS or RHR systems when in the recirculation mode.
4938N