ML19105A215

From kanterella
Jump to navigation Jump to search
Notifying Incident During Thermal Limitations on Condenser Cooling Water Discharge Were Exceeded
ML19105A215
Person / Time
Site: Surry  Dominion icon.png
Issue date: 07/23/1975
From: Stallings C
Virginia Electric & Power Co (VEPCO)
To: Goller K
Office of Nuclear Reactor Regulation
References
Serial No. 609
Download: ML19105A215 (1)


Text

~-, -*--';:;._,~_.,<,.,.~.-:...~,--tJ....,.,.c.'....,*~~'-.--.-.....:z,, *-*~.,: *i.:',.. ~vt# *.....,.~ *.** *.**_a;_;:,,~*.*** *.i....:...;';%' *'~,,*

-,*:,~~~**~* *****~*,... **-.....:.....<,"c:'~ *,-.*-a*,-,------*---. **.:...c..:.&.:i........~*..=;. -

- ::.:.ii>>::.-:,~~1,--,

i Mr. K. R. Goller, Assistant Director for Operating Reactors Division of Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D. C.

20555

Dear Mr. Goller:

Serial No. 609 PO&M/JTB:clw Docket Nos. 50-280 50-281 License Nos. DPR-32 DPR-37 In accordance with the Surry Power Station, Unit Nos. 1 and 2, Technical Specifications, this is. to notify you of an incident during which the thennal limitations on the condenser cooling water discharge were exceeded.

The incident occurred on July 11, *1975 while escalating power on Unit No.

2*following a unit start-up.

The unit was at approximately 48 per cent of rated thermal power and 340 MWe.

At this time during the power escalation, two circulating water pumps were started and the condenser outlet valves positioned to maintain intake canal level.

Subsequent monitoring of the cir-culating water temperatures revealed that the increase in flow thro_ugh the condenser caused the temperature at the discharge control structure to decrease 3.5 degrees Fin approximately fifteen (15) minutes.

There was no further de-crease in the discharge temperature during the hour.

Technical Specification 4.14.A.3 requires that the cooling water temperature at the discharge control structure not exceed an average rate of change of 3 d.egrees F per hour.

There was no evidence of any adverse environmental impact caused by the incident.

Analysis of the occurrence indicates that the rate of circulating water flow through the condenser was increased too rapidly.

In order to prevent recurrence, operating personnel have been instructed to exercise more caution when operating the condenser water boxes and to monito.r the circulating water temperatures closely during the operation.

The operating procedures for the circulating water system are being revised to reflect these precautions and to limit starting of the circulating water pumps to.one at a time at sufficient intervals to avoid~ceeding the maximum rate of change of temperature at the discharge c0~~lft

~ture.

{~'>'Y

, -~:\\*-,*~.,

Q"

,,/

c1(r.i1:.D*

'<.," ~~

_.,dV~e:er 7

y~t-,r~uz...1"'1'.y yours,,i **.---**, ~

'::j o~~ti~Q

~\\

E:_/

.. ~')*"'\\970/" ~~

~

~

j\\l\\._.. *.,~

9 J

1..r,.10?.:,\\

  • i r,ct>-R Rea~

._, 4*

C.

ings

\\':'.,.,....

\\).s. ';-\\io:'"'1S'\\:~n

'-. /

President-Power Supply

\\ ~

J,t,.o'il Sec 0.. /,

Production Operations

~-lS;,_3'/~

I I

/.