ML19254C994
| ML19254C994 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 09/11/1979 |
| From: | Reid R Office of Nuclear Reactor Regulation |
| To: | Groce R YANKEE ATOMIC ELECTRIC CO. |
| References | |
| NUDOCS 7910190260 | |
| Download: ML19254C994 (4) | |
Text
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UNITED STATES I-
! h y,( [,j NUCLEAR REGULATORY COMMISSION gg
,g WASHINGTON, D. C. 20555 e
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September 11, 1979 e
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Docket No. 50-309 Ii h
Mr. Robert H. Groce i
Licensing Engineer
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Yankee Atomic Electric Company
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20 Turnpike Road l
Westboro, Massachusetts 01581 I
Deer Mr. Gr' l
In response to our letter of September 2,1977 regarding steam generator water hamer you indicated that, based on your operating experience, modifications were not necessary to further reduce the probability or consequences of steam generator water hamer at your facility. Although your operating history does L
not show that such water hamer has occurred in your present piping arrangement, i
we require further assurance that steam generator water hamer will not occur in the future and that surveillance procedures would be adequate to detect water hamer or damage from water hamer if it were to occur.
Your response to the enclosed request for information, together with pre-viously supplied information, will provide a basis for a determination regarding
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the need for modifications to your feedwater system to prevent steam generator water hamer.
Your response is needed within 60 days so that we may maintain our schedule for evaluating the potential for water hamer at your facility.
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Sincerely,
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obert W. Reid, Chief i
Operating Reactors Branch #4 Division of Operating Reactors
Enclosure:
Request for Information Potential for Steam Generator Water Hammer cc w/ enclosure:
See next page 1i90 009 791010 0 L 6 o
Yankee Atomic Electric Company t
i cc:
E. W. Thurlow, President Mr. Robert R. Radcliffe flaine Yankee Atonic Power Company Office of Energy Resources l
9 Green Street 55 Capitol Street Augusta, flaine 04330 Augusta, Maine 04330 fir. Donald E. Vandenburgh Vice Pre! ' dent - Engineering
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Yankee A :nic Electric Ctmpany 20 Turnpike Road l
Westboro, flassachusetts 01581 C
John A. Ritsher, Esquire Ropes and Gray 225 Franklin Street i
Boston, Massachusetts 02110 f1r. John M. R. Paterson Assistant Attorney General State of Maine Augusta, Maine 04330 4
Mr. Nicholas Barth i
Executive Director l
Sheepscot Valley Conservation Association, Inc.
P. O. Box 125 l
Alna, Maine 04535 Wiscasset Public Library Association High Street Wiscasset, fiair.e 04578 Mrs. *.. Patricia Doyle, President SA:E POWER FOR MAINE Post Office Box 774 Canden,ftaine 04843
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s ENCLOSURE 1 I
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REQUEST FOR INFORMATION REGARDING THE POTENTIAL FOR STEAM GENERATOR WATER HAMMER AT P<ESSURIZED WATER REACTORS WITH FEEDRINGS THAT DISCHARGE FROM THE BOTTOM C
YlGUST 1979 1190 011 e
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1.
Provide infomation that demonstrates that the feedwater system and steam generator water level at your facility have been i
subjected to those transient conditions that are conducive i
to water hamer, i.e., the addition of cold feedwater or au..iliary feedwater to steam-filled feedwater piping and feedring.
See NUREG 0291 Page 4 that was.fomarded to you on September 2,1977.
l Include the following:
1.1 Describe the expected behavior of steam generator water level as a 1esult of reactor trip from power levels greater than 30% of full power.
Include actual plant measurements of steam generator level and other available related data such as fee %ater flew and auxiliary feedwater flow.
1.2 Provide the number and causes of loss of fecdwater events during the operational history of the planc.
You may refer to material submitted previously.
l 1.3 Provide the number and causes of loss of off-site power events during the operational history of the plant.
2.
If administrative controls have been adopted to limit the flow of auxiliary feedwater for the purpose of reducing the probability of water hamer, show when they were adopted and give the ansers to items 1.1,1.2 and 1.3 for before and after such controls were established.
3.
If administrative controls have been adepted to limit the flow of auxiliary feedwater for the purpose of reducing the probability of water hamer, show that an adequate water inventory and flow will be maintained to accomodate all postulated transient and accident conditions.
~4.
If auxiliary feedwater flow in your facility is not at present initiated automatically for normal and accident events, present your e' aluatinn of whether automating the actuation of auxiliary feedwater might increase the probability of inducing steam generator water hammer.
One of the signals that would automatically initiate the flow of auxiliary feedwater would be the steam generator low water level.
This set point should be above the top of the main feedwater sparger to reduce the probability of steam generator water hammer.
5.
Describe the means that will be used to menitor for the occurrence of steam generator water hammer and pessible damage frem such an event.
Include all instrumentation that will be employed.
Describe l
t..e inspections that will be perfomed and give the frequency of such inspections.
6.
Describe the reporting precedures that will be used to document and report water ha r er and damage to piping and piping support systems.
Such re:crts were recuested 'r cur letter : ycu dated Se;: ember 2, 1977.
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