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Draft Request for Addl Info Re Hydrological Considerations for CT Yankee Atomic Power Co,Haddam Neck Plant
	ML20039F838
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	12/30/1981
From:	Scherrer J; FRANKLIN INSTITUTE
To:	Fell R; NRC
Shared Package
ML20039F836	List: ML20039F835; ML20039F838;
References
	CON-NRC-03-79-118, CON-NRC-3-79-118, TASK-02-03.A, TASK-02-03.C, TASK-2-3.A, TASK-2-3.C, TASK-RR NUDOCS 8201130449
	Download: ML20039F838 (7)
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i REQUEST FOR ADDITIONAL INFORMATION i

r HYDROLOGICAL CONSIDERATION 5 CONNECTICUT YANKEE ATOMIC POWER COMPANY HADDAM NECK PLANT FRC PROJECT CS257 NRC DOCKET NO. 50-213 NRC TAC NO. 41362, 41351, 41340, 41329 FRC ASSIGNMENT 16 NRC CONTR ACT NO. NRC-03 79118 FRC TASK 425 Prepared by Franklin Research Center Author: J. Scherrer The Parkway at Twentieth Street Philadelphia, PA 19103 FRC Group Leader: J. Scherrer Prepared for Nuclear Regulatory Commission Washington, D.C. 20555 Lead NRC Engineer: R. Fell December 30, 1981 1

' 1 Franklin Research Center A Division of The Franklin Institute 8201130449 820111 DR ADOCK 05000213 p

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BACKGROUND is the result of an.

This Request for Additional Information (RFI) Licensee,. Connecticut Ya h

evaluation of the information submitted by t e attached bibliography h

Atomic Power Company (CYAP), and contained in t e tic Evaluation Program Further information is needed concerning Systemad II-3.C, " Safety-R

[1-S]. Topics II-3.A, " Hydrologic Description," anRC to resolve all outstanding (SEP)

Water Supply (Ultimate Heat Sink)," to enable F k Plant.

issues under these SEP topics for Haddam Nec Hydrologic Description Topic II-3.A l nt interfaces with the The purpose of this topic is to identify those p aor operating limitations i

hydrosphere that may require special plant des gnnts, and also to identify i

accommodate floods and water supply requ reme l nt operation.

Descriptions in and groundwater uses that may be affected by p acerns about the adequacy the Licensee's submittals raise certain con d of provisions for runoff to construction to sustain precipitation loading an prevent adverse flooding effects.

ITEM 1 CONCERN will caus? ponding on roofs Local probable maximum precipitation (PMP) Design ina tly not designed to shed the PMP.

large hydrostatic loads.

SEP Topic III-3.C, According to the Licensee's submittal [5] for" roof drains are not l

" Inservice Inspection of Water' Control Structures, Consequently, credit can i

ins'pected for clogging or debris accumulat on.f water discharge fro l

taken for roof drains as a means o that all roof drains are structures, and future evaluations will assume building roof' due to the clogged.

i In the worst case, the loading on the serv ceall drains to be clogged i

PMP would be approximately 42 psf, assum ngfor SEP Topic II-3.A,

" Hydrologic

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According to the Licensee's submittal [1load is 40 psf.

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Description," the plant roof design live A Dannen of The Fransan meeswee

fficient to permit a Information in the Licensee's submittals is not su Specifically, f structure.

determination of the structural adequacy of the rooides no engineering basis evaluation of the submitted information prov live load of 40 psf can safely i

conclusion that the roof with a design bas s load of 42 psf.

maintain its integrity under a precipitation tion of roofs of safety-It is the NRC staff's position that the construc of or store local i

related buildings should be adequate to safely d spose precipitation as severe as the PMP.

REQUEST i fall event known To aid evaluation, provide the frequency of the ra nprecipitation, i.e.,

to cause the most critical roof loading due toFor reference, give the local PM 1.

water ponded to the parapet tops.

values for the site.

i tion of the Provide sufficient information to enable a determ na lting from water adequacy of roof trusses to support the load re ii condition). If 2.

the Licensee's conclusion that roof design in the applied material or structural safety margins inherent limiting

~ structural design codes or standards, identify theFor these lim d discuss structural components.

extent to which allowable limits are exceeded an h

limits.

qualitatively the justification for exceeding t ese ITEM 2 CONCERN miles) can Fall of the PMP in a small geographic area (10 squareRegul potentially cause localized site flooding. infalls that cause ponding in the that the site be protected from intense ra ding that exceeds the capacity plant yard, specifically those which cause floo of the-yard drainage network.

i or' that all land area is graded to the r ver

-The Licensee has stated [1]

sive storm drainage discharge canal, thus precluding the need for an exte.1 i

has been However, the Licensee has not stated that the s tef or si system.

quantitatively evaluated for rainf all runof 2

i nklin Research Center ADhneson of N Frerdsninseue k

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Consideration must be_given to PMP runoff described in Regulatory Guide 1.59.

down the wooded slopes east of the plant with adverse antecedent moisture conditions and groundwater rising to plant grade.

REQUEST Provide a PMP runoff analysis conforming to the criteria in Regulatory U.S. Army Guide 1.59 for all local stream basins that surround the site.

Corps of Engineers Hydrologic Engineering Center models and Soil Conservation Service procedures are acceptable.

Safety-Related Water Su'pply (Ultimate Heat Sink)

Topic II-3.C The purpose of this topic is to determine the adequacy of onsite water sources with respect to providing safety-related water during emergency The location and inventory of shutdown and maintenance of safe shutdown.

safety-related water sources and the meteorologic conditions to be used in evaluating both temperature and inventory of the sources should be established.

In most cases, plants operating prior to 1973 will have to be reviewed to Prior to the establish the degree of conformance with current criteria.

issuance of Regulatory Guide 1.27 in 1973, the Standard Format and Content provided the only guidelines on ultimate heat sink (now Regulatory Guide 1.70)

Since compliance was not

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(UHS) requirements for prospective applicants.

required, and hydrologic and meteorologic criteria had not been established, More information is needed from the only minimal data were usually provided.

Licensee to resolve certain concerns.

ITEM 1 CONCERN According to the Licensee's submittal on this topic [4), the extreme low-water level of the Connecticut River was not available at the-t'im However, the Haddam Neck Facility Description and Safety their review.

(Docket No. 50-213) gives the minimum daily flow at the Analysis, Section 2.3, A branklin Research Center A Dms.on of The FranWm ineuwse

i lent to approxi-Thompsonville Station in 1949 and 1953 as 1,060 cfs, equ va mately 450,000 gpm.

lies require that Present NRC acceptance criteria for essential water supp lysis of low-flow determination for the primary water supply be b'as probable minimum flow.

Connecticut' River.

REQUEST f the Connecticut Provide an acceptable analysis of probable minimum flow o Show that the maximum water requirements for River at Haddam Neck Plant.

flow of the Connectic'ut normal operation are less than the probable minimum i

River.

ITDi 2 CONCERN Heat sink intakes should be located so that sediment cannot cau Although the Licensee's submittal for Inservice blockage of coolant water.

indicates that divers check for Inspection of Water Control Structures [5]

bmittal [4].

silt buildup three or fou' times a year, the, Ultimate Heat Sink suw does not clearly confirm that the The circulating and minimun flow will be directed to the intake structure. level of -2.0' ms1 service water system intakes were designed for a river ii m flow has (mean sea level), but the river water level at probable m n mu not been documented.

i 3 Also, the Licensee has used an excerpt from the Millstone Un t (PSAR), which shows a -2.6' msl mean low-Preliminary Safety Analysis Report ilability of the UES at water level of Iong Island So'und, to defend the ava for the The implication is that Long Island Sound is the UHS If this is the case, the Licensee must demonstrate that Haddam Neck.

Haddam Neck plant.

will always be the thalweg from Long Island Sound to the intake structure tdown of lower than -2.0' msl, sufficient to provide coolant water during a se River.

Long Island Sound and probable minimum flow of the Connecticut,

db FranklinResearchCenter A Dwwon of The FransenInseuse

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REQUEST Show that the water level at the* intake structure under conditions of probable minimum flow of the Connecticut River will always be sufficient. to provide cooling water for safe shutdown and cooldown in the short term (30 days) and to maintain a safe shutdown condition for the long term.

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A DMoos of The Freewan insmause

o BIBLIOGRAPHY 1.

W. G. Counsil (CYAP)