ML17309A122
| ML17309A122 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 01/28/1981 |
| From: | Maier J ROCHESTER GAS & ELECTRIC CORP. |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| TASK-02-03.A, TASK-02-03.B, TASK-02-03.C, TASK-2-3.A, TASK-2-3.B, TASK-2-3.C, TASK-RR NUDOCS 8102040327 | |
| Download: ML17309A122 (44) | |
Text
~QC'9-S ER GAS >HO:
CTRlt TORPOR>'lOR
', -'; gv-g'r January 28, 1981 Director of Nuclear Reactor Regulation Attention:
Mr. Dennis M. Crutchfield, Chief Operating Reactors Branch N5 U.S. Nuclear Regulatory Commission Washington, D.C.
20555
Subject:
SEP Topics 'II-3.A, II-3.B, II-3.C, "Hydrology Review" R.
E. Ginna Nuclear Power Plant Docket No. 50-244
Dear Mr. Crutchfield:
Enclosed are the Rochester Gas and Electric comments regarding the NRC assessment of SEP Topics II-3.A, II-3.B, and II-3.C, "Hydrology Review" which was transmitted to us by letter dated December'2, 1980.
Note that an RG&E inspection of the revetment disclosed no degradation, although a more detailed inspection will be performed when weather and conditions permit.
Very truly yours, J.'.
Maier JEM:ng Attachments g.l pypgp.40
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Enclosure:
RG&E responses to NRC Evaluation of SEP Topics II-3.A, II-3.B, II-3.C, "Hydrology, Flooding, and Ultimate Heat Sink" g ))nb'.
In Section 3.1 of the assessment, it is noted that the significance of the local flood level (254.5 ft.) will be reviewed under the DBE's or one of the topics discussed in Section 1.0.
- However, since it is stated (correctly), in Section 2.0 that the safety related equipment at 253.5 feet msl (Service Water
- Pumps, buses 17 and 18, and the diesel generators) are protected by elevations of at least 16
- inches, there should be no need for further review.
Protection for-this local flood level is provided.
In Section 3.1, it would be useful to reference the basis for assuming a 13e9 acre drainage area.
In Section 3.2, the PMF flow of 37,500 cfs obtained for Deer Creek is simply staggering.
This flow, for a creek with a drainage area of 13.3 square miles, is 70% of the maximum estimated
~ow for the Genesee River, which has a drainage area of over 2,600 square miles.
4
~
5.
The information provided in the evaluation noted that a
100-year flood at Deer Creek would produce a peak discharge of about 3000 cfs, and that a flow in Deer Creek of 14,000 cfs would not result in the overflooding of any safety related equipment.
The margin shown in these values is considered sufficient to demonstrate that 'no danger from the PMF exists, and that this topic can be considered completed (with no required modifications).
In Section 3.2 additional references are required to determine the basis for a) the NRC analysis verifying that 14,000 cfs is an acceptable Deer Creek flow, and b) the 100-year flood estimate by the U.S.G.S.
In Section 3.3.0, it is stated by the NRC that visual observations during the SEP site visit indicated that the revetment fronting the plant on the west side of the discharge canal is significantly degraded.
During recent tel'ephone conversations between RG&E and the NRC staff (Ted.Johnson, Gary Staley, and Drew Persinko),
RG&E explained that no observable degradation of the revetment is apparent.
Ice and snow make it impossible to perform a detailed study.
- However, as soon as weather and conditions permit, RG&E will make an inspection of the breakwall (accompanied by the
- NRC, if so desired).
RG&E will make any modifications necessary to bring the breakwall to the original design conditions.
The design basis groundwater level was supplied by telephone to the NRC in November, 1978.
To document this information, attached is an RGaE interoffice memo regarding this subject.
As suggested in the topic assessment, the design basis groundwater level is at grade (253.5 ft.).
A summary and conclusions section should be added to the assessment, noting that the Ginna design meets the guidance presented in Standard Review Plan Sections 2.4.1, e'tc.
and Regulatory Guides 1.XX, with certain exceptions.
Based on the responses provided in this letter, the acceptability of these deviations should also be stated.
It is not clear what the intent of Section 2.0 of SEP Topic Assessment II-3.C is.
No references, design criteria, or acceptance criteria are provided.
No reference to the newly-constructed essential service water discharge (into Deer Creek) is made.
Additional NRC input is needed for RG&E to provide comments on the assessment.
Rochester Gas and Electric Corporation Inter-OfFice Correspondence November 21, 1978
SUBJECT:
Review of SEP Report Produced By The NRC TO:
R.C.
Mecredy Outlined below is a list of items that should be revised or amended in the notes produced by the NRC in relation to hydrological engineering.
A.
Page 2, item 3, second sentence to be revised as follows--The 6'X8'ntake is used for tempering ice effects in the screenhouse.
Additional information to be provided to the NRC is noted below:
1.
topographic maps of the plant area - supplied to G. Wrobel on September 14, 1978.
2.
design basis groundwater level (DBGWL) for all plant structures-C. Mambretti has obtained this information from Gilberts for all plant structures they originally designed.
The screenhouse/ESW structure was designed for a D.B.G.W.L. at finished grade (ELEV. 253.5').
Gary Goetz GG:np xc:
J.
Covey G. Wrobel '+
,C. Mambret"i
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 MAR 3
)8gt MEMORANDUM FOR:
William Russell, Chief Systematic Evaluation Program Branch Division of Licensing THRV:
i ~
ames P. Knight, Assistant Director for Components and Structures Engineering Division of Engineering I
FROM:
George Lear, Chief Hydrologic and'eotechnical Engineering Branch Division of Engineering
SUBJECT:
i
RESPONSE
TO ROCHESTER GAS AND ELECTRIC COMMENTS ON SEP TOPICS II-3.A, II-3.B AND II-3.C Attached are the suggested Hydrologic Engineering Section responses to comments by Rochester Gas and Electric Company on the hydrologic review for Topics II-3.A, B and C.
Based on the information contained in the I'.censees'omments it appears that he may not have a firm understanding of how SEP is supposed to work, especially with regard to the integrated assessment.
His comments indicate the desire to show acceptability of many items that require further coordination and assessment of safety significance.
It also appears that the licensee may not have a good understanding of hydrologic phenomena as evidenced by his comparison of a Probable Maximum Flood to a flood that has a recurrence interval of about 100 years.
Should this be the case, the licensee may be well advised to retain a competent Hydrologic Engineering Consultant to assist in this area of the SEP review.
, With respect to comment 7, we agree that a sumary and conclusion section should be added but it would be preferable to resolve the Deer Creek flood level first and then include input from structural and system reviewers.
Due to the unavailability of quality data the staff's Deer Creek flood analysis was very conservative.
We had anticipated that the licensee may choose to obtain the data necessary to do a more accurate analysis for Deer Creek.
In lieu of a refined analysis by the licensee we will use the conservative results of our analysis.
Your system and structural reviewers should be instructed to base their reviews on the current report and furnish input to the Hydrologic Engineering Section for inclusion in a Summary and Conclusions Section.
'I
Wi 1 1 iam Russell MAR 3 1981 The Hydrologic Engineering Section contact for these toPics is Gary B.
Staley at 492-8141.
Original signed bY Geo g d'or arear
Enclosure:
As stated George Lear, Chief Hydrologic and Geotechnical Engineering Branch Division of Engineering cc:
M. Fliegel
'. Staley D. Persinko H. Levin SEP Section Leaders L. Heller orrlCr)
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Hydrologic Engineering Sect>on Responses to Rochester Gas and Electric Comments on SEP Topics II-3.A, II-3.B, and II-3.C 1.
This res ons ponse should come from a system reviewer.
If the flood does not affect the lant p
or plant systems then a statement to that effect will be
~
added to the Safety Evaluation.
"RE GI 2.
Drawing titled, RE GINNA Plot Plan,"
Redrawn 3/3/79, Dwng Ho. 33013-352, was used to measure the drainage area.
3.
Ho bases have bee n provided for the licensees'tatements.
Using the Generalized PMF curves urves in Regulatory Guide 1.59, we estimated the PMF to be 500 000 ccfs for the 2600 S.M. Genesee River Basin.
The 37,500 cfs estimate for the Deer Creek PMF is 7.4X of th 500 00 e
0 cfs value, not 705.
The Deer Creek PMF is about 69K of the estimated maximum historical flow
- of the Genesee River (54,000 cfs on March 18, 1965).
This flow can be considered to be a very rough estimate of the 100 year flood on the Genesee River and as such should be compared to our estimated 100 year flood for Deer Creek.
The Deer Creek 100 year flood is about 5.6X of this maximum historical flood in the Genesee Riv Th 1'ver.
e icensee has provided no documentation or bases to shoow that the Deer Creek PMF is less than 37,500 cfs or that only 1100 cfs or less will flow across plant grade during a PMF on Deer Creek.,
Therefore our position remains that under current criteria the plant would have to be protected against an 8.0 foot depth of water resulting from the PMF on Deer Creek.
If the licensee has an analysis that shows a Deer Creek PMF considerably less than 37,500 cfs, it should be submitted to NRC for review and approval.
Our evaluation could then be revised accordingly.
4.
(a) Our conservative analysis was accomplished by developing rating curves for (1) the area south of the plant where the flow leaves Deer Creek to flow across the plant yard and (2) for the main Deer Creek channel..
The discharge of 1100 cfs was established'y~ising the discharge channel wall as a weir and backing flow across the plant yard until the limiting elevation of 254.25 was attained (1100 cfs).
Using the rating l
i curve from item (1) and the 1100 cfs, a water elevation'was obtained; this elevation was then applied to the Deer Creek rating curve to obtain the corresponding discharge of 14,000 cfs.
(b) The Albany, NY office of the USGS was contacted on January 16, 1979.
The office furnished draft formulae for computing the 2, 25, 50 and 100 year discharges for Western New York.
They stressed that they were in draft form and not approved.
As pointed out in our report the frequency data was for information purposes only and primarily for NRC management as a decision making'ool.
5.
No response required.
6.
The report will be corrected to include the groundwater information.
7.
This cannot be done until system and structural reviewers have assessed the effects of flood levels and the revetment is repaired.
"8.
There is no special criteria for the Systematic Evaluation Program and the current criteria is defined on page ll.
The report states (implies) that the water supply is acceptable with respect to availability but that flooding must be resolved.
Input from the interface topf'cs can not be included until the topic reviews are completed.
The report will be modified to show that the water supply and temperature are adequate to meet the requirements of Regulatory Guide 1.27 and therefore acceptable.
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Docket No. 50-244 LS05 04-01 3 P
UNiTED STATES NUCLEAR REGULATORY COMMlSSlON WASHINGTON, D. C. 20555 April 10, 1981 Mr. John E. Maier Yice President Electric and Steam Production Rochester Gas and Electric Corporation Rochester, New York 14649
Dear Mr. Maier:
SUBJECT:
SEP TOPICS II-3A "Hydrologic Description" II-3B "Flooding Potential and Protection Requirements" II-3.81 "Capability of OperatiTig Plants to Cope With Design Basis Flooding Conditions" II-3C "Safety-Related Mater Supply (Ultimate Heat Sink (UHS))
I)
Il Enclosure 1 is a copy of our evaluation of Systematic Evaluation Program Topics II-3A, B, C.
This assessment compares your facility, as described in Docket No. 50-244 and associated submittals, with criteria currently used by the regulatory staff for licensing new facilities.
Please inform us if your as-built facility differs from the licensing basis assumed in our assessment.
Enclosure 2 contains our responses to the additional information you have provided to us.
Following exchanges between the NRC staff and your staff, we have revised the evaluation to reflect this additional information.
In some cases you have not provided a technical basis for us to alter our con-clusions.
Therefore, our review of these topics is complete and this evaluation will be a basic input to the integrated safety assessment for your facility unless you identify changes needed to reflect the.as-built conditions.
This topic assessment may be revised in the future if your facility design is changed, if NRC criteria relating to these topics are modified before the integrated assessment is completed or if additional information is provided to the staff.
Enclosure 3 is a draft evaluation of Topic II-3.Bl.
You are requested to reexamine the facts upon which the staff has based its evaluation and respond either by confirming that the facts are correct, or by identifying errors and
\\
John E. Haier supplying the corrected information.
We encourage you to supply any other material that might affect the staff's evaluation of this topic or be signifi-cant in the integrated assessment of your facility.
Your response is requested within 30 days of receipt of this letter.
If no response is received-within.
that time, we will assume that you have no comments or corrections.
Sincerely,
Enclosure:
As stated nnss H. Crutchfsel ief Operating Reactors Bran Division of Licensing CC:
See next page
e fh g
Nr. 8ohn E. Naier CC Harry H. Voigt, Esquire
- LeBoeuf, Lamb, Leiby and NacRae 1333 New Hampshire
- Avenue, N.
W.
Suite 1100 Washington, D. C.
20036 Nr. Michael Slade 12 Trailwood Circle Rochester, New, York 14618 Ezra Bialik Assistant Attorney General Environmental Protection Bureau New York State Department of Law 2 World Trade Center New York, New York 10047 Jeffrey Cohen New York State Energy Office Swan Street Building Core 1, Second Floor Empire State Plaza
- Albany, New York 12223 Director, Technical Development Programs State of New York Energy Office Agency Building 2 Empire State Plaza
- Albany, New York 12223 Rochester Public Library 115 South Avenue Rochester, New York 14604 Supervisor of the Town of Ontari o 107 Ridge Road West
- Ontario, New York 14519 Resident Inspector R. E. Ginna Plant c/o U. S.
NRC 1503 Lake Road
- Ontario, New York 14519 Director, Criteria and Standards Division Office of Radiation Programs (ANR-460)
-U. S. Environmental Protection Agency Washington, D. C.
20460 U. S.
En vi ronmenta 1
P rotect i on Agency
'egion II Office ATTN:
EIS COORDINATOR 26 Federal Plaza New York, New York 10007 Herbert Grossman, 'Esq-,
Chairman
'tomic Safety and Licensing Board U. S. Nuclear Regulatory Commission Washington, D. C.
20555 I
Dr. Richard F. Cole Atomic Safety and Licensing Board U. S. Nuclear Regulatory Commission Washington, D. C.
20555 Dr.
Emmeth A. Luebke Atomic Safety and Licensing Board U. S. Nuclear Regulatory Commission Washington, D. C.
20555 Nr. Thomas B. Cochran Natural Resources Defense Council, Inc.
1725 I Street, N.
W.
. Suite 600
. Washington, D. C.
20006 Ezra I. Bialik Assistant Attorney General Environmental Protection Bureau New York State Department of Lair 2 World Trade Center New York, New York 10047
~
~
TOPIC II-3.A AND B HYDROLOGIC DESCRIPTION AND FLOODING POTENTIAL AND PROTECT ION REQUIREMENTS
- 1. 0 INTRODUCTION This topic encompasses both surface and groundwater and their interface with plant safety-related buildings and systems.
It provides a brief description of the hydrologic features of the site ard surrounding area.
A Design Basis Flood for the plant is developed, using current criteria, and compared to the design basis event that was used for construction, if any.
Deviations and their safety significance are discussed.
In addition to an external Design Basi: Flood (off site source),
a local Probable Maximum Flood resulting from Probable Maximum Prei.'ipitation on the plant area is also developed to determine flood potential from the local runoff.
>Jhere physical protection is used to prevent plant flooding, its design and design bases are reviewed and compared to current criteria.
The variations, if any, and safety significance of the variations are discussed.
The. Design Basis Groundwater Level is determined in accordance with current criteria.
Permanent Dewatering Systems (underdrains) are identified.
The eva1uation oi. underdrains is described in Topic III-3.B.
The information used to perform the reviews was gathered from the licensee's s
- files, NRC files, and the site visit.
In some cases, detailed information was not available.
In such cases, the staff conservatively estimated any parameters required for analysis.
The current criteria applicable to this topic are:
(1) Standard Review Plans 2.4.1, 2.4.2, 2.4.3, 2.4.5, 2.4.7, 2.4.8, 2.4.10, 2.4.11, 2.4.13, 2.4.14, 3.4.1 and 9.2.5; (2) Regulatory Guides 1.102, 1.127, 1.27, 1.59, and 1.70; and
. (3) American National Standard Institute Standard N170-1976.
Regulatory Guides 1.59 and 1.102 have been specifically identified by the NRC's Regulatory Requirements Review Committee as needing consideration for back-fit on operating reactors.
These guides are utilized in determining whether the facility design ccmplies with current criteria or has some equivalent alternatives acceptable to the staff.
The acceptability or'onacceptability of any deviations identified in this evaluation.and the need for further action will be judged during the integrated assessment for this facility.
This output from these analyses include groundwater and surface water levels and associated loadings for safety related buildings agd equipment.
These values are furnished to structural and system reviewers for assessment of effects.
Interface topics are:
(1) II-4E Dam Integrity; (2) III-3.A Effects of High
~Water Level on Structures; (3) III-3.B Structural and Other Consequences
(
(e.g.,
Flooding of Safety-Related Equipment in Basements) of Failure of Underdrain-Systems; (4) III-6 Seismic Design Considerations; (5) YII-3 Systems Required for Safe Shutdown; (6) VIII-2 Onsite Emergency Power Systems - Diesel Generator; (7) IX-3 Station Service and Cooling Water Systems; and (8) XYI Technical Specifications.
The category of "In Service Inspection'of Water Control Structures" requires hydrologic review and input; however, the hydro'logic aspects are addressed in Topic III-3.C.
- 2. 0 HYDROLOGIC. DESCRIPTION Lake Ontario, on which the site is located, is about 190 miles long, 50 miles
- wide, a maximum of 780 feet deep and covers an area of about 7500 square miles.
The:.verage lake level, based on over a hundred years of record, is 246 feet msl.
~
~
3 The highest instantaneous still water lake level was 250.2 feet msl.
Lake Ontario seldom freezes over, but ice occurs in the winter usually along the 1
southern and northern shores and in the northeastern end of the lake.
The surface of the land on the southern shore of Lake Ontario, at the site and east and west of it, is either flat or gently roll-ing as shov(n on Figure 2.0.1.
It slopes upward to the south from an elevation of about 255 feet msl near the edge of the lake to 440 feet msl at Ridge'Road (New York State Highway 104) 3 1/2 miles south of the lake.
There are no perennial streams on the site, but Oeer Creek, an intermittent l<~ F~i stream with a drainage area of abouts square miles, enters the site from the l
- west, passes south of the plant and empties into the lake near the northeastern corner of the site.
The main plant area and buildings are at grade elevation 270.0 feet msl l the north side of the turbine building and the river screenhouse are at elevation 253.5 feet msl.
The plant is protected from surges and wind. driven waves by a revetment with a top elevation of 261.0 feet msl.
All facilities necessary to shut down and to maintain safe shutdown are flood-protected to a maximum still water level of 254.25 feet msl.
The screenhouse floor is at elevation 253.5 feet.msl and the 0.75 foot curbs provide additional protection from pote'ntial exterior flooding.
Additional flood protection is available. in the screenhouse for the diesel generator
- buses, which are set 16 inches
above the floor, and the service water pump motors which are set 24 inches above the floor.
The diesel generators, which are located in the north side of the turbine building, are flood protected by steel curbs projecting 18 inches above elevation 253.5 feet msl.
3.0 FLOOD POTENTIAL AND PROTECTION RE UIREMENTS
. Independent estimates were made of the flood levels which would occur at safety related buildings, assuming an occurrence of the local
~CM v'robable Maximum Precipitation (PMP).
Rainfall was assumed to occur in the immediate plant area and the resultino flow (runoff) moved I
overland toward the discharge canal.
Rainfall depths were: obtained from Hydrometeorological Report No. 51,
'for the 13.9 acre drainage (a) area.
The time of concentration and peak discharge of 400 cf were computed with methods described in Design of Small Dams.
The flood (5) water will pond to an elevation of about 254.5 feet msl at the north (lower) portion of the site in the vicinity of the screen house.
3.2 Deer Creek PMF r
The water levels produced by a Probable Maximum Flood (PMF) on Deer Creek, a small stream which, under normal conditions flows north and eastward I
around the Ginna site, were evaluated.
The drainage area of Deer Creek is 13.3 square miles.
The Probable Maximum Precipitation (PMP)
was obtained from reference (4).
The runof hydrograph was developed using procedures from reference (5) and backwater computations were made using the HEC-2 Backwater Program (6).
Cross sections for the backwater ccmputations were taken from drawing Ho.
SK447-93.
The PMF flow of 37,500 cfs would produce a water surface elevation of l
about 275 ft msl on the south: (higher) side of.the plant.
Since plant grade in this area is elevation 271.0 ft msl, flood water will flow over the plant yard toward the screenhouse and discharge channel at a rate of about 13,500 cfs.
The discharge canal does not have sufficient capacity to discharge this flow.
Mater will pond to a depth of about eight feet over plant grade in this area of the plant.
Safety related equipment is protected to a depth of only 0.75 to 2.0 feet.
Further analysis has revealed that elevation 254.25 would not be exceeded if the flow in Deer Creek did not exceed 14,000 cfs, of which 1100 cfs flows overland toward the screenhouse and discharge channel.
For informational purposes only, the 100-year flood on Deer Creek would produce a peak discharge of about 3000 cfs, based on regional estimates
'ecently developed by the U. S. Geological Survey.
V 3.2.1 Availabilit of Safet S stems It must be emphasized that there will be little, if any, warning time before the plant is flooded by a PHF on Deer Creek due to short times of concentration of flood flows.
Therefore, credit should not be given for h
implementation of temporary flood-proofing measures to protect safety systems.
- Rather, permanent flood protection appears to be the best measure for protecting the plant.
3.2.2 Probabilit of Initiatin Events 4'"
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The PNF estimate was calculated using a deterministic method of analysis, wherein various flood-producing parameters were maximized to produce the C
most, severe lood considered reasonably probable in She region.
No statistical analyses were used by the NRC staff to determine these parameters.
Me therefore believe that no attempt can or should be made to assign a probability to the PHF for Deer Creek.
3.2.3 Past Plant Ex erience Plant personnel have stated that no serious floods have occurred on Deer Creek during the operating life of the plant.
3.3.0 Lake Ontario Surae Floodin Visual observations during the SEP site visit-indicate the revetment fronting
.the plant on. the west side of the discharge canal is significantly degraded.
Portions of. the revetment would be incapable of providing adequate protection from wave attack during a severe storm',
up to and including the Probable Maximum Mater Level (PHWL), resulting from the Probable tlaximum Surge (PV5)
I h
&7 on Lake Ontario which is the design basis flood for the revetment.
It is not possible at this time, due to a lack of information regarding revetment geometry and stone sizes, to determine the exact water levels and wave heights for which the existing protection will function. If the revetment is assumed to be eroded significantly (as it apparently is), and the design-basis storm occurs, we calculate that about 2.5 feet of water would be ponded in the vicinity of the screen house and discharge canal, which would exceed the elevation of the emergency buses and be about the same elevation as the eight service water pump motors.
I'Q!
We have,
- however, performed an independent
- analysis, using procedures from the Shore Protection Manual, of the stability of the revetment (7)
I assuming it exists as designed.
We find that, under these conditions, the revetment would be capable of resisting the Lake Ontario PMl<L and a'ssociated wave action and wou1d, therefore, meet current regulatory criteria.
As a condition of the FTOL, the staff required the placement of additional shoreline erosion protection.
This protection was added to ensure minimum wave overtopping of the concrete wall fronting the plant and lower water levels in the vicinity of the screen house.
Nevertheless, the revetment, as it currently exists, would likely fail during an occurance of. the PHWL.
This failure would likely lead to a subsequent fai lur'e of the additional, protection installed as a requirement of the FTOL.
We, therefore, recommend that damaged or inadequate portions of the revetment be repaired and returned to design conditions.
The repairs should be performed as soon as the weather permits.
In addition, we recommend that a technical specification be developed and implemented to provide for maintenance of the revetment as designed.
1
4.0 Desi n Basis Groundwater Levels The design basis groundwater elevation for the Screenhouse/ESW structure was 253.5 feet HSL and the design basis for all other safety related structures was elevation 250.0 feet HSL (Ref. Letter RGE to DRC November 14, 1979; Letter RGE to NRC January 28, 1981).
/
The design basis under current criteria should be ground elevation at the structure in question.
This will vary from elevation 253.5 feet HSL on the north side of the plant to about elevation 270.0 feet HSL on the south side.
No groundwater contour map's or we'l hydro-graphs have been submitted to justify using a lower groundwater level.
0
5.0 Conclusions 5.1
~L1 F1 di It is concluded that flood water will pond to an elevation of about 254.5 feet HSL at the north area of the site in the vicinity of the screenhouse.
As a result of RGE's response number one in the submittal dated 1/28/81, it is concluded that the statements in the Ginna FSAR 2;6-,10 are still valid and the paragraphs on pages 3 and 4 of the Topic II-3A, B, C evaluation regarding limit-ing equipment elevations are correct.
Per the Ginna FSAR 2.6-10, the limiting elevation for'lass I equipment -is elevation 253.5 (screenhouse floor elevation).
Adding 0.75 feet for curbs around h
the screenhouse floor provides protection to elevation" 254.25.
This is still below the predicted local flood level; however, the licensee has verified that the limiting elevation of safety-related equipment is 254.8 feet MSL (screenhouse floor elevation of 253.5 plus 1.3'o diesel generator buses 17, 18).
Therefore, safety related equipment would be unaffected by local floods, and the plant would be able to with-stand local flooding with no detrimental effects.
5.2 Deer Creek PHF The PMF will cause a water surface elevation of about 275'eet MSL on the south side of the plant where grade is approximately 271 feet HSL.
On the north side of the plant where grade is approximately 253.5,. feet HSL, the PMF will cause water to pond approximately eight feet::above grade.
This would lead to unacceptable consequences to pla'nt systems in the auxiliary and diesel generator buildings due to in-leakage.
The ability of plant structures to withstand this water level is considered in Topic III-3A.
g>>
Cl
-ga-5.3 Lake Ontario Sur e Floodin The plant is protected by a revetment fronting Lake Ontario.
Signifi-
. cant erosion of the revetment was noted during the site visit.
Assum-ing that the revetment is eroded, approximately 2.5 feet of water will pond in the vicinity of the screenhouse submerging the emergency buses.
If the revetment exists as designed, it would be capable of resisting surge flooding from Lake Ontario and therefore meet current regulatory criteria.
The licensee has agreed to inspect the revetment for erosion and return it to its original design condition.
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6.0 REFERENCES
- 1. Standard Review Plans, NUREG 75/087, U. S. Nuclear Regulatory Comnission, Office of Nuclear Reactor Regulation.
a ~
b.
C.
d.
e.f.
9.
h.i.
k.l.
2.4.1-2.4.2-2.4.3-2.4.5-2.4.7-2.4.8-2.4.10-2.4.11-2.4.13-2.4.14'-
3.4.1-9.2.5-Hydrologic Description Floods Probable Maximum Flood (PMF) on Streams and Rivers.
Probable Maximum Surge and Seiche Flooding Ice Effects Cooling Water Canals and Reservoirs Fl ooding Protection Requirements Low Mater Considerations Groundwater Technical Specifications and Emergency Operation Requirements Flood Protection Ultimate Heat Sink 2.
Regulatory Guides, U.S. Nuclear Regulatory Comnission, Office of Standards Development.
a.
b.
C.
d.
e.
1.102 - Flood Protection for Nuclear Power Plants 1.127 - Inspection of Water Control Struc.ures Associated with Nuclear Power Plants l
1.27
- Ultimate Heat Sink for Nuclear Power Plants 1.59 Design Basis Floods for Nuclear Power Plants 1.70
- Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, NUREG-75/094 3.
American National Standard N170-1976, "Standards for Determining Design Basis Flooding at Power Reactor Sites,"
Published by the American Nuclear Society (ANS-2.8) 4.
U.
S.
Department of Conrnerce, Nat'ional Oceanic and Atmospheric Administrati,on - U.S. Department of the Army Corps of Engineers, Hydro-meteorological Report No, 51, June
- 1978, "Probable Maximum Precipitation Extimates:
United States East of the 105th Meridian."
5.
U.S. Department of Interior, Bureau of Peclamation, 1977,"Design of Small Dams."
6.
U.S.
Army Corps of Engineers Hydrologic Engineering
- Center, February
- 1972, "Water Surface Profiles (HEC-2) Users Manual."
7.
U.S.
Army Coastal Engineering Research
- Center, 1977, "Shore Protection Manual."
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TOPIC II-3.C.
SAFETY RELATED MATER SUPP'
{UHS)
- 1. 0 INTRODUCTION This topic'reviews the acceptability of' particular feature of the cooling water system,
- namely, the Ultimate Heat Sink (UHS).
The review is based on. current criteria contained in Regulatory Guide 1.27
{Rev. 2) which is an interpretation of General Design Criteria 44, "Cooling Mater" and General Design Criteria 2, "Design Bases for Protection Against Natural Phenomena,"
of Appendix A to 10 CFR Part 50.
This regulatory guide has been specifically identified by the NRC's Regulatory Requirements Review Commit ee as needing consideration
't for backfit on operating reactors.
This guide is'til'ized i'n determining whether the facility design complies with current criteria or has some equivalent alternatives acceptable to the staff; The acceptability or non-acceptability of k
c any deviations identified in this evaluation and the need for furth'er action will be judged during the integrated assessment for this facility.
In addition to Regulatory Guide 1.27, guid'ance is also contained in:
Standard Review Plans 2.4.11. and 9.2.5, American National Standards Institute Standard N170-1976, and Regulatory Guides 1.59 and 1.127.
t The UHS as reviewed under this topic is that complex of water sources, including necessary retaining structures (e.g.,
a pond with its dam or a cooling tower supply basin) and the canals or conduits connecting the source with but not including, the cooling water system intake structures.
This topic interfaces with Topic numbers II-3.B, III-l, III-3.A, III-3.B, III-3.f III-6, VI-7.D, VII-3, VII-4, VIII-2, IX-3, XV-24, and XVI, for the review of structures containing the safety related wa.er supply system, the systems themselves and emergency electrical power.
2.0 Ultimate Heat Sink UHS The ultimate heat sink for the Ginna Plant is Lake Ontario.
The inlet crib for the plant is on the lake floor about 3000 feet offshore.
Hater is conveyed from the crib to the Screenhouse (intake structure) through a buried conduit.
The circulating and service water pumps are located in the screenhouse.
The minimum mean monthly lake level of record for Lake Ontario at the Rochester, NY gage is elevation 243.0 ft. msl.
The lowest entrance level into the intake crib is elevation-.217.0 ft msl.
This 26 foot (243.0-217.0) depth of water at minimum lake level is more than adequate to accommodate the maximum setdown (negative surge) for this part of the lake which is less than I
l 5.0 feet.
Lake Ontario meets the current regulatory criteria with regard to low water requirements.
The consideration of design basis temperature for safety-related equipment is only required where the supply may be limited or where the temperature of plant intake water from the sink may eventually become critical (e. g.,
- Ponds, small lakes, cooling towers or other sinks where recirculation between plant cooling water discharge and intake can occur).
This is not a consideration for the Ginna Plant and Lake Ontario because the intake water is withdrawn from the bottom of the lake and the water temperature of this large lake are relatively stable.
Based on our analyses, the ultimate heat sink complex would meet current regulatory criteria with regard to flooding except for an occurrence'f the probable Maximum Flood on Deer Creek.
Flooding at the screen house would inundate both the service water and circulating water pumps.
.The seismic capability of UHS structures and conveyances is being reviewed in Topic III-6.
Our review of the availability of cooling water from Lake Ontario indicates that it is an acceptable source for the safety related water supply and ultimate heat sink.
Enclosure 2
NRC Responses to Rochester Ggs and Electric Comments on SEP Topics II-3.A, II-3.B, and II-3.C (RGE submittal 1/28/81) 1.
The evaluation has been revised to reflect the plant's ability to resist local flooding.
2.
Drawing titled, "RE GINNA Plot Plan,"
Redrawn 3/3/79, Dwng No. 33013-352, was used to measure the drainage area.
3.
No bases have been provided for the licensees'tatements.
Using the Generalized PHF curves in Regulatory Guide 1.59; we estimated the PMF to be 500,000 cfs for the 2600 S.M.
Genesee River Basin.
The 37,500 cfs estimate for the Deer Creek PMF is 7.4Ã of the 500,000 cfs value, not 70K.
The Deer Creek PMF is about 69K of the estimated maximum historical flow of the Genesee River (54,000 cfs on March 18, 1965).
This flow can be considered to be a very rough estimate of the 100 year flood on the Genesee River and as such should be compared to our estimated 100 year flood for Deer Creek.
The Deer Creek 100 year flood is about 5.6X of this maximum historical flood in the Genesee River.
The licensee has~provided no documentation or bases to show that the Deer Creek PHF is less than 37,500'fs or that only 1100 cfs or less will flow across plant grade during a
PHF II on Deer Creek.
Therefore our positon remains that under current criteria the plant would have to be protected against an 8.0 foot depth of water
'/
resulting from the PHF on Deer Creek.
If the licensee has an analysis that shows a Deer Creek PHF considerably less than 37,500 cfs. it should be submitted to NRC for review and approval.
Our evaluation could then be revised accordingly.
e 4
6.
The report has been corrected to include the groundwater information.
7.
Conclusions have been added to the extent possible.
Com'piete con-clusions regarding flooding protection requirements cannot be made until the effects of flood levels on systems and structures have been addressed and the revetment is repaired.
8.
There is no special criteria for the Systematic Evaluation Program and the current criteria is defined on page 11.
The report states (implies) that the water supply is acceptable with respect to availability but that flooding must be resolved.
Input from the interface topics can not be included until the topic rev'iews are completed The 'report has been modified to show that the water supply and temperature are adequate to meet the requirements of Regulatory Guide 1.27 and therefore acceptable.
I,
Enclosure 3
SEP Safety Topic Evaluation.
Ginna Nuclear Power Station.
Topic II-3.B.1 - Capability of Operating Plants to Cope with Design Basis Flooding Conditions I.
INTRODUCTION One method of protecting a plant against postulated floods is by implementing appropriate technical specifications and emergency procedures.
This topic reviews existing technical specifications and emergency procedures to assure that the originally imposed technical specifications and emergency procedures can still adequately protect Category I structures, systems and components.
II.
CURRENT REVIEW CRITERIA Current review criteria are identified in Regulatory Guide 1.59, and Standard Review Plan Section 2.4.10.
III.
RELATED SAFETY TOPICS AND INTERFACES The following topics relate to Topic II-3.B.l:
l.
II-3A Hydrologic Description 2.
II-3B Flooding Potential and Protection Requirements 3.
III-3A Effects of High Water Level on Structures.
V.
EVALUA1ION There are no existing emergency plans or Technical Specifications for the Ginna Plant that relate to flooding from external sources.
The determination of need to install emergency plans or Technical Specificationsas a result of revised design bases flood levels will be made during the integrated assessment of the plant.