ML20198G668
| ML20198G668 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 04/23/1975 |
| From: | Harold Denton Office of Nuclear Reactor Regulation |
| To: | Moore V Office of Nuclear Reactor Regulation |
| References | |
| CON-WNP-1061 NUDOCS 8605290726 | |
| Download: ML20198G668 (19) | |
Text
4 t
i i
I APR 2 319?S i
i i
V. A. boore, Assistant Director for L'.iR, Group 2. DRL I
REVISEDliYDROLOGICEtGIfiEERINGSumARY(SER)
Pi.A!(I HNiE: WPPSS Nuclear Projects 1 & 4 3
l LICEllSIllG STAGE: CP_
DOCKET i4Jt3ERS- $0-460/513 l
RESPONSIBLE 24 i
REQUESTED COMPLETI0!! DATE: fl/A REVIEW STATUS:
Hydrologic Engineering Section, SAB - Waiting Infomation From the Applicant i
Enclosed is a second revision to the hydrologic engineering sumary on the subject plant, prepared by G. B. Staley and E. Hawkins. This re-vision resolves our last open item which was excess temperatures on the ultimate heat sink spray pond. However, the applicant has infomed us that they will either have to revise their equipment designs or the spray pond design as they have an incompatability between the maximum pond temperatures and current equipment design. The applicant has stated that new infomation will be submitted for our review. Our evaluation of the applicants revisions will be reported in a supplement to the SER.
odg>st siped by N. R. Denten Harold R. Denton, Assistant Director for Site Safety Division of Technical Review Office of fluclear Reactor Regt0ation
Enclosure:
As stated cc: w/o encl:
A. Giambusso U. ficDonald J. Panzarella l
cc: See attached page l
l l
i e
i 8605290726 750423 one. *
- PDR ADOCK 05000460 E
PDR DAT D l
- ......... _............... Z..~.... -
~
~
- r.. u c.n.
,n u m m.
4 APR 2 3 575 V. A. Moore '
i
'r cc: w/ encl:
I S: Hanauer R. Klecker I
F. Schroeder D. Eisenhut H. R. Denton S. Varga SS Branch Chiefs C. Long A. Kenneke G. Staley A. Schwencer L. Shao l'
T. Xox V. Benamya i
Distribution:
Central File i
NRR:RDG NRR:SAB f
i f
I I
v10
- ~,.
l a ic = *
..IR:SAB.
_.TR:S
- _/pdA
- TR Ah j
,,[2,8,,9, GStaley/joc LGHu WPGarpniYl1 HRD on
~
i 4/4[./75 4/21/75 4/ss /75 4/ 2,2,/75
.A oavs >
t Foran ABC 31e (Rev. 9 5)) AECM 0240 W u. e. oovannasant ensurine orrics ie74.eae. se
4 REVISED HYDROLOGIC ENGINEERING SU>DfARY WASHINGTON PUBLIC POWER SUPPLY SYSTEM NUCLEAR PR'0JECTS 1 & 4 DOCKET NO. 50-460/513 2.4. HYDROLOGIC ENGINEERING 2.4.1.
HYDROLOGIC DESCRIPTION The site for Washington Public Power Supply System (WPPSS) Nuclear Projects one and four (the plant) is located in the southeast area of the Hanford Reservation in Benton County, Washington, 8 miles north of the city limits of Richland, about 2.5 miles west of the Columbia river at river mile 352 and 45 miles downstream frem the Grant County Public Utilities District Priest Rapids Dam. The Columbia River is th'e predominant hydrologic feature of the area and provides the principle drainage for the site and surrounding area. The Columbia River, upstream of the plant site, has a drainage area of about 97,000 square miles. The major tributary upstream of the site is the Wenatchee River. The Snake and Yakima River enter the Columbia River just downstream of the site. Regulation of the Columbia River by dams and reservoirs has been extensive over the past 35 years.
A large portion of the main stream and major tributaries is developed to 1
meet various functional requirements such as flood concrol, navigation, hydroelectric power, irrigation, and municipal and industrial water supply. The following Table 2.4.1 lists the dams on the Columbia River upstream of the site and dams on the tributaries above Grand Coulee Dam.
Table 2.4.2. lists tributary dams between Grand Coulee Dam and the plant site. The regulated average annual Columbia River flow at the site is 115,000 cfs. During the year the flow may vary upward from a regulated
TABLE 2.4.1
.[ ' -
UPSTREAM COLUMBIA RIVER DAMS
( AND ITS TRIBUTARIES ABOVE GRAND COULEE )
CREST GROSS USABLE LENGTH STORAGE STORAGE NAME OF DAM RIVER MILE TYPE HEIGHT (ft)
(1000 Acre-ft) (1000 Acre-ft)
(ft)
Priest Rapids 397 Concrete Gravity 100 10,137 200 170 5/
and earth fill Wanupum 416 Concrete Gravity 133 8,707 796 389 5/
and earth fill Rock Island 453 Concrete Gravity 73 3,800 5
Rocky Reach 474 concrete Gravity 140 2,900 390 120
& carth fill i
Wells 516
' Concrete Gravity 160 4,460 300 117
'& carth fill Chief Joseph 545 Concrete Gravity 205 4,383 518 Grand Coulee 598 Concrete Gravity 355 4,173 9,402 5200 Albeni Falls 90 2/
Concrete Gravity 66 1,055 1,560 1.153 Hungry Horse 5 6/
Concrete Arch 520 2,115
'3,468 3,160 Kerr Dam 77 J/
Concrete Arch 186 800 1,226 1,219 Arrow 1/
781 Concrete Gravity 170 7,090
& earth fill 12,000 Mica 1/
1018 Rockfill 640 e
O
TABLE 2.4.1 (CONTINUED)
UP,9TREAM COLUMBIA RIVER DAMS
~
.( AND' 1T5 TRIBUTARIES ABOVE GRAND COULEE )
- CREST GROSS USABLE NAME OF DAM RIVER MILE TYPE HEIGHT LENGTH STORAGE STORACE (f.t)
(ft)
(1000 Acre-ft).(1000 Acre-ft)
Duncan 1/
8.3 3_/
Earthfill 130 1,400 Libby 220 4_/
Concrete Gravity 370 5,000 1/
These projects located in Canada are part of the Columbia River Treaty Storage as is Libby on the United States side.
2/ ' The river mile shown is on the Pend Oreille River, which joins the Columbia River at Columbia R. M. 745.5 3/
Duncan River Miles, Duncan River flows into Kootenai Lake in Canada.
4/
Kootenai River Miles, the Kootenai River joins the Columbia River at Columbia R. M. 774.1 5/
Not presently usable for flood regulation.
6_/
South Fo k Flathead River Miles.
7f Clark Fork River Miles.
e.
b
~
..l-
. TABLE 2.4.2
~
. TRIBUTARY DAMS LOCATED BETWEEN GRAND COULEE DAM AND PLANT SITE CREST GROSS
%AME OF DAM 1tIVER MILE TYPE HEIGHT LENGTH STORAGE l
(ft)
(ft)
(1000 A F)
"Chelan 3 6_/
Concrete 40 677
~
0 Sullivan 42 1,5/
Zoned earth fill 153 19,000 615.6 Billy Clapp 85 1,5/
Zoned ea'rth fill 130 1
~
Banks 99 1,5/
Zoned earth fill 123 762 Snow I.akes 31 2_/
Concrete Gravity 12 13 Conconully 48 3/
Hydraulic Earth 70 1000 13 Salmon Lake 49 3/
Zoned earth fill 42 1260 11 Owhi 16 4/
Earth fill 14 5
1/
The river mile shown is on Crab Creek.
Crab Creek enters the Columbia River at River Mile 4,11.
2_/
The river mile shown is upstream from the mouth of the Wenatchee River. The Wenatchee River enters the Columbia River at River Mile 468.
3_/
The river mile shown is upstream from the mouth of the Okanogan River. The Okanogan River enters the Columbia River at River Mile 533.
4/
The river mile shown is upstream from the mouth of the Nespelem River. The Nespelem River enters the Colunbia River at River Mile 582.
e e
TABLE 2.4.2 (CONTINUED)
J]
Part of the Columbia Basin Project and used s.91ely for stroage of irrigation water.
6/
The river mile shown is on the Chelan River. The Chelan, River joins the Columbia River at Columbia River Mile 503.3.
e J
e L
O 8
e I
S e
low of 36,000 cfs.
The main river channel near the site varies from 400 to 600 yards in width and in depth from about 30 feet for normal high water to about 45 feet or more for flood high water. The approximate river bottom elevation near the site is 328 feet above mean sea level datum (f t 1GL).
The ground elevation at the site is about 445 f t' MSL, and will. be raised ~ to an approximate elevation of 451 ft MSL. The lowest seismic Category I
~
structure will be at elevation 446 f t MSL.
At the present time there are no ground water users on either side of the river in the vicinity of the site. Ground water will be.used during plant construction at rates of between 950,000 and 4,200,000 gallons per month. There are 32 surface. water users with registered water rights in the 50 miles reach downstream of the site. Most of the users are withdrawing water for irrigation and industrial purposes.
There are three users, the cities c2 Richland and Pasco and one private individual, that withdraw water for domestic or municipal uses.
In addition, the city of Kennewick obtains its water indirectly from the river thru a system of Ranney collectors that draw both ground and river water. With exception of the river intake structure, all the structures are located about 2.5 miles west of the Columbia River. The river intake structure is to be on the west bank of the Columbia Rivec and is capable of supplying river make-l up water from river stages between elevations 342 and 373 ft MSL.
1 t,
2.4.2 FLOODING The largest flood recorded on the Hanford reach of the Columbia River occurred in 1948 and had an observed peak discharge of 690,000 cfs.
The largest known historical flood occurred on June 7, 1894, and had a peak discharge, estimated from high water marks, of 800,000 cfs.
~
There is no record of major faulting in the site area due to ice jams.
Ice blockage is most likely to occur when water temperaturas are already
~
low, when flows are small, and when a significant cold spell occurs.
With the completion of Grand Coulee and other dans on the Columbia River main stem, the seasonal temperature and flow cycles have been drastically altered.
These changes are coupled in such a way to reduce tha intensity and timing of the conditions which many contribute to a potential ice blockage and flooding situations. Average winter flow rates have increased, the low extreme temperatures have risen over the years, and water temperaturee have shown a shif t in time so that peak temperatures now occur 30-45 days later than formerly.
In tha event that ice blockage should occur, the potential for flooding can be greatiy reduced by controlled river release rates at the upstream dams.
It can be concluded from these observations and studies, and the recorded observations of 25 years of operation of the Hanford Production plants involving critical flows for nuclear safety, that the potential for ice blockage or the combination of blockage and flooding behind ice dams is so low as to be considered insignificant.
In any event, ice flooding will not be a major deterent to the make-up water pumphouse, and'it would not effect the capability to shut down the reactor in a safe and orderly manner because of the availability of the ultimate heat sink spray ponds at the site.
The applicant used an unregulated and regulated PMF developed by the U. S.
Army Corps of Endineers (1) (2)as the design basis precipitation flood for the site. The peak discharge for the unregulated EMF is 1,600,000 cfs and 1,440,000 cfs. for the regulated PMF. The predicted river elevation (based upon Corps of Engineers profiles) for these flows is 392.0 and 389.0 ft MSL respectively.
Since all safety related plant structures are at or above elevation 446.0 ft MSL, it is concluded that flooding due to a PMF has no significance to the safety of the plant.
The river intake structure is not a safety related structure.
The applicant has analyzed two types of storms to evaluate the effects of a local intense storm at the site.
The analysis produced a calculated Probable Maximum Precipitation (PMP) of 10.1 inches over a 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> period for a general storm and 9.2 inches of precipitation in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> for a thunderstorm. The applicant has analyzed the runoff from the PMP and has concluded that the chann,el west of the site will have sufficient slope and' capacity to convey these flood waters away from the site and that the highway and railroad will not have an adverse affect on the flood stages.
We have concluded that the applicant's analyses of site precipitation l
and subsequent runoff hydrograph are acceptable. The applicant has provided an acceptable design to preclude flooding through rcof penetrations on l'
safety related buildings. The applicant has also provided an acceptable design and analyses to insure that safety related buildings and equipment I
- Underlined portions indicate changed material
, will'not be flooded from runoff due to a local intense thunderstorm over the plant and contributing drainage area.
The applicant has used two studies by the Seattle District Corps of Engineers to define the potential river stage at the site due to a seismically induced dam failure of Grand Coulee Dam.
The results of these studies indicate that the flood would have a peak flow rate of 8,800,000 cfs at Grand Coulee Dam at the moment of breaking, and flow rate at the site, (including 400,000 cfs base flow) of 4,800,000 cfs.
This flow would produce a peak stage at the site estimated at 422.5 ft MSL. An additional fcot was added to account for a higher postulated Regulated Standard Project Flood (RSPF) of 570,000 cfs. One foot of stage was also added to account for wind wave activity for a total stage at the site of 424.5 f t MSL, which is 23.5 feet belew the grade level of the lowest safety related building. The analysis included the assumption that all reservoirs were full and that a partial failure occurred at all 1
l downstream reservoirs, causing a release of their pools to the flood.
The staff has reviewed this subject extensively for other reactor sites along the Columbia River.
From this conservative analysis it can be concluded that safety related facilities are safe from floods of this nature.
l l
L
. 1 2.4.3 Ultimate Heat Sink The Ultimate !! eat Sink (UHS) for the plant has two sources of water (1) the river intake structure, which is not a Seismic Category I structure;and (2) a 300 f t x 250 f t Seismic category i
I spray pond for each unit. The spray ponds are designed to provide a 30 day supply of water in the event of a loss of coolant accident (LOCA) and/or loss of offsite power (LOOP).
They must also provide'this water at a temperature less than the maximum allowabic for equipment operation.
The applicant used the following parameters or assumptions in his analyses of the UHS heat and water budgets.
1.
Percentage of heat rejected by spraying equals 80% (Ref.3). The range from Reference 3 was from 65% to 80%.
2.
Cooling efficiency of spray nozzles equals 40% (Ref.3.).
3.
Drift loss equals 0.8% (Ref.3).
4.
Wet bulb temperature equals 74*F for developing spray pond temperature response.
?
5.
The maximum evaporation rate was based on the maximum daily average dry bulb temperature of 91.8'F and the lowest monthly average rela-i l
tive humidity of 21.9% (Wet bulb temperature of 65'F) for the 30 day period.
These values were assumed to occur simultaneous 17,.with the highest drif t rate.
In addition there were some other conservatisms builc into the analysis as follows:
~
1.
During actual operation, the sprays will be bypassed when the temperature goes below 80*F.and until it goes ba'ck up to 85'F.
m
. 4 This is expected to save a significant amount of drift.
2.
A constant flow rate was used in the analysis but in actual operation flow rates will be controlled by the heat load. This should reduce
~ drift loss.
The only time that it will be necessary to depend solely on the pond water supply is when the riverintake capability is not available. Loss of the i
river water supply could be due to a seismic event, flooding, or low water due to ice blockage or drought. Flooding and low water due to ice blockage
'are discussed above in section 2.4.2 and low water due to drought is dis-cussed in the following section 2.4.4.
We have made an independent analysis of the UHS performance using the hydro-l dynamic ' and excess temperature analysis (HYETA) program (Ref. 4). The pro-gram has been modified by the staff to facilitate the evaluation of spray pond performance as defined in the Rancho Seco Report (Ref. 3). We computed a maxi-mum pond temperature of 1070F, which is less than the applicants reported maxi-0 mum value of 110 F.
Our analysis was based on a 25% nozzle array spray effi-ciency and a wind speed of 7.0 miles per hour. All other parameters were the same as presented in'the PSAR by the applicant. The staff aas been informed i-by the applicant that changes will be necessary to either:
(1) modify equip-l ment design to be compatible with the 110 F maximum return water temperature or, (2) modify the ultimate heat sink design to reduce the return water tempera-ture to an acceptable value for present equipment design. The applicant has
- Double underlined portion indicated changed material for this 2nd revision.
i 1
. stated that new information will be submitted for our review. We will review this new infomation under the same criteria as was used on the
, evaluation already completed. Our evaluation of the apolicants revisions will be reported in a supplement to this report.
2.4.4 LOW RIVER FLOW CONSIDERATIONS Reservoir projects in the Columbia River Basin upstream of the proposed site have a total usable storage in excess of 35 million acre-feet. This capacity alone is sufficient to maintain a flow in in the Columbia River, at the proximity of the plant, of 36,000 cfs for over one year with no inflow from other sources.
Because of this regulation, the antici-pated minimum and maximum monthly mean flow rates will be 60,000 and 260,000 cfs in the vicinity of the proposed site.
In the 18 years, since clo:ure of Priest Rapids Dam, the minimum flow rate has been 36,000 cfs.
It is concluded that it is improbable that the flows in the vicinity of the site will be less than the minimum regulated value of 36,000 cfs.
However, in the unlikely event that lower flows should occur, on an infrequent basis, they would not af'fect the safety of the plant since it can be brought to *a safe shutdown condition through use of the ultimate heat sink spray ponds.
l 2.4.5 GROUND WATER Three principal hydrologic zones underlie the Hanford Reservations as follows:
(1) Unconsolidated silts, sands, and gravesi (glaciofluviatile sediments).
l.
(2) Semiconsolidated lake and stream sediments (Ringold Formation) l (3) Dense, hard basalt which foms the bedrock beneath the area.
- Double underlined portion indicated changed material for this 2nd revision.
9 In general, ground water in the surficial sediments occurs under unconfined or water-table conditions. However, locally confined zones do exist in e
the area. Water in the basalt bedrock occurs mainly under confined conditions.
In some areas,'the lower zone of the Rin6 1d Formation is a confined aquifer, separated from the unconfined aquifer by thick clay beds and possessing a distinct hydraulic potential. The depth to the water table varies greatly from place to place depending chiefly on the local topography, ranging from less than 1 to more than 300 feet below the land surface. At the site the water table is from 72 to 85 feet below the land surface. The current estimate of the maximum saturated thickness of the unconfined aquifer is approximately 230 feet. From the proposed site, the groundwater flow is toward the discharge 1 undary at the Columbia River to the east of the site.
The hydraulic gradient in this area is about 10-13 feet / mile in the unconfined aquifer. There are no groundwater users between the site and the river and reversal (due to pumping) of the groundwater gradient is highly improbable because the site is located on Federally owned and controlled land. The applicant l
has estimated that it would take several hundred years for any postulated i
accidental spill of liquid radwaste at the plant site to travel vertically l
through the 70-35 foot depth to the ground water table.
It would take l
I another 10 -35 years to travel thru the aquifer to the Columbia River.
The staff calculated a groundwater dilution factor of 64 for an accidental liquid radwaste spill, assumed to enter the groundwater aquifer directiv.
l The dilution factor is applicable at the point where the groundwater aquifer i
l l
~
u
. joins the Columbia River east of the site. The travel time for the postu~1ated spill to travel thru the aquifer from the plant to the river was calculated by the staff to be 6 years (does not include vertical travel time from
.radwaste tank to groundwater aquifer).
The groundwater diluted liquid radwaste would be further diluted by a factor of approximately 37,000, assuming complete mixing with the minimum regulated Columbia River flow of 36000 cfs. Refer to section 15.2 for a discussion of radionuclide concentrations.
Groundwater hydrographs over the past 10 years have indicated a rising
_ trend in groundwater icvels. Present groundwater levels are about 10 feet below the foundation level of safety related structures. Hydrostatic pressures, up to elevation 424.5 feet MSL (the probable maximum flood level),
were used in the design of building foundations.
The staff has concluded
_that the applicants design basis for hydrostatic pressures is acceptable.
2.
4.6 CONCLUSION
S We have reviewed the applicant's flood analysis for the plant site, including determination of the maximum river stages on the Columbia River due to PMF, ice, and dam failures and flood conditions at the site and on rooftops due to local intense precipitation of up to PHP severity. We have concluded that the maximum predicted flood levels on the Columbia River are conser'.ative and acceptable. All-safety related structures, except the river intake structure, will be above any reasonably possible Columbia River flood stage. The river intake structure will be designed for river stages up to elevation 373.0 f t MSL, which
,-corresponds to a Columbia River discharge of approximately 400,000 cfs
(
s (compared to the 1948 observed record peak discharge of 690,000 cfs at a st, age of about 375.0 ft MSL). Although the river intake would be subject to flooding by rare floods, and subsequent loss of pump function > the plant can still be brought to a safe shutdown condition and maintair.ed for a period of 30 days through use of the two seismic category I spray ponds.
W We have concluded that _the safety related structures will not be subject to flooding (including flooding of roof penetrations) due to runoff from _a
,, local inte se_ thunderstorm, uhich is the critieni storm for.the plant area.
Ne have found the applicant's analysis of low flowe to be acceptable.
l and although there is a possibility of the occurrence of elver flows less than 36,000 cfs, it is unlikely to happen during the life ef the plant. Even if these flows should occur, they would be for a short duration of time, and the plant.can be brought to a safe shutdown condition through use of the UHS spray ponds, if necessary.
Since the ground water table has.a significent gradient toward the river, is below foundation levels, and there are no groundwater withdrawal between the site and the river, it is concluded that in the event of a postulated accidental liquid radvaste spill, the groundwater will not be a potential pathway to man.
e a
V 4
. ~
l By independent analysis, we have conluded that the spray ponds, will have sufficient water, at a temperature less than the maximum allowable value of 1106, to function as the ultimate heat sink for a 30 day period. However, F
the applicant has stated that design revisions will be necessary to either the equipment or the pond in order to correlate pond return water tempera-tures with equipment design temperatures.
The staff will review new infor-i nation, that is to be submitted by the applicant, and report our findings in a supplement to this report. Resolution of this issue will be required before construction of the spray ponds.
f k __
REFERENCES (1) Artificial Flood Possibilities on the Columbia River, U.S. Army, Corps of Engineers, Seattle District, Seattle, Washington, Nov.1951.
(2) Artificial Flood Considerations for Columbia River Dams, U.S. Army Engir.eer District, Seattle, Corps of Engineers, Seattle, Washington,
August 1963.
(3) Schrock,' V. E., and Trezek, G. J., " Rancho Seco Nuclear Service Spray Ponds Performance Evaluation", University of California, Berkeley.
(4) Generic Emergency Cooling Pond Analysis, U.S. Atomic Energy Commission, May 1972 - October 1972.
~
t e
f I
e p
P P
5 4
4 1
B e
e
- -- +,
- - -