& b i0 -t e s t 2 p au, inc.& b i0 -t e s t 2_p au, inc. 1810 frontage road northbrook,...

& B I0 - T E S T 2_P au, inc. 1810 FRONTAGE ROAD

NORTHBROOK, ILLINOIS 60062

TOXICOLOGY AREA CODE 312

ENVIRONMENTAL SCIENCES TELEPHONE 272-3030

CHEMISTRY

PLANT SCIENCES MEDICAL SCIENCES

REPORT TO

WISCONSIN PUBLIC SERVICE CORPORATION GREEN BAY, WISCONSIN

OPERATIONAL ENVIRONMENTAL MONITORING PROGRAM OF LAKE MICHIGAN NEAR THE

KEWAUNEE NUCLEAR POWER PLANT: PHYSICAL STUDIES

JANUARY-DECEMBER 1974 IBT NO. 643-05086

FOURTH ANNUAL REPORT

PREPARED AND SUBMITTED BY

INDUSTRIAL BIO-TEST LABORATORIES, INC.

Report approved by: <:J /. ' Ji/A. DeMarte, Ph.D. Project Coordinator Environmental Sciences

B. G. J oh son, Ph.D. Manager Environmental Sciences

March 28, 1975

9nda~d-u BIO - TEST aa uel , A.

PREFACE

The three previous annual reports documented the preoperational environ

mental conditions in Lake Michigan near Kewaunee Nuclear Power Plant. The

Fourth Annual Report contains environmental data collected during the first year

of Plant operation. This report consists of two parts: Part 1. Chemical and

Biological Studies; and Part 2. Physical Studies. The Physical Studies are

contained herein and the Chemical and Biological Studies are presented under

a separate cover. Each of these studies has an associated Appendix.

The operational studies reported herein are responsive to the Technical

Specifications for the Kewaunee Nuclear Power Plant, Appendix B - Environ

mental Technical Specifications, as approved by the U. S. Atomic Energy

Commission, as were the 1973 preoperational studies. This provides the

continuity between the period before and after Plant start-up.

i

da~dual BIO - TEST .1aaoue, Ac.

ACKNOWLEDGEMENTS

The Environmental Sciences Division of Industrial BIO-TEST Laboratories,

Inc. acknowledges and appreciates the technical assistance contributed by the

following members of its consulting staff:

Dr. D. A. McCaughran University of Washington Biostatistics

Ms. Mary K. Romeo Private Consultant Programmer/Analyst

The overall coordination of the study program was the responsibility of

Dr. B. G. Johnson, Manager, Environmental Sciences Division, and Dr. J. A.

DeMarte, Project Coordinator. The direction of the Physical Studies was the

responsibility of Mr. F. T. Lovorn, Oceanographer, Physical Sciences Section.

The following BIO-TEST personnel provided technical and supervisory

assistance to the authors of specific chapters in this report:

Mr. D. R. Davidson Physical Sciences

Mr. J. W. Ridgway Physical Sciences

Mr. J. B. Smith Field Operations

Appreciation is expressed to P. Parshall and N. Gara for their cartographic

work, and to M. Leider, E. Wells and E. Tynan for manuscript preparation.

The assistance provided by Mr. Thomas P. Meinz and Mr. Edward N. Newman

of Wisconsin Public Service Corporation during the course of these studies has

also been greatly appreciated.

ii

fa&uial BIO - TEST .1abate,).

PART 1. CHEMICAL AND BIOLOGICAL STUDIES

TABLE OF CONTENTS

Chapter Title

Preface

Acknowledgements

GENERAL INTRODUCTION AND SUMMARY by Joseph A. DeMarte and Larry L. LaJeone

1 THERMAL PLUME SURVEYS by Floyd T. Lovorn

2 WATER CHEMISTRY AND BACTERIOLOGY by David B. Ellis

3 PHYTOPLANKTON by Jose B. Festin

4 ZOOPLANKTON by Janet M. Urry

5 PHYTOPLANKTON ENTRAINMENT by Peter A. Jones, Charles L. Brown, and Darrell G. Redmond

6 ZOOPLANKTON ENTRAINMENT by Daniel L. Wetzel

7 PERIPHYTON by Christopher C. Altstaetter

8 BENTHOS by Joseph H. Rains and Thomas B. Clevenger

9 FISH POPULATION AND LIFE HISTORY by Larry L. LaJeone

iii

/un BIO - TEST .la0eeTE, Sc.

PART 2. PHYSICAL STUDIES

TABLE OF CONTENTS

Chapter Title

Preface

Acknowledgements

GENERAL INTRODUCTION AND SUMMARY

by J. A. DeMarte and F, T. Lovorn

1 SHORELINE EROSION by B. G. Johnson

2 BOTTOM TOPOGRAPHY by W. C. Williams

3 SEDIMENTATION NEAR OUTFALL by W. C. Williams

4 CURRENTS, TEMPERATURE, AND WIND by R. G. Johnson

5 EDDY CIRCULATION by W. C. Williams

6 THERMAL PLUME SURVEYS by F. T. Lovorn

7 THERMAL PLUME MODEL by F. T. Lovorn

iv


Joseph A. DeMarte and Floyd T. Lovorn

OPERATIONAL ENVIRONMENTAL MONITORING PROGRAM OF LAKE MICHIGAN NEAR KEWAUNEE NUCLEAR POWER PLANT:

PHYSICAL STUDIES

FOURTH ANNUAL REPORT January-December 1974

A9daduial BIO0 - T E ST .1anawa A.

Bdad'1 BIO- TEST 2a1k-ied, YAc.


Joseph A. DeMarte and Floyd T. Lovorn

I. Introduction

This report covers the first year of operational environmental monitoring

conducted during 1974, continuing the thermal impact studies to document the

physical conditions of Lake Michigan in the vicinity of the Kewaunee Nuclear

Power Plant near Kewaunee, Wisconsin. These studies are responsive to the

Technical Specifications for the Kewaunee Nuclear Power Plant, Appendix B

Environmental Technical Specifications, as approved by the U. S. Atomic Energy

Commission.

The Kewaunee Nuclear Power Plant (KNPP) is located on the west shore of

Lake Michigan, approximately 8 miles south of Kewaunee, 27 miles southeast of

Green Bay, and 90 miles north of Milwaukee. The facility employs a single

pressurized water reactor (PWR) nuclear generating unit and produces a net

output of 540 megawatts electric (MWe). The unit began operation in June 1974.

Lake Michigan water is circulated in a once-through cooling system which

has a shoreline discharge. The cooling water intake structure is located

approximately 1,600 feet offshore at a depth of 16 feet. Condenser cooling

water is drawn from Lake Michigan at a rate of 287, 000 gallons per minute

(gpm) during winter and 413,000 gpm during summer. The maximum rise in

cooling water temperature is expected to be 28F (15.5C) and 20F (11.1C) above

intake temperature for winter and summer, respectively. Cooling water is dis

charged into an outlet basin at the shoreline through a pipe located just below

1

the lake surface.

The frequency of sampling for each category of the physical studies program

is presented in Table 1. The physical and hydrological studies included such

aspects as water temperature, bottom contours, wind studies, lake current

monitoring, measurement of the extent and shape of the thermal plume, numerical

predictive thermal plume model, and documentation of shoreline erosion near

KNPP. Four of the thermal plume surveys were conducted concurrently with

the biological and water quality sampling.

The results of the 1974 Physical Studies are reported under technical titles

in individual chapters of this report. The specific objectives of each individual

study are covered in detail in the respective chapters, together with a presenta

tion of results and conclusions. All numerical data collected or developed are

presented in the Appendix for Part 2. Physical Studies.

2

A~dade BIO0 - T E ST JAaAal wA.

0

Table 1. Timetable for various categories of the physical Power Plant, 1974.

studies program for the Kewaunee Nuclear

1974 Period of Study

Study Category Mar Apr May Jun Jul Aug Sep Oct Nov Dec

A. Bathymetry X X

B. Eddy Circulation X X X X

C. Continuous Current, Temperature and Wind Studies X X X X X X

D.1 Dye Survey for Model Verification x

D.2 Monthly Plume Survey for Biological Support X X xa Xa X X

E. Comparative Analysis Between Model and (Laboratory analyses - following Field Survey Data August studies)

F. Shoreline Erosion X X X X

a Plant was not operating, only ambient temperatures measured.

0

m m

edadtial BIO - TEST .A6wadowi , nc.

II. Summary

The data collected as part of these 1974 studies, together with those from

the three previous programs in 1971, 1972, and 1973, provide a detailed

description of preoperational and operational conditions in the vicinity of the

Kewaunee Nuclear Power Plant.

The following statements provide a summary of the general objectives of

the 1974 Physical Studies:

1. to evaluate shoreline erosion in the vicinity of the Plant;

2. to provide a detailed bathymetric survey of the lake near the Plant

and to evaluate the effect of the Plant's discharge upon the bottom contours;

3. to provide a study of the possible existence of eddy currents in the

vicinity of the promontory south of the Plant;

4. to monitor lake current, temperature, and wind during plant operation;

5. to monitor the thermal plume for verification of the predictive model

and in support of biological monitoring; and

6. to provide a comparative analysis between the predictive thermal plume

model and the data obtained in plume surveys.

The summary and conclusions from each of the 1974 Physical Studies reported

under individual technical titles in chapters of this report follow:

Chapter 1. Shoreline Erosion

1. The shoreiine in the vicinit of the KNPP has been subjected to severe

erosion and much of it continues in an unstabilized. state.

2. The shoreline to the north and south of the KNPP site continues to be

4

Adad2ial BIO - TEST .aA4 aoie,c.'w

generally characterized by a narrow beach backed by steep, unstabilized soil

banks ranging from 10 to 60 feet in height.

3. The shoreline at the KNPP continues to be generally characterized by a

narrow beach and gradual rise in elevation back away from the shore, with the

shoreline in the immediate vicinity stabilized by rip-rap.

4. No seasonal variation was apparent in the relative degree of erosion

occurring during 1974; variations in water levels were noted.

5. No significant change in shoreline configuration was noted in 1974.

6. No unusual or unexpected erosion was noted that could be attributed to

the operation of the KNPP.

Chapter 2. Bottom Topography

1. The bottom topography near KNPP is very irregular with numerous

ridges and troughs between the 20 ft and 50 ft isobaths.

2. The promontory is a major bathymetric feature which extends approxi

mately 2500 ft offshore to the 30 ft contour and has an approximate width of

1500 ft.

3. A 6 ft high ridge extends 2 miles north-south at a distance of approxi

mately 1.25 miles offshore.

4. A detailed bathymetric chart has been prepared which delineates the

bottom topography in the immediate vicinity of KNPP.

Chapter 3. Sedimentation Near Outfall

1. The discharge from KNPP is altering the lake bottom within a small area

250 ft wide and extending 400 ft offshore.

5

BA0a - T ET0-TEST .aaeu, APzc.

2. The lake bottom is being scoured within 50 ft to 100 ft from the dis

charge outlet.

3. Sediment transported offshore by the discharge is apparently being

deposited within 150 ft to 300 ft from the discharge outlet.

Chapter 4. Nearshore Currents, Temperature, and Wind

1. The data collected describe the spatial and temporal nearshore circula

tion and temperature structure and the wind distribution in the vicinity of KNPP

for the June-December 1974 measurement period.

2. The data collected were sufficiently representative to provide useful

input into the KNPP thermal plume model.

3. The water mass movement in the area of KNPP is spatially homogeneous

in speed. The direction of flow is influenced by the bottom topography and the

prevailing local winds.

4. The promontory in the region of the condenser cooling water intake

plays a major role in the general water circulation in the vicinity of the KNPP.

5. The net displacement of water past the KNPP was generally shore-parallel

toward the northeast at a typical mean speed of 0.054 ft/sec. Average monthly

current speeds range between 0.17 ft/sec and 0.28 ft/sec. The maximum current

speed recorded was 1.2 ft/sec.

6. The greatest persistence of current in a single direction was 42 hours

toward the NNW and the greatest persistence of current speed was 55 hours for

speeds within the 0.1-0.24 ft/sec class.

7. Periods of greatest temperature range occurred during July. This range

6

ndadAwal BIO - TEST ./ana&ume, Inc.

was found to be as great as 13.7 C.

8. A maximum temperature of 21.7 C was recorded during July at the Off

shore Surface Mooring location and a minimum temperature of 0.2 C was recorded

during December at the South-Mooring location.

9. Monthly mean temperatures at all locations differed by 0.5 C or less.

10. Net wind displacement past the KNPP was generally toward the northeast

at a typical speed of displacement of 6.4 ft/sec. Average monthly wind speeds

ranged from 13-20 ft/sec. The maximum wind speed recorded was 54 ft/sec.

11. The greatest persistence of wind in a single direction was 18 hours

toward ESE and the greatest persistence of wind speed was 24 hours for speeds

>35 ft/sec.

Chapter 5. Eddy Circulation

1. An eddy circulation north of the promontory was associated with north

ward currents and affected an area of approximately 104 acres.

2. Southward currents were deflected to the southeast by the promontory.

There was no evidence of an eddy circulation associated with a southward

current.

3. Temperature measurements were not successful in defining an eddy

circulation pattern.

Chapter 6. Thermal Plume Surveys

1 -- . surveyedLi cocretyjith biologialn

chemical sampling in the same area.

2. An intensive study of eleven plumes was successfully conducted using

7

Adadmial BIO - TEST Jatca , A.

dye tracer techniques.

3. Characteristics of each plume such as centerline distance, maximum

width, surface area, and half-depth were measured and tabulated. These data

will provide input and comparisons for the KNPP thermal plume model.

4. Mixing with ambient water was the dominant factor in reducing the

size of the thermal plume when AT/ATo was greater than 0.1 and the Plant was

operating near 50% power.

5. Direct heat transfer to the atmosphere did not make a measurable

contribution to reducing the size of the thermal plume when AT/ATo was greater

than 0.1 and the Plant was operating near 50% power.

6. The mean half-depth of the plumes measured in November was 3.5 meters.

7. Time-temperature profiles indicated that an organism present in the dis

charge from the Plant would experience a 50% decrease in excess temperature

within 15 minutes and 1200 ft from the discharge outlet.

8. The discharge velocity decreased by 50% within 150 ft of the discharge

outlet.

Chapter 7. Thermal Plume Model

1. Predictions of the half-depth of the plume are too large by a factor of

two.

2. The centerline distance for those excess temperatures greater than 20%

of the initial excess temperature can be predicted within a factor of two.

3. The maximum width for those excess temperatures greater than 20% of

the initial excess temperature can be predicted within a factor of 1.7.

8

Andad al BIO - TEST 2a/Z-abw, 9nc.

4. The area for those excess temperatures greater than 20% of the initial

excess temperature can be predicted within a factor of three.

5. The model underestimates the amount of mixing when the excess tempera

ture is less than 20% of the initial excess temperature and therefore overestimates

the size of the plume at these temperatures.

9

dadd 1 BIO- TEST JaA4awie&, Inc.

Chapter 1

SHORELINE EROSION

B. G. Johnson


PHYSICAL STUDIES


9"ahdal BIO - TEST 2amal4ie, Ac.

TABLE OF CONTENTS

List of Figures

List of Tables . . . ......

Introduction . . .......

Field and Analytical Procedures

Results and Discussion . ....

Summary and Conclusions . . . .

References Cited . . . . . . .

i

I.

II.

I V.

V.

Page

.. . 11

.. . 111

. . . .. . . . . . 1

. . . . . . ... . . . . 2

. 4

. . 15

* * 16

~dadual BIO - TEST Jaknateww, Inc.

LIST OF FIGURES

No. Caption Page

1. 1 Shoreline approximately 1 mi north of the KNPP showing steep, unstabilized soil banks, 1974......... . . . . . . 5

1. 2 Seasonal erosion and deposition at mouth of creek located 3/4 mi north of the KNPP, 1974............. . . . . 6

1. 3 Shoreline and lake levels at the KNPP in the immediate vicinity of the discharge, 1974. . . . . . . . . . . . . . . . . . 7

1.4 Shoreline approximately 1 mi south of the KNPP, 1974 . . . . . 8

1. 5 Higher altitude photographs showing general shoreline configuration in the vicinity of the KNPP, 1974....... . . . . . 9

ii

%tAda1al BIO-TEST .0ao -ie, TAcS.

LIST OF TABLES

Caption

Lake Michigan water levels during 1974...... . . . . .

Meteorological conditions in the vicinity of the KNPP at the time of aerial photography, 1974....... . . . . ..

111

No.

1. 1

1.2

Page

11

12

Chapter 1

SHORELINE EROSION

B. G. Johnson

I. Introduction

Shoreline erosion was one of the physical conditions to be documented and

described in the vicinity of the Kewaunee Nuclear Power Plant (KNPP) as

indicated in the Environmental Technical Specifications, Appendix B. The

documentation was accomplished by means of aerial photographs taken during

1974, the first year of Plant operation and the fourth year of environmental

monitoring studies.

The primary objectives for conducting this program in 1974 were:

1. To determine the present state of shoreline erosion;

2. To describe the seasonal variation in the relative degree of

erosion occurring;

3. To begin documentation of operational conditions relative to erosion

in the vicinity of the KNPP for comparison with data collected during the pre

operational period; and

4. To fulfill the requirements of the Environmental Technical

Specifications, Appendix B. Section 4. 0 Environmental Surveillance and Special

Studies, as approved by the U. S. Atomic Energy Commission.

YnaAdul BIO0 - T ES T Advatones, Acw.

Ad)ad BIO - TEST Jaleate, A~c.

II. Field and Analytical Procedures

Aerial photographs of the shoreline in the vicinity of the KNPP were taken

quarterly during 1974, from a point approximately 2 1/4 miles north of the

Plant to a point approximately 2 1/2 miles south of the Plant to determine the

extent of shoreline erosion or deposition. The quarterly photographic dates

were April 11, June 28, September 24 and December 26, 1974. The first

quarter photographs were those retaken on April 11 due to a camera malfunction

on March 26 which resulted in poor film exposure.

Photographs were taken from a Cessna 172 Skyhawk rented from Green

Bay Aviation, Austin Straubel Field, Green Bay. This high-wing aircraft was

an excellent vehicle from which to take low altitude photographs because of its

window configuration and maneuverability. During each photographic trip,

photographs were taken from at least three altitudes and while flying either

parallel to the shoreline or perpendicular to it. Altitudes were usually at

150-200 ft and at 250-300 ft while flying parallel to the shoreline and just

offshore. This permitted close-up photos and observations to be made of the

beach and bluff zones. Photographs were keyed to the same topographic features

or landmarks during each quarter for comparative purposes. Photos. taken per

pendicular to the shoreline were taken from an altitude of 250-300 ft while crossing

back and forth over the shoreline permitting photos and observations to be made

up and down the shoreline. Higher altitude photographs, from approximately

1000 ft, were taken of the KNPP and immediate shoreline both north and south

of the Plant.

2

f)adala BIO - TEST 2a4alwe49, In.

In 1974, aerial photographs were taken on a quarterly basis for the first

time during the operational period, although aerial photographs of the shore

line had been taken previously during the preoperational period in 1971, 1972

and 1973 (Industrial BIO-TEST Laboratories, Inc. 1972, 1973, 1974).

Records of water levels in Lake Michigan were obtained from the U. S.

Department of Commerce (Department of Commerce 1975a, 1975b, 1975c). Water

levels served as a basis for making seasonal comparisons. Meteorological

conditions existing at the time aerial photographs were taken were obtained from

the data record from the ongoing meteorological monitoring program being

conducted at the KNPP site.

3

Ada~d-i'1 BIO- TEST ./a4mat4a, c.

III. Results and Discussion

The Lake Michigan shoreline in the vicinity of the Kewaunee Nuclear Power

Plant is characterized by a narrow beach composed of beach sand and gravel,

which grades to gravel and rubble out from shore (Poff and Threinen 1966),

backed by steep, unstabilized soil banks or bluffs ranging from 10 to 60 ft in

height. Grass and tree cover on the bluffs is uncommon except in areas north

of the Plant. Trees are common in ravines associated with the small tributaries

entering Lake Michigan within the study area and this accounts for a number of

fallen trees along the shoreline.

These facts are confirmed by the photographic record that was made during

1974 which also documents the present state of erosion in the vicinity of the

KNPP. Some typical photographs in seasonal series are presented in Figures

1. 1, 1. 2, 1. 3 and 1. 4 showing typical shoreline conditions. In addition,

higher altitude photographs of the immediate KNPP shoreline area permitted

an overview of the general area near the Plant (Figure 1. 5).

Seasonal changes due to erosion and deposition were most noticeable at the

mouths of the small creeks flowing into Lake Michigan within the area being

observed. The changing pattern of the outfall configuration reflects the dynamic

nature of the lake's effect on the shoreline (Figure 1. 2). Some sediment deposition

was observed in the area immediately adjacent to and south of the KNPP dis

charge structure during the fourth quarter, December 26 (Figure 1. 3). This

appears to be a new sediment deposit of sand not observed earlier. Observations

in the ongoing program will help in determining whether or not it has only

4

U...

S -

Figure 1. 1. Shoreline approximately 1 mi north of the KNPP showing steep, unstabilized soil banks, 1974. (Upper left, April 11; upper right, June 28; lower left, September 24; lower right, December 26.)

Figure 1. 2. Seasonal erosion and deposition at mouth of creek located 3/4 mi north of the KNPP, 1974. (Upper left, April 11; upper right, June 28; lower left, September 24; lower

right, December 26. )

0

.......

I

7L 7f

Figure 1. 3. Shoreline and lake levels at the KNPP in the immediate vicinity of the discharge, 1974. (Upper left, April 11; upper right, June 28; lower left, September 24; lower right, December 26.)

Figure 1. 4. Shoreline approximately 1 mi south of the KNPP, 1974. (Upper left, April 11; upper

right, June 28; lower left, September 24; lower right, December 28.)

J"

0 0

A

~

Figure 1. 5. Higher altitude photographs showing general shoreline configuration in the vicinity of the KNPP, 1974. (Upper photo, June 28; lower left, September 24; lower right, December 26.)

A dad4l BIO - TEST Ja/sowaIac.

become more apparent due to the lower water levels, or has resulted from lateral

transport and deposition at that location due to current action, or is a transient

deposit due to changing wave action.

The shoreline in the vicinity of the KNPP continues to show evidence of

past severe erosion, principally due to continued high water levels in Lake

Michigan. Shore erosion is related to lake levels in Lake Michigan, and a

significant correlationhas been noted between the average rate of erosion and

the average lake levels for periods of measurement (Seibel 1974). Lake Michigan

water levels during 1974, for the periods when aerial photographs and observa

tions were made, are shown in Table 1. 1. The Milwaukee and Sturgeon Bay

Canal locations permit an accurate estimate of lake levels in the vicinity of the

KNPP as these are the closest official lake gauging stations both north and south

of the Plant. Highest water levels were reached in late June and early July.

Seasonal differences in beach exposure and lake levels are apparent from photo

graphs taken in the vicinity of the KNPP (Figures 1. 1 and 1. 4). Earlier in 1974,

lake levels were similar to those observed during the same period in 1973. Pro

jections are that lake levels will be at their lowest in more than 2 years during

the winter months of 1974-75 (Department of Commerce 1975a).

Meteorological conditions during 1974, for the periods when aerial photo

graphs and observations were made, are shown in Table 1. 2. These data are

provided to assist further in understanding the various factors affecting wave

action and apparent water levels. For example, on September 24 with the

surface winds relatively strong and steady out of the south (15 to 20 mph), the

10

I

Table 1. 1. Lake Michigan water levels during 19 7 4 .a

Photographic Daily Daily Date and Location Daily Mean Monthly Mean Maximum Minimum

April 11 Milwaukeeb 580. 51 580.49 581. 22 579.95 Sturgeon Bayc 580. 36 580. 39 580.90 579. 91

June 28 Milwaukee 581. 19 581.07 582.08 580. 35 Sturgeon Bay 581. 12 581.00 581.47 580. 58

September 24 Milwaukee 580. 12 580. 51 580.97 579.87

Sturgeon Bay 580. 16 580.46 581.00 579. 90

December 26 Milwaukee 579. 39 579.84 580.77 579.03 Sturgeon Bay 579. 50 579. 78 580. 58 579. 19

a Elevations are in feet above mean water level in Gulf of St. Lawrence at Father Point, Quebec.

b Based on levels determined at Milwaukee, Wisconsin, Station Number 7057 (Department of Commerce 1975b).

c Based on levels determined at Sturgeon Bay Canal, Wisconsin, Station Number 7072 (Department of Commerce 1975c).

0 as rO **4

A)zdadt~ial BIO - TEST .aake,,c.

Table 1. 2. Meteorological conditions in the aerial photography, 1974. a

vicinity of the KNPP at the time of

Wind Speed Temperature

Date Direction (mph) (- F) Cloud Cover

April 11 SE 6 to 10 37.5 Overcast

June 28 S 8 to 12 64.0 Clear

September 24 S 15 to 20 54.5 Overcast

December 26 S 12 to 15 25. 0 Scattered clouds

a Data from meteorological program being conducted at the KNPP; collected at the on-site meteorological tower, 35-ft level.

12

S)dedud4 BIO -TEST a~oaloes, .

water level appeared to be higher than that actually recorded (Table 1. 1) due to

the higher waves and greater wave run-up on the beaches.

The shoreline in the vicinity of the KNPP has been subjected to severe

erosion during the past several years. The combination of rising lake level and

storm activity facilitate erosion and provide a seasonal pattern. Davis et al.

(1974) report that the most extensive losses are in the fall, and a less damaging

period of erosion occurs after ice breaks up in the spring. During 1973, obser

vations indicated that the period of most extensive erosion occurred in the spring

between March and June. The absence of severe spring storms in 1974 resulted

in considerably less change in shoreline configuration during the first 6 months

of 1974 than during the same period in 1973, although daily mean water levels

were very similar. During the second six months of 1974 water levels appeared

to be declining with more beach exposure noted. There were no new changes

observed in shoreline configuration indicating at least a temporary cessation

of the active erosion observed in 1973 and earlier. Also, this slowing of erosion

may have resulted from the absence of severe storms in 1974.

On 28 June 1974, aerial observations of the nearshore lake bottom were

possible due to the unusual clarity and low turbidity of the nearshore waters in

the vicinity of the KNPP discharge. A darker "shadow'', possibly periphytic

growth, was noted along the bottom on both the shallower parts of the promontory

just south of the KNPP and along a line directly offshore from the plant discharge

(Figures 1. 3 and 1. 5). This information was transmitted to the Aquatic Ecology

Periphyton staff who have followed up in identifying the source. This is reported

13

Bd d 10a BIO- TEST .a4a4ie, c.

in Chapter 7, Operational Environmental Monitoring Program of Lake Michigan

near Kewaunee Nuclear Power Plant: Chemical and Biological Studies, Fourth

Annual Report, January-December 1974 (Part I).

14

ndadual BIO - TEST Ya al1e, Ac.

IV. Summary and Conclusions

1. The shoreline in the vicinity of the KNPP has been subjected to severe

erosion and much of it continues in an unstabilized state.

2. The shoreline to the north and south of the KNPP site continues to be

generally characterized by a narrow beach backed by steep, unstablized soil

banks ranging from 10 to 60 feet in height.

3. The shoreline at the KNPP continues to be generally characterized by

a narrow beach and gradual rise in elevation back away from the shore, with the

shoreline in the immediate vicinity stabilized by rip-rap.

4. No seasonal variation was apparent in the relative degree of erosion

occurring during 1974; variations in water levels were noted.

5. No significant change in shoreline configuration was noted in 1974.

6. No unusual or unexpected erosion was noted that could be attributed to

the operation of the KNPP.

15

ndadual BIO - TE S T 2a6o-a4iu, Ac.

V. References Cited

Davis, Richard A., Erwin Seibel, and Wm. T. Fox. 1974. Coastal erosion in the Great Lakes - causes and effects. Proc. 16th Conf. Great Lakes Res., Internat. Assoc. Great Lakes Research.

Department of Commerce. 1975a. Monthly bulletin of lake levels for December 1974, Lake Michigan - Huron. NOAA - National Ocean Survey, Lake Survey Center, Detroit, Michigan.

. 1975b. 1974 Daily mean water levels; Milwaukee, Wisconsin

on Lake Michigan (Station Number 7057). NOAA - National Ocean Survey, Lake Survey Center, Detroit, Michigan.

. 1975c. 1974 Daily mean water levels; Sturgeon Bay Canal, Wisconsin on Lake Michigan (Station Number 7072). NOAA - National Ocean Survey, Lake Survey Center, Detroit, Michigan.

Industrial BIO-TEST Laboratories, Inc. 1972. Preoperational thermal monitoring program of Lake Michigan near Kewaunee Nuclear Power Plant, January-December 1971. (IBT No. W9438). Report to Wisconsin Public Service Corporation, Green Bay, Wisconsin. 191 p.

. 1973. Preoperational thermal monitoring program of Lake Michigan near Kewaunee Nuclear Power Plant, Second Annual Report, January-December 1972. (IBT No. W1808). Report to Wisconsin Public Service Corporation, Green Bay, Wisconsin. 561 p.

1974. Preoperational thermal monitoring program of Lake

Michigan near Kewaunee Nuclear Power Plant, Third Annual Report, January-December 1973. (IBT No. 64303208). Report to Wisconsin Public Service Corporation, Green Bay, Wisconsin. 495 p.

Poff, Ronald and C. W. Threinen. 1966. Surface water resources of Kewaunee County. Lake and stream classification project. Wisconsin Conservation Department, Madison. 51 p.

Seibel, Erwin. 1974. Shore erosion in relation to lake level in Lakes Michigan and Huron. Proc. 16th Conf. Great Lakes Res. , Internat. Assoc. Great Lakes Research.

16

Andadi-l BIO - TEST 2aAnalwesi, YIc.

Chapter 2

BOTTOM TOPOGRAPHY

William C. Williams

OPERATIONAL ENVIRONMENTAL MONITORING PROGRAM

OF LAKE MICHIGAN NEAR KEWAUNEE NUCLEAR POWER PLANT: PHYSICAL STUDIES

FOURTH ANNUAL REPORT January - December 1974

A"dad,4al BIO - TE S T .a/awawel, c.

TABLE OF CONTENTS

No.Page

List of Figures ........................................... n....ii

I. Introduction ...................................................... 1

II. Field and Analytical Procedures ................................ 2

III. Results and Discussion .......................................... 3

IV. Summary and Conclusion ....... ................................ 6

V. References Cited ............................................... 7

i

A dad2ial BIO - TEST J2almateu, Inc.

LIST OF FIGURES

Caption

2.1 Bottom topography in the vicinity of the Kewaunee Nuclear Power Plant, 29 May 1974 .............................

Page

4

ii

No.

dia~ l1 BIO- TEST Jaiela,9Ic.

Chapter 2

BOTTOM TOPOGRAPHY

William C. Williams

I. Introduction

A bathymetric survey of Lake Michigan in the vicinity of the Kewaunee

Nuclear Power Plant (KNPP) was conducted in 1974. The objectives of this

survey were:

1. to provide a detailed bathymetric survey of the bottom topography near

KNPP; and

2. to prepare a depth contour map for use as a basis for other studies

conducted in Lake Michigan in the vicinity of the Plant.

1


On 29 May 1974, Industrial BIO-TEST Laboratories, Inc. conducted a bathy

metric survey of the bottom topography offshore of KNPP. A boat equipped with

navigation and depth finding equipment was used to survey the lake bottom along

twenty transects between the shoreline and the 50 ft depth contour. Transects

perpendicular to the shoreline were made at approximately 1000 ft intervals from

1.25 miles north of the Plant to about 2 miles south of the Plant. A Raytheon

Model DE-719B, continuous recording fathometer, was used to measure and record

water depth. Depth was recorded by the fathometer on chart paper with an

accuracy of 0.5% + 1 inch of the indicated depth at a rate of 534 soundings

per minute. The boat's location was determined with a Mortorla Mini-Ranger

Navigation System, Model 1 (MRS-1), which has as accuracy greater than + 10 ft.

at a range up to 20 nautical miles. Data from the navigation system and local

time from a digital clock (NES Model DC1205) were recorded by an on-board

digital printer (Anadex Model DP650A) at approximately one second intervals.

A time mark which enabled an accurate correlation of depth and location was

periodically recorded on the fathometer chart paper.

With the aid of a digital computer and a Calcomp-plotter, the depths and

boat position along each transect were accurately plotted. From these plots,

isobaths (lines of constant depth) were contoured at 2 ft intervals.

2

Adu-wa BIO - T E ST 264akaves, Ac&.

III. Results and discussion

A chart of the bottom topography near KNPP is presented in Figure 2.1.

In general, the lake bottom near the Plant is irregular with numerous ridges

and troughs extending north and south. The slope of the bottom is 1 in 100

from the shoreline to the 20 ft contour, and a slope of 1 in 300 from the 20

ft contour to the 40 ft contour. The average alignment of the isobaths is

southwest to northeast but in the nearshore zone, the alignment of the

isobaths is influenced by the promontory.

The study area has two major topographic features. The most prominent

feature is the promontory which extends approximately 2500 ft into the water

and has a width of approximately 1500 ft. The end of the promontory is

marked by a steep slope between the 20 ft and 30 ft isobath. It has been

determined, (Pezzetta, 1974) that this section of the near shore zone is an

extension of the promontory on which the Plant is located and is made up of

a hard glaciolacustrine clay or an exposed area of dolomitic bedrock covered

with numerous cobbles which were transported from the clay bluffs along

shore.

The other prominent feature of the topography is a ridge which is

located approximately 1.25 miles offshore. The ridge rises 6 ft off the

bottom and extends north-south for 2 miles along the 36 ft isobath. The

irregularity in the bathymetry, reported in a previous survey (Industrial BIO

TEST Laboratories, Inc., 1973) was probably due to this ridge and numerous

other ridges and troughs which are found to extend north-south between the

3

~da:dua BIO0 - T E ST .Ana9u,=A.

9feded-d BIO - TEST .aA abte , Ac.

4

Figure 2. 1 Bottom topography of Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant, 29 May 1974. Depths are in feet. The daily mean water level was 580.79 ft above mean sea level.

B d10aa BIO- TE S T Jaaw&a, YAc.

20 and 50 ft isobaths. Because of their height and shape, it is believed that

some of the ridges are sand bars formed by wave action.

5

IV. Summary and Conclusion

1. The bottom topography near KNPP is very irregular with numerous

ridges and troughs between the 20 ft and 50 ft isobaths.

2. The promontory is a major bathymetric feature which extends approxi

mately 2500 ft offshore to the 30 ft contour and has an approximate width of

1500 ft.

3. A 6 ft high ridge extends 2 miles north-south at a distance of approxi

mately 1.25 miles offshore.

4. A detailed bathymetric chart has been prepared which delineates the

bottom topography in the immediate vicinity of KNPP.

6

Yaa, BIO0 - T E S T la"4atoue, Inc.

V. References Cited

Industrial BIO-TEST Laboratories, Inc. 1973. Preoperationdl thermal monitoring program of Lake Michigan near Kewaunee Nuclear Power Plant, JanuaryDecember 1973 (IBT No. 643-03208). Report to Wisconsin Public Service Corporation, Green Bay, Wisconsin. 1275 p.

Pezzetta, J. M. 1974. Sedimentation off the Kewaunee Nuclear Power Plant. Sea Grant College Technical Report (WIS-SG-74-221), University of Wisconsin, Green Bay, Wisconsin. 59 p.

7

Adedwald BIO0 - T E ST _Zalaw , Ac.

ndda za BIO - TEST JaYiel Ic.

Chapter 3

SEDIMENTATION NEAR OUTFALL

William C. Williams


PHYSICAL STUDIES

FO URTH AMNTTTA T REPORT January - December 1974

Snded"2ial BIO - TEST Ja4 a&,ue&, A9c.

TABLE OF CONTENTS

List of Figures ....................

List of Tables .....................

Introduction .......................

Field and Analytical Procedures ....

Results and Discussion .............

Summary and Conclusion ...........

References Cited

i

I.

II.

III.

V.

Page

ii

1

2

7

15

16

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. .. . . . . . . .

. . ... . . . . .

. ... . . . . . .

. .. . . . . . .

. . .. . . . . . .

. .. . . . . . .

S. . . . . . . .

AddiaLd BIO - TEST .- a9a"iawIc.

LIST OF FIGURES

No. Caption Page

3.1 Transects used for the bathymetric survey in the vicinity of the discharge outlet at Kewaunee Nuclear Power Plant on Lake Michigan, 28 August 1974 ............................ 3

3.2 Transects used for the bathymetric survey in the vicinity of the discharge outlet at Kewaunee Nuclear Power Plant on Lake Michigan, 12 November 1974 ........................ 4

3.3 Sampling locations for bottom sediments of Lake Michigan

in the vicinity of the discharge outlet at Kewaunee Nuclear Power Plant ........................................ 6

3.4 Bottom topography in the vicinity of the discharge outlet

at Kewaunee Nuclear Power Plant on Lake Michigan,

28 August 1974 .............................................. 8

3.5 Bottom topography in the vicinity of the discharge

outlet at Kewaunee Nuclear Power Plant on Lake

Michigan, 12 November 1974 ................................ 9

3.6 Size distribution of bottom sediments in the vicinity

of the discharge outlet at Kewaunee Nuclear Power

Plant on Lake Michigan, 28 August 1974 ..................... 11

3.7 Size distribution of bottom sediments in the vicinity of the discharge outlet at Kewaunee Nuclear Power

Plant on Lake Michigan, 12 November 1974 .................. 12

ii

Andaduial BIO0 - T E S T.antuc

LIST OF TABLES

No. Caption Page

1 Percent composition of sediment types and general description of sediment samples collected in Lake Michigan near the

discharge outlet of the Kewaunee Nuclear Power Plant,

28 A ugust 1974 ................................................... 13

2 Percent composition of sediment types and general description

of sediment samples collected in Lake Michigan near the

discharge outlet of the Kewaunee Nuclear Power Plant,

12 November 1974 ..................................................... 14

iii

~dud 1 BIO- TEST a w c.

Chapter 3

SEDIMENTATION NEAR OUTFALL

William C. Williams

I. Introduction

During 1974, bottom sediment and bathymetric surveys were conducted

in Lake Michigan near the discharge outlet of the Kewaunee Nuclear Power

Plant (KNPP). The objectives of these surveys were:

1. to evaluate the effect of the KNPP cooling water discharge upon the

sediment distribution and bottom topography near the KNPP discharge outlet;

and

2. to provide detailed charts of the bottom topography in the immediate

vicinity of the KNPP discharge outlet.

1

I


On 28 August and 12 November 1974, a boat equipped with navigation

and depth finding systems was used to conduct detailed bathymetric surveys

of the bottom topography in the immediate vicinity of the KNPP discharge out

let. The boat traversed several transects parallel to the shoreline in front of

the discharge outlet (Figure 3.1 and 3.2). A Raytheon (Model DE-719B) con

tinuous recording fathometer was used to measure and record water depth.

Depth was recorded by the fathometer on chart paper with an accuracy of

0.5% + 1 inch of the indicated depth at a rate of 534 soundings per minute.

The boat's location was determined with a Mortorla Mini-Ranger Navigation

System, Model 1 (MRS-1), which has a accuracy of better than + 10 ft at

a range up to 20 nautical miles. Data from the navigation system and real

time from a digital clock (NES Model DC 1205) were recorded by an on-board

digital printer (Anadex) at approximately one second intervals. A time mark

which enabled an accurate correlation of depth and location was periodically

recorded on the fathometer chart paper.

In order to compare the two surveys, an adjustment for the change in

lake level between August and November was required. It was arbitrarily

chosen to correct the November data to the Lake level on 28 August 1974.

Water level data was obtained from Station Number 7072 at the Coast Guard

Channel Station Sturgeon Bay, Wisconsin and is presented below (Dept. of

Commerce, 1974).

2

Bdda BIO - T E ST .alm , Acw.

Figure 3.1.

0

m

Transects used for the bathymetric survey in the vicinity of the discharge outlet at

Kewaunee Nuclear Power Plant on Lake Michigan, 28 August 1974.

FENCE #2 # I0

ADMIN. #9 AREA #7 #5 # 3

DISCHARGE SCREENHOUSE #I0

#8

#6 #4

GUARD HOUSE

KEWAUNEE NUCLEAR POWER PLANT

SCALE IN METERS OBSERVATION

0 10 20 30 40 50 75 100 BOOTH

SCALE IN FEET OO

0 50 100 200 300

PARKING

Figure 3.2. Transects used for the bathymetric survey in the vicinity of the discharge outlet at

Kewaunee Nuclear Power Plant on Lake Michigan, 12 November 1974.

9ndia~1 BIO- TEST 2a4aw&a, c.

Daily Mean Water Levels International Great Lakes Datum (IGLD) 1955

Station Number 7072

Date Water Level

28 August 1974 580.77 12 Nov 1974 579.91

With the aid of a digital computer and a Calcomp-plotter, the location and

corrected depths were accurately plotted. From these plots, isobaths (lines

of constant depth) were contoured at 1 ft intervals.

After each bathymetric survey was completed, duplicate samples of

bottom sediment were collected at five stations near the Plant's discharge

outlet (Figure 3. 3). A diver was used to collect the samples and visually

describe the sediment and bottom topography.

The samples of bottom sediment were dried and analyzed for particle

size to give percent composition by weight in 6 classes using procedures

set forward in American Society for Testing and Materials (ASTM 1973).

The six classes are:

Sediment Type Size Class (mm)

Clay < 0.004

Silt 0.004 - 0.063

Fine sand 0.063 - 0.500

Medium sand 0.500 - 2.000

Coarse sand 2.000 - 4.000

Gravel > 4-000

The general sediment types were qualitatively described using the categories

of Shepard and Moore (1955). Plots were made showing the composition and

sediment distribution in relation to the discharge.

5

I

(,-

Figure 3.3

O

0

-I

Sampling locations for bottom sediments of Lake Michigan in the vicinity of the

discharge outlet at Kewaunee Nuclear Power Plant.

Addial BIO - TEST .&Ae4taw, c.


Charts of the bottom topography in the immediate vicinity of the KNPP

discharge outlet are presented in Figures 3.4 and 3.5, for the 28 August and

12 November surveys, respectively. The two charts are not strictly comparable,

however, since the patterns of survey transects (Figures 3.1 and 3.2) were

not identical. Thus, differences in the bottom topography between the two sur

veys may be a result of the different survey patterns rather than actual bottom

changes. . Nevertheless, both charts reveal consistent features which indicate

an apparent influence of the Plant's 412000 gpm cooling water discharge on the

bottom topography.

A small ridge defined by the 7 ft contour just north of the discharge outlet

is common to the charts of both surveys. This feature indicates a possible

diversion of the alongshore transport of sediment. That is, sediment moving

southward could be carried offshore by the high volume discharge from the

Plant and deposited where the current velocity drops below that needed to

transport the sediment.

The 12 November survey provided significant evidence for the effect of

the Plant's discharge on the bottom topography. This survey revealed a

depression immediately in front of the discharge outlet. It also revealed a

small mound just offshore of the depression and defined by a 7 ft contour.

It is believed that the depression was created by scouring and the mound was

built by depositing sediment from both scouring and diversion of alongshore

sediment transport. This is supported by evidence from the distribution

7

L AK E M /CH/ GA N

10 INI

9 13

12

8 7

FENCE

AMIN.0 EA

10 I

.5 9 DISCH ARGE

HOUSE

6 7 66

GUARD HOUSE 6


9 10

SCALE IN METERS OBSERVATION 9 010 20 304050 75 100

SCALE IN FEET

0 50 100 200 300

PARKING

Figure 3.4. Bottom topography in the vicinity of the discharge outlet at Kewaunee Nuclear Power

Plant on Lake Michigan, 28 August 1974.

Figure 3.5.

0

-4

Bottom topography in the vicinity of the discharge outlet at Kewaunee Nuclear Power Plant on Lake Michigan, 12 November 1974.

Bndd 0 BIO- TEST _9"c.

of bottom sediments discussed below.

The size distribution of bottom sediments collected in the immediate

area of the discharge outlet on 28 August and 12 November are presented

in Figures 3.6 and 3.7, respectively. The percent composition of sediment

types and general description of sediment samples are represented in Tables

3.1 and 3.2. In both cases, the size of the sediments graded from gravel

immediately in front of the discharge outlet to fine sand on either side and

offshore. This sorting by size was a result of selective erosion and deposi

tion of sediment and is associated with changes in current velocity. The

sand fraction was scoured from the area immediately in front of the discharge

outlet and transported offshore to a point where the current velocity dropped

below that needed to transport the sand. A comparison of the sediment distri

bution and bottom topography on 12 November reveals that the depression was

an area with a large fraction of gravel; whereas, the mound was an area with

a large fraction of fine sand.

Bottom sediment surveys at the same stations in 1973 (Industrial BIO-TEST

Laboratories, Inc., 1973) revealed a similar sediment size distribution but

with a much larger sand fraction at Station 1. This was probably a result

of the fact that only a minimal 6000 gpm flow was maintained throughout most

of 1973 with occassional large discharges over a short period of time.

Though there is sufficient evidence to indicate that the Plant's discharge

scours the bottom and alters the sediment distribution, the size of the affected

area is small for sediment sizes greater than or equal to fine sand. Based

on the charts of bottom topography, this area extends approximately 400 ft

offshore and is about 250 ft wide.

10

FS z FINE SAND

G = GRAVEL to

FENCE * FS 0 ADMIN. .*

AREA .- FS S

F S

DISCHARGE SCREEN eG HOUSE t

FS

GUARD HOUSE


SCALE IN METERS OBSERVATION .

o 10 20 30 40 50 75 100 O BOOTHSRAO

SCALE IN FEET

0 50 100 200 300

PARKING

Figure 3.6. Size distribution of bottom sediments in the vicinity of the discharge outlet at Kewaunee Nuclear Power Plant on Lake Michigan, 28 August 1974.

.FE NC. FS FS = FINE SAND O ADMIN G = GRAVEL

AREA FS

F S :

to G

DISCHARGE SCEEN

HOUSE FS

GUARD HOUSE


SCALE IN METERS OBSERVATION.

0 10 20 30 40 50 75 100 O B OOTHI

SCALE IN FEET I .

0 50 100 200 300

PARKING

Figure 3.7. Size distribution of bottom sediments in the vicinity of the discharge outlet at Kewaunee Nuclear Power Plant on Lake Michigan, 12 November 1974.

Table 3. 1 Percent composition of sediment types and general description of sediment samples collected in Lake Michigan near the discharge outlet of the Kewaunee Nuclear Power Plant, 28 August 1974.

Percent Composition of Sedimert Type Location No.

and Fine Medium Coarse General Description Replicate Clay Silt Sand Sand Sand Gravel of Sediment Samples

1A <1 <1 6 13 12 69 Yellow-brown sand, rounded gravel

lB <1 <1 10 11 14 65 Yellow-brown sand, rounded gravel

2A <1 <1 86 10 3 1 Yellow-brown sand, rounded gravel

2B <1 <1 62 7 2 28 Yellow-brown sand, rounded gravel

3A 2(1) <1(<1) 95(98) 1(1) <1(<1) 2(<1) Yellow-brown sand, rounded gravel

3B 3 1 91 1 1 3 Yellow-brown sand, rounded gravel

4A 1 <1 28 4 6 61 Yellow-brown sand, rounded gravel

4B 1 <1 21 2 4 72 Yellow-brown sand, rounded gravel

5A <1(<1) <1(<1) 99(99) 1(1) <1(<1) <1(<1) Yellow-brown sand, rounded gravel

5B 1 <1 98 1 <1 <1 Yellow-brown sand, rounded gravel

(~A)

0

-1

r

Table 3.2 Percent composition of sediment types and general description of sediment samples collected in Lake Michigan near the discharge outlet of the Kewaunee Nuclear Power Plant, 12 November 1974.

Percent Composition of Sediment Type Location No.

and Fine Medium Coarse General Description Replicates Clay Silt Sand Sand Sand Gravel of Sediment Samples

22

18

11

14

1(1)

8

1

1

1

1(1)

23

10

7

10

<1(< 1)

<1

<1

<1

<1

<1(< 1)

25

36

34

39

1(1)

<1

3

<1

2

<1(<l1)

Brown

Brown

Brown

Brown

Brown

Brown

Brown

Brown

Brown

Brown

sand, sharp gravel

sand, sharp gravel

sand, sharp gravel

sand, sharp gravel

sand

sand

sand

sand

sand

sand

w

0

to M OI .,

1A

lB

2A

2B

3A

3B

4A

4B

5A

5B

1

2

1

1

2(2)

<1

2(2)

<1

5

<1

<1

2(<1)

<1

2

2

<1

7(3)

29

29

47

36

94(96)

90

94

97

95

90(94)

Addud BIO - TEST 2alaunc.


1. The discharge from KNPP is altering the lake bottom within a small

area 250 ft wide and extending 400 ft offshore.

2. The lake bottom is being scoured within 50 ft to 100 ft from the dis

charge outlet.

3. Sediment transported offshore by the discharge is apparently being

deposited within 150 ft to 300 ft from the discharge outlet.

15

9dadual BIO - TEST a6awe4-", I!&c.

V. References Cited

American Society for Testing and Materials. 1973. 1973 annual book of ASTM

Standards, Part II. Bituminous materials for highway construction, water

proofing, and roofing; soil and rock; peats, mossed, and humus; skid

resistance. Philadelphia, Pa. 1080 p.

Department of Commerce. 1974. Monthly bulletin of lake levels for August

November 1974. NOAA - National Ocean Survey, Lake Survey Center.

Shepard, F. P. and D. G. Moore. 1955. Central Texas coast sedimentation;

Characteristics of sedimentary environment, recent history, and diageneses.

Bull. Am. Assoc. Petrol. Geol. 39: 1463-1593.

16

Chapter 4

NEARSHORE CURRENTS, TEMPERATURE AND WIND

Richard G. Johnson


OF LAKE MICHIGAN NEAR KEWAUNEE NUCLEAR POWER PLANT:

PHYSICAL STUDIES


Ada.d- B BIO - T E S T /a e c

A)nda~d-ia BIO - TE S T .aatewo, Ic.

TABLE OF CONTENTS

List of Figures .................

List of Tables ..................

I. Introduction ....................


A. Current Measurements ....... B. Temperature Measurements . C. Wind Measurements .........

III. Results and Discussion .........

A. Current Measurements ...... B. Temperature Measurements .

C. Wind Measurements .........

IV. Summary and Conclusions .......

V. References Cited.................

i

Pag e

ii

iv

1

3

3 10 13

15

15 25 29

32

34

.......... .... ... ... ... ..

.......... .... ... ... ... . .

......... ..... ...*. . *. . . . .. ........ ... .. ... .. . . . . . ..

......... .. ... ... .. . . . . ..

......... ... ... ... ... . . ..

....... .... ... .... ... .....

Adad-ui1 BIO- TEST .a&ado&zie, A~c.

LIST OF FIGURES

No. Caption Page

4.1 Current meter mooring locations in Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant during 1974. . ............ . . . 4

4.2 Current meter and temperature recorder mooring used in Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant during 1974 . . . . . . . . . . 5

4.3 Recording current meter used for time-continuous current recording in Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant during 1974 ............... ............ 6

4.4 Progressive Vector Diagrams of time-continuous measurements of currents in Lake Michigan near the Kewaunee Nuclear Power Plant, July 1974 . . . . 8

4. 5 Window shade current drogue used in Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant during 1974.......... .... . . ..11

4.6 Recording thermograph used in Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant during 1974 ........ ..................... 12

4.7 Time-continuous current speed measurements at each mooring location in Lake Michigan near the Kewaunee Nuclear Power Plant, October 1974 . . . . 16

4.8 Monthly net water displacement in Lake Michigan and net wind displacement measured in the vicinity of the Kewaunee Nuclear Power Plant, JuneDecember 1974.................. . 20

4.9 Histogram of Lake Michigan current and wind direction recorded in the vicinity of the Kewaunee Nuclear Power Plant, June-December 1974........ . ..22

ii

ndatd~4 BIO - TEST a/ e .

LIST OF FIGURES (continued)

Caption

4.10 Histogram of Lake Michigan current and wind speed recorded in the vicinity of the Kewaunee Nuclear Power Plant, June-December 1974... . . . . . .. 23

iii

No.

Adad.aL BIST - TEBST a tS.

LIST OF TABLES

Caption

Comparison of time-continuous current meter and wind data recorded near the Kewaunee Nuclear Power Plant, June-December 1974...... .... . ..

Monthly means and ranges of time-continuous recordings of temperature in Lake Michigan near Kewaunee Nuclear Power Plant in 1974 .

iv

No.

4.1

4.2

Page

19

27

Chapter 4

NEARSHORE CURRENTS, TEMPERATURE AND WIND

Richard G. Johnson

I. Introduction

This field study was conducted during 1974 and represents the first year

of the continuous thermal impact investigation to document the operational

nearshore current and temperature conditions of Lake Michigan in the vicinity

of the Kewaunee Nuclear Power Plant (KNPP) . Field studies were conducted

for three years previous to this study to document the preoperational near

shore current and temperature conditions (Industrial BIO-TEST Laboratories,

Inc. 1971, 1972, 1973). The field study of nearshore currents and tempera

tures was identical to that of 1973. The specific objectives of the study were:

1. to measure the lake currents in the vicinity of KNPP from June to

December using moored current meters on a time-continuous basis at four

stations and current drogues on a periodic basis;

2. to describe the spatial and temporal nearshore circulation in the

vicinity of KNPP based upon the current measurements;

3. to measure the nearshore lake temperature from June to December

using time-continuous temperature recorders and monthly temperature profiles;

4. to describe the spatial and temporal nearshore temperature structure

in the vicinity of KNPP based upon the temperature measurements;

5. to collect sufficient representative temperature and current data for

use in the KNPP thermal plume model;

ndad wa BIO0 - T E ST .la/matew, Incx.

ndad-il BIO - TEST A/aa4w, A9c.

6. to measure the wind speed and direction in the vicinity of KNPP from

June to December on a continuous basis concurrent with the current and

temperature measurements; and

7. to describe the temporal wind patterns in the vicinity of KNPP based

upon the wind measurements.

2

Adadal1 BIO- TEST .la,9ic.


A. Current Measurements

1. Time-Continuous Current Meter Measurements

Current meter measurements were recorded as thirty-minute

averages continuously from 24 June to 17 December 1974 at each of four

mooring stations (Figure 4.1) . A current meter was located at a depth of

approximately 7 ft at each station, using the mooring system shown in

Figure 4.2. The instruments were serviced monthly. This included replace

ment of batteries, film and dessicant bags, and adjustment of the instrument

trim.

The current meter (ENDECO Type 105) is an axial flow, ducted

impeller instrument specifically designed for use in the nearshore zone

(Figure 4.3). Analog values of impeller rotation and magnetic bearing of the

instrument comprise the data which were recorded on 16 mm film. Each

instrument was calibrated prior to installation in a closely controlled flume

to determine threshold speed and accuracy of measurement. The calibrations

were conducted by BIO-TEST personnel at the Chesapeake Bay Institute of the

Johns Hopkins University. A threshold speed was determined for each current

meter. The lowest threshold speed among the current meters was 0.064 ft/sec

and the highest threshold speed was 0.12 ft/sec. Accuracy of speed measurement

was determined to be within +0.02 ft/sec of true speed. Current direction

accuracy was +5 degrees at threshold speed, +3.6 degrees above threshold

speed, and is resolvable to +1. 0 degrees.

3

I

Jjsa BIO-TEST ACa,.i., .

Figure 4.1. Current meter mooring locations in Lake Michigan in the vicinity

of the Kewaunee Nuclear Power Plant during 1974.

4

..9Ju.ia B10-TEST 9ALL.,op,.., .

CEDAR POST

S UR FACE

5ft

SUB SURFACE BUOY

76 CHAIN

RAILROAD

IS.S. WIRE

CURRENT METER

\ I.

RECORDER

CHAIN

S.S. WIRE

Figure 4.2. Current meter and temperature recorder mooring as used in Lake

Michigan in the vicinity of the Kewaunee Nuclear Power Plant

during 1974.

5

3nJ.dat BI0-TEST J'/.atore., Ac.

EXTERNAL CASE

-LEVEL

MAGNET LOCATOR FOR EXTERNAL FILM ADVANCE

"-TRIMMING WEIGHT COOK CLAMP TO MOORING

--4 3 1

INTERNAL COMPONENTS

CAMERA

REDUCTION GEAR TIMER CIRCUITRY

Figure 4.3. Recording current meter (ENDECO Type 105) used for timecontinuous current recording in Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant during 1974.

6

-0 2 I51

ROTOR BLADES

Ada~du' BIO - TEST akateam, Snc.

Time series data of hourly vector averages of current speed and

direction were used to construct plots of speed and direction versus time,

Progressive Vector Diagrams (PROVECS), Joint Frequency Tables of lake

current speed and direction and Persistence Tables of current speed and

direction.

The PROVECS were formed by connecting the time series of

velocity vectors for a current meter record. An example is presented in

Figure 4.4. The vectors were connected head to tail and produced a diagram

that resembles the horizontal projection of a water particle trajectory.

However, it should be kept in mind that a PROVEC depicts the history of

water motion past a given point and is not a representation of a trajectory.

Intercomparison of the PROVECS for a given month permits

determination of the relative velocity and direction of flow past each mooring

location for any period chosen. The asterisks and adjacent numbers on the

plots indicate the beginning and date of each measurement day. Close

bunching of the asterisks infers slow current for that period, whereas

increased distance between asterisks infers faster current. Dashed lines

indicate missing data. Each PROVEC was plotted on the same scale to.

facilitate comparisons.

Joint Frequency Tables show the frequency of joint occurrence

of speed (by speed class) and direction (by direction sector). The column

on the right of each table is the frequency of occurrence of each direction

as a percentage of the total observations for that period. The bottom row

7

~27 26

252

19

7 S S

OFFSHORE SURFACE STATION

0 4 8

Feet ( 103)

JULY 1974

SOUTH STATION

Figure 4.4. Progressive Vector Diagrams (PROVECS) of time-continuous measurements of currents in Lake Michigan near the Kewaunee Nuclear Power Plant, July 1974. Asterisks and adjacent numbers indicate the beginning and date of each measurement day.

8

NORTH STATION

NN A 12 6

4

INTAKE STATION

feddual BIO0 - T E S T.1 au , c

2,

30

m 29

16

to

represents the frequency of occurrence of speed by class also as a percentage

of the total observations. Entries in the table represent the frequency of

* occurrence of the various velocity classes (speed and direction).

Persistence refers to the number of consecutive hours that a given

parameter fell within a specified direction or speed class over a specified

time period (monthly). In each table the left column labeled "persistence"

lists the persistence time in hours and the top row lists the direction or

speed class . The row labeled "maximum" contains the greatest persistence

(hours) observed for that class. The row labeled "total" contains the number

of observations for that class. The left column labeled "percentiles" lists the

percentiles of the total number of observations in each class which persisted

for the number of hours (or less) shown in that respective row. For example,

a "4" in the 50 percentile row and the NE direction is to be interpreted as,

"50 percent of the observations in the NE class had a persistence of 4 hours

or less." The row labled "sample size" indicates the number of hours of data

contained in each class.

2. Current Drogue Measurements

Drogue measurements were attempted monthly May through November

to estimate spacial variations in current speed and direction in the vicinity of

the KNPP site. Drogue studies during May, July, September and November were

conducted for the purpose of assessing the presence of eddy currents in the

vicinity of the promontory (Chapter 5, Physical Studies). These studies were

confined to the region around the promontory and within 3000 ft from shore.

9

ndad1ad BIO - TEST .alaneT, Ac.

During June, August and October drogue studies were conducted in the vicinity

of each of the current meter stations (Figure 4.1) for the purpose of assessing

spatial variations of the current.

Window shade drogues (Figure 4.5) were used which consisted of

a 5 ft x 5 ft polyethylene panel weighted at one edge by an iron pipe and

attached at the opposing edge to a length of conduit. The panels were suspended

beneath the surface buoys to measure currents at the surface and at a depth of

10 ft. The locations of the drogues were periodically determined by a precision

navigation system (Motorola Mini-Ranger).

B. Temperature Measurements

1. Time-Continuous Temperature Measurements

Continuous time series temperature measurements were made con

currently with the current measurements. One ENDECO Type 109 recording

thermograph (Figure 4.6) was attached to each mooring directly beneath the

current meter. Two thermographs recorded hourly averaged temperature and

two thermographs recorded half-hourly averaged temperature on 16 mm film

with a resolution of 0. 1 C and an accuracy of +0. 2 C. The time constant of

the instrument is 10 min. The thermographs were serviced simultaneously

with the current meters with the replenishment of new batteries, film and

dessicant bags.

Hourly averages of temperature versus time were plotted for each

month and each station. The maximum, minimum and mean temperatures

were determined for each month and compared by station and month.

10

MARKER FLAG

STYROFOAM FLOAT

POLYETHYLENE PLASTIC -

THIN WALL ....................................... ............................................... CONDUIT ............................................... ............................................... ............................................... ............................................... ............................................. ............................................... ............................................. ...............................................

............................................... ................................................ ............................................... ............................................... ............................................... ;!ttml ................... ............................................... ............................................... ................................................ ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ................................................ ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ................................................ ............................................... ............................................... ................................................ ............................................... ............................................... ............................................... ............................................... ............................................... ................................................ ............................................... ................................................ ............................................... ............................................... ----------------- -------------------------- t R O N P IP E

WINDOW SHADE DROGUE Figure 4.5. Window shade current drogue used in Lake Michigan in the

vicinity of the Kewaunee Nuclear Power Plant during 1974.

11

Adaad BIO -TEST .aut w a

Sded1id BIO - TEST 2a9,c.

MARKER FLAG

r--STYROFOAM FLOAT

POLYETHYLENE PLASTIC --

THIN WALL CONDUIT ............................................... ................................................ ............................................... ............................................... ............................................... ................................................ ............................................... ................................................ ...............................................

............................................... ............... ............................................... ............................................... . *" *" * ....................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ................................................ ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ................................................ ................................................ ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ............................................... ----------------------------- ---------------- t R O N P IP E

WINDOW SHADE DROGUE

Figure 4.5. Window shade current drogue used in Lake Michigan in the vicinity of the Kewaunee Nuclear Power Plant during 1974.

11

0

INTERNAL COMPONENTS

TIMER CIRCUITRY-

CAMERA

THERMOMETER

,..

N

Figure 4.6. Recording thermograph (ENDECO Type 109) used in Lake Michigan

in the vicinity of the Kewaunee Nuclear Power Plant during

1974.

9 .4

-I

6Z- LIT

k aAded1 BIO - TEST Jaalouw',a.

2. Temperature Profile Measurements

Temperature profile measurements of the ambient water mass in

the vicinity of the KNPP were attempted on a monthly basis using a precision

thermistor temperature probe (M & F Engineering). This instrument provided

a resolution of 0.01 C and an accuracy to within 0.05 C. The position of

measurement locations were determined using a precision navigation system

(Motorola Mini-Ranger).

Temperature measurements were made along transects perpendicular

to the shoreline for the purpose of assessing the ambient temperature structure.

Along each transect, water temperature was measured at one meter depth

intervals at each of the locations. Transects were located to best determine

the vertical ambient thermal structure of the water. Vertical temperature

profiles were plotted for each transect and isothermal contours were drawn.

C. Wind Measurements

Wind measurements were continuously recorded from 23 July to

14 December 1974 near the KNPP observation building at a height of 10 m

above grade (75 ft above the water surface). A mechanical weather station

(Meteorology Research Incorporated Model 1071) was used for these measure

ments. Wind direction and wind run (the distance of wind which passes the

instrument) were continuously recorded on strip chart paper. The weather

station was serviced monthly which included the replacement of batteries

and strip chart paper. The threshold of the instrument is <1.1 ft/sec. Wind

run was recorded with an accuracy of +2% and is resolvable to 0.5 mile.

Direction was recorded with an accuracy of 3.6 degrees and resolvable to

13

9me~dia1 BIO - TEST 2a kaee, Ic.

15 degrees.

Time series data of hourly vector averages of wind speed (wind run

per unit time) and direction were used to construct plots of speed and direction

versus time, Progressive Vector Diagrams (PROVECS), Joint Frequency Tables

of wind speed and direction and persistence tables of wind speed and direction.

14

.9n .hia BI10- T E ST Ja~~)


A. Current Measurements

1. Time-Continuous Current Meter Measurements

The time-continuous current data described herein represents a

94 percent return of valid data for the entire measurement program.

A visual comparison of the current speed data obtained at each

station shows good correlation among the stations during each month. A

typical example of the degree of speed correlation is shown in Figure 4.7.

The fluctuations in speed as measured at each station were strongly correlated

in time but differed slightly in magnitude. The speeds measured at the

Offshore Surface station were generally faster than those at the other stations.

Typical speeds ranged from 0.1 to 0.4 ft/sec and occasionally reached 0.6 ft/sec.

The maximum speed recorded was 1.2 ft/sec which occurred during November

at the Offshore Surface Station. The direction of flow at individual stations

was sometimes observed to be different from the general direction of flow of

the water mass; these were localized effects due to deflection caused by the

bottom topography. These directional differences indicate a temporary inter

ruption of the general water movement at a given station. (cf. PROVECS

in Appendix 4-B).

The PROVECS for each data record are included in Appendix 4-B.

The PROVECS of the data records from each station are plotted together for

15

dtadial BIO - TEST 2AaAde, Ac.

NORTH STRTION

INTAKE STRTION

SOUTH STRTION

OFFSHORE SURFRCE STRTION

Figure 4.7.

OCTOBER 1974

Time-continuous current speed measurements at each mooring

location in Lake Michigan near the Kewaunee Nuclear Power Plant,

October 1974.

16

9dzduail BIO - TEST .ala4,eu, In.

each month. The plotting scale is 2 x 104 ft/inch for each record. Consequently,

the records may be directly compared both among stations and among months.

Figure 4.4 shows the PROVECS constructed from each of the July

current records. Due to an instrument malfunction, the current record at the

South Station begins on 23 July. By comparing the individual PROVECS for various

time periods, it is seen that the water body moves essentially as a homogeneous

mass. For example, on 25 July approximately mid-morning, the current at all

stations was moving toward the NE. Simultaneously, at all but the Offshore Surface

Station, the current changed directions and began moving toward the NW. A

few hours later, the current again turned toward the NE at all stations. For a

given time period, current speeds and directions among the stations differ

somewhat probably due to bathymetric influences. However, changes in speed and

direction of flow generally occur at all stations at the same time. A comparison

of these monthly diagrams both among themselves and with other data (such as

wind and bathymetry) provides insight into the nature of the flow and how it is

affected by other parameters. On 25 July, the same shifts in wind direction

are found as described above.

The net water displacement, the direction of net displacement,

the speed of net displacement, the average current speed and the individual

record length were determined for each monthly current record and for the

six-month period from June through December. These data are shown in Table

4.1. The net displacement of water past KNPP was generally shore-parallel

toward the northeast at a mean speed of from 0.2 ft/sec to 0.08 ft/sec. Typical

17

Adud-iwBa BIO- TEST 9aalo, Inc.

monthly average current speeds ranged from 0.17 ft/sec to 0.28 ft/sec and

generally increased each month from June to December. Typical monthly net

displacements were between 1.0 x 10 5 and 2.0 x 105 ft. For the six-month

period, the Intake and South Station records revealed the greatest net displace

ment.

Figure 4.8 graphically shows the net monthly water displacement

at each station. The length of the arrow is proportional to the displacement

and the direction of the arrow indicates the direction of displacement with

respect to True North. The nearshore circulation is more clearly understood

by considering Figure 4.8 and Figure 4.1 together. When water moves past

the South Station toward the northwest, it impinges on the shoaling contours

and is deflected northward and finally northeastward by the promontory.

The direction of net displacement at the South Station during each

month was toward the northwest. As a result of this and the bathymetric effects,

the net displacement at the Intake Station was toward the northeast and finally

toward the eastsoutheast. Probably the eastward deflection of current at the

promontory, as shown in the Intake Station records, played a significant role

in reducing the total amount of water which reached the North Station. The

six-month net displacement measured at the North Station was slightly more

than half that at the Intake and South Stations and the average current speed

and speed of net displacement were also considerably smaller than those at

the Intake and South Stations.

18

0

Table 4.1. Comparison of time-continuous current meter and wind data recorded near the Kewaunee

Nuclear Power Plant, June-December 1974.

Month - 1974 June-December 1974

Parameter Station June July Aug. Sept. Oct. Nov. Dec. 6 Month Total

Net Displacement North 0.183 1.28 0.946 0.772 1.545 0.781 0.566 4.325

(feet (105)) Intake 0.218 2.177 1.194 1.071 1.728 2.126 1.517 7.519

South -a 0.690 1.359 1.469 1.564 1.682 0.971 7.393

Offshore surface 0.347 3.193 1.049 0.640 0.505 1.456 1.058 2.760

Wind 74.600 137.340 22.460 61.510 178.800 44.110 443.479

Direction of Net North 15 340 338 49 28 38 210 10

Displacement Intake 346 17 10 65 71 100 122 64

(0 True) South - 359 324 337 316 303 302 40

Offshore surface 358 18 22 291 5 174 180 20

Wind - 47 22 5 351 23 128 27

Speed of Net North 0.034 0.049 0.035 0.030 0.058 0.030 0.057 0.029

Displacement Intake 0.040 0.083 0.052 0.041 0.065 0.082 0.106 0.051

(ft/sec) South - 0.086 0.051 0.057 0.058 0.065 0.068 0.058


Wind - 10.11 5.82 2.81 7.00 6.99 3.82 5.23

Average Current North 0.13 0.14 0.15 0.19 0.17 0.17 0.24 0.17

Speed Intake 0.18 0.22 0.21 0.24 0.20 0.21 0.28 0.22

(ft/sec) South - 0.13 0.17 0.23 0.21 0.19 0.28 0.20


Wind - 14 14 13 14 16 20 15

Record Length North 149 744 742 719 742 720 276 4092

(Hours) Intake 151 728 640 716 741 717 399 4093

South - 221 740 716 741 718 397 3533

Offshore surface 149 743 741 716 740 616 395 4100

Wind - 205 655 222 244 710 321 2357

a - = No data were collected during this time period.

d ~10 I- T ES T 2aa~uo',.9~c

I /WIND

NORTH STATION

INTAKE STATION

SOUTH STATION

OFFSHORE SURFACE STATIONIp

I I I I I I I JUN JUL AUG SEP OCT NOV DEC

Figure 4.8.

N

Feet (iO')

0123

NET DISPLACEMENT JUNE-DECEMBER 1974

Monthly net water displacement in Lake Michigan and net wind

displacement measured in the vicinity of the Kewaunee Nuclear

Power Plant, June-December 1974. (Wind displacement is plotted

1/10 the scale shown. The length of the arrow is equivalent

to the net displacement and the direction of the arrow is

equivalent to the direction of net displacement with respect to

True North) .

20

Sgdaea' BIO - TEST .a&e&, c.

Monthly Joint Frequency Tables of lake current speed and direction

for each data record are contained in Appendix 4-C. During each month each

current record generally showed a bimodal directional characteristic (the occurrence

of two predominant current directions). The predominant speeds were found to

occur within the 0.1-0.24 ft/sec speed class.

Figure 4.9 is a graphical representation of the six-month distribution

of current direction at each station. The bimodality is evidenced by the peaks

located near the NNE-NE and the SSW-SW directions. At each station, there is

also a third but smaller peak near the NW-NNW direction. Figure 4.10 is a

graphical representation of the six-month distribution of current speed at each

station. The peak at the 0.1-0.24 ft/sec speed class is evidence of the predominant

speeds recorded. The North Station distribution shows a second peak nearly equal

in magnitude at the <0.1 ft/sec speed class.

Persistence tables for current direction and current speed are con

tained in Appendices 4-D and 4-E, respectively. The greatest persistence of

current in a single direction was 42 hours toward the NNW. This occurred during

November at the South Station. For four out of six months the greatest monthly

direction persistence maximum occurred at the South Station in the direction

towards NNE. Direction persistence at all stations increased from June to

December. Over the six-month period, the most frequently observed monthly

persistence maximum at each station was in the direction toward NNE.

Appendix 4-E contains the current speed persistence tables for data

collected at each station from June through December. The greatest speed

persistence observed during the six-month period was 55 hours at the North

21

DI RECTION

20 N NINE I NE IENEI E I ESEI SE SSE S |SSW SW IWSW W IWNW NW NNW

15 Wind

10

5

0

20 N orth Station

I0 15 -1

0

20

15

10

5

0

20

15 IO

5

0

20

15

10

5

0

Figure 4.9.

DIRECTION Histogram of Lake Michigan current and wind direction recorded

in the vicinity of the Kewaunee Nuclear Power Plant, June

December 1974.

22

Intake Station

w U

C) z w

0

0

W

z

0-

South Station

Offshore Surface Station

Adad B BIO - T E ST .Ja, c.

A~dadsi' BIO-TEST .1a0oatTESc.

Wind40

30

20

10

0

50

W z w

C

U.'

z w

a

Figure 4..10.

40

30

20

O0

0

40

30

20

10

a

40

30

20

10

0

40

30

20

10

0-

I

North Station

South Station

Offshore Surface Station

<.1 .1-.24'.25-.39'.40-.54'.55-j69'.70-.84' >.85 CURRENT SPEED

Histogram of Lake Michigan current and wind speed recorded

in the vicinity of the Kewaunee Nuclear Power Plant, June

December 1974.

23

< 1 '1-6 ' 6-12 ' 12-19 ' 19-28 " 28-35 ' >35 WIND SPEED

CURRENT SPEED

<.1 .1-.241.25-.391.40-.541.55-.691.70-.841 >.85

ake Station

,-*----------i----------------i------------- -r

Int

"" " I"

1!111111112= 9

***

AB da0 BIO- TEST 2a~a&na, Ac.

Station. This occurred between 3 and 6 November and the speed class was

0.1-0.24 ft/sec. Speeds within the 0.1-0.24 ft/sec class were the most frequently

observed monthly maximum persistence over the six-month period. The Offshore

Surface Station consistently recorded the greatest speeds having a persistence of

one hour or more. The greatest persistence speed class observed was the

>0.85 ft/sec class for a maximum duration of five hours at the Offshore Surface

Station on 8 December. Speed persistence increased from June to December.

2. Current Drogue Measurement

For each day of drogue measurements, the data were plotted

(Appendix 4-F) and the corresponding speeds and direction of travel were

determined and listed (Appendix 4-G). The results of the studies during May,

July, September and November are presented in Chapter 5. These studies

investigated the spatial variations in current speed and direction and the

presence of eddy currents in the vicinity of the promontory. The studies

during June, August and October which were intended to assess the spatial

variations in current speed and direction over a larger area in the vicinity

of KNPP are considered here.

The data show, as do the time-continuous current measurements,

that the water body in the vicinity of KNPP was generally spatially homogeneous

in speed. However, the drogues released at different stations often moved in

slightly different directions, an effect which is probably due to the bottom

topography. Speeds measured at the surface were faster than those at a depth

of 10 ft.

24

nd dual BIO - TEST 2a at4ewi, Inc.

During the June and October studies, direction of net drogue travel

at the surface and at 10 ft differed by only a few degrees while during August,

at the North and South Stations, the angular difference was approximately

90 degrees. Upwelling as seen by the uptilting of the isotherms measured

on the same day was responsible for this large angular deviation.

Little difference in direction of net water flow as determined by

the drogues and the current meter measurements was observed. The speed

of current flow as determined by the movement of the drogues was usually greater

than that determined by the current meters, which suggests that the drogues

were somewhat wind sensitive. However, it is difficult and of ambiguous sta

tistical significance to make direct comparisons of drogue and current meter data

except during those rare instances when the drogue physically moved past

the current meter during a given study. In such a case, it is considerably

more certain that the two devices are in fact measuring the same parcel of water.

Water that has moved past a moored instrument at a given time is not necessarily

moving with the same speed or in .the same direction once it has passed that

instrument. Consequently, it is not surprising that differences occurred between

flow determined by drogue studies and flow determined by current meter data.

However, it is important to note that the results of the drogue and moored

current meter studies are in good agreement.

B. Temperature Measurements

1. Time-Continuous Temperature Measurements

The time-continuous temperature data herein described represents

an 88 percent return of valid data for the entire measurement program. The

25

Ad~1ial B 1 - T E S T .ia4ae, c.

time-continuous temperature data (Appendix 4-H) show good correlation among

the four stations. Fluctuations in temperature occurred almost simultaneously

at all stations which further attests to the homogeneity of movement of the water

body as indicated by the time-continuous current data. Maximum, minimum and

mean values of temperature from June through December 1974 are tabulated in

Table 4.2. When making comparisons among the various stations, consideration

must be given to the length of each record. Records of significantly different

length contain data collected during different time periods and, therefore, cannot

be directly correlated. Data in Table 4.2 show that the period of greatest monthly

temperature range occurred during July (AT = 13.7 C) at the Offshore Surface

Station.

A comparison of the monthly temperature range recorded among the

stations shows that for records of approximately equal record length, with the

exception of July, the range was always highest at the Intake Station. Differences

in the monthly temperature range among stations for a given month were frequently

as large as 1.2 C and were always as large as 0.5 C. The monthly mean tempera

tures among stations of approximately equal record length were within 0.5 C of

one another. The maximum temperature recorded was 21.7 C which occurred at

the Offshore Surface Station on 22 July 1974. The minimum temperature recorded

was 0.2 C which occurred at the South Station on 9 December 1974.

During July and August, periods of rapid temperature decrease

occurred. The maximum rate of decrease occurred on 15 August between 1400

and 2400 hrs. At the North Station during this period, the temperature decreased

6.5 C in a 10 hour period. The presence of the thermal plume is frequently

26

0

Table 4.2. Monthly means and ranges of time-continuous recordings of temperature in Lake Michigan near Kewaunee Nuclear Power Plant in 1974.

Mooring North Intake South Offshore Surface

Record Record Record Record Temperature Length Temperature Length Temperature Length Temperature Length

Month (*C) (hr) (0c) (hr) (*C) (hr) (0C) (hr)

June Mean 13..2 168 13.0 136 13.0 168 12.6 168 Range 12.7-13.9 12.7-13.5 11.9-13.6 11.7-13.4

July Mean 11.0 744 10.8 742 10.8 528 11.8 744 Range 6.5-16.8 6.8-18.4 7.3-16.1 8.2-21.9

August Mean 13.4 742 13.0 743 14.3 83 13.3 661 Range 10.0-19.6 8.9-19.1 13.5-15.0 9.3-17.8

September Mean 13.3 718 13.2 719 13.4 718 -a Range 6.8-17.4 6.4-17.3 7.2-16.9

October Mean 7.9 742 8.0 743 8.0 743 7.8 415 Range 6.6-10.1 6.2-10.4 6.3-10.2 6.7-8.9

November Mean 6.3 721 6.4 719 6.0 720 7.4 462 Range 2.2-9.7 2.0-10.3 1. 8-9. 5 4.4-8.7

December Mean 1.9 276 2.7 401 2.2 397 -

Range 0.5-4.3 0.8-5. 7 0.2-4.6

a No data were collected during this time period.

N -J

0 -" rn -4

visible in the temperature records. For example, on 12 October, the current

was moving toward the southwest at all current meter stations and a narrow

high temperature spike is visible in the South Station temperature record, but

is absent from the North and Intake Station temperature records. Similarly,

on 4 and 9 December during a northeastward current, temperature spikes are

visible in the Intake and North Station temperature records but are absent from

the South Station record.

2. Temperature Profile Measurements

Plots of the monthly temperature profile data are presented in Appen

dex 6-A. The maximum ambient surface temperature measured during the month

ly profiles was 19.1 C which occurred on 23 July and the minimum temperature

was 7.6 C on 23 October.

The first ambient temperature profile measurements were made on

23 July. These measurements revealed a well stratified water column with a

vertical temperature gradient of -0.35 C/m, at 1 km offshore. The horizontal

surface temperature gradient in the offshore direction was approximately

-1 C/km.

On 27 August, the maximum ambient surface temperature was 15.4 C.

The horizontal and vertical temperature gradients at this time were -0.2 C/km

and -0.3 C/m, respectively. On 25 September, profile measurements showed

a smaller horizontal temperature gradient compared to July and August. The

maximum surface temperature was 12.9 C and the vertical temperature gradient

was approximately -0.2 C/m.

28

A~ut-s B BIO - T E ST a akeIc

%cdud-uw' BIO - TEST aate6,$Ic.

The fall overturn apparently occurred between the September and the

October temperature measurements. The 23 October profiles showed the water

to be nearly isothermal. The maximum surface temperature was 8.5 C. Temp

erature measurements on 12 November revealed no significant changes in the

thermal structure of the water column. Horizontal surfac'e temperatures in

November ranged from 8.7 to 8.9 C within 3 km distance offshore.

C. Wind Measurements

The time-continuous wind data described herein represents a 68 percent

return of valid data for the entire measurement program.

A visual comparison of the wind data obtained at the site is presented

in Appendix 4-I. Wind speed and direction are plotted against time and are

shown with PROVECS of the same data. Typical wind speeds ranged from 10

to 30 ft/sec. The maximum speed recorded was 54 ft/sec which occurred on

26 November.

The net wind displacement, the direction of net displacement, the speed

of net displacement, the average wind speed and the individual record length

were determined for each monthly wind record and for the five-month period from

July through December. These data are shown in Table 4.1. The net displace

ment of wind past KNPP was generally toward the northeast at a mean speed of

from 2 ft/sec to 10 ft/sec. The monthly average wind speed ranged from 13 ft/sec

tp 20 ft/sec and generally increased each month from July to December. Monthly

net displacements ranged between 44 x 105 and 178 x 105 ft.

Comparison of the net displacements of wind and water during periods

of maximum record length implies typical monthly net displacements. Values of

29

knda 10 BIO- TEST 2a/alaw 9,Ic.

0.054 ft/sec and 6.4 ft/sec appear to be representative for current and wind speeds

of net displacement. Net displacements for similar time periods show 1.44 x 105

and 175 x 105 ft to be representative monthly displacements of current and wind,

respectively. From these comparisons we may infer that for every 100 ft of

wind displacement there is an approximate displacement of 1 ft of water.

Figure 4.8 graphically shows the net monthly wind displacement for each

month. The length of the arrow is proportional to the displacement and the

direction of the arrow indicates the direction of displacement with respect to

True North. The predominant direction of net displacement was toward the north

east. Comparison of the directions of net displacement among wind and current

show good agreement.

Monthly Joint Frequency Tables of wind speed and direction are contained

in Appendix 4-J. Wind direction measured during October-December became

increasingly bimodal towards the N-NNE and NW-NNW.

Figure 4.9 is a graphical representation of the five-month distribution

of wind direction. The modality is evidenced by the peaks located near the N and

the NE directions. On the five-month scale, it is obvious that the bimodality

observed in the current records is not clearly defined in the wind records.

However, the predominant direction of the wind is towards the north and varies

between NW and the SE. Winds infrequently blow toward the SW. In the same

graph, the currents show predominant directions toward SSW and NNE-NE. These

directions are directly related to the shoreline and the bathymetric contours of

the study area. The SSW current directions occur during winds toward the ESE-SE

while NNE-NE currents coincide with generally northward moving wind.

30

Andia1 BIO - TEST .Zoalw ni, nc.

With the exception of August, the predominant wind speed class was

12-19 ft/sec. Figure 4.10 is a graphical representation of the five-month distri

bution of wind speed. The peak at the 12-19 ft/sec speed class is evidence of

the predominant speeds recorded. The speed distribution shows second peaks

nearly equal in magnitude at the 6-12 ft/sec and 19-28 ft/sec speed classes.

Persistence tables for wind direction and wind speed are contained in

Appendices 4-K and 4-L, respectively. The direction classes of greatest persistence

are concentrated in the NE and E-ESE sectors. The greatest persistence of wind

in a single direction was wind toward the ESE for 18 hours which occurred on

8 December. It is interesting to note that the greatest persistence current speed

was also observed on 8 December. The persistent wind direction probably was

directly responsible for producing conditions which were conducive to the high

current speeds.

The wind speed of maximum monthly persistence for the first four months

(July-October) was in the 12-19 ft/sec class and during the November and

December the maximum persistence was in the >35 ft/sec class. The greatest

persistence of wind speed was 24 hours for >35 ft/sec speeds which occurred

on 1 December 1974.

31

nduda1' BIO - TEST 2a,)Ac.


1. The data collected describe the spatial and temporal nearshore circula

tion and temperature structure and the wind distribution in the vicinity of KNPP

for the June-December 1974 measurement period.

2. The data collected were sufficiently representative to provide useful in

put into the KNPP thermal plume model.

3. The water mass movement in the area of KNPP is spatially homogeneous

in speed. The direction of flow is influenced by the bottom topography and the

prevailing local winds.

4. The promontory in the region of the condenser cooling water intake plays

a major role in the general water circulation in the vicinity of the KNPP.

5. The net displacement of water past the KNPP was generally shore-parallel

toward the northeast at a typical mean speed of 0.054 ft/sec. Average monthly

current speeds range between 0.17 ft/sec and 0.28 ft/sec. The maximum current

speed recorded was 1.2 ft/sec.

6. The greatest persistence of current in a single direction was 42 hours to

ward the NNW and the greatest persistence of current speed was 55 hours for

speeds within the 0.1-0.24 ft/sec. class.

7. Periods of greatest temperature range occurred during July. This range

was found to be as great as 13.7 C.

8. A maximum temperature of 21.7 C was recorded during July at the Off

shore Surface Station and a minimum temperature of 0. 2 C was recorded during

December at the South Station.

32

9. Monthly mean temperatures at all stations differed by 0.5 C or less.

10. Net wind displacement past the KNPP was generally toward the northeast

at a typical speed of displacement of 6.4 ft/sec. Average monthly wind speeds

ranged from 13-20 ft/sec. The maximum wind speed recorded was 54 ft/sec.

11. The greatest persistence of wind in a single direction was 18 hours to

ward ESE and the greatest persistence of wind speed was 24 hours for speeds

>35 ft/sec.

33

Adusia BIO - T E ST .&waow, c.

Ac/~daia BIO - TEST a~onaoet, c

V. References Cited

Industrial BIO-TEST Laboratories, Inc. 1972. Preoperational thermal monitoring program of Lake Michigan near Kewaunee Nuclear Power Plant, JanuaryDecember 1971. (IBT No. W9438). Report to Wisconsin Public Service Corporation, Green Bay, Wisconsin. 191 p.

. 1973. Preopoerational thermal monitoring program of Lake

Michigan near Kewaunee Nuclear Power Plant, Second Annual Report, January-December 1972. (IBT No. 1808). Report to Wisconsin Public Service Corporation, Green Bay, Wisconsin. 561 p.

. 1974. Preoperational thermal monitoring program of Lake

Michigan near Kewaunee Nuclear Power Plant, Third Annual Report,

January-December 1973. (IBT No. 643-03208). Report to Wisconsin

Public Service Corporation, Green Bay, Wisconsin. 1275 p.

34

9idedd2ial1 BIO- TEST 2aaa4w&w,kce

Chapter 5

EDDY CIRCULATION

William C. Williams


PHYSICAL STUDIES


A2Kdaital BIO - TEST 1/aoaeze-, Ie.

TABLE OF CONTENTS

List of Figures ...............

Introduction ..................

Field and Analytical Procedures

Results and Discussion ........

Summary and Conclusions .....

References Cited ...............

...................

............... ........

..... ************ ******.

1

I.

II.

III.

IV.

V.

Page

ii

1

2

4

8

9

dad,2~ial BIO - TEST A alaw, c.

LIST OF FIGURES

No. Caption Page

5. 1 Window shade drogues used in Lake Michigan for the study of currents near the Kewaunee Nuclear Power Plant during 1974 .... ................................................ 3

5. 2 Schematic illustration of the eddy circulation associated with northward currents in Lake Michigan near the Kewaunee Nuclear Power Plant ..................................... 6

5. 3 Schematic illustration of the deflection of southward currents in Lake Michigan by the promontory near the Kewaunee Nuclear Power Plant ................ o ......... ....... 7

ii

Sndia1 BIO - TEST a, c.

Chapter 5

EDDY CIRCULATION

William C. Williams

I. Introduction

Presented in the Final Environmental Statement for the Kewaunee Nuclear

Power Plant (Atomic Energy Commission, 1972) is a discussion of the possibility

that the promontory which projects into Lake Michigan just south of the Plant's

cooling water discharge outlet might introduce a perturbation into northward

currents and cause an eddy circulation to develop on the north side of the

promontory. The effect that this eddy would have on the thermal plume from

Kewaunee Nuclear Power Plant (KNPP) was not known. For this reason, a

small scale study was conducted with the objective of establishing whether or

not an eddy circulation develops near the promontory in the presence of north

ward or southward alongshore currents.

1

9Andiaal BIO - TEST .oK,)Ac.

I. Field and Analytical Procedures

On 28 May, 23 July, 25 September, and 12 November 1974, drogues were

deployed near the promontory and tracked for several hours. The locations of

the drogues were determined periodically by means of a Motorola Mini-Ranger

Navigation system, Model 1 (MRS-1) which has an accuracy of greater than

+ 10 ft at a range up to 20 nautical miles. The type of drogue that was used is

known as a window shade drogue. It consists of a weighted sail beneath an

attached buoy (Figure 5. 1). The sail can be placed at any desired depth and the

current speed and direction determined by tracking and timing the position of

the surface buoy. In a comparison of several types of drogues, it was deter

mined by Monahan et al (1973) that a window shade drogue best followed the

current.

Drogue trajectories were plotted and drogue speeds and directions were

tabulated. The drogue trajectories were used as an estimate of the current

patterns near the promontory.

2

9Sndu4Ba 1 - TEST 9"ale, Ic.

MARKER FLAG

STYROFOAM FLOAT

POLYETHYLENE PLASTIC ---.

-THIN

WALL

THIN WALL --- ..................... CONDUIT .............. ......................... ......... ........... .. .................. .......................

........... ........... .................

X .......... ......................... ........ ....

..........

................. ...................... ......... ..................

............... ..........

....................... ' * ................................... RON PIPE

WINDOW SHADE DROGUE

Figure 5. 1 Window shade drogues used in Lake Michigan for the study of currents near the Kewaunee Nuclear Power Plant during 1974.

3

Adadza' BIO - TEST aae c.


All data on drogue speed and direction are tabulated in Appendix 5-A.

Illustrations of individual drogue trajectories are presented in Appendix 5-A,

Figures 1 through 7.

The alongshore current on 28 May was northward at 0. 30 fps. Only one

drogue trajectory indicated the presence of an eddy current by turning north

west towards the shore. Thus, it is not clear whether an eddy current was

weakly developed or not present at all.

The alongshore current on 23 July was northward at 0. 42 fps. For these

current conditions, the drogue trajectories within 1600 ft from shore (six out

of ten drogues) indicated the presence of an eddy current on the north side of

the promontory. Drogues further offshore than 1600 ft followed the ambient

current. The eddy circulation may have been well developed in this case

because the alongshore current speed was greater in July than in May.

The surface current on 25 September was southward at approximately

0. 25 fps. The drogue trajectories indicated that the current was deflected by

the promontory toward the southeast. There was no evidence of an eddy circu

lation on the south side of the promontory.

The drogue trajectories on 12 November indicated a westward surface

current near the promontory. This was a result of westerly winds and the

thermal plume (Chapter 6). That is, the current due to the thermal plume dis

charge near the promontory helped to carry the drogues westward away from

the shore. These current conditions were not suitable for evaluating the

4

A~'idaial BIO - TEST 2amat4euic.

current patterns near the promontory.

Temperature measurements were made in conjunction with thermal plume

surveys (Chapter 6) in order to independently define the eddy circulation via

temperature patterns. However, this effort was not successful since temper

ature patterns which might indicate an eddy could not be separated from those

associated with the thermal plume.

The results of the study are summarized in Figures 5. 2 and 5. 3. These

figures show that an eddy circulation in the lee of the promontory is associated

with northward currents but not southward currents. The eddy has a radius of

approximately 1200 ft and includes an area of about 104 acres. However,

based on May and July data, the presence of an eddy circulation may also de

pend on the speed of the northward current.

5

Snzdud 1 BIO - TEST Aae, .

Figure 5. 2 Schematic illustration of the eddy circulation associated with northward currents in Lake Michigan near the Kewaunee Nuclear Power Plant.

6

ddu/ndai4 BIO - TEST .la~maldae,%

Figure 5. 3 Schematic illustration of the deflection of southward currents in Lake Michigan by the promontory near the Kewaunee Nuclear Power Plant.

7

deda10 BIO- TEST 2aaI kd,Ic.


1. An eddy circulation north of the promontory was associated with

northward currents and affected an area of approximately 104 acres.

2. Southward currents were deflected to the southeast by the promontory.

There was no evidence of an eddy circulation associated with a southward

current.

3. Temperature measurements were not successful in defining an eddy

circulation pattern.

8

j2ka~~ a 0 BIO- TEST Aa Pabum,$Ic.

V, References Cited

Atomic Energy Commission. 1972. Final Environmental Statement Related to Operations of the Kewaunee Nuclear Power Plant of Wisconsin Public Service Corporation. Docket No. 50-305. U. S. Atmoic Energy Commission, Directorate of Licensing. III-1 & V-61.

Monahan, E. C., G. T. Kaye, and E. D. Michelena. 1973. Drogue Measurements of the circulation in Grand Traverse Bay, Lake Michigan. University of Michigan Sea Grant Technical Report No. 35. Ann Arbor, Michigan. 35 p.

9

9nded"- BIO - TEST aej nc

Chapter 6

THERMAL PLUME SURVEYS

Floyd T. Lovorn


OF LAKE MICHIGAN NEAR KEWAUNEE NUCLEAR POWER PLANT: PHYSICAL STUDIES

FOURTH ANNUAL REPORT January - December 1974

~d~iad BIO-TEST 10a-aE, SIc.

TABLE OF CONTENTS

Page

List of Figures ................................................ ii

List of Tables ................................................. iv

I. Introduction ................................................... 1

II. Field and Analytical Procedures ................................ 2

A. Monthly Thermal Plume Surveys ............................ 2

B. Dye Study ................................................. 4

C. Time-Temperature and Plume Velocity Study ................ 9

III. Results and Discussion ......................................... 11

A. Monthly Thermal Plume Surveys ............................ 11

B . D ye Study ................................................. 13

C. Time-Temperature and Plume Velocity Study ................ 22

D. Comparison of Plume Parameters ........................... 30

IV. Summary and Conclusions ...................................... 36

V. References Cited ............................................... 37

i

)mb4Aal B 1 - T E S T aloade, Ac.

LIST OF FIGURES

No. Caption Page

6.1 Schematic diagram of a time-temperature drogue ............. 10

6.2 Record of dye concentration at the intake and discharge

otf the Kewaunee Nuclear Power Plant on Lake

Michigan during the period 16 to 22 November 1974 . 14

6.3 Fractional decrease in excess temperature and dye

concentration with centerline distance for thermal

plumes at Kewaunee Nuclear Power Plant on Lake

Michigan, 16 to 18 November 1974 ......................... 16

6.4 Fractional decrease in excess temperature and dye

concentration with centerline distance for thermal

plumes at Kewaunee Nuclear Power Plant on Lake

Michigan, 19 to 22 November 1974 ......................... 17

6.5 Variation of surface area with excess temperature and

the equivalent dye concentration for plumes survey

ed at the Kewaunee Nuclear Power Plant on Lake

Michigan, 16 to 22 November 1974 ........................ 18

6.6 Time-temperature profiles for the thermal plume at

Kewaunee Nuclear Power Plant on Lake Michigan,

15 November 1974 ........................................ 23

6.7 Trajectories of the drogues used to obtain time

temperature data for the thermal plume at

Kewaunee Nuclear Power Plant on Lake

Michigan, 15 November 1974 .............................. 24

6.8 Time-temperature profiles for the thermal plume at

Kewaunee Nuclear Power Plant on Lake Michigan,

22 November 1974 ........................................ 25

6.9 Trajectories of the drogues used to obtain time

temperature data for the thermal plume at

Kewaunee Nuclear Power Plant on Lake

Michigan, 22 November 1974 .............................. 26

ii

daal BIO - TEST

LIST OF FIGURES (continued)

No. Caption Page

6.10 - Trajectories of the drogues used to obtain velocity

data for the thermal plume at Kewaunee Nuclear

Power Plant on Lake Michigan, 22 November 1974 29

6.11 A comparison of excess temperature areas and the areas of equivalent dye concentration for plumes

surveyed at Kewaunee Nuclear Power Plant on Lake Michigan, 17 to 22 November 1974....... . . ..31

6.12 Excess temperature versus surface area for thermal

plumes surveyed at Kewaunee Nuclear Power Plant on Lake Michigan, June-November 1974...... . ..33

6.13 Vertical variation of excess temperature for thermal plumes surveyed at Kewaunee Nuclear Power Plant

on Lake Michigan, 16 to 22 November 1974..... .. 34

iii

LIST OF TABLES

No. Caption Pag E

6.1 Summary of equipment used during a study of the thermal plume by dye tracer techniques at Kewaunee Nuclear Power Plant on Lake Michigan...... . . . . 5

6.2 Drogue speeds measured during the time-temperature study of the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan, 15 and 22 November 1974 ....... ................... 27

6.3 Drogue speeds measured for a study of the velocities within a thermal plume at the Kewaunee Nuclear Power Plant on Lake Michigan, 22 November 1974 . . . 28

iv

Sudazi BIO - T E ST Anow c

dadud BIO -TEST Ja,4alaw, Ja

Chapter 6

THERMAL PLUME SURVEYS

Floyd T. Lovorn

I. Introduction

The Kewaunee Nuclear Power Plant (KNPP) became operational in June

1974. As a result of the heated discharge from the Plant's once-through cooling

system, a thermal plume was created which altered the normal temperature

regime of Lake Michigan in the vicinity of the Plant. In order to assist in

evaluating the environmental impact of the heated discharge, surveys of the

thermal plume were conducted using both temperature measurement and dye

tracer techniques. The objectives of these surveys were:

1. to determine the horizontal and vertical extent of the thermal plume

concurrently with biological and chemical sampling in the same area;

2. to determine the centerline distance to selected isotherms;

3. to determine the maximum width of selected isotherms;

4. to determine the surface area within selected isotherms;

5. to determine the half-depth of the plume;

6. to describe other plume parameters and correlations as appropriate;

7. to separately evaluate the contributions of mixing and direct heat

transfer to the atmosphere with respect to reducing the surface area of .the

plume;

8. to provide input and comparison data for the KNPP thermal plume model.

1

S9"dediwal BIO - TEST .alenatie 4 , Inc.

I. Field and Analytical Procedures

A. Monthly Thermal Plume Surveys

Thermal plume surveys were conducted at KNPP in June, July, October

and November 1974. Only ambient temperature profiles were measured in August

and September because the Plant was not operating. During each survey, a

boat equipped with navigation and temperature measuring systems traversed the

study area on several transects in order to define ambient water temperature and

the surface extent of the thermal plume. The navigation system was a Motorola

Mini-Ranger accurate to + 10 feet at 20 nautical miles and the temperature measur

ing system was accurate to + 0.05 C. The temperature sensor was securely

mounted at 0.5 meters depth and, while the survey boat was underway, tempera

ture and position were digitally recorded at approximately one second intervals.

Following the survey of the surface plume, vertical temperature

profiles were measured at locations within and outside of the plume. At each

location, position was recorded and temperature was measured at I m depth

intervals.

Currents in the study area were continuously monitored with ENDECO

Model 105 recording current meters. Temperatures in the study area were

continuously monitored with ENDECO Model 109 recording thermographs. Con

tinuous wind speed and direction and air temperature were recorded by an MRI

Mechanical Weather Station which was located on shore approximately 75 ft

above water level. Auxiliary meteorological data were recorded periodically

on the survey boat. Details of the meteorological, and continuous current and

temperature monitgring program are discussed in Chapter 4 (Physical Studies).

2

Adma 10 BIO- TEST 2aAcoadsej, qnc.

For analysis of the thermal plume data, position and surface temperature

data were plotted with the assistance of a Cal-Comp plotter and digital computer.

Isotherms were contoured by hand at 1 C intervals. Vertical temperature profiles

were also plotted and contoured in 1 C intervals. Mean wind and current speeds

and direction were calculated for the hours during the thermal plume surveys.

The area within each contoured isotherm was measured with a plani

meter. The centerline was traced as smooth curve from the discharge outlet

through the maximum extent of each isotherm. The centerline distance to each

isotherm was measured and the maximum width perpendicular to the centerline

was measured. From the vertical temperature section nearest the centerline,

the half-depth of the plume was determined as the average depth at which

the excess temperature at the surface decreased to one half its value. However,

in order to determine the excess temperature at the surface, the ambient temp

erature had to be specified. This was done by subjective analysis of the

temperature profile upstream of the plume, the temperature profiles near the

boundary of the plume, and the thermograph and current meter records. Once

the ambient temperature was specified, the excess temperature of each contoured

isotherm within the plume was determined by subtracting the ambient temperature

from the measured temperature.

All measured parameters were tabulated and the area and centerline

distance of each isotherm was plotted versus the temperature concentration,

AT/ ATo, where AT = excess temperature of each isotherm and ATo = excess

temperature at the discharge outlet.

3

A)dadi2' BIO - TEST A/a e ae,, Anc.

B. Dye Study

A dye tracer technique was used in an intensive study of the thermal

. plume at KNPP during the period 14 to 22 November 1974. This technique

consisted of injecting a fluorescent dye (Rhodamine WT) into the condenser cooling

water flow prior to its discharge into the receiving waters and then measuring the

subsequent horizontal and vertical distribution of the dye in the receiving waters

by a fluorescent assay. Aside from cooling by direct transfer of heat to the

atomosphere, both excess heat and dye are subject to the same physical processes

of advection and turbulent diffusion. Therefore, determination of the field of

dye concentration is, after proper scaling, an estimate of the field of excess

temperature due to the heated discharge mixing with ambient water. Such an

estimate is necessary in order to separately evaluate the contribution of mixing

and the contribution of atmospheric cooling to reducing the surface area of the

thermal plume. Dye tracer techniques have been documented and used extensive

ly by other investigators (Carter 1974, U. S. Geological Survey 1968).

All equipment used in the dye study along with purpose, location and

accuracy are listed in Table 6.1. This equipment was calibrated prior to field

use. The Mini-Ranger is a precision instrument with stable electronic components

and, therefore, was calibrated only a the beginning of the study. It was field

tested daily at a reference location and each time it was within its rated accuracy.

4

Table 6. 1 Summary of equipment used during a study of the thermal plume by dye tracer techniques at Kewaunee Nuclear Power Plant on Lake Michigan.

Equipment Manufacturer Location Purpose Specifications

Digital Clock Nationwide Electronic One on each Boat Provide Accurate Resolves: Hrs. Miin., and Sec. DC 1205 Systems, Inc. Time Reference

Digital Printer Anadex Instruments, Inc. One on each Boat Record Data from Print Rate = I print/sec. DP-650 A-21 Survey Instruments

Digital Temperature and M & F Engineering One on each Boat Accurately Measure Temperature Resolution: Temperature = 0.01'C F~uorescence and Convert Fluorometer Output Fluorescence = 1% from Analog to Digital Accuracy: Temperature = 0.05'C

Fluid Metering Pump Fluid Metering, Inc. One in Plant Provide Steady and Accurate Rate Rate: 0.0 to 40. ml/min. at 30 psig RRP 0150 of Dye Injection

Fluorometer G. K. Turner Associates One on each Boat and Measure Fluorescence Sensitivity = 0.01 ppb Model I11 one in Plant Resolution = 1o of Full Scale

Mini-Ranger Motorola, Inc. One on each Boat Determine Accurate Position Accuracy * M up to range of System 20 Nautical Miles

Rustrak Temperature Gulton Industries, Inc. In Plant Record Intake and Discharge Resolution 0. 5C Recorder Model 2133 Temperatures Accuracy = 1. c

Rustrak Recorder Gulton Industries, Inc. In Plant Record Fluorometer output Resolution 1% of Full Scale Model 288

Beam Scale Douglas Horns Corp. In Plant Weigh Dye Barrel for Verification Capacity =300 lbs. 300 TP of Dye Injection Rate Resolution ounce

Water Pump Jabsco Products Survey Boat for Surface Collect Water Sample Flow Rate 5 gal/mmd. at zero 6360-0001 and Temperature head pressure

Water Pump Jabsco Products Survey Boat for Vertical Collect Water Sample Flow Rate =8 gal/mmti. at zero PAR Model 36600-0000 Dye and Temperature head pressure

0 M FT4

Adi~ai1 BIO- TEST ./alao, c.

The fluorometers were calibrated before and after the dye study. This procedure

consisted of placing a small amount of measured dye standard into a known

volume of Lake Michigan water (obtained before the start of the dye survey)

and recording the fluorescence readings on all 4 scales of the fluorometer.

Calibration curves of fluorescence versus dye concentration were then derived

for each scale by linear regression. Based on these calibrations the approximate

accuracies of the most sensitive scale were + 0.02 ppb for the in-plant fluoro

meter, + 0.03 ppb for the fluorometer used for surface plume surveys, and

+ 0.02 ppb for the fluorometer used for vertical profiles. There was some

indication that the fluorometers were slightly nonlinear for concentrations less

than 0.1 ppb. All thermistors were calibrated prior to the study. The thermis

tors used on the boats were accurate to + 0. 05 C and the thermistor used in

the Plant was accurate to + 0. 5 C.

A Turner Model 111 fluorometer was used to determine the fluorescence

of the water. Since Rhodamine WT is a fluorescent dye and fluorescence is

proportional to dye concentration, this procedure measured the distribution

of dye concentration in the water.

The fluorescence of Rhodamine WT dye is temperature dependent.

It decreases approximately 2.7% for each degree centigrade increase in temp

erature. Thus, in order to correct for this effect when calculating the dye

concentration from fluorescence; the temperature was measured simultaneously

with fluorescence.

A 20% solution of fluorescent Rhodamine WT dye with a specific

6

Ad~a;u BIO - TEST .1anaY4 ao, /c.

gravity of 1. 20 was continuously injected into the Plant's cooling water at

an average rate of 14. 1 ml/min. The uniformity of the injection rate was

ensured by using a calibrated metering pump and by periodically recording

the weight of the barrel containing the dye. The dye was injected at a

vent on the outlet side of the Plant's circulating water pump No. lB. In

jection at this point ensured that, after passage through the Plant's condensers,

the dye would be completely mixed with the cooling water.

The fluorescence of the intake water was monitored at a vent on

the outlet side of circulating water pump No. 1A and the fluorescence of

the discharge water was monitored at a vent on a 10 inch recirculating

water pipe. By switching a T-valve, water from either location passed

continuously through a fluorometer, past a thermistor and into a sump.

The outputs of the fluorometer and thermistor along with time marks were

recorded on chart paper. Intake and discharge fluorescence were monitored

alternately each hour during the surveys and, since the system was un

attended, discharge fluorescence only was monitored throughout the evening.

The first plume survey began approximately 42 hours after the

start of dye injection. This was considered to be a reasonable amount of

time for the dye to mix thoroughly with the plume and for initial transients

in the dye concentration to smooth out. Two boats were used to obtain a

synoptic survey of the temperatures and fluorescence of the plume. Each

boat was equipped with a temperature measuring system, a fluorometer

and a Motorola Mini-Ranger navigation system (Table 6.1). For the surface

7

Adukd2Ba1 BIO- TEST 2a/ahaw e, 9Ac.

plume surveys, one boat traversed the area on several transects and pumped

water from 0.5 meter depth, through a fluorometer, past a thermistor and back

over the side. The simultaneous outputs of the fluorometer, the thermistor,

a digital clock and the Mini-Ranger were digitally recorded at approximately

1 sec intervals. The second boat measured vertical profiles of fluorescence

and temperature at an average of 25 locations. These vertical. profiles were

obtained by lowering a sampling tube to a known depth and holding it

there until a stable temperature and fluorometer reading were obtained.

These readings along with time and location were digitally recorded.

Two complete plume surveys were conducted each day. Each sur

vey required 2 to 3 hours with a period of 1 to 2 hours between surveys.

Continuous current and meteorological data were also obtained

during this study. Procedures have been discussed above and in Chapter

4 (Physical Studies).

Analysis identical to that discussed above for plumes defined by only

temperature measurements was also carried out for the temperature and

dye plumes from this study. However, it was first necessary to convert

fluorescence data into dye concentrations. This was accomplished by correcting

the fluorescence to a standard temperature (20 C) and using the calibration

curves to calculate the dye concentration. In order to determine which

isopleths of dye concentration were to be contoured, the fractional decrease

in excess temperature or temperature concentration, AT/ATo, was calculated

for each isotherm. The inverse (i.e. ATo/AT) is often referred to as the

8

Ad~ia1' BIO - TEST J~aYnah , Inc.

dilution factor. The dye concentrations with dilution factors equal to those of

the isotherms were chosen to be contoured. However, the calculation of a

dilution factor also required that the background dye concentration be specified.

In every case, the background concentration was chosen to be zero. This is

equivalent to assuming that the background fluorescence remained constant

throughout the 9 day period of the study.

C. Time-Temperature and Velocity Study

Time-temperature and velocity measurements were obtained twice during

the study period (15 and 22 November) by repeatedly placing a drogue equipped

with a continuous recording temperature system (Figure 6.1) into the discharge

and tracking the resulting drogue trajectory with shorebased transits. With

this method, the time rate of change of both temperature and velocity within

the plume were determined. The temperature system was estimated to be

accurate to within 0.5 C. On 22 November, additional drogues without a

recording system were used to further define the velocity structure within

the plume. An abbreviated survey of the thermal plume was conducted before

and after each set of measurements.

The time temperature profiles were plotted and the drogue speed

and direction were tabulated. The plume configuration before and after each

set of drogue measurements was plotted along with the drogue trajectories.

9

0

MARKER FLAG

T 0 o **

WaTERPROOF E30)

(Fits into floot)

THERMISTOR

WINDOW

SHADE DROGUE

Schematic diagram of a time-temperature drogue.Figure 6.1


All figures illustrating the temperature structure of the thermal plumes

are presented in Appendices 6-A and 6-C. The data from vertical temperature

profiles are tabulated in Appendices 6-B and 6-E. All figures illustrating

the plumes defined by dye concentration are presented in Appendix 6-D.

Summaries of Plant operation data, measured values of plume characteristics,

meteorological data, and ambient temperature and current data are presented

in Appendix 6-F. More detailed data on the ambient current, temperature,

and meteorology are presented in Appendices 4-A, 4-H, and 4-I, respectively.

The excess heat discharged by the Plant as reported for each plume is based

on the temperature difference across the condensers and was derived from opera

tion data supplied by Plant personnel.

A. Monthly Thermal Plume Surveys

25 June

On 25 June, the Plant was discharging excess heat at the average rate

of 3.92 x 10 British Thermal Units/hour (BTU/hr). The thermal plume created

by this discharge was directed southward. Its offshore boundary was defined

by a large temperature gradient and a sharp reduction in turbidity from high

within the plume to low outside. The apparent effect of the promontory south

of the discharge structure was to deflect the plume to the southeast until ambient

currents turned it due south approximately 3000 ft from the discharge outlet.

Sharp horizontal and vertical temperature gradients existed near the

centerline of the plume and within 2500 ft of the discharge outlet. Near its

centerline, the plume was in contact with the lake bottom out a distance of

11

I

-9"aAial B 10 - T E S T

S)dnude4d BIO - TEST Ynawat, Ac.

approximately 1800 ft and a depth of 3.5 m.

23 July

On 23 July, the Plant was discharging excess heat at the average

rate of 3.68 x 10 9 BTU/hr. The thermal plume created by this discharge

was directed offshore and northward. The inshore boundary of the plume

was difficult to define because the plume temperature and the ambient temp

erature were 18 C to 19 C near the shore. Due to instrument malfunction,

definition of isotherms less than 21 C was not completed and no vertical

profiles were made within the plume. However, prior to the survey, vertical

profiles of ambient temperatures were measured south of the Plant. The ambient

vertical temperature structure showed that the plume was discharging into a

horizontally and vertically stratified water column. This type of structure

would tend to inhibit the vertical mixing of the plume.

23 October

On 23 October, the Plant was discharging excess heat at the average

rate of 2.20 x 109 BTU/hr. The thermal plume was irregular and the boundaries

were not as sharply defined as the southward plume in June. This was probably

a result of the ambient current changing from a northward to a southward current

before and during the plume survey; whereas, in June, the currents had been

steadily southward for several hours before the plume survey. However, as

in June, the apparent effect of the promontory was to deflect the warmest part

of the plume southeastward, away from the southern shoreline.

The thermal plume was apparently discharging into a region of upwelling.

12

dad-Bal1 BIO- TEST ./make6 , c.

This is inferred from the ambient temperature structure and wind data. The

coldest water was nearest the shore and the wind had been blowing offshore

for the previous 12 hours. This situation made the outer edge of the plume

difficult to detect since it merged with the warmer offshore water.

The plume was 6 to 7 m deep near the centerline. The increased

vertical extent of this plume compared to plumes surveyed in June and July

was probably a result of greater wind speed promoting vertical mixing in

nearly isothermal ambient temperatures.

12 November

On 12 November, the Plant was discharging excess heat at the average

rate of 2.01 x 109 BTU/hr. The thermal plume was directed offshore in response

to the wind and local current.

The ambient temperature was nearly isothermal at 8.8 C. Plume

temperatures greater than 0.5 C above ambient made contact with Lake bottom

out to a distance of 2500 ft and a depth of 6 m. The increased vertical extent

of this plume compared to plumes surveyed in June and July was probably a

result of greater wind speed promoting vertical mixing in nearly isothermal

conditions. This also contributed to reducing the surface extent of the plume

since the excess heat of the plume was distributed over a greater volume of

water in the vertical.

B. Dye Study

A record of the intake and discharge dye concentrations throughout

the study period is presented in Figure 6.2. The centerline distances for each

13

0

DISCHARGE

DYE TURNED OFF

[14I~O

0.0

.

0.0

iv' IA!

C..

Is ~

11111 111111 titlE InlEt iii pill II 'Lull 111.1.

1B 19 20 21

'.

NOVEMBER 1974

Record of dye concentration at the intake and discharge of the Kewaunee Nuclear Power Plant on Lake Michigan during the period 16 to 22 November 1974.

0

-4

0 "'

11111mg.. It, -22

it Iu

L.L..LLLAA I III I I I

INTAKE

0

-I-

'o

Figure 6.2

IAAAAssesI r

9/n1 izz B10- T E ST Ytaiei, 4C

temperature and dye plume are plotted in Figures 6. 3 and 6.4, and the surface

areas are plotted in Figure 6.5.

16 November


rate of 1.96 x 10 BTU/hr. The thermal plume created by this discharge was

directed offshore. Two surface temperature plumes and two vertical dye and

temperature plumes were surveyed. However, a fluorometer malfunction pre

cluded a survey of the surface dye plume.

The rapid centerline temperature decay and smaller surface areas

of the afternoon plume compared to the morning plume were probably a result

of increased vertical mixing in the afternoon. This was indicated by a

significant increase in the half-depth from the morning to the afternoon

plume.

The increased vertical mixing in the afternoon coincided with and

was probably a result of an increase in ambient current speed. Recirculation

into the Plant's intake due to the increased depth of the plume was inferred

from a rapid rise in the dye concentration at the intake.

17 November


rate of 1.94 x 109 BTU/hr. The two plumes surveyed on this date were north

eastward. In response to increasing current speed during the two surveys,

(0.19 fps to 0.32 fps), the afternoon plume was closer to shore than thelmorn

ing plume. In comparison with the local bathymetry (Chapter 2, Physical Studies),

15

Adad~ad BIO -TEST waea, Ac.

MORNING AFTERNOON O Temperature A Temperature * Dye ADye

16 November A

A

I I I I I ~

20 40 60 80

17 November

I I IOf

20 40 60

- 0

18 November - A

I I II IIII

0 40 6 FEET (102)

CENTERLINE DISTANCE

0

80

80

Figure 6.3 Fractional decrease in excess temperature and dye concentration

with centerline distance for thermal plumes at Kewaunee Nuclear

Power Plant on Lake Michigan, 16 to 18 November 1974.

16

1.0

0

0.5

00.0

1.0

0 o

<0.5

- A - @0

@0

A

00.0

1.0

0

<0.5

0.0 O0

I I I I I I I I

2

Adadual BIO - TEST .1 aa i ,2c.

MORNING AFTERNOON o Temperature ATemperature *Dye ADye

19 November

A

I I I I I I I I

20 40 60

20 November

20 40 60

22 November

.5%

C.

'3

a a a a a ft

20 40 60

FEET (0 -) CENTERLINE DISTANCE

Figure 6.4 Fractional decrease in excess temperature and dye concentration with centerline distance for thermal plumes at Kewaunee Nuclear Power Plant on Lake Michigan, 19 to 22 November 1974.

17

1.0

0

CL50

'I I'1

0 800.0

1.0

O

<]0.5

0.0

1.0

0

'10.5

0.0

0

0 so

16 November

0

0

0

0

17 November

00

00

0

.5 I .05 .1 .5 I

18 November

A

*0

0

.5 AT/A To

19 November

0\ 0

0

0,

AO

.5 1

20 November

8

.5 I

22 November

\0

.5 I

Figure 6.5 Variation of surface area with excess temperature and the equivalent dye concentration for plumes surveyed at the Kewaunee Nuclear Power Plant on Lake Michigan, 16 to 22 November 1974. The excess temperature and equivalent dye concentration are expressed as a fraction, AT/ATo, of the excess temperature or dye concentration at the discharge outlet.

0

1000

4

4J OD

Cr

0

100

10

0

-4

.1

)dadal BIO - TEST .Y a In.

the centerline of the morning plume extended northeastward between the 25 ft and

30 ft depth contours. The afternoon plume was closer to shore with its center

line between the 20 ft and 25 ft contours. There was little difference between

the dye or temperature surface area of the two plumes or between the dye and

temperature surface area of the same plume. This was also true of the center

line distance. The mean half-depth of the two temperature plumes were equal.

There was some recirculation in the morning, probably as a result of the plume

moving over the intake and closer to shore.

18 November


rate of 1.97 x 10 BTU/hr. The two plumes surveyed on this date were

noticeably different from one another. The afternoon plume was smaller and

deeper than the morning plume. This was probably a result of the unsteady

ambient current conditions which prevailed before and during the surveys.

The ambient current had been northward for the previous 19 hours and de

creasing from 0.32 fps to 0.10 fps, reaching a minimum during the morning

survey. Both wind speed and current speed increased in the afternoon to 10

mph and 0.14 fps, respectively. This promoted vertical mixing and increased the

depth of the afternoon plume compared to the morning plume. Smaller dye and temp

erature surface areas and a more rapid centerline decay of dye and temperature

were a result. There was also a difference between the dye and temperature

plume in the morning. This may have been a result of a large decrease in re

circulation for 6 hours previous to the morning survey and a rapid increase

19

A9Hdadtu' BIO - TEST _Zaaa, c.

in recirculation as the plume moved northward in the afternoon. Under such

conditions, a more synoptic method of survey is required in order to adequately

define the plume. Due to the variety and magnitude of changing conditions

prior to and during the surveys, these plumes could not be considered as

representative of steady state plumes.

19 November


rate of 1.95 x 10 BTU/hr. The two plumes surveyed on this date were nearer

the shoreline than any other plumes surveyed during the study. The center

line of the morning plume extended northeast between the 20 ft and 24 ft depth

contour, and the centerline of the afternoon plume was between the 16 ft and

20 ft contours. The ambient current was steady and northward at approximately

0.20 fps for 11 hours prior to the surveys. The wind was also steady from the

southeast at 9 to 14 mph for the previous 11 hours. A small increase in mean

current speed to 0.24 fps forced the afternoon plume closer to the shoreline.

There was very little difference between the dye or temperature

surface areas for the same plume or between the two plumes. This was also

true for the centerline distance. Except for an increase in recirculation, these

two plumes could be considered very near steady state for the prevailing ambient

conditions.

The afternoon survey presented an example of the ability of the dye tech

nique to define the plume when temperature measurements alone could not separate

the plume from ambient conditions. That is, the 1 C excess temperature isotherm

20

d i BIO-TEST 10 -e TSw, Inc.

(7 C absolute) was not distinguishable by temperature measurements alone from

background temperatures at 7 C but the equivalent dye concentration (0.26 ppb)

did define the 1 C excess temperature isotherm.

20 November


rate of 1.91 x 109 BTU/hr. The two plumes surveyed on 20 November were the

only southward plumes of the study. Approximately 3 hours prior to the morn

ing survey the current changed from a northward to a southward current and

the speed increased from 0.07 fps to 0.21 fps in the morning and 0.24 fps in

the afternoon. The wind was from the southwest, off the land, at 12 mph to 20

mph. No vertical profiles were measured for either plume.

There was very little difference in the dye and temperature centerline

distance between the two plumes. However, the surface areas decreased slightly

from the morning to the afternoon plume. Based on previous plumes, this was

probably a result of increased vertical mixing due to increasing ambient current

speed. There was no evidence of recirculation. This was to be expected with

a southward plume.

22 November


rate of 1.94 x 10 BTU/hr. Only one plume was surveyed on this date. The

ambient current was northward and increasing rapidly in speed from 0.07 fps

at 2 hours prior to the survey, to 0.38 fps by the end of the survey. The

21

t~Adadu BIO - TEST a ,

discharge dye concentration also changed rapidly as recirculation occurred

between 0800 and 1000 hours. There was little difference in areas and center

line distance between the dye and temperature plume. Due to the rapidly

changing ambient conditions, this cannot be considered a steady state plume.

C. Time-Temperature and Plume Velocity Study

Time-temperature profiles simulate the temperature history that an

organism would experience if it was entrained at the intake and then discharged

with the cooling water. The profiles for the KNPP thermal plume (Figure 6.6

and 6.8) show that within 15 minutes and 1200 ft of the discharge outlet (Figures

6.7 and 6.9), the excess temperature to which the organism would be subjected

decreases by 50%. On 15 November, temperatures approximately 0.5 C above

ambient were reached within an hour after the drogue was released. Shorter

runs were necessary on 22 November and ambient was not reached because the

drogues were moving onshore and grounding. The more rapid decrease in

temperature on 22 November compared to 15 November may have been due to

the drogue moving out of the plume as the plume changed rapidly from offshore

to alongshore.

Based on volume discharge rate and cross sectional area, the discharge

velocity at the outlet was 5 fps. The drogues were released approximately 100 ft

from the discharge outlet and their initial speeds show that the discharge velocity

decreased by 50% within 150 ft of the outlet (Tables 6.2 and 6.3). After 15 minutes

and within 1200 ft of the discharge outlet (Figures 6.7, 6.9 and 6.10), the drogue

22

Run #1 Run #2 iA

A A

00

A

0

I I I I I I I I I I _ ._ I I I I I I I

0 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51

TIME IN MINUTES

Figure 6.6

54 57 60

Time-temperature profiles for the thermal plume at Kewaunee Nuclear

Power Plant on Lake Michigan, 15 November 1974.

0

13

12

A

A

II

I0

C) 0.

w

I-

0

O

9

8

7 a I

Ad 1a 0 BIO- TEST 2a~ma&u", Ac.

Figure 6.7

24

Trajectories of the drogues used to obtain time-temperature data for the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan, 15 November 1974.

Run *I *

Run # 2 -A

***

0 3 6 9 12 15

Figure 6.8

18 21 24 27 30 33 36 39 42 45 48 51 TIME IN MINUTES

Time-temperature profiles for the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan, 22 November 1974.

0

13

12

U'

0

0j

11

10

9

8

7

a

ndad"wal BIO - TEST ),c.

Figure 6.9

26

Trajectories of the drogues used to obtain time-temperature

data for the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan, 22 November 1974.

%badzdial BIO - TEST .laboauwi, Inc.

Table 6.2 Drogue speeds measured during the time-temperature study of the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan, November 1974.

Elapsed Drogue Speed (ft/sec) Time 15 November 22 November

(Minutes) #1 #2 #1 #2

0. 0 Initial Placement Initial Placement 0.5 2.8 2.6 1.7 2.3 1.0 2.8 2.3 1.7 1.5 1.8 1.6 1.6 2.3 2.0 2.3 1.9 1.8 1.1 2.5 -a 1.4 1.5 1.7 3.0 1.4 1.8 1.6 0.7 3.5 1.6 1.3 1.5 0.8 4.0 1.2 1.4 1.7 0.8 4.5 1.8 2.1 1.3 0.8 5.0 1.1 1.0 1.3 0.6 6.0 1.0 1.3 1.0 0.9 7.0 1.1 1.3 1.0 0.8

8.0 - 0.9 0.8 1.0 9.0 0.8 1.0 0.6 1.2

10.0 0.7 0.9 0.9 1.2 11.0 0.8 1.5 0.6 0.9 12.0 1.1 0.3 1.0 0.5 13.0 0.7 0.5 0.7 0.5 14.0 0.8 0.6 0.7 0.6 15.0 0.7 0.5 0.8 1.3 31.0 - - - 0. 3 b 41.0 - - 0.7b 45.0 0.7b 55.0 - 0.5b

a - = Not measured. b Picked up drogue.

27

AdYia BIO - TEST ./aaa ac.

Table 6.3 Drogue speeds measured for a study of the velocities within a thermal plume at the Kewaunee Nuclear Power Plant on Lake Michigan, 22 November 1974.

Elapsed Time Drogue Speed (ft/sec)

(Minutes) #1 #2 #3 #4

0. 0 Initial Placement 0.5 -a 1.0 1.0 0.7 1.0 1.2 1.5 1.2 0.1 1.5 2.3 1.8 a 0.3 2.0 2.0 1.8 1.2 2.5 1.3 2.0 4.2 3.0 1.5 2.2 1.4 1.0 3.5 1.1 1.9 1.6 1.6

4.0 1.0 3.4 3.8 1.6 4.5 1.0 6.4 1.8 5.0 1.0 0.9 1.5 2.6 6.0 1.3 0.6 1.8 7.0 1.2 0.6 1.3 0.8 8.0 1.6 0.6 1.0 0.5 9.0 0.9 0.7 0.8 0.6

10.0 0.7 0.7 1.0 0.2

11.0 1.0 0.6 0.4 0.0 12.0 1.0 0.5 0.5 0.1 13.0 0.8 0.5 0.5 0.1 14.0 0.7 0.3 0.6 0.1 15.0 1.3 0.2 0.6 0.1 40.0 - - 0.6b 52.0 - - 0.2

102.0 - 0.4b 113.0 0.4b

a b

- = Not measured.

Picked up drogue.

28

Figure 6.10 Trajectories of the drogues used to obtain velocity data for the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan, 22 November 1974.

29

Adaual BIO - T ES .5 Tc

speeds were reasonably constant. However, the speed of the drogues at this

point was greater than the ambient current speed recorded by current meters.

This indicates that after approximately 15 minutes the drogues may have been

significantly affected by the wind which was blowing at 21 mph on 15 November

and 13 mph on 22 November.

D. Comparison of Plume Parameters

The areas within isotherms and within the equivalent isopleths of dye

concentration are compared in Figure 6.11. Points which fall on the diagonal

indicate equal areas. If surface cooling had a significant effect on reducing

the surface area of the thermal plume, the points would consistently fall below

the diagonal because the dye plume would be larger than the temperature plume.

The figure reveals approximately an equal scatter of points on both sides of the

diagonal. The scatter is largest for small areas and was most likely due to the

difficulty of defining small areas in regions of high gradients of temperature

and dye concentration. These data infer that, there was little difference

between the area of the dye plumes and the area of the temperature plumes. A

similar result was obtained by a comparison of centerline distances and a com

parison of maximum widths. These results imply that the size and configur

ation of the thermal plume was primarily a result of mixing with ambient water.

The surface areas were apparently too small for direct heat transfer to the

atmosphere to have a measurable effect on reducing the surface area of the

plume.

30

Sndd-B BIO - T E ST .2abat&e4, Acx.

100010 100 DYE ISOPLETH AREA (ACRES)

Figure 6.11 A comparison of excess temperature areas and the areas of equivalent

dye concentration for plumes surveyed at Kewaunee Nuclear Power

Plant on Lake Michigan, 17 to 22 November 1974.

31

1000

U)

Ui

C-,

0i W:

100

I0

-9wail BIO0 - T E ST 2aMaa4, Ac

II

ndadi-u BIO - TEST .al t, )nc.

the surface area of the plume .

All isotherm areas versus AT/ATo have been plotted in Figure 6.12 and

a smooth curve visually fitted to the data. There is considerable scatter but

the smooth curve clearly illustrates the trend of the data. The sources of

scatter among the data points include:

1. Plume-to-plume variation in ambient diffusivity, ambient velocity and

plume depth;

2. Inaccurate areas in those regions of small excess temperature

where ambient temperature variations and plume meandering can produce

significant errors;

3. Inadequacy of choosing a single ambient temperature.

Similar results were reported by Asbury and Frigo (1971) in their attempt to

develop a phenomenological model for predicting thermal plume areas. Additional

data plus selective analysis of only those plumes which are considered to be

steady state may help reduce the scatter.

Excess temperature versus depth from the November plume data were

plotted in an attempt to define the mean profile for vertical variation of excess

temperature (Figure 6.13). The temperature profiles were chosen from the same

stations near the centerline at which the half-depth had been determined. The

mean curve was visually estimated as a best fit to the data.

The curve indicates that, on the average, the excess temperature at

the surface was reduced by 10% at 1 m depth and by 50% at a depth of 3 m.

However, due to the considerable scatter in the data, the mean curve can only

32

b z

aa x_ z a b

Ac 0

a

I

c Y z

A@b K

c

MORNING AFTERNOON 0 16 Nov 0 16 Nov A 17 Nov A 17 Nov E 18 Nov ; l8 Nov a 19 Nov © 9 Nov b 20 Nov ( 20 Nov c 22 Nov x 25 Jun Y 23 Jul z 23 Oct 12 Nov

1 I I I I l l l

ID0I I I ! i i ! i j I I I I I I l I

10

ISOTHERM AREA (ACRES)

I I I I I liii

102

Figure 6.12 Excess temperature versus surface area for thermal plumes surveyed at Kewaunee Nuclear Power Plant on Lake Michigan, June-November 1974.

0

1.0

0

< CI

0

0

*

0

-4

.0 1L 0.1

A

i I I I I I I I I

z

ndd-ad BIO - TEST AaedZc.

AT/ ATs0.6 0.8

0 * 0 0 *

0 0

2

q

w

.r

0

. a

0

0 0

Figure 6.13 Vertical variation of excess temperature for thermal plumes surveyed at Kewaunee Nuclear Power Plant on Lake Michigan, 16 to 22 November 1974.

34

0.2 0.4

* **

0 0

0 00

0 0e 0

m 0

*

10

0

W

* a

0

A#u~dBad1 BIO- TEST Ja-a ,wIc.

ke considered as indicative of the vertical variation of excess temperatures

and, perhaps, as a guide in planning environmental sampling strategies related

to the thermal plume.

35

tSm/ ia BIO - TEST aacu4, Ac.


1. Four thermal plumes were surveyed concurrently with biological

and chemical sampling in the same area.

2. An intensive study of eleven plumes was successfully conducted using

dye tracer techniques.

3. Characteristics of each plume such as centerline distance, maximum

width, surface area, and half-depth were measured and tabulated. These

data will provide input and comparisons for the KNPP thermal plume model.

4. Mixing with ambient water was the dominant factor in reducing the

size of the thermal plume when AT/ATo was greater than 0.1 and the Plant was

operating near 50% power.

5. Direct heat transfer to the atmosphere did not make a measurable

contribution to reducing the size of the thermal plume when AT/ATo was greater

than 0.1 and the Plant was operating near 50% power.

6. The mean half-depth of the plumes measured in November was 3.5

meters.

7. Time-temperature profiles indicated that an organism present in the

discharge from the Plant would experience a 50% decrease in excess temperature

within 15 minutes and 1200 ft from the discharge outlet.

8. The discharge velocity decreased by 50% within 150 ft of the discharge

outlet.

36

Sndud-wal BIO - TEST 2abmaeraw, Ac.

V. References Cited

Asbury, J. G. and A. A. Frigo. 1971. A phenomenological relationship for

predicting the surface areas of thermal plumes in lakes. ANL/ES-5. Argonne National Laboratory, Argonne Illinois. 20 p.

Carter, Harry H. 1974. The measurement of Rhodamine tracers in natural sys

tems by fluorescence. IN the physical processes responsible for the dis

persal of pollutants in the sea with special reference to the nearshore

zone. (eds. G. Kullenberg and J. Talbot) published by: International

Council for Exploration of the Sea. Arhus, Denmark. 13 p.

U.S. Geological Survey. 1968. Fluorometric procedures for dye tracing.

IN Techniques of water-resource investigations of the United States

Geological Survey. U.S. Dept. of Interior

C

37

cduala1 BIO - TEST Aabues,9Ac.

Chapter 7

THERMAL PLUME MODEL

Floyd T. Lovorn


PHYSICAL STUDIES


9au-al BIO - TEST 2aAlatow, Pc.

TABLE OF CONTENTS

Page

List of Figures. . ............. . . . ..

I. Introduction.. ............ . . . ..1

II. Field and Analytical Procedures........ . . . . 2

III. Results and Discussion............. . . . . . 3

A. Half-Depth ............................. 3 B. Centerline Distance . . . . . . .. . . . . . . o. 4 C. Maximum Width .. . . . . . . . 7 D. Area . . . ........ ....... 9

E. Refinements of the Model . ... .. . . . 11

IV. Summary and Conclusions. ........ . . . .. 12

V. References Cited................ . . . 13

i

da~d~al BIO - TEST aac.

LIST OF FIGURES

No. Caption Page

7.1 A comparison of predicted and measured values of the

half-depth of the thermal plume at Kewaunee Nuclear

Power Plant on Lake Michigan ................................. 5

7.2 A comparison of predicted and measured values of the

centerline distance of the thermal plume at Kewaunee

Nuclear Power Plant on Lake Michigan ......................... 6

7.3 A comparison of the predicted and measured values of

the maximum width of the thermal plume at Kewaunee

Nuclear Power Plant on Lake Michigan .................. 8......8

7.4 A comparison of the predicted and measured values of

the surface area of the thermal plume at Kewaunee

Nuclear Power Plant on Lake Michigan ......................... 10

ii

ctual~1 BIO- TEST 1, Ac.

Chapter 7

THERMAL PLUME MODEL

Floyd T. Lovorn

I. Introduction

In 1973, Industrial BIO-TEST Laboratories, Inc. formulated a predictive

model to describe the thermal plume at the Kewaunee Nuclear Power Plant

(KNPP). The basis of the model was developed by Pritchard (1973). Data

on the thermal plume at KNPP was collected in 1974 and predictions of the

model have been compared with this data. The objective of this comparison

was to determine how well the predicted values of half-depth, centerline dis

tance, width, and area of the thermal plume fit the measured values of these

parameters.

1

S9dediwd BIO - TEST .1a4aakew, Ac.


Input and comparison data for the thermal plume model have been developed

from an extensive field study of the KNPP thermal plume. Part of this field

study was conducted in November 1974 by means of dye tracer techniques

(Chapter 6, Physical Studies). Aside from cooling by direct transfer of heat to

the atmosphere, both excess heat and dye are subject to the same physical

processes of advection and turbulent diffusion. Thus, the distribution of dye

concentration simulated the thermal plume which would have occurred if mixing

with ambient water were the only mechanism for reducing the excess temperature

of the thermal plume.

An important result of the dye study was that, within specified limits of

excess temperature and Plant power production, direct transfer of heat to the

atmosphere did not have a measurable effect on reducing the size of the plume.

Based on this result, only mixing was considered in the model predictions for

half-depth, centerline distance, maximum width, and area. Therefore, predicted

values of these parameters for selected isotherms of excess temperature have been

compared to the measured values as determined from the plumes of dye concen

tration.

2


The input data to the model and the calculated values of half-depth,

centerline distance, width, and area for selected isotherms are tabulated

in Appendix 7-A. The measured values for isopleths of dye concentration

are tabulated in Appendix 6-F. Details of the KNPP thermal plume model

are discussed in Industrial BIO-TEST Laboratories, Inc. (1973).

A. Half-Depth

The half-depth of the thermal plume is defined as that depth at which

the excess temperature at the surface decreases to one half its value. For this

model, the half-depth is primarily a function of the dimensions of the discharge

outlet and the initial densimetric Fronde number. The specific relationship is,

H1/ 2 = 0.3/ (Ar) /4 (Fo) 3/4

where H,1/ 2 = half-depth, H = vertical dimensions of the discharge outlet,

Bo = width of discharge outlet, Ar = Ho/Bo, and Fo = the initial densimetric

Froude number. The densimetric Froude number is the square root of the

ratio of the horizontal inertial forces associated with the excess momentum

in the high velocity or jet region of the plume to the buoyancy forces in

the jet region. That is,

F 0 U2/gHo (AP /P)O

where U2 = velocity at the discharge outlet, g = acceleration of gravity

(32.2 ft/sec2), (Ap/p)o = fractional change in the density of the heated

water compared to ambient water, and the subscript "o" designates the

values of these quantities at the discharge outlet. An increase in F implies

3

fedewa BIO - T E ST .&2aaw , Inc.

an increase in the ability of the plume to entrain and mix with the ambient

water.

In Figure 7.1, the predicted half-depths of the plumes have been

compared with the measured half-depths. If points fall on the diagonal in

the figure, then the predicted and measured values are equal. All points

in Figure 7.1 are above the diagonal which implies that the model predicts

larger half-depths than are actually measured. The predicted values are

too large by a factor of two. However, the range of variation of both pre

dicted and measured values of half-depth is approximately equal.

B. Centerline Distance

The centerline distance is the distance measured along the center

line of the plume to a selected isotherm. The model predictions are based

on the relationship,

CL = n(AT/ATo)-b

where CL = centerline distance to AT, AT/ATo is the ratio of excess temper

ature at a selected isotherm to the initial excess temperature at the discharge

outlet, and n and b depend on environmental and discharge parameters such

as Froude number, distance from discharge outlet, and dimensions of the

discharge outlet.

In Figure 7.2, the predicted centerline distances have been compared

to the measured distances. For measured values of the centerline distance,

CL, less than approximately 3000 ft, the predicted values are within a factor

of two of the measured values. However, for measured values of CL greater

4

A9dd- Ba BIO - T E ST A/ated ,Ac

A

0 0

0

a

2 4 (METERS)

MEASURED HALF-DEPTH

Figure 7.1 A comparison of predicted and measured values of the half-depth of the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan..

5

7

I

4 CL LI

X:A

2a-

MORNING AFTERNOON

x - 25 Jun

z - 23 Oct

0 - 12 Nov

o - 16 Nov - *

A - 17 Nov - A

E - 18 Nov - a

a - 19 Nov - ©

OK 0 6 8

S W~~ BIO - T E S T ./elw c

Fv

U

s

A

V

VV A, 0 @ b

a b

a

I I I I I I l I

MEASURED CENTERLINE DISTANCE (FEET)

Figure 7.2 A comparison of predicted and measured values of the

centerline distance of the thermal plume at Kewaunee

Nuclear Power Plant on Lake Michigan.

6

MORNING AFTERNOON

A - 17 Nov - A

o - I8 Nov - 0

a - 19 Nov - @

b - 20 Nov

V - 22 Nov

105

I

LU z

U,

z

I

z

U

C-)

a-

10 2 V1O2

I I I I I II II I I I I III

Adad 1alBI - T E ST .1bola , c.

Adadial BIO - TEST 1a4a64e, ..

than 3000 ft the predicted values are as large as 8 times the measured value.

This sudden increase in the error of the predicted values of CL occurs for

those isotherms such that AT/ATo is less than or equal to 0.2. In the model,

this value of AT/ATo corresponds to a transition from mixing by mechanical

stirring and turbulence generated by the momentum of the plume to that mixing

which depends on the intensity of the natural turbulence of the ambient water.

Therefore, the results imply that the mixing for AT/ATo greater than 0.2 is

more intense than has been accounted for in the model.

C. Maximum Width

The maximum width of an isotherm is defined as the greatest distance

across an isotherm and is measured perpendicular to the centerline. The model

predictions are based on the relationship,

W = Bo + m CL

where W = maximum width of the excess temperature isotherm AT, Bo = width

of discharge outlet, CL = centerline distance to the excess temperature isotherm

AT, and m is a parameter which depends on environmental and discharge

parameters.

In Figure 7.3, the predicted maximum widths have been compared to

the measured maximum widths. For measured values of the maximum width,

W, less than 1000 ft, the predicted values are within a factor of 1.7 times the

measured values. When the measured value of W exceeds 1000 ft, the predicted

values become as large as 2.5 times the measured values. As might be ex

pected, since W is primarily a function of CL, this sudden increase in the error

7

SdzdBa1 BIO- TEST 2a,a1 ,c

0

a

0,

b

a 0

: @b

I I I I I I I I I I I I I I I1

102

MEASURED WIDTH

104103

(FEET)

Figure 7.3 A comparison of the predicted and measured values of

the maximum width of the thermal plume at Kewaunee

Nuclear Power Plant on Lake Michigan.

8

104

MORNING AFTERNOON

A - 17 Nov - A a - 18 Nov - a

a - 19 Nov - @

b - 20 Nov- V - 22 Nov

V

I03

a 0

b /Z

A

I W

I0

0

10I0

IO2

Adad2Ba BIO- TEST .2aoawe,)c.

of the predicted values of W occurs for those isotherms such that AT/ATo is

less than or equal to 0.2.

D. Area

The area of an isotherm or isopleth of dye concentration is directly

related to its centerline distance and width. For this model, the relationship

between area, centerline distance and width of an isotherm is

Area = 0.86 CL W

This area is uncorrected for cooling by direct transfer of heat to the atmos

phere.

In Figure 7.4, the predicted values of the uncorrected areas have

been compared to the measured values as determined from the area within

isopleths of dye concentration. Since the predicted area is a function of

centerline distance and maximum width, it is expected to reflect some of

their characteristics as discussed above. Predicted values of isotherm area

are within a factor of 3 of the measured values for areas less than 50 acres.

For areas greater than 50 acres, the predicted area can be too large by a

factor of 20.

The comparison of predicted and measured values for thermal plumes

surveyed on 25 June and 23 July have also been included in Figure 7.4. Since

they were surveyed by temperature measurements only, the predicted values

have been corrected for surface cooling. These two plumes have been included

here because they were the only plumes surveyed with the Plant operating

near 100% power and with stratified ambient water temperature. Compared

9

BAd 0 BIO- TEST a , Ac

a

0

Vb

X

©9

A

x

A

x

a

b

El

b

10 MEASURED AREAS (ACRES)

Figure 7.4 A comparison of the predicted and measured values of the surface area of the thermal plume at Kewaunee Nuclear Power Plant on Lake Michigan.

10

I03

Va

x

E

b EAb

A

0

U

0 W a

0..

x

102

10

13

1.0

0.119 0.1

x - 25 Jun

y - 23 Jul

A - 17 Nov - A

o - 18 Nov

a - 19 Nov - a

b - 20 Nov - b

V - 22 Nov

1.0

to other plumes, the agreement between predicted and measured values for both

25 June and 23 July is very good.

E. Refinements of the model

The above results suggest some simple refinements of the model.

For example, reduce the coefficient of the half-depth by a factor of two.

Another refinement would be to increase the predicted intensity of mixing

for those excess temperature isotherms which are less than 20% of the initial

excess temperature. This would amount to reducing the exponent in equation

(3) whenever AT/ATo is less than 0.2.

These refinements are not arbitrary, as they might seem, because

the basic model was developed by statistical methods using extensive obser

vational data (Pritchard 1973). Thus, the effect of a correction factor is

to bring the predictive relationship into closer correspondence with the

particular statistics of the KNPP thermal plume. Alternatively, if sufficient

data become available, statistical correlations can be developed based on

KNPP thermal plume data alone.

11

_"aAual BIO0 - T E ST .1baedIc.

eddal BIO-TEST 1ao-to, ESc.


1. Predictions of the half-depth of the plume are too large by a factor

of two.

2. The centerline distance for those excess temperatures greater than

20% of the initial excess temperature can be predicted within a factor of two.

3. The maximum width for those excess temperatures greater than 20%

of the initial excess temperature can be predicted within a factor of 1.7.

4. The area for those excess temperatures greater than 20% of the

initial excess temperature can be predicted within a factor of three.

5. The model underestimates the amount of mixing when the excess

temperature is less than 20% of the initial excess temperature and therefore

overestimates the size of the plume at these temperatures.

12

Adeduda1 BIO-TEST .a 4a-e, TSc.

V. References Cited

Industrial BIO-TEST Laboratories, Inc. 1973. Preoperational thermal monitoring program of Lake Michigan near Kewaunee Nuclear Power Plant, January

December 1973. (IBT No. 643-03208) Report to Wisconsin Public Service Corporation, Green Bay, Wisconsin. 1275 p.

Pritchard, D. W. 1973. The fate of and effect of excess heat discharged into Lake Michigan with specific application to the condenser cooling water discharge from Zion Nuclear Power Station. Report prepared for Commonwealth Edison Company. Chicago. 72 p.

13

& b i0 -t e s t 2 p au, inc.& b i0 -t e s t 2_p au, inc. 1810 frontage road northbrook,...

Documents