U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
OLD BEN MINE RESERVOIR
FRANKLIN COUNTY
ILLINOIS
EPA REGION V
WORKING PAPER No, 311
CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
699-440
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REPORT
ON
OLD BEN MINE RESERVOIR
FRANKLIN COUNTY
ILLINOIS
EPA REGION V
WORKING PAPER No, 311
WITH THE COOPERATION OF THE
ILLINOIS ENVIRONMENTAL PROTECTION AGENCY
AND THE
ILLINOIS NATIONAL GUARD
JUNE, 1975
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1
CONTENTS
Page
Foreword ii
List of Illinois Study Lakes iv
Lake and Drainage Area Map v
Sections
I. Introduction 1
II. Conclusions 1
III. Lake and Drainage Basin Characteristics 3
IV. Lake Water Quality Summary 4
V. Nutrient Loadings 8
VI. Literature Reviewed 11
VII. Appendices 12
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11
FOREWORD
The National Eutrophication Survey was initiated in 1972 in
response to an Administration commitment to investigate the nation-
wide threat of accelerated eutrophication to fresh water lakes and
reservoirs.
OBJECTIVES
The Survey was designed to develop, in conjunction with state
environmental agencies, information on nutrient sources, concentrations,
and impact on selected freshwater lakes as a basis for formulating
comprehensive and coordinated national, regional, and state management
practices relating to point—source discharge reduction and non—point
source pollution abatement in lake watersheds.
ANALYTIC APPROACH
The mathematical and statistical procedures selected for the
Survey’s eutrophication analysis are based on related concepts that:
a. A generalized representation or model relating
sources, concentrations, and impacts can be constructed.
b. By applying measurements of relevant parameters
associated with lake degradation, the generalized model
can be transformed into an operational representation of
a lake, its drainage basin, and related nutrients.
c. With such a transformation, an assessment of the
potential for eutrophication control can be made.
LAKE ANALYSIS
In this report, the first stage of evaluation of lake and water-
shed data collected from the study lake and its drainage basin is
documented. The report is formatted to provide state environmental
agencies with specific information for basin planning [ 3O3(e)], water
quality criteria/standards review [ 3O3(c)], clean lakes [ 314(a,b)],
and water quality monitoring [ lO6 and §305(b)] activities mandated
by the Federal Water Pollution Control Act Amendments of 1972.
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111
Beyond the single lake analysis, broader based correlations
between nutrient concentrations (and loading) and trophic condi-
tion are being made to advance the rationale and data base for
refinement of nutrient water quality criteria for the Nation’s
fresh water lakes. Likewise, multivariate evaluations for the
relationships between land use, nutrient export, and trophic
condition, by lake class or use, are being developed to assist
in the formulation of planning guidelines and policies by EPA
and to augment plans implementation by the states.
ACKNOWLEDGMENT
The staff of the National Eutrophication Survey (Office of
Research & Development, U. S. Environmental Protection Agency)
expresses sincere appreciation to the Illinois Environmental
Protection Agency for professional Involvement and to the Illinois
National Guard for conducting the tributary sampling phase of the
Survey.
Dr. Richard H. Briceland, Director of the Illinois Environ-
mental Protection Agency; and Ronald M. Barganz, State Survey
Coordinator, and John J. Forneris, Manager of Region III, Field
Operations Section of the Division of Water Pollution Control,
provided invaluable lake documentation and counsel during the
Survey, reviewed the preliminary reports, and provided critiques
most useful in the preparation of this Working Paper series.
Major General Harold R. Patton, the Adjutant General of
Illinois, and Project Officer Colonel Daniel L. Fane, who directed
the volunteer efforts of the Illinois National Guardsmen, are also
gratefully acknowledged for their assistance to the Survey.
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iv
NATIONAL EUTROPHICATION SURVEY
STUDY LAKES
STATE OF ILLINOIS
LAKE NAME COUNTY
Baldwin Randolph
Bloomington McLean
Carlyle Bond, Clinton, Fayette
Cedar Lake
Charleston Coles
Coffeen Montgomery
Crab Orchard Jackson, Williamson
Decatur Macon
DePue Bureau
East Loon Lake
Fox Lake
Grass Lake
Highland Silver Madison
Holiday LaSalle
Horseshoe Madison
Long Lake
Lou Yaeger Montgomery
Marie Lake
Old Ben Mine Franklin
Pistakee Lake, McHenry
Raccoon Marion
Rend Franklin, Jefferson
Sangchris Christian
Shelbyville Moultrie, Shelby
Slocum Lake
Springfield Sangamon
Storey Knox
Vandalia Fayette
Vermilion Vermilion
Wee Ma Tuk Fulton
Wonder McHenry
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02’
01’
OLD BEN MINE
RESERVOIR
Lake Sampling Site
Sewage Treatment Plant
Drainage Area Boundary
O 1/41 2
Map
(
Location
•4)
/-.
I
/ -
OLD BEN MINE
RESERVOIR
1•
x
Sesser
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OLD BEN MINE RESERVOIR
STORET NO. 1765
I. INTRODUCTION
Old Ben Mine Reservoir was included in the National Eutrophication
Survey as a water body of interest to the Illinois Environmental Protection
Agency. Tributaries and nutrient sources were not sampled, and this re-
port primarily relates to the reservoir sampling data.
II. CONCLUSIONS
A. Trophic Condition:
Survey data indicate that Old Ben Mine Reservoir is eutrophic.
It ranked 22nd in overall trophic quality when the 31 Illinois
lakes sampled in 1973 were compared using a combination of six
lake parameters*. Thirty of the lakes had less median total
and dissolved phosphorus, five had less median inorganic nitrogen,
18 had less mean chlorophyll a, and 13 had greater mean Secchi
disc transparency. Depression of dissolved oxygen occurred at
1.5 meters in depth in August, 1973.
The Survey limnologists noted floating and emergent macro-
phytes during all three visits.
B. Rate-Limiting Nutrient:
The algal assay results Indicate that the reservoir was nitro-
gen limited at the time the sample was collected (05/11/73). The
* See Appendix A.
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2
reservoir data indicate nitrogen limitation at the other
sampling times as well.
C. Nutrient Controllability:
1. Point sources--The municipal treatment plant at Sesser
was the only known phosphorus source impacting the reservoir
during the sampling year. A total of 1,925 kg P was estimated
to have been contributed by this source and resulted in a point-
source loading rate of 4.48 g/m 2 /yr.
Based on the reservoir data and the data of other Illinois
lakes studied, this reservoir exhibits symptoms typical of a
highly eutrophic lake and should show improvement if phosphorus
control is instituted at Sesser.
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III. LAKE AND DRAINAGE BASIN CHARACTERISTICS1"
A. Lake Morphometry*:
1. Surface area: 0.43 kilometers2.
2. Mean depth: 1.2 meters.
3. Maximum depth: >1.5 meters.
4. Volume: 0.516 x 106 m3.
B. Precipitation**:
1. Year of sampling: 124.0 centimeters
2. Mean annual: 112.3 centimeters.
t Table of metric conversions—Appendix B.
* Forneris, 1973.
** See Working Paper No. 175, "...Survey Methods, 1973-1976"
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4
IV. LAKE WATER QUALITY SUMMARY
Old Ben Mine Reservoir was sampled three times dLlring the open-water
season r f J373 by me n of a pontoon-equi”pe Hue ’ belo Dt, . ach
tine, samples for physical and chemical parameters were collected from
two depths at a single station on the lake (see map, page v). During
each visit, a single depth-integrated (near bottom to surface) sample
was collected for phytoplankton identification and enumeration, and a
similar sample was taken for chlorophyll a analysis. During the first
visit, a single 18.9—liter depth-integrated sample was collected for
algal assays. The maximum depth sampled was 1.5 meters.
The sampling results are presented in full in Appendix C and are
summarized in the following table.
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A. SUMMAMY OF PHYSICAL AN() CHEMICAL Ct4A4At.TERISTICS FOR OLD 8EN MINE RESERVOIR
STURET COOE 1765
1ST SAMPLING ( 5/11/73) 2ND SAMPLING 8/ 8/73) 3RD SAMPLING (10/18/73)
1 SITES 1 SITES 1 SITES
PARAMETER RMNGL MEAN MEDIAN RANL,L MEAN MEDIAN RANGE MEAN MEDIAN
TEMP (C) 18.1 — 18.8 IH.4 18.4 28.2 — 29.3 28.7 28.7 17.7 — 17.8 17.7 17.7
0155 OXY (MG/L) 3.8 - 3.8 3.8 3.8 3.8 — 7.6 5.7 5.7 9.6 — 9.6 9.6 9.6
CNDCTVY MCROMO 435. - ‘ . .0. ‘.3 s. 438. 122. — 123. 123. 123. 1375. — 1376. 1376. 1376.
PH (STAND UNITS) 7.5 - 7.6 7.5 7.5 7.6 — 8.3 7.9 7.9 8.0 — 8.0 8.0 8.0
TOT ALK (MG/L) 66. — 67. 67. 7. 128. — lii. 130. 130. 148. — 148. 148. 148.
TOT P (MUlL) 0.374 - 0.416 0.395 0.395 0.940 — 0.972 0.956 0.956 0.920 — 0.960 0.930 0.930
ONTHU P (MG/U 0.333 — 0.33 0.335 0.335 0.s18 — 0.672 0.595 0.595 0.632 — 0.63’. 0.633 0.633 “
N02.NO3 (MG/LI u.5 ’ .0 - 0.550 0.545 0.5’.5 0.080 — 0.130 0.105 0.105 0.060 — 0.070 0.065 0.065
AMMONIA (MG/LI 0.310 — 0.420 0.36, 0.3b 0.0 0 — 0.120 0.100 0.100 0.060 — 0.060 0.060 0.060
KJEL N (MG/LI 1.100 — 1.100 1.100 1.100 1.200 — 2.000 1.600 1.600 1.600 — 1.900 1.150 1.750
INOR(, N (MG/LI 0.860 - (1.960 0.910 0.910 o.LeQ — 0.250 0.205 0.205 0.120 — 0.130 0.125 0.125
TOIAL N (MG/LI 1.640 - 1.650 1.645 1.b4 1.280 — 2.130 1.705 1.705 1.660 — 1.970 1.815 1.815
CHL, (PYL A COG/LI 10.0 - 10.0 10.0 10.0 59.7 — 59.7 59.7 59.7 24.6 — 24.6 24.6 24.6
SELCrII (MLTERS) 0.5 — 0.5 0.5 0.5 0.7 — 0.7 0.7 0.7 0.5 — 0.S 0.5 0.5
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6
B. Biological characteristics:
1. Phytoplankton -
Sampling Dominant Algal Units
Date Genera per ml
05/11/73 1. Flagellates 4,759
2. Cyclotella p. . 1,175
3. cylindrocystis p. 602
4. Scenedesmus p_. 572
5. Mallomonas .p.. 120
Other genera 724
Total 7,952
08/08/73 1. Oscillatoria p_. 6,855
2. Cyclotella 5,429
3. Carteria . R• 4,362
4. Merismopedia p... 2,037
5. Cryptonionas p. 1,870
Other genera 9,538
Total 30,091
10/18/73 1. Stephanodiscus p. 7,011
2. Kirchneriella p. 5,075
3. Scenedesmus p. 4,941
4. Flagellates 3,472
5. Cyclotella . a• 2,471
Other genera 5,943
Total 28,913
2. Chlorophyll a -
Sampling Station Chlorophyll a
Date Number ( pg/l )
05/11/73 01 10.0
08/08/73 01 59.7
10/18/73 01 24.6
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7
C. Limiting Nutrient Study:
1. Autoclaved, filtered, and nutrient spiked —
Ortho P Inorganic N
- Conc. (mg/l) Conc. (mg/i ) ______________
0.348 0.870
0.398 0.870
N 0.398 1.870
0.348 1.870
2. Discussion —
The control yield of the assay alga, Selenastrum capri-
cornutum , indicates that the potential primary productivity
of Old Ben Mine Reservoir was very high at the time the sample
was collected. The yield resulting from the 0.050 mg/i ortho-
phosphorus spike was not significantly different from the
control, but the nitrogen only spike showed a marked increase
in yield as compared to the control. Based on these results,
nitrogen limitation is indicated.
The reservoir data indicate nitrogen limitation at the
other sampling times as well; the mean inorganic nitrogen!
orthophosphorus ratios were less than 1/1 in August and
October.
Spike (mg/i )
Control
0.050 P
0.050 P + 1.0
1.0 N
Maximum yield
mg/1-dry wt. )
20.9
23.0
40.9
42.2
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8
V. NUTRIENT LOADINGS
Tributaries and nutrient sources were not sampled because this
reservoir was included in the National Eutrophication Survey as a
water body of interest to the Illinois Environmental Protection
Agency.
Nutrient loads from the Village of Sesser were estimated at 1.134
kg P and 3.401 kg N/capita/year.
A. Waste Sources:
1. Known muncipal -
Pop. Mean Flow Receiving
Name Served* Treatment ( m 3 /d)** Water
Sesser 1,700 trickling 643.4 JackIe Branch
filter
2. Known industrial - None
* Anonymous, 1972.
** Estimated at 0.3785 m 3 /capita/day.
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9
B. Annual Total Phosphorus Loading - Average Year:
1. Inputs -
kg P1
Source yr
a. Tributaries (non-point load) -
None sampled
b. Minor tributaries & immediate
drainage (non-point load) -
c. Known municipal SIP’s -
Sesser 1 ,925
d. Septic tanks — Unknown
e. Known industrial - None
f. Direct precipitation* - 10
Total 1 ,935
* See Working Paper No. 175.
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10
C. Annual Total Nitrogen Loading - Average Year:
1. Inputs -
kg N I
Source yr
a. Tributaries (non-point load) -
None sampled
b. Minor tributaries & immediate
drainage (non-point load) -
c. Known municipal STP’s -
Sesser 5,785
d. Septic tanks - Unknown
e. Known industrial - None
f. Direct precipitation* - 465
Total 6,250
D. Yearly Loading Rates:
Total Phosphorus Total Nitrogen
grams/m 2 /yr at least 4.50 at least 14.5
* See Working Paper No. 175.
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11
VI. LITERATURE REVIEWED
Anonymous, 1972. Wastewater treatment works data book. IL Env.
Prot. Agency, Springfield.
Forneris, John J., 1973. Personal communication (lake morphometry).
IL Env. Prot. Agency, Springfield.
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VII. APPENDICES
APPENDIX A
LAKE RANKINGS
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LAKE DATA TO BE USED IN HANK INGS
LAKE
CODE
1703
1706
1708
1T11
1712
171*
1725
1726
1727
1733
1735
1739
17*0
1742
1748
1750
1751
1758
1753
1754
1755
175&
J757
1758
1759
1761
1762
1763
LAKE NAME
LAKE BLOOM1NGTON
LAKE CARLYLE
LAKE CHARLESTON
COFFEE* LAKE
CRAB ORCHARD LAKE
LAKE OECATUR
LONG LAKE
LAKE LOU YAEGER
LAKE MARIE
PISTAKEE LAKE
REND LAKE
LAKE SMELHrVILLE
SILVER LAKE (HIGHLAND)
LAKE SPRINGFIELD
VERMILION LAKE
WONDER LAKE
LAKE STORY
DEPUE LAKE
LAKE SANGCnRIS
LAKE HOL10AY
FOX LAKE
GRASS LAKE
EAST LOON LAKE
SLOCUM LAKE
CEDAR LAKE
LAKE WtMATUK
RACCOON LAKE
BALDWIN LAKE
HEDIAM
TOTAL P
0.050
0.084
0.160
0.032
0.082
0.129
0.7«4
0.1
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LAKE DATA TO BE uSE IN RANKINGS
LAKE
C ODE
I
1
LAKE NAME
LAKI VANDAL IA
OLO BEN MINE i1ISERVON
HUR$EShOE LAKE
MF I
M D1AN
OO—
MEAN
I D —
MEu1 .
TLI;L 1’
INO i , N
MEAN SEC
CdLC) A
D•)
0I O T ’
O.1 1
0.430
.7a.H1
I1.27
z ’. .u
O. J J
0.93% )
0.205
‘.73 j33
31.43 )
I1.20u
0,i’
0.1?i
0.705
t . OG
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PERCENT OF LAKES WITH HIGHER VALUES INUMBER OF LAKES WITH HIGHER VALUES)
LAKE
CODE
LAKE NAME
MEDIAN
TOTAL P
MEDIAN
INORD
N
500-
MEAN SEC
MEAN
CHLORA
15-
HIN DO
MEDIAN
0155 ORTHO P
INDEX
No
1703
LAKE 8LOOMINGTON
88 (
26)
0 1
0)
80 I
24)
47 1
14)
13 I 2)
68
I 20)
296
1706
LAKE CARLYLE
63 I
19)
40 I
12)
63 I
19)
63 (
19)
63 I 19)
53
I 16)
345
1708
LAKE CHARLESTON
37 (
II)
7 I
2)
0 I
0)
77 I
23)
77 I 23)
27
I 6)
225
1711
COFFEEN LAKE
97 I
29)
77 I
23)
93 I
28)
93 I
28)
2 1 0)
92
I 27)
454
1712
CRAB ORCHARD LAKE
67 1
20)
90 I
27)
43 1
13)
20 I
6)
42 1 12)
85
1 25)
347
1714
LAKE DECATUR
40 C
12)
13 1
4)
53 1
16)
33 1
10)
30 1 8)
32
1 9)
201
1725
LONG LAKE
7 C
2)
43 I
13)
40 I
12)
30 1
9)
72 1 21)
3
I 1)
195
1726
LAKE LOU YAEGER
30 C
9)
37 I
II)
7 I
2)
87 I
26)
57 I 17)
23
I 7)
241
1727
LAKE MARIE
60 1
18)
68
20)
73 I
22)
37 I
11)
23 7)
42
1 12)
303
1733
PISTAKEE LAKE
27 1
8)
68 I
20)
23 1
7)
13 I
4)
90 I 27)
32
I 9)
253
1735
REND LAKE
77 C
23)
80 I
24)
70 1
21)
50 I
15)
53 I 16)
92
I 27)
422
1739
LAKE SHELBYVILLE
83 I
25)
17 1
5)
83 I
25)
70 I
21)
13 I 2)
73
I 22)
339
1740
SILVER LAKE (HIGHLAND)
20 C
6)
47 1
14)
10 1
3)
97 I
29)
13 I 2)
42
I 12)
229
1742
LAKE SPRINGFIELD
53 I
16)
20 I
6)
33 I
10)
73 I
22)
67 1 20)
37
I 11)
283
1748
VERMILION LAKE
50 I
15)
3 1
1)
47 I 14)
43 1
13)
37 I 11)
47
I 14)
227
1750
WONDER LAKE
13 I
4)
50 I
15)
20 1 6)
7 1
2)
80 I 24)
13
1 4)
183
1751
LAKE STORY
73 I
22)
27 I
8)
90 I 27)
67 I
20)
13 I 2)
63
I 19)
333
1752
DEPUE LAKE
10 I
3)
10 C
3)
3 I I)
23 I
7)
83 I 25)
10
I 3)
139
1753
LAKE SANGCHRIS
88 I
26)
30 1
9)
b7 1 20)
57 I
17)
30 1 8)
97
1 29)
369
1754
LAKE HOLIOAY
33 I
10)
23 C
7)
27 I 8)
27 1
8)
87
1 26)
50
I 15)
247
1755
FOX LAKE
23 I
7)
63 I
19)
17 1 5)
17 I
5)
72
1 21)
20
1 6)
212
1756
GRASS LAKE
17 I
5)
53 I
16)
SO ( 15)
10 I
3)
97
I 29)
17
I 5)
24 ’.
1757
EAST LOON LAKE
70 1
21)
100 I
30)
97 1 29)
53 I
16)
2
I 0)
77
1 23)
399
1758
SLOCUM LAKE
3 (
I)
87 I
26)
13 I 4)
0 I
0)
100
( 30)
7
I 2)
210
1759
CEDAR LAKE
100 I
30)
93 I
28)
100 1 30)
100 1
30)
50
I 15)
85
I 25)
528
1761
LAKE EHATUK
80 I
24)
33 I
10)
77 1 23)
90 I
27)
30
I 8)
57
I 17)
367
1762
RACCOON LAKE
57 I
17)
73 I
22)
30 1 9)
60 I
18)
42
I 12)
68
1 20)
330
1763 BALOIIN LAKE
93 I 28) 97 I 29) 87 I 26 1 80 I 24) 47 I 14) 100 1 30)
504
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PERCENT OF LAKES WITH HIGHER VALUES (NUMBER OF LAKES WITH HIGHER VALUES)
LAKE MEDIAN MEDIAN 500— MEAN 15- MEDIAN
CODE LAKE NAME TOTAL P INORG N MEAN SEC CHLORA MIN DO DISS OMTP-4O P NO
1764 LAKE VANDALIA 47 ( 14) 60 ( 18) 60 C 18) 83 C 25) 13 C 2) 60 1 18) 323
1765 OLD EN MINE RESERVOIR 0 C 0) 83 C 25) 57 C 17) 40 ( 12) 60 18) 0 ( 0) 240
1766 HORSESHOE LAKE 43 C 13) 57 1 17) 37 1 11) 3 ( 1) 93 1 28) 80 C 24) 313
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LAKES RANKED BY INDEK NOS.
RANK LAKE CODE LAKE NAME INDEX NO
1 1159 CEDAR LAKE 528
2 1163 BALDwIN LAKE 504
3 1711 COFFEEN LAKE 454
4 1735 REND LAKE 422
5 1757 EAST LOON LAKE 399
6 1753 LAKE SANGCr4RIS 369
7 1761 LAKE WEMATUK 367
8 1112 CRAB ORCHARD LAKE 347
9 1706 LAKE CARLYLE 345
10 1739 LAKE SHELBYVILLE 339
II 1751 LAKE STORY 333
12 1762 RACCOON LAKE 330
13 1764 LAKE VANOALIA 323
14 1766 HORSESHOE LAKE 313
15 1727 LAKE MARIE 303
16 1703 LAKE BLOOMINGTON 296
I? 1142 LAKE SPRINGFIELD 183
18 1733 PISTAKEE LAKE 253
19 1756 LAKE HOLIDAY 247
20 1756 GRASS LAKE 244
21 1726 LAKE LOU YAEGER 241
22 1765 OLD BEN MINE RESERVOIR 240
23 1740 SILVER LAKE (HIGHLAND) 229
24 1748 VE 41LION LAKE 227
25 170d LAKE CHARLESTON 225
26 1755 FOX LAKE 212
27 1758 SLOCUM LAKE 210
28 1714 LA’ E DECATu- 201
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LAKES RANKED BY INDEA NOS.
RANK LAKE CODE LAKE NAME INDEX NO
29 1725 LONG LAKE 195
30 1750 WONDER LAKE 183
31 1752 DEPUE LAKE 139
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APPENDIX B
CONVERSIONS FACTORS
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CONVERSION FACTORS
1-lectares x 2.471 = acres
Kilometers x 0.6214 = miles
Meters x 3.281 = feet
Cubic meters x 8.107 x 10 acre/feet
Square kilometers x 0.3861 = square miles
Cubic meters/sec x 35.315 = cubic feet/sec
Centimeters x 0.3937 = inches
Kilograms x 2.205 = pounds
Kilograms/square kilometer x 5.711 = lbs/square mile
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APPENDIX C
PHYSICAL and CHEMICAL DATA
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SIORET RETRIEVAL DATE 75/10/23
176501
38 U& 15.0 089 00 45.0
OLD BEN MINE WESERVOIR
17055 ILLINOIS
1 IEPALES 2111202
3 0008 FEET DEPTH
UO010 00300 00077 00094 00400 00410 00610 00625 00630 00671
DATE TIME DEPTH WATER 00 TRANSP CNDUCTVY PH T ALK NH3—N TOT KJEL NO2 NO3 PHOS—DIS
FROM OF TEMP SECCHI FIELD CACO3 TOTAL N N—TOTAL ORTHO
TO DAY FEET CENT MG/L INCHES MICROMHO SO MG/L M&/L MG/L ML/L MG/L P
73/05/11 12 25 0000 18.8 18 440 7.60 66 0.310 1.100 0.550 0.338
12 25 0004 18.1 3.8 435 7.50 67 0.420 1.100 0.540 0.333
73/08/08 13 15 0000 29.3 7.6 8 123 8.30 128 0.120 2.000 0.130 0.672
13 15 0005 28.2 3.8 122 7.60 131 0.080 1.200 0.080 0.518
73/10/18 11 19 0000 17.7 19 1376 8.00 148 0.060 1.900 0.070 0.632
11 19 0003 17.8 9.6 1375 8.00 148 0.060 1.600 0.060 0.634
00665 32217
DAft. TIME DEPTH Pi-IOS—TOT CHLRPHYL
FI OH OF A
TO DAY FEET MG/L P UG/L
73/05/11 12 25 0000 0.374 10.0
12 25 0004 0.416
73/08/08 13 15 0000 0.940 59.7
13 15 0005 0.972
73/10/Id 11 19 0000 0.940 24.6
11 19 0003 0.920
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