U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
SPIRIT LAKE
DICKINSON COUNTY
IOW
EPAEGIONVII
WORKING PAPER No, 506
CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
"WTG.P.O. 699-440
-------
REPORT
ON
SPIRIT LAKE
DICKINSON COUNTY
IOWA
EPA REGION VII
WORKING PAPER No, 506
WITH THE COOPERATION OF THE
IOWA DEPARTMENT OF ENVIRONMENTAL QUALITY
AND THE
IOWA NATIONAL GUARD
AUGUST, 1976
-------
CONTENTS
Page
Foreword ii
List of Iowa Study Lakes iv
Lake and Drainage Area Map v
Sections
I. Introduction 1
II. Conclusions 2
III. Lake and Drainage Basin Characteristics 4
IV. Lake Water Quality Summary 5
V. Literature Reviewed 9
VI. Appendices 10
-------
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 freshwater 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 [§303(e)J, water
quality criteria/standards review [§303(c)L clean lakes [§314(a,b)],
and water quality monitoring [§106 and §305(b)] activities mandated
by the Federal Water Pollution Control Act Amendments of 1972.
-------
Ill
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
freshwater 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 Iowa Department of Environ-
mental Quality for professional involvement, to the Iowa National
Guard for conducting the tributary sampling phase of the Survey,
and to those wastewater treatment plant operators who voluntarily
provided effluent samples and flow data.
The staff of the Water Quality Division of the Department of
Environmental Quality 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 Joseph G. May, the Adjutant General of Iowa,
and Project Officer Colonel Cleadeth P. Woods, who directed the
volunteer efforts of the Iowa National Guardsmen, are also grate-
fully acknowledged for their assistance to the Survey.
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iv
LAKE NAME
Ahquabi
Big Creek Reservoir
Black Hawk
Clear
Darling
Lost Island
MacBride
Prairie Rose
Rathbun Reservoir
Red Rock Reservoir
Rock Creek
Silver
Spirit
Vi king
West Okoboji
NATIONAL EUTROPHICATION SURVEY
STUDY LAKES
STATE OF IOWA
COUNTY
Warren
Polk
Sac
Cerro Gordo
Washington
Clay, Palo Alto
Johnson
Shelby
Appanoose, Wayne
Marion
Jasper
Worth
Dickinson
Montgomery
Dickinson
-------
MINNESOTA
WESTOKOBOJI LAKE
& SPIRIT LAKE
X Lake Sampling Site
0 1234
1 2
Scale
s Km.
3Mi.
43'3tf~
4320—
9510
9500'
-------
SPIRIT LAKE
STORE! NO. 1913
I. INTRODUCTION*:
Spirit Lake was included in the National Eutrophication Survey
as a water body of interest to the Iowa Department of Environmental
Quality. Tributaries and nutrient sources were not sampled, and
this report relates only to the lake sampling data.
Spirit Lake is one of a chain of natural lakes collectively known
as the Iowa Great Lakes. Glacial in origin, the lake is quite shallow
but has the largest surface area of any of the natural lakes in the
state. Besides being used as a public water supply, it is a valuable
recreational asset. Activities such as camping, fishing, and swimming
attract many Iowa residents and out-of-state visitors; and private
residences, cabins, and commercial establishments ring the shoreline.
Abundant gamefish present include perch, smallmouth and largemouth bass,
and walleyes. Some bluegills, crappies, and channel catfish can also be
caught. The watershed is almost entirely agricultural.
All of the Iowa Great Lakes have been classified as eutrophic but
in varying degrees. Nuisance algal blooms are most severe in Lower Gar
Lake and Lake East Okoboji, although all of the lakes have summer algae
problems. There has been an apparent decrease of macrophyte and muolTuscan
species diversity in recent years, as well as an increase in the abundance
* Description of the lake from Bachmann and Jones (1974).
-------
2
of blue-green algae. However, sediment core samples indicate
that the Iowa Great Lakes chain has been eutrophic for several
thousand years.
It has been estimated that the lake chain as a whole
receives only 3% of the total phosphorus load from urban
sources with the remainder contributed by agricultural runoff
and other non-point sources; feedlots contribute about 10%
of the phosphorus load to Spirit Lake.
II. CONCLUSIONS
A. Trophic Condition:
Survey data indicate that Spirit Lake is eutrophic. It
ranked first in overall trophic quality when the 15 Iowa lakes
and reservoirs sampled in 1974 were compared using a combination
of six water quality parameters*. However, based on their more
extensive studies, Bachman and Jones (op. cit.) consider West
Okoboji Lake to be of better overall trophic quality than
Spirit Lake.
None of the other Iowa water bodies had less median total
phosphorus and median orthophosphorus, three had less median inor-
ganic nitrogen and mean chlorophyll a_, and two had greater mean
Secchi disc transparency.
Survey limnologists observed some surface phytoplankton during
the July sampling at all stations.
B. Rate-Limiting Nutrient:
The algal assay results indicate that Spirit Lake was phos-
* See Appendix A.
-------
3
phorus limited at the time the sample was collected (04/23/74).
The lake data indicate phosphorus limitation at stations 1 and
2 in April but nitrogen limitation at station 3. Nitrogen limi-
tation is indicated at all three stations in September.
-------
III. LAKE AND DRAINAGE BASIN CHARACTERISTICS1"
A. Lake Morphometry :
1. Surface area: 23.00 kilometers2.
2. Mean depth: 5.5 meters.
3. Maximum depth: 7.3 meters.
4. Volume: 126.500 x 106 m3.
5. Mean hydraulic retention time: Unknown.
C. Precipitation*:
1. Year of sampling: 71.8 centimeters.
2. Mean annual: 70.5 centimeters.
t Table of metric conversions—Appendix B.
tt Harrison, 1975.
* See Working Paper No. 175, "...Survey Methods, 1973-1976",
-------
5
IV. LAKE WATER QUALITY SUMMARY
Spirit Lake was sampled three times during the open-water season
of 1974 by means of a pontoon-equipped Huey helicopter. Each time,
samples for physical and chemical parameters were collected from one
or more depths at three stations on the lake (see map, page v). During
each visit, a single depth-integrated (near bottom to surface) sample
was composited from the stations for phytoplankton identification
and enumeration; and during the first visit, a single 18.9-liter depth-
integrated sample was composited for algal assays. Also each time,
a depth-integrated sample was collected from each of the stations
for chlorophyll ^analysis. The maximum depths sampled were 4.6 meters
at station 1, 4.9 meters at station 2, and 4.6 meters at station 3.
The sampling results are presented in full in Appendix C and are
summarized in the following table (the July nutrient samples were
not preserved properly and were not analyzed).
-------
PARAMETER
TEMP (C)
DISS OXY (MG/L>
CNDCTVY (MCROMO)
PH (STAND UNITS)
TOT ALK (MG/L)
TOT P (MG/L>
ORTHO P (MG/L)
N02»N03 (MG/L)
AMMONIA (MG/L)
KJEL N (MG/L)
INORG N (MG/L)
TOTAL N (MG/L)
CHLBPYL A (UG/L)
SECCHI (METERS)
A. SUMMARY OF PHYSICAL AND
1ST SAMPLING ( 4/23/74)
3 SITES
CHEMICAL CHARACTERISTICS FOR SPIRIT LAKE
STORET CODE 1913
2ND SAMPLING ( 7/ 9/74)
3 SITES
3RD SAMPLING ( 9/23/74)
3 SITES
RANGE
8.5 -
10.0 -
332. -
8.4
186.
0.030
0.002
0.080
0.030
0.900
0.120
0.990
2.3
2.7
-
- 0
- 0
- 1
- 0
• 1
-
8.7
10.6
337.
8.4
193.
.049
• 019
.110
.050
.100
• 160
.210
2.6
3.7
MEAN
8.6
10.3
335.
8.4
191.
0.037
0.007
0.097
0*041
0«967
0.138
1.063
2.5
3.1
MEDIAN RANGE MEAN MEDIAN
8.7 24.1 - 24.9 24.6 24.6
10.3 6.0 - 8.2 7.6 8.0
335. 544. - 555. 549. 548.
0
0
0
0
1
0
1
8.4 8.6 - 8.7 8.6 8.6
.034 «•••»» -««•«•»*>•«»«•*»•«>***•
2.5 13.8 - 15.4 14.6 14.7
3.0 1.5 - 1.5 1.5 1.5
0
0
0
0
1
0
1
RANGE
15.2 -
9.0 -
367. -
8.3
167.
.038
.006
.020
.020
.200
.040
.220
19.5
1.1
-
- 0
- 0
- 0
- 0
- 1
- 0
- 1
-
15.5
9.4
369.
8.4
182.
.058
.013
.030
.040
.400
.060
.420
22.4
1.4
MEAN
15.3
9.2
368.
8.4
174.
0.045
0.009
0.021
0.030
1.278
0.051
1 .299
20.8
1.2
MEDIAN
15.3
9.2
368.
8.4
173.
0.043
0.009
0.020
0.030
1.300
0.050
1.320
20.4
1.2
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B. Biological Characteristics:
1. Phytoplankton -
Sampling
Date
04/23/74
07/09/74
09/23/74
2. Chlorophyll a_ -
Sampling
Date
04/23/74
07/09/74
09/23/74
Dominant
Genera
1. Flagellates
2. Dinobryon sp.
3. Cryptomonas sp.
4. Aphanothece sp.
5. Dinoflagellates
Other genera
Total
1. Aphanocapsa sp.
2. Aphanizomenon sp.
3. Schroederia sp.
4. Anabaena sp.
5. Cryptomonas sp.
Other genera
Total
1. Aphanothece sp.
2. Anabaena sp.
3. Aphanizomenon sp.
4. Coelosphaerium sp.
5. Oscillatoria sp.
Other genera
Total
Station
Number
1
2
3
1
2
3
1
2
3
Algal Units
per ml
912
240
144
96
48
97
1,537
1,569
262
262
232
145
174
2,644
1,182
734
326
285
245
937
3,709
Chlorophyll a_
(yg/1)
2.6
2.3
2.5
15.4
14.7
13.8
22.
20.
19.5
-------
8
Limiting Nutrient Study:
1. Autoclaved, filtered, and nutrient spiked -
Ortho P Inorganic N Maximum yield
Spike (mg/1) Cone, (mg/1) Cone, (mg/1) (mg/l-dry wt.)
Control 0.005 0.109 0.1
0.050 P 0.055 0.109 3.1
0.050 P + 1.0 N 0.055 1.109 16.1
1.0 N 0.005 1.109 0.1
2. Discussion -
The control yield of the assay alga, Selenastrum capri-
cornutum, indicates that the potential primary productivity
of Spirit Lake was low at the time the assay sample was
taken (04/23/74). The results also indicate phosphorus limi-
tation at that time. Note the significant increase in yield
when only orthophosphorus was added and the lack of yield
response when only nitrogen was added.
The lake data indicate phosphorus limitation in April at
stations 1 and 2; i.e., the mean inorganic nitrogen to ortho-
phosphorus ratios were 45 to 1 and 33 to 1, respectively.
However, nitrogen limitation is- indicated at station 3 (the
mean N/P ratio was 11/1).
The September lake data indicate nitrogen limitation at
all stations; i.e., the mean N/P ratios were 6/1 or less,
and nitrogen limitation would be expected.
-------
V. LITERATURE REVIEWED
Anonymous, 1974. Management plan for water quality—Iowa Great
Lakes. E. A. Hickok and Assoc., Wayzata, Minnesota.
Bachmann, Roger W., and John R. Jones, 1974. Water quality in
the Iowa Great Lakes. MS, Dept. of Zoo. & Ent., IA St. U.,
Ames.
Harrison, Harry M., 1975. Personal communication (lake morphometry).
IA Cons. Comm., Des Moines.
-------
VI. APPENDICES
APPENDIX A
LAKE RANKINGS
-------
LAKE DATA TO BE USED IN RANKlNGb
LAKE
CODE LAKE NAME
1901 LAKE ACOUA6I
1902 8IG CREEK RESERVOIR
1903 SLACK HAWK LAKE
1904 CLEAR LAKE
1905 LAKE DARLING
1906 LOST ISLAND LAKE
1907 LAKE MACBPIOE
1908 PRAIRIE ROSE LAKE
1909 RATHBUN RESERVOIR
1910 RED ROCK LAKE
1911 ROCK CREEK LAKE
1912 SILVER LAKE
1913 SPIRIT LAKE
1914 VIKING LAKE
1915 WEST LAKE OKOBOJI
MEDIAN
TOTAu H
0.06?
0.046
0.185
0.059
0.077
0.146
0.061
0.056
0.071
0.180
0.065
0.193
0.041
0.075
0.046
MEDIAN
1NO«G N
0.3J5
6.465
0.130
0.070
1.475
0.065
2.035
0.210
1.170
1.880
1.400
0.565
0.090
0.130
0.060
500-
MEAN SEC
469.333
436.500
488.167
465.125
482.500
421.167
458.444
463.667
475.889
473.400
480.500
482.667
422.667
459.000
380.444
MEAN
CuLOrtA
8.600
16.867
49.740
17.400
13.817
36.100
17.067
17.350
12.039
14.730
18.367
95.300
12.622
26.033
7.722
15-
HIN DO
8.200
14.800
15.000
8.600
9.200
8.400
15.000
8.600
14.000
14.000
8.400
10.000
9.000
14.200
15.000
MEDIAN
DISS OKTrtO P
0.009
0.011
0.020
0.010
0.012
0.021
0.010
0.010
0.008
0.104
0.007
0.034
0.007
0.017
0.017
-------
PERCENT OF LAKES WITH HIGHER VALUES (NUMBER OF LAKES WITH HIGHER VALUES)
LAKE
CODE LAKE NAME
1901 LAKE ACOUABI
190? BIG CREEK RESERVOIR
1903 BLACK HAWK LAKE
1904 CLEAR LAKE
1905 LAKE DARLING
1906 LOST ISLAND LAKE
1907 LAKE MACBRIDE
1908 PRAIRIE ROSE LAKE
1909 RATHBUN RESERVOIR
1910 RED ROCK LAKE
1911 ROCK CREEK LAKE
1912 SILVER LAKE
1913 SPIRIT LAKE
191* VIKING LAKE
1915 WEST LAKE OKOBOJI
MEDIAN
TOTAL P
57 (
69 (
7 (
71 (
29 (
21 (
64 (
79 (
43 (
1* (
50 (
0 (
100 (
36 (
89 (
8)
12)
1)
10)
4)
3)
9)
11)
6)
2)
7)
0)
14)
5)
12)
MEDIAN
INO*G N
50 (
0 (
foB (
86 (
21 (
93 (
7 (
57 (
36 (
14 (
29 <
43 <
79 (
68 (
100 (
7)
0)
9)
12)
3)
13)
1)
8)
5)
2>
4)
6)
11)
9)
14)
500-
MEAN SEC
43 (
79 (
0 (
50 (
14 (
93 (
71 (
57 (
29 (
36 (
21 (
7 (
86 (
64 (
100 (
6)
11)
0)
7)
2)
13)
10)
8)
4)
5)
3)
1)
12)
9)
14)
MEAN
CHLORA
93 (
57 (
7 (
36 (
71 (
1* (
50 <
43 <
86 (
64 (
29 (
0 (
79 (
21 (
100 (
13)
8)
1)
5)
10)
2)
7)
6)
12>
9)
4)
0)
11)
3)
14)
15-
MIN DO
100
21
7
75
57
89
7
75
39
39
89
50
64
29
7
I 14)
( 3)
( 0)
( 10)
( 8)
( 12)
( 0)
( 10)
( 5)
( 5)
( 12)
< 7)
( 9)
( 4)
( 0)
MEDIAN
DISS ORTHO P
79 (
50 (
21 (
64 <
43 (
14 (
64 (
64 {
86 (
0 (
96 <
7 (
96 (
32 (
32 (
11)
7)
3)
8)
6)
2)
8)
8)
12)
0)
13)
1)
13)
4)
4)
INDEX
NO
422
296
110
382
235
324
263
375
319
167
314
107
504
250
428
-------
LAKES RANKED 8V INDEX NOS.
RANK LAKE CODE LAKE NAME INDEX NO
1 1913 SPIRIT LAKE 504
2 1915 WEST LAKE OK080JI 428
3 1901 LAKE ACOUABI 422
4 1904 CLEAR LAKE 382
5 1908 PRAIRIE ROSE LAKE 375
6 1906 LOST ISLAND LAKE 324
7 1909 RATHBUN RESERVOIR 319
8 1911 ROCK CREEK LAKE 314
9 1902 BIG CREEK RESERVOIR 296
19 1907 LAKE MACBRIDE 263
11 1914 VIKING LAKE 250
12 1905 LAKE DARLING 235
13 1910 RED ROCK LAKE 167
14 1903 BLACK HAWK LAKE 110
15 1912 SILVER LAKE 107
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APPENDIX B
CONVERSION FACTORS
-------
CONVERSION FACTORS
Hectares 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 = Ibs/square mile
-------
APPENDIX C
PHYSICAL and CHEMICAL DATA
-------
STOREf RETRIEVAL DATE 7b/l'J/21
191301
43 27 21.0 095 06 08.0
SPIRIT LAKE
19 IOWA
DATE TIME DEPTH
FROM OF
TO DAY FEET
74/04/23 10 00 0000
10 00 0005
10 00 0015
74/07/09 14 ?5 0000
14 25 0005
14 25 0015
74/^9/23 14 55 0000
14 55 0005
14 55 0014
11EPALES
3
2111202
0019 FEET
DEPTH
00010
WATER
TtMP
CENT
8.7
8.7
8.7
24.7
24.6
24. 1
15.3
15.3
15.3
00300
00
MG/L
10.4
10.4
6.0
a.o
7.6
9.0
9.4
9.2
00077
TRANSP
SECCHI
INCHES
108
60
54
00094
CNDUCTVY
FIELD
MICROMHO
336
334
337
555
552
553
368
368
368
00400
PH
SU
8.40
8.40
8.40
8.60
8.60
8.60
8.32
8.34
8.39
00410
T ALK
CAC03
MG/L
186
190
192
173
176
173
00610
NH3-N
TOTAL
MG/L
0.040
0.040
0.040
0.030
0.030
0.030
00625
TOT KJEL
N
MG/L
0.900
0.900
1.000
1.300
1.-300
1.400
00630
N02&N03
N-TOTAL
MG/L
0.100
0.110
0.090
0.020K
0.020
0.020
00671
PHOS-DIS
ORTHO
MG/L P
0.002
0.006
0.004
0.006
0.008
0.012
DATE TIME DEPTH
FROM OF
TO DAY FEET
74/04/23 10 00 0000
10 00 0005
10 00 0015
74/07/09 14 ?5 0000
74/09/23 14 55 0000
14 55 0005
14 55 0009
14 55 0014
J665
'b-TOf
i/L P
O.C31
C.043
0.049
•j.03d
0.041
32217
CHLRPHYL
A
'UG/L
2.6
15.4
2?. 4
00031
INCOT LT
REMNING
PERCENT
1.0
u.043
K VALUE KNOWN TO BE
LESS THAN INDICATED
-------
STORET RETRIEVAL DATE 75/10/21
191302
43 29 03.0 095 06 18.0
SPIRIT LAKE
19 IOWA
DATE
FROM
TO
74/04/23
74/07/09
74/09/23
TIME DEPTH
OF
(JAY FEET
10 20 0000
10 20 0005
10 20 0016
14 49 0000
14 49 0005
14 49 U016
14 00 0000
14 00 0005
14 00 0015
00010
•HATER
TEMP
CENT
8.7
8.7
8.7
24.6
?4.b
24.3
15.2
15.2
15.2
00300 00077 00094
DO TRANSP CNDUCTVY
SECChI HELD
MG/L INCHES MICROMHO
10.0
10.0
6.2
7.2
7.2
9.2
9.2
9.2
144
60
42
335
335
3J6
550
548
547
367
367
368
11EPALES
3
00^00
PH
ill
8.40
8.40
8.40
8.60
8.60
8.60
8.39
8.40
8.40
00410
T ALK
CAC03
MG/L
190
192
192
182
167
172
211
0020
00610
NH3-N
TOTAL
Mli/L
0.050
0.040
0.040
0.030
0.030
0.030
1202
FEET DEPTH
00625
TOT KJEL
N
MG/L
0.900
0.900
1.000
1.300
1.200
1.200
(JO 630
N02&N03
N-TOTAL
MG/L
0.100
0.090
0.080
0.020K
0.030
0.020K
00671
PMOS-iDIS
URTriO
MG/L P
0.004
0.004
0.004
0.013
0.009
0.012
00665
DATE TIME DEPTH PHOS-TOT
FROM OF
TO DAY FtET MG/L P
74/04/23 10 20 0000 0.030
10 20 0005 0.03d
1U 20 0016 0.030
74/07/09 14 49 0000
74/09/23 14 00 0000 0.05s
14 00 0005 u.U<*5
14 00 0009
14 00 0015 0.0«8
32217 00031
CHLRPHYL INCDT LT
A REMNING
UG/L PERCENT
2.3
14.7
20.4
1.0
K VALUE KNOWN TO BE
LESS THAN INDICATED
-------
STORET RETRIEVAL DATE 75/10/21
191303
43 29 20.0 095 03 58.0
SPIRIT LAKE
19 IOWA
DATE
FROM
TO
74/04/23
74/07/09
74/09/23
TIME OEPTH
OF
DAY FEET
10 35 0000
10 35 0005
10 35 0014
15 13 0000
15 13 U005
15 13 0014
14 30 0000
14 30 0005
14 30 OOlb
00010
WATER
TEMP
CENT
8.5
8.6
8.5
24.9
24.8
24.6
15.5
15.4
15.4
00300 OOC77 00094
DO TRANSP CNDUCTVY
SECCHI FIELD
MG/L INCHES M1CHOMHO
1C.2
10.6
8.0
8.0
8.0
9.4
9.2
9.4
120
60
48
334
334
332
544
544
544
368
368
369
11EPALES
3
00400
PH
SU
8.40
8.40
8.40
8.70
8.70
8.70
8.40
8.37
8.39
00410
T ALK
CAC03
MG/L
193
193
193
173
173
173
211
0018
00610
NH3-N
TOTAL
MG/L
0.050
0.040
0.030
0.030
0.040
0.020
1202
FEET OEPTH
00625
TOT KJEL
N
MG/L
1.100
1.000
1.000
1.300
1.300
1.200
00630
N02&N03
N-TOTAL
MG/L
0.110
0.100
0.090
0.020K
0.020K
0.020K
00671
PHOS-DIS
ORTHO
MG/L P
0.019
0.013
0.006
0.007
0.009
0.008
DATE TIME OEPTH
FROM OF
fU DAY FEET
74/04/23 10 35 0000
10 35 0005
10 35 0014
74/0 7/09 15 13 0000
74/09/23 14 30 0000
14 30 0005
14 30 0009
14 30 0015
D066S
JS-TUT
3/L P
0.033
U.042
0.034
0.040
0.042
32217
CHLRPHYL
A
UG/L
2.5
13.8
19.5
00031
INCDT LT
REMNING
PERCENT
'
1.0
).04b
K VALUE KNOWN TO BE
LESS THAN INDICATED
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