U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
PACIFIC NORTHWEST ENVIRONMENTAL RESEARCH LABORATORY
An Associate Laboratory of the
NATIONAL ENVIRONMENTAL RESEARCH CENTER - CORVAILIS, OREGON
and
NATIONAL ENVIRONMENTAL RESEARCH CENTER - LAS VEGAS, NEVADA
•&GPO 697.032
-------
REPORT
ON
SIX MILE LAKE
ST, LJDUIS COUNIY
MINNESOTA
EPA REGION V
WORKING PAPER No, 126
WITH THE COOPERATION OF THE
MINNESOTA POLLUTION CONTROL AGENCY
AND THE
MINNESOTA NATIONAL GUARD
DECEMBER, 1974
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1
CONTENTS
Page
Foreword ii
List of Minnesota Study Lakes iv, v
Lake and Drainage Area Map Vi
Sections
I. Conclusions i
II. Lake and Drainage Basin Characteristics 3
III. Lake Water Quality Sumary 4
[ V. Nutrient Loadings 7
V. Literature Reviewed 12
VI. Appendices 13
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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 [ g3l4(a,b)],
and water quality monitoring [ 5106 and 5305(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 Minnesota Pollution Control
Agency for professional involvement and to the Minnesota National
Guard for conducting the tributary sampling phase of the Survey.
Grant J. Merritt, Director of the Minnesota Pollution Control
Agency, John F. McGuire, Chief, and Joel G. Schilling, Biologist,
of the Section of Surface and Groundwater, Division of Water Quality,
provided invaluable lake documentation and counsel during the course
of the Survey; and the staff of the Section of Municipal Works, Divi-
sion of Water Quality, were most helpful in identifying point sources
and soliciting municipal participation in the Survey.
Major General Chester J. Moeglein, the Adjutant General of
Minnesota, and Project Officer Major Adrian Beltrand, who directed
the volunteer efforts of the Minnesota National Guardsmen, are also
gratefully acknowledged for their assistance to the Survey.
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iv
NATIONAL EUTROPHICATION SURVEY
STUDY LAKES
STATE OF MINNESOTA
LAKE NAME COUNTY
Albert Lea Freeborn
Andrusia Beltranii
Badger Polk
Bartlett Koochiching
Bear Freeborn
Bemidji Beltrami
Big Stearns
Big Stone Big Stone, MN; Roberts,
Grant, SD
Birch Cass
Bi ackduck Bel trami
Blackhoof Crow Wing
Budd Martin
Buffalo Wright
Calhoun Hennepin
Carlos Douglas
Carrigari Wright
Cass Beltrami, Cass
Clearwater Wright, Stearns
Cokato Wright
Cranberry Crow Wing
Darling Douglas
Elbow St. Louis
Embarass St. Louis
Fall Lake
Forest Washington
Green Kandiyohi
Gull Cass
Heron Jackson
Leech Cass
Le Homme Dieu Douglas
Lily Blue Earth
Little Grant
Lost St. Louis
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V
LAKE NAME COUNTY
Madison Blue Earth
Malmedal Pope
Mashkenode St. Louis
McQuade St. Louis
Minnetonka Hennepin
Minnewaska Pope
Mud Itasca
Nest Kandiyohi
Pelican St. Louis
Pepin Goodhue, Wabasha, MN;
Pierce, Pepin, WI
Rabbit Crow Wing
Sakatah Le Sueur
Shagawa St. Louis
Silver McLeod
Six Mile St. Louis
Spring Washington, Dakota
St. Croix Washington, MN; St. Croix,
Pierce, WI
St. Louis Bay St. Louis, MN; Douglas, WI
Superior Bay St. Louis, MN; Douglas, WI
Swan Itasca
Trace Todd
Trout Itasca
Wagonga Kandiyohi
Wailniark Chisago
White Bear Washington
Winona Douglas
Wolf Beltrami, Hubbard
Woodcock Kandlyohi
Zumbro Olmstead, Wabasha
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V
SIX MILE LAKE
Sewage Treatment Facility
Tributary Sampling Site
Lake Sampling Site
Direct Drainage Area Linii
Indirect Drainage Area
Th
Location
-------
SIX MILE LAKE
STORET NO. 2783
I. CONCLUSIONS
A. Trophic Condition:
Survey data show that Six Mile Lake is eutrophic. Of the
80 Minnesota lakes sampled in 1972, 46 had less mean total
phosphorus and mean dissolved phosphorus, all had greater mean
inorganic nitrogen (Six Mile Lake is known to have abundant
macrophytes), 38 lakes had less mean chlorophyll a , and 41
had greater Secchi disc transparency.
B. Rate-Limiting Nutrient:
An algal assay sample was not collected at Six Mile Lake.
However, the level of nutrients observed in Six Mile Lake indi-
cates that the potential primary productivity was high.
The lake data indicate nitrogen limitation at both samp-
ling times.
c. Nutrient Controllability:
1. Point sources-—The villages of Buhl and Fraser account
for almost 89% of the mean annual phosphorus load reaching Six
Mile Lake.
The present loading rate of phosphorus, 5.08 g/m 2 /yr, is
six times that proposed by Vollenweider (in press) as “dangerous”;
i.e., a eutrophic rate (see page 11). With complete phosphorus
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2
removal at the two point sources, the rate would be reduced
to 5.1 lbs/acre/year or 0.57 g/m 2 /yr. This would be a meso-
trophic loading rate and should result in improvement of the
trophic condition of Six Mile Lake.
2. Non-point sources—-The mean annual phosphorus contribution
from non-point sources was estimated to be 11.1%. The gaged tribu-
taries were estimated to contribute 10% while the ungaged drainage
areas were estimated to contribute less than 1%.
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II. LAKE AND DRAINAGE BASIN CHARACTERISTICS
A. Lake Morphometry :
1. Surface area: 84 acres.
2. Mean depth: 6.3 feet.
3. Maximum depth: 14 feet.
4. Volume: 529 acre/feet.
5. Mean hydraulic retention time: 36 days.
B. Tributary and Outlet:
(See Appendix A for flow data)
1. Tributaries -
Name Drainage area* Mean flow*
Unnamed Stream (B-l) 7.4 mi? 3.8 cfs
Unnamed Stream (C-l) 6.3 mi 3.2 cfs
Minor tributaries & 2
immediate drainage - 1.0 mi 0.5 cfs
Totals 14.7 mi2 7.5 cfs
2. Outlet -
Dempsey Creek 14.8 mi2** 7.5 cfs
C. Precipitation***:
1. Year of sampling: 28.0 inches.
2. Mean annual: 26.9 inches.
t DNR lake survey map (1968); mean depth by random-dot method.
* Drainage areas are accurate within ±5%; mean daily flows are accurate
within ±10%; and ungaged flows are accurate within ±10 to 25% for
drainage areas greater than 10 mi2.
** Includes area of lake.
*** See Working Paper No. 1, "Survey Methods.".
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4
Parameter
Temperature (Cent.)
Dissolved oxygen (mg/i)
Conducti vi ty (pmhos)
pH (units)
Alkalinity (mg/i)
Total P (mg/i)
Dissolved P (mg/i)
NO + NO (mg/i)
Arr onia mg/l)
Chlorophyll a (pg/i)
Secchi disc finches)
Mean Values
1st Sample
( 07/08/72 )
19.6
5.1
305
7.6
117
0.336
0.247
0.040
0.040
12.4
38
2nd Sample
( 09/09/ 72 )
15.4
11.6
320
8.9
131
0.155
0.103
0.055
0.065
29.5
36
III. LAKE WATER QUALITY SUMMARY
Six Mile Lake was sampled twice during the open—water season of 1972
by means of a pontoon-equipped Huey helicopter. Each time, samples for
physical and chemical parameters were collected from two depths at the
single station on the lake (see map, page vi). During each visit, a
depth-integrated (near bottom to surface) sample was collected for
phytoplankton identification and enumeration, and a similar sample was
collected for chlorophyll a analysis. The maximum depth sampled was 9
feet.
The results obtained are presented in full in Appendix B, and the
data are summarized below.
A. Physical and chemical characteristics:
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5
Mm. for Max. for Mean for
Parameter all samples all samples all samples
Temperature 15.4 20.4 18.2
Dissolved oxygen 2.2 11.6 7.3
Conductivity 290 320 313
pH 6.2 9.0 8.2
Alkalinity 110 132 124
Total P 0.130 0.384 0.246
Dissolved P 0.099 0.301 0.175
NO + NO 0.040 0.070 0.047
Arn onia 0.030 0.070 0.052
Chlorophyll a 12.4 29.5 209
Secchi disc 36 38 37
1 . Phytoplankton -
Sampling Dominant Number
Date Genera per ml
1. Cyclotella 8,855
2. Cryptomonas 1,446
3. Microcystis 723
4. Cocconeis 663
5. Kirchneriella 542
Other genera 3,072
Total 15,301
1. Anabaena 4,262
2. Stephanodiscus 1,698
3. Cryptomonas 1,321
4. Flagellates 1,094
5. Dinobryon 755
Other genera 1 ,034
B. Biological characteristics:
07/08/7 2
09/09/ 72
Total
10,164
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6
2. Chlorophyll a -
(Because of instrumentation problems during the 1972 sampling,
the following values may be in error by plus or minus 20 percent.)
Sampling Station Chlorophyll a
Date Number ( pg/i )
07/08/72 01 12.4
09/09/72 01 29.5
C. Limiting Nutrient Study:
Six Mile Lake was not sampled in the fall of 1972. Consequently,
an algal assay sample was not obtained. However, the level of nu-
trients in Six Mile Lake indicates that the potential primary pro-
ductivity was high.
The lake data indicate nitrogen limitation at both sampling
times; N/P ratios were about 1/1, and nitrogen limitation would
be expected.
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7
IV. NUTRIENT LOADINGS
(See Appendix C for data)
For the determination of nutrient loadings, the Minnesota National
Guard collected monthly near-surface grab samples from each of the tribu-
tary sites indicated on the map (page vi), except for the high runoff
months of April and May when two samples were collected. Sampling was
begun in October, 1972, and was completed in September, 1973.
Through an interagency agreement, stream flow estimates for the year
of sampling and a “normalized” or average year were provided by the
Minnesota District Office of the U.S. Geological Survey for the tributary
sites nearest the lake.
In this report, nutrient loads for sampled tributaries were determined
by using a modification of a U.S. Geological Survey computer program for
calculating stream loadings*. Nutrient loadings for unsampled “minor
tributaries and immediate drainage” (“ZZ” of U.S.G.S.) were estimated by
using the means of the nutrient loads, in lbs/mi 2 /yr, in Leech Lake
tributaries at stations C—i, D—i , F—l , G—l , H—i , and J—l and multiplying
the means by the ZZ area in mi 2 .
The villages of Buhi and Fraser did not participate in the Survey,
and nutrient loads were estimated at 2.5 lbs P and 7.5 lbs N/capita/year.
The measured nutrient loads at stations B-i and C—l were less than the
estimated wastewater treatment plant loads. Therefore, nutrient loads
were estimated in the same way as the ZZ loads. The full nutrient loads
* See Working Paper No. 1.
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8
from Buhi and Fraser wastewater treatment plants were assumed to have
reached the lake during the sampling year.
A. Waste Sources:
1. Known municipal* -
Pop. Mean Receiving
Name Served Treatment Flow (mgd) Water
Buhl 1,303 trickling 0.130** Buhi Creek to
filter Swan River
Fraser 48 primary 0.005** Creek to Six
Mile Lake
2. Known industrial - None
* Anonymous, 1974.
** Estimated at 100 gal/capita/day.
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9
B. Annual Total Phosphorus Loading - Average Year:
1. Inputs -
lbs Pf % of
Source yr total
a. Tributaries (non-point load) -
[ inflamed Stream (8-1) 210 5.5
Unnamed Stream (C-i) 180 4.7
b. Minor tributaries & immediate
drainage (non-point load) - 30 0.8
c. Known municipal STP’s -
Buhl 3,260 85.6
Fraser 120 3.1
d. Septic tanks - Unknown -
e. Known industrial - None
f. Direct precipitation* - 10 0.3
Total 3,810 100.0
2. Outputs -
Lake outlet - Dempsey Creek 1 ,690
3. Net annual P accumulation - 2,120 pounds
* See Working Paper No. 1.
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10
C. Annual Total Nitrogen Loading - Average Year:
1 . Inputs -
lbs NI % of
Source yr total
a. Tributaries (non-point load) -
Unnamed Stream (B-l) 9,260 31.6
Unnamed Stream (C-i) 7,880 26.9
b. Minor tributaries & immediate
drainage (non-point load) - 1,250 4.3
c. Known municipal STP’s -
Buhi 9,770 33.3
Fraser 360 1.2
d. Septic tanks - Unknown
e. Known industrial - None - -
f. Direct precipitation* - 810 2.7
Total 29,330 100.0
2. Outputs -
Lake outlet - Dempsey Creek 33,640
3. Net annual N loss - 4,310 pounds
* See Working Paper No. 1.
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11
D. Yearly Loading Rates:
In the following table, the existing phosphorus loading
rates are compared to those proposed by Vollenweider (in press).
Essentially, his “dangerous” rate is the rate at which the
receiving waters would become eutrophic or remain eutrophic; his
“permissible” rate is that which would result in the receiving
water remaining oligotrophic or becoming oligotrophic if mor-
phometry permitted. A mesotrophic rate would be considered one
between “dangerous” and “permissible”.
Total Phosphorus Total Nitrogen
Units Total Accumulated Total Accumulated
lbsJacr /yr 45.4 25.2 349.2 loss*
grams/rn /yr 5.08 2.83 39.1 -
Volle weider loading rates for phosphorus
(g/m /yr) based on mean depth and mean
hydraulic retention time of Six Mile Lake:
“Dangerous” (eutrophic rate) 0.84
“Permissible” (oligotrophic rate) 0.42
* There was an apparent loss of nitrogen during the sampling year. This may
have been due to nitrogen fixation in the lake, solubilization of previously
sedimented nitrogen, recharge with nitrogen-rich ground water, unknown and
unsampled point sources discharging directly to the lake 1 or underestimation
of the nitrogen loads from the villages of Buhi and Fraser. Whatever the
cause, a similar nitrogen loss has occurred at Shagawa Lake, Minnesota, which
has been intensively studied by EPA’s National Eutrophication Research and
Lake Restoration Branch.
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12
V. LITERATURE REVIEWED
Anonymous, 1974. Wastewater disposal facilities inventory. MPCA,
Minneapolis.
Miller, Richard D., and C. A. Johannas, 1960. Report on follow-up
investigation of Six Mile Lake and tributaries, Stuntz Township
St. Louis County. MN Dept. of Health, Minneapolis.
Schilling, Joel, 1974. Personal communication (lake map). MPCA,
Minneapolis.
Vollenweider, Richard A., (in press). Input-output models. Schweiz
A. Hydrol.
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13
VII. APPENDICES
APPENDIX A
TRIBUTARY FLOW DATA
-------
TRIBuTARY FLOW INFORMATION FOR MINNESOTA
10/30/74
LAKE CODE ?7R3
SIXHILE LAKE
TOTAL ORAINAC.E AREA OF LAKE
14 • 80
TOTAL DR. INAGE AREA OF LAKE =
SliM OF SUB—OPA IP 1A6E AREAS =
TRIRUTAPY MONTI-4
YEAR “lEAN FLOW DAY
FLOW DAY FLOW DAY
FLOW
SUP—DRA INAC,E
TRIBuTARY ARFA
2783A 1
278381
?781C I
27R 1Z 7
14.80
7.41
6.31
1 .08
JAN FEB MAP APP MAY
0.43
0.21
0.18
0.02
0.39
0.19
0 • 15
0.0!
1 .49
0.71
0.71
0.11
NORMALIZED FLOWS
JuN JUL AUG
36.81
18.30
15.40
2.37
18.75
9.75
7.95
1.23
10.25
5.30
4.52
0.79
8.00
4.20
3.41
0.54
MEAN MONTHLY FLOWS AND DAILY FLOWS
2.25
1.19
0.89
0.12
SEP OCT NOV DEC MEAN
3.20
1.78
1 .40
0.23
SUMMARY
4.64
2.50
1.84
0.24
3.02
1.58
1 • 15
0.13
0.72
0.38
0.30
0.04
14.80
TOTAL
FLOW
IN
89.82
14.80
TOTAL
FLOW
OUT
=
99.95
7 • 49
3.84
3.16
0.49
278 1A1
10
72
2.96
15
2.90
11
72
I.S5
16
1.50
1?
72
0.48
18
0.50
1
73
0.36
14
0.30
2
73
0.40
18
0.40
1
73
3.27
16
5.60
4
73
8.28
4
4.60
5
71
14.f,0
6
13.00
6
73
7.46
lB
8.80
7
73
1.61)
17
2.20
1)
73
4.42
21
6.80
9
73
1.94
14
1.60
279391
10
II
17
1
2
1
4
5
6
7
8
9
7 ’
72
12
73
73
73
71
73
71
71
7•3
71
I.c6
0.79
j.2 5
0.17
0.19
1.57
4.1)1
7.41
1.76
1.86
?.
1. S
15
if,
18
14
18
16
6
‘
18
17
21
14
1.50
0.80
0.20
0.20
0.20
2.60
2.?0
4.40
1.10
3.50
0.84
24
21
24
21
16.00
5.30
8.00
2.70
-------
T4TBUT PY FLOw 1NFO M4T1ON FOP IINNESOTA
10/30/74
LA’(F CODE 77 3
S!XMILE LAKE
MEAN MONTHLY FLOWS N [ ) tiAILY FLOWS
10
11
FLOW
TP1 IJTARY MONTt-4 ‘EAP MEAN FLOW O Y FLOW DAY
FLOW DAY
?7 1C 1
24
21
6.70
2.20
27R3Z2
24
21
1.00
0.30
7
1.15
15
1.10
7?
0.
16
0.60
72
0.20
I
0.20
73
0.15
14
0.10
73
0.15
18
0.10
1
71
1.52
16
2.60
4
71
3 .3Q
6
1.90
5
7
6.)4
6
5.20
6
73
3.’l
18
3.PQ
7
71
1. 0
17
0.92
7
1.71
21
2.60
9
73
0•Q3
14
0 ,66
10
7.
o.is
is
0.?0
Ii
77
0.P6
1
C.06
J7
72
0.0’
1’4
0.02
1
73
0.02
14
0.02
2
71
fl.uI
1F
0.01
1
73
) 74
if,
0.40
4
73
0.5?
6
0.30
5
71
0.93
6
0.80
6
71
0.56
18
0.70
7
71
0.?4
ii
(.15
7_3
Q•23
21
0.35
9
‘3
0.14
14
0.11
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APPENDIX B
PHYSICAL and CHEMICAL DATA
-------
STOPET ETPlEVAL DATE 74/10/30
DATE
FR OH
TO
TIME DE TH
OF
DAY FEET
3’?17
CHL °HYL
A
Ii G/L
12.4J
29 • 5J
278301
47 26 55.0 092 48 37.0
SIXMILE LAKE
27 MINNESOTA
DATE
F POM
TO
TIME DEPTH
OF
DAY FEET
00010
WATER
TEMP
CENT
?0.4
I 8.R
77/07/OR 1 70 0000
12 20 0009
77/09/09 13 30 0000
13 30 0005
00300 00077
DO TRANSP
SE CCH I
MG/L INCHES
38
36
11.6
1 IEPALES
2111202
3
0009 FEET DEPTH
00094
CF4DUC TV Y
FIELD
MICROMMO
290
320
320
320
00400
00410
00630
00610
00665
00666
PH
T ALK
CACO3
N02&N03
N—TOTAL
P1H3-N
TOTAL
P i0S—T0T
PHOS—DIS
Sli
MG/L
MG/L
MG/L
MG/L P
MG/L P
9.00
6.20
8.90
8.90
110 0.040
123 0.040
130 0.040
132 0.070
7?/07/OR 1? 20 0000
7?/OQ/09 13 30 0000
0.0 30
0.050
0.0 60
0.070
0.289
0.384
0.181
0.130
0 • 194
0.30 1
0.108
0.099
J V L? rc’li) JN 1) , E PJ
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APPENDIX C
TRIBUTARY DATA
-------
cTDRF:T ETPT vAL 74/10/ 0
?N3A I LS?783A1
‘+7 27 30.0 09? 48 00.0
DE 1PS Y CREEK
77 7.5 HUHL
0/SIAMILE LAKE
CO HWY 42 NE 6 MILE LAKE 2.5
I1EPALES 2111204
4 0000 FEET
t 0’-3
006 7
(J0 610
00671
00665
DAIF
T1• 1-
flE T-j
J? NO3
[ UT KJ L
i’irl 3—N
PF-i115—1)IS
PHOS—TOT
FR3M
)F
J—T )TAL
N
TOFAL
ORTHO
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i)AY
Ff T
M(/L
11,/I
Mfl/L
MG/L P
MG/L P
7?/1fl/l
q
00
0.07?
0.013
0.060
7?/il/1”
l
(‘0
u.0 7 ’
. ‘)0
0.031
U. O O SPc
0.031
73/04/06
09
75
rb.01
3.1O )
0.044
0.02k
U.140
71/04/?’.
25
(,.(fl 7
2.(4 0(,
).075
0.015
0.105
73/05/06
lB
5
U. JI-
‘.‘OO
C .06M
0.023
0.050
71/05/? )
l
‘5
i.0’ -’
3.1w
‘.0 ()
0.05
0.0 5
71/0# /I-
0 4
?fl
•( .-i
C_ i
0.05?
0.110
0.150
73/07/17
)Q
79
• )7
7 . fl(
0.050
0.115
0.175
71/08/?)
19
‘
.‘7 0
4.300
0.170
A.’52
0.280
73/09/ I -.
1
‘0
O. ’ l)
3. 00
0.210
0.160
0.200
MI SSW BrIL
DEPTH
K VALUE KNOWN TO BE LESS
Te-1 N INDIC TEf)
-------
STORE ?ErpTevAI DafE 14/I’ / ()
27 Jb1
47 ?7 00.0 09? 49
UP JAMED T Ii TO ‘,
1.’:, t3UHL
I/SIXt4ILE LAKE
ST Ht Y S r DG .5
I IEPALFS
4
LS27M3E 1
30 • 0
‘IILE LAKE
M N OF WILPEN
2111204
0000 FEET DEPTH
iO&’
1 1G
0(;671
006b5
)AT
TP F
rW1 1 I
•) NO.4
TC’T P ‘FL
‘IH1— J
PhOS— HS
os—Tor
F ’OM
Or
1—tOTAL
N
T )T4L
OPTrlO
TO
OAY
F T
i’,,L
‘ c ,L
HG/L
M( /L
MG/L P
72/I0/1
fl%
30
t.•4 ’
0.41)0
o.i c
0.0 0 5K
u. 019
72/fl/1 ’
12
40
C.’- . e0
).07 s
0.005K
0.021
73/04/0 ’
09
10
“.‘3’;
‘.?OO
fl.11 )
0.00’,
0.040
71f0 i/?4
U
05
“. “4
l.’ 0C
0 .3
0.005K
0.040
71/05/0’,
I’
()
•03’
3 .( fl ’
fl.0b9
0.0’?
0.100
71/05/21
1
1’)
3.01
0. 0
i.t,?4
0.012
0.020
73/0’,/
09
10
0.0’ ’
j., v)
0.044
0.02?
0.075
73/’ 7/1
1
10
u.0’
‘ ).U30
0.011
0.050
73/0 /?i
19
10
3.UYJ
0.’ )
0.07?
0.01?
0.045
71/0 /1 ’
10
10
.1l0
0.019
K VALUE KNOWN TO I E LESS
T’-s N INDICATED
-------
STOPET ‘QET’ I VAI 1). Tc 76/1L O
27M3B? LS27R3H2
47 2R 00.0 09? 50 00.0
UNNAME’) T It3 W SIDE 6 MILE LAKE
27 7.5 BUI-iL
T/SIXM!LE LA
AING E ST CLAIRE JCT/W Co t-1WY5 JCT BLSTP
1IFPALES 2111204
4 0000 FEET DEPTH
0?f 3
006
0) - 0
00671
00665
)ATE
T T’
flE ’-’TH
t’aO?V’Jfl
TOT fcJFL
Nrl 3—N
I-’hOS—I)IS
PHUS—TOT
FQ OM
“i—roT L
N
TOTAL
OPTHO
I C)
1)AY
FcFT
MC,/
lC./L
M( /L
M ,/L P
MG/L I
7?/1U/1 S
0.
IS
.•7- )
U. 50
0.105
0.0051<
0.013
7?/fl/I
I?
0
0. ’-,I
0.’- u
•i. 154
0.0P5
0.037
7 /0’ /06
09
00
I).2
I. 01
0.110
0.015
73/O- +/2
37
SS
(‘.i l
3.460
3.16E 1
0.007
(‘.045
73/05/0k
1
)
).03
2 Q4 ,J
0.01
0.035
7 /0S/?I
I’
oo
C.0 3
3.9 C M )
0.063
0.0?0
0.060
7 /0 /1
00
( 0
‘.0 B
) . 40
1. ohc
0.026
0. OB S
7 /07/17
19
00
i.C Sr
.1”0
O.06 -
0.110
73/OP/?I
19
00
‘i.0 7
1. 00
‘.C7’
0. 1 )72
0.055
71/3’4/ 14
19
00
.031
‘ .135
0.017
0.055
VALUE i N0WN TO d LESS
THAN I L)IC/ 1 EO
-------
STDPET ETt?1.VAL JATI +/ •/ O
?7 3C1 LS27 33C1
47 ‘7 00.0 092 48 30.0
U”JNAMEII ST. FM SW RWIL 10 6 MILE
27 7.5 BUHL
T/SI*MILE LAIQ
CO -IwY 64 XIN( N SMILE LK t3ELW 9UHL SIP
1 IEPALES 2111204
4 0000 FEET DEPTH
nY3 ‘ 0’10 0fl571 006 55
)ATF T 1M E O Tr ’ ‘ ‘17M’() tOT KjH NH3—N Pb-IOS—i)IS PHOS—TOT
(W J—T )1 M N T )T4( ORTriO
TO ‘ Y F’- T 4(,/I ( ,/L M(,/L MC,/L P
72/l0/ISC- e5 I.(j -i .i.?flO ).354 0.013 0.344
73/04/0” ) ‘0 . - ‘) 7.1’7) !).?rC 0.0 ? 0. 220
71/OL./?4 ‘h ! ‘ .f5 ) Ø•077 0.0 ’0 U.13( ,
71/0S/0’ N 4 •).“.O 3.00 0.125 0.1R O
73/05/?l N .01J s U.’ ’ 0 ‘ .07? 0.750 0.31’)
71/Oh/N OQ ic ‘).46 1. 70 0.180 0.410 ( ‘.575
71/07/17 1 N .iIj J•Pfl9 0.053 0.’OO 0.240
73/0 /7l 19 l 1. 90 0.063 0.112
71/0 /1 4 LY 15 1.4 3.— ) O. 13’ 0.210 0. 0
K V’ LLJE KNOWN TO HE LESS
TrIAN INDICATE!)
------- |