U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
BLACKDUCK LAKE
BELTRAMI COUNTY
MINNESOTA
EPA REGION V
WORKING PAPER No, 86
PACIFIC NORTHWEST ENVIRONMENTAL RESEARCH LABORATORY
An Associate Laboratory of the
NATIONAL ENVIRONMENTAL RESEARCH CENTER • CORVALLIS, OREGON
and
NATIONAL ENVIRONMENTAL RESEARCH CENTER - LAS VEGAS, NEVADA
& GPO—697.032
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REPORT
ON
BLACKDUCK LAKE
BELTRAMI COUNTY
MINNESOTA
EPA REGION V
WORKING PAPER No, J
WITH THE COOPERATION OF THE
MINNESOTA POLLUTION CONTROL AGENCY
AND THE
MINNESOTA NATIONAL GUARD
NOVEMBER, 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 1
II. Lake and Drainage Basin Characteristics 3
III. Lake Water Quality Summary 4
IV. Nutrient Loadings 9
V. Literature Reviewed 13
VI. Appendices 14
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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 [ 5303(e)], water
quality criteria/standards review [ 5303(c)], clean lakes [ 5314(a,b)],
and water quality monitoring [ 5106 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.
AC KNOWLEDGMENT
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 Beltrami
Badger Polk
Bartlett Koochiching
Bear Freeborn
Bemidji Beltrami
Big Stearns
Big Stone Big Stone, uN; Roberts,
Grant, SD
Birch Cass
Blackduck Beltrami
Blackhoof Crow Wing
Budd Martin
Buffalo Wright
Calhoun Henrepin
Carlos Douglas
Carrigan Wright
Cass Beltrami, Cass
Clearwater Wright, Stearns
Cokato Wright
Cranberry Crow Wing
Darling Douglas
Elbow St 0 Louis
Embarass St. Louis
Fall Lake
Forest Washington
Green Kandiyohi
Gull Cass
Heron Jackson
Leech Cass
Le Home 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 Kandlyohi
Pelican St 0 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
Walimark Chisago
White Bear Washington
Winona Douglas
Wolf Beltrami, Hubbard
Woodcock Kandiyohi
Zumbro Olmstead, Wabasha
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Minnesota-
• Tribtitary
0
BLACKDUCK LAKE
Sampling Site x lake Sampling Site
Sewage Treatment Facility
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BLACKDUCK LAKE
STORET NO. 2711
I. CONCLUSIONS
A. Trophic Condition:
Survey data indicate Blackduck Lake is eutrophic. Of the
60 Minnesota lakes sampled in the fall when essentially all were
well—mixed, 22 had less mean total phosphorus, and 29 had less
mean inorganic nitrogen. For the 80 lakes studied, 32% had
greater Secchi disc transparency, and 50% had less mean chloro-
phyll a. Some depression of dissolved oxygen with depth was
noted at station 1 in July, 1972.
Survey limnologists observed an algal bloom in progress in
September, 1972. Reportedly, a permit was issued for the mechani-
cal removal of aquatic plants in a small area of the lake in 1971
(Bonnema and Johnson, 1972).
B. Rate—Limiting Nutrient:
The results of the algal assay show that the sample was
phosphorus limited. However, some change in nutrients from
lake to assay occurred, and it is possible the lake was nitro-
gen limited at the time the assay sample was collected (N/P
ratio = 13/1).
The lake data indicate nitrogen limitation at the other
sampling times (N/P ratios were less than 8/1).
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2
C. Nutrient Controllability:
During the sampling year, it is estimated that Blackduck
Lake received a total phosphorus load a rate less than that
proposed by Vollenweider (in press) as “dangerous”; i.e., a
eutrophic rate (see page 13) but more than a “permissible”
(oligotrophic) rate. Of this load, it is estimated that the
Village of Blackduck contributed about 42%. However, because
of the estimations and assumptions necessary in the assessment
of point and non—point loadings and loading rates, it is con-
cluded that further studies are needed to determine nutrient
controllability.
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3
II. LAKE AND DRAINAGE BASIN CHARACTERISTICS
A. Lake Morphometry*:
1. Surface area: 2,742 acres.
2. Mean depth: 14.8 feet.
3. Maximum depth: 28 feet.
4. Volume: 40,582 acre/feet.
5. Mean hydraulic retention time: 4.2 years.
B. Tributary and Outlet:
(See Appendix A for flow data)
1. Tributaries -
Name Drainage areat Mean flowt
Coburn Creek 4.5 mi 2 1.9 cfs
Crandall Lake outlet 4.6 mi 2 2.2 cfs
Minor tributaries & 2
immediate drainage - 15.6 mi 9.2 cfs
Totals 24.7 mi 2 13.3 cfs
2. Outlet -
Blackduck River 29.0 mi 2 tT 13.3 cfs
C. Precipitationttt:
1. Year of sampling: 26.7 inches.
2. Mean annual: 25.3 inches.
* DNR lake survey map (1949); mean depth by random-dot method.
t Drainage areas are accurate within ±5%; mean daily flows are accurate
within ±10%; and ungaged flows ar accurate within ±10 to 25% for
drainage areas greater than 10 mit.
tt Includes are of lake.
ttt See Working Paper No. 1, “Survey Methods”.
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4
III. LAKE WATER QUALITY SUMMARY
Blackduck Lake was sampled three times 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
stations on the lake and from a number of depths at each station (see
map, page vi). During each visit, a single depth—integrated (near
bottom to surface) sample was composited from the stations for phyto—
plankton identification and enumeration; and during the last visit, a
single five-gallon depth-integrated sample was composited from the
two stations for algal assays. Also each time, a depth-integrated
sample was collected from each of the stations for chlorophyll a analy-
sis. The maximum depths sampled were 15 feet at station 1, and 15 feet
at station 2.
The results obtained are presented in full in Appendix B, and the
data for the fall sampling period, when the lake was essentially well—
mixed, are summarized below. Note, however, the Secchi disc summary
is based on all values.
For differences in the various parameters at the other sampling
times, refer to Appendix B.
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5
A. Physical and chemical characteristics:
FALL VALUES
(10/21/72)
Parameter Minimum Mean Median Maximum
Temperature (Cent.) 4.3 4.3 4.3 4.4
Dissolved oxygen (mg/i) 10.4 11.0 11.2 11.2
Conductivity (pmhos) 240 240 240 240
pH (units) 7.8 7.9 7.9 7.9
Alkalinity (mg/i) 121 124 125 127
Total P (mg/l) 0.023 0.043 0.038 0.090
Dissolved P (mg/l) 0.009 0.016 0.013 0.025
NO + NO (mg/i) 0.150 0.160 0.160 0.170
Am onia mg/1) 0.040 0.053 0.050 0.070
ALL VALUES
Secchi disc (inches) 36 68 72 91
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6
B. Biological characteristics:
10 Phytoplankton —
Sampling Dominant Number
Date Genera per ml
07/12/72 1. Melosira 989
2. Dinobryon 989
3. Fragilaria 314
4. Cryptomonas 253
5. Microcystls 157
Other genera 555
Total 3,257
09/08/72 1. Anabaena 1,120
2. Microcystis 590
3. Lyngbya 277
4. Flagellates 265
5. Chroococcus 241
Other genera 748
Total 3,241
10/21/72 1. Dinobryon 2,997
2. Flagellates 708
3. Cryptomonas 648
4. rlelosira 151
5. Navicula 105
Other genera 524
Total 5,151
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7
2 Chlorophyll a —
(Because of instrumentation problems during the 1972 sampling,
the following values may be in error by plus or minus 20
percent.)
Sampl ing
Date __________ _______________
07/12/72
09/08/72 01
02
10/21/72 01
02
Maximum yield
____________ _________ - . ( mg/i—dry wt. )
2;1
4.6
6.4
7.2
7.8
26.5
2.6
Station
Number
01
02
Chlorophyll a
(pg/i)
10.1
14.1
9.8
28.7
14.0
10.6
C. Limiting Nutrient Study:
1. Autoclaved, filtered, and nutrient spiked —
Ortho P Inorganic N
Spike (mg/i) Conc. (mqll) Conc. (mg/l ) _____________
Control 0.016 0.272
0.005 p 0.021 0.272
o.oio P 0.026 0.272
0.020 p 0.036 0.272
0.050 P 0.066 0.272
0.050 P + 10.0 N 0.066 10.272
l0 0 N 0.016 10.272
2. Discussion —
The control yield of the assay alga, Selenastrum capri-
cornutum , indicates that the potential primary productivity
of Blackduck Lake was moderate at the time the sample was
taken. Increased yields with increasing increments of phos-
phorus, and the lack of a significant increase in yield when
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8
nitrogen only was added, indicates that phosphorus was lim-
iting in the assay sample.
The lake data indicate nitrogen limitation in July (N/P
ratio = 4/1) and September (N/P ratio = 7/1) but a borderline
N/P ratio of 13/1 in October.
It is noted that there was about a 60 pg/i gain in inor-
ganic nitrogen between sampling and the beginning of the
assay. Had this change not occurred, the assay sample prob-
ably would have been nitrogen limited.
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9
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
month of April when two samples were collected, and the colder months
when low flows prevented sampling at station A-i. 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 unormaiizedfl 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 calculated
using mean concentrations and mean flows, except for Coburn Creek at station
B—i where nutrient concentrations in at least 5 of the 13 samples were so
high that it appears that most if not all of the stream flow at those times
must have been effluent from the Village of Blackduck wastewater treatment
plant (see station 2711B—l in Appendix C). Accordingly, the nutrient
loads attributed to Coburn Creek were estimated as follows. The total
phosphorus load measured at the Crandall Lake outlet (C-i) amounted to
57 lbs P per square mile of drainage area for the sampling year. Now,
the drainage area and flows of Coburn Creek are almost identical to those
of the Crandall Lake outlet. Assuming the non—point nutrient sources in
the two drainages are also similar, and assuming that 50% of the P load
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10
of the drainage was sedimented and/or biologically assimilated in Crandall
Lake, it is estimated that the non-point source load in Coburn Creek was
2 x 57 lbs/mi 2 /yr or 114 lbs P/mi 2 for the sampling year (4.5 mi 2 x 114 =
513 ibs). Nitrogen was similarly estimated, but rio loss was assumed in
Crandall Lake.
Nutrient loadings for “minor tributaries and immediate drainage”
(“ZZ” of U.S.G.S.) were estimated by using the mean concentrations in
the Crandall Lake outlet at station C—i and ZZ flows.
The Village of Blackduck declined participation in the Survey, and
nutrient loads were estimated at 2.5 lbs P and 7.5 lbs N/capita/year.
A. Waste Sources:
1. Known municipal —
Pop. Mean Receiving
Name Served Treatment Flow (mgd) Water
Blackduck 595* Trickling 0.060** Blackduck Lake
filter
2. Known industrial — None
* Anonymous, 1973.
** Estimated at 100 gal/capita/day 0
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11
B. Annual Total Phosphorus Loading — Average Year:
1. Inputs —
lbs P1 % of
Source yr total
a. Tributaries (non—point load) -
Coburn Creek 510 14.5
Crandall Lake outlet 260 7.4
b. Minor tributaries & immediate
drainage (non-point load) - 820 23.4
c. Known municipal —
Blackduck 1,490 42.5
de Septic tanks — Unknown —
e. Known industrial — None — —
f. Direct precipitation* - 430 12.2
Total 3,510 100.0
2. Outputs —
Lake outlet — Blackduck River 1,580
3. Net annual P accumulation — 1,930 pounds
* See Working Paper No. 1.
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12
C. Annual Total Nitrogen Loading - Average Year:
1. Inputs —
lbs NI % of
Source yr total
a. Tributaries (non—point load) —
Coburn Creek 6,440 10.0
Crandall Lake outlet 6,580 10.2
b. Minor tributaries & immediate
drainage (non—point load) - 20,820 32.2
c. Known municipal -
Blackduck 4,460 6.9
d. Septic tanks — Unknown - —
e. Known industrial — None — -
f. Direct precipitation* — 26,420 40.8
Total 64,720 100.0
2. Outputs —
Lake outlet — Blackduck River 35,480
3. Net annual N accumulation — 29,240 pounds
* See Working Paper No. 1.
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13
D , Mean Annual Non—point Nutrient Export by Subdrainage Area:
Tributary lbs P/mi 2 /yr lbs N/mi 2 /yr
Crandall Lake outlet 57 1,430
E. 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 oligo—
trophic if morphometry permitted. A mesotrophic rate would
be considered one between “dangerous” and “permissible”.
Total Phosphorus Total Nitrogen
Units Total Accumulated Total Accumulated
lbs/acre/yr 1.3 0.7 23.6 10.7
grams/m 2 /yr 0 14 0.08 2.6 1.2
Vollenweider loading rates for phosphorus
(g/m 2 /yr) based on mean depth and mean
hydraulic retention tine of Blackduck Lake:
“Dangerous” (eutrophic rate) 0 20
“Permissible” (oligotrophic rate) 0.10
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14
V. LITERATURE REVIEWED
Anonymous, 1973. Wastewater disposal facilities inventory. F 1PCA,
Minneapolis.
Bonnema, Kenneth, and William 6. Johnson, 1972. Control of aquatic
vegetation, algae, leeches, and swimer’s itch in 1971. Dept.
Nat. Resources, Minneapolis.
Schilling, Joel, 1974. Personal communication (lake map). r 1PCA,
Minneapolis.
Vollenweider, Richard A., (in press). Input—output models. Schweiz.
A. Hydrol.
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15
VII. APPENDICES
APPENDIX A
TRIBUTARY FLOW DATA
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TRIBUTAPY FLOW INFORMATION FOP MINNESOTA 10/30/74
LA (F CODE 2711 BLACKOUCK LAKE
TOTAL )RAINAGE AREA OF LAKE ‘9.00
S IJ B—DRAINASE NORMALIZED FLOWS
TRIBUTARY AREA JAN FEB MAR APR HAY JUN JUL AUG SEP OCT NOV DEC MEAN
27 11A1 29.00 3.21 2.08 5.31 34.40 37.40 28.10 13.80 6.62 11.40 7.84 5.30 4.78 13.38
271181 4.48 0.31 0.16 0.91 6.29 5.09 4.44 1.90 0.67 1.54 0.80 0.48 0.49 1.92
27 ! ICI 4.64 0.69 0.39 1.05 5.07 6.05 4.59 2.29 1.06 2.11 1.30 0.81 0.97 2.20
27 hZ? 19.90 3.90 2.21 5.20 22.60 24.10 19.50 8.97 4.05 7.48 4.88 3.19 4.18 9.19
SUMMARY
TOTAL DPAINAGI AREA OF LAKE = 29.00 TOTAL FLOW IN 159.57
SUM OF SUt —DRA1NAGE AREAS = 29.02 TOTAL FLOW OUT = 160.24
MEAN MONTHLY FLOWS AND DAILY FLOWS
TPH4UTAPY ‘4ONT’l YEAR MEAN FLOW )AY FLOW DAY FLOW DAY FLOW
?7 1 1A1 10 72 7.19 14 9.50
11 7? 5.00 5 5.00
1 7? 7.19 10 7.00
1 73 3.53 20 3.10
73 2. 3 IN 2.20
3 73 16.50 17 44.00
4 73 4. 2 1 13.00 14 1.70
5 73 6.M6 19 9.70
6 73 3.37 3 4.70
7 73 2.6? 8 1.00
R 73 3.57 11 6.70
9 73 79.10 lb 49.00
271181 10 7? 0.71 14 1.00
I I 72 0.46 5 0.50
12 7? 0.74 10 0.70
73 0.’4 20 0.30
7 73 0.17 18 0.20
3 73 7.48 17 7.50
4 73 0.88 1 2.40 0.30
c 73 0. 6 1 1.30
6 73 0.53 3 0.70
7 73 O.3h 8 0.41
8 73 1.37 11 2.60
9 73 10.50 16 6.50
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Ti Jr4IjjAr Y FLOW ENFOPMAT ION FO 4INNESOLA
10/30/74
LA
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APPENDIX B
PHYSICAL and CHEMICAL DATA
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STORET RETRIEVAL DATE 74/10/JO
271101
47 44 20.0 094 37 45.0
BLACKDUCI( L*I E
27 MINNESOTA
1 IEPALES
4
2111202
0014 FEET DEPTH
DATE
F P OM
TO
72/07/12
72/0 /0R
72/10/21
TIME DEPT’-t
OF
DAY FEET
13 35 0000
13 55 0000
16 10 0000
3?21 7
CHLRPHYL
A
IJG/L
00010
00300
00077
00094
00400
00410
00630
00610
10665
00666
DATE
TIME
DEPTH
WATER
DO
TRANSP
CNDUCTVY
PH
T ALK
N02&N03
NH3—Pd
PHOS—TOT
PHOS—DIS
FROM
OF
TEMP
SECCHI
FIELD
CACO3
N—TOTAL
TOTAL
TO
DAY
FEET
CENT
MG/L
INCHES
MICRONHO
Su
MG/L
MG/I
MG/I
P4/L P
MG/L P
72/07/12
13 35 0000
72
13 35 0004
22.7
10.2
260
7.20
130
0.030
0.050
0.025
0.015
13 35 0015
21.1
6.4
260
7.40
131
0.030
0.050
0.034
0.024
72/09/08
13 55 0000
16.8
60
243
8.15
128
0.140
0.100
0.049
0.023
13 55 0004
16.5
6.3
242
8.23
128
0.140
0.080
0.043
0.019
13 55 0010
16.3
6.6
242
8.23
129
0.140
0.070
0.046
0.016
72/10/21
16 10 0000
91
240
7.90
125
0.150
0.050
0.023
0.009
16 10 0004
4.3
11.2
240
7.90
123
0.150
0.040
0.025
0.012
16 10 0015
4.3
11.2
240
7.90
121
0.160
0.070
0.090
0.014
10. 1J
9.RJ
!4. (Li
J VALUE KNOWN TO BE IN ERROR
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STORET RETRIEVAL DATE 74/1J/30
271102
47 43 30.0 094 36 00.0
BLACKOUCK LAKE
27 MINNESOTA
1 1EPALES
4
0 )!) 10
WATFR
TEMP
CENT
2111202
0015 FEET DEPTH
00400 00410
TALK
CACO3
SI) MG/L
00300 00077
DO T4ANSP
SECCMI
MG/L INCI-4ES
7?
6.4
R 2
36
10.6
1f• . 1
75
10.4
11. ’
00094
CNDIJCTVY
FIELD
MICWOMHO
245
250
240
240
240
240
240
240
DATE
TIME OFPTH
FROM
OF
TO
041 FEET
7?/07/1?
13 55 0000
13 55 0004
13 55 0015
?l.7
‘1.5
7?/09/OR
14 10 0000
14 10 0004
14 10 0010
17.3
17.1
1b.
72/10/21
16 30 0000
1 ’ 30 00 4
16 30 000f
4.
4.4
DATF
TIME r TH
3 ?1 7
CPIL PHYL
F 0M
OF
A
TO
DAY FEET
I C,/L
7?/07/1?
11 55 0O0
1”.1J
72/09/OR
14 JO ijMO
.7J
72/10/21
16 10 MOO
10. J
00665 00666
PHOS—TOT PHOS—DIS
MG/L P MG/L P
00630
N02 .NO3
N-TOTAL
MG/I
0.040
a.030
0.060
0.060
0.060
0.170
0.170
0.160
7.70
7.60
8.70
8.70
8.65
7.80
7.80
7.90
00610
NH3-W
TOT AL
MG/I
0.060
0.040
0.080
0.080
0.0 70
0.060
0.050
0.050
130
130
128
128
129
125
125
127
0.042
0.043
0.085
0 • 096
0.086
0.036
0.047
0 • 040
0.019
0.020
0 • 034
0.0 31
0 • 030
0.013
0.025
0.022
J VALUE KNOWN TO BE IN ERROR
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APPENDIX C
TRIBUTARY DATA
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sTD FT ?FT J VoI. iAt 7’/1 ’j/ O
?F IIAI L’?71 1A 1
(47 4C5 30.0 )Q 4 3’ 00.0
t LACr )&jC’< kIV-
C ) * , ‘ iEET $I
(J/-4LACKDUCK LAKE
CO I- Y 37 R DG 2.5 MI NW Of i LACKDUCK
1FPALFS 2111204
4 0000 FEET DEPTH
01j611 O36f.
DATF T1 ’ 1)E ’T-l ) ti) 3 lOT J’L ‘‘-11—N °rlOS—flIS -‘HOS—TOT
OF ‘—T( TAj TOTAL UPTi()
F ) OAY FFP T ‘/L W,/L /L P MG/L
72/fl/OS 11 nc O.7’ ’ ‘.035 0.0
71/)1/I7 LI 75 l. ”f’ J, 054 ¶ 1.011 ).0S’)
71/04/01 0.33 0.013 0.115
71/04/14 II 74) .0I J’ ‘).072 3.ril SK fl.o35
73/05/34 I? 75 .O1j’ ‘i.PlO 0.C1 ’ ( .)O
71/C’ /03 11 45 • .0I ’ 1.r5i 1.014 0.017 0.077
73/07/0J 13 20 0. ’ O ).05c 0.0 .M 0.070
71/nR/1I 11 I1 .fl3-, I. 0C O.( ’?f’ 0.0?2 u.0 o
71/09/1 ’- 1’ 1 ’ .CS’ ‘J. OIQ 0.0 ,S
pc VALUE ‘KNOwN TO BE LESS
Tri(N I’ JOICATFJ)
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47 43 00.0 094 35 30.0
CR NDALL/ LACf(OUCK LAKES COMM
27 CO #4 SHEET #1
T/ LACKOUCK LAIKE
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2111204
0000 FEET DEPTH
(,0 1J
00675
J0610
00671
00665
r iTE
T1 F
DF ’TM
N ’ NOI
Tt)T K WL
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OF
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N
TOTAL
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TO
flAY
F T
uc/L
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MG/I
P G/L P
M6/L ‘.‘
7?/10/14
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00
1.104
0.075
0.005K
0.O”f,
7?/1I/0S
16
17
0.017
0.056
0.005K
0.011
72 J?/L0
14
00
3.130
1.760
.076
9.007
0.040
71 91/?0
1
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1. 00
0.205
Q•Q37
0.065
73/0.?/l?
15
20
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1.760
0.220
0.039
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73/01/17
1’
57
1.600
0.115
0. O1R
0.050
73/04/01
16
35
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l.43(
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0.006
0.045
73/ )4/16
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15
0.017
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ti.019
0.006
0.015
73/ 5/I
13
20
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0.075
0.090
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1.101
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0.020
71/’)7/0
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0.030
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0.030
71/0 /11
1?
10
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1.1 0
3.024
0.016
0.060
7 /09/16
17
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0.01 0 K
1.7rY)
0.030
0.027
0.090
K VALUE VNO N JO r E LESS
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