U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
11ASHKENODE LAKE
ST, UDUIS COUNTY
MINNESOTA
EPA REGION V
WORKING PAPER No, 111
PACIFIC NORTHWEST ENVIRONMENTAL RESEARCH LABORATORY
An Associate Laboratory of the
NATIONAL ENVIRONMENTAL RESEARCH CENTER - CORVALLIS, OREGON
and
NATIONAL ENVIRONMENTAL RESEARCH CENTER - LAS VEGAS, NEVADA
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REPORT
ON
HASHKhNODE LAKE
ST, IMS COUNTY
MINNESOTA
EPA REGION V
WORKING PAPER No, 111
WlTH 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 1
II. Lake and Drainage Basin Characteristics 3
III. Lake Water Quality Summary 4
IV. Nutrient Loadings 9
V. Literature Reviewed 14
VI. Appendices 15
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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 [ g106 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.
ACKNOWL EDGMENT
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 Koochi chi ng
Bear Freeborn
Bemidji Beltrami
Big Stearns
Big Stone Big Stone, MN; Roberts,
Grant, SD
Birch Cass
Blackduck Beltrami
Blackhoof Crow Wing
Budd Martin
Buffalo Wright
Calhoun Hennepin
Carlos Douglas
Carrigan 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
Walimark Chisago
White Bear Washington
Winona Douglas
Wolf Beltrami, Hubbard
Woodcock Kandiyohi
Zumbro Olmstead, Wabasha
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nnesota
Map Location
MASHKENODE LAKE
® Tributary Sampling Site
X Lake Sampling Site
Sewage Treatment Facility
— — Direct Drainage Area Limits
1/2 !ML
-L
(
S
Tr.atvn.n Focility near Evekth 2.5 Mi
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MASHKENODE LAKE
STORET NO. 2756
I. CONCLUSIONS
A. Trophic Condition:
Survey data indicate that Mashkenode Lake is eutrophic. Of
the 60 Minnesota lakes surveyed in the fall of 1972, when essen-
tially all were well—mixed, 30 had less mean total phosphorus,
15 had less mean dissolved phosphorus, and 11 had less mean in-
organic nitrogen. Of the 80 Minnesota lakes sampled, 43 had
greater Secchi disc transparency, and 49 had less mean chloro-
phyll a.
Survey limnologists noted that water quality was generally
poor on all visits. High turbidity, anaerobic conditions with
hydrogen sulfide evident, and intensive algal blooms and large
areas of floating macrophytes were observed.
B. Rate-Limiting Nutrient:
The results of the algal assay show that nitrogen was the
limiting nutrient at the time the sample was collected. The lake
data also indicate that nitrogen was limiting at the other
sampling periods (N/P ratios were less than 8/1 on all occasions).
C. Nutrient Controllability:
1. Point sources--During the sampling year, Mashkenode Lake
received a total phosphorus load at a rate more than six times
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2
that proposed by Vollenweider (in press) as hdangerousu; i.e.,
a eutrophic rate (see page 13). Of that load, it is estimated
the Nichols Township wastewater treatment plant contributed
nearly 88%.
It is calculated that complete removal of phosphorus at the
point source would reduce the loading rate to 5.8 lbs/acre/yr
or 0.65 g/m 2 fyr (a mesotrophic rate). If 100% removal can be
accomplished, the trophic condition of Mashkenode Lake should
improve.
2. Non—point sources (see page 13)——The phosphorus export
of the unnamed stream (B-i) compares well with the mean phosphorus
export of five unimpacted tributaries of nearby Swan Lake* (28 lbs/
mi 2 /yr).
In all, it is estimated that non-point sources contributed
about 12% of the total phosphorus load to the lake during the
sampling year.
* Working Paper No. 129.
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II. LAKE AND DRAINAGE BASIN CHARACTERISTICS
A. Lake Morphometry :
1. Surface area: 101 acres.
2. Mean depth: 7 feet.
3. Maximum depth: 14 feet.
4. Volume: 707 acre/feet.
5. Mean hydraulic retention time: 40 days.
B. Tributary and Outlet:
(See Appendix A for flow data)
1. Tributaries -
Name
Unnamed stream (B-l)
Minor tributaries &
immediate drainage -
Totals
2. Outlet -
Two Rivers
C. Precipitation***:
1. Year of sampling: 29.8 inches.
2. Mean annual: 26.9 inches.
Drainage area* Mean flow*
16.7 mi2 8.6 cfs
0.7 mi
.2
17.4 mi
.2
0.4 cfs
9.0 cfs
17.6 mi2** 9.0 cfs**
t DNR lake survey map (1964).
* 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 mi^.
** Includes area of lake; outflow adjusted to equal sum of inflow.
*** See Working Paper No. 1, "Survey Methods".
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4
III. LAKE WATER QUALITY SUMMARY
Mashkenode 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 or more depths at one station on the lake (see map, page vi).
During each visit, a single depth—integrated (near bottom to surface)
sample was collected for phytoplankton identification and enumeration;
and during the last visit, a single five-gallon depth-integrated sam-
ple was collected for algal assays. Also, each time a depth-integrated
sample was collected for chlorophyll a analysis. The maximum depth sam-
pled was 12 feet.
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
tines, refer to Appendix B.
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5
A. Physical and chemical characteristics:
FALL VALUES
(10/19/72)
Parameter Minimum Mean Median Maximum
Temperature (Cent.) 3.8 3.8 3.8 3.8
Dissolved oxygen (mg/l) 12.0 12.0 12.0 12.0
Conductivity (pmhos) 300 300 300 300
pH (units) 8.7 8.7 8.7 8.7
Alkalinity (mg/l) 87 89 88 92
Total P (mg/i) 0.050 0.053 0.052 0.058
Dissolved P (mg/i) 0.016 0.018 0.019 0.019
NO + NO (mg/l) 0.040 0.040 0.040 0.040
Arn onia mg/1) 0.070 0.077 0.080 0.080
ALL VALUES
Secchi disc (inches) 36 41 42 46
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6
B. Biological characteristics:
1. Phytoplankton -
Sampling Dominant Number
Date Genera per ml
07/10/72 1 . Cyclotella 904
2. Oocystis 832
3. Asterionella 687
4. Fragilaria 452
5. Flagellates 307
Other genera 1 ,321
Total 4,503
09/09/72 1 . Microcystis 6,396
2. Aphanocapsa 5,766
3. Peridinium 2,432
4. Dictyosphaerium 1,261
5. Ana aena 811
Other genera 4,054
Total 19,459
10/19/72 1. Cyclotella 15,639
2. Flagellates 2,632
3. Fragilaria 2,030
4. Cylindrocystis 1,654
5. Anabaena 827
Other genera 4,286
Total 27,068
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7
Maximum yield
( mg/i-dry wt. )
2.6
2.7
2.4
2.4
2.4
32.2
9.2
24 . 3
13.7
2. Chlorophyll a -
(Because of instrumentation problems during the 1972 sampling,
the following values may be in error by plus or minus 20 percent.)
Sampling Station Chlorophyll a
Date Number ( pg/i )
07/10/72 01
09/09/72 01
10/19/72 01 37.9
C. Limiting Nutrient Study:
1 . Autoclaved, filtered, and nutrient spiked -
Ortho P Inorganic N
___________ Conc. (mg/i) Conc. (mg/i ) _____________
0.017 0.100
0.022 0.100
0.027 0.100
0.037 0.100
0.067 0.100
0.067 10.100
0.017 10.100
Spike (mall ) ____________ ____________ ______________
Control
0.005 P
0.010 p
0.020 P
0.050 P
0.050 P + 10.0 N
10.0 N
2. Discussion -
The control yield of the assay alga, Selenastrum capri-
cornutum , indicates that Mashkenode Lake had a moderately
high rate of primary productivity at the time the assay sam-
ple was collected.
The lack of change in yield when phosphorus spikes were
increased and the significant increase in yield when only
nitrogen was added show nitrogen limitation.
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8
The lake data at each of the three sampling times indi-
cate nitrogen limitation; i.e., the N/P ratios were less than 8/1,
and nitrogen limitation would be expected.
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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
months of May and August 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 Minne-
sota 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 /year, in nearby Swan
Lake tributaries at stations B-l , C-i, G-1 , H-i, and J-l and multiplying
the means by the ZZ area in mi 2 .
Nichols Township did not participate in the Survey and nutrient loads
were estimated at 2.5 lbs P and 7.5 lbs N/capita/year.
* See Working Paper No. 1.
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10
A. Waste Sources:
1. Known municipa1 -
Pop. Mean Receiving
Name Served Treatment Flow (mgd) Water
Nichols 1 ,702* stab. pond 0.170** Creek to
Township Mashkenode Lake
2. Known industrial - None
t Anonymous, 1974.
* 1970 Census.
** Estimated at 100 gal/capita/day.
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11
B. Annual Total Phosphorus Loading - Average Year:
1. Inputs -
lbsP/ %of
Source yr total
a. Tributaries (non-point load) -
Unnamed Creek (B-i) 550 11.4
b. Minor tributaries & immediate
drainage (non-point load) - 20 0.4
c. Known municipal —
Nichols Township 4,260 87.8
d. Septic tanks - None
e. Known industrial - None -
f. Direct precipitation* - 20 0.4
Total 4,850 100.0
2. Outputs -
Lake outlet - Two Rivers 1 ,250
3. Net annual P accumulation - 3,600 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) -
Unnamed Creek (B-i) 20,950 60.5
b. Minor tributaries & immediate
drainage (non-point load) - 820 2.4
c. Known municipal
Nichols Township 12,760 36.9
d. Septic tanks - None
e. Known industrial - None - -
f. Direct precipitation* - 970 0.2
Total 35,500 100.0
2. Outputs -
Lake outlet - Two Rivers 15,580
3. Net annual N accumulation - 19,920 pounds
* See Working Paper No. 1.
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13
D. Mean Annual Non-point Nutrient Export by Subdrainage Area:
Tributary lbs P/m1 2 /yr lbs N/mi 2 Jyr
Unnamed Creek (B-i) 33 1 ,254
E. Yeariy Loading Rates:
In the following table, the existing phosphorus loading
rates are compared to those proposed by Volienweider (in press).
Essentially, his “dangerous” rate is the rate at which the
receiving waters would become eutrophic or remain eutrophic; his
pernissib1e 11 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
lbs/acr /yr 48.0 35.6 351.5 197.2
grams/rn /yr 5.38 4.00 39.4 22.1
Volle 2 weider loading rates for phosphorus
(g/m /yr) based on mean depth and mean
hydraulic retention time of Mashkenode Lake:
“Dangerous” (eutrophic rate) 0.84
“Permissible” (oligotrophic rate) 0.42
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14
V. LITERATURE REVIEWED
Anonymous, 1974. Wastewater disposal facilities inventory. MPCA,
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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TRIBUTARY FLOW INFORMATION FOR MINNESOTA 10/30/74
LAKE CODE 2756 MASHKENODE LAKE
TOTAL DRAINAGE AREA OF LAKE 17.60
SUB—DRAINAGE NORMALIZED FLOWS
TRIBUTARY AREA JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC MEAN
275661 17.60 0.61 0.65 2.12 45.40 22.20 11.60 9.20 2.95 3.42 6.11 4.02 1.07 9.11
275681 16.70 0.61 0.64 2.09 42.80 21.00 11.00 8.74 2.80 3.26 5.80 3.81 1.04 8.63
2756ZZ 0.90 0.02 0.01 0.07 1.93 1.02 0.61 0.42 0.11 0.18 0.21 0.14 0.04 0.40
SUMMARY
TOTAL DRAINAGE AREA OF LAKE z 17.60 TOTAL FLOW IN = 108.35
SUM OF SUB—flRAINAGE AREAS 17.60 TOTAL FLOW OUT = 109.35
MEAN MONTHLY FLOWS AND DAILY FLOWS
TRIBUTARY MONTH YEAR MEAN FLOW DAY FLOW DAY FLOW DAY FLOW
2756A1 10 72 3.81 15 3.80
11 72 2.01 12 2.60
12 72 0.70
1 73 0.49 9 0.50
2 73 0.66
3 73 4.54 9 0.90
4 73 9.99 18 8.90
5 73 16.90 2 11.00 19 8.10
6 73 8.24 7 4.60
7 73 4.05
A 73 5.66 19 12.60 25 4.50
9 73 2.01 23 1.40
275681 10 72 3.61 15 3.60
II 72 1.91 12 2.40
72 0.68
1 73 0.49 9 0.50
2 73 0.65
3 73 4.47 9 0.90
4 73 9.42 18 8.40
5 73 16.00 2 11.00 19 7.70
6 73 7.81 7 4 .4Q
7 73 3. S
8 73 5.38 19 8.60 25 4.30
9 73 1.92 23 1.30
27562 ? 10 7 0.15 IS 0.20
11 7? 0.07 12 0.09
1? 72 0.02
I 73 0.02 9 0.02
2 73
3 73 0.1S 9 0.03
4 73 0.42 1 0.40
S 73 0.7A 2 0.50 19 0.40
6 73 0.43 7 0.20
7 73 0.10
0 73 0.21 19 0.47 25 0.17
9 73 0.11 23 0.07
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APPENDIX B
PHYSICAL and CHEMICAL DATA
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STORET RETRIEVAL DATE 74/10/30
275601
47 49 42.0 092 35 52.0
MASHKENOOE LAKE
27 MINNESOTA
11EPALES 2111202
3 0015 FEET DEPTH
00010 00300 00077 00094 00400 00410 00630 00610 00665 00666
DATE TIME QE TH WATER DO TRANSP CND&JCTVY PH T * 1K N02&N03 NH3—N PHOS—TOT Pt$OS—DIS
FROM OF TEMP SECCHI FIELD CACO3 N—TOTAL TOTAL
TO DAY FEET CENT G/L INCHES MICROMHO SU MG/L MG/I MG/I MG/L P MG/I P
7?/07/1O 18 30 0000 46 270 9.30 102 0.110 0.080 0.074 0.023
18 30 0004 ‘2.0 11.2 300 9.20 99 0.090 0.070 0.076 0.022
- 18 30 0012 17.9 0.2 330 7.40 119 0.370 0.630 0.277 0.131
77/09/09 08 18 0000 15.6 42 305 8.80 108 0.070 0.080 0.092 0.028
08 18 0005 15.6 9.3 300 8.83 109 0.060 0.800 0.124 0.026
72/10/19 15 10 0000 36 300 8.70 87 0.040 1.075 0. OSI 0.0 16
15 10 0004 3.8 12.0 300 8.70 92 0.040 0.580 0.058 0.019
15 10 001 3.8 12.0 300 8.70 88 0.040 0.080 0.052 0.019
3721 7
DATE TIME DEPTH CHLPPHYL
FROM OF A
TO DAY FEET IJG/L
77/07/10 18 30 0000 ?4.3J
77/09/09 0$ 18 0000 13.7J
77/10/19 15 10 0000 37.9J
J VALUE KNOWN TO E IN ERROR
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APPENDIX C
TRIBUTARY DATA
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ST)°ET RETRIEVAL DA1T 74/10/30
?756A1 LS27 56A1
47 29 30.0 092 36 00.0
UNNAMED Ti IH FROM LK TO TWO RIVE
27 7.5 EVELETrI
O/M sHKENODF LAKE
XING 3.5 M NW OF EVELETH
IIEPALES 2111204
4 0000 FEET DEPTH
0 63C 33675 00610 00671 00665
DATE TIME 1) T’- NO2f NO3 TOT i JEL hJH3—r’! iOS—DIS PHOS—TOT
FROM OF N—TOTAL N TOTAL UPTHO
TO DAY FEET M(,/L MG/L MG/L MG/L P MG/L p
72/10/15 16 45 0.026 0.89? 0.081 0.007 0.070
72/11/17 10 15 0.042 0.840 ).087 0.0?? 0.075
71/04/1 lB “) 0.014 0.901’ 0.021 0.006 0.075
73/05/0? 18 3 ) 0.012 0.780 0.011 0.007 0.075
73/05/19 II 45 J. OI OK 0.560 0.009 0.010 0.070
73/06/07 14 45 0.011 0.96’) 0.060 0.050 0.057
73/0 4/19 14 35 .027 1.050 0.090 0.110
71/OM/?S L7 70 0.k60 0.036 0.029 0.050
71/09/23 11 45 0.500 I.G50 0.075 0.008 0.120
K VALUE. KNOWN TO E LESS
THAN I ’JDICATED
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STO ET PETI lEV4L DATE 7 e/1(J/3O
2756131 LS2756 1
47 30 30.0 092 34 30.0
UNNAMED TRIB TO LK FROM N SLOE
27 CO #69. SHEET #3
1/MASKENODE LAKE
CO HWY 103 XING ABOV NICHOLS SIP
1 1EPALES 2111204
4 0000 FEET DEPTH
0063u 006?5 00610 00671 00665
DATE TIME DE°TH NO &NO3 TOT KJEL N-13—N PHOS—DIS PHOS—TOT
FROM OF N—TOTAL N IOTAL ORTriO
TO DAY FEET MG/L ‘AG/L Mr,fL MG/L P MG/L P
7?/10/IS 16 30 0.870 0.350 0.07? 0.005K O.0?0
7?/11/12 10 45 0.46( O.7 ) 0.130 0.005K
73/O4/J 19 10 O.?31 0. ’ R0 0.038 0.006 0.050
73/05/0? IR 15 fl.7 - ,? C.6Q0 0.026 0.00 5K 0.040
71/05/1 14 00 O.3 4O 0.480 0.035 0.008 0.015
73/06/07 14 35 0.800 0.6 ’.0 0.069 0.022 0.050
7 3 /O9/I 14 ‘+0 L.50i) 0. 70 0.034 0.011 0.025
73/OR/?c 17 10 1.2?0 0.175 0.04? 0.006 0.020
71/09/ 3 1? iS i.lh O O. 40 C.088 0.075
K VALUE KNO SN TO BE LESS
THAN INDICATED
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STORET RETRIEVAL DATE 74/10/30
275651 TF275651 P012450
47 31 30.0 092 34 30.0
VIRGINIA
27 7.5 VIRGINIA
T/MASNKENODE
UNNAMED STREAM
IIEPALES 214)204
4 0000 FEET DEPTH
00630 00625 00610 00671 00665 50051 50053
DATE TIME DEPTH NO2 .NO3 TOT cJEL NH3-N PIIOS—DIS PHOS—TOT FLOW CONDUIT
FROM OF N—TOTAL N TOTAL ORTHO RATE FLOW—M&0
TO DAY FEET HG/L MG/L MG/I HG/I P HG/L P INST M60 MONTHLY
73/01/31 11 00
CP(T)— 10.000 14.000 0.140 4.175 4.700 2.060 2.160
73/01/31 13 00
73/02/2R ii 00
CP(T)— M.7 00 8.R00 0.155 3.600 4.400 2.350 2.040
73/02/2M 13 00
73/03/11 11 00
CP(T)— 9.400 6.900 0.540 3.500 4.200 2.700 2.480
73/03/31 13 00
73/04/30 11 00
CP(T)— 9.700 9.200 0.041 3.100 4.000 3.000 2.350
73/04/30 13 00
73/05/29 11 00
CP(T)— 10.000 7.200 0.350 3.500 4.500 2.540 2.740
73/05/29 13 00
71/06/30 11 00
CP(T)— R.200 2.?00 0.650 2.200 3.300 2.560 2.370
73/06/30 13 00
73/07/31 11 00
CP(T)— 9.200 2.400 1.030 3.100 3.500 2.680 2.590
73/07/31 13 00
73/OR/3 1 10 00
CP(T)— 5.700 2.960 3.600 2.100 2.480
73/OR/31 1? 00
73/09/30 11 00
CP(T)— 7.800 .?O0 0.360 3.900 4.300 2.120 2.280
73/oq/30 13 00
73/10/31 I I 00
CP(T)— 9.700 6.500 0.090 3.330 4.400 2.120 2.670
73/10/31 13 00
73/11/30 II 00
CP(T)— M.400 6.150 0.190 4.400 6.250 2.370 2.300
73/11/30 13 00
74/01/01 11 00
CP(T)— 13.000 6.100 0.051 4.050 5.100 2.300 2.300
74/01/01 13 00
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STOPET ETPIEVAL P)ATF 74/10/30
275651 TF275651 P012450
47 31 30.0 092 34 30.0
VIRGINIA
27 7.5 VIRGINIA
T/ ’1ASHKEr ’JODE
UNNAMED STI €.AM
11E’ ALES 141204
4 0000 FEET DEPTH
c ’30 O0’? (V)610 00671 00665 50051 50053
r)ATE [ PIE DF’ T -l NO 7 NO3 TOT PcJFL JH3—N Phos—DIS I-iOS—TOT FLOW CONDUIT
FOOM (W rJ—tOTAL N TOTAL OPTkO RATE FLOW—MGO
TO DAY FFET (‘/L MG/I MG/L MG/L P MG/L P INST MGD MONTHLY
74/01/31 11 00
CP(T)— 10.1G 4.cO O 0. lPfl 4.600 7.600 2.240 2.740
74/01/31 13 00
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