ENVIRONMENTAL PROTECTION AGENCY
OFFICE OK ENFORCEMENT
REPORT ON
WASTE DISCHARGE LIMITATIONS
FOR THE
ST.VRAIN CREEK BASIN
PREPARED FOR
REFUSE ACT PERMIT PROGRAM
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ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF ENFORCEMENT
Report on
WASTE DISCHARGE LIMITATIONS
FOR THE
ST. VRAIN CREEK BASIN
Prepared for
Refuse Act Permit P-ro.gram
Division of Field Investigations - Denver Center
Denver, Colorado
and
Region VTII
Denver, Colorado
January 1972
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TABLE OF CONTENTS
Section Title Page
I OBJECTIVES AND SCOPE 1
II BASIN DESCRIPTION 2
III WATER QUALITY STANDARDS 7
DESCRIPTION 7
I. Applicable Use Classifications 7
II. Applicable Criteria 8
Class A 9
Class B-l 10
Class B-2 11
Class C 11
Class D-l. 12
INDUSTRIAL AND MUNICIPAL COMPLIANCE SCHEDULES . . 13
POSSIBLE UPGRADING 13
IV WASTE SOURCES 15
Municipal Waste Sources 15
1. Lyons, Colorados Sanitation District Plant . . 15
2. Longmont Wastewater Treatment Plant. ..... 15
3. Boulder East Pearl Street Plant 17
4. Boulder 75th Street Wastewater Treatment Plant 18
5. Lafayette Wastewater Treatment Plant 18
6. Louisville Sanitation District Plant 18
7. Erie Sanitation District Plant 19
Industrial Waste Sources Investigated 19
1. Great Western Sugar Mill at Longmont, Colorado 19
Industrial Waste Sources Not Investigated .... 21
1. Gravel P:L Dewatering Operations 21
2. Allied Chemical Corporation, Jamestown Mine. . 22
3. Beech Aircraft Corporation, Boulder, Colorado. 2j
4. Public Service Company of Colorado, Valmont. . 24
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TABLE OF CONTENTS (Continued)
Section Title Page
V WATER QUALITY 27
Water Quality Survey - September 7-10, 1971 ... 28
Water Quality Survey - December 6-10, 1971. ... 35
VI EFFLUENT CRITERIA 38
A. APPLICABLE REFERENCE GUIDES 38
1. Beet Sugar Industry 38
2. Water Treatment Plants 38
B. RECEIVING WATER REQUIREMENTS 39
VII PERMIT RECOMMENDATIONS 41
1. Water Treatment Plants 41
2. Dewey Rocky Mountain Cement Company 41
3. Great Western Sugar Company, Longmont .... 42
4. Allied Chemical Corporation, Jamestown Mine . 45
5. Beech Aircraft Corporation, Boulder 45
6. Public Service Company of Colorado, Valmont . 46
VIII ADDITIONAL NEEDS AND PROBLEMS 48
1. TDS Levels from Proposed Nuclear Power Plant. 48
2. Discharges "Unreachable" Under the Present Law 48
3. Irrigation Reservoir Flushing 49
4. Seepage 49
5. Pretreatment 50
6. Industrial Expansion .* 50
REFERENCES 52
ii
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LIST OF TABLES
Table No. Title Page
1 St. Vrain Creek Basin Water Quality Investigations
Sampling Station Identification h
2 Seven-Day Low Flow - St. Vrain Creek - 1971 6
3 Municipal Waste Sources in the St. Vrain Basin 16
A Summary of Field Measurements & Chemical and Bacterial
Analyses - Great Western Sugar Mill, Longmont,
Colorado, December 5-8, 1971 20
5 Summary of Field Measurements and Analytical Results -
St. Vrain River Survey, September 7-10, 1971 29
6 Results of Bacterial Analyses at Selected Stations -
St. Vrain Creek Drainage Basin, September 7-10,
1971 32
7 Summary of Field Measurements and Analytical Results -
St. Vrain River Survey, December 6-10, 1971 36
8 Results of Bacterial Analyses - St. Vrain Creek
Drainage Basin, December 6-10, 1971 37
iii
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LIST OF FIGURES
Figure no. Title Page
1 Waste Sources & Stream Survey Stations for
St. Vrain Creek Drainage Basin 3
iv
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1
I. OBJECTIVES AND SCOPE
This report has been prepared by EPA, Region VIII and the Division
of Field Investigations, Denver Center, to determine necessary effluent
limitations for waste discharges in the St. Vrain Creek Basin. Such
limitations were developed to assure compliance with approved Water Quality
Standards and to meet requirements of the Federal Refuse Act Permit Program.
The South Platte River Basin Project, FWPCA, conducted studies^ ^
on the St. Vrain Creek drainage basin in January 1964 and in September,
October, and November 1965. These studies included municipal and indus-
trial waste source evaluations and stream surveys to determine the pollution
loads discharged and the effects on receiving waters. The information
gained from these studies was presented to the second session of the
Enforcement Conference in the Matter of Pollution in the South Platte River
Basin in the State of Colorado. At a reconvened session of that conference
held on November 6, 1966, the Conferees recommended that "All discharges
into the South Platte River Basin shall have adequate remedial or control
facilities in full operation by June 30, 1971, so as to comply with water
quality standards established by the Colorado Water Pollution Control
Commission as approved by the Secretary of the Interior."
This report discusses and updates the results of these evaluations
and makes recommendations on allowable effluent loads from major sources
in the basin. Status of compliance with previous requirements is also
evaluated.
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2
II. BASIN DESCRIPTION
St. Vrain Creek rises at the foothills of northwestern Boulder
County, flows easterly through the City of Longmont and then across
the plains and joins the South Platte River at RM 270. Boulder Creek,
a major tributary of St. Vrain Creek, flows through the City of Boulder
and enters St. Vrain Creek about 17.4 miles upstream from the mouth.
(Principle tributaries and features of the Basin are shown in Figure 1.
Numbers and letters shown on Figure 1 are identified in Table 1.)
Low flow conditions in the St. Vrain Creek Basin were examined
for the period of record from 1961 to 1970 (Table 2). The seven-day
average low flow recorded during sugar beet seasons within the ten-
year period was 3.1 cubic feet per second at Lyons during 1961. The
seven-day low flow during sugar beet seasons at the mouth was 87.8 cfs,
also in 1961. The seven-day low flow recorded at the mouth during the
ten-year period was 62 cfs in 1965. Many small irrigation diversions
deplete flow during the growing season, but do not materially affect
low flow conditions during the sugar beet processing season.
Agriculture and related industries are a major economic factor
within the Basin. The major industry affecting water quality is the
Great Western Sugar Company beet refinery at Longmont. Seven sources
discharge municipal wastes to Basin streams. These include Boulder
(population 67,000), and Longmont (population 24,000). The University
of Colorado is located at Boulder.
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I;i <»!*:<• 1. & I Waslr Source* <& Stream Survc\ Stations for Si Vraiii (!rcck Drainage lia^in
03
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DRAFT REPORT j
FOR INTERNAL USE ONLY .
I
TABLE ]
ST, VRAIN CREEK BASIN
WATER QUALITY INVESTIGATIONS
SAMPLING STATION IDENTIFICATION
Map No. River Mileage
A Great Western Sugar Company at 270.0/22.0
Longmont
B Longmont wastewater treatment 270.0/22.5
facility
C Lyons wastewater treatment facility 270.0/34.3
D Boulder 75th Street wastewater 270.0/17.4/18.0
treatment facility
E Boulder Pearl Street wastewater 270.0/17.4/21.3
treatment facility
F Erie wastewater treatment facility 270.0/17.4/7.9/2.5
G Lafayette wastewater treatment 270.0/17.4/7.9/8.6
facility
H Louisville wastewater treatment 270.0/17.4/7.9/13.7
facility
1 South Platte River upstream of 270.1
the mouth of St. Vrain Creek
2 South Platte River downstream of 264.7
St. Vrain Creek
3 St. Vrain Creek near mouth at USGS 270.0/1.3
gage
4 St. Vrain Creek at 1-25 270.0/14.6
5 Boulder Creek near mouth 270.0/17.4/1.9
6 Boulder Creek downstream of Coal 270.0/17.4/7.3
Creek (bridge on Highway-52)
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DRAFT REPORT
FOR INTERNAL USE ONLY
TABLE 1 (Continued
ST. VRAlN CREEK BASIN
WATER QUALITY INVESTIGATIONS
SAMPLING STATION IDENTIFICATION
Map No. River Mileage
7 Coal Creek near mouth (bridge on 270.0/17.4/7.9/1.0
Boulder County 58)
8 Boulder Creek upstream South Platte 270.0/17.4/14.2
supply canal (bridge on Boulder
County 19)
9 Boulder Creek downstream of South 270.0/17.4/20.2
Boulder Creek
10 Boulder Creek downstream of Boulder 270.0/17.4/19.9
(bridge on 55th Street)
11 Boulder Creek upstream of Boulder 270.0/17.4/27.6
at State Highway-119
12 St. Vrain Creek downstream of Great 270.0/20.6
Western Sugar discharge & 1/4 mile
downstream of the County Line Road
13 St. Vrain Creek downstream of 270.0/21.8
Longmont (bridge on County Line
Road)
14 St. Vrain Creek upstream of the 270.0/22.5
diversion point for Great Western
Sugar water supply & upstream of the
Longmont wastewater treatment plant
15 St. Vrain Creek upstream of Longmont
(bridge on County Road 25) 270.0/26.6
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DRAFT REPORT
FOR INTERNAL USE ONLY
j
TABLE 2
SEVEN-DAY LOW FLOW - ST. VRAIN CREEK —
1971
1/
Static;
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
St. Vran Creek at Lyons -
75 ft. southwest of State
Highwr-s 7666 (RM
Dates: 1/27-2/2 1/3-9
Avg. Flow CFS: 3.2 13.7
St. ViaJLn Creek near
Longno-'t - 630 ft. down-
stream of County Line
Road Bridge (RM 270.0/21.7)
(recorJo from 1965-68 only)
Dates:
Avg. Flow CFS:
St. Vrain Creek at Mouth,
r.ear Platteville, Colo.
(RM 270.0/1.3)
Avg.
Datesi
Flow CFS:
10/7-13
88
1/10-16
127
Boulder Creek near Orodell,
Colorado - (3 miles south-
vest of Courthouse in Boulder
on leCi b?nk along State
Highvj/ 119) (RM 270.0/17.4/
Dates: 11/18-24 7/10-16
Avg. Flow CFS: 3.7 17.1
2/26-3/3 3/6-12
5.7 0.3
4/29-5/5 5/4-10
28 40
1/3-9
5.4
11/4-10
3.3
3/24-30
1.8
4/16-22
16.5
1/8-14
62
3/24-30
4.8
4/5-11
17.2
5/2-8
45
10/24-30 1/14-20
3.6 14.0
1/1-7
3.8
4/3-9
14.0
4/6-12
41
1/17-23
3.6
2/8-14
7.8
4/6-12
20.4
3/11-17
72
4/8-14
9.1
4/5-11
5.8 '
2/4-10
4.5
4/29-5/5 3/10-16
41 125
10/25-31 10/1-7
5.8 11.0
If The 7-day low flows were calculated for only the 10-year period 1961-70.
a*
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7
III. WATER QUALITY STANDARDS
DESCRIPTION
On August 1, 1971, the Colorado State Water Pollution Control
Commission published notice of water quality standards for Colorado and
changes in stream classification. The procedural requirements of notice
and hearings were complied with to the satisfaction of the commission and
the following standards were adopted August 1, 1971, with an effective date
of September 1, 1971. These State Standards are considered to therefore
apply to St. Vrain Creek.
I. Applicable Use Classifications
St. Vrain Creek is contained within the South Platte River Basin
stream's tabulation in the Colorado State Standards. Seven sLretches
of St. Vrain Creek or its tributaries are tabulated and assigned
classifications. The table below indicates the Colorado State area
identification number, the stretch of the stream classified, and the
corresponding quality classification:
Area
No.
Area
From
To
Quality
Class
13 Coal Creek
16 S. Boulder Creek
17
19
James Creek
(Main Stem)
Bould-er Creek
20 North & South
St. Vrain Creeks
21 Main Stem of St.
Vrain Creek
22 Middle S'_. Vrain
Creek
Source.
State Hwy. //93
Sources
State Hwy. //119
Sources
Point of con-
fluence of N. &
S. St. Vrain Creeks
at Lyons, Colorado
Source Mouth
State Hwy. if93
Mouth
Mouth
Mouth
Point of con-
fluence at Lyons,
Colorado
Confluence with
S. Platte River
A,B^,C,D^
®2 >^'^1
AjB-pC ,D^
A,B2 ,C,DX
A,Bj,C,D-l
A,C ,D-^
A,B,
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8
Class A water, as defined by the Colorado State Standards, applies
to water withdrawn for treatment as a potable supply. Class water
is intended for the use of cold water fishery, Class B2 for warm
water fishery, and Class C water is intended for industrial uses
while Class water is intended for irrigation purposes.
II. Applicable Criteria
Six general paragraphs contained within the water quality stan-
dards for Colorado impose narrative criteria on the waters of St.
Vrain Creek. These six paragraphs are:
1. All wastes capable of treatment or control prior to discharge
into any waters of the State, shall receive secondary treatment
with disinfection or its industrial waste equivalent, as deter-
mined by the State Water Pollution Control Commission. Lesser
degrees of treatment or control may be permitted only where it
can be demonstrated that the standards applicable to the classi-
fied use of the water can be attained. Greater degrees of treat-
ment or control will be required where it can be demonstrated
that it is necessary to comply with the standards applicable to
the classified use of the water.
2. Free from substances attributable to municipal, domestic, or
industrial wastes, or other controllable sources that will either
settle to form unsightly, putrescent, or odorous bottom deposits,
or will interfere with the classified use of the water.
3. Free from unsightly floating debris, oil, grease, scum, and
other floating material attributable to municipal, domestic, or
industrial wastes, or other controllable sources.
4. Free from materials attributable to municipal, domestic, or
industrial wastes, or other controllable sources that will produce
objectionable odor, color, taste, or turbidity in the water, or
objectionable aquatic life which may result in eutrophication or
other conditions that interfere with the classified use of the
water.
5. Free from high temperatures, biocides, toxic, or other deleterious
substances attributable to municipal, domestic, or industrial
wastes, or other controllable sources in levels, concentrations,
or combinations sufficient to be harmful to human or animal life.
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9
6. Radioactive materials attributable to municipal, industrial
or other controllable sources will be minimum concentrations that
are physically and economically feasible to achieve. In no case
shall such materials in the stream exceed the limits established
in the current edition of the U. S. Public Health Service Drink-
ing Water Standards or the limits approved by the Federal Radiation
Council, or, in the absence of any limits specified by the U. S.
Public Health Service or the Federal Radiation Council, 1/30 of
the 168-hour-week values for other radioactive substances
specified in the National Bureau of Standards Handbook 69.
In addition, Colorado's nondegradation statement^ as it applies
to intrastate waters, limits the quality of the receiving water with
the following language:
Waters of the State, the quality of which exceeds the limits set
in these standards, will be maintained at existing quality unless
and until it can be demonstrated to the state that a change in
quality is justified to provide necessary economic or social
development. In that case, the best practicable degree of waste
treatment to protect the current classification of such waters
will be required.
The specific numerical criteria for the water quality classifi-
cations imposed on St. Vrain Creek (A, B]_, C, and D^) are as
follows:
CLASS A - The following standards shall apply to water withdrawn
for treatment as a potable supply:
a. Bacteria: Wastes or substances from controllable sources shall
not be discharged into these waters in amounts which will cause
the number of organisms of the fecal coliform group, as deter-
mined by either multiple tube fermentation or membrane filter
techniques, to exceed a log mean of 1000 per 100 milliliters
or exceed 2000 per 100 milliliters in more than 10 percent of
the samples collected in any 30-day period.
b. Dissolved Oxygen: Dissolved oxygen shall not be less than 4
milligrams per liter.
c. £H: The pH shall be maintained between 6.0 and 9.0.
d. Taste and Odor: Free from materials attributable to municipal,
domestic, or industrial wastes, or other controllable sources
thaL will produce taste or odor in the water.
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10
e. Dissolved Solids: Total dissolved solids, annual volume weighted
average, should be less than 500 milligrams per liter.
f. Selected Chemical Constituents: The following substances shall
not be present in such amounts as to exceed the specified concen-
trations in a potable water supply according to the mandatory
requirements of the latest edition of the U. S. Public Health
Service Drinking Water Standards:
Substance Concentration - mg/1
Arsenic ----------- 0.05
Barium- ----------- 1.00
Cadmium ----------- 0.01
Chromium (Hexavalent) - - - - 0.05
Cyanide ----------- 0.20
Lead ------------ 0.05
Selenium- ---------- 0.01
Silver- ----------- 0.05
CLASS B-l - The following standards shall apply to waters classified
for fish and wildlife (Cold Water Fishery)
a. Bacteria: Wastes or substances from controllable sources shall
not be discharged into these waters in amounts which will cause
the number of organisms of the fecal coliform group, as deter-
mined by either multiple tube fermentation or membrane filter
techniques, to exceed a log mean of 1000 per 100 milliliters
or exceed 2000 per 100 milliliters in more than 10 percent of
the samples collected in any 30-day period.
b. Dissolved Oxygen: In cold water fisheries, the dissolved
oxygen content shall in no case go below 6 milligrams per liter.
c. j)H: The pH shall be maintained between 6.5 and 8.5. No control-
lable pH change will be permitted which will interfere with fish
and aquatic life.
d. Turbidity: No turbidity shall exist in concentrations that will
impair natural and developed fisheries.
e. Jemperature: In cold water fisheries the temperatures shall not
exceed 70°F. No controllable temperature change will be permitted
which will interfere with the spawning and other aspects of fish
life.
f. Toxic Material: Free from biocides, toxic, or other deleterious
substances attributable to municipal, domestic, or industrial
wastes, or other controllable sources in levels, concentrations,
or combinations sufficient to be harmful to aquatic life.
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11
g. Other Material: Free from materials attributable to municipal,
domestic, or industrial wastes, or other controllable sources
that will produce off-flavor in the flesh of fish.
CLASS B-2 - The following standards shall apply to waters classified
for fish and wildlife (Warm Water Fishery):
a. Bacteria: Wastes or substances from controllable sources shall
not be discharged into these waters in amounts which will cause
the number of organisms of the fecal coliform group, as deter-
mined by either multiple tube fermentation or membrane filter
techniques, to exceed a log mean of 1000 per 100 milliliters
or exceed 2000 per 100 milliliters in more than 10 percent of
the samples collected in any 30-day period.
b. Dissolved Oxygen: In warm water fisheries, dissolved oxygen
content shall in no case go below 5 milligrams per liter.
c. pH: The pH shall be maintained between 6.5 and 8.5. No
controllable pH change will be permitted which will interfere
with fish and aquatic life.
d. Turbidity: No turbidity shall exist in concentrations that will
impair natural and developed fisheries.
e. Temperature: In warm water fisheries the temperatures shall
not exceed 90°F. No controllable temperature change wi]l be
permitted which will interfere with spawning and other aspects
of fish life.
f. Toxic Material: Free from biocides, toxic, or other deleterious
substances attributable to municipal, domestic, or industrial
wastes, or other controllable sources in levels, concentrations,
or combinations sufficient to be harmful to aquatic life.
g. Other Materia]: Free from materials attributable to municipal,
domestic, or industrial wastes, or other controllable sources
that will produce off-flavor in the flesh of fish.
CLASS C - The following standards shall apply to waters classified
for industrial uses:
a. Dissolved Oxygen: Dissolved oxygen content shall not go below
3 milligrams per liter.
b. jdH: The pH shall be maintained between 5.0 and 9.0.
c. Turbidj Ly: No turbidity shall exist in concentrations that will
interfere with established levels of treatment.
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12
d. Temperature: The temperature shall not exceed 90°F.
CLASS D-l - The following standards shall apply to waters classified
for irrigation:
a. Total Dissolved Solids (Salt) Concentration: A time-weighted
monthly mean at a monitoring station which exceeds the time-
weighted monthly mean for a base period established by the
Commission by more than two standard deviations shall be subject
to review by the Commission.
b. Sodium Adsorption Ratio: A time-weighted monthly mean at a moni-
toring station which exceeds the time-weighted monthly mean for
a base period established by the Commission by more than two
standard deviations shall be subject to review by the Commission.
c. Toxic Material: Free from biocides, toxic, or other deleterious
substances attributable to municipal, domestic, industrial wastes,
or other controllable sources in concentrations or combinations
which are harmful to crop life.
For purposes of quick reference, the table below indicates the prin-
ciple parameters of interest with respect to receiving water quality
standards, for the classifications:
Area
No.
Class
Fecal Coliform
Bacteria
D.O.
PPM
PH
T.D.S.
Temp
°F
13,17,
20
A,B^,C,D^
< 1000/100 ml*
6
6.5-8.5
<
500 mg/l*
70*
19
A,B2,C,D^
< 1000/100 ml*
5
6.5-8.5
<
500 mg/l*
90*
16
< 1000/100 ml*
5
6.5-8.5
—
90*
21
A,C,Di
< 1000/100 ml*
A
6.0-9.0
<
500 mg/l*
90*
22
A,B1
< 1000/100 ml*
6
6.5-8.5
<
500 mg/l*
70*
* Refer to standards for specific language.
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13
INDUSTRIAL AND MUNICIPAL COMPLIANCE SCHEDULES
Compliance schedules which were incorporated into the water
quality standards for the St. Vrain Basin are as follows:
City or Industry—^
Great Western Sugar
Company - Longmont
Golden Gravel Company -
Longmont
Beech Aircraft Corp.
Allied Chemical Corp. ,
Jamestown Mine
Dewey-Rocky Mtn.
Cement Company
C&M Sand & Gravel Co.
Flatiron Premix
Concrete Company
Ideal Industries Inc.
Public Service Company,
Valmont Plant
Type of Control
Closed flume water
recycling system
Closed cycle system
Chemical Treatment
Adequate treatment
required
Unknown
Unknown
Unknown
Unknown
Unknown
Date of Compliance
January 1968
None
None
None
None
None
None
None
None (in compliance)
POSSIBLE UPGRADING
As mentioned previously, a recent reclassification was adopted
with an effective date of September 1, 1971. In the St. Vrain Basin,
the reclassification specifically involved the addition of an A and C
classification to area No. 19, Boulder Creek, and an A classification
to area No. 21, the main stem from the north and south branch confluence
1/ All industries have applied for Corps of Engineers Refuse Act Permit.
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15
IV. WASTE SOURCES
Waste sources in the St. Vrain Creek Basin (Figure 1) were investi-
gated during the months of August, September, and December. Information
was obtained on water pollution control practices at each through in-plant
surveys and/or by contact with company representatives and with State and
local officials (Table 3).
Municipal Waste Sources
1. Lyons, Colorado, Sanitation District Plant - Treatment consists
of clarifier/digester, a one-acre aerated lagoon, and chlorination
facilities. The aerated lagoon and chlorination facilities were
added since the studies conducted by the South Platte River Basin
Project in 1966. At that time, Lyons was not providing adequate
secondary treatment.
Data were collected on this plant during September 27-29,
1971. Analyses of the effluent indicate that about 8 pounds per
day of BOD (20 mg/1 at 0.05 MGD) are discharged to St. Vrain
Creek. At the time of the survey, the St. Vrain Creek averaged
93 cfs (10-year - 7-day low flow at the gaging station is 0.8 cfs
which occurred during the month of March). At a loading of 8 lbs/day,
the BOD concentrations in St. Vrain Creek would increase about
2 mg/1 at 0.8 cfs.
2. Longmont Wastewater Treatment Plant - The Longmont system consists
of two plants with a total capacity of 5.24 MGD. The "old" plant
was constructed in 1960 with a design capacity of 4.0 MGD. A
study by the South Platte River Basin Project in 1966 indicated
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DRAFT REPORT j
FOR INTERNAL USE ONLY I
TABLE 3
MUNICIPAL WASTE SOURCES IN THE ST. VRAIN BASIN
Flow (MGD)
Name of
Facility
Type of
Treatment
Design Observed
(Ave.)
Removal Efficiencies
Receiving Date(s) of Observed (%)
Stream Evaluation
BOD
Susp. Solids Remarks
Boulder 75th Trickling filter
Street Plant with chlorination.
5.2
7.8
Boulder
Creek
8/17-20/71 60-90
64-> 83 Treatment inadequate
Plant under expan-
sion .
Boulder East
Pearl Street
Plant
Trickling filter
with chlorination.
4.2
4.3
Boulder
Creek
8/17-20/71 42-77
67-> 83
Treatment inadequate
Lyons
Clarigester
aerated lagoon
with chlorination.
Unknown 0.05
St. Vrain
Creek
9/28-29/71
Effluent grab
samples only.
Longr.ont
Trickling filter
and activated
biofilter with
chlorination.
5.2
5.5
St. Vrain
Creek
9/27-29/71 22-50
42-58
80+
Treatment inadequate
Erie Sanita-
tion District
1/
Lagoous
Unknown
Coal
Creek
Adequate according
to the State offi-
cials .
Louisville
1/
Oxidation ditch
with disinfection.
2500(PE) Unknown Coal
Creek
est 90
T~
Treatment adequate.
Plan addition of
lagoon for flex-
ibility of operatioi
Lafayette
1/
Trickling filter
with chlorination.
0.35
0.2
Coal
Creek
80
Treatment adequate,
1/ Facilities not visited by DFI-DC personnel.
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DRAFT REPORT j
FOR INTERNAL USE ONLY j
an operating efficiency of 72 percent. A biofilter plant was
subsequently constructed to raise plant capacity to its present
level.
An in-plant survey during September 27-29, 1971 showed that
about 57 percent of the flow is treated in the old plant. A
poultry processing plant (Turkey Processors) contributes 1.3 MGD
to the system. Chlorination is accomplished in the final clari-
fiers. It was noted during the survey that when the incoming
flow was in excess of 6 MGD, a portion of the primary effluent
from the old plant overflows to the outfall line. Artesian well
water is also discharged to this line serving as a "dilution is
the solution" means of waste treatment.
During the three-day survey, the overall efficiency of the
Longmont plants was in violation of State requirement for effec-
tive treatment, i.e., 80 percent minimum BOD removal.
The outfall line was sampled for a three-day period (December
5-8, 1971). The estimated flow was about 4 MGD and contained an
average BOD (three - 24-hour composites) concentration of 62 mg/1
or (2100 pounds BOD/day to St. Vrain Creek). The effluent makes
up the entire flow of St. Vrain Creek at the point of discharge
since the stream is essentially all diverted as a water supply
for the Great Western Sugar mill just upstream.
3. Boulder East Pearl Street Plant - Treatment is provided by a
high-rate trickling filter designed for 4.3 MGD. Studies by
the South Platte River Basin Project in 1967 indicated the treat-
iicit efficiency ucc less than 65 percent. During a survey conducted
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DRAFT REPORT
FOR INTERNAL USE ONLY .
_ . I 18
August 17-20, 1971, observed removal efficiencies varied from
42 to 77 percent. Flows at the plant averaged about 4 MGD and
adequate disinfection was being provided.
4. Boulder 75th Street Wastewater Treatment Plant - This facility
was constructed in 1968 at a design flow of 5.2 MGD. It presently
serves a population of approximately 40,000. During the survey,
August 17-20, 1971, the flows varied from 7.7 - 8.0 MGD. Accord-
ing to plant officials, the excess flow is due to infiltration.
The BOD removal efficiencies averaged 79 percent (range 66-90
percent). Adequate disinfection was being provided. Present plans
call for expansion of this facility to 15.6 MGD and, according to
plant officials, steps are being taken to help alleviate the in-
filtration problems.
5. Lafayette Wastewater Treatment Plant - Treatment is provided by
a standard rate trickling filter followed by disinfection. A
study by the South Platte River Basin Project in May 1966 reported
removal efficiencies of 58 percent. No survey was conducted, but
information obtained from an official of the Colorado State
Health Department indicate that this plant provides 80 percent
BOD removal consistently. All effluent is discharged to Coal
Creek.
6. Louisville Sanitation District Plant - Present treatment (design
population cf 2500) consists of an oxidation ditch followed by
disinfection. An official of the State Health Department reported
that BOD removals of 90 percent are achieved and that adequate
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DRAFT REPORT j
FOR INTERNAL USE ONLY ¦
I 19
disinfection is provided. Aerated lagoons are to be added after
the oxidation ditch to improve treatment flexibility. The effluent
is discharged to Coal Creek. No survey has been conducted.
7. Erie Sanitation District Plant - Treatment is provided by two
lagoons operated in series. The treatment efficiency is unknown.
The effluent goes to Coal Creek. No survey has been conducted.
Industrial Waste Sources Investigated
1. Great Western Sugar Mill at Longmont, Colorado - The Longmont mill
is a Steffen house operation processing about 3300 tons of beets
and 185 tons of molasses per day. Wastewater discharges from the
plant consist of condenser waters (001") and seepage from the ]ime
basins and surge ponds. During the period December 5-8, 1971, the
above waste discharges were sampled (Table 4).
The water supply for this plant is obtained from St. Vrain
Creek which is diverted in its entirety just upstream of the
Longmont sewage treatment plant outfall. Water in excess of plant
needs is discharged back to the St. Vrain in the same channel which
receives the condenser wastewater. Grab samples of the water
supply (SV-2) were collected over a 5-day period. The results of
the survey (Table 4) indicate that this mill discharges slightly
less than 1 pound of BOD per ton of beets processed. Discharge
conditions reported by the company for outfall 001 for the months
of October and November were as follows:
* Numbers in parentheses are the Refuse Act designations.
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DRAFT REPORT
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TABLE 4
SUMMARY OF FIELD MEASUREMENTS AND CHEMICAL AND BACTERIAL ANALYSES
GREAT WESTERN SUGAR MILL, LONGMONT, COLORADO
December 5-8, 1971
Field Measurements and Analytical Results
Flow
(MGD)
pH
Temp.
°C
Cond.
(lamhos/cm)
BOD
(mg/1)
TOC
(mg/1)
Alkalinity (mg/1)
Sta. //
Description ,Ave.
Range
Range
Range
Range
Ave.
Range
Ave.
Range
Average
SV-2
St. Vrain at 36
diversion point
for Great Western
Sugar Mill
7.7-8.4
5-13
1200-1380
2-15
10
5-91
69
230-265
260
GW-LONG-1
Condenser waterW 7.3
discharge (001) —
8.1-9.2
30-46
950-1300
30-54
46
25-84
61
205-225
213
GW-L0NG-2
Seep drain from 0.65
lime and surge
pond area
7.5-8.4
0-6
1400-2200
5-8
7
213-222
218
197-661
494
Bacterial Results
Total Coliform
Fecal Coliform
Fecal
Streptococci
Sta. il
Maximum
Log Mean
Minimum Maximum
Log Mean Minimum Maximum
Log Mean
Minimum
SV-2
2 ,100
1,200
570
2 70
190
84
2,3 00
930
560
GW-LONG-1
-
-
-
250
38
10
39,000
9,700
1,200
GW-LONG-2
-
-
-
440
< 34
<
10
53,000
7,500
2,300
1/ Numbers in parentheses are the Refuse Act Permit designations of the Great Western Sugar Company.
(S3
o
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DRAFT REPORT j
OE INTERNAL USE ONLY .
Parameter
October
November
BOD, mg/1
23
52
COD, mg/1
56
55
Total Solids, mg/1
901
994
Dissolved Solids, mg/1
770
846
Suspended Solids, mg/1
131
148
Total Volatile Solids, mg/1
168
148
Temperature, °C
maximum
48
43
minimum
AO
36
mean
43
38
PH
maximum
8.6
8.6
minimum
7.5
8.3
mean
8.1
8.5
Flow Rate, gpm
maximum
-
5082
minimum
-
4603
mean
-
4865
Alkalinity, mg/1 CaC03
217
184
Hardness, mg/1 CaCO^
406
448
Total Coliform MPN/100 ml
8.6*
1305
Fecal Coliform MPN/100 ml
290
145
Fecal Streptococci MPN/100 ml
2640
1035
Industrial Waste Sources Not Investigated
Several industries, having relatively minor or innocuous discharges,
were not investigated during the recent surveys. Investigation of dis-
charges from mines had not been completed at the time of this writing.
Information taken from permit applications is summarized below.
1. Gravel Pit Dewatering Operations - There are three facilities on
the St. Vrain Basin which are involved in dewaLering of gravel
or sand pits prior^to excavation. These are:
(1) Dewey Rocky Mountain Cement Company
(2) Flatiron Preroix Concretp Company
(3) Golden Gravel Company
The discharge quality in all three cases is comparable to
the receiving water quality and, therefore, no significant degra
aation occurs.. No survey has been conducted.
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22
2. Allied Chemical Corporation, Jamestown Mine - There is presently
one discharge from the Burlington shaft of the Jamestown mine.
The mine produces fluorspar (calcium fluoride) ore. The dis-
charge water is first collected at the operations levels, and
after settlement at the various levels in the mine, it is pumped
to a surface pond which has an estimated 72-hour retention time.
The water then drains to Little James Creek and subsequently to
James Creek which is used for the Jamestown water supply. Lime
treatment facilities are scheduled to be placed in operation by
March 1, 1972.
At the time of this writing, no data on the mine discharge
exists that is considered accurate. Data presented on the appli-
cation supposedly shows values after treatment with lime in a
jar test. The company stands by the figures, but they are so
extremely high that it is felt that the samples were shaken
prior to analysis. Data taken by the Boulder County Health De-
partment shows values at least an order of magnitude less for
such parameters as iron, manganese, and TDS. The Environmental
Protection Agency is presently conducting additional analyses on
the mine's discharges, but they will not be available until after
January 6, 1972.
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DRAFT REPORT i
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3. Beech Aircraft Corporation, Boulder, Colorado - Beech Aircraft,
Boulder Division, is primarily engaged in the manufacturing of
aircraft parts and auxiliary equipment. Their operations involve
some metal processing. Their effluent (2 discharges) has in the
past gone to ponds. The overflow from each pond was occasional,
and the overflow only left their property during periods of high
runoff. Any overflow during dry periods
was absorbed in the dry creek beds. Septic tanks are used for
sanitary -waste disposal.
Discharge 001 originally contained large amounts of chromium.
Treatment facilities for the chromium have now been added. Recent
measurements have not been able to detect any chromium in either
the influent or effluent of the pond. In an effort to further
improve the quality of the overflow, an air and water injection
system was added. This diluted the waste and caused a constant
overflow from the ponds. This dilution water and aeration has
minimized the turbidity and bad odor problem; however, the BOD
is still quite high. The BOD apparently results from the deter-
gent which presently is discharged to the pond in a 1000 gallon
batch discharge monthly. It is felt that very little biological
treatment is provided at the present time, probably because of
the monthly shock loading from the detergent discharge.
Discharge 002 is presently not flowing. There have been no
particular problems with this discharge. They are at a low point
in production and probably will not have a discharge until and
unless production increases.
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DRAFT REPORT j
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24
Discharges reported for outfalls 001 and 002 are as
follows:
001
002
Flow
100 gph
presently nil;
request 400 gpd
BOD
TDS
TSS
Nitrate
Phosphorous
Chromium
Surfactants
450 mg/1
38 mg/1
729 mg/1
0 mg/1
16
445 mg/1
15 mg/1
.005
9.0 yg/1
<•05 pg/1
250 mg/1
0 mg/1
Overflow from the ponds would not leave the property; except
during periods of runoff, the waste effluents could be carried by
the normally dry creek beds into Left Hand Valley Reservoir. The
overflow from the Reservoir is to both an irrigation ditch and to
Dry Creek, an unclassified stream. Flow from both Dry Creek and
the irrigation ditch is to Boulder Reservoir, the water supply for
Boulder. Boulder Reservoir discharge to Dry Creek which flows
into St. Vrain Creek below Longmont. At the point Dry Creek flows
into St. Vrain Creek, the classification of St. Vrain Creek is
A,C,D-^. The effluent definitely can effect and be a part of drink-
ing water and should be subject to drinking water standards.
4. Public Service Company of Colorado, Valmont - The Valmont plant
is about a 150 MW combination coal and natural gas fueled electric
generation station owned by Public Service Company of Colorado.
They have built a circulating reservoir (lake) system Lo serve aa a
source of cooling water and a source of dilution for their other wastes.
A discharge canal from the plant carries the cooling water, boiler
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DRAFT REPORT ;
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blowdown, water softener backwash, and rinse; floor drains, boiler
room sumps, storm sewers, and auxiliary equipment drains. In
addition, overflow from the ash settling pond also enters the lakes.
The discharge filed for is the overflow from the lakes. Be-
cause of the extreme dilution involved there seems to be no
immediate problems. The exact contents of the coal, or more im-
portant the heavy metals that might be in the ash pond overflow
are not known. Public Service has checked for mercury and claims
there is no problem. Other metals have not been analyzed for
although Public Service claims there is no problem since "Western"
coal is used in their furnaces.
During much of the year they take in and discharge no water.
Their flow figures on their latest application reflect the average
and maximum discharge when they are discharging. As previously
mentioned, they do discharge their boiler water softening backwash
effluent, along with their drains, directly into the lake. Elimi-
nation of this practice would be expensive because of the plumbing
involved.
The lakes are game preserves and serve as duck and geese
havens. This was verified by Environmental Protection Agency
personnel. The ponds also support some fish life. Company
officials claim there are bass, perch, and carp in the lake.
Reported present discharge conditions are as follows:
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DRAFT REPORT
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26
Flow
BOD
TDS
TSS
0-23.8 mgd (10 mgd average discharge)
<5 mg/1
178-295 mg/1
15-50 mg/1
Temperature
Zinc
Oil
PH
79°F (maximum)
20-60 Mg/1
negligible
7.6-8.6
Based on the limited data in the application, there appears
to be no increase, other than that attributable to evaporation,
in phosphorus and chromium.
South Boulder Creek at the discharge point is classified as
B2, C, and D^. Pertinent parameters under this classification
are a pH between 6.5 and 8.5 and a maximum temperature of 90°F.
Temperature change is not to be such that it "will interfere with
spawning and other aspects of fish life."
Since fish are thriving in the ponds, levels of toxicants are
not apparently being exceeded and the maximum stream temperature
requirement of 90° is not a problem. The impact of temperature
change on the fish life in the receiving water is unknown at this
time. However, during the late summer when the maximum pond temp-
eratures occur, flow in South Boulder Creek can be as low as 0.5 cfs
because of irrigation diversion and fish population is therefore
almost non-existent at this time.
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. i 27
V. WATER QUALITY
Water quality studies were conducted in the St. Vrain Basin during
[ 3]
the periods September 27-28 and October 1, 2, and 4, 1965, from the
headwaters downstream to the mouth, including Boulder Creek. The survey
showed the headwaters streams to be of good quality with the BOD about 2.0
mg/1 and the dissolved oxygen levels near saturation. The Creek downstream
from Lyons generally approximated the headwaters conditions except for the lar^e
increases in coliform bacteria. UDStream of Longmont, the waterway had
low BOD and coliform concentrations and a high dissolved oxygen level.
Municipal and industrial discharges from Longmont caused a
considerable change in water quality with the BOD levels rising to 10 mg/1
and fecal coliform concentrations increasing to 140,000 MPN/100 ml. The
lower portion of St. Vrain Creek was influenced by the inflows from Boulder
Creek. St. Vrain Creek quality downstream from the Boulder Creek confluence
was as follows: 7-10 mg/l BOD, dissolved oxygen at 85-96 percent of saturation
and fecal coliform concentrations varying from 6,000 to 18,000/100 ml.
Boulder Creek upstream from the City of Boulder showed good water quality in
1965. Downstream of the Boulder wastewater treatment plant discharge,
BOD concentrations increased to 50 mg/1 and the dissolved oxygen levels
dropped to 70 percent saturation. The bacterial densities were relatively
low because of heavy chlorination of the Boulder plant effluent. Boulder
Creek downstream of Boulder showed recovery froir the waste discharges.
Further loads were added to Boulder Creek via Coal Creek which receives
the waste loads from the communities of Erie, Lafayette, and Louisville.
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DRAFT REPORT j
FOR ETERNAL USE ONLY j
. 2
In the lower reaches of Boulder Creek, the DO range was 5-11 mg/1 with
the dissolved oxygen from 83-117 percent of saturatio
Water Quality Survey - September 7-10, 1971
The St- Vrain Creek survey extended from just upstream of Longmont
(RM 26.6) downstream to the mouth and included the Boulder Creek drainage
from near Boulder (RM 27.6) downstream to its mouth.
Upstream from Longmont, St. Vrain Creek waters were of good quality
(Tables 5 and 6 ). A variety of invertebrates were found to inhabit
the stream bed. Among these were forms sensitive to organic pollution
including mayflies, caddisflies, and stonefl'ies. Game fish, including
trout and bass were common in St. Vrain upstream from Longmont. Downstream
from Longmont, sewage, feedlots, and irrigation activities debased the
quality of St. Vrain Creek. Approximately 2100 lbs of BOD per day were
discharged by the Longmont wastewater treatment plant. Fecal coliform
densities increased to 1400/100 ml. At RM 14.6 organic solids settled
to the Creek bed forming sludge deposits. The bottom animal community
was reduced to forms considered tolerant of organic pollution.
Near the St. Vrain Creek mouth (RM 1.3), water quality improved
although the water was still murky, sludge deposits were less evident and
bacterial densities were reduced. The bottom dwelling community in this
region included a few pollution sensitive forms such as stoneflies, cad-
disflies, and mayflies. The water quality remained unsuitable for popula-
tions of game fish, and the fish community was dominated by carp, bdbt>,
and various minnows.
Boulder Creek, the main tributary of St. Vrain Creek, had good water
quality at the sfption upstream nf Boulder (RM 27.6). The BOD valuer were
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DRAFT REPORT !
FOR INTERNAL USE ONLY ;
TABLE 5
SUMMARY OF FIELD MEASUREMENTS AND ANALYTICAL RESULTS - ST. VRAIN RIVER SURVEY
SEPTEMBER 7—10, 1971
Map "Jo.
Sta_ion Descrl-ptior
Flow
CFS
pit
S.U.
Cond.
(uTjios/cm)
Temp.
°C
D.O.
hr/1
X
Saturation
Total
Alkalinity
BOD
mfi/1
Total
Solids
itik/1
Susp.
Solids
ms/1
T0C
mg/1
1
Soyt'i Platte River
u'js'.refm of St, Vrain
Croc'-..
(If! 270.1)
Ave rage
Range
6.2-7.8
900-1310
20
15-23
5.0
3.8-5.7
88
79-106
6.8
2.9-9.4
760
630-920
90
20-200
9
6-15
2
Scji-'t Platte River
dovn-atrean of St.
Vrj^.i Creek.
(KM '.64. 7)
Average
Range
7.0-8.0
1000-1400
20
15-22
6.8
5.7-7.3
129
98-143
7
3-11
970
880-1070
92
10-130
7
4-13
3
St. '/rain River
nerr mouth at
USGb gage.
(Hi-. 270.0/1.3).
Average
Range
211
6.5-8.2
1100-1500
20
17-24
7.2
4.3-8.7
91
60-110
21
20-24
3.5
2.3-5.6
1075
950-1230
42.5
10-110
6
6-7
4
St.. Vrain River at
1-25
(Ri 270.0/14.6)
Ave rage
Range
7.5-8.3
1100-1450
20
16-24
8.8
6.6-10.5
109
83-138
3.9
3.4-4.4
1020
910-1240
<
32.5
10-80
7
4-9
5
BouU'er Creek near
the "iouth.
(!C' 270. 0/17. 4/1.9)
Average
Range
6.7
7.9-8.6
1200-1400
21
14-26
12.1
9.4-14.6
146
108-180
27-30
2.8
1.4-4.3
975
900-1080
<
<
20
10-30
9
3-17
6
Boulder Creek down-
s'., of Coal Creek
(bruise on Hvy.52).
('<• 270 0/17.4/7.3)
Average
Ranj;e
6.5-8.9
490-650
21
14-25
10.6
8.4-13.7
121
93-160
152
6.1
5.0-8.0
377
300-450
<
<
27.5
10-50
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DRAFT REPORT
FOR EXTERNAL USE ONLY
TABLE 5 (Continued)
SUMMARY OF FIELD MEASUREMENTS AND ANALYTICAL RESULTS - ST. VRAIN RIVER SURVEY
SEPTEMBER 7 -10, 1971
Mao No.
Sc 'tioi Description
Flow
CFS
pH
S.U.
Cond.
(ymhos/cm)
Temp.
°C
D.0.
mfc/l
Z
Saturation
Total
Alkalinity
BOD
mfi/1
Total
Solids
nift/1
Susp.
Solids
mfi/1
TOC
ms/1
7
Cja1 Creek near mouth
(bridge on Boulder
Cou.-'ry 58).
(IU 270 0/17.A/7.9/1.0)
Average
Range
2.8
6.2-8.3
1100-1200
20
12-25
8.3
7.5-9.4
102
81-125
> 9
6.5-12.8
845
7 70-890
<
23
10-40
8
Bounder Creek up-
s:r?3 of South Platte
v-only canal (bridge
on ioulder County 69)
('-! 2 70.0/17.4/14. 2) Average
Range
7.5-8.0
400-470
20
14-22
7.6
6.4-8.6
95
7 3-110
-
267
250-280
<
<
20
10-50
9
Eoulcler Creek down-
strec-i of South Boulder
Cioek.
(R.". 270/17. 4/20. 2) Average
Range
6.7-7.8
260-400
20
14-23
6.7
4.7-8.3
85
65-106
94-100
> 3.0
> 6.6-8.8
185
140-230
<
<
15
10-30
8
4-11
10
Boulder Creek down-
si rcjri of Boulder
(bridge on 55ch Street)
(-,-l 270.0/17.4/19.9) Average
Range
6.8-7.4
200-480
19
14-21
7.1
6.4-8.2
88
79-102
77-78
> 11
> 6.9-14.0
185
110-260
<
<
12.5
10-20
11
Boulder Cr&ek up-
SLrc:n of Boulder
a'. itate Kuy.119.
(<¦ 270.0/17.4/27.6) Average
Ran Re
56
7.3-7.5
70-440
15
11-17
8.5
8.0-8.9
97
92-102
1.9-25.0
0.9
0.8-1.0
65
40-80
<
<
10
10
< 3
< 1-4
W
O
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draft report
fob. internal use only
TABLE 5 (Continued)
SUMMARY OF FIELD MEASUREMENTS AND ANALYTICAL RESULTS - ST. VRAIN RIVER SURVEY
SEPTEMBER 7--L0, 1971
Man No.
Station Description
Flow pH Cond. Temp. D.O.
CFS S.U. (umhos/cm) ^C mg/l
Saturation
Total
Alkalinity
BOD
ng/l
Total
Solids
rcg/1
Susp.
Solids TOC
mR/1 ma/1
12 St. Vrain dovnstream of
Lo^cn-oit (bridge on
Co'j.ity Lire Road).
(X>! 270.0/21 8)
Average
Range
13 St Vrain upstream of
Lon^-ncrtt (bridge on
County Road 25).
(XM 2 70.0/26.6)
Average
Range
7.6-3.1 520-1200
6.9-7.9 260-340
20
14-24
20
16-25
8.4
6.5-9.7
7.8
6.9-8.7
105
84-125
99 .
85-115
9
4.8-13
630
390-710
1.3 205
1.2-1.5 170-260
4.7
Oj
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: , DRAFT REPORT 1
FOR INTERNAL USE ONL\ j
TABLE 6 .. - -
RESULTS OF BACTERIAL ANALYSES AT SELECTED STATIONS
ST. VRAIN CREEK DRAINAGE BASIN
SEPTEMBER 7-10, 1971
Total Coliform Fecal Coliform Fecal Streptococcus
Map Count/100 ml Count/100 ml Count/100 ml
Key Station Description Maximum Log Mean Minimum Maximum Log Mean Minimum Maximum Log Mean Minimum
1
South Platte River upstream
of the mouth of St. Vrain
Creek.
(RM 270.1)
200,000
>130,000
73,000
32,000
11,000
2,700
18,000
14,000
11,000
2
South Platte River down-
stream of St. Vraift
Creek.
(RM 264.7)
>800,000
>100,000
5,000
> 6,000
> 1,800
230
10,000
4,700
2,400
3
St. Vrain Creek near
mouth at USGS gage.
(RM 270.0/1.3)
38,000
13,000
3,600
1,600
500
54
7,400
5,500
3,100
5
Uoulder Creek near mouth.
(RM 270.0/17.^/1.9)
2,600
2,200
1,800
2,300
790
360
40,000
4,400
810
6
Boulder Creek downstream
of Coal Creek (bridge on
Ilwy 52)
(RM 270.0/17.4/7.3)
15,000
2,300
480
820
150
37
6,500
4,500
3,300
7
Coal Creek near mouth
(bridge on Boulder
County 58).
(RM 270.0/17.A/7.9/1.0)
49,000
16,000
2,400
2,000
1,300
610
120,000
72,000
26,000
OJ
hO
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¥
draft report
?OR INTERNAL USE ONLY
TABLE 6 (Continued)
RESULTS OF BACTERIAL ANALYSES AT SELECTED STATIONS
ST. VRAIN CREEK DRAINAGE BASIN
SEPTEMBER 7-10, 1971
Map
Key
10
11
Station Description
3oulder Creek downstream
of Boulder (bridge on 55th
S treet).
(RM 270.0/17.A/19.9)
Boulder Creek upstream of
Boulder at State Hwy 119.
(RM 270.0/17.4/27.6)
12 St. Vrain Creok downstream
of Great Western Sugar dis-
charge and 1/4 mile down-
stream of County Line Road.
(RE 270.0/20.6)
Total Coliform
Count/100 ml
Fecal Coliform
Count/100 ml
Fecal Streptococcus
Count/100 ml
Maximum Log Mean Minimum Maximum Log Mean Minimum Maximum Log Mean Minimum
5,500 3,000 1,400
680
370
210
58
32
18
37,000 19,000 5,500 4,400 1,400
310
170
90
<19 <10
260
155
96
510 26,000 11,000 6,100
13 St. Vrain Creek downstream
of Longmont (bridge on
County Line Road).
(RM 270.0/21.3)
14,000 7,600 3,800
420
290
240 2,100
780 450
Co
OJ
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DRAFT REPORT ;
FOE INTERNAL USE ONLY .
low and the water was free from serious bacterial contamination. The
biota of this stream reach was quite diverse consisting of many organisms
intolerant of organic pollution. The fish population of this reach in-
cluded game fish such as rainbow trout. Downstream from the Boulder waste
water treatment plants, the bacterial quality remained acceptable indicat-
ing the plants were practicing adequate disinfection. However, the water
was turbid and smelled of sewage and the stream bed was blanketed with
sewage sludge and supported only organisms tolerant of organic pollution.
Farther downstream, Boulder Creek quality improved Benthic
organisms indicative of a recovery zone were collected, but pollutants
carried by Coal Creek (fecal coliform concentrations of 1300/100 ml, BOD
of 13 mg/1) degraded the quality of Boulder Creek at RM 7.3. At this
station the BOD equaled about 8 mg/1. Boulder Creek water quality was
sufficiently improved at RM 1.9 to support diverse bottom community and
a fish population of bass and non-game fish.
In summary, the severe effects of pollution reported during the
water quality studies of the South Platte River Basin Project in 1965 on
both Boulder Creek and St. Vrain Creek were less evident during the Sep-
tember 1971 survey. Water quality was degraded by sewage discharged to
Boulder but had successively improved downstream to Coal Creek. Sewage
contaminated Coal Creek chemically and bacteriologically, and degraded
Lower Boulder Creek. The quality of the St. Vrain Creek has improved
somewhat downstream of Longmont. In past years, the Kuner Empson Cannery
at Longmont contributed over 3000 lbs of BOD and over 1000 lbs of solids
per day to St. Vrain Creek subsequently degrading the receiving waters
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DRAFT REPORT j
OR INTERNAL USE ONLY , 35
for several miles downstream. This condition was not observed during
the 1971 survey. Downstream of Longmont, there was less bacterial con-
tamination than was observed in 1965, and the diversity of benthic or-
ganisms increased especially near the mouth of the Creek.
Water Quality Survey - December 6-10, 1971
A stream survey was conducted at selected stations on St. Vrain Creek
during the period December 6-10 to ascertain the effects of waste discharges
from the Great Western mill at Longmont, Colorado. Waste loads discharged
by the sugar mill and the Longmont wastewater treatment plant were also
measured.
Water quality conditions upstream of the Great Western mill and the
Longmont wastewater treatment plant (RM 22.5) showed 2-15 mg/1 BOD and low
bacterial densities (Tables 7 and 8 ). The dissolved oxygen concentra-
tions were above 10 mg/1 during the daylight sampling conducted. Down-
stream (RM 20.6) the effects of organic pollution from the mill and the
Longmont wastewater treatment plant (flow approximately 4 MGD) were evi-
dent. The BOD concentrations ranged from 8-40 mg/1 (average 24 mg/1) and
the DO levels (range 0.3-3.7 mg/1) showed violations of the Colorado
standards for waters classified suitable as an industrial supply (i.e.,
3.0 mg/1). Log mean fecal coliform concentrations had increased over
600 percent. Sludge banks were observed at the downstream station. At
the time of this survey, the Longmont wastewater treatment plant and the
Great Western mill weie contributing an average daily BOD load of 4900 lbs
to the St. Vrain Creek. A discussion of pollution abatement needs in the
St. Vrain Creek Basin is contained in the subsection entitled "Water
Quality Improvement Measures."
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TABLE 7
SUMMARY OF FIELD MEASUREMENTS AND ANALYTICAL RESULTS
ST. VRAIN RIVER SURVEY
DECEMBER 6-10, 1971
Flow pH Cond. Total
Map Avg, S.U. ynhos/cm Temp. °C P.O. ng/1 X Saturation Alkalinity mg/1 BOD rag/1 TOC mg/1
No. Satlort Description CFS Rarge Range Ran Re Avg. Ran Re Avg. Range Avg. Range Avg. Range Avg. Range Avg.
12 Sc. Vrain Creek 56.0 7.7-8.4 1200-1375 5-12 9 0.3-3.7 2.1 11-35 28 230-265 250 8-40 24 5-91 69
do-nstream of Great
'.'cstern Sugar Co.
di^cKarge and 1/4
"lilt; downstrean of
County Line Road.
270.0/20.6)
14 Sl. Vrain Creek up- 38.5 7.7-8.3 825-1350 0-1 < 1 10.4-12.6 11.3 87-105 94 198-230 215 2-15 11 3-75 53
i,ircara of the diversion
point for Great Vcstern
gar Co. water supply
nrd upstream of the
L'jngnont wastewater
'.leatment plant.
(k:; 270.0/22.5)
u>
ON
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TABLE 8
RESULTS OF BACTERIAL ANALYSES
ST. VRAIN CREEK DRAINAGE BASIN
DECEMBER 6-10, 19 71
Total Coliform Fecal Coliform Fecal Streptococcus
Map Count/100 ml Count/100 ml Count/100 ml
Key Station Description Maximum Log Mean Minimum Maximum Log Mean Minimum Maximum Log Mean Minimum
12 St. Vrain Creek downstream 740,000 > 40,000 940 96,000 > 1,300 10 81,000 12,000 810
of Great Western Sugar
J_scharge & 1/4 mile
downstream of the County
Line Road.
(RM 270.0/20.6/
14 Sc. Vraxn Creek upstream
of the diversion point
for Great Western Sugar
water supply & upstream
of the Longmon" waste-
v/at^r treatment plant.
(HM 270.0/22.5)
2,100 1,200 570
270 190 84
2,300 930 560
u>
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38
VI. EFFLUENT CRITERIA
A. APPLICABLE REFERENCE GUIDES
1. BEET SUGAR INDUSTRY
Suggested reference guides for this industry were developed by per-
sonnel of the Environmental Protection Agency Research and Monitoring
Division; data was obtained primarily from existing Environmental Pro-
tection Agency grants to the industry as well as from a "state of the art"
document prepared by the Beet Sugar Development Foundation under a grant
from the Environmental Protection Agency. The suggested values were
generally accepted at the Environmental Protection Agency Technical Re-
view Meeting in July 1971 and a meeting with industry representatives in
September 1971 resulted in an "informal agreement" in which the industry
spokesman staled that the numbers for pH, BOD, and suspended solids were
technically achievable by the 1973-74 campaign. The reference guides are
as follows:
The COD value is subject to change as additional data on COD/BOD
ratios are obtained. Receiving water requirements are of course under-
stood to prevail if they dictate more stringent values.
2. WATER TREATMENT PLANTS
No reference guides were developed for water treatment plants under
the original contract; it is felt that a suspended solids level of 30 mg/1
and a range of 6.5-S.5 is a good representation of sccoii^cry trect-.e.it
for these discharges.
Suspended solids
PH
Fecal coliforms
COD
B0D5
0.50 lbs/ton beets sliced
0.50 lbs/ton beets sliced
6.0 - 9.0
75 x 106 organisms/ton.beets sliced
0.90 lbs/ton beets sliced
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B. RECEIVING WATER REQUIREMENTS
An evaluation of the adequacy of the suggested effluent limitations
detailed in the reference guides is necessary to determine whether com-
pliance with water quality criteria will be achieved. If water quality
criteria are not met, greater reductions of waste must be required of each
waste source receiving a Refuse Act permit. The parameters of concern in
the St. Vrain Creek Basin are dissolved oxygen (DO) and coliform concen-
trations. Total dissolved solids may also be an important parameter.
Based on 1971 data, the major DO depression (utilizing the lowest values
observed) occurs downstream of Longmont, Colorado. Low flow observations
at this location were only available for a 4-year period of record. How-
ever, the flow in the St. Vrain downstream of Longmont during drought
periods or periods of heavy irrigation withdrawal consists only of the
combined waste discharge from the Longmont municipal treatment plant and
the Great Western plant plus about 1 cfs of natural drainage. This rep-
resents a total of 8 cfs. Waste loads from the municipal plant were
predicated on a minimum 85 percent removal being consistently achieved
and typical deoxygenation rates for municipal sewage. Wastes from Great
Western were based on 0.5 lbs of 5-day BOD per ton of beets processed per
day. The combined 5-day BOD loading to the Creek is 3320 lbs per day.
Upstream residual was negligible (less than 20 lbs per day). Calculations
were made at a stream temperature of 20°C due to the excessive temperature
recorded in the effluent (greater than 30°C). The reaeration coefficient
was derived from Churchill's formula and based on stream hydrological
characteristics. The minimum DO which would occur is about 0.8 mg/1, well
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DRAFT REPORT I
FOR INTERNAL USE ONLY j 40
below the approved criterion of 4.0 mg/l. This is a reasonable expectation
since the stream flov7 is almost entirely waste effluent. Greater waste reduc-
tions than required by the reference guides are necessary at the Great Western
plant. Liekwise, the municipal treatment plant has a higher effluent than
expected for domestic sewage receiving 85 percent removal, due the seasonal
operation of a turkey processing plant which discharges to the municipal system.
If the Great Western plant is required to discharge 0.5 lbs of 5-day BOD
per ton of beets processed per day, as is presently being accomplished for the
Great Western plant at Eaton, Colorado, and if the maximum effluent concen-
tration from the Longmont municipal plant is held to 25 mg/l (representing an
estimated overall 93 percent removal) and both waste discharges are required
to maintain a residual DO of 4.0 mg/l in the effluent, the minimum DO to be
expected under these conditions at a critical temperature of 10°C is 5.7 mg/l.
This leaves very little, if any, room for industrial expansion at Longmont if
the DO criterion is raised to 5.0 mg/l as may be proposed. Both waste dis-
charges under the conditions enumerated would be required to attain an overall
removal of 93 percent each. The Longmont municipal treatment plant can reach
this efficiency if pretreatment is required at the turkey processing plant.
With respect to coliform concentrations, water quality criteria can be
met with efficient disinfection at the municipal plant and attainment of
proposed permit requirements at the Great Western plant. Total dissolved
solids in blowdown water from the Public Service Company nuclear power plant
will be controlled through proposed permit requirements.
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41
VII. PERMIT RECOMMENDATIONS
Suggested permit conditions and rationale for the major discharges
in the St. Vrain Basin are as follows:
1. Water Treatment Plants
Special conditions for these discharges will essentially consist
of the following:
Flow As reported plus ]0%
Suspended Solids 30 mg/1
pH 6.5-8.5
The above criteria will force the plants to provide neutralization
where necessary, as well as sludge removal. The slight increase in
flow will minimize requests for new permits if minor expansions
occur in the future.
It is suggested that permits be issued for periods of 6-18
months depending on the status of individual construction plans,
with extension to five years if criteria are met.
2, Dewey Rocky Mountain Cement Company
Flatiron Premix Company
Golden Gravel Company
It is suggested that the special conditions reflect the present
reported discharge rates and water quality with approximately a ten
percent expansion in the limitations on these parameters. This will
allow a degree of flexibility which will minimize requests for new
permits if minor expansions in pumpage rates occur in the future.
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- . J 42
Although reported values for suspended solids are less than
30 mg/1, a limitation of 30 mg/1 will be imposed in the event that
future operations cause the discharge of unusual amounts of sus-
pended so]ids.
It is suggested that analyses be conducted monthly during
dewatering operations.
It is suggested that permits be issued for five years.
3. Great Western Sugar Company, Longmont
More than half the BOD and the great majority of the fecal
coliform contributions to the St. Vrain River in this area are made
by the Longmont municipal plant. This plant does not provide ade-
quate treatment on a continuous basis. The BOD concentrations in
the municipal plant effluent vary widely because of the load imposed
by the poultry processing plant. The municipal treatment should be con-
sistent with the discharge requirements for the Great Western mill.
Furthermore, until the mill intake and/or the municipal outfall
location changes, there will be a 0.3 mile stretch of the stream
receiving little more than municipal waste effluent during periods
of low flow.
It is suggested that the following limitations shall apply to
the Longmont mill as part of the specia] conditions of the permit.
1. BOD^ discharges shall not exceed 0.5 lbs per ton of beets
sliced or 1650 lbs per day, whichever is less, or COD
shall not exceed 0.9 lbs per ton of beets sliced or 3000
lbs per day, whichever is less.
2. Suspended solids discharges shall not exceed 0.5 lbs per
ton of beets sliced or 1650 lbs per day, whichever is
less.
3. Dissolved oxygen in effluent to be not lass thdn 4.0 mg/1.
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43
4. The number of fecal coliform organisms shall not exceed
10 x 10^ organisms per ton of beets sliced.
5. pH shall be between 6.0 and 9.0.
6. Any discharge of accumulated x^astewaters at a later date
shall not exceed 1650 lbs per day. Total discharges of
BOD and suspended solids during and after a campaign
shall not exceed 0.5 lbs multiplied by the total tons of
beets sliced during the campaign.
7. Discharge temperatures shall not exceed 32°C.
The above criteria for BOD and suspended solids represent the refer-
ence guides. The criteria for fecal coliforms represent a fraction
of the reference guide, since the mill discharge is apparently well
below the reference guide at present.
A COD criterion was introduced as an alternate to BOD because
there is some evidence that nitrification might be taking place in
the BOD test. Implementation of these values will result in a con-
tinuation of flume water recycle, a more diligent operation of the
condenser system, and will essentially eliminate any end-of-
campaign dumping unless the routine discharges are greatly improved.
The temperature limitation assures compliance with the maximum
temperature criteria of the water quality standards. It does not
allow a zone of mixing and will force the mill into some form of
cooling and/or recycle. No standards exist for incremental tempera-
ture rise, since the stream is not classified for fisheries in this
reach.
More stringent requirements are not considered justified at this
time because computations show that if the municipal treatment plants
achieve the equivalent of secondai'y treatment, water quality stand-
ards wi]1 not be violated.
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•••• - .J 44
It is suggested that the fol]owing monitoring schedule be in-
cluded as a special condition of the permit. During the sugar beet
campaign, each discharge will be monitored for the parameters
listed below at the stated frequencies. Discharge following the
campaign shall be monitored according to the following schedule,
but no less than two samples should be obtained if the discharge
occurs for less than a two-week period.
Parameter
Frequency of
Collection
Frequency of
Measurement
Flow Rate
pH
Biochemical Oxygen Demand
(bod5)
Chemical Oxygen Demand
or Total Organic Carbon
Total Solids
Total Suspended Solids
Ammonia (as Nr)
Nitrate (as N)
Fecal Coliform
Temperature
Not Applicable
Hourly for 8 hours
8-hour Composite
8-hour Composite
8-hour Composite
S-tiour Composite
8-hour Composite
8-hour Composite
Grab Sample
Grab Sample
Bi-ueekly
Bi-weekly
Bi-weekly
Bi-weekly
Bi-weekly
Bi-weekly
Bi-weekly
Bi-weekly
Bi-weekly
Bi-weekly
Note: 8-hour composite should be considered as one sample collected
hourly for 8 consecutive hours and composited in proportion to the
flow rate. Samples must be properly preserved.
It is recommended that a permit be issued for existing conditions
for a period of six months, with extension to two years if the
above criteria ere mcl-.
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... . _ .. . J 45
A, Allied Chemical Corporation, Jamestown Mine
If conditions are as reported in the application, a permit
should be denied. It is felt, however, that the Environmental
Protection Agency analyses will show significantly lower levels
of pollutants. Recommendations for permit conditions cannot be
made, therefore, until the data are reported after January 6.
5. Beech Aircraft Corporation, Boulder
It is suggested that the following maximum values be applied
to the company's discharges.
001
002
BOD
30 mg/1
30 mg/1
Total Chromium
0.1 Mg/1
0.05 Mg/1
TDS
500 mg/1
750 mg/1
TSS
20 mg/1
20 mg/1
Flow
100 gph
700 gpd
In addition to the above, the statement that "no discharge of ma-
terials or combinations of materials that may be hazardous or toxic"
should be included.
It is recommended that they be required to meet the BOD parameter
in about nine months but that the other parameters be effective im-
mediately. The BOD limitation of 30 mg/1 is considered the equiva-
lent of secondary treatment. Although it should be attainable with
installation of an equalization basin and extended aeration with a
polishing pond, the option of completely dewatering their discharge
will probably be more appea]ing to the company.
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_ _ j ^
If a discharge continues, it is recommended that their discharge
be monitored for the above parameters monthly with an annual submittal
of data.
6. Public Service Company of Colorado, Valmont
Since this pJant presents a situation in which discharge is in-
termittent, and since there exist unknown contributions of organic
matter and nutrients from the wildlife in the ponds, the recommended
limitation will be given in qualitative units only.
Specific effluent maximum limitations are suggested as follows:
TSS 30 mg/1
Oil and Grease 5 mg/1
pH 6.0-8.5
Temperature 80°
Flow 10 mgd (avg.) 25 mgd (maximum)
Mercury 0.1 lbs/day
It is considered unjustified to assign specific concentrations
at this time for phosphates, chromium, iron, copper, zinc, cadmium,
and mercury. This is essentially because of lack of data; no in-
formation exists for some of the above and data show a decrease in
concentrations in others. In addition, since fish and wildlife ap-
parently thrive in the ponds there is no sense of urgency involved.
;
It is recommended that additional data on these parameters be
gathered and that it be made clear that limitations may be imposed
on them at a later date.
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47
The first four suggested parameter limitations reflect present
discharges and will effectively prevent the company from signifi-
cantly changing its operational pattern.
The mercury level reflects Environmental Protection Agency
policy; the company feels that mercury presents no problem to them.
It is suggested that the following analytical schedule be
followed. Grab samples will be sufficient. Samples are to be
taken during discharge periods only. If results show insignificant
levels, the schedule may be modified.
Parameter
Frequency
Flow
Bi-weekly
Temperature
Bi-week]y
TSS
Monthly
pH
Monthly
TDS
Monthly
Total Chromium
Monthly
Phosphates
Monthly
Zinc
Monthly
Iron
Annually
Copper
Annually
Mercury
Annually
BOD
Annually
Cadmium
Annually
It is suggested that a permit be issued for a two-year period.
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FOE EXTERNAL USE ONi.Y ; 4
VIII. ADDITIONAL MEEDS AND PROBLEMS
1. TDS LEVELS FROM PROPOSED NUCLEAR POWER PLANT
A problem in the southwestern United States is the continuous build-
up of TDS in the rivers and streams. Virtually every power plant in this
part of the country uses cooling towers or ponds not because of thermal
pollution control but because the shortage of water demands it. As the
water is cooled, significant amounts are lost to the atmosphere and the
concentration of TDS is proportionally increased.
The specific problem is the proposed discharge from a nearly com-
pleted nuclear plant with a cooling water discharge that will occasionally
increase the TDS of the South Platte River by more than 5 percent. A
clear violation of the anti-degradation clause of the water quality stand-
ards will occur but the plant presently exists and is ready to go on line.
As mentioned elsewhere, no reference guides for TDS have been developed
and the only alternative is the much more expensive closed cooling water
system for plants presently in the design stage.
2. DISCHARGES "UNREACHABLE" UNDER THE PRESENT LAW
The best example of this is the Great Western Sugar mill at Greeley,
Colorado. It has been suggested that a permit be issued which will re-
quire them to meet the reference guides for the industry. There is some
question about whether this is adequate for the receiving water conditions.
However, significant pollutants are entering the same reach of stream from
a municipal plant providing inadequate treatment and from feedlots in the
area; these latter two sources are of course largely exempt from the Refuse
Act under the present rules and regulations. Should unusually strigent
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DRAFT REPORT j
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controls be placed on one industry while others, contributing the majority
of pollution in the area, are not pursued?
3. IRRIGATION RESERVOIR FLUSHING
A typical example of this problem is Seaman Reservoir which is a
man-made water collection reservoir on the North Fork of the Cache la
Poudre River. It was built for and is owned and operated by the City of
Greeley, Colorado. The River above the reservoir periodically carries
considerable silt. The reservoir acts as a natural settling basin for
these solids. The solids can only accumulate to a certain point before
they must be flushed. Therefore, periodically the reservoir must be
drained and the silt that has been collected, flushed down the stream.
This concentrated dose of suspended solids visually affects the quality
of the stream and it is suspected that there is considerable harm to the
aquatic life as well.
The solids are going to settle in this reservoir no matter what is
done. Dredging is impossible. Discharge during high flow, more frequent
flushing to minimize any one dump, or a combination seem to be the most
obvious solutions presently.
Do discharges of this type come under the Refuse Act?
4. SEEPAGE
It is currently not known how serious a problem this is; it is obvious,
however, that as more industries close their systems, it will come to the
forepoint.
A classic example occurs at a sugar mill which has "closed" its system
by retaining its water in a pond. However, a groundwater interception ditch
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DISAFT REPORT j
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.. ! 51
exists near the pond which picks up flow (probably a great amount from
the pond) by accretion and subsequently discharges to a stream. No
application was filed for this discharge since it carries only "ground-
water accretion."
5. PRETREATMENT
As mentioned earlier, the Longmont wastewater treatment plant receives
wastes from a poultry processing plant which cause the incoming waste loads
and, consequently, the waste loads to the receiving stream to vary widely.
Discharge requirements for this plant will need to be consistent with
those recommended for the Great Western mill which will be required to
reduce present waste loads to reflect base level treatment, i.e., 0.5 lbs
BOD/ton of beets sliced. The present waste flows from this mill, this
would mean an effluent concentration not exceeding 30 mg/1. In order to
meet this effluent concentration in the Longmont treatment plant effluent,
an overall removal of about 93 percent plus adequate disinfection would
need to be achieved. Pretreatment of the Turkey Processors wastes to
reduce the BOD concentration to levels consistent with raw domestic sewage
(i.e., 200 mg/1) should aid in achieving the above removal efficiencies.
6. INDUSTRIAL EXPANSION
The waste loads to be discharged to the St. Vrain Creek Basin, if
criteria specified herein are met, should maintain water quality at
acceptable levels. Calculations indicate that during extreme low flow
conditions the discharges from the Longmont sewage treatment plants and
from the Great Western Sugar plant at Longmont, will cause depression of
instream dissolved oxygen to the minimum permitted by applicable water
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DRAFT REPORT j
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quality standards for Lower St. Vrain Creek. It is thus clear that no
further industrial expansion involving discharge of oxygen demanding
materials can be permitted in the Basin until a higher degree of treat-
ment than than specified can be provided for the discharges at Longmont.
An exception to this limitation might be permitted in the upper reaches
of basin streams if it can be shown that complete recovery could be
attained upstream of Longmont.
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REFERENCES
52
1. U. S. Department of the Interior, Federal Water Pollution
Control Administration, South Platte River Basin Project,
Water Quality, Middle Basin Tributary Streams, South Platte
River Basin, Summer 1965. PR-7. Denver, Colorado, Decem-
ber 1967.
2. U. S. Department of Health, Education, and Welfare, Federal
Water Pollution Control Administration, South Platte River
Basin Project, Report to the Second Session of the Conference
in the Matter of Pollution of the South Platte River Basin.
April 27, 1966.
3. U. S. Department of the Interior, Federal Water Pollution
Control Administration, Proceedings, Conference in the Matter
of Pollution of the South Platte River Basin in the State of
Colorado, Second Session, Denver, Colorado, Reconvened Novem-
ber 10, 1966.
4. State of Colorado, Department of Health, Water Pollution
Control Commission, Water Quality Standards for Colorado.
1970.
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