APPENDIX B
WATER QUALITY ASSESSMENT
CD
UD
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CONTENTS
Page
LIST OF FIGURES iii
LIST OF TABLES iv
INTRODUCTION B-l
B-I. SUSPENDED SOLIDS DEPOSITION B-2
SMALL DISCHARGER APPROACH B-2
LARGE DISCHARGER APPROACH B-6
B-II. DISSOLVED OXYGEN CONCENTRATION FOLLOWING INITIAL DILUTION B-15
B-III. FARFIELD DISSOLVED OXYGEN DEPRESSION B-23
SIMPLIFIED MATHEMATICAL MODELS B-25
NUMERICAL MODELS B-35
EVALUATION OF FIELD DATA B-36
B-IV. SEDIMENT OXYGEN DEMAND B-38
B-V. SUSPENDED SOLIDS CONCENTRATION FOLLOWING INITIAL DILUTION B-44
B-VI. EFFLUENT pH AFTER INITIAL DILUTION B-48
B-VII. LIGHT TRANSMITTANCE B-53
B-VIII. OTHER WATER QUALITY VARIABLES B-61
TOTAL DISSOLVED GASES B-61
CHLORINE RESIDUAL B-61
NUTRIENTS B-62
COLIFORM BACTERIA B-64
REFERENCES B-68
B-ii
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FIGURES
Number Page
B-l Projected relationships between suspended solids mass
emission, plume height-of-rise, sediment accumulation,
and dissolved oxygen depression for open coastal areas B-3
B-2 Projected relationships between suspended solids mass
emission, plume height-of-rise, sediment accumulation,
and dissolved oxygen depression for semi-enclosed
embayments and estuaries B-5
B-3 Example of predicted steady-state sediment accumulation
around a marine outfall B-10
B-4 Dissolved oxygen deficit vs. travel time for a submerged
wastefield B-28
B-5 Farfield dilution as a function of 12€0t/B2 B-33
B-iii
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TABLES
Number Page
B-l Example tabulations of settleable organic component by
group and maximum settling distance by group B-12
B-2 Example tabulations of deposition rates and accumulation
rates by contour B-13
B-3 Typical IDOD values B-17
B-4 Dissolved oxygen saturation values B-21
B-5 Subsequent dilutions for various initial field widths and
travel times B-41
B-6 Selected background suspended solids concentrations B-46
B-7 Calculated values for the critical effluent Secchi depth (cm)
for selected ambient Secchi depths, initial dilutions, and a
water quality standard for minimum Secchi disc visibility of
1 m B-58
B-iv
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INTRODUCTION
This appendix provides detailed guidance for responding to water
quality-related questions in the Application Questionnaire. Methods for
predicting values of the following water quality variables are presented:
• Suspended solids deposition
• Dissolved oxygen concentration following initial dilution
• Farfield dissolved oxygen depression
• Sediment oxygen demand
• Suspended solids concentration following initial dilution
• Effluent pH after initial dilution
• Light transmittance
• Other water quality variables.
B-l
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B-I. SUSPENDED SOLIDS DEPOSITION
The applicant must predict the seabed accumulation due to the discharge
of suspended solids into the receiving water. Two prediction methods are
described in this appendix. The first is a simplified approach for small
dischargers only. If this method is applicable, then a small discharger
need not perform dissolved oxygen calculations dependent on settled effluent
suspended solids accumulations. The second prediction method is applicable
for both small and large dischargers.
SMALL DISCHARGER APPROACH
Two types of problems (dissolved oxygen depletion and biological
effects) and two types of receiving water environments (open coastal and
semi-enclosed bays or estuaries) are considered in the following approach.
Figure B-l is to be used for open coastal areas that are generally
considered well flushed. The dashed line represents combinations of solids
mass emission rates and plume heights-of-rise that would result in a steady-
state sediment accumulation of 50 g/m2. Review of data from several open
coast discharges has indicated that biological effects are minimal when
accumulation rates were estimated to be below this level. Consequently, if
the applicant's mass emission rate and height-of-rise fall below this dashed
line no further sediment accumulation analyses are needed. Applicants whose
charge characteristics fall above the line should conduct a more detailed
analysis of sediment accumulation discussed in the following section.
The solid line in Figure B-l represents a combination of mass emission
rates and plume heights-of-rise that were projected to result in sufficient
sediment accumulation to cause a 0.2 mg/L oxygen depression. Applicants
whose discharge falls below this solid line need not provide any further
analysis of sediment accumulation as it relates to dissolved oxygen.
B-2
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7000 r-
6000
I
» 5000
(ft
9
ui
4000
3000
2OOO
1000
I
024 6 6 1O 12 14 16 18 20
HEIGHT OF RISE, m
STEADY STATE SEDIMENT ACCUMULATION LESS THAN 50g/m2
DO DEPRESSION DUE TO STEADY-STATE SEDIMENT
DEMAND > 02 mg/l
R«f«r»rx»: Tetra Tech (1982).
Figure B-1. Projected relationships between suspended solid mass
emission, plume height-of-rise, sediment accumulation,
and dissolved oxygen depression for open coastal areas.
B-3
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Figure B-2 should be used in a similar manner for discharges to semi-
enclosed embayments or estuaries. Because estuaries and semi-enclosed
embayments are potentially more sensitive than open coastal areas, the
critical sediment accumulation was set at 25 g/m?.
Methods described in Tetra Tech (1982) were used to determine the mass
emission rates and heights-of-rise resulting in the sediment accumulation
rates specified above. In order to use these methods, several assumptions
were made. A current velocity of 5 cm/sec was assumed for the open coastal
sites and a velocity of 2.5 cm/sec was assumed for the semi-enclosed
embayments. these velocities are conservative estimates of average current
velocities over a 1-yr period. The settling velocity (Vs) distribution used
is considered typical of primary or advanced primary effluents and is shown
below:
5 percent have Vs > 0.1 cm/sec
20 percent have Vs > 0.01 cm/sec
30 percent have Vs > 0.006 cm/sec
50 percent have Vs > 0.001 cm/sec
The remaining solids settle so slowly that they are assumed to remain
suspended in the water column indefinitely. The effluent is considered to
be 80 percent organic and 20 percent inorganic. The above distribution is
based on the review of data in Section 301 (h) applications and other
published data (Myers 1974; Herring and Abati 1978).
The annual suspended solids mass emission rate should be calculated
using the average flow rate and an average suspended solids concentration.
The plume height-of-rise, determined previously in the initial dilution
calculation, or 0.6 times the water depth, whichever is larger, should be
used to enter the appropriate figure (Figure B-l or B-2).
B-4
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4000 r-
0 3000
o
(A
o
uj 2000
cc
I
M 1000
(A
55
6 8 10 12 U 16
HEIGHT OF RISE, m
20
STEADY STATE SEDIMENT ACCUMULATION LESS THAN 250/m2
DO DEPRESSION DUE TO STEADY-STATE SEDIMENT
DEMAND > 0.2 mg/l
Reference: Tetra Tech (1982).
Figure B-2. Projected relationships between solid mass emission, plume
height-of-rise, sediment accumulation, and dissolved oxygen
depression for semi-enclosed embayments and estuaries.
B-5
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LARGE DISCHARGER APPROACH
The approach described here considers the processes of sediment
deposition, decay of organic materials, and resuspension. However, the
strictly quantitative prediction of seabed accumulation is based only on the
processes of deposition and decay. Because resuspension is not evaluated
easily using simplified approaches, the analyses described in this chapter
consider resuspension separately and in a more qualitative manner that is
based on measured near-bottom current speeds in the vicinity of the diffuser.
Data Requirements
To predict seabed deposition rates of suspended solids, the following
information is required:
• Suspended solids mass emission rate
• Current speed and direction
• Height-of-rise of the plume
• Suspended solids settling velocity distribution.
The mass emission rate, M (kg/day), is:
M = 86.4(S)(Q) B-l
where:
S » Suspended solids concentration, mg/L
Q - Volumetric flo* rate, m3/sec.
It is suggested that the applicant develop estimates of the suspended
solids mass emission rate for the season (50-day period) critical for seabed
B-6
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deposition and for a yearly period. If the applicant anticipates the mass
emission rate will increase during the permit term, the mass emission rate
at the end of the permit term should be used.
Current-speed data are needed to determine the distance from the
outfall that the sediments will travel before accumulating on the bottom.
Consequently, depth-averaged values are best, if available. Otherwise,
current speeds near mid-depth may be sufficient. The following current data
are needed for the assessment:
• Average value upcoast, when the current is upcoast
• Average value downcoast, when the current is downcoast
• Average value onshore, when the current is onshore
• Average value offshore, when the current is offshore.
If no current data are available, values of 5 cm/sec for longshore transport
and 3 cm/sec for onshore-offshore transport have been found to be reasonable
values.
Plume trapping levels representative of the critical 90-day period and
of the annual cycle are needed. The applicant should use density profiles,
effluent volumetric flow rates, and ambient currents characteristic of these
time periods. Extreme values should not be used. Usually the annual
average and critical 90-day average flow rates and current speeds (in the
predominant current direction) should be used. The expected average plume
heights-of-rise above the seafloor should be determined using available
receiving water density profiles. If large numbers of profiles exist for
each month (or oceanographic season), then the applicant could compute the
plume height-of-rise above the seafloor for each of the available profiles,
and then average the heights. If relatively few profiles are available for
each month, then the applicant could compute the plume height of risk for
each profile and use the lowest height-of-rise as the average. The monthly
B-7
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average heights of rise can then be used to compute the average height-of-
rise for annual and critical 90-day periods. If so few profiles exist that
it is not possible to determine whether differences exist between months (or
oceanographic seasons), then the applicant should use the lowest plume
height-of-rise (based on calculations using the average effluent flow and
current speed) as the average height-of-rise for both the annual and
critical 90-day periods.
If the applicant has not determined a suspended solids settling
velocity distribution, the following can be used based on data from other
Section 301(h) applications:
Primary or Advanced Primary Effluent Raw Sewage
5 percent have Vs >0.1 cm/sec 5 percent have Vs >1.0 cm/sec
20 percent have Vs >0.01 cm/sec 20 percent have Vs >0.5 cm/sec
30 percent have Vs >0.006 cm/sec 40 percent have Vs >0.1 cm/sec
50 percent have Vs >0.001 cm/sec 60 percent have Vs >0.01 cm/sec
85 percent have Vs >0.001 cm/sec.
The remaining solids settle so slowly that they are assumed to remain
suspended in the water column indefinitely (i.e., they act as colloids).
Consequently, 50 percent of the suspended solids in a treated effluent and
85 percent of those in a raw sewage discharge are assumed to be settleable
in the ambient environment.
Prediction of Deposition
Although a portion of the settled solids is inert, primary concern is
with the organic fraction of the settled solids. For purposes of this
evaluation, composition of the waste discharge can be assumed to be as
fol1ows:
B-8
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• 80 percent organic and 20 percent Inorganic, for primary or
advanced primary effluent
• 50 percent organic and 50 percent inorganic, for raw sewage.
Accumulation should be predicted for the critical 90-day period when
seabed deposition is likely to be highest and for steady-state conditions
where average annual values are used. The results should be presented in
graphical form, as shown in Figure B-3. Supporting tables should be
submitted with the application. The applicant must exercise judgment when
developing the contours, especially when accounting for rapid depth changes
offshore. Sediment contours should be expressed in units of g/m?, not as an
accumulation depth.
An applicant may use a proprietary or publicly available sedimentation
model. Two widely known models are those of Hendricks (1987), which has
been used extensively offshore of Palos Verdes Peninsula in the Southern
California Bight, and Farley (Tetra Tech 1987), which describes the Ocean
Data Evaluation System (ODES) model DECAL. The model DECAL is publicly
available through the U.S. EPA. A simple model is described herein. It can
be used to obtain acceptable estimates of sediment accumulation in a variety
of environments. If its use results in sediment accumulations that lead to
violations of state standards or federal criteria for receiving water
quality, an applicant may use a more sophisticated effluent sediment
accumulation model that better simulates the marine environment.
The method described below assumes that effluent sediment particles
having a specific particle fall velocity settle uniformly within an
elliptical area. This area depends on the plume height-of-rise relative to
the seafloor (not the port depth), the particle fall velocity, and the
average currents speeds in four directions (upcoast, downcoast, onshore, and1
offshore) appropriate for an effluent wastefield at the plume height-of-rise.
For the following sample calculations, the diffuser was assumed to be a
point source. Use of this assumption may not produce reasonable estimates of
sediment accumulation if the diffuser is long. If the diffuser is long,
B-9
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180
o i
I i l nautical mites
I I i kilometers
o 2
CONTOURS IN FEET
Figure B-3. Examples of predicted steady-state sediment accumulation
around a marine outfall.
B-10
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then estimates of the sediment accumulation from each diffuser port can be
summed to obtain an estimate for the entire diffuser. This sum is approxi-
mately the same as that obtained from assuming that the sediment accumulation
area is a ZID-like area (with ends the same as the similar elliptical halves
computed for a single point discharge) and that the effluent suspended
solids having the specific particle fall velocity uniformly settle in this
area. The sediment accumulation due to the entire discharge is the sum of
the accumulations for each particle fall velocity modeled.
To begin computations for a discharge at a point location, the
applicant can create a table similar to Table B-l, showing the amount of
organic solids that settle within each settling velocity group, and the
maximum distance from the outfall at which each group settles. If the
applicant has current data for more than four quadrants, those data can be
used. The maximum settling distances for each group in each direction are
calculated using the formula shown in the footnote of Table B-l.
With a sufficiently detailed map (e.g., a NOAA bathymetric chart), each
point DI through 0^5, or Rj through R2Q> can be plotted with the center of
the diffuser as the reference point. Depositional contours are formed by
the four points that define the perimeter of a depositional field (e.g.,
0^0304). The applicant should join these points by smooth lines, so that
the contours are elliptically shaped. If the applicant has current data at
60° or 30° intervals, instead of the 90° intervals used here, then the
contours could be created more accurately.
The deposition rates corresponding to each contour are determined as
follows. First, predict the deposition rate within each contour due to each
individual settling velocity group, as shown in Table B-2. This quantity
is Mi/A-j, or the group deposition rate divided by the area within the
contour. The area within any contour is a function of the four points
(e.g., DJ, 02, 03, and 04), and is denoted in the table by f(0^20304). A
planimeter is probably the most accurate method of finding the area. Once
the deposition rates by group have been found, then the total deposition
rate can be calculated by summing all contributing deposition rates. For
B-ll
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TABLE B-1. EXAMPLE TABULATIONS OF SETTLEABLE ORGANIC COMPONENT
BY GROUP, AND MAXIMUM SETTLING DISTANCE BY GROUP
Mass Emission Rate • MT
Organic Component * Mo »
Percent by Settling
0.8 My, for primary effluent
0.5 MJ., for raw effluent
Organic Component
Maximun Settling Distance from Outfall*
Velocity Group
Primary Effluent
5 (V, > 0.1 cm/sec)
15 (V * 0.01 cm/sec)
10 (V, a 0.006 cm/sec)
20 (V « 0.001 cm/sec)
by Group
0.04 MT
0.12 M}
0.08 MT
0.16 Hj
Upcoast
o1
°5
D13
Oowncoast
D6
D14
Onshore Offshore
D15 °16
Sum » 0.40 MT
Ran Sewage
10
10
20
20
25
(Vs
s
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TABLE B-2. EXAMPLE TABULATIONS OF DEPOSITION RATES AND ACCUMULATION RATES BY CONTOUR
Organic Mass Com-
ponent by Group
Primary Effluent
0.04 MT = M1
0.12 MT * M2
0.08 HT = Mj
0.16 MT = M4
Raw Sewage
a, 0.05 MT = M1
£ 0.05 MT = M2
o.io MT = MJ
0.10 MT = M4
0.125 MT = Mj
Bottoa Area
A1 ' f(D102D3D4>
A2 " f(05°6W
A4 ' f(D13014D15D16)
A, - ftR^R,)
A3 " f(R9R10R11R12}
A4 = f(R13R14R15R16>
A5 = f(R17R18R19R20)
Mass Deposition Total Organic Deposition Rate
Rate, by Group within Area (g/r/yr)
Mj/A, M^yM-j/A^Mj/Aj^ - f,
H / A_ M_ /A_^M /A • f
H4/A4 M4/A4 » f4
M^A, M1/A1*M2/A2*M3/AJ*M4/A4*M5/A5 - f,
1* ""• "I* T A* A "C' C *X
N/B\ U /A ttt /A B 4
/ ' "/ / * A^^C*"C A
M5/A5 VA5 " f5
Accumilation (a/i/)
Steady-State 90 Day
f« fl
j1 jj1 I1-wp(-90k^]
ri r^ [1-exp(-90kJ]
"d Kd ff
Note: Units of ff are g/o^/day.
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example, the innermost contour receives contributions from all groups,, while
the outermost contour receives a contribution only from one group.
So far, only the rates of organic deposition (in units of g/m2/yr) have
been predicted. The accumulation of the organic material (S^) can be
predicted by Including decay as follows:
, fi
S^ (g/mz) » r1 , at steady state
*d
B-2
Si (g/m2) - J- [1 - exp (-90 kd)], for 90 days.
d
The f-j are the deposition rates in units of g/m2/day, as contrasted to the
units of g/nrVyr in Table B-2. The decay rate constant, kj, has a typical
value of 0.01/day. For example, if the organic deposition rate for annual
conditions is 100 g/m2/yr, the steady-state accumulation is:
100
If the organic deposition rate for the critical 90-day period is 300 g/m^/yr,
the 90-day accumulation is:
300 g/m2/yr x 36* ^ys x 0>0i/day x [1-exp (-90 x 0.01)] = 49 g/m2. B-4
This example shows that Input data for the 90-day and steady-state accumula-
tions are different. Consequently, Tables B-l and B-2 should each be
completed twice. Also the accumulation over a critical 90-day period can
exceed the steady-state accumulation. This is caused by short-term
deposition rates that are considerably higher than the long-term average.
In the example, the maximum 90-day deposition rate of 300 g/m2/yr would
eventually decrease to values below 100 g/m^/yr, so that on a yearly basis
the deposition rate is 100 g/m2/yr.
B-14
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B-II. DISSOLVED OXYGEN CONCENTRATION FOLLOWING INITIAL DILUTION
When wastewater is discharged through a single port or a diffuser, the
effluent forms a buoyant plume that entrains ambient water as it rises.
Because the initial dilution process occurs rapidly (i.e., on the order of
minutes), BOD exertion (a relatively slow process) is negligible during this
period. However, an immediate dissolved oxygen demand (IDOD), which
represents the oxygen demand of reduced substances that are rapidly
oxidized (e.g., sulfides to sulfates), might not be negligible. The
dissolved oxygen concentration following initial dilution can be predicted
using the following expression:
D0f - D0a + (D0e - IDOD - D0a)/Sa B-5
where:
DOf » Final dissolved oxygen concentration of receiving water at the
plume trapping level, mg/L
D0a * Affected ambient dissolved oxygen concentration immediately
upcurrent of the diffuser averaged over the tidal period (12.5 h)
and from the diffuser port depth to the trapping level, mg/L
D0e * Dissolved oxygen of effluent, mg/L
IDOD - Immediate dissolved oxygen demand, mg/L
Sa = Initial dilution (flux-averaged).
The applicant should use the least favorable combination of values for
effluent dissolved oxygen, IDOD, affected ambient dissolved oxygen, and
initial dilution. The effluent dissolved oxygen concentration at the point
B-15
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of discharge from the treatment plant is often 0.0 mg/L. Because the
critical case Is desired, a concentration of 0.0 mg/L Is a reasonable
value. However, If data show that dissolved oxygen concentrations In the
effluent are greater than 0.0 mg/L during the critical periods, then these
data may be used.
The IDOD values typically vary from 0 to 10 mg/L, but can be higher
depending on the level of treatment and presence of Industrial flows.
Table B-3 can be used to select reasonable IDOD values. Alternatively, the
IDOD can be measured as discussed below. The Influence of the effluent IDOD
on ambient dissolved oxygen can be estimated from the following table
(calculated as -IDOD/Sa):
Contribution of IDOD to Lowering of DOf (mg/L)
Initial Dilution
IDOD (mg/L)
1
2
5
10
20
At high initial dilutions, the IDOD contribution is small. Thus, the
expense of laboratory tests may be unwarranted. If IDOD is to be determined
experimentally, the procedures in Standard Methods (American Public Health
Association 1985, p. 530) should be generally followed except that the
dilution water should be seawater from the discharge site instead of
distilled water, and the effluent sample should be incubated anaerobically
for a length of time equal to the travel times from the plant through the
diffuser for minimum, average, and maximum flow conditions. The effluent
sample should be mixed with the dilution water after incubation. The
dissolved oxygen concentration of the effluent and dilution water should be
measured separately after incubation and before mixing the samples. The
dissolved oxygen of the mixture should be measured 15 min after preparation.
B-16
10
-0.1
-0.2
-0.5
-1.0
-2.0
30
-0.03
-0.07
-0.17
-0.33
-0.67
50
-0.02
-0.04
-0.1
-0.2
-0.4
100
-0.01
-0.02
-0.05
-0.10
-0.20
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TABLE B-3. TYPICAL IDOD VALUES
Treatment Level
Untreated or less
than primary
Primary
Advanced primary
Effluent
BODs, mg/L
50-100
50-100
50-100
100-150
100-150
100-150
150-200
150-200
150-200
<50
<50
Travel Time, mina
<60
60-200
200-300
>300
0-100
100-300
>300
0-100
100-300
>300
0-100
100-300
>300
0-60
>60
IDOD, mg/L
5
10
15
20
2
3
4
3
4
5
5
7
8
0
1
a Travel time should include the total travel time from the treatment plant
through the diffuser, including any land portion of the outfall.
Note: Information compiled from 301(h) applications.
B-17
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The IDOD Is calculated using the following equation:
(DOD)(PD) + (S)(PS) - DOM
IDOD B B 5 * H B-6
s
where:
IDOD « Immediate dissolved oxygen demand, mg/L
DOp » Dissolved oxygen of dilut :>n water (seawater), mg/L
Pp - Decimal fraction of dilution water used
S " Dissolved oxygen of effluent after incubation, mg/L
PS » Decimal fraction of effluent used
D0|yj = Dissolved oxygen of mixture after 15 min, mg/L.
Several dilutions should be used, preferably close to the actual initial
dilution, unless the difference between the initial and mixed concentrations
is less than 0.1 mg/L. All data used in the above calculations, the
incubation times, and the computed results for each test should be included
in the application.
The lowest initial dilution (flux-averaged) should be used for the
final dissolved oxygen calculation. Usually, this dilution will correspond
to the maximum flow rate at the end of the permit term. Low initial
dilutions can also occur at smaller effluent flow rates if stratification is
sufficiently severe. Typically, dilutions Huring periods of maximum
stratification should be used for the final dissolved oxygen calculation.
The affected ambient dissolved oxygen concentrations should also
represent critical conditions. Usu y, critical conditions will occur
B-18
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during the maximum stratification period in the late summer or in the spring
when upwelling of deep ocean water occurs. For existing discharges, the
affected ambient data should be collected at locations directly upcurrent of
the diffuser, thereby incorporating the potential effects of recirculation.
For proposed new or relocated discharges, affected ambient dissolved oxygen
levels upcurrent of the diffuser should be estimated from mathematical
models of the discharge or by extrapolation from similar situations.
Dissolved oxygen data, as well as any ambient water quality constituent, may
be averaged between the depth of the discharge ports and the plume trapping
level, which corresponds to the lowest initial dilution that was used to
predict the final dissolved oxygen concentrations. If applicants use a
mathematical model that allows multiple vertical levels of input for ambient
water quality instead of an average value, this should be noted.
The time period over which ambient data may be averaged may depend on
specifications of intensity and duration factors in applicable water quality
standards. For example, if certain numerical values shall not be compromised
over a period of 4 h, a 4-h average of input data may be reasonable. Absent
any more stringent specification in locally applicable standards, an average
over a half tidal cycle (approximately 12.5 h) would provide a generally
conservative estimate.
The affected ambient dissolved oxygen concentration can change
substantially as a function of depth, depending on environmental character-
istics and seasonal influences (e.g., upwelling). As the plume rises during
initial dilution, water from deeper parts of the water column is entrained
into the plume and advected to the plume trapping level. If the dissolved
oxygen concentration is lower in the bottom of the water column than at the
trapping level, the low dissolved oxygen water is advected to a region
formerly occupied by water containing higher concentrations of dissolved
oxygen. The result is an oxygen depression caused by entrainment.
This oxygen depression caused by the waste discharge and associated
entrainment (ADO}) should be computed as the difference between DOf as
B-19
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defined in Equation B-5 and the affected ambient dissolved oxygen concen-
tration at the trapping depth
ADOj - DOf - D0t - D0a - D0t + (D0e. - IDOD - D0a)/Sa B-7
The oxygen depression of the wastefield relative to the trapping depth
expressed in percent is (-
For cases when the effect of entraining low dissolved oxygen water can
be neglected, the oxygen depletion (A002) should be computed as the
difference between the average affected ambient dissolved oxygen concentra-
tion (D0a) in the entrained water and DOf as shown below.
AD02 - DOf - D0a = (D0e - IDOD - D0a)/Sa B-8
The oxygen depletion of the wastefield relative to the average affected
ambient dissolved oxygen concentration is (-AD02/DOa)100.
The equation of Baumgartner (1981) for the percentage depression is:
(DO. - D00 + IDOD)
D0t x S, - * 10° B'9
w a
This equation can be derived by assuming that D0a » DOt in Equation B-7.
Use of Equation B-9 has been allowed in the State of California.
These differences can be described as a percentage of the ambient
concentration or as a numerical difference, depending on the requirements of
the state. In some states, the final dissolved oxygen concentration must be
above a specified limit or must be converted to percent saturation to
determine whether the final concentration is above a prescribed limit.
Dissolved oxygen saturation can be determined as a function of temperature
and salinity using the method of Green and Carritt (1967) and Hyer et al .
(1971) as tabulated in Table B-4. The applicant may want to consult with
B-20
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TABLE B-4. DISSOLVED OXYGEN SATURATION VALUES
Dissolved Oxvaen Saturation. ma/L
Temperature
(° C) 20
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
12.8
12.5
12.1
11.8
11.5
11.3
11.0
10.7
10.5
10.2
10.0
9.6
9.5
9.3
9.1
8.9
8.7
8.6
8.4
8.2
8.1
7.9
7.8
7.7
7.6
7.5
7.4
7.2
7.2
7.1
7.1
22
12.6
12.3
12.0
11.7
11.4
11.1
10.9
10.6
10.3
10.1
9.9
9.6
9.4
9.2
9.0
8.8
8.6
8.5
8.3
8.1
8.0
7.9
7.7
7.6
7.5
7.4
7.3
7.2
7.1
7.1
7.1
24
12.5
12.2
11.9
11.5
11.3
11.0
10.7
10.5
10.2
10.0
9.7
9.5
9.3
9.1
8.9
8.7
8.5
8.4
8.2
8.0
7.9
7.7
7.6
7.5
7.4
7.3
7.2
7.2
7.1
7.0
7.0
Salinity (ppt)
26 28 30
12.3
12.0
11.7
11.4
11.1
10.8
10.6
10.4
10.1
9.8
9.6
9.4
9.2
9.0
8.8
8.6
8.4
8.3
8.1
8.0
7.7
7.7
7.6
7.5
7.4
7.3
7.2
7.1
7.0
7.0
6.9
12.1
11.8
11.5
11.2
11.0
10.7
10.4
10.2
9.9
9.7
9.5
9.3
9.1
8.9
8.7
8.5
8.3
8.2
8.0
7.9
7.7
7.6
7.5
7.4
7.3
7.2
7.1
7.0
7.0
6.9
6.9
12.0
11.7
11.4
11.1
10.8
10.6
10.3
10.1
9.8
9.6
9.4
9.2
9.0
8.8
8.6
8.4
8.2
8.1
7.9
7.8
7.6
7.5
7.4
7.3
7.2
7.1
7.1
7.0
6.9
6.9
6.8
32
11.8
11.5
11.2
10.9
10.7
10.4
10.2
9.9
9.7
9.5
9.2
9.0
8.8
8.7
8.5
8.3
8.1
8.0
7.8
7.6
7.6
7.5
7.4
7.3
7.2
7.1
7.0
6.9
6.9
6.8
6.8
34
11.7
11.4
11.1
10.8
10.5
10.3
10.0
9.8
9.6
9.3
9.1
8.9
8.7
8.5
8.4
8.2
8.0
7.9
7.7
7.6
7.5
7.4
7.3
7.2
7.1
7.0
7.0
6.9
6.9
6.8
6.8
36
11.5
11.2
10.9
10.7
10.4
10.1
9.9
9.7
9.4
9.2
9.0
8.8
8.6
8.4
8.3
8.1
8.0
7.8
7.6
7.5
7.4
7.3
7.2
7.1
7.1
7.0
7.0
6.9
6.8
6.8
6.7
B-21
-------
the state water quality agency to determine whether any other methods are
t
used to determine compliance with the dissolved oxygen standards.
B-22
-------
B-III. FARFIELD DISSOLVED OXYGEN DEPRESSION
Subsequent to initial dilution, dissolved oxygen in the water column is
consumed by the BOD in the wastefield. The effluent BODs after initial
dilution is needed to estimate farfield dissolved oxygen depletion. The
final BODs concentration can be estimated using the following expression:
BODf - BODa + (BODe ' B°Da)/sa B'10
where:
BODf = Final BODs concentration, mg/L
BODa = Affected ambient BODs concentration immediately updrift of the
diffuser averaged over one-half the tidal period (12.5 h) and from
the diffuser port depth to the trapping depth, mg/L
BODe = Effluent BODs concentration, mg/L
Sa - Initial dilution (flux-averaged).
This equation provides an estimate of the total BODs concentration in
the receiving water. The maximum contribution due to the effluent alone can
be determined by dividing the effluent BODs concentration by the initial
dilution. This value is used later to estimate farfield effects of the
effluent. As a critical case, the maximum monthly average effluent BODs
concentration should be used with the (monthly) critical initial dilution.
For existing plants, the previous 12 mo of effluent BODs data is used to
support the selection of a BODs concentration. For proposed or modified
treatment plants where effluent data are not available, monthly average
influent BODs data should be provided along with the range of daily values.
B-23
-------
The average removal efficiency for the new or modified plant is also needed
to compute estimated effluent BODs concentrations.
Three approaches to assessing farfield dissolved oxygen demand are
described below:
• Simplified mathematical models predicting dissolved oxygen
depletions, using calculation techniques that do not require
computer support
• Numerical models predicting dissolved oxygen depletions, using
a computer
• Evaluation of field data, using a data-intensive approach
where dissolved oxygen concentrations are measured in the
water column and compared to ambient concentrations.
Before undertaking any analysis to determine whether farfield BOD
exertion causes a violation of the dissolved oxygen standard, the applicant
should first check to see whether:
DO$TD 1 D0f • BODfu, for critical conditions B-ll
where:
DO$TD • Dissolved oxygen standard
DOf = Dissolved oxygen concentration at the completion of initial
dilution
BODfu a Ultimate BOD at the completion of initial dilution (» BODf x 1.46).
If the above inequality is true, then the discharge will not violate the
dissolved oxygen standard due to BOD exertion and no further analysis of
B-24
-------
farfield BOD exertion Is required. If the Inequality 1s not true, then
further analysis 1s required.
SIMPLIFIED MATHEMATICAL MODELS
Oxygen depletion due to coastal or estuarine wastewater discharges 1s
primarily caused by exertion of BOD, although Increased nutrient levels can
affect oxygen concentrations Indirectly by altering algal photosynthesis and
respiration rates. BOD consists of a carbonaceous component (CBOD) and
nitrogenous component (NBOD). Both components can contribute to oxygen
depletion. CBOD Is often reported as BODs, the 5-day BOD. Before using BOD
to predict oxygen depletion, the applicant should convert It to BOD^, the
ultimate BOD, by the following relationship:
BODL -1.46 BOD5 B-12
A typical decay rate for CBOD Is 0.23/day (base e) at 20° C. A temperature
correction should be made as follows:
kj - 0.23 x 1.047T-20/day B-13
where:
kj - BOD decay rate at temperature T (° C).
NBOO might not always contribute to oxygen depletion. If the applicant
discharges into open coastal waters where there are no other major discharges
in the vicinity, the background population of nitrifying bacteria might be
negligible. Under these circumstances, the NBOD will not be exerted
immediately. In more enclosed estuarine waters, nitrification in the water
column has been documented from numerous water quality studies. Applicants
should analyze the potential impact of NBOD, if they discharge into
estuarine waters.
B-25
-------
NBOD can be estimated based on data for total Kjeldahl nitrogen
concentration (the sum of organic nitrogen and ammonia nitrogen) in the
waste discharge using the following relationships:
NBODL - 4.57 (TKN) B-14
NBOOs - NfiOD|./2.54
where:
TKN - Total Kjeldahl nitrogen
NBODL - Ultimate NBOO
NB005 - 5-day NBOD.
The decay rate of NBOO can be taken as:
kT - 0.10 x 1.047T-20/day B-15
where:
kj - The decay rate at temperature T (° C)
0.10 - The decay rate at 20° C (base e).
Simplified mathematical models are an acceptable alternative to the
more complex numerical models. In the simplest model of oxygen depletion,
the following are generally assumed:
• The wastewater plume is submerged at the completion of
initial dilution for critical conditions (so that direct
reaeration of atmospheric oxygen into the wastefield does not
occur).
B-26
-------
• Oxygen depletion 1s a function of distance from the discharge
and Is caused by carbonaceous oxygen demand and nitrogenous
oxygen demand.
• The wastefield entrains ambient water as a function of travel
time. Lateral dilution Is the predominant mechanism of
entralnment.
If the applicant demonstrates that the plume will always surface, then the
effects of atmospheric reaeration can be included; otherwise they should not
be included.
When applying a model that predicts farfield oxygen depletion, it is
suggested that the applicant plot dissolved oxygen depletion as a function
of travel time so that the behavior of dissolved oxygen concentrations in
the wastefield can be examined to locate minimum values.
Example oxygen depletion curves as a function of travel time are shown
in Figure B-4. The depletion indicated at time, t=0, denotes the depletion
immediately following initial dilution. The dissolved oxygen deficits
plotted in the figure are relative to the ambient concentration, and tend to
approach zero at travel times longer than those shown in the figure.
For the three cases, the maximum deficits occur at the following travel
times:
• 0.0 days for Curve A
• Approximately 0.2 days for Curve B
• Approximately 4.0 days for Curve C.
The primary reason for the difference in magnitude and time of occurrence of
the maximum deficits is the IDOD, which varies from a high of 66 mg/L for
Curve A to 0.0 mg/L for Curve C. When the IDOD is 66 mg/L (a high value,
B-27
-------
1.0 -
0.9 -
0.8 -
0.7 -
2 0.6 -
O
5 0.5-
o
UJ 0.4 —
8 03~
° 0.2 —
0.1 —
0.0
1 2 3
TRAVEL TIME (days)
i
4
CURVE
A
B
C
BOOf
(ultimata)
-------
but one that could be associated with an unusual discharge), the maximum
depletion 1s caused by Initial mixing processes, and not by farfield BOD
exertion. Conversely, when IDOD is 0.0 mg/L, the maximum depletion is
caused by BOD exertion, and occurs at some distance from the discharge.
The simplified farfield oxygen depletion model for coastal waters
suggested herein is based on an approach developed, by Brooks (1960) for
predicting wastefield dilution subsequent to Initial dilution. The
dissolved oxygen concentration in the receiving waters can be expressed as a
function of travel time as follows:
D0f-D0a lfr Lfn
D0(t) - DO + TD a - rf± l-exp(-k t) - Tp1 l-exp(k t) B-16
s s s
where:
D0(t) » Dissolved oxygen concentration in a submerged wastefield as a
function of travel time t, mg/L
D0a = Affected ambient dissolved oxygen concentration immediately
updrift of the diffuser, mg/L
DOf = Dissolved oxygen concentration at the completion of initial
dilution calculated using Equation B-5, mg/L
kc = CBOD decay rate constant
kn = NBOD decay rate constant
Lfc = Ultimate CBOD concentration above ambient at completion of initial
dilution, mg/L
B-29
-------
Lfn - Ultimate NBOD concentration above ambient at completion of initial
dilution, mg/L
Ds - Dilution attained subsequent to initial dilution as a function of
travel time.
The above equation expresses the dissolved oxygen deficit that arises
because of an initial deficit at the completion of initial dilution (D0a-D0f)
plus that caused by exertion of BOD in the water column. The last term in
the above equation estimates the exertion due to NBOD. The dissolved oxygen
deficit tends to decrease at longer travel times as a result of subsequent
dilution and to increase as a result of BOD exertion. Depending on the
particular case being analyzed, one influence can dominate the other over a
range of travel times so that a minimum dissolved oxygen level can occur
either immediately following initial dilution or at a subsequent travel
time, as previously shown in Figure B-4.
To predict farfield oxygen distribution, one must determine the
dilution attained within the wastefield as a function of time following
discharge. For open coastal areas, dilution is often predicted using the
4/3 law (Brooks 1960), which states that the lateral diffusion coefficient
increases as the 4/3 power of the wastefield width. In mathematical form:
B-17
u \ u/
where:
c - Lateral diffusion coefficient,
0 » Diffusion coefficient when L = b
L » Width of sewage field at any distance from the ZID, ft
b » Initial width of sewage field (aporoximately as the longest
dimension of the ZID), ft.
B-30
-------
The initial diffusion coefficient can be predicted from:
e0 - 0.001 b4/3 ft2/sec
Based on the 4/3 law, the center!ine dilution, D$, is given by:
1/erf
where:
Travel time, sec
erf - The error function.
"•*
1/2
B-18
B-19
The 4/3 law is not always applicable, especially in coastal areas or
estuaries. In coastal areas, Grace (1978) suggests that the diffusion
coefficient vary linearly with L. The subsequent dilution can be expressed
as:
1/erf
- 1
1/2
B-20
A more conservative choice is to assume the diffusion coefficient is a
constant. The subsequent dilution can then be expressed as:
1/erf
B-21
B-31
-------
These three equations are cumbersome to use, especially if repeated
f
applications are needed. To facilitate predicting subsequent dilutions,
values of Os as a function of 12e0t/b2 are shown in Figure B-5 for values
of Brooks' n equal to 0, 1, and 4/3. For example, if b - 100 ft, and
t - 9,000 sec (2.5 h), then e0 - 0.464 ft2/sec and 12e0t/b2 - 5.0. Assuming
that Brooks' n - 1, then use of Figure B-5 shows that Ds - 4.3 approximately.
The figure also reveals that the predicted dilutions are substantially
different, depending on the relationship obeyed by the lateral diffusion
coefficient. In some instances, the Brooks' n » 1 law might overestimate
subsequent dilution, even if the outfall is in coastal waters. To attain
the subsequent dilutions predicted at large travel times, a large amount of
dilution water must be available. Because many outfalls, particularly small
ones, are not far from shore, the entrainment rate of dilution water can be
restricted by the presence of the shoreline and the depth of the water. As
the wastefield widens substantially, the rate of entrainment could decrease,
and neither the Brooks' n - 4/3 nor the Brooks' n - 1 law may be obeyed. It
is suggested that applicants be conservative and base subsequent dilution on
a constant lateral diffusion coefficient (i.e., Brooks' n » 0), rather than
the Brooks' n - 1 or Brooks' n » 4/3 laws. However, if the applicant can
show that the 4/3 law (or some other relationship) is applicable to the
discharge site, then that relationship should be used.
If the applicant's discharge is near the mouth of a wide estuary, the
approach just discussed can be used directly to predict oxygen depletion.
If, however, the applicant discharges into a long narrow estuary, then it is
likely that the sides of the estuary will limit the lateral dilution that is
attainable. Under these conditions, the maximum dissolved oxygen deficit
with respect to saturation can be predicted as:
kW
A(k2-k)
B-22
B-32
-------
00
I
CO
co
UJ
C
DC
16 -i
14 -
12 -
10 -
-
6 -
4 -
2 -
n = 4/3
n=1
n = 0
I
3
456
12€«t/B2
i
9
10
Reference: Brooks (1960).
Figure B-5. Farfield dilution as a function of 12 €Qt/B.
-------
where:
0 - Dissolved oxygen deficit
A • Cross-sectional area of the estuary near the discharge site
k - CBOD decay rate constant
kg - Reaeration rate constant
E|_ - Longitudinal dispersion coefficient
U - Mass loading rate of CBOD.
The applicant can predict the deficits due to NBOD by using the appropriate
k and W values and adding the two deficits to get the total. With reasonable
values for the constants, the total dissolved oxygen deficit for discharge
to narrow estuaries becomes:
D - (3.14 Wc + 2.55 Wn) 1
-------
NUMERICAL MODELS
Numerical models are an acceptable method of predicting oxygen
depletion caused by a discharge. Numerical models may consider the combined
effect of farfield demand In the water column, as discussed above, and the
oxygen demand associated with organic sediments. If not, the applicant may
have to augment the numerical modeling analysis to address unanswered
questions associated with sediment oxygen demand.
The applicant should try to Isolate the Impact of the outfall on
dissolved oxygen concentrations by considering that the applicant's discharge
1s the sole source of oxygen depletion In the system being modeled. The
applicant can then predict the dissolved oxygen depletion caused by the
discharge by subtracting the background dissolved oxygen level from those
predicted by the model. This approach also simplifies the applicant's
analysis because data from other wastewater sources are not required.
Specific guidelines can be offered to applicants who choose to use
numerical models. Typically, the most severe dissolved oxygen depletion due
to BOD exertion occurs when the water column is density stratified in the
presence of tidally reversing currents and low nontidal currents, and the
wastefield remains submerged following initial dilution. If such conditions
occur at the applicant's outfall site, then the numerical model should be
layered vertically, with a minimum of two layers. The plume should be
discharged into the bottom layer to simulate the submerged discharge with
the consequence that direct atmospheric reaeration is not present in this
layer.
The applicant should set up the grid system for the numerical model
such that the smallest segments are located in the vicinity of the diffuser
and gradually increase in size with distance from the diffuser. The volume
of the segments in the immediate vicinity of the diffuser should approximate
the volume of the ZID in order to prevent an initial dilution that is
artificially high and that would cause the model to underestimate dissolved
oxygen depletion. The applicant might choose to experiment with grid
B-35
-------
configuration by starting with a coarse grid and then decreasing grid size
until the model results do not significantly change.
A steady-state numerical model will be acceptable for the dissolved
oxygen analysis because dynamic or unsteady analyses are generally more
costly, more difficult to implement, and require more data.. The applicant
•should consider, however, whether intratidal variations can cause more
severe depletions than are predicted by a steady-state model that calculates
average oxygen depletions over a tidal cycle. Slack tide, for example,
might be critical because oxygen-demanding materials can accumulate in the
vicinity of the discharge. For existing discharges, the applicant might
want to augment the steady-state modeling analysis by an abbreviated
sampling program to determine dissolved oxygen depletions during slack-tide
periods within a tidal cycle. Intratidal variations are likely to be more
important in enclosed estuaries than along open coastal areas.
EVALUATION OF FIELD DATA
Extensive field data collection and analysis are required to fully
implement this third approach. Limited samples of water column dissolved
oxygen may be inadequate to demonstrate compliance with standards under
critical conditions. Limited information should be supplemented with
analyses based on numerical or simplified mathematical modeling.
These statements should not discourage applicants from collecting and
submitting dissolved oxygen data from the vicinity of an existing discharge.
To the contrary, such data, if available, should be submitted, particularly
if the Section 301 (h) application is for a current discharge or for an
improved or altered discharge at the same location. However, the data might
reveal only a portion of the impact of the wastefield, for the following
reasons:
• The location of the maximum oxygen depletion might not be
sampled.
B-36
-------
• The sampling program could have been conducted during-a
period that was not critical with respect to the discharge
or receiving water conditions. Critical discharge conditions
are generally associated with high effluent BOD and high
volumetric flow rates. Critical receiving water conditions
are usually associated with minimum initial dilutions
(maximum density stratification), maximum water temperatures,
and possibly slack-tide or low nontidal current conditions.
• Ambient dissolved oxygen concentrations can vary spatially
and temporally for conditions unrelated to the discharge
(e.g., upwelling effects). Consequently, dissolved oxygen
depletions associated with the discharge can be masked by
background variability.
Some applicants might have access to dissolved oxygen demand data
collected adjacent to another outfall at a nearby coastal area and attempt to
use those data to show that their own discharge will not violate dissolved
oxygen standards. This approach can be, but is not always, reliable. The
applicants should include in the application sufficient information such
that the data collection program for the nearby area can be reviewed, and
then show that the predicted dissolved oxygen depletions are the maximum
likely to be produced at the nearby discharge site. The applicant should
also demonstrate that the results of the nearby discharge can be extrapolated
to the applicant's discharge. Essentially, the dissolved oxygen depletion
at the adjacent discharge (due to both BOD utilization and sediment oxygen
demand) will need to be at least as severe as that at the applicant's
discharge.
B-37
-------
B-IV. SEDIMENT OXYGEN DEMAND
The oxygen depletion due to a steady sediment oxygen demand can be
predicted by:
Ann SB XM - a S kd XM
AUO " 86,400 UHD 86,400 UHD
where:
ADO =• Oxygen depletion, mg/L
SB - Average benthic oxygen demand over the deposition area, -g
XM = Length of deposition area (generally measured in longshore
direction), m
H = Average depth of water column influenced by sediment oxygen
demand, measured above bottom, m
U - Minimum sustained current speed over deposition area, m/sec
kd - Sediment decay rate constant, 0.01/day
a = Oxygen:sediment stoichiometric ratio, 1.07 mg 02/mg sediment
S = Average concentration of deposited organic sediments over the
deposition area, g/m2
D = Dilution caused by horizontal entrainment of ambient water as it
passes over the deposition area (always >1).
B-38
-------
Both S and XM can be determined from the analysis performed in the Chap-
ter B-I on "Suspended Solids Deposition." Figure B-4 in that chapter shows
an example plot of seabed deposition. For that example, an appropriate
estimate of S is the average of the maximum and minimum values, or
B-25
The distance XM, measured parallel to the coast and within the 5 g/m2
contour, is 8,000 m.
The depth of water affected by the sediment oxygen demand is not really
a constant value (as suggested by the previous formula) but varies as a
function of the travel time across the zone of deposition. The affected
depth H (in meters) is chosen to represent the average depth influenced by
the sediment oxygen demand and can be estimated as:
*7 u1/2
H = 0.8 I -^rr1] B-26
where:
ez • Vertical diffusion coefficient (cnrVsec).
For the example case where U = 3 cm/sec, XM = 8,000 m, and ez = 1 cm2/sec,
H.0.8x/'*»'0f'"00]1/2xIfe.-4.1. B-27
If the applicant desires to compute a value of vertical diffusivity,
the following empirical expression can be used:
B-39
-------
R 28
B'28
p dz
where:
ez « Vertical diffusion coefficient, cm^/sec
p - Ambient water density, kg/m3 (1,024)
j£ - Ambient density gradient, kg/m*.
The density gradient used should reflect the most severe stratification
condition that is likely to occur during the critical period.
The dilution D that 1s used in Equation B-24 can be found from Table B-5
where the field width is the width of the deposition area. For the
appropriate travel time and field width, the smaller of the two estimates
shown in the table should be used.
In Chapter B-I (Suspended Solids Deposition), the applicant is asked
to compute the long-term accumulation and the critical 90-day accumulation.
Because the critical 90-day accumulation might exceed the long-term average,
the applicant should use the more critical case when predicting sediment
oxygen demand.
Oxygen Demand Due to Resuspension of Sediments
It is more difficult to accurately predict oxygen demand due to
resuspension than due to either farfield BOD decay or a steady sediment
oxygen demand. To simplify the analysis, the approach here considers a
worst-case situation. The amount of sediment to be resuspended is equal to
the critical 90-day accumulation, which is found using the methods discussed
in the above guidance on "Suspended Solids Deposition."
B-40
-------
TABLE 8-5. SUBSEQUENT DILUTIONS* FOR VARIOUS INITIAL FIELD WIDTHS AND TRAVEL TIMES
Travel
Time (h)
0.5
1.0
2.0
4.0
8.0
12
24
48
72
96
Initial Field Width (ft)
10
2.3/5.5
: " 3.1/13
4.3/32
6.1/85
8.5/>100
10/>100
15/>100
21/>100
26/>100
29/>100
50
1.5/2.0
2.0/3.9
2.7/8.5
3.7/21
5.2/53
6.3/95
8.9/>100
13/>100
15/>100
18/>100
100
1.3/1.6
1.6/2.6
2.2/5.1
3.0/11
4.1/29
5.1/50
7.1/100
10/>100
12A100
14/>100
500
1.0/1.1
1.2/1.3
1.4/1.9
1.9/3.5
2.5/7.3
3.0/12
4.2/30
5.9/80
7.3/>100
8.4/>100
1,000
1.0/1.0
1.1/1.1
1.2/1.5
1.5/2.3
2.0/4.4
2.4/6.8
3.4/16
4.7/41
5.8/73
6.6/100
5,000
1.0/1.0
1.0/1.0
1.0/1.0
1.1/1.2
1.4/1.7
1.6/2.3
2.1/4.4
2.8/10
3.4/17
3.9/24
* The dilutions are entered in the table as N^/tU, where N1 is the dilution assuming a constant diffusion
coefficient, and M2 is the dilution assuming the 4/J law.
B-41
-------
For the material to remain suspended, the ambient current speed has to
be sufficiently great that the volume of water containing the resuspended
material increases over time as ambient water is entrained. It is assumed
that this process continues for up to 24 h.
The applicant should compute the oxygen depletion as a function of time
during this period. This can be done using the following relationship:
S /-krt\
ADO - p£ [l-expl-2f-l] B-29
where:
ADO = Oxygen depletion, mg/L
Sr - Average concentration (in g/m2) of resuspended organic sediment
(based on 90-day accumulation'
H = Depth of water volume containing resuspended materials, m
kr = Decay rate of resuspended sediments, O.I/day
t = Elapsed time following resuspension, h (t varies from 0 to 24 h)
D * Dilution as defined previously (generally set equal to 1).
The variable H is a function of travel time and can be predicted from:
H = (3,600 t e1/2 B-30
where:
e' = Vertical diffusion coefficient when resuspension is occurring
(5 cm2/sec)
t = Elapsed time following resuspension, h.
B-42
-------
The applicant should check to be sure that H does not exceed the water
depth. If it does, set H equal to the water depth.
The concentration of resuspended sediments Sr can be approximated as
the average concentration over the width of the zone of deposition. This
can be determined directly from the contour plots of sediment accumulation,
developed in response to the guidance on "Suspended Solids Deposition" in
Chapter B-I.
The applicant should calculate ADO for 3-h increments for a period of
up to 24 h. The results can be tabulated as shown below. Data and
calculations should be included in the application.
t fhl DO fma/Ll
0 0
3
6
9
12
15
18
21
24 predictions
Most often, a maximum depletion will occur somewhere in the 24-h period, with
depletions decreasing for larger travel times.
B-43
-------
B-V. SUSPENDED SOLIDS CONCENTRATION FOLLOWING INITIAL DILUTION
The concentration of suspended solids at the completion of Initial
dilution should be calculated using the following equation:
SS - SSa
SSf = SSa + —^ a B-31
where:
SSf - Suspended solids concentration at completion of initial dilution,
mg/L
SSa - Affected ambient suspended solids concentration immediately
upcurrent of the diffuser averaged over one-half the tidal period
(12.5 h) and from the diffuser port depth to the trapping level,
mg/L
SSe =» Effluent suspended solids concentration, mg/L
Sa = Initial dilution (flux-averaged).
The maximum change, AS, due to the effluent can be computed as follows:
AS = SSe/Sa B-32
where the terms are as defined above. Equation B-32 is appropriate as long
as the effluent suspended solids concentration is much greater than the
background concentration. During spring runoff in some estuaries, the
background suspended solids concentration may exceed the effluent concentra-
tion. In these cases, the final suspended solids concentration will be
below the background concentration.
B-44
-------
U.S. EPA requires data for periods of maximum stratification and for
other periods when discharge characteristics, oceanographic conditions, water
quality, or biological seasons indicate more critical situations exist. The
critical period generally occurs when water quality standards are most
likely to be violated. If the standard is expressed as a maximum numerical
limit, the critical period would be when the background concentrations are
highest and the initial dilution is low. If the standard is expressed as a
numerical difference from background, the critical period would be when
effluent concentrations are high and initial dilution low. When the
standard is expressed as a percent difference from background, the critical
period could occur when background concentrations are low.
Because effluent suspended solids concentrations can vary with
discharge flow rate, the concentration at the completion of initial dilution
should be computed for the minimum, average dry- and wet-weather, and maximum
flow rates, using the associated suspended solids concentration. The range
and average effluent concentrations should be provided in the application by
month, unless locally applicable standards require compliance over shorter
durations. This information should be available from operating records.
The selection of an appropriate background suspended solids concentra-
tion may be difficult due to a general lack of data. A common problem for
coastal sites is that measurements may be available only at the mouths of
large rivers. Concentrations are often higher at such locations than
farther offshore because of the solids contribution from runoff. Selected
values of background suspended solids concentrations are shown in Table B-6.
Suspended solids background data should be obtained at control stations, at
the ZID boundary of the existing discharges, and at stations between the
ZID-boundary and control stations. Data should be collected over the tidal
cycle and at several depths so the average concentration over the height-of-
rise of the plume over the tidal cycle can be calculated. This value should
be used in Equation B-31.
B-45
-------
TABLE B-6. SELECTED BACKGROUND SUSPENDED SOLIDS CONCENTRATIONS
Suspended Solids
Water Body Concentration* mg/L
Cook Inlet, AK 250-1,280
Southern California Bight 0.7-60
Pacific Ocean near San Francisco, CA 1-33
Broad Sound, MA 18.6-25.2
Massachusetts Bay near South Essex 1.2-30.5
New Bedford Harbor, MA 0.4-6.1
East River, NY 6.0-25.6
Ponce, PR (near shore) 13.5
Puget Sound, WA 0.5-2.0
Outer Commencement Bay, Tacoma, WA 33-51
Commencement Bay near Puyallup River, WA 23-136
Tacoma Narrows, WA 33-63
Note: Data are from 301(h) applications.
B-46
-------
Compliance with the water quality standard can be determined directly
if the standard is expressed in the form of suspended solids concentrations.
If only a general standard exists, the maximum increase due to the effluent
should be computed. If the increase is less than 10 percent, then no
substantial effect in the water column is likely. However, seabed deposition
could still be substantial depending on the mass emission rate of suspended
solids and ambient currents at the discharge site, and thus should be
evaluated.
The water quality standards may also specify limitations on the level
of suspended solids removal. For example, California has a requirement that
75 percent of the solids entering POTWs must be removed. Compliance with
this standard can be determined by estimating the average removal efficiency
for each month based on the average monthly influent and effluent suspended
solids concentrations. The removal efficiency should be equal to or greater
than the required percentage in all months. The applicant should include
the monthly average influent and effluent suspended solids concentrations
along with the computed removal efficiencies.
B-47
-------
B-VI. EFFLUENT pH AFTER INITIAL DILUTION
The calculation of effluent pH following initial dilution is chemically
more sophisticated than other chemical calculations in this document. This
appendix details the basis for Table 1 in the main text showing the ranges
of probable effluent pH following initial dilution. The method for
calculating effluent pH following initial dilution is described herein,
assuming that all of the required variables are known. These variables
include initial dilution and the temperature, salinity, pH, and alkalinity of
the effluent and the receiving water. Effluent and receiving water
temperature, salinity, and pH are normally measured. The (usually critical)
initial dilution is routinely calculated as part of either the Section
301(h) waiver application process or the Section 301(h) permit renewal
process. However, neither the alkalinity of the receiving water nor that of
the effluent is usually measured. The alkalinity of seawater is relatively
constant, however, at a value of 2.3 meq/L (Stumm and Morgan 1981). The
alkalinity of effluent varies from 0.1 to 6.0 meq/L.
The method described herein predicts pH at the completion of initial
dilution of an effluent-receiving water mixture. Because the initial
dilution process occurs over a short time period, mixing is considered to
occur in a closed system. Also, in stratified receiving waters, the
wastewater plume is often trapped below the surface. Thus, the plume does
not equilibrate with the atmosphere, and carbon dioxide exchange between the
atmosphere and mixture is considered negligible. This method is useful for
the calculation of pH, alkalinity, and total inorganic carbon concentration
in the plume after initial dilution.
The pH of the effluent receiving water mixture is calculated using the
equations for aqueous carbonate equilibrium in a closed system (Stumm and
Morgan 1981). For this condition, the five equations that describe the
relationships between pH, the carbonate species, and alkalinity are:
B-48
-------
[HC03-]/[H2C03*] = K!
[C032-]/[HC03-] - K2
[H+] [OH'] - Kw
Cj - [H2C03*] + [HC03-] + [C032~]
Alkalinity - [HC03-] + 2[C032'] -»- [OH'] - [H+]
B-33
B-34
B-35
B-36
B-37
where:
[H2C03*] » The sum of aqueous C02 and true H2C03 concentrations
CT - Total carbonate concentration.
The carbonate species can also be expressed in terms of ionization fractions
OQ , aj, and ct2:
[H2co3*] = CT OQ
[HC03-] = CT a!
[C032-] = CT a2
B-38
B-39
B-40
where:
-i
-i
B-41
B-42
B-49
-------
i+i 2 ru+
+ 1
-1
B-43
Substituting the hydroxide-hydrogen ion relationship and ionization
fractions into the alkalinity equation yields:
Alkalinity - CT (a, + 2a,) + —7- - [H*] B-44
' l ^ +
Because total carbonate is conserved and oj and og are functions solely of
pH, the above equation has only one variable: hydrogen ion concentration.
The model solves the equation to determine the pH of the effluent-receiving
water mixture. The steps involved in the calculations are listed below:
• Determine input data
• Calculate ion product of water, Kw, and carbonate dissociation
constants, Kj and l<2, of the effluent and receiving water
based on temperature and salinity data
• Check consistency between alkalinity and pH of both effluent
and receiving water
• Calculate total carbonate in effluent and receiving water
separately
• Calculate total carbonate, alkalinity, salinity, and
temperature of the effluent-receiving water mixture following
initial dilution (based on proportions of effluent and
receiving water)
• Calculate Kw, Kj, and K£ for the effluent-receiving water
mixture following initial dilution
B-50
-------
• Use a stepping procedure to find pH based on the computed
values for total carbonate and alkalinity of the effluent-
receiving water mixture
• Record results.
The ion product and dissociation constants are calculated for the appropriate
temperature and salinity based on the equations given below. The equations
for the receiving water have been revised so that salinity (in ppt) can be
used.
For effluent:
M07.7 + 0.03279T - 14.8435 (Kelts and Hsu 1978, p. 300) B-45
pK2 - *<9°2'4 + 0.02379T - 6.498 (Kelts and Hsu 1978, p. 300) B-46
A 471 n
pKw = ' j + 0.01706T - 6.0875 (Stumm and Morgan 1981, p. 127) B-47
For receiving water and the effluent-receiving water mixture:
pKj = 3l4°4'7 + 0.03279T - 14.712 - 9.1575S1/3 B-48
(Stumm and Morgan 1981, p. 205)
pK2 = 2t9°2'4 + 0.02379T - 6.471 - 0.3855S1/3 B-49
(Stumm and Morgan 1981, p. 206)
3l441'° + 2.241 - 0.0925S1/2 B-50
(Dickson and Riley 1979, p. 97)
B-51
-------
where: .
T - Temperature in degrees Kelvin
S - Salinity in ppt.
The receiving water equations are valid for salinities down to about 10 ppt.
B-52
-------
B-VII. LIGHT TRANSMITTANCE
Increased suspended solids concentrations associated with municipal
discharges can cause a decrease in light penetration within the water column.
Reductions in light penetration can result in a decrease in phytoplankton
productivity as well as a reduction in the areal distribution of attached
macroalgae such as kelp. Therefore, several states have enacted regulations
governing the allowable levels of interference with light transmittance.
The evaluation of light transmittance may require the measurement of
one or more water clarity variables and a comparison of values recorded in
the vicinity of the outfall with those recorded in control areas. Variables
that are widely measured to assess light transmittance include turbidity,
Secchi disc depth, beam transmittance, and downward irradiance. While many
of the state requirements are very specific in terms of the light transmit-
tance measurements, others leave the selection of the sampling methods to
the discretion of the applicant.
Turbidity is a measure of the optical clarity of water, and many
standards are written in terms of Nephelometric Turbidity Units (NTU).
Measurements are made with a nephelometer, which provides a comparison of the
light-scattering characteristics of the sample with a standard reference.
Differences in the optical design of nephelometers can cause differences in
measured values even when calibrated against the same turbidity standard.
For this reason, caution must be exercised when comparing measurements of
turbidity made from different field sampling programs.
A Secchi disc is used to make visual observations of water clarity.
Records of the depth at which the Secchi disc is just barely visible can be
used to make comparisons of light transmittance among sampling sites.
Measurements of Secchi disc depth are probably the most widely used means of
estimating light penetration. The Secchi disc is easy to use, is accurate
B-53
-------
over a wide range of conditions, and can be used to estimate the attenuation
coefficients for coll 1mated and diffuse light and, therefore, to estimate
the depth of the euphotlc zone. However, since a wastewater plume may be
held below the upper regions of this zone during periods of stratification,
Secchi disc measurements may not be appropriate under all conditions.
Beam transmlttance 1s measured with a transmlssometer and 1s a measure
of the attenuation of a co Hi ma ted beam of artificial light along a fixed
path length (usually 1m). The attenuation Is caused by suspended and
dissolved material as well as the water Itself. These measurements,
therefore, provide Information about both the absorption and scattering
properties of the water. The attenuation of a collimated beam of light In a
water path Is described by the Beer-Lambert law:
Td = e'*1 B-51
where:
T(j » The proportion of light transmitted along a path of length d, m
a - Light attenuation coefficient, m"*.
Measurements of beam transmittance are made in situ at any depth.
The intensity and attenuation of daylight penetration are measured with
an irradiance meter, which utilizes a photovoltaic cell to record incident
light levels. Measurements are made just below the surface and at selected
depth intervals throughout the water column so that light attenuation over
specific depths can be determined. Unlike beam transmittance measurements,
irradiance measurements are influenced by sunlight as well as surface
conditions.
Empirical relationships can be derived among the light transmittance
variables measured by these methods, which permits the estimation of one
based on recorded values of another. These values can also be predicted
B-54
-------
from suspended solids concentrations. The derivation of these relationships
from existing data, in some instances, may be sufficient to allow for the
demonstration of compliance with state standards. Existing data can also be
used to predict the transparency characteristics in the vicinity of an
improved- discharge. Alternatively, a sampling program can be designed to
assess compliance with light transmittance standards based on such empirical
relationships.
Where standards are written in terms of maximum allowable turbidity or
turbidity increase, predicted turbidity in the receiving water at the
completion of initial dilution can be used to demonstrate compliance. By
treating turbidity as a conservative variable, the turbidity in the
receiving water at the completion of initial dilution can be predicted as:
Tf - T. +
where:
Tf = Turbidity in receiving water at the completion of initial dilution,
typically NTU or Jackson Turbidity Units (JTU)
Ta = Ambient or background turbidity
Te - Effluent turbidity
Sa - Initial dilution.
Initial dilution can be predicted based on the methods presented in
Appendix A. Equation B-52 can be used, then, to directly evaluate compliance
with standards written in terms of maximum allowable turbidity or a
turbidity increase.
Laboratory experimental work can also be used in lieu of field sampling
to demonstrate compliance with standards written in terms of an allowable
B-55
-------
turbidity Increase. These analyses consist of determining the turbidity of
a seawater- effluent mixture prepared in the same proportions corresponding
to the predicted concentrations following initial dilution. Experiments
should be conducted to simulate worst-case conditions. Simulations of
expected receiving water turbidity should be made for periods of highest
effluent turbidity (greatest suspended solids concentrations) as well as
lowest initial dilutions. Values of the initial turbidity of the seawater,
the effluent mixture, and the simulated dilution should accompany all test
results.
By deriving a relationship between turbidity and Seech i depth and
utilizing the method of prediction for turbidity in the receiving water
following initial dilution (Equation B-52), compliance with state standards
written in terms of Secchi depth can be evaluated. Secchi disc and
turbidity can be related in the following manner. Assume that the extinction
coefficient of visible light (a) is directly proportional to turbidity (T)
and inversely proportional to Secchi disc (SD), or:
a = Iq T B-53
and
B-54
where kj and kg are constants which need not be specified since they cancel
out in further calculations. These two relationships have theoretical
bases, as discussed in Austin (1974) and Graham (1966). Combining those two
expressions, the relationship between Secchi disc and turbidity becomes:
B-55
When state standards are written in terms of Secchi disc, it is convenient
to combine Equations B-52 and B-55 to yield:
B-56
-------
-i- . -L-
SDf SD, s:
B-56
or
where:
SD.
SD.
-1
B-57
SDf - Minimum allowable Secchi disc reading in receiving water such that
the water quality standard is not violated
SDa - Ambient Secchi disc reading
Sa - Minimum initial dilution that occurs when the plume surfaces
SDe - Critical Secchi disc depth of effluent.
In this manner, the critical effluent Secchi depth (SDe) can be
calculated. An effluent reading higher than this value indicates that
standards will not be violated. This method of predicting the final Secchi
depth in the receiving water can be utilized to provide an estimate of the
effect of the wastewater discharge on the receiving water. This method
should only be used where the standard is exclusively in terms of the
acceptable decrease in the Secchi depth.
Values of the critical effluent Secchi depth (SDe) calculated using
Equation B-57 are presented in Table B-7. In this example, the water
quality standard for the minimum Secchi visibility is 1 m (3.3 ft).
Effluent having a Secchi depth greater than those presented for the selected
ambient conditions and initial dilution will not violate the clarity
standard of the example receiving water. Primary effluents typically have
B-57
-------
TABLE B-7. CALCULATED VALUES FOR THE CRITICAL EFFLUENT SECCHI DEPTH (cm)
FOR SELECTED AMBIENT SECCHI DEPTHS, INITIAL DILUTIONS, AND A WATER
QUALITY STANDARD FOR MINIMUM SECCHI DISC VISIBILITY OF 1 m
Initial
Dilution
10
20
40
60
100
2
18
10
5
3
2
Ambient
3
14
7
4
2
1
Seech 1
4
13
7
3
2
1
Deoth fm)
5
12
6
3
2
1
10
11
6
3
2
1
B-58
-------
Secchi disc values of 5-30 cm (2-12 in). For this case, with an,initial
dilution greater than 40 and an ambient Secchi depth of 2 m (6.6 ft) or
greater, these calculations indicate that the standard would not be violated.
l! Since Secchi disc measurements are made from the water surface
downward, critical conditions (in terms of the Secchi disc standard) will
occur when the initial dilution is just sufficient to allow the plume to
surface. It is notable that maximum turbidity or light transmittance
impacts of a wastewater plume will occur when the water column is stratified,
the plume remains submerged, and initial dilution is a minimum. Under these
same conditions, however, Secchi disc readings might not be altered at all,
if the plume is trapped below the water's surface at a depth exceeding the
ambient Secchi disc depth.
The ability to relate measurements of turbidity to the attenuation
coefficient (a) for collimated light has been demonstrated by Austin (1974).
The attenuation coefficient can be expressed in terms of turbidity as:
a = k x JTU B-58
where:
JTU - Turbidity, JTU
k = Coefficient of proportionality.
Combining Equations B-51 and B-58, turbidity can be expressed as:
-In T.
JTU = kd g B-59
where:
Tj = Fraction of beam transmittance over distance d.
B-59
-------
The coefficient of proportionality (k) takes on values 0.5-1.0. Therefore,
to utilize these relationships for demonstrating compliance with a turbidity
standard based on existing light transmittance data, the value of k must be
determined empirically. This requires simultaneous measurements of beam
transmittance and determination of turbidity covering the complete range of
existing light transmittance records. If data are not available, the "k"
value can be set equal to 1 as a conservative estimate.
, Where a relationship between suspended solids concentration and beam
transmittance data at a particular site can be derived, the suspended solids
concentration at the completion of initial dilution from Equation B-31 can
be used to predict compliance with standards written in terms of light
transmittance.
B-60
-------
B-VIII. OTHER WATER QUALITY VARIABLES
Other variables for which water quality standards may exist include
total dissolved gases, coliform bacteria, chlorine residual, temperature,
salinity, radioactivity, and nutrients. Variables concerned with aesthetic
effects that also may be included are color, floating material, taste and
odor, and hydrocarbons (i.e., grease and oil). For most dischargers,
temperature, salinity, and radioactivity standards are unlikely to be
violated. Aesthetic effects are more likely to occur when the plume
surfaces and the dilution is low. Compliance with aesthetic standards can
best be checked by field observations at the discharge site and along the
shore.
TOTAL DISSOLVED GASES
Several states have a limit for total dissolved gases of 110 percent of
saturation. Supersaturation of dissolved gases is not considered to be a
likely problem for municipal wastewater discharges to the marine environment
and is not discussed further.
CHLORINE RESIDUAL
Chlorine residual standards may be expressed as a concentration limit
in the effluent or as a maximum concentration in the receiving water at
the completion of initial dilution. If the effluent is not chlorinated, no
further information is required. If the standard is expressed as an
effluent limit, chlorine residual data from treatment plant operating
reports, or other sources, should be presented in the application. If no
data are available, then the procedure for chlorination, including the
compound used, quantity, and occurrence of any operational problems, should
be described. If the standard is expressed as a maximum limit at the
B-61
-------
completion of Initial dilution, the concentration in the receiving/water,
assuming the ambient concentration is 0.0 mg/L, can be estimated as follows:
Clf - Cle/Sa B-60
where:
Clf - Chlorine residual at completion of initial dilution, mg/L
Cle - Chlorine residual in effluent, mg/L
Sa - Lowest flux-averaged initial dilution.
As a worst-case approach, the maximum observed chlorine residual in the
effluent should be used with the lowest dilution. If violations are
predicted, the applicable water quality standard may require information on
the frequency of occurrence.
NUTRIENTS
Standards can be expressed as maximum receiving water concentrations of
total nitrogen or total phosphorus or as a general prohibition on amounts
that would cause objectionable aquatic life. In general, for small
discharges when the initial dilution is large, nutrients are not likely to
cause problems. Appropriate state agencies should be contacted to ascertain
if algal blooms, red tides, or other unusual biological activity have
occurred near the discharge site in the past.
Receiving water and effluent nutrient data can be used to estimate
concentrations at the completion of initial dilution. For screening
purposes, the nutrients can be treated as conservative variables. The
concentration is estimated as follows in a similar manner to suspended
solids:
B-62
-------
where:
Ca - Affected ambient concentration Immediately upcurrent of dlffuser,
mg/L
Ce - Effluent concentration, mg/L
Sa • Initial dilution (flux-averaged)
Cf - Concentration at the completion of initial dilution, mg/L.
The predicted concentration can then be compared to the state standard.
Because water quality criteria are often prescribed as maximum values
not to be exceeded following initial dilution, it is useful to rearrange the
above equation to express the maximum allowable effluent concentration as
fol1ows:
(Ce)max - Ca-+ (Sa)min (Cc-Ca) B-62
where:
(Ce)max - Maximum allowable effluent concentration such that water
quality criteria are not exceeded
Cc - Applicable water quality criterion
(Sa)m-jn » Minimum expected initial dilution.
The maximum observed effluent concentration can then be compared to the
predicted allowable concentration. This approach can be used for any
conservative constituent. Thus, if other specific limits exist such as
B-63
-------
for color, effects due to the discharge can be determined as sbown In
Equations B-61 and B-62.
COLIFORM BACTERIA
Standards may exist for total or fecal coliform bacteria or enterococci
and are usually expressed as a mean or median bacterial count and a maximum
limit that cannot be exceeded by more than 10 percent of the samples. If
the effluent is continuously disinfected using chlorination or an equivalent
process, analyses for coliform bacteria may be needed only to verify the
effectiveness of disinfection. If disinfection is done part of the year,
analyses should be representative of conditions when the effluent is not so
treated. The chemicals used, quantities, and frequency of use should be
provided along with a discussion of the reliability of the system.
The coliform bacteria count at the completion of initial dilution due
to the discharge can be estimated as follows:
Bf = Be/Sa B-63
where:
Be - Effluent coliform bacteria count, MPN/100 ml
Sa - Initial dilution.
As a conservative approach, the maximum effluent count and the lowest
initial dilution should be used. If onshore currents occur only during a
particular season, the coliform count at the completion of initial dilution
can be estimated using the lowest initial dilution appropriate for that
season. Effluent coliform data should be submitted to support the appli-
cant's values. The predicted value can be compared with the appropriate
standard at the ZID boundary. This value can also be used to estimate the
bacterial concentration at specific locations away from the ZID.
B-64
-------
Because different limits may apply to specific areas (e.g., shellfish
harvesting areas, beaches, diving areas), the maximum bacterial count at a
specified distance from the discharge may be of concern. This bacterial
count can be estimated in a manner analogous to the estimation of the BOD
exerted as the wastefield spreads out from the ZID. The maximum bacterial
count at the center!ine of the wastefield can be estimated as a function of
distance from the discharge as follows:
Bf ' Ba
Bx - Ba * D^ B'64
where:
Bx - Bacteria count at distance x from ZID, #/100 ml
Ba - Affected ambient bacteria count immediately upcurrent of diffuser,
#/100 ml
Bf » Bacteria count at completion of initial dilution, #/100 ml
Ds = Dilution attained subsequent to initial dilution at distance x
DD = "Dilution" due to dieoff of bacteria caused by the combined
effects of exposure to seawater and sunlight.
when x - 0, Bx =• Bf. In cases where the background bacterial count is
negligible or the effect of the discharge alone is desired, the terms for
the ambient bacterial count can be dropped, simplifying Equation B-64 to:
B
B-65
°* " Ds°b
Values for subsequent dilution as a function of !2e0t/B2 in Figure B-5.
Guidance is included in Chapter B-III ("Farfield Dissolved Oxygen Demand")
B-65
-------
on methods for estimating subsequent dilution for sites located in^ narrow
estuaries or bays.
The decay rate of bacteria in the ocean is influenced by water
temperature, incident light, salinity, and other factors. As a conservative
estimate, the minimum decay rate should be used. If no violations would
occur, then further calculations are not needed. Flocculation and sedimen-
tation can cause an apparent decrease in coliform count in the water column,
but the bacteria are retained in the sediment. Thus, this process is not
included in the above approach. If the applicant has information indicating
that the decay rate at the discharge site should be a different value, the
revised decay rate may be used. The evidence for the revised decay rate,
including any data or results of laboratory tests, should be included in the
application.
In this report, dieoff due to the combined effects of exposure to
saltwater and exposure to sunlight only are considered. The dieoff due to
exposure to saltwater, Dsw, and the dieoff due to exposure to sunlight, Ds],
are (Gameson and Gould 1975):
Dsw = exp(kswt) B-66
Osl =* exp[al(t)] B-67
where:
ksw - Bacteria decay rate due to exposure to saltwater, 1/h
a - Constant, m2/MJ
I(t) = Total intensity of sunlight received by bacteria during the
travel time,
t = Travel time, h.
B-66
-------
The bacteria dieoff due to the combined effects of saltwater and sunlight 1s
Db * Dsw°sl- Gameson and Gould (1975) Indicate that a • 1.24 m2/MJ in situ
for Dorset, England seawater. The total Intensity of sunlight received at
the water surface can be measured, or estimated using site-specific data or
general methods (Wallace and Hobbs 1977). If the wastefleld 1s submerged,
then the calculation of the total sunlight received should reflect the
effect of turbidity on Mght transmission from the sea surface to the top of
the wastefleld. ' --
The bacteria decay rate due to the exposure to saltwater 1s known for
both coliform bacteria and enterococcus bacteria. For coliform bacteria,
ksw - 2.303 exp[(0.0295T - 2.292)2.303] / h B-68
where T - water temperature (° C), based on field measurements at Bridport
(Dorset, England) (Gameson and Gould 1975). The enterococcus bacteria dieoff
rate due to exposure to saltwater is:
ksw - 0.5262 / (24 h) B-69
at a temperature of 20° C (Hanes and Fragala 1967). [It should be noted
that Hanes and Fragala (1967) determined that ksw for coliform bacteria is
0.0424/h at 20° C, a value slightly smaller than the value of 0.0457/h at
20° C based on the formula from Gameson and Gould (1975).]
The estimated coliform count at the location of interest should be
compared to the applicable standard. If a violation is predicted, the water
quality standards may require that the approximate frequency should be
discussed based on the percentage or likelihood of currents transporting the
wastefield in the direction of interest.
B-67
-------
REFERENCES
American Public Health Association. 1985. Standard methods for the
examination of water and wastewater. APHA, Washington, DC. 16th Edition.
1268 pp.
Austin, W.R. 1974. Problems in measuring turbidity as a water quality
parameter. EPA-600/4-74-004. pp. 23-54. In: Proc. on Seminar on
Methodology for Monitoring the Marine Environment.
Baumgartner, D. 1981. Environmental Protection Agency, Office of Research
and Development, presentation at 301(h) Task Force Meeting. 13 March 1981.
Brooks, N.H. 1960. Diffusion of sewage effluent in an ocean current, pp.
246-267. In: Proc. of the 1st International Conference on Waste Disposal
in the Marine Environment, University of California, Berkeley, CA, July
1959. Pergamon Press, Elmsford, NY.
Dickson, A.G., and J.P. Riley. 1979. The estimation of acid dissociation
constants in seawater media from potentiometric titrations with strong base;
I. The ionic product of water-l^. Mar. Chem. 7:89-99.
Gameson, A.L.M., and D.J. Gould. 1975. Effects of solar radiation on the
mortality of some terrestrial bacteria in seawater. pp. 209-219. In:
Discharge of Sewage from Sea Outfalls. Proc. of an International Symposium
held at Church House, London, 27 August to 2 September 1984. A.L.M. Gameson
(ed). Pergamon Press, Oxford, UK.
Grace, R. 1978. Marine outfall systems planning, design, and construction.
Prentice-Hall, Inc., Englewood Cliffs, NJ. 600 pp.
Graham, J.J. 1966. Secchi disc observations and extinction coefficients in
the central and eastern North Pacific Ocean. Limnol. Oceanogr. 2:184-190.
Green, E.J., and D.E. Carritt. 1967. New tables for oxygen saturation of
seawater. J. Mar. Res. 25:140-147.
Hanes, N.B., and R. Fragala. 1967. Effect of seawater concentration on
survival of indicator bacteria. J. Water Pollut. Control Fed. 39:97-104.
Hendricks, T.J. 1987. Development of methods for estimating the changes in
marine sediments as a result of the discharge of sewered municipal waste-
waters through submarine outfalls. Part I - sedimentation flux estimation.
Final Report. Prepared for U.S. Environmental Protection Agency, Environmen-
tal Research Laboratory, Newport, OR. Southern California Coastal Water
Research Project Authority, Long Beach, CA. 65 pp.
B-68
-------
Herring, J.R., and A.L. Abati. 1978. Effluent particle dispersion.
pp. 113-125. In: Coastal Water Research Project Annual Report. 'Southern
California Coastal Water Research Project, El Segundo, CA.
Hyer, P.V., C.S. Fang, E.P. Ruzecki, and W.J. Hargis. 1971. Hydrography
and hydrodynamics of Virginia estuaries. II. Studies of the distribution
of salinity and dissolved oxygen in the upper York system. Virginia
Institute of Marine Science, Gloucester Point, VA. 167 pp.
Kelts, K., and K.J. Hsu. 1978. p. 295+. In: Lakes: Chemistry, Geology,
Physics. Lerman, A. (ed). Springer, New York, NY.
Myers, E.P. 1974. The concentration and isotrophic composition of carbon
in marine sediments affected by a sewage discharge. Ph.D. thesis.
California Institute of Technology, Pasadena, CA. 179 pp.
Stumm, W., and J.J. Morgan. 1981. Aquatic chemistry. John Wiley and Sons,
Inc., New York. 780 pp.
Tetra Tech. 1982. Revised Section 301(h) technical support document.
EPA-430/9-82-011. U.S. Environmental Protection Agency, Washington, DC.
Tetra Tech. 1987. A simplified deposition calculation (DECAL) for organic
accumulation near marine outfalls. Final Report. Prepared for U.S. Environ-
mental Protection Agency, Office of Marine and Estuarine Protection,
Washington, DC. Tetra Tech, Inc., Bellevue, WA. 49 pp. + appendices.
Wallace, J.M., and P.V. Hobbs. 1977. Atmospheric science: an introductory
survey. Academic Press, New York NY. 467 pp.
B-69
-------
APPENDIX C
BIOLOGICAL ASSESSMENT
-------
APPENDIX C
BIOLOGICAL ASSESSMENT
Because benthic infauna are sedentary and must adapt to pollutant
stresses or perish, this assemblage is often used to define the spatial
extent and magnitude of biological impacts in the vicinity of sewage dis-
charges. The general changes in benthic community structure and function
that occur under conditions of organic enrichment of the sediments (e.g.,
due to municipal sewage effluent) have been well documented (Pearson and
Rosenberg 1978). Slight to moderate enrichment results in slight increases
in numbers of species, abundances, and biomass of benthic communities (see
Figure 3 in main text), while species composition remains unchanged. As
enrichment increases, numbers of species decline because less tolerant
species are eliminated. The total abundance of organisms increases as a few
species adapted to disturbed environments or organically enriched sediments
become very abundant. When enrichment levels are optimal for those few
species, they become extremely abundant and overwhelmingly dominate the
benthic community (corresponding to the "peak of opportunists" shown in
Figure 3). Biomass generally decreases, however, because many of those
opportunistic species are small. Further organic enrichment of the
sediments drastically reduces the number of species and abundances of
benthic organisms, as conditions become intolerable for most taxa.
Because the model developed by Pearson and Rosenberg (1978) has been
shown to be valid in many benthic environments, it is often instructive to
examine the abundances of species that the authors identify as opportunistic
or pollution-tolerant. Those data, in conjunction with the applicant's data
on numbers of species, total abundances, and biomass at stations in the
vicinity of the outfall, are often sufficient to determine the relative
degree of impact within and beyond the ZID.
C-l
-------
Comparable models that describe changes in the structure and function
of plankton and demersal fish communities in organically enriched receiving
environments have not yet been developed. However, it may be instructive to
examine the scientific literature that is available for the biogeographic
region in which the outfall is located. That literature often contains
information describing the responses of the local fauna and flora to organic
materials and other pollutants, and identifying opportunistic and pollution-
tolerant species. Such information is extremely useful for interpreting
data collected in the vicinity of the outfall.
A variety of analytical tools may be used to conduct biological
comparisons for Section 301(h) applications. Applicants may analyze the
data graphically or statistically, or may use other mathematical tools such
as multivariate analyses (e.g., classification and ordination procedures).
Graphical analyses can be especially useful for presenting data in an easily
understood format. In Figure C-l, data on numbers of species in each
replicate sample at stations in the vicinity of an outfall have been plotted
to show the range of reference values in comparison with values at within-
ZID, ZID-boundary, nearfield, and farfield stations. These data may be
tested statistically to determine those test stations at which mean values
differ from mean values at either or both reference stations. But even
without such tests, the data in Figure C-l clearly indicate that a gradient
of effects occurs near the outfall. Relative to reference conditions,
numbers of species are depressed at the within-ZID and downcurrent ZID-
boundary stations, and may be depressed at the nearfield and upcurrent ZID-
boundary stations.
Graphical analyses are especially useful for presenting data on the
physical characteristics of the habitat. For example, it is often in-
structive to plot water column or substrate characteristics in relation to
distance from the outfall (see Figures C-2 and C-3). Gradients of effects
(as in Figure C-3) are often revealed in such simple presentations. An
especially useful method for presenting data on sediment grain size
distributions that has proven useful in analyses of 301 (h) data was
developed by Shepard (1954). Sediments are classified by the proportions of
C-2
-------
50-1
O
I
CO
UJ
o
o.
UJ
cc
DC
UJ
0.
CO
UJ
o
UJ
D.
(0
U.
O
DC
UJ
ffi
2
40-
30-
20-
10-
•
:
RANGE OF
- REFERENCE
CONDITIONS
•
•
•
NET
CURRENT_
DIRECTION
REFERENCE REFERENCE ZID- WITHIN
1 2 BOUNDARY 1 ZIO
T
ZID
BOUNDARY2
NEARFIELO
FARFIELO
STATION
Figure C-1. Numbers of species collected in replicate benthic grab samples at stations in the
vicinity of the outfall.
-------
o
I
34-|
33-
Q.
O.
Z
IJ
<
(0
32-
31-
30
REFERENCE REFERENCE ZID- WITHIN- ZID
1 2 BOUNDARY I ZID BOUNDARY 2
NEARFIELD FARFIELO
STATION
Figure C-2. Salinity at stations in the vicinity of the outfall.
-------
I
en
o
ffi
DC
<
uj
<
O
i.o-
0.0
REFERENCE REFERENCE ZIO- WITHIN- 2ID-
1 2 BOUNDARY 1 ZIO BOUNDARY 2
NEARFIELD FARFIELO
STATION
Figure C-3. Total organic carbon content of the sediments at stations in the vicinity of the
outfall.
-------
their three major grain-size categories (Figure C-4)
. Sand, silt, and clay are often the most useful categories. However, the
gravel, sand, and mud (silt plus clay) categories are useful where sediments
are relatively coarse. [See Shepard (1963) for information on sediment
grain size scales.]
Statistical tests are among the most effective tools for comparing
biological communities among stations. A variety of statistical tests are
available, the most widely used of which is one way analysis of variance
(ANOVA). ANOVA and other statistical tests have been used extensively for
biological comparisons in the 301(h) program, but they have often been used
improperly. For this reason, procedures for conducting statistical com-
parisons using biological data are discussed briefly below. Applicants are
encouraged to consult references on biostatistics (e.g., Zar 1974; Sokal and
Rohlf 1981) for more specific guidance on the application of these pro-
cedures .
The use of one way ANOVA for biological comparisons is preferred
because ANOVA is an efficient and robust test. ANOVA compares the mean
values of a given variable among stations (or groups of stations) for the
purpose of detecting significant differences at a predetermined probability
level. ANOVA requires a minimum of three replicate values at each station
to estimate the mean value and associated variance.
ANOVA is a parametric test based on three assumptions: the error of an
estimate is a random normal variate, the data are normally distributed, and
the data exhibit homogeneous variances. Corrections for the first are not
easily achieved, and an erroneous assumption can greatly affect the results
of the test. Fortunately, error estimates in survey data are usually
independent.
ANOVA is relatively robust with respect to the assumption that the data
are normally distributed. Substantial departures from normality can occur
before the value of the F-statistic is affected greatly (Green 1979). For
C-6
-------
SAND
NEARFIELD
REFERENCE 2
ZID-BOUNDARY 1
REFERENCE 1
FARFIELD
WITHIN-ZID
ZID-BOUNDARY 2
SILT
CLAY
Figure C-4. Sediment grain size characteristics at stations in the
vicinity of the outfall.
C-7
-------
this reason, tests for normality are not usually conducted before data are
analyzed using ANOVA.
The third assumption, that variances are homogeneous, is critical to
execution of ANOVA. Heterogeneous variances can greatly affect the value of
the F-statistic, especially in cases where the statistical design is
unbalanced (i.e., where numbers of replicate values vary among the stations
or station groups being tested).
Several tests are available to determine whether variances are homo-
geneous. The Fmax test (see Zar 1974; Sokal and Rohlf 1981) and Cochran's C
test (Winer 1971) are both appropriate, although the latter is preferred
because it uses more of the information in the data set. Bartlett's test is
not recommended because it is overly sensitive to departures from normality
(Sokal and Rohlf 1981).
When sample variances are found to differ significantly (P<0.01), a
transformation should be applied to the data. [A more conservative pro-
bability level (e.g., P<0.05) should be used when the statistical design is
unbalanced. ANOVA is sensitive to unbalanced statistical designs.] Sokal
and Rohlf (1981) describe several transformations that may be used. Because
ANOVA on transformed data is usually a more efficient test for detecting
departures from the null hypothesis than is the Kruskal-Wallis test (the
nonparametric analog of ANOVA), the Kruskal-Wallis test should only be used
when the appropriate transformation fails to correct for heterogeneous
variances (Sokal and Rohlf 1981). The Kruskal-Wallis test requires a minimum
of five replicate values per station because it is a test of ranks.
When ANOVA or a Kruskal-Wallis tests are performed, significant
differences (P<0.05) among individual stations or groups of stations may be
determined using the appropriate a posteriori comparison. Of most im-
portance in 301(h) demonstrations are differences among reference stations
and stations within the ZID, at the ZID boundary, and beyond the ZID. It is
primarily these comparisons upon which determination of the presence or
absence of a balanced indigenous population is based.
C-8
-------
Classification analyses (e.g., cluster analyses) have also been used
extensively in the 301(h) program. In the normal classification mode,
stations are grouped by the attributes of the assemblages that occur there
(e.g., species composition and abundance). This type of analysis is very
useful for identifying the stations that are the most similar and least
similar to one another in fauna and/or flora. Because biological communities
respond to organic materials and other pollutants, stations at which
pollutant impacts are occurring typically cluster together in interpretable
groups. Inverse classification analysis, in which taxa are grouped by the
stations at which they co-occur, is also helpful because it defines
assemblages that are characteristic of different levels and types of
pollutant impacts.
Classification analysis involves two analytical steps: calculation of
a matrix of similarity values for all possible station pairs, and grouping of
stations based on those between-station similarity values. Many similarity
indices and clustering strategies are available to perform these two tasks
(see Boesch 1977; Green 1979; Gauch 1982; Pielou 1984; Romesburg 1984).
However, only the Bray-Curtis similarity index and either the group average
clustering strategy (i.e., the unweighted pair-group method using arithmetic
averages) or the flexible sorting strategy have been used commonly in 301(h)
demonstrations. Their continued use is recommended. The Bray-Curtis index
is easily understood, and has been used widely in ecological studies.
Moreover, two comparisons of similarity indices (i.e., Bloom 1981; Hruby
1987) have shown it to be superior to many of the other commonly used
resemblance measures. Both the group average clustering strategy and the
flexible sorting strategy are recommended because they produce little
distortion of the original similarity matrix. [See Tetra Tech (1985) for
additional rationale on the use of these three indices.]
C-9
-------
REFERENCES
Bloom, S.A. 1981. Similarity indices in community studies: potential
pitfalls. Mar. Ecol. Prog. Ser. 5:125-128.
Boesch, D.F. 1977. Application of numerical classification in ecological
investigations of water pollution. EPA-600/3-77-033. U.S. Environmental
Protection Agency, Corvallis, OR. 115 pp.
Gauch, H.G. 1982. Multivariate analysis in community ecology. Cambridge
Studies in Ecology: 1. Cambridge University Press, Cambridge, UK. 298 pp.
Green, R.H. 1979. Sampling design and statistical methods for environmental
biologists. John Wiley & Sons, Inc., New York, NY. 257 pp.
Hruby, T. 1987. Using similarity measures in benthic impact assessments.
Environmental Monitoring and Assessment 8:163-180.
Pearson, T.H., and R. Rosenberg. 1978. Macrobenthic succession in relation
to organic enrichment and pollution of the marine environment. Oceanogr.
Mar. Biol. Annu. Rev. 16:229-311.
Pielou, E.C. 1984. The interpretation of ecological data - a primer on
classification and ordination. John Wiley & Sons, New York, NY. 263 pp.
Romesburg, H.C. 1984. Cluster analysis for researchers. Lifetime Learning
Publications, Belmont, CA. 334 pp.
Sokal, R.R., and F.J. Rohlf. 1981. Biometry. 2nd ed. W.H. Freeman & Co.,
San Francisco, CA. 859 pp.
Tetra Tech. 1985. Summary of U.S. EPA-approved methods, standard methods,
and other guidance for 301(h) monitoring variables. Final report prepared
for Marine Operations Division, Office of Marine and Estuarine Protection,
U.S. Environmental Protection Agency. EPA Contract No. 68-01-6938. Tetra
Tech, Inc., Bellevue, WA. 16 pp.
Winer, B.J. 1971. Statistical principles in experimental design. 2nd ed.
McGraw-Hill Book Co., New York, NY. 907 pp.
Zar, J.H. 1974. Biostatistical analysis. Prentice-Hall, Inc., Englewood
Cliffs, NJ. 620 pp.
C-10
-------
APPENDIX D
NAVIGATIONAL REQUIREMENTS AND METHODS
-------
CONTENTS
Paoe
LIST OF FIGURES iii
LIST OF TABLES iv
MONITORING STATION LOCATIONS D-l
ACCURACY LIMITATIONS D-l
POSITIONING ERROR D-4
SUMMARY OF RECOMMENDED PROCEDURES AND EQUIPMENT D-7
CANDIDATE SYSTEM SELECTION D-7
SHALLOW-WATER POSITIONING METHODS D-ll
USE OF LORAN-C D-13
SYSTEM SELECTION PROCEDURE " D-14
REFERENCES D-18
-------
FIGURES
Number Page
D-l Examples of some key 301(h) monitoring station locations for
a medium-large marine municipal discharge 0-2
D-2 Locations of ZID-boundary stations for selected ZID sizes 0-6
D-3 Examples of differential Loran-C error ellipse orientation
at a ZID-boundary sampling station 0-15
0-4 Navigation system preliminary screening criteria 0-17
-------
TABLES
Number Page
D-l Example ZID-boundary station locations 0-5
D-2 Summary of recommended systems D-9
D-3 Theoretical error ellipses of differential Loran-C for
various U.S. locations D-16
IV
-------
APPENDIX 0
NAVIGATIONAL REQUIREMENTS AND METHODS
Information presented below addresses navigational requirements and
methods for Section 301(h) dischargers. It is summarizes more detailed
discussions in Tetra Tech (1987, 1988).
MONITORING STATION LOCATIONS
Compliance with conditions of a secondary treatment variance
requires monitoring at a site-specific array of sampling locations. The
types of stations usually specified in 301(h) monitoring programs are
depicted in Figure D-l. Positioning accuracy is most critical for the
within-ZID and ZID-boundary stations (Stations ZQ, I\, l^ in Figure D-l).
Applicants must be able to sample at a specific boundary location on any
given occasion, and to return to nearly the same location on subsequent
trips. At gradient (Gj, 63, 63, 64) and control or reference (Cj) stations,
initial accurate location is not as critical. However, it is important to
relocate these stations accurately during subsequent surveys to enable
quantification of temporal changes in the variables sampled (e.g., benthic
community characteristics). This requirement for high repeatable accuracy
also applies to stations in or near special habitats (Hj, H2). The ability
to conduct sampling at the appropriate depth contour is also very important.
Sampling programs for 301(h) typically include requirements that a bottom
sampling station can be relocated to within 10 m (32.8 ft).
ACCURACY LIMITATIONS
Both the procedures and equipment used to establish a navigational
position contribute errors that affect the overall accuracy of a fix.
Absolute or predictable accuracy is a measure of nearness to which a system
can define a position by latitude and longitude (Bowditch 1984). Repeatable
D-l
-------
ro
COASTAL
TREATMENT
FACILITY
ZID BOUNDARY -
,-z.
^
X '
Za
i
z,
x ••
G,
•60m X
G
IX
Ga
PREDOMINANT
KEY.
G
H
R
S
1
Z
GRADIENT
HABITAT
REFERENCE
NEARSHORE
TRAWL
ZONE OF INITIAL DILUTION
^^
CURRENT
1 ? 1
TJ gom 1
Figure D-1. Examples of some key 301 (h) monitoring station locations for a medium-large
marine municipal discharge.
-------
or relative accuracy is a measure of a system's ability to return the user
to a given position with coordinates that were previously measured with the
same system. The difference between these two accuracies can be substantial.
For example, depending on one's location in the coverage area, Loran-C has a
repeatable accuracy in offshore areas of 15-90 m (49-295 ft), but an absolute
accuracy of 185-463 m (607-1,519 ft) (Dungan 1979). In many instances,
repeatable accuracy is more important than absolute accuracy (e.g.,
retrieval of crab pots, return to desirable fishing grounds, avoidance of
underwater obstructions, and reoccupation of reference stations).
For coastal outfall monitoring, both repeatable and absolute accuracy
can be important, depending on the type of sampling site. For within-ZID
and ZID-boundary stations, both accuracies are important because sampling
stations must be located within or very near the boundary and be repeatedly
occupied during the program. For gradient, special habitat, and reference
stations, repeatable accuracy is more important than absolute geographic
location. Once such a station is established within a special habitat, it
is often necessary to return to the same site to identify temporal variations
in the previously sampled biological community. Thus, it is important to
select navigational procedures and equipment with both the absolute and
repeatable accuracies needed to meet the monitoring program objectives.
Because repeatable accuracy of navigational equipment is usually at
least 1 order of magnitude better than absolute accuracy, the latter
frequently limits the overall positioning accuracy of a sampling vessel
during coastal monitoring programs. Therefore, the following discussion
focuses on absolute accuracies that can be achieved by various procedures
and associated equipment.
Practical considerations also limit the accuracy of an offshore
positional fix. Resolution of a position to better than 1-2 m (3.3-6.6 ft)
becomes meaningless when measuring the location of a moving vessel (e.g.,
during trawling) or a vessel that is on station but pitching and rolling.
D-3
-------
Antenna movement alone usually precludes higher resolution in position
coordinates. Exceptions to this rule can occur when conditions are
unusually calm.
POSITIONING ERROR
Many factors contribute to the total error in position of the water
column or benthic sampling point. These factors include movement or drift
of the "on-station" vessel, offsets between the deployment point of sampling
equipment and the navigational system antenna, and offsets between the
deployment point and the subsurface location of the sampling or profiling
equipment, and error in the ship's initial location. Most of these factors
are site- or operationally specific, and can be estimated with varying
degrees of confidence. Because the accuracy to which the actual sampling
point is known is highly dependent on all these factors, they should be
carefully considered in both the design and conduct of monitoring programs.
A ZID-boundary error proportional to some percentage of the ZID
dimension has been selected as the controlling parameter for 301(h)
navigational requirements. Because ZID size is proportional to water depth,
the allowable error in position is thus also proportional to depth. For
example, ZID-boundary stations can be located at a distance from the
diffuser axis equal to one-half the ZID width plus 20 percent of the water
depth at mean tide level. The allowable maximum error in the location of
these stations can then be ±20 percent of the water depth. As a result, the
closest to the diffuser that sampling would occur is at the ZID boundary,
and the farthest from the diffuser that sampling would occur is 40 percent
of the water depth beyond this boundary. Nominally, however, sampling would
be performed within a distance from the ZID boundary equal to 20 percent of
the water depth. Example ZID-boundary station locations using this approach
for a variety of ZID sizes are listed in Table D-l. The ZID-boundary and
sampling station locations for discharges at the 100-, 60-, and 20-m (328-,
197-, and 66-ft) depths are shown in Figure D-2.
D-4
-------
TABLE D-l. EXAMPLE ZID-BOUNDARY STATION LOCATIONS
Average
Diffuser
Depth
(•)
100
90
80
70
60
50
40
30
20
15
10
5
3
Average
Diffuser
Diameter
(•)
4.0
3.6
3.4
3.2
3.0
2.5
2.2
2.0
1.8
1.5
1.5
1.0
0.5
ZID
Width
(•)
204.0
183.6
163.4
143.2
123.0
102.5
82.2
62.0
41.8
31.5
21.5
11.0
6.5
Recommended
Station
Location3
(•)
122.0
109.8
87.7
85.6
73.5
61.3
49.1
37.0
24.9
18.8
13.8
8.5
6.3
Recommended
Allowable
Error6
(•)
±20
±18
±16
±14
±12
±10
±8
±6
±4
±3
±3
±3
±3
a Distance from the zone of initial dilution centerline to the station,
based on 0.5 times the ZID width plus 20 percent of the average water depth
of the diffuser when over 15 m (49 ft).
b Error magnitude is equal to ±20 percent of the average diffuser depth,
when over 15 m (49 ft).
D-5
-------
ZID BOUNDARY
STATION
LOCATION
100 m DEPTH
4.0 m DIFFUSER
ERROR
LIMIT
40m
ZID,
BOUNDARY
-204m-
122m
' OUTFALL PIPE
DIFFUSER
60m DEPTH
3.0 m DIFFUSER"
-a-»
123m
?as m
20 m DEPTH .
1.8 m DIFFUSER
;
1
1
8 m^^»J
1
1
e—
»
41.
249
«•
I
^^m
m
m
!
t
1
1
J
*l
1
1
1
t
Figure D-2. Locations of ZID-boundary stations for selected ZID sizes.
D-6
-------
When discharge depths are less than approximately 15 m (49 ft), the 20
percent error allowance results in an overly restrictive positional error
[i.e., less than ±3 m (9.8 ft)]. Therefore, a positioning error of ±3 m
(9.8 ft) is considered to be more appropriate when sampling station depths
are less than 15 m (49 ft). Although the percent error as a function of
water depth increases at shallower depths, this minimum error is considered
reasonable given available navigating techniques for small sampling vessels
in other than extremely calm waters. Stations beyond the ZID may be
similarly located using the 20 percent of depth rule beyond the 15-m (49-ft)
contour and the +3-m (9.8 ft) error limitation for shallower locations. As
indicated earlier, it is recognized that the ability to reoccupy a given
site can be as important as knowing its exact geographical location.
However, relocation beyond the ZID probably will not be a problem if the same
navigational equipment used to locate ZID-boundary stations is also used
elsewhere.
SUMMARY OF RECOMMENDED PROCEDURES AND EQUIPMENT
Based on Tetra Tech's evaluation of optional positioning methods, the
systems recommended for coastal positioning include theodolites, sextants,
electronic distance measuring instruments (EDMIs), total stations, and
microwave and range-azimuth systems. Although satellite systems offer
adequate accuracy (when used in a differential mode), their use may be
limited because a sufficient number of satellites may not always be
available.
CANDIDATE SYSTEM SELECTION
The details of positioning techniques and associated equipment are
described in Tetra Tech (1987). No single system is best for all coastal
monitoring purposes. Needs vary according to the size and complexity of the
planned monitoring program, the nature of the immediate and surrounding
areas, and other navigational or surveying requirements of a municipality.
D-7
-------
Positioning techniques fall into three principal measurement categories:
• Multiple horizontal angles
Theodolite intersection
Sextant angle resection
• Multiple electronic ranges
Distance-measuring instruments
Range-range mode
Hyperbolic mode
Satellite ranging
• Range and angle
Theodolite and EDMI
Total station
Range-azimuth navigation systems
Systems within these categories that will meet or exceed the positional
accuracy recommended herein are summarized in Table D-2. Additional
information on the recommended categories is provided below.
Multiple Horizontal Angles
In the multiple horizontal angles category, theodolites were found to
have the angular accuracies required for the maximum ranges anticipated.
Their costs range from $1,000 to $4,000 (30-sec vs. 10-sec accuracy), and
D-8
-------
TABLE D-2. SUMMARY OF RECOMMENDED SYSTEMS
Category
Theodolite
Sextant
Representative3
Equipment
Table B-l
Table B-2
Table B-3
Accuracy
10-30 sec
±1 m (3.3 ft)
+10 sec
+2 m (6.6 ft)
Cost Advantages
$1.000- $4. 000 Traditional method.
Inexpensive. High
accuracy. Successfully
applied. Restricted
areas.
$1.000-$2.000 Rapid. Easy to imple-
ment. Most widely used.
Di sadvantages
Line-of -sight. Two
manned shore stations.
Simultaneous measure-
ments. Limits on
intersection angles.
Area coverage; station
movement .
Simultaneous measure-
ment of two angles.
o
I
to
EOMI
Total stations
Table B-4
Table B-5
1.5-3.0 cm
$3.500-$15.000
5-7 cm
$8.000-$30.000
Low cost. No shore party.
High accuracy.
Extremely accurate.
Usable for other surveying
projects. Cost. Compact,
portable, rugged.
Single onshore station.
Other uses. Minimum
logistics.
Target visibilities,
location, maintenance.
Line-of-sight. Best
in calm conditions.
Limits on acceptable
angles.
Motion and direction-
ality of reflectors.
Visibility, unless
microwave. Two shore
stations. Ground wave
reflection.
Reflector movement and
directionality. Prism
costs.
Microwave
navigation
systems
Range-azimuth
systems
Satellite systems
Table B-6 ±1-3 m $40.000-$90.000
Table B-10 0.01° and 0.5 m $65. 000-$ 100. 000
Table B-9 1-10 m $150. 000- $300. 000
(initial units)
No visibility restric-
tions. Multiple users.
Highly accurate. Radio
llne-of -sight.
High accuracy. Single
station. Circular cover-
age.
High accuracy. Minimum
logistics. Use in re-
stricted/congested areas.
Future cost. No shore
stations.
Cost. Multiple onshore
stations. Logistics.
Security.
Single user. Cost.
Current coverage. Ini-
tial development cost.
a Table references refer to Tetra Tech (1987).
-------
they are readily available because they are widely used as a surveying
instrument. At least two theodolites, two operators, a vessel siting
target, and a three-way communications link to coordinate fixes are
required. Visibility can be a limiting factor.
By comparison, sextant angle resection can be performed using one
instrument if the vessel is stationary, or using two instruments simul-
taneously if the vessel is moving. Achievable angular accuracy of ±10 sec
is adequate, and relatively inexpensive sextants ($1,000-$2,000) are readily
available. Again, visible range can be limiting. Shooting an accurate fix
from a non-stationary platform in any significant sea or swell could be more
difficult than shooting with theodolites from shore. A distinct advantage
of sextant angle resection is location of the navigators on the survey
vessel. The method generally requires highly visible shore targets and a
three-arm protractor for plotting positions.
Multiple Electronic Ranges
Positioning using multiple ranges can be accomplished with two staffed
EDMI stations. Accuracies were found to be more than adequate but ranges
were found to be marginal [if needed beyond 3 km (1.9 mi)] unless multiple
prisms are used. Because such prisms are directional, procurement of
multiple clusters for more than one direction could result in substantial
additional costs. The initial investment (i.e., without multiple prisms) is
$3,500-$5,000 each for two shorter-range units, or $8,000-$15,000 each for
two longer-range units. Several microwave navigation systems with more than
adequate range and sufficient accuracy are available in the $40,000-$90,000
range. Limitations include geometry of shore stations; position of the
vessel in the coverage area (i.e., crossing angle limitations); and possible
interferences due to line-of-sight obstructions, sea-surface reflective
nulls, and land-sea boundaries. The hyperbolic mode provides multiple user
capability, but at the cost of an additional shore station.
Satellite ranging holds promise because required accuracies should be
achievable in the near future. Transit satellite-based systems do not offer
D-10
-------
sufficient accuracy, except with multiple passes, and multiple passes are
impractical when a given sampling station is occupied only briefly.
Accuracies needed will undoubtedly be achievable in the future using
differential global positioning system (GPS) techniques ($10,000-$40,000 for
first units; as low as $1,000 for subsequent production models). Commercial
geosynchronous satellite networks, such as GEOSTAR, may become available at
a proposed system interrogator cost of $450 plus a monthly fee. However,
this system is in the very early stages of planning, having only recently
received FCC approval of requested frequencies. Finally, the codeless GPS
systems (SERIES or Aero Services Marine GPS System) currently under
development could be used, but at a current cost of over $250,000.
Range and Angle
Systems in the range-azimuth category show great promise. Required
angular and range accuracies are available, only one shore station is
needed, and costs depend on system refinements. At the low end of the
scale, an EDMI and theodolite could be paired with a communication link for
approximately $10,000-$12,000. Total stations developed specifically for
this requirement range in cost from $8,000 for a manual station to $15,000-
$30,000 for a fully automatic station. Optical and infrared range limita-
tions apply to these systems. The three range-azimuth navigational systems
examined provide sufficient positional accuracy with a single station at
costs ranging from $65,000 for manual tracking to $70,000-$100,000 for fully
automatic tracking.
SHALLOW-WATER POSITIONING METHODS
When sampling stations are located in relatively shallow water, they
can be identified by relatively inexpensive methods (in addition to those
discussed earlier in this report). Provided the center of the ZID over the
outfall can be located (e.g., by diver-positioned surface float), an optical
range finder may be used to establish the required distances to nearby water
quality or biological sampling stations. An optical range finder is used by
simply focusing a split-image on the target float, enabling the slant
D-ll
-------
distances to the target to be read from the instrument scale. When combined
with a careful compass reading, this distance reading allows positioning of
the sampling vessel.
A survey of accuracies claimed for commercially available instruments
suggests that the ±3 m (9.8 ft) recommended minimum accuracy can be achieved
for ranges up to approximately 100 m (328 ft) from the surface target. The
Lietz Model 1200, for example, provides an accuracy of ±1 m (3.3 ft) at
100 m (328 ft). Beyond this distance, instrumental errors increase rapidly.
For the instrument cited, a ±9 m (29.5 ft) accuracy is quoted at 300 m (984
ft). The suggested U.S. list prices of optical range finders vary from $35
to $120 (Folk, L., 21 March 1985, personal communication).
An acceptable alternative method for collecting bottom samples from
desired locations in shallow water is to use divers. Provided visibility is
adequate, divers may measure radial distances to desired locations by
holding a tape at the outfall and traversing the appropriate distance over
the bottom in the proper direction.
Visual ranges have sometimes been used to establish a station position.
This method requires that a minimum of two objects are in alignment,
enabling the vessel to be placed on a common axis extending to the vessel's
position. Simultaneous siting on a second set of at least two objects
places the vessel at the intersection of the two common axes. The accuracy
of each visual range is highly dependent on the quality of the visual range
(e.g., alignment), the distance from the alignment objects to the vessel,
and the angle between each range. Also, the number of visual ranges used
affects the magnitude of the positional error. Although this technique is
frequently used for positioning single sampling stations in bays, harbors,
and other areas in which two or more conveniently alignable targets can be
selected, the method is not considered acceptable for coastal monitoring at
ZID-boundary stations. Also, it is not likely that a sufficient number of
alignment target-pairs will be present for all desired locations. In
addition, the unpredictability of repeatable position error detracts from
the value of this method.
D-12
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Permanent installation of a marker buoy at the outfall terminus or
midpoint of the diffuser allows easy return to this point on subsequent
sampling trips. Using the previously discussed range-finder technique or a
line of desired length enables positioning at desired distances from the
marker buoy. However, it is not uncommon to lose such a buoy due to
vandalism, impact, or severe weather conditions. Therefore, it is necessary
that the sampling party be prepared to relocate the outfall (e.g., by diver,
sonar, or pinger mounted on the outfall itself), if location of stations is
dependent on knowledge of the outfall location.
Because the techniques described here are inexpensive to implement (as
are use of the sextant resection or theodolite intersection methods), they
are attractive to small coastal municipalities. However, use of more
sophisticated and less labor-dependent techniques may be achievable at
moderate costs by renting or leasing, rather than buying such equipment.
USE OF LORAN-C
In their evaluation of positioning methods, Tetra Tech (1987) concluded
that Loran-C did not provide the absolute and repeatable accuracies needed
for the 301(h) program. However, because Loran-C is in such wide use and is
relatively inexpensive, use of Loran-C in a special operating mode was re-
examined in Tetra Tech (1988). The special operating mode is called
differential Loran-C, which requires an additional Loran-C receiver onshore
at a known geographic location. At this location, the Loran-C signals are
received, and a correction is generated and transmitted to the survey
vessel, allowing the correction to be applied to signals received by the
ship's Loran-C unit.
Differential Loran-C was found to significantly improve the positional
accuracies achievable compareu to Loran-C in the normal mode. During a
simulated monitoring program near Newport Beach, California, normal Loran-C
positional errors of 40-50 m (131-164 ft) were reduced to 7-15 m (23-49 ft)
using differential Loran-C in conjunction with special vessel operating
D-13
-------
procedures, a video display, and data averaging techniques. Higher
accuracies are expected in other coastal areas where improved lattice line
crossing angles occur. Acceptability may depend on relative orientations of
the diffuser and the error ellipse axes (Figure D-3, Table D-3). For those
considering use of differential Loran-C, a procedure for determining the
error in a ZID-boundary station location is provided in Tetra Tech (1988).
SYSTEM SELECTION PROCEDURE
A procedure for selecting an appropriate navigation system is described
in detail in Tetra Tech (1987). The procedure involves definition of
positioning requirements, establishment of screening criteria (e.g., range,
accuracy, availability, and costs), review of candidate systems, and
evaluation of purchase/lease options. As indicated in Figure D-4, a
stepwise screening technique is recommended to identify an optimal system
for a given monitoring program. At each step in the screening process,
systems that cannot achieve the required criterion are removed from further
consideration.
D-14
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OUTFALL PIPE
ZID
BOUNDARY
ELLIPSE ROUGHLY
PARALLEL TO DIFFUSER
95% PROBABILITY
ELLIPSE
X.Y)
- ACROSS-ZID
ERROR VARIATION
ACROSS ZID
ERROR VARIATION
ELLIPSE ROUGHLY
PERPENDICULAR TO
DIFFUSER
X.Y Coordinates of ZID-
Boundary Sampling
Station.
gJH 95% Probability of
Actual Sampling
Station Position being
in this Area.
Figure D-3. Examples of differential Loran-C error ellipse orientation
at a ZID-boundary sampling station.
D-15
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TABLE D-3. THEORETICAL ERROR ELLIPSES OF DIFFERENTIAL LORAN-C
FOR VARIOUS U.S. LOCATIONS
Location
Anchorage, AK
Puget Sound, WA
San Francisco, CA
Los Angeles, CA
San Diego, CA
Mississippi Delta, LA
Panama City, FL
Chesapeake Bay, VA
Boston, MA
Approximate
Direction
of
Major Axis
NW/SE
NW/SE
NE/SW
NE/SW
N/S
NW/SE
N/S
W/E
N/S
Length
of
Major Axis3
70
180
60
90
90
50
30
40
30
Length
of
Minor Axis3
20
40
30
30
20
20
20
20
20
3 Lengths are given to the nearest 10 m based on 95 percent confidence level
error ellipses. Standard deviation of time differences is 25 nsecs
(achievable with differential Loran-C).
D-16
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CANDIDATE SYSfEV
Figure D-4. Navigation system preliminary screening criteria.
D-17
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REFERENCES
Bowditch, N. 1984. American practical navigator. An epitome of navigation.
Defense Mapping Agency Hydrographic/Topographic Center, Washington, DC. pp.
1272, 1278.
Dungan, R.G. 1979. How to get the most our of LORAN-C. SG 54. Extension
marine advisory Program, Oregon State University, Corvallis, OR. 12 pp.
Folk, L. 21 March 1985. Personal Communication (phone by Dr. William P.
Muellenhoff, Tetra Tech). Kuker-Rankin, Inc., Settle, WA.
Tetra Tech. 1987. Evaluation of survey positioning methods for nearshore
and estuarine waters. EPA-430/9-86-003. Final report prepared for Marine
Operations Division, Office of Marine and Estuarine Protection, U.S.
Environmental Protection Agency. Tetra Tech, Inc., Bellevue, WA. 54 pp. +
appendices.
Tetra Tech. 1988. Evaluation of differential Loran-C for positioning in
nearshore marine and estuarine waters. Draft report prepared for Marine
operations Division, Office of Marine and Estuarine Protection, U.S.
Environmental Protection Agency. EPA Contract No. 68-C8-0001. Tetra Tech,
Inc., Bellevue, WA.
D-18
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APPENDIX E
URBAN AREA PRETREATMENT REQUIREMENTS
-------
CONTENTS
Paoe
LIST OF FIGURES iii
LIST OF TABLES iv
INTRODUCTION E-l
APPLICABLE TREATMENT PROGRAM APPROACH E-3
U.S. EPA GUIDANCE E-3
LOCAL LIMITS E-5
SECONDARY REMOVAL EQUIVALENCY APPROACH E-7
SECONDARY TREATMENT PILOT PLANT DESIGN CRITERIA E-10
SECONDARY TREATMENT PILOT PLANT STARTUP E-14
SECONDARY TREATMENT PILOT PLANT OPERATING CRITERIA E-16
TOXIC POLLUTANT MONITORING PROGRAM, TESTING PROCEDURES, AND
QUALITY ASSURANCE/QUALITY CONTROL E-24
SAMPLING FREQUENCY E-25
SAMPLE COLLECTION AND ANALYSIS E-26
QA/QC E-43
UPGRADING TO A FULL-SCALE SECONDARY TREATMENT FACILITY E-50
DEMONSTRATING COMPLIANCE USING PILOT PLANT DATA E-55
REFERENCES E-56
ATTACHMENT 1: U.S. EPA OFFICE OF WATER ENFORCEMENT AND PERMITS
PROCEDURES FOR DEVELOPING TECHNICALLY BASED LOCAL LIMITS E-59
ATTACHMENT 2: U.S. EPA GUIDANCE MANUAL ON THE DEVELOPMENT AND
IMPLEMENTATION OF LOCAL DISCHARGE LIMITATIONS UNDER THE
PRETREATMENT PROGRAM E-68
E-ii
-------
FIGURES
Number Pace
E-l Components of a conventional activated sludge system E-12
E-iii
-------
TABLES
Number . Page
E-l Effluent water quality values that shall not be exceeded
under secondary treatment E-9
E-2 Secondary treatment pilot plant design criteria E-ll
E-3 Conventional activated sludge design parameters E-13
E-4 Pliot plant monitoring schedule E-17
E-5 List of test procedures approved by U.S. EPA for inorganic
compounds in effluent E-28
E-6 List of test procedures approved by U.S. EPA for non-
pesticide organic compounds in effluent E-35
E-7 List of test procedures approved by U.S. EPA for pesticides
in effluent E-38
E-8 Recommended sample sizes, containers, preservation, and
holding times for effluent samples E-41
E-9 Reported values for activated sludge biological process
tolerance limits of organic priority pollutants E-51
E-10 Reported values for activated sludge biological process
tolerance limits of inorganic priority pollutants E-53
E-iv
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INTRODUCTION
Section 303(c) of the Water Quality Act of 1987 amended Section 301(h)
of the 1977 Clean Water Act by adding the "urban area pretreatment require-
ment." This requirement applies only to POTWs serving a population of at
least 50,000 and only to toxic pollutants introduced by industrial dis-
chargers. For each toxic pollutant introduced by an industrial discharger
in affected POTWs, the applicant must demonstrate that it meets one of the
following two conditions:
• Has an "applicable pretreatment requirement in effect"
• Achieves "secondary removal equivalency."
This new statutory requirement complements the toxics control program
requirements in the existing Section 301(h) regulations (40 CFR 125.66) and
other pretreatment requirements in 40 CFR 403.
The intent of this appendix is to help POTWs interpret and comply with
the new requirement. For site-specific reasons, concepts and procedures
recommended herein may not necessarily apply to all 301(h) applicants.
Issues that are not addressed by this appendix should be directed to U.S. EPA
Regional offices. Applicants should also check with appropriate state and
local agencies for any explicit requirements (e.g., water quality standards)
that apply to them. The procedures to demonstrate compliance with this
urban area requirement must be formulated and implemented by each POTW with
concurrence from the appropriate U.S. EPA Regional office. Compliance with
the urban area pretreatment requirement is required before a 301(h) permit
may be issued by U.S. EPA, although tentative approval may be granted on
demonstration of the applicant's good faith effort.
E-l
-------
When a review of the 301(h) application indicates that noncompliance
with pretreatment requirements is substantial and that the applicant is not
taking effective steps to assure compliance, then U.S. EPA may deny the
permit. Factors relevant to such a decision include the number of non-
complying industrial sources, the nature of their toxic pollutant contri-
bution to the POTW, and potential or actual POTW interference of pass-
through.
E-2
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APPLICABLE TREATMENT PROGRAM APPROACH
Applicable pretreatment requirements for each toxic pollutant may take
one of two forms:
• Categorical standards
• Local limits.
Categorical standards are nationally uniform, technology-based pretreatment
limitations developed for specific industrial categories under Section 307
of the Clean Water Act. All categorical industries must comply with
categorical standards, even if they discharge to a POTW without a federally
approved local pretreatment program. By contrast, local limits are
developed by the POTW to prevent interference with the treatment works or
pass-through of toxic pollutants, as required by 40 CFR 403.5(b).
A given industrial discharger may be subject to categorical standards
for some pollutants and local limits for other pollutants, or to both types
of limitations for the same pollutant. In the latter case, the stricter
standard applies. The urban area pretreatment requirement for all toxic
pollutants entering a POTW will probably require a combination of both forms
of pretreatment standards.
U.S. EPA GUIDANCE
The U.S. EPA Office of Water Enforcement and Permits (OWEP) and the
U.S. EPA Office of Water Regulations and Standards (OWRS) have issued the
following guidance manuals tj assist POTWs in implementing pretreatment
regulations and developing technically based local limits:
E-3
-------
• Guidance Manual for POTU Pretreatment Program Development
(U.S. EPA 1983a)
• Procedures Manual for Reviewing a POTW Pretreatment Program
Submission (U.S. EPA 1983b)
• NPDES Compliance Inspection Manual (U.S. EPA 1984)
• Guidance Manual for Implementing Total Toxic Organics (TTO)
Pretreatment Standards (U.S. EPA 1985a)
• Guidance Manual for the Use of Production-Based Pretreatment
Standards and the Combined Uastestream Formula (U.S. EPA
1985b)
• Pretreatment Compliance Monitoring and Enforcement Guidance
(U.S. EPA 1986a)
• Guidance Manual for Preventing Interference at POTMs (U.S. EPA
1987a)
• Guidance for Reporting and Evaluating POTU Noncompliance with
Pretreatment Implementation Requirements (U.S. EPA 1987b)
• Guidance Manual on the Development and Implementation of
Local Discharge Limitations Under the Pretreatment Program
(U.S. EPA 1987c) (enclosed as Attachment 2 to this appendix).
The implementation and enforcement guidelines in these manuals require the
POTW to undertake the following:
• In the POTW industrial waste survey (which must be updated on
a regular basis), identify and locate all industries that
discharge pollutants into the POTW
E-4
-------
• Demonstrate that the.sampling procedures and analysis program
undertaken were adequate to characterize industrial and
nonindustrial pollutant loading to the POTVI, and pollutant
concentrations in the POTW influent, effluent, and sludge
• Compare measured pollutant concentrations to applicable sludge
criteria or guidelines, water quality criteria or standards,
and POTW process inhibition thresholds
• Demonstrate that the existing pretreatment program is
adequate to control industrial user discharges, and that it
contains specific numerical limits for industrial pollutants
• Demonstrate that local limits are technically based, adequate
to protect the POTW, and allow compliance with its NPDES
permit
• Demonstrate that steps have been taken to identify the causes
of past POTW operating problems (e.g., industrial discharges,
equipment failures, plant upsets, NPDES permit violations,
sludge contamination) and correct them
• Demonstrate that POTW inspection and compliance monitoring
procedures exist and are being implemented
• Demonstrate that the needed resources (e.g., funds, staff,
equipment) are available to carry out program requirements.
LOCAL LIMITS
The technical approach used by a POTW to develop local limits is
primarily a local decision, provided that the local limits are enforceable
and scientifically based. Most POTWs use the headworks loading method in
the U.S. EPA (1987c) local limits guidance manual. OWEP-recommended
procedures for developing local limits appear as Attachment 1 to this
E-5
-------
appendix. Best professional judgment can be used to establish pretreatment
requirements when data or criteria are insufficient to perform a pollutant
loading analysis for a specific pollutant of concern. The applicant may
implement the local limits via uniform maximum allowable concentrations or
discharger-specific maximum allowable mass emissions.
Local limits should be reviewed and revised periodically in response to
changes in federal or state regulations, environmental protection criteria,
plant design and operational criteria, or the nature of industrial contri-
butions to POTW influent. For example, the following specific changes
could affect criteria used to derive local limits:
• Changes in NPOES permit limits to include additional or more
restrictive toxic pollutant limits
• Changes in water quality limits including toxicity require-
ments
• Changes in sludge disposal standards or POTW disposal methods
• Availability of additional site-specific data pertaining to
pollutant removal efficiencies and/or process inhibition.
OWEP is presently developing guidance to determine the technical
adequacy of 1ocal limits and to ensure their enforcement. This guidance
will also clarify the use of best professional judgment for establishing
local discharge limits or technology-based limits when the data are
insufficient.
E-6
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SECONDARY REMOVAL EQUIVALENCY APPROACH
One approach that 301(h) applicants may use to satisfy the new urban
area pretreatment requirement is to demonstrate secondary removal equiva-
lency. As noted in 40 CFR 125.65(d):
An applicant shall demonstrate that it achieves secondary removal
equivalency through the use of a secondary treatment pilot plant
at the applicant's facility which provides an empirical determina-
tion of the amount of a toxic pollutant removed by the application
of secondary treatment to the applicant's discharge, where the
applicant's influent has not been pretreated. Alternatively, an
applicant may make this determination using influent that has been
pretreated, notwithstanding section 125.58(w).
In effect, the applicant's existing treatment processes and industrial
pretreatment program must remove at least as much of a toxic pollutant as
would be removed if the applicant applied secondary treatment and did not
have an industrial pretreatment requirement for that pollutant. This
approach can be represented as follows:
POTW existing + industrial = POTW existing + no industrial
treatment pretreatment treatment pretreatment
upgraded to
secondary treatment
U.S. EPA recognizes, however, that it would be simpler for applicants to
perform this demonstration by using a secondary treatment pilot plant on the
actual pretreated influent. This approach is shown below:
POTW existing + industrial = POTW existing +• industrial
treatment pretreatment treatment pretreatment
upgraded to
secondary treatment
E-7
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Although U.S. EPA will consider them, demonstrations to account for the
effects of industrial pretreatment will probably be difficult. The
secondary treatment pilot plant approach is conservative (i.e., protective)
where it uses influent that has received industrial pretreatment, because the
calculated required removals will be greater than those resulting from a
demonstration using influent that has not been pretreated.
Secondary treatment at POTWs typically involves biological processes
that remove organic matter through biochemical oxidation, usually variations
of the activated sludge process. Other physical-chemical secondary treatment
processes (e.g., coagulation, filtration, carbon adsorption) may also be
used, particularly for nonbiodegradable wastewaters. The specific secondary
treatment process used by a POTW is dependent on numerous factors such as
wastewater quantity, waste biodegradability, and available space at the POTW
site. Each POTW must determine the best strategy and the most applicable
treatment process for complying with the secondary removal equivalency
requirements.
The level of effluent quality attainable through the application of
secondary treatment is defined in 40 CFR 133 (Table E-l). Treatment
processes that are considered equivalent to secondary treatment (e.g.,
trickling filter, waste stabilization pond) are discussed in 40 CFR
133.105. Minimum levels of effluent quality attainable from these equivalent
treatment processes differ from those shown in Table E-l.
Because secondary treatment levels were defined only for BOD, suspended
solids, and pH, POTWs were usually not required to institute technology
specifically to control toxic pollutants. Under the 1977 Clean Water Act,
toxic pollutants in the POTW effluents were controlled predominantly through
pretreatment programs, categorical standards, and local POTW limits required
by the issuance of NPDES permits.
E-8
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TABLE E-l. EFFLUENT WATER QUALITY VALUES THAT SHALL NOT
BE EXCEEDED UNDER SECONDARY TREATMENT
Variable3
BOD5
CBOD5b
SS
PH
30-Day
Average
30 mg/L
25 mg/L
30 mg/L
6.0
7-Day 30-Day Average
Average (Percent Removal)
45 mg/L
40 mg/L
45 mg/L
to 9.0
>85
>85
>85
a BODs = 5-day measure of biochemical oxygen demand; CBODs = 5-day measure
of carbonaceous biochemical oxygen demand; SS = suspended solids.
b At the option of the NPDES-permitting authority, CBODs may be substituted
for 8005.
E-9
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SECONDARY TREATMENT PILOT PLANT DESIGN CRITERIA
A secondary treatment pilot plant should be designed for an average
flow of approximately 150 GPD. The flow rate should remain constant over a
24-h period. The pilot plant should .require minimum operation and main-
tenance time, and must be able to operate unattended for 16-24 h. The
organic loading will vary with the diurnal and seasonal fluctuations in the
8005 concentration in the existing POTW effluent. Design criteria for the
secondary treatment pilot plant are shown in Table E-2.
A conventional activated sludge system (Figure E-l) for a POTW includes
the following related components:
• Single or multiple reactor basins (i.e., aeration tanks)
where microorganisms consume the organic wastes. These
basins are designed to allow for complete mixing of its
contents, which are defined as mixed liquor suspended solids
(MLSS). Each basin must provide typical hydraulic retention
times of 2-24 h.
• Pressurized or atmospheric oxygen-containing gases that are
dispersed into the reactor basin.
• Settling basin (i.e., final clarifier) to separate the MLSS
from the treated wastewater.
• Equipment to collect the solids in the settling basin, and
to recycle the active biological solids (i.e., activated
sludge) to the reactor basin.
• Equipment to remove excess active biological solids from the
system.
Typical design variables for the conventional activated sludge process are
shown in Table E-3. Additional information on activated sludge systems is
E-10
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TABLE E-2. SECONDARY TREATMENT PILOT PLANT DESIGN CRITERIA
Reactor Basin (Aeration Tank)
Volume 50 gal (189 L)
Detention time 8 h
Organic loading 25-60 Ib BOD/1,000 ft3/day (0.4-1.0 kg/m3/day)
Air requirement 0.20-0.44 ft3/min (0.33-0.75 m3/h)
Settling Basin (Final Clarifier)
Volume
Surface Area
Overflow Area
Solids Loading
Weir Length
Detention Time
20 gal (76 L)
0.375 ft2 (0.035 m2)
400 gal/ft2/day (16.3 n^/m^day)
14 Ib/ft2/day (68.4 kg/m2/day)
0.5 ft (0.152 m)
3 h
Influent Feed Pump
Capacity
Type
0-290 gal/day (0-12.7 L/sec)
Peristaltic
Return Activated Sludge Pump
Capacity 0-130 gal/day (0-5.7 L/sec)
E-ll
-------
MFLUENT
EFFLUENT
m
i
WASTE
SLUDGE (WAS)
Figure E-1. Components of a conventional activated sludge system.
-------
TABLE E-3. CONVENTIONAL ACTIVATED SLUDGE DESIGN PARAMETERS
Food to microorganism ratio
Mean cell residence time
Aeration detention time
Oxygen requirements
Return activated sludge
flow rate
0.15-0.4 Ib BOD5/lb MLSS/day
5-15 days
4-8 h
0.8-1.1 Ib (kg) 02/lb (kg)
BOD5 removed
30-100 percent influent flow
Mixed liquor suspended solids (MLSS) 1,500-4,000 mg/L
Organic loading at
3,000 mg/L MLSS
Respiration (oxygen uptake) rate
at 3,000 mg/L MLSS
Sludge volume index
Waste activated sludge
20-60 Ib BOD/1,000 ft3
(0.3-1.0 kg BOD/m3)
15-45 mg oxygen/L/h
90-150
0.4-0.6 Ib (kg)/lb (kg)
BOD removed
E-13
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provided by the Water Pollution Control Federation [(WPCF) 1976, 1987] and
WPCF/American Society for Civil Engineers (1977).
SECONDARY TREATMENT PILOT PLANT STARTUP
In the activated sludge process, microorganisms metabolize nearly all
soluble organic matter in the influent. The microorganisms (i.e., active
biological solids) must be removed from the settling basin to produce an
acceptable effluent, and the proper operation of the settling basin is
critical. The following process control parameters should be monitored to
ensure proper operation of the activated sludge system:
• MLSS
• Mixed liquor volatile suspended solids (MLVSS)
• Dissolved oxygen
• Sludge volume index (SVI)
• Sludge density index (SDI)
• Organic loading
• Return activated sludge (RAS) flow rate
• Waste activated sludge (WAS) flow rate
• Mean cell residence time (MCRT)/solids retention time (SRT)
• Food/microorganism ratio (F/M)
• Temperature
E-14
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• Hydrogen ion concentration (pH)
• Respiration rate (RR).
In addition to these process control parameters, microscopic examination of
the MLSS should be performed.
An initial F/M ratio of 0.2 should be achieved. Field operators should
adjust the F/M ratio by changing the MLSS concentration in the reactor
basin if the required 30-day average effluent quality (i.e., 30 mg/L BOD,
30 mg/L suspended solids) cannot be achieved. If temperature varies
substantially between summer and winter, the F/M ratio will probably need to
be lowered during winter to achieve the required effluent quality.
The pilot plant should be seeded with MLSS from a local domestic
wastewater treatment facility. Acclimation of the pilot plant will require
about 4-6 wk. If there is no local source of MLSS, the pilot plant may be
started using the POTW's effluent. An additional 4-6 wk may be needed to
ensure that the MLSS meets the desired design concentration.
The MLSS should be fed with domestic wastewater for the first 2-3 days.
The volumetric proportion of the effluent should then be adjusted to 10
percent of the total feed for 4-5 days. After the initial week of operation,
the volumetric proportion of the regular POTW effluent in the pilot plant
feed can be increased approximately 5 percent per day until the system is
receiving 100 percent POTW effluent.
Sampling for 8005 and suspended solids should be conducted daily during
and after the acclimation period. Sampling for toxic pollutants should not
be started until 2 wk after the pilot plant is receiving 100 percent POTW
effluent.
E-15
-------
SECONDARY TREATMENT PILOT PLANT OPERATING CRITERIA
The process control parameters identified in the preceding section
should be monitored to provide information for process control and to
determine treatment efficiency. A monitoring schedule is shown in Table E-4.
The frequency of sample collection and analysis may vary for each POTW,
however, depending on the size of the POTW, available laboratory facilities,
available staff, and technical skills of personnel. Additional sampling and
analysis may be required for abnormal conditions or during periods of process
upsets. Implementation of the monitoring program, data interpretation, and
pilot plant operation and maintenance is estimated to require about 5 labor
hours per day. Each process control parameter is discussed below.
Mixed Liouor Suspended Solids
Samples of MLSS should be collected from the effluent end of the
reactor basin twice daily and analyzed for suspended solids. This analysis
will measure the total amount of solids in the aeration system. The
concentration of the MLSS, which depends on the influent 8005 concentration,
should be adjusted based on the daily average.
Mixed Llouor Volatile Suspended Solids (MLVSS)
Each MLSS sample should be analyzed for MLVSS. This analysis indirectly
measures the living biological percentage of the MLSS. The concentration of
MLVSS is normally 70 to 80 percent of the concentration of the MLSS.
Dissolved Oxygen
The concentration of dissolved oxygen in the reactor basins should be
measured twice daily to ensure that a concentration of 1-3 mg/L is main-
tained. Samples should be collected about 2 ft below the surface of the
reactor basin, near the effluent weir. .The plant operator should adjust the
air supply to provide more air if the dissolved oxygen concentration is less
than 1 mg/L and less air if it is greater than 3 mg/L.
E-16
-------
TABLE €-4. PILOT PLANT MONITORING SCHEDULE
Sampling Point
Parameters3
Frequency
Primary Effluent
MLSS
WAS/RAS
Secondary Clarifier
Final Effluent
Temperature
pH
SS
BOD5
Overflow rate
CBOD5
Temperature
PH
Dissolved oxygen
Respiration rate
Sludge volume index
SS
VSS
Microscopic examination
SS
Sludge blanket depth
Temperature
pH
Settleable solids
SS
BOD5
CBOD5
1 grab daily
1 grab daily
4 grabs weekly and
3 24-h composites weekly
3 24-h composites weekly
1 grab daily
1 24-h composite weekly
1 grab daily
1 grab daily
2 grabs daily
2 grabs daily
2 grabs daily
1 grab daily
1 grab daily
1 grab daily
1 grab daily
2 grabs daily
1 grab daily
1 grab daily
1 grab daily
4 grabs weekly and
3 24-h composites weekly
3 24-h composites weekly
1 24-h composite weekly
a SS = Suspended solids; 8005 = 5-day biochemical oxygen demand; CBODc =
5-day carbonaceous biochemical oxygen demand; VSS = volatile suspended
solids.
E-17
-------
Sludge Volume Index (SVI)
The rate at which the MLSS settles in the settling basin depends on the
sludge characteristics. These characteristics are described by a simple
settling test: 1,000 mL of the MLSS effluent is collected and allowed to
settle for 30 min in a Mai lory settleometer. At the end of 30 min, the
volume of the settled sludge is measured. The SVI is calculated as follows:
CUT volume of settled sludge (ml) x l.QOQ
bvi = MLSS (mg/L)
The lower the SVI, the more dense the sludge. An SVI of 150 or less is
usually considered good.
Sludoe Density Index (SDI)
The SOI test is also used to indicate the settling characteristics of
the sludge, and it is arithmetically related to the SVI:
SDI
bui SVI
SDI of a "good settling sludge" is about 1.0. A value of less than 1.0
indicates light sludge that settles slowly. An index greater than 1.5
indicates dense sludge that settles rapidly.
Organic Loading
From routine laboratory 8005 analysis, the plant operator can determine
organic loading in the reactor basin.
Organic loading = (Ib BOD/ 1,000 ft3/day)
on-ru cffT,,on+ Dfin (mn/t\ v PQTW Effluent Flow (MGD) x 0.0624
POTW Effluent BOD (mg/L) x Reactor Basin Volume (MG)
E-18
-------
Return Activated Sludge (RAS) Flow Rate
To properly operate the activated sludge process, an MLSS that settles
adequately must be achieved and maintained. The MLSS are settled in the
settling basin and then returned to the reactor basin as RAS. The RAS
allows the microorganisms to remain in the treatment system longer than the
flowing wastewater. Changes in the activated sludge quality and settling
characteristics will require different RAS flow rates.
Two basic approaches can be used to control the RAS flow rate. One
approach establishes a constant RAS flow rate, independent of the influent
flow. This approach is simple (i.e., maximum solids loading in the
settling basin occurs at the start of the peak flow periods) and less
operator attention is needed. A disadvantage of this approach is that the
F/M ratio is constantly changing. However, because of short-term variation
in the MLSS due to hydraulic loading, the range of fluctuation in the F/M
ratio is generally small enough to ensure that no significant problems
arise.
A second approach establishes the RAS flow rate as a constant percentage
of the influent flow. This approach reduces variations in the MLSS
concentration and the F/M ratio, and the MLSS remain in the settling basin
for shorter time periods (which may reduce the possibility of denitrification
in the basin). The most significant disadvantage of this approach is that
the settling basin is subjected to maximum solids loading when the basin
contains the maximum amount of sludge, which produces excessive solids in the
effluent.
Two methods are commonly used to determine the RAS flow rate. The
settleability method uses the settled sludge volume from the SVI test to
calculate the RAS flow rate:
E-19
-------
RAS Flow Rate (MGD) •
Volume of Settled Sludge (mL) x FPOTW Effluent HOW MP)1
The second and more direct method Is to monitor the depth of the sludge
blanket in the settling basin. The depth of the sludge blanket should be
less than one-fourth of the water depth of the settling basin sidewall.
The operator must check the sludge blanket depth twice daily, adjusting the
RAS flow to control the blanket depth. If the depth of the sludge blanket is
increasing, increasing the RAS flow is only a short-term solution.
Increases in sludge blanket depth may result from too much activated sludge
in the treatment system, a poorly settling sludge, or both. If the sludge
is settling poorly, increasing the RAS flow may cause even more problems
by further increasing the flow through the settling basin. Long-term
corrections noted below must be made to improve the settling characteristics
of the sludge or remove the excess solids from the treatment system:
• If the sludge is settling poorly because of bulking, the
environmental conditions for the microorganisms must be
improved
• If there is too much activated sludge in the treatment system,
the excess sludge must be wasted.
The best time to measure RAS flow is during the period of maximum daily
flow, because the clarifier is operating under the highest solids loading
rate. Adjustments in the RAS flow rate should be needed only occasionally
if the activated sludge process is operating properly.
Waste Activated Sludge (WAS) Flow Rate
The increase of activated sludge is a cumulative process that eventually
produces surplus WAS. This surplus has to be permanently removed from the
treatment process and collected for ultimate disposal. The WAS flow rate
should be determined and adjusted daily to maintain the desired mean cell
E-20
-------
residence time (MCRT), based on the MLSS in the entire secondary system, and
RAS suspended solids concentration:
[Aeration Tank Volume (MG) +
WAS now Rate (WD) - MLSS (ng/L) x
[RAS Suspended Solids (mg/L)]
Mean Cell Residence Time (MCRT) /Sol ids Retention Time (SRT)
The MCRT, which is also called the SRT, is a measure of the age of
sludge. Under normal conditions, the MCRT is 5-15 days. MCRT is defined as:
Suspended solids in total secondary system Mb)
Solids wasted (Ib/day) + effluent solids (Ib/day)
FMLSS fmo/DI x [Aeration Tank Volume(MG) + Secondary Clarifier Volume(MG)1
[WAS Suspended solids (mg/L) x WAS Flow (MGD)] +
[Effluent Suspended solids (mg/L) x Effluent Flow (MGD)]
MCRT is the best process control technique available to the plant
operator. By using the MCRT, the operator can control the quantity of food
available to the microorganisms and calculate the amount of activated
sludge that should be wasted.
Food/Microoraam'sm Ratio (F/M)
The F/M ratio is the ratio of BOD in the POTW effluent to the MLVSS.
An F/M ratio of 0.15 to 0.4 is desirable. F/M is defined as:
PQTW Effluent BOD (mo/L)
MLVSS (mg/L)
To control the F/M ratio, the operator must adjust the MLSS by wasting more
or less sludge.
E-21
-------
Temperature
In process control, accurate temperature measurements are required to
predict and evaluate process performance, thereby enhancing microbial
growth. Typically, the rate of microbial growth doubles for every 10° C
increase in temperature within the specific temperature range of the
microbe.
Hydrogen Ion Concentration (pH)
The activity and health of microorganisms is affected by pH. Sudden
changes or abnormal pH values may indicate an adverse industrial discharge.
A pH drop will also result when nitrification is occurring in a biological
process; alkalinity is destroyed and carbon dioxide is produced during the
nitrification process.
Respiration Rate
The efficiency of the activated sludge process depends primarily on
the activity of bacteria that use organic compounds in sewage for energy
and reproduction. When in contact with an adequate food supply, viable
bacteria will have a respiration rate (i.e., oxygen uptake rate) of 5-15 mg
oxygen/h/g MLSS. Respiration rate data provide immediate information
concerning viability, nitrification, organic loading, nutrient levels, and
toxicity in the activated sludge.
c
The respiration rate, or oxygen uptake rate, is monitored with a
dissolved oxygen meter over a time interval (t) (e.g., 6-10 min). The
respiration rate is a measure of the decrease in dissolved oxygen concen-
tration:
RR (mg oxygen/h/g MLSS) = [DO change over t (mo/DI x [60.0001
[MLSS (mg/L)] x [t (min)J
E-22
-------
Microscopic Examination
Microscopic examination of the MLSS can be used to evaluate the
effectiveness of the activated sludge process. The most important micro-
organisms are the protozoa, heterotrophic bacteria, and autotrophic bacteria
responsible for purifying the wastewater. Both protozoa (e.g., ciliates)
and rotifers are indicators of treatment performance, and large numbers of
these organisms in the MLSS indicate good quality sludge. Large numbers of
filamentous organisms and certain ciliates indicate poor sludge quality, a
condition commonly associated with a sludge that settles poorly (i.e, the
sludge floe is usually light and fluffy because it has a low density). Many
other organisms in the sludge (e.g., nematodes, waterborne insect larvae)
may be found in the sludge. However, these organisms are not significant to
the activated sludge process.
E-23
-------
TOXIC POLLUTANT MONITORING PROGRAM, TESTING PROCEDURES,
AND QUALITY ASSURANCE/QUALITY CONTROL (QA/QC)
A sampling strategy must be developed to estimate the difference
between toxic pollutant concentrations in the existing discharge and those
in the secondary treatment pilot plant discharge. Samples must be collected
using proper techniques and analyzed using appropriate analytical methods.
Both field and laboratory methods must be performed under defined QA/QC
procedures.
Applicants are referred to the following documents for guidance on
specific topics relevant to the design and execution of 301(h) monitoring
programs:
• Sampling/Monitoring Program
NPDES Compliance Sampling Manual (U.S. EPA 1979a)
Design of 301(h) Monitoring Programs for Municipal
Uastewater Discharges to Marine Haters (U.S. EPA 1982a)
Handbook for Sampling and Sample Preservation of Water
and Uastewater (U.S. EPA 1982c)
• Chemical Analytical Methods
Methods for Chemical Analysis of Uater and Wastes (U.S.
EPA 1979b, revised 1983)
Guidelines Establishing Test Procedures for the Analysis
of Pollutants [40 CFR Part 136 (1984)]
E-24
-------
Standard Methods for the Examination of Water and
Hastewater (16th ed.) (American Public Health Association
1985)
Analytical Methods for EPA Priority Pollutants and
301(h) Pesticides in Estuarine and Marine Sediments
(Tetra Tech 1986a)
Analytical Methods for EPA Priority Pollutants and
301(h) Pesticides in Tissues from Estuarine and Marine
Organisms (Tetra Tech 1986b)
• Quality Assurance/Quality Control (QA/QC)
Handbook for Analytical Quality Control in Hater and
Uastewater Laboratories (U.S. EPA 1979c)
Quality Assurance/Quality Control (QA/QC) for 301(h)
Monitoring Programs: Guidance on Field and Laboratory
Methods (Tetra Tech 1987).
Information from these documents is summarized below.
SAMPLING FREQUENCY
The frequency of sampling is dependent on the characteristics of the
discharge (e.g., influent and effluent toxic pollutant variability, flow,
size and location of the discharge). For example, large applicants with
substantial quantities of toxic pollutants should conduct more frequent
sampling than small dischargers with fewer toxic pollutants. Also, if
existing toxic pollutant data are minimal, and estimates of periods of
maximum pollutant loadings and peak concentrations are not known, then more
frequent monitoring is needed.
E-25
-------
The concentrations of toxic pollutants in the discharge may vary in
response to periodic peak inflows. If a fixed periodic trend is observed
(e.g., a sine curve) the sampling plan could be designed to collect samples
during the peak period.
If a fixed sampling interval is chosen that is equal to or a multiple
of the period, every sample would be taken at the same inflow condition and
the estimate of the mean difference in toxic pollutant concentrations
between samples would not take into effect all possible inflows. The most
favorable sampling situation occurs when the fixed sampling interval is an
odd multiple of the half-period (i.e., successive deviations above and below
the mean inflow would mathematically cancel one another, and the mean
difference in concentration between samples would take into effect the mean
inflow). However, toxic pollutant effluent data from the applicant may not
be sufficient to identify the odd multiple of the half-period. In this
case, a fixed sampling interval would not be recommended.
Assuming that the toxic pollutant limits for the POTW will be based on
the pollutant concentrations measured in the secondary treatment effluents,
a flexible sampling scheme for secondary treatment pilot plant effluents may
involve sample collection for 1 day/wk (over 24 h) on different days of the
week over a 1-yr period of pilot plant operation. This flexible sampling
frequency would generate a data set that represents an acclimated biological
treatment system. It would also address the day/night, weekday/weekend, and
seasonal variations in domestic, industrial/commercial, and wet- and dry-
weather discharges.
SAMPLE COLLECTION AND ANALYSIS
Representative samples must be collected to ensure that data are
reliable. Care must be taken to select appropriate sampling devices and
procedures. Depending upon the toxic pollutant to be analyzed, three types
of samples may be collected:
E-26
-------
• Grab sample - a discrete sample volume is collected. (This
type of sample will not always provide an accurate measure
of wastewater characteristics, particularly when the flow or
pollutants are heterogeneous or vary with time.)
• Simple composite sample - equal sample volumes are collected
sequentially overtime and combined in a single reservoir.
(This type of sample does not measure the mass of pollutants
discharged, because pollutant loading is a flow-related
value.)
• Flow-proportioned composite sample - incremental samples are
collected over time and sample volumes are proportional to
flow. Incremental samples are combined in a single reservoir.
(This type of sample provides the most accurate measurement
of wastewater quality and pollutant loading.)
The methods to be used for the analysis of toxic pollutants are
summarized in Tables E-5, E-6, and E-7. Grab samples for volatile organic
compounds, total recoverable phenolic compounds, and cyanide should be
collected manually at least four times during the discharging period of the
POTW during a 24-h period (e.g., at least every 6 h within a 24-h period,
assuming continuous discharge). Samples for all other variables should be
collected using an automatic sampler. The automatic sampler should collect
a selected number of sample aliquots (minimum of 100 ml each) during the
discharging period of the POTW. Recommended sample sizes, containers,
preservation techniques, and holding times are shown in Table E-8. Sample
analyses will generally be completed by the analytical laboratory within
4-6 wk; data analyses will generally require an additional week. Interpre-
tation of all data collected at the pilot plant during 1 yr will require
about 2 wk.
E-27
-------
TABLE E-5. LIST OF TEST PROCEDURES APPROVED BY U.S. EPA
FOR INORGANIC COMPOUNDS IN EFFLUENT
Note: This table is an exact reproduction of Table IB in 40 CFR 136.3,
Parameter, units, and method
2. Alkalinity, a« CaCCs mg/L
to pH 4.5. manual, or.
Automated
3. Aluminum— Total ' mg/L: Digestion '
followed by:
AA direct aspramn
AA tumaca
inductively coupled plasma or
4 Ammonia (•» N). mg/L: Manual distil-
lation (at pH 9.5) » followed by:
Nestienzation
Titration
Electrode
Automated pnenate or
Automated aiecuode
5. Antimony— Total *. mg/L. Digestion "
followed by:
AA dvect asp*aMn
AA furnace or ,
influcimi) coupled plasma
6 Arsenc— Total ». mg/L: Oigesuon *
followed by
AA gaseous hydnde
M furnace
inductively coupled plasma, or
Colonmetnc (SOOC)
7 Banum— Total ». mg/L Digestion » fol-
lowed by:
AA direet aspiration
AA furnace, or
inductively coupled plasma
8. Beryllium— Total '. mg/L Digestion *
followed br
AA direct aspratjon
AA furnace. ..
inductively coupled plasma, or
9. Biocftemeal oxygen demand (BOO •).
mg/L
Dissolved Oxygen Depletion
10. Boron— Total. mg/L
Colonmetnc (curcumm)
or inductively Coupled plasma
11 Bromide. mg/L Titnmetnc
12. Cadmium— Total '. mg/L. Digestion »
followed by:
AA direct aspiration
AA furnace
inductively coupled plasma
vottametry " or
Colonmetnc (Ditntzone)
13 Calcium— Total *. mg/L. Digestion9
followed by
AA direct novation
Reference (method No or page)
EPA 1979
30* 1
310 1
310.2....
202.1
2022
350 2
350.Z
3S0.2
350.3
350.1
204.1
204.2.....
206.5
206.3
206.2
206.4
208.1
208.2
210.1
210.2....
405.1
212.3
320.1
213.1
213.2...
215.1
Standard
metfiods
iem Ed.
40.2(4 •)
403
303C
304
3068
41 7A
4178
4170
417EOTF...
41 7G
303A
304
303E
304
307B
303C
304
303C
304
309B
507
404A
303 A or 8.
304
3108
i
! 303A
ASTM
1067-«2(E)
Ol067-«2(8)
01 426-791 A)
01426-79(0)
01426-79
-------
TABLE E-5. (Continued)
Parameter units, and method
Reference (method No or page)
Standard
EPA 1979 methods ASTM USGS ' Otner
'6th Ed
inductively coupled Bi»»m». or
T.tnmeinc (EDTA) 2152
'4 Caroonaceous biochemical oiygen
demand ICBOO .). mg/L " Dissolved
Oxygen Oeoienon with mtntication m.
hibitor
iS Chemical oxygen demand (COO).
mg/L.
Titnmetnc Of • • 410. i
Spectropnotomemc. manual or auto-
mated.
16. Chlonde. mg/L.
Titnmetnc (silver nitrate)
or (Mercuric nitrate) or
Automated (Femcyanide)
1 7 Chionne— Total residual. mg/L.
Titnmetnc:
Amperometnc direct
Slarcn end point direct
Back mration either end
point 14. or
OPD-PAS
Spectropnotometnc OPO
Or Electrode
18 Chromium VI dissolved. mg/L 045
micron filtration followed by:
AA cneiatjon-extracuon. or
Cotonmetnc (Dipnenyicarbazide)
19 Chromium— Total ]. mg/L. Diges-
tion •• followed by:
AA direct aspiration
A A cneianon extraction ..
AA furnace
inductively coupled plasma or
Coionmetnc (Dtpnenylcaroaittfe)
20 Cobalt— Total '. mg/L Digestion '
followed by:
AA direct aspiration
AA *umace or
i~" icttveiy coupled plasma
21 Ccor platinum cobalt uruts or dorm-
nant wavelength, hue. luminance
punty:
Coionmetnc (AOMI). or
(Platinum coMR) or
22 Copper— Total3 mg/L Digestion-" fol-
lowed by:
AA direct aspiration
AA furance
inductively coupled plasma.
Coionmetnc (Neocuprotne) or
(Bicincnontnate)
23 Cyanide— Total. mg.L: Manual distil-
lation with MgO: followed by
Titrimetnc or
410.2. or
4103
4104
32S.3
3251. or
3252
330 1
3303
3302
311C...
S07(5e.6)
508A
407A .
4078
4070
408C
408A
4oaa
330.4 4MD
3305
ATMf
i
218.4
218.1
2183
218.2..
219 1
2192
110 1
110.2
110 3
220.1
2202
3038
303A
3038
304
3128
303 A or B...
304
2040
204A
2048
303 A or 8...
304.
3138..
0511-841 A)
01252-83
0512-81(8)
OS 12-81 (A)
0512-81(0).. ..
D12S3-76
Notes 12
33.067 >
Note 15
3078."
33.089.'
200. 7 «
P 37 •
200.7 «
Note 17
33.089'.
200.7."
Note 18.
p. 22.'
P. 17 •
or 13
P 37 •
E-29
-------
TABLE E-5. (Continued)
Parameter units, and metnoa
Deference (memod No. or page)
• Standard : : :
EPA 1979 ; metnods - ASTM ! USGS ' I
i • 16m 6d' ; ! j
Otner
24 Cyandie amendable to cnioonation.
mg/L Manual distillation with MgCl.-
followed by titnmetnc or spectropnoto-
meinc
25 Fluonde — Total, mg/L. Manual distil-
lation • followed by
Electrode, manual or .
Automated
Cofonmetnc (SPAONS)
Or Automated compierane
26 Gold— Total3. mg/L Digestion* fol-
lowed by:
AA direct aspiration or
AA furnace
27 Hardness— Total, as CaCOj mg/L
Automated coKximetnc
Titnmetnc (EOTA) or Ca plus Mg as
mew carbonates, by inductively
coupled plasma or AA dvect asp*-
radon. (See Parameters 13 and
33)
26. Hydrogen ion (pH). pM units:
Electrometnc measurement, or
Automated electrode
29 inoiunn— Total-'. mg/L Digestion'' fol-
lowed by:
AA d*eact aspiration or
AA fumaff*
30. iron— Total1. mg/L. Digestion-1 fol-
lowed by
AA direct aspiration
AA furnace
inductively coupled plasma, or
31 Kjettam nitrogen -Total (as N). mg/
L. Digestion and distillation followed
by:
Titration
NessienzaMn
Automated pnenate
Semi-automated (Mock digestor or
Potentiometnc
32 Lead— Total ;l. mg/L. Digestion •• fol-
lowed by
AA direct aspiration
AA furnace
inductively coupled plasma
Voitametry '" or
Coionmetnc (Ditnizone)
uon ' followed by-
AA direct aspiration '.
inductively coupled plasma, or .
Gravimetric
34 Manganese— Total '. mg/L. Diges-
tion ' followed by:
AA direct aspiration
A A furnace
inductively coupted piasma. or
Coionmetnc (Persuitatei. or
iPenodatei
335.1
340.2
340.1
340.J
231 1
231 2
1301
1302
ISO 1
235 1 ...
2352.
2361 .
2302.
351 3
351 3.
351 3.
351.3... ..- .
351.1
351 2
351 4
239 1
2392
242.1
243 1..
243 2
412F
413A
4138
413C
4136
303A
304
3148
423
303A ...
304
303 A or 8..
304
3158
420 A or 8
4170
4178
417 E or F
303 A or 8
304
3168
303A
3188
i 303 A or 8
304
, 3198
02036-82(8)
.
01179-80(9)
01179-80(A)
01126-80
01293-84 (A
or 8).
01088-84 (C
orO).
01086-64
-------
TABLE E-5. (Continued)
Rafaranca (method No. or paga)
Paramatar. units. and fnatnod
EPA 1979
Standard
ASTM
USGS>
OttMT
35. Marcury— Total ». mg/L
CoW vapor manual or
Automatad
36. Molybdanum— Total '. mg/L Oigaa-
don> followed by
AA diract aapration
AA fumaca of ....
37. Nick* Total'. mg/L DtgaaOon •
followad by
AA diract aapntton
AA fumaea
3>. Nitrata •«• N) mg/L CotorimaMc
(Bruon* ,.«ata). or Nftata-nima N
MWM^ klitHA 84 /C^M •^•MMMfc^tf^MM 1O
mtnUB mm* ra (9OT pranwrv *jv
and 40).
»M1H«I« i alula Im* Nl im/l • r^tormm
raduetton. Manual or
Automatad. or
40. Nima (aa N). mg/L 3o«cttoprio l^a^^4^«
«o, wxygan ovaoivaa« (no/L* wwviaf
iAfldai niodMcatton), or
C!A«MBMM«A
47. Palladium— ToM *. mg/L Olaanon •
feiio»ad by
AA fumaea
48. Pnanola, mg/L
Manual fHaWailon *•
FoHOwao oyt
rpionmaaic (4AAP) manual, or....
Automatad l*
49 Phoaonorm (atamantaO mg/L Qaa*
50. Phoapheru*— Total. mg/L Parauifata
j^^^at^MK f«yb^^^H4 Itej
ui^Hmon TuH^^iQ Dy
Manual or
Automatad aanonjic aod 'tiluction
or.
Samhautomatad Mock dtoaattr
245.1
245.2
240 1
24&2.
248.1
249.2.
352.1
1533
353.2,
353 1
354.1 _..
413.1
415.1 .
306.1
38&Z
HW3
2521
2522.
380.1
253.1
253.2,
420.1
420 1
420.2.
306^.
305^ or
305.3.
3051
305.4
303F
303C
304
303 A or B...
304
321 B
418C
410F...
419
503A
505
424Q.. .
424F
303C
304
4218
421 F
424C0II)
424P
424G
03223-60
01686-64 (C
orO).
0992-71
03067<45(B)
O3667-65(A).
01254-07.
02579.85 (A or
B).
DS15-62tA) ..'..
0688-61 (C)
01783-60 (A
orB).
0515-62(A).
1-3462-84
1-3490-64
1-3499-64
1 «645 64
1-4540-64
M601-64
1-1575-78 '
1-1 576-78 f
I-4600-64
33095 *
200 7 4
2007*
33083* 4190 '•
p. 28.*
Nota 24
33.044 » p 4 "
33 118 '
33 111 *
33.028.'
P S27*
P. S28.»
Nott 26.
Nota 27.
33.111.'
33.116*
E-31
-------
TABLE E-5. (Continued)
Pwntttr, units, And nwttiod
toftowadby:
AA diract •Tr"*"'*"" or
AA fumaca ,
52. PoUMMfn toui*. mg/L Ogotien
foaowadby:
AA dkact aspiration
Rama photornatnc. or
S3 Raariua — Total mg/L Gnrnmatnc
103-105'C.
M Raaidua — (WaraMa mg/l: Onvinx
me, iBO'C.
^ Heart* — nonfUtaraMa (TSS) mg/L:
Gravwnamc, 103-105'C poat waahing
57. P.i»jdui Volatta. mg/L Gravwna-
BitSSO'C.
56. Rhodium— Total *. mg/L Oigarton'
loNMvadby:.
AA fumaca
IM^H • 0Mll«ta«^M4 >^^>
oon • lOnowao oyr
AA lumaca
60. Satanum— Total '. mg/L OigaMon *
(olioaad by
AA fumaca
AA gaaaoua ftydnda
61 Silica— Oitaolvad. mg/L 0.45 micren
Kllfation tottowad by:
Cotonmatnc, Manual or
*utnrw«rt (Mnt>oan>iliean) or
62. Silvar— Total '*. mg/L Oigarton »
toltowadby:
AA olract Mention
AA lumaca
63. SodNjm— Total *. mg/L Oigarton'
foliowadby:
inducttvaly eauplad piaima. or
Flama pnotomatnc
64. Seacrfic conductanca. mcromhoa/
cm at 25'C: Whaatttorta bndga
65. Sutfata (aa SO.). mg/L
Automatad colonmatnc. (banum
craorarMata).
Grawimatnc. or
Tufbidimainc
EPA 1979
255 1
255A
288.1
iao.3
160.1..-
1602.
160.5
160.4
265.1
26S.2.
267.1..
2672..
270.2.
270.3
370.1
272.1
272.2.
273 1
120.1
375.1
! 3753
375.4
Ra
StWtaVd
H^a^tWM4ai
nwinom
letnEd.
303A
304
303A
?229
209A
209B
209E
2090
303A
304
303A
304
304
303E
425C
303 A or 8
304
303A
32SB
205
426 A or B
laranca {mainod I
ASTM
D1428-82(A)
*••.••••••••••••••••••*•••••••
03859-64
1-3630-64
1-3750-64
1-1750-64
1-3765-64 ....
1 _ _
1-3753-64
1-3667-64
1-1700-64
I-2700-64
1-3720-64
1-3735-64 . . ..
1-1780-64
i
Omar
33.103.'
2007*
31 78 '•
2007*
200.7.«
33.089 *. p. 37.*
3198.'*
200.7*
33.107 »
200.7.*
33.002.'
' 33.124 *
426C .»•
Trtnmatnc (iodma) or .............................. ! 376.1 .............. | 4270 ........................................... : I-3840-64 ........... 228A."
Colonmatnc (mathylana Mua) ............... ! 376.2 .............. ! 427C [[[
67 Suffita (at SO,). mg/L Trtnmatnc ; 377.1 .............. ; 426A ............. 01339-84(C) ...................................
((Odtna-iodata)
68 Surtacunts. mg/L: Colonmatnc : 425.1 .............. .5128 ............. 02330-82IA). ' .............
69 Tempcratura. 'C.. Thannomatnc
170.1
-------
TABLE E-5. (Continued)
Reference (method NO or pagei
Parameter, units, and method
Standard
EPA 1979 methods
i6tn Ed.
ASTM
USGS'
Other
70 Thallium—Total'. mg/L. Digestion >
followed by:
AA direct aspiration 279.1 303A :
AA fumsce. or 279.2 304 ;
inductively coupled plasma , ; 200.7 <
71 Tin—Total1. mg/L DigestionJ fol- ' ; ;
lowed by: • '
AA direct aspiration, or j 282.1 ; 303A i ; I-3850-78 ' :
AA furnace i 282.2 : 304 i | |
72. Titanium—Total'. mg/L Digestion3 i ' • , :
AA direct aspiration, or
AA furnace
73. Turbidity NTU- Nephetometnc
74. Vanadium. Total 3. mg/L Digestion *
followed by:
AA furnace
Cotonmetnc (Gallic acid)
75. Zinc-Total3. mg/L Digestion' fol-
lowed by:
AA furnace
(Zncon)
283.1
283.2
180.1
288.1
288.2
289.1
289.2
303C
304
214A
303C
304
3278
303A or B....
304
328C
01889-81
D3373-«4e effluent sampiea are on company We to show that
this prekmnaiy distillation step • not neeeaaary: however, manual distiBaoon win be rrjured to resolve any controversies.
•Ammona. Automated Electrode Method. Induamal Method • Number 379-75 we dated February 19. 1978. Techncon
AutoAnaryzer II. Techncon induatneJ Systems, Tarn/town. NY. 10591.
'The approved method is that cited m "Methods for Determination of Inorganic Substances in Water and Fluvial
2. 1975. AvaMMe from ANSI. 1430 Broadway,
Supplement to
Sedimema". USGS TWAI, Book 5. Chapter A1 (1979).
• American National Standard on Photographic Pnxaeamg Effluents, Apr.
New York. NY 10018.
• "Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency.
the Fifteenth Edition of Stanoavtf «ee*ioa» for tttt £xmmfitHofi of Wit* tnd WMMwemr (1981).
18 The use of normal and differential putaa voltage ramps to increase sensitivity and resolution is acceptable.
1 ' Caroonaceous tuochemcal oxygen demand (CBOO.) must not be confuaed with the traditional BOD, test which measures
•total BOO." The addition of the nuiUcauuii inhibitor is not a procedural option, but must be included to report the CBOD,
parameter. A discharger whose permit requires reporting the traditional BOO. may not use a nnnfication mnfcrtor in the
procedure tor reporting the results^ Only when a discharger's permit specifically states CBOO. is required, can the permittee
report data using the nrtnfication wihibrtor.
E-33
-------
TABLE E-5. (Continued)
'- QIC Chemical Oxygen Demand Method. Oceanography international Corporation. 512 West Loop. P.O. Box 2980. College
Station. TX 77840
"Chemical Oxygen Demand. Method 8000. Hach Handbook of Water Analysis. 1979. Hach chemical Company. P.O Box
389. Loveiand. CO 80537
1' The back titration method will be used to resolve controversy.
'••Onon Research instruction Manual. Residual Chlorine Electrode Model 97-70. 1977. Onon Research incorporated. 840
Memorial Drive. Cambridge. MA 02138.
'" The approved method « that cited m SunOard Mamoat tor ma Examination of Watar ana Wattawatar. 14th Edition.
1976.
17 National Council ol the Paper Industry tor Air and Stream improvement, (inc.) Technical Bulletin 253. December 1971
'"Copper. Biocmchomate Method. Method 8506. Hach Handbook of Water Analysis. 1979. Hach Chemical Company. P0
Box 389. Loveiand. CO 80537.
'• After the manual drstHlaton * completed, the autoanaiyzer manifolds in EPA Method* 335.3 (cyanide) or 420.2 (phenols)
are simplified by connecting the re-sample hne oveetty to the sampler. When using the manifold setup shown m Method 335.3.
the buffer 6.2 should be replaced with me buffer 7.6 found m Method 335.2.
"Hydrogen ion (pH) Automated Electrode Method, industrial Method Number 378-75WA. October 1976, Techmcon Auto-
Analyzer II. Techmcon industrial Systems. Tarrytown. NY 10591.
" Iron. 1.10-Phenanthrotme Method. Method 8008. 1980. Hach Chemical Company. PO. Box 389. Loveiand. CO 80537
" Manganese. Penodate Oxidation Method. Method 8034. Hach Handbook of Wastewater Analysis. 1979. pages 2-113 and
2-117. Hach Chemical Company. Loveiand. CO 80537.
" Goerhtz. D.. Brown. E.. "Methods for Analysis of Organc Substances in Water." U.S. Geoiogwal Survey Techniques of
Water-Resources Inv.. book 5. ch A3. page 4 (1972).
" Nitrogen. Nrtnte. Method 6507. Hach Chemical Company, P.O. Box 389. Loveiand. CO 80537.
" Just pnor to dmtillation. adiust the suHunc-acid-preserved sample to OH 4 with 1 * 9 NaOH.
" The approved method is that cited m Standard UatnoOt for ma Summation of Watar ana Waatawatar. 14th Edition. The
cokximetnc reaction « conducted at a pH of 10.0=0.2. The approved methods are given on pp. 576-81 of the 14th Edition:
Method 510A tor distillation. Method 5106 for the manual cokximetnc procedure, or Method 510C for the manual
spectrophotometnc procedure.
" R. F. Addison and R. G. Ackman. "Direct Determination of Elemental Phosphorus by Gas-Liquid Chromatography."
Journal of Chromatography. vol. 47. No. 3. pp. 421-426. 1970.
"Approved methods for the analysis of stiver m industrial wastewaters at concentrations of 1 mg/L and above are
inadequate where silver exists as an morganc halide. Silver haMes such as the bromide and chloride are relatively insoluble in
reagents such as ratnc aod but are readily soluble m an aqueous buffer of sodium ttvosuitate and sodium hydroxide to a pH of
12 Therefore, for levels of sliver above 1 mg/L 20 mL of sample should be dduted to 100 mL by adding 40 TIL each of 2 M
NajSjOj and 2M NaOH. Standards should be prepared m the same manner. For levels of silver below 1 mg/L the approved
method is satisfactory
»* The approved method * that cited in Standard MamoOa lor ma Examination ol Watar ana Wastawatar. 15th Edition
10 The approved method is that cited in Stanoara UathoOs lor tha Examination ol Watar ana Wastawatar. 13th Edition
:
-------
TABLE E-6. LIST OF TEST PROCEDURES APPROVED BY U.S. EPA
FOR NON-PESTICIDE ORGANIC COMPOUNDS
Note: This table is an exact reproduction of Table 1C in 40 CFR 136.3.
EPA Method Number
farameier
1 Acenaphthene
2 Acenaphthyiene
3 Acrolein
4 Acrytomtnie .. . .
5 Anthracene
6 Benzene
7 Benzidine
8 Benzo(a)anthracene
9 Benzo(a)pyrene
10. Benzo(b)tluoranthene
11 8enzo(g h Operyiene ....
12 Benzo(k)fluoranthene
13 Benzyl chloride
14 Benzyl butyl phthaiate
15 8is(2-chioroethoxy) methane
16 Bis(2-chioroethyi) ether
17 B«(2-ethyihexyi) pmnaiate
1 8 Bromodichlorometnane
1 9 Bromotorm
20 Bromomethane..
21 4-Bromopnenyiphenyi ether .
22 Carbon tetracnioride
23 4.Chloro-3-methylphenoi ...
24 Chiorobenzene
25 Cnioroemane
26 2-Chioroethyiwinyi ether
GC
610
610
603
603
610
602
610
610
610
610
610
L . ..
606
611
611
! 606
601
601
601
611
601
! 604
601.602
'; 601
! 601
QC/MS
625. 1625
625 1625
'624 1624
•624. 1624
625. 1625
624 1624
'625. 1625
625. 1625
625 1625
625. 1625
625. 1625
625. 1625
625 1625
625 1625
625 1625
625. 1625
624 1624
' 624 1624
624 1624
625. 1625
624. 1624
625. 1625
624. 1624
i 624. 1624
' 624. 1624
HPLC
610
610
610
605
610
610
610
610
610
uiner
Note 3. p. 1 :
Note 3 p 130:
Note 6. p.
Si 02.
Note 3. p 130
Note 3. p 130.
E-35
-------
TABLE E-6. (Continued)
'arameter
27 Cnioro'O"Ti
28 Chiorometnane
29 2-Chioronapmnai«ne
30 2-Oloroontnol
31 4.Chioropn*nyipn*nyl etn*r
32 Chryscn* ...
33 Oib*nzo(a.n)antnractn«
34 Oibromocnioromcman*
35 1 2-Oicnioroo*nz*n* :
36. i 3-OcriioroD«nx*n*
37 1 .4.0icniorOD«nz*n« . :
38 3.3 -OicnforoMnzidir* i.
39 Dicnioroditiuoronia'than*'
40 i i -Dicnioro*tnarw
41 1 2-Oichioro*iftafw i
42 1 1 -Otcfiloro«th*n*
43 trans*i 2>Dtcmoroaith*n6
44 2 4.OiCWOrOPfl*flO) i
45 i 2-OtcftiOf'ODro0"W
46 cts*i 3-OtcfMoroprop9nt>
47 trans- 1 3-DicMOfopfOp«n*
48 Ontftyi pnmaiaw ...
49 2 4-OinwflylpMnol
50. Dimmnyt pnthalat*
51 Dt-n-Outyi pnttiaJaw . .
52 Oi-n-octyi pfitnaiaw
S3 2 4-Oinitropncftol
54 2 4-Oinitrotoiu4)n*
55 2 6-Otnitrotolu*n*
56 Epicniorofiydnn
57 Etnyibsfiztn*
58 F!uorantn*n*
59 Fluorvn*)
60 H*KacMOfot)€fiza*w
6i HnacraoroouMxMn*)
62 H*iacniorocyciocnnTK)wfM
63 Hnacntofo^tfiint
64. id*no(l.2.3-cd)pyr*n*'
65 isopnoron*)
68 Mctnywnt cfttono*
67 ? UatfM.4 n anmrmti^rt
6fl NaontnaMnc
69 NrtrotMnncn*
70 I flitropmrol
71 « NilrOpfWOl
72 N-NitromUMiMiHylonifM
73 N-NitroaodHA'fvopytajfffMnc
74 14 Hiiiuiodiunlifnin<
75 22*-O«ytm(i-7Moraprapww)
78 PCB-1016
77 PCS- 1221
78 PCB- 1232 .
79 PCB- 1242
80 PCB- 1248
81 PCB-1254
82 PCB- 1280
83 P*nti£ftioroptwnol
84 PfMfwwwsn*
85 Ph«nol
88 Pyr«n«
87 237 6-T9tracfiiorod£4nzo-p'4ioxffi
88 112 2*T9tracftioro4)tf)Afl9
89 TatracniocQ«n625. 1625
825. 1625
625
625
625
625
625
625
625
625. 1625
825. 1625
625. 1625
625. 1625
»613
624. 1624
624. 1624
624. 1624
625. 1625
:::::;:...;
;
,
!
i
,
Not* 3 D 130
Not* 6. p
: S102
610
610 i
610
i
1 Not* 3. p. 130:
610
NOW 3. . 43:
Not* 3. . 43;
Not* 3. . 43;
Not* 3. . 43;
NOW 3. . 43;
NOW 3. . 43;
Now 3. .'43:
Now 3. . 140:
610
610
.... Now 3. p. 130:
..| Now 3, p. 130:
I. Not* 3. p. 130:
E-36
-------
TABLE E-6. (Continued)
92 M . 1 -Tncnioroamana
93 M .2-Tncnioroatnana
94 Tncnioroamana
95 Tncniorottuoromatnana
96 2 • 6-Tnchloropnanoi
97 Vinyl cnkjnda ..
EPA N
GC
601
601
601
601
604
601
Aamod Numoar -
GC/MS HPLC
624. 1624 [.. :
624! 1624 L. . . . Not* 3 o '30
624. 1624 {. . . . ;
624 I :
625 1625 <- ;
624. 1624 j.
Tabia 1C NOtt*
' All paramatari art axprasaad m mcrograms par irtar (»tg/U
n
sacwn 8.2 of aacn of maaa Matnoda. Additionally, aacn laboratory, on an on-oomg baaaa must spika and anaiyza 10% (5%
for Matnoda 624 and 625 and 100% tor matnoda 1624. and 1625) of an samplaa to monitor and avaluata laooratory data
quahty m accordanca witn factions 83 and 8.4 of maaa Matnoda. Wnan ma racovary of any paramatar falls outsida ma
warning limits, ma analytical raautta for mat paramatar m ma unap*ad aampia ara auapact and cannot ba raportad to
damonatrata ragutatory compkanca.
Note: Tnaaa warning iimrta ara promukjatad aa an "mtanm final acwn win a raouaat for commama."
E-37
-------
TABLE E-7. LIST OF TEST PROCEDURES, APPROVED
BY U.S. EPA FOR PESTICIDES1
Note: This table is an exact reproduction of Table ID in 40 CFR 136.3.
Paramatar MO- U
i. Aidnrt
2 Amotiyn
4. Atraton
5 Atrvm*
6. Azmpftoa mattiyi
7 Barban , ,„
8. a-8HC
9. 0-8HC
10. 5-BMC
1 1 , y-BHC (Lindana)
12 Captan
13 CarMrvl
14 Cartpphanomion
15, Chtardana ,.,, ,,..
16 Cnioroproptam
17 24-O
1$. 44-OOO
19. 4.4--O06
20. 4.4'-OOT
Matftod
QC
QC/MS
GC
TLC
GC . .
GC .
GC
TLC
GC...:
QC/MS
GC
GC/MS
GC
GC/MS ...
GC
SC/MS
GC
TLC
GC
GC
GC-MS
TLC
GC
GC
GC-MS .
GC
GC/MS
GC
GC/MS
EPA»-»
808
62S
808
•925
808
825
608
•623
608
625
608
625
608
625
608
625
608
825
Stand-
ard
Mam-
oda
!5tfi
£d
SWA
509A
SOOA
508A
509A
5098
509A
509A
509A
ASTM
03086
03088
03086
03086
03086
03086
03086
03088
03086
Othar
Nota 3. p. 7- Nota 4. p. 30.
Nota 3. p. 83: Nota 6. p. S68.
Nota 3. p. 94: Nota 6. p. Si6.
Nota 3. p. 83: Nota 6. p. S68.
Nota 3. p. 83: Nota 6 p. S68.
Nota 3. p. 25: Nota 6. p. S51.
Nota 3. p. 104; Nota 6. p. 564.
NOW 3, p. 7
Nota 3. p. 7- Nota 4 p. 30
Nota 3. p. 7
Nota 3. p. 94; Nota 6. p. 560.
Nota 4 p 30- Nota 6 p 573
Nota 3. p. 7.
Nota 3. p. 104: Nota 6. p. 564
Nota 3 p. 115 Nota 4 p 35.
Nota 3. p. 7: Nota 4. p. 30.
Nota 3. p. 7; Nota 4. p. 30.
Nota 3. p. 7: Nota 4. p. 30
E-38
-------
TABLE E-7. (Continued)
ug :
oas
ism
Ed
ASTM
om*f
21 D«m*ton-O
22 D*m*nton-S
23. Oiazmon
24 Oicamoa . ...
25 Oicnioltflthion
26 Dicnioran
27 Dicofol
28 OwWnn
29 rantnion
30 Oiwlfoton
31 Dnxon
32 EndOttJlfan 1
33 Endosultan 1 1
34 Endosuifan suifat*
35 Endrm
36 Endrm ald*nyd*
37 Ethion
38 P*nuron
39 F*nuron-TCA
40. H*ptacnior
41 H«ptacMor tpoxid*
42 isodnn.. .. . .
43 Linuron. . . ....
44 Matatrwon . .
45 Mctrnocarb
46 M*moiycnlor
4? MmacarMt*
48 M»t» .... ...
49 Monuron
50. Monuron-TCA
51. N*6uron
52 Paratfteon m*ttiyt
53. ParatfMon *tftyi
54 PCNB
55. Pwinan*
57 Piorn*pyn
59 Pfopfum
60 Propoiuf
61 5*ct)urn*ton
62 Siduron
63 Simian*
64 Strooan*
65 Sw*p
66 245-T
67 2 4 5-TP (&tv«i)
6fl T*ft)utf*ylaiin*
69 Toiapn*n*
70 Trtfluralin
GC.
iiC ..
GC .
GC
GC
GC
GC/MS
GC
GC
TLC
GC
GC/MS
GC .. .
GC/MS
GC .
GC/MS
GC.
GC/MS .. .
GC
GC/MS
GC
TLC
TLC
GC
GC/MS
GC
GC/MS
GC ..
TLC
GC . .
TLC
GC
TLC
GC
TLC
TLC
TLC
GC
GC .. .
GC
GC
GC .
GC . ..
GC
TLC
TLC
TLC ..
TLC ..
GC
GC
TLC
GC
GC
GC
GC
GC/MS .. .
GC
608
625
608
•625
608
'625
608
62S
608
'625
608
625
608
625
608
625
608
625
509A
509A
509A
S09A
509A
509A
509A
509A
509A
509A
509A
S09A
509A
509A
5096
5098
509A
509A
03086
03086
03086
03086
03086
03086
03086
03086
03086
Not* 3. 0 25: Not* 6. 0 S51
Now 3 p 25 Not* 6 p SSI
Not* 3 p 25 Not* 4 p 30
Not* 6. p S51
Note 3 P 115
Not* 4 p 30' Not* 6 p S73
Not* 3 p 7
Not* 3 p 7' Not* 4 p 30
Not* 4. p. 30: Not* 6 p S73.
Not* 3. p. Not* 6 p S51.
Not* 3 p 104 Not* 6 p S64
Not* 3 p 7
Not* 3 p 7
Not* 3 p 7- Not* 4 p 30
Not* 4 P 30- Not* 6 p S73
Not* 3 p 104 Not* 6 p 564
Not* 3 p 104- Not* 6 p S64
Not* 3. p. 7; Not* 4 p 30
Not* 3 p 7' Not* 4 p 30' Not*
6. p. S73.
Not* 4 p 30- Not* 6 p S73
Not* 3 p 104- Not* 6 p S64
Not* 3. p. 25' Not* 4 p 30:
Not* 6. p. SSI
Not* 3. p. 94- Not* 6. p S60
Not* 3. p. 7; Not* 4. p. 30.
Not* 3. p. 94; Not* 6. p. S60.
Not* 3 p. 7
Not* 3. p. 104: Not* 6. p. S64.
Not* 3. p. 104: Not* 6. p. S64.
Not* 3. p. 104; Not* 6, p. S64
Not* 3 p 25' Not* 4 p 30
Not* 3. p. 25.
Not* 3. p. 7.
Now 3. p. 83: Now 6. p. S66.
Now 3. p. 83: Now 6. p. 566.
NOW 3. p. 83; Now 6. . S68.
NOW 3. p. 104; NOW 6. . S64.
Now 3. p. 94; Not* 6. . S60.
Now 3. p. 83: Now 6. . S66.
Now 3, p. 104: Now 6. . S64
Now 3. p. 83; Not* 6. . S66.
Now 3. p. 7.
Now 3. p. t04: Not* 6. p. S64
NOW 3. p. 115; NOW 4. p. 35.
Not* 3. p. 115.
Not* 3. p. 83: Not* 6. p. S68.
NOW 3. p. 7; NOW 4. p. 30.
NOW 3. p. 7
Tabi* 10 Not*s
1 PvstiodM ar* i«t*d en tm* taw« by common n«m* (or m* conv*ni*nc* of m* r*ad*r. Additional p**nod*s may b* found
under TaOM iC. «n*r* *ntn** ar* nn*d Dy cnvrrucai nam*.
E-39
-------
TABLE E-7. (Continued)
•• The full ttit o< methods 608 and 625-are given at Appendix A. 'Test Procedures for Analysis ot Organic Pollutants o»
mis Pan '36 The standardized test procedure to oe used to determine ine method detection iimt (MOD 'or tnese test
procedures is given at Appendix S. Definition and Procedure for the Determination of tne Method Detection urnit". of this Pin
' Methods for Benzidine. Chionnated Organic Compounds. Pentachioroonenoi and Pesticides in Water and Wastewater '
US Environmental Protection Agency. September. 1978. This EPA puOiication includes thin-layer cnromatoo/apny (TLC)
methods. . •
4 Methods 'or Analysis of Organic Substances m Water." U.S. Geological Survey. Techniques ot Water-Resources
investigations. Book 5. Chapter A3 (1972).
1 The metnod may be extended to include a-8HC. 5-8HC. endosulfan I. endosulfan 11. and endrm However, when they are
known to exist. Metnod 608 is tne preferred method.
• 'Selected Analytical Methods Approved and Oted by the United Slates Environmental Protection Agency." Supplement to
the fifteenth Edition of Sttnava MftfioO* tor Me Eximinition of Winr tnd WutiwMr (1981)
: Each analyst must make an initial, one-time, demonstration of their abtdty to generate acceptable precision and accuracy
with Methods 608 and 625 (See Appendix A of this Part 136) m accordance with procedures given in section 8.2 of each of
tnese methods. Additionally, each laboratory, on an on-going basis, must spike and analyze 10% ot all samples analyzed with
Metnod 608 or 5% of ail samples analyzed with Method 625 to monitor and evaluate laboratory data quality m accordance
with Sections 8.3 and 8.4 of these methods. When the recovery of any parameter falls outside the warning limits, the analytical
results for that parameter m the unsptked sample are suspect and cannot be reported to demonstrate regulatory compliance
NOTE: These warning limits are promulgated as an "mtenm final acton with a request tor comments."
E-40
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TABLE E-8. RECOMMENDED SAMPLE SIZES. CONTAINERS. PRESERVATION.
AND HOLDING TIMES FOR EFFLUENT SAMPLES3
Minimum
Sample Size"
Measurement (ml) Contai nerc
PH
Temperature
Turbidity
Total suspended solids
Settleable solids
Floating parti culates
Dissolved oxygen
Probe
Winkler
Biochemical oxygen demand
Total chlorine residual
Oi 1 and grease
Nitrogen
Ammonia-N
Total Kjeldahl-N
Nitrate+Nitrite-N
Phosphorus (total)
Priority pollutant metals
Metals, except mercury
Mercury
Priority pollutant organic
compounds
Extractable compounds
(includes phthalates.
nitrosamlnes. organo-
chlorine pesticides.
25
1.000
100
1.000
1.000
5,000
300
300
1. 000
200
1,000
400
500
100
50
100
100
4.000
P. G
P. G
P. G
P. G
P. G
P. G
G bottle and top
G bottle and top
P. G
P. G
G only
P. G
P. G
P, G
P. G
P. G
P. G
G only,
TFE-lined cap
Preservatl ve™
None
None
Cool . 4° C
Cool . 4° C
Cool. 4° C
None
None
Fix onsite;
store in dark
Cool . 4° C
None
Cool . 4° C
H2S04 to pH<2
Cool . 4° C
H2S04 to pH<2
Cool . 4° C
H2S04 to pH<2
Cool . 4° C
H2S04 to pH<2
Cool . 4° C
H2S04 to pH<2
HN03 to pH<2
HN03 to pH<2
Cool , 4° C
0.008X Na2S2039
Store in dark
Maximum
Holding Time
Analyze Inmedlately8
Measure immediately6
48 h
7 days
48 h
Analyze immediately*^
Analyze immediately8
8 h
48 h
Analyze Immediately8
28 days
28 days
28 days
28 days
28 days
6 mo
28 days
7 days until
extraction
40 days after
extracti on
PCBs, nitroaromatics,
isophorone, polycyclic
aromatic hydrocarbons,
haloether, chlorinated
hydrocarbons, phenols,
and TCDD)
Purgeable compounds
40 G only,
TFE-lined septum
Cool. 4° C
0.008X Na2S2039
7 daysh
£-41
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TABLE £-8. (Continued
Minimum .
Sample Size"
Measurement
Total and fecal coll form
bacteria
Enterococcus bacteria
(mL)
250-500
250-500
Container0
P. G
P. G
Preservatl ve^
Cool . 4° C
0.008X Na2S2039
Cool . 4° C
0.008X Na2S2039
Maximum
Holding
6 h
6 h
Time
a Reference: Adapted from U.S. EPA (1979b), 40 CFR Part 136.
Recommended field sample sizes for one laboratory analysis. If additional laboratory
analyses are required (e.g.. replicates), the field sample size should be adjusted accordingly.
c P = Polyethylene; G » Glass.
° Sample preservation should be performed immediately upon sample collection. For 'composite
samples, each aliquot should be preserved at the time of collection. When use of an automated
sampler makes it impossible to preserve each aliquot, the samples should be maintained at 4° C
until compositing.
e Iirmediately means as soon as possible after the sample is collected, generally within 15 min
(U.S. EPA 1984).
* No recommended holding time is given by U.S. EPA for floating particulates. Analysis should
therefore be made as soon as possible.
9 Should only be used in the presence of chlorine residual.
Holding time and preservation technique for purgeable compounds are based on the use of
U.S. EPA Method 624 for screening all priority pollutant volatiles organic compounds, including
acrolein and acrylonitrile. If analysis of acrolein and acrylonitrile is found to be of
concern, a separate subsample should be preserved by adjusting the pH to 4-5 and the sample
should then be analyzed by U.S. EPA Method 603.
E-42
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QA/QC
QA/QC procedures should be detailed in the quality assurance project
plan (QAPP) (U.S. EPA 1979c; Tetra Tech 1987). The following items should
be discussed in the QAPP:
• Statement and prioritization of study objectives
• Responsibilities of personnel associated with sample
collection and analysis
• Sampling locations, frequency, and procedures
• Variables to be measured, sample sizes, sample containers,
preservatives, and sample holding times
• Equipment checklist
• Sample splits or performance samples to be submitted with the
samples
• Sample handling, packaging, labeling, and shipping require-
ments
• Laboratories to which samples will be shipped.
Tetra Tech (1987) provides QA/QC guidance for the following activities:
• Preparation for sampling program
• Sample collection
• Sample processing
• Sample size
E-43
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• Sample containers
• Sample preservation
• Sample holding times
• Sample shipping
• Recordkeeping
• Labeling
• Custody procedures
• Analytical methods
• Calibration and preventive maintenance
• Quality control checks
• Corrective action
• Data reporting requirements.
Field Sampling Procedures
For the field sampling effort, the following procedures are recommended:
• Establish and implement chain-of-custody protocols to track
samples from the point of collection to final disposition
• Establish and implement protocols to prepare sample containers
E-44
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• Prepare field "blank" samples to assess potential sample
contamination by the sampling devices
• Prepare "trip blanks" to assess potential contamination by
volatile organic analytes en route to the laboratory (1 trip
blank per sample shipment)
• Collect replicate samples to assess sample precision and the
homogeneity of samples collected
• Use appropriate sample collection procedures (see Table E-8).
Volatile organic samples and split composite samples should be
collected carefully. Grab samples for volatile organic analyses should be
collected in duplicate. Residual chlorine should be eliminated, and the
volatile sample containers should be filled with a minimum of mixing and to
capacity leaving no headspace. When splitting composite samples into
discrete aliquots for analyses, the composite sample should be mixed to
provide a homogeneous mixture. A representative portion of any solids in
the container should be suspended in the composite sample. Composite
samples may be homogenized by hand stirring with clean glass rods or by
mechanical stirring with teflon-coated paddles. Metal mixing devices should
not be used.
Laboratory Procedures
Laboratory analytical results must be accurate and reliable. Laboratory
QA/QC procedures are generally specified for each different analytical
method, and the level of QA/QC and associated deliverables vary among
methods (Tables E-5 to E-7). The following documentation is required by the
analytical laboratory for QA review of data on organic substances (see
Tables E-6 and E-7):
E-45
-------
• Initial multipoint calibration
• Demonstration of method proficiency
• Determination of method detection limit [usually 5-10 ppb for
base, neutral, and acid organic compounds (U.S. EPA Method
625); 0.005-0.10 ppb for pesticide/PCB analysis (U.S. EPA
Method 608); and 1-10 ppb for volatiles (U.S. EPA Method 624)]
• Daily checks of calibration and instrument tuning
• Daily analysis of method blanks (1 blank/20 samples)
• Analysis of duplicate samples (minimum of 5 percent of
samples analyzed) and conduct of matrix spikes to determine
organic recoveries.
The following documentation is required by the analytical laboratory for QA
review of data on inorganic substances (see Table E-5):
• Multipoint calibration
• Analysis of reagent blanks
• Matrix spikes of 0.5-5 times the sample concentration
• Determination of method detection limits
• Analysis of full method blanks at a minimum frequency of
every 20 samples, rather than reagent water blanks
• Verification of calibration by analysis of standards (daily or
with every 10 sample batches)
E-46
-------
• Performance of duplicate analyses for a minimum of 5 percent
of the total number of samples analyzed
• Use of the method of standard additions for samples demon-
strating interferences.
Data Evaluation
Data generated from the monitoring program should be evaluated using
the step-wise approach discussed below.
1. Assemble the original raw data reports and the associated QA/QC data.
The analytes and analytical methods used will determine the types of
QA/QC data generated, and may include the following:
• Sample results
• Blank sample results
• Instrument calibrations (initial and continuing)
• Matrix spike/matrix spike duplicate results
• Surrogate recovery data
• Instrument tuning data
• Chain-of-custody records
• Analytical request forms
• Gas chromatograms
• Mass spectra
E-47
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• Instrument detection limit determinations
• Serial dilution results
• Clean-water precision and accuracy studies
• Furnace atomic absorption quality control data
• Interference check data
• Laboratory control sample results
• Holding time documentation.
2. Because the resulting data will be used to determine regulatory
compliance of the discharge, the following sequence is recommended to
conduct a QA review of the data:
• Confirm the sample identifier, container, and preservation
with chain-of-custody records
• Confirm the analytical (e.g., extraction or digestion)
procedure used with the procedure requested
• Confirm that an acceptable instrument detection limit was
achieved
• Confirm that the analysis proceeded in the manner specified
• Confirm that all quality control data deliverables specified
by the analytical protocol have been submitted
• Confirm that the analysis was performed within the specified
sample holding time
E-48
-------
Confirm that the instrumentation used was properly calibrated
initially and that the method was validated
Confirm detection limits, precision, and accuracy for each
substance and review duplicate analysis results
Confirm that blank samples were analyzed and that the field
sampling and analytical procedures did not contaminate the
data
Evaluate the presence of matrix interferences through the use
of surrogate recoveries and matrix spikes
Annotate the data with appropriate qualifiers, and note
deviations from prescribed methods
Detail problems associated with the analyses.
E-49
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UPGRADING TO A FULL-SCALE SECONDARY TREATMENT FACILITY
Data obtained from the monitoring program described above will be used
to determine the mean and peak concentrations and site-specific toxic
pollutant removal capabilities for secondary treatment. Performance of the
secondary treatment pilot plant will be closely related to the attention and
expertise of the operator controlling the plant. If the pilot plant is not
properly operated, the data will not approximate the removals that could be
achieved with a full-scale facility. Conventional pollutant data (e.g.,
suspended solids, BOD) can be used to determine when the pilot plant is
operating within the expected design removal efficiencies. The most
important factor in performing site-specific toxic pollutant removal
investigations is to ensure that an acclimated biological seed exists prior
to initiating sample collection for pollutant analyses.
Plant operators should be aware that activated sludge microorganisms are
susceptible to biological and chemical effects that may kill the organisms
or severely inhibit their effectiveness. Accumulations of toxic waste
components (via gradual concentration from continuous discharges, or sudden
slugs) could limit the ability of the activated sludge system to achieve
design effluent quality (see Tables E-9 and E-10). Disruptions or changes
could be found by reviewing operating records (e.g., settling characteristics
of secondary sludge, species populations in the MLSS). If inhibition or
upset conditions are found, the concentration and source of each pollutant of
concern should be determined. Concentrations shown in Tables E-9 and E-10
are not absolute and should be used only for comparison purposes and
preliminary investigations.
Toxic pollutant removal efficiencies at the secondary treatment pilot
plant may be greater than those expected in a full-scale secondary treatment
facility. The pilot plant will be operated at a constant flow rate and will
not be subject to the diurnal and seasonal flow fluctuations normally
E-50
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TABLE E-9. REPORTED VALUES FOR ACTIVATED SLUDGE BIOLOGICAL
PROCESS TOLERANCE LIMITS OF ORGANIC PRIORITY POLLUTANTS
Threshold of
Pollutant Inhibitory Effect (mg/L)a
Acenaphthene NIb at 10
Acrolein NI at 62
Acrylonitrile NI at 152
Benzene 125
Benzidine 5
Carbon tetrachloride NI at 10
Chlorobenzene NI at 1
1,2,4-Trichlorobenzene NI at 6
Hexachlorobenzene 5
1,2-Dichloroethane NI at 258
1,1,1-Trichloroethane NI at 10
Hexachloroethane NI at 10
1,1-Dichloroethane NI at 10
1,1,2-Trichloroethane NI at 5
1,1,2,2-Tetrachloroethane NI at 201
Ms-(2-Chloroethyl) ether NI at 10
2-Chloroethyl vinyl ether NI at 10
2-Chloronaphthalene NI at 10
2,4,6-Trichlorophenol 50
para-Chloro-meta-cresol NI at 10
Chloroform NI at 10
2-Chlorophenol NI at 10
1,2-Dichlorobenzene 5
1,3-Dichlorobenzene 5
1,4-DiChlorobenzene 5
1,1-Dichloroethylene NI at 10
1,2-trans-Dichloroethylene NI at 10
2,4-Dichlorophenol NI at 75
1,2-Dichloropropane NI at 182
1,3-Dichloropropylene NI at 10
2,4-Dimethyl phenol NI at 10
2,4-Dinitrotoluene 5
2,6-Dinitrotoluene 5
1,2-Diphenylhydrazine 5
Ethyl benzene NI at 10
Fluoranthene NI at 5
E-51
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TABLE E-9. (Continued)
Threshold of
Pollutant Inhibitory Effect (mg/L)a
Ms-(2-Chloroisopropyl) ether NIb at 10
Chloromethane NI at 180
Bromoform NI at 10
Dichlorobromomethane NI at 10
Trichlorofluoromethane NI at 10
Chlorodibromomethane NI at 10
Hexachlorobutadiene NI at 10
Hexachlorocyclopentadiene NI at 10
Isophorone NI at 15.4
Naphthalene 500
Nitrobenzene 500
2-Nitrophenol NI at 10
4-Nitrophenol NI at 10
2,4-Dinitrophenol 1
N-Nitrosodiphenylamine NI at 10
N-Nitroso-di-N-propylamine . NI at 10
Pentachlorophenol 0.95
Phenol 200
Ms-(2-Ethyl Hexyl) phthalate NI at 10
Butyl Benzyl phthalate NI at 10
Di-n-butyl phthalate NI at 10
Di-n-octyl phthalate NI at 16.3
Diethyl phthalate NI at 10
Dimethyl phthalate NI at 10
Chrysane NI at 5
Acenaphthylene NI at 10
Anthracene 500
Fluorene NI at 10
Phenanthrene 500
Pyrene NI at 5
Tetrachloroethylene NI at 10
Toluene NI at 35
Trichloroethylene NI at 10
Aroclor-1242 NI at 1
Aroclor-1254 NI at 1
Aroclor-1221 NI at 1
Aroclor-1232 NI at 10
Aroclor-1016 NI at 1
a Unless otherwise indicated.
b NI = no inhibition at tested concentrations. No concentration is listed if
reference lacked concentration data.
Reference: U.S. EPA (1986c).
E-52
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TABLE E-10. REPORTED VALUES FOR ACTIVATED SLUDGE BIOLOGICAL
PROCESS TOLERANCE LIMITS OF INORGANIC PRIORITY POLLUTANTS
Threshold of
Pollutant Inhibitory Effect (mg/L)
Arsenic
Cadmi urn
Chromium (VI)
Chromium (III)
Copper
Cyanide
Lead
Mercury
Nickel
Silver
Zinc
0.1
1
1
10
1
0.1
0.1
0.1
1
5
0.03
Reference: U.S. EPA (1986c).
E-53
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experienced at treatment facilities, nor the slug loadings and batch
discharges which POTWs can experience in daily operation. In addition, at
the relatively higher aeration rates of the pilot plant system, higher
degrees of volatile organics stripping may occur, thereby implying higher
levels of removal of biodegradable material than might actually happen under
full-scale situations.
E-54
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DEMONSTRATING COMPLIANCE USING PILOT PLANT DATA
The purpose of operating a secondary treatment pilot plant is to
determine the concentrations of toxic substances in the effluent that would
be realized if the applicant were providing secondary treatment, rather than
less-than-secondary treatment as requested in the 301(h) application.
Effluent from the secondary treatment pilot plant is then analyzed to
determine the concentration of each toxic substance in the effluent. These
concentrations define the maximum allowable concentrations in the discharge
of less-than-secondary treated effluent.
To demonstrate secondary equivalency, the applicant must demonstrate
that the concentration of each toxic substance in the effluent of the
Section 301(h) modified discharge is equal to, or less than, the concen-
tration achieved using the secondary treatment pilot plant. For toxic
substances whose concentration in the Section 301(h) modified discharge
is greater than the concentration in the secondary treated effluent,
the applicant must lower the concentration using either or both of two
approaches. The first approach is to establish local limits for such
substances, in accordance with the guidance given above. The second
approach is to upgrade the treatment process within the POTW. Having
implemented either or both of these approaches, the applicant must then
provide results of additional effluent analyses to demonstrate that the
maximum allowable concentrations of toxic substances are not being exceeded
after the proposed controls have been implemented.
E-55
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REFERENCES
American Public Health Association/American Water Works Association/Water
Pollution Control Federation. 1985. Standard methods for the examination
of water and wastewater (16th ed). Port City Press, Baltimore, MD. 1268 pp.
Tetra Tech. 1982a. Design of 301(h) monitoring programs for municipal
wastewater discharges to marine waters. EPA 430/9-82-010. Prepared for
U.S. EPA, Office of Marine Discharge Evaluation, Washington DC. Tetra Tech,
Inc., Bellevue, WA. 135 pp.
Tetra Tech. 1982b. Revised Section 301(h) technical support document. EPA
430/9-82-011. Prepared for U.S. EPA, Office of Water, Washington, DC.
Tetra Tech, Inc., Bellevue, WA. 248 pp.
Tetra Tech. 1986a. Analytical methods for EPA priority pollutants and
301(h) pesticides in estuarine and marine sediments. Final Report. Prepared
for the Marine Operations Division, Office of Marine and Estuarine Protec-
tion, U.S. Environmental Protection Agency. EPA Contract No. 68-01-6938.
Tetra Tech, Inc. Bellevue, WA. 120 pp.
Tetra Tech. 1986b. Bi©accumulation monitoring guidance: 4. analytical
methods for U.S. EPA priority pollutants and 301(h) pesticides in tissues
from estuarine and marine organisms. Final Report. Prepared for the Marine
Operations Division, Office of Marine and Estuarine Protection, U.S.
Environmental Protection Agency. EPA Contract No. 68-01-6938. Tetra Tech,
Inc. Bellevue, WA. 118 pp.
Tetra Tech. 1987. Quality assurance/quality control (QA/QC) for 301(h)
monitoring programs: guidance on field and laboratory methods. EPA 430/9-
86-004. Prepared for U.S. EPA, Office of Marine and Estuarine Protection,
Washington, DC. Tetra Tech, Inc., Bellevue, WA. 277 pp.
U.S. Environmental Protection Agency. l?7?a» NPDES compliance sampling
manual. MCD-51. U.S. EPA, Enforcement Division, Office of Water Enforcement
Compliance Branch, Washington, DC. 138 pp.'
U.S. Environmental Protection Agency. 1979b (revised March 1983). Methods
for chemical analysis of water and wastes. EPA 600/4-79-020. U.S. EPA,
Environmental Monitoring and Support Laboratory, Cincinnati, OH.
U.S. Environmental Protection Agency. 1979c. Handbook for analytical
quality control in water and wastewater laboratories. U.S. EPA, National
Environmental Research Center, Cincinnati, OH.
U.S. Environmental Protection Agency. 1982c. Handbook for sampling and
sample preservation of water and wastewater. EPA 600/4-82-029. U.S. EPA,
Environmental Monitoring and Support Laboratory, Cincinnati, OH. 402 pp.
E-56
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U.S. Environmental Protection Agency. 1983a. Guidance manual for POTW
pretreatment program development. U.S. EPA, Office of Water Enforcement and
Permits, Washington, DC. 270 pp.
U.S. Environmental Protection Agency. 1983b. Procedures manual for
reviewing a POTW pretreatment program submission. U.S. EPA, Office of Water
Enforcement and Permits, Washington, DC. 125 pp.
U.S. Environmental Protection Agency. 1984a. NPDES compliance inspection
manual. U.S. EPA, Office of Water Enforcement and Permits, Washington, DC.
159 pp.
U.S. Environmental Protection Agency. 1984b. Report on the implementation
of Section 301(h). EPA 430/9-84-007. U.S. EPA, Office of Water Program
Operations. Washington, DC. 79 pp.
U.S. Environmental Protection Agency. 1985a. Guidance manual for implemen-
ting total toxic organics (TTO) pretreatment standards. U.S. EPA, Permits
Division, Washington, DC. 86 pp.
U.S. Environmental Protection Agency. 1985b. Guidance manual for the use of
production-based pretreatment standards and the combined wastestream
formula. U.S. EPA, Permits Division and Industrial Technology Division,
Washington, DC. 82 pp.
U.S. Environmental Protection Agency. 1986a. Pretreatment compliance
monitoring and enforcement guidance. U.S. EPA, Office of Water Enforcement
and Permits, Washington, DC. 135 pp.
U.S. Environmental Protection Agency. 1986b. Pretreatment compliance
inspection and audit manual for approval authorities. U.S. EPA, Office of
Water Enforcement and Permits, Washington, DC. 107 pp.
U.S. Environmental Protection Agency. 1986c. Report to Congress on the
discharge of hazardous wastes to publicly owned treatment works (the
domestic sawage study). EPA 530-SW-86-004. U.S. EPA, Office of Water
Regulations and Standards, Washington, DC. 450 pp.
U.S. Environmental Protection Agency. 1987a. Guidance manual for preventing
interference at POTWs. U.S. EPA, Office of Water Enforcement and Permits,
Washington, DC. 113 pp.
U.S. Environmental Protection Agency. 1987b. Guidance for reporting and
evaluating POTW noncompliance with pretreatment implementation requirements.
U.S. EPA, Office of Water Enforcement and Permits, Washington, DC. 23 pp.
U.S. Environmental Protection Agency. 1987c. Guidance manual on the
development and implementation of local discharge limitations under the
pretreatment program. U.S. EPA, Office of Water Enforcement and Permits,
Washington, DC. 355 pp.
E-57
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Water Pollution Control Federation. 1976. Manual of practice No. 11 - oper-
ation of wastewater treatment plants. Lancaster Press, Inc., Lancaster, PA.
pp. 117-160.
Water Pollution Control Federation. 1987. Manual of practice OM-9,
activated sludge. WPCF, Alexandria, VA, 182 pp.
Water Pollution Control Federation/American Society of Civil Engineers.
1977. Wastewater treatment plant design. Lancaster Press, Inc., Lancaster,
PA. pp. 217-282.
E-58
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ATTACHMENT 1 TO APPENDIX E
U.S. EPA OFFICE OF WATER ENFORCEMENT AND PERMITS
PROCEDURES FOR DEVELOPING TECHNICALLY BASED LOCAL LIMITS
E-59
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U.S. EPA OFFICE OF WATER ENFORCEMENT AND PERMITS PROCEDURES
FOR DEVELOPING TECHNICALLY BASED LOCAL LIMITS
INTRODUCTION
Publicly owned treatment works (POTWs) which discharge wastewater
into marine waters may be granted a waiver under Section 301(h) of the
Clean Water Act (CWA) from the requirement for secondary treatment [Sec-
tion 301(b)(l)(B)]. The Water Quality Act (WQA) of 1987 added a new
requirement, the urban area pretreatment program, to Section 301(h) of the
CWA for POTWs serving a population of 50,000 or more with respect to toxic
pollutants introduced by industrial dischargers. This provision now requires
each applicant to demonstrate that it has a pretreatment program in effect
for each toxic pollutant which, in combination with the applicant's own
treatment of discharges, removes the same amount of a given toxic pollutant
as would be removed if the applicant were to apply secondary treatment (as
defined in 40 CFR Part 133) and if it had no pretreatment program for the
toxic pollutant. This new "secondary removal equivalency" requirement
applies only with respect to a toxic pollutant introduced into a POTW by an
industrial discharger for which there is no "applicable pretreatment in
effect."
Under this new provision, for each toxic pollutant introduced by an
industrial user, the applicant must demonstrate either that there is an
applicable pretreatment requirement in effect or that it has a secondary
removal equivalency program for any toxic pollutant from industrial sources
for which there is no applicable pretreatment requirement. Applicable
pretreatment requirements may take the form of Federal categorical pretreat-
ment standards, local limits developed in accordance with 40 CFR Part 403,
or a combination thereof.
E-60
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POTWs must demonstrate that local limits developed are adequate and
enforceable. This new CWA provision also requires POTWs to demonstrate that
industrial sources are in compliance with all of their pretreatment
requirements, including numerical standards set by local limits, and that
those requirements will be enforced.
The following discussion provides a review of procedures for developing
technically-based local limits. Further details on the various approaches
are provided in U.S. EPA's Guidance Manual on the Development and Implemen-
tation of Local Discharge Limitations Under the Pretreatment Program
(December 1987). Questions about this guidance should be directed to the
U.S. EPA Regional Pretreatment Coordinators or to The Office of Water
Enforcement and Permits in Washington, DC.
OVERVIEW OF LOCAL LIMITS
Local discharge limitations are requirements developed by a POTW based
on local conditions and unique requirements at the POTW. These limits are
primarily intended to protect the treatment plant from industrial discharges
which could interfere with POTW treatment processes or pass through the
treatment plant to receiving waters and adversely impact water quality.
Local limits are also designed to prevent sludge contamination and protect
workers at the treatment plant.
Local limits are usually developed on a chemical specific basis and are
implemented as requirements that individual industrial dischargers must
meet. Once adopted, local limits are deemed to be Federal standards for the
purposes of the Clean Water Act Section 307(d) prohibition against violating
pretreatment standards [40 CFR 403.5(d) and 40 CFR 403.3(j)].
LOCAL LIMITS DEVELOPMENT APPROACHES
U.S. EPA's Guidance on the Development and Implementation of Local
Discharge Limitations Under the Pretreatment Program (1987) provides
various methods for calculating local limits. The predominant approach
E-61
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used by POTWs and advocated In the Guidance is a chemical specific approach
known as the maximum allowable headworks loading method. This method
involves back calculating from environmental and plant protection criteria
to a maximum allowable headworks loadings. This is accomplished pollutant
by pollutant for each environmental criteria or plant requirement and the
lowest or most limiting value for each pollutant serves as the basis for
allocation to industry and ultimate local limits. The steps of the maximum
allowable headworks loading local limits development process are shown in
Figure 1, and discussed below.
Maximum Allowable Headworks Loading Method
Determine Applicable Environmental Criteria—
The first step in developing local limits by the maximum allowable
headworks loading method is to determine applicable environmental criteria.
Environmental criteria generally include NPOES permit limits, water quality
standards or criteria, sludge disposal requirements, and unit process
inhibition values. The POTW should use all applicable environmental
criteria when developing local limits. Other appropriate requirements may
include worker health and safety criteria, collection system effects,
incinerator emission requirements or other applicable federal, state, or
local environmental protection requirements. Further information on how to
incorporate applicable environmental criteria into the local limits
development process is contained in the guidance manual.
Another less frequently used environmental criterion is biological
toxicity. POTWs that have conducted biological toxicity testing indicating
toxicity should develop local limits to correct the toxicity. Although
there is no method in the guidance manual to calculate maximum allowable
headworks loadings based on the results of toxicity testing, the manual
provides guidance and additional references on the Toxicity Reduction
Evaluation (TRE) process.
E-62
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Characterize Existing Loadings—
Industrial Users—During the local limits development process, the POTVI
must characterize existing loadings to the treatment plant. Local limits
should be based on site-specific monitoring data. This can be accomplished
by conducting monitoring of all industrial users. Either POTW monitoring
or self-monitoring data are acceptable, and information from the POTW's
industrial waste survey may also be of use.
Hauled Waste—If hauled wastes are accepted at the POTW, they may be a
significant source of toxic pollutant loadings. In such a case the POTW
should consider them as a significant nondomestic source in the determina-
tion of local limits.
Domestic Loadings—The POTW must also characterize domestic loadings.
Site-specific monitoring of a representative portion of the POTW's collection
system should form the basis for loadings from domestic/background sources.
Use of literature values must be justified by the POTW.
Treatment Plant Mom'torinq—The POTW must conduct sufficient monitoring
at the treatment plant to characterize influent, effluent, and sludge
loadings. Monitoring of the treatment plant influent, effluent, and sludge
should represent a minimum of 5 consecutive days. Preferably, monitoring
should include data for at least 1 day per month over at least 1 yr for
metals and other inorganic pollutants, and 1 day of sampling per year for
toxic pollutants [priority pollutants and Resource Conservation and Recovery
Act (RCRA) Appendix 9 constituents].
Determine Pollutants of Concern--
As one approach for achieving compliance with Section 301(h) regula-
tions, POTWs serving a population of 50,000 or more must demonstrate that
applicable pretreatment requirements are in effect for any and all toxic
pollutants contributed by an industrial user. Therefore, data should be
collected for any toxic pollutants of concern that could reasonably be
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expected to be discharged to the POTW in quantities that could pass through
or interfere with the POTW treatment process, contaminate the sludge, or
jeopardize worker health and safety or the collection system.
The POTW should perform at least one priority pollutant scan and one
RCRA Appendix 9 scan to identify potential pollutants of concern in the
influent, effluent, and sludge. The POTW must then address all toxic
pollutants (40 CFR 401.15) that are identified in any analysis above
detection limits by developing a local limit for each pollutant.
Calculate Maximum Headworks Loadings—
The POTW must calculate the maximum amount (Ib/day) of each toxic
pollutant contributed by an industrial user or received at the headworks of
the treatment plant that will allow the POTW to achieve all of the above
applicable environmental criteria. If the POTW does not calculate the
maximum allowable headworks loading to the POTW for each toxic pollutant, it
must provide justification why it has not done so. The nonconservative
pollutants (volatiles) require special consideration when conducting
headworks analysis (e.g., alternative formulas and allocation methods). All
calculations should be consistent with the approach outlined in the guidance
manual.
During this step of the local limits development process, the POTW
should demonstrate that an acceptable mass balance exists between the actual
loadings of pollutants at the headworks and the estimated loadings of
pollutants from specific source discharges. This mass balance can be
accomplished by calculating the actual loading of each pollutant from
influent monitoring data and comparing this value with the sum of the
estimated loadings from all individual sources (e.g., domestic, industrial,
hauled waste). The resulting calculated loadings from various sources
should be within 80 to 120 percent of the actual total influent loading and
flow.
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Calculate Allowable Industrial Loadings—
Once the POTW has calculated the maximum allowable headworks loading,
a safety factor must be applied and the value discounted for domestic/back-
ground loadings in order to determine the maximum allowable allocation
available for industrial users. A safety factor is incorporated into
the calculations to allow for future industrial growth and other dis-
crepancies that may enter into the calculations because of the use of
default data or variations in analytical procedures. The POTW should
provide justification for the selected safety factor, which will usually
range from 10 to 30 percent.
Allocate Allowable Industrial Loading-
After the POTW has calculated the allowable industrial loading, the
method chosen to allocate this loading depends on the number and types of
industrial users and the method of application (permits, contract, or sewer
use ordinance) employed by the POTW. Where the current loading of a
pollutant exceeds the maximum allowable headworks loading, the POTWs must
establish a local limit to reduce loadings to within the range of the
maximum allowable headworks loading. Where the current loading is far below
or approaches the maximum allowable headworks loading, the POTW must set
industrial discharge limits at current loadings to maintain the status quo.
The POTW should ensure that it has selected local limits that are
reasonable. All local limits should be at or above detection limits and
should not be so lenient as to provide industry additional opportunity to
pollute or encourage discharge of hazardous waste to the POTW.
Revise Local Limits-
Many variables on which these local limits calculations are based may
vary with time. Local limits must be revised on a periodic basis to reflect
changes in conditions or assumptions. Conditions which might require that
local limits be revised include but are not limited to changes in environ-
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mental criteria, availability of additional monitoring data, changes in
plant processes, and changes in POTW capacity or configuration.
Implement Local Limits—
Once local limits have been developed, they must be effectively
implemented. Local limits should be incorporated into the sewer use
ordinance or some form of individual control mechanisms.
OTHER LOCAL LIMITS APPROACHES
Other methods of local limits development have been used by POTWs.
They include the collection system approach, industrial user management
practice plans, and case-by-case discharge limits. These approaches are
briefly described below. U.S. EPA has published extensive guidance on the
development and implementation of local limits. Further information on each
of these methods and the maximum allowable headworks loading method can be
found in the Guidance Manual on the Development and Implementation of Local
Discharge Limitations Under the Pretreatment Program (U.S. EPA 1987).
Collection System Approach
To apply this method, the POTW identifies pollutants that may cause
fire and explosion hazards or other worker health and safety concerns.
Pollutants found to be present are evaluated for their propensity to
volatilize and are simplistically modeled to evaluate their expected
concentration in air. Comparisons are made with worker health exposure
criteria and lower explosive limits. Where values are of concern, the POTW
may set limits or require development of management practices to control
undesirable discharges. The collection system approach may also consider
the prohibition of pollutants with specific flashpoints to prevent discharge
of ignitable wastes.
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Industrial User Management Practice Plans
This approach consists of POTWs requiring industrial users to develop
management practices as enforceable pretreatment requirements for the
handling of chemicals and wastes. Examples of management practice plans
include chemical management practices, best management practices, and spill
prevention plans. Management practice plans are usually narrative local
limits.
Case-bv-Case Discharge Limits
In this approach a POTW sets numeric local limits based on best
professional judgment and on available technologies that are known to be
economically feasible. This approach is most often used when insufficient
data are available to employ the other methods noted above.
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ATTACHMENT 2 TO APPENDIX E
U.S. EPA GUIDANCE MANUAL ON THE DEVELOPMENT AND
IMPLEMENTATION OF LOCAL DISCHARGE LIMITATIONS
UNDER THE PRETREATMENT PROGRAM
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APPENDIX F
WATER QUALITY-BASED TOXICS CONTROL
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WATER QUALITY-BASED TOXICS CONTROL
Most applicants for Section 301(h) modified NPDES permits must
demonstrate satisfactorily to the U.S. EPA that discharge from the POTWs to
the marine or estuarine waters is in compliance with Section 301(h) of the
Clean Water Act (CWA). POTWs must enforce all applicable industrial
pretreatment requirements and demonstrate the effectiveness of both
industrial and nonindustrial source control programs. (Small dischargers,
with service area populations of less than 50,000 people and average dry
weather flows of less than 5.0 MGD, are exempt from effluent analysis and
industrial pretreatment requirements if they can certify that there are no
known or suspected sources of toxic pollutants or pesticides to the POTW.)
Section 301(h) industrial source control programs must be consistent with
pretreatment regulations and NPOES permit requirements. Under Sections 308
and 402 of the CWA, NPDES permit applicants [including 301(h) POTWs] are
required to collect effluent chemical (and possibly toxicity) data and
receiving water biological data to assure compliance with state water
quality standards. [If no state standards have been developed for specific
pollutants at the time of permit issuance, small and large dischargers must
then meet U.S. EPA's marine water quality criteria at the boundary of the
zone of initial dilution (ZID).]
In 1984, U.S. EPA (1984) recommended that whole-effluent toxicity
testing be used as a complement to chemical-specific analyses to assess
effluent discharges and determine NPDES permit limitations. [U.S. EPA
developed this approach because of certain disadvantages of the chemical-
specific techniques (i.e., the difficulty in identifying all potentially
toxic pollutants; the antagonistic, synergistic, or additive effects of
toxic pollutants; and the possibility of complex chemical interactions).]
The integrated approach is recommended to assure the attainment of water
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quality standards, to protect designated water uses, and to provide a tool
to control pollutants beyond the CWA technology-based requirements [e.g.,
Best Available Technology Economically Achievable (BAT)].
The Water Quality Act (WQA) of 1987 also emphasized the need for an
integrated approach of whole-effluent and chemical-specific analyses.
Congress required U.S. EPA to report on methods for establishing and
measuring water quality criteria for toxic pollutants through the use of
biological monitoring and assessment methods, and pollutant-specific
analyses. The WQA also signalled a shift in emphasis from discharge
requirements that were based primarily on technology-based pollution
controls to requirements that combined both technology-based and water
quality-based pollution controls.
In 1985, U.S. EPA's Office of Water Enforcement and Permits (OWEP) and
the Office of Water Regulations and Standards (OWRS) prepared the Technical
Support Document for Hater Quality-based Toxics Control (U.S. EPA 1985a).
Guidance was provided on the implementation of a bionionitoring policy for
the assessment and control of toxics using both the chemical-specific
approach and the whole-effluent toxicity approach. The chemical-specific
approach uses water quality criteria or state standards to limit specific
pollutants directly. The whole-effluent toxicity approach, as described in
the technical support document predominantly for non-marine waters, involves
the use of test organisms [e.g., Daphnia spp. (water flea), Pimephales
Promelas (fathead minnow)] that are exposed to serial dilutions of municipal
or industrial effluent/receiving water to measure acute (rapid response)
and/or chronic (long term response) toxicity. The document also provided
guidance for each step in the water-quality based toxics control program,
including the development of water quality standards and criteria, effluent
characterization, health hazard assessment, wasteload allocation, permit
requirements, and compliance monitoring.
In 1985, the U.S. EPA also issued a manual that established standardized
methods for measuring the acute toxicity of effluents to freshwater and
marine organisms (U.S. EPA 1985b) and the chronic toxicity of effluents to
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freshwater organisms (U.S. EPA 1985c). In 1988, U.S. EPA released a
document that established standardized methods for estimating the chronic
toxicity of effluents to marine and estuarine organisms (U.S. EPA 1988).
Chronic toxicity test methods were provided for five species: the sheepshead
minnow (Cyprinodon variegatus), the inland silverside (Menidia beryllina),
the mysid (Mysidopsis bahia), the sea urchin (Arbocia punctulata), and the
red macroalga (Champia parvula). However, because these tests use non-
indigenous species to estimate the chronic toxicity of effluents and
receiving waters to marine and estuarine organisms, test results may not
necessarily reflect actual field conditions within or near the ZID.
Moreover, test results may not accurately represent impacts of pollutant
discharges on balanced indigenous populations (BIPs).
•
U.S. EPA developed a permit writer's guide (U.S. EPA 1987) to assist
state and Federal NPDES permit writers in establishing water quality-based
permit limits for toxic pollutants. To meet these water quality-based
limits, the U.S. EPA is continuing to develop criteria that will assist
states in establishing their water quality standards and effluent permit
limitations. The U.S. EPA criteria under development include recommended
magnitudes, durations, and allowable frequencies of exceedance of pollutant
concentrations for both acute and chronic biological effects. POTW permit
limits on effluent toxicity could be imposed, and the NPDES permittee would
be required to conduct a toxicity reduction evaluation (TRE) and implement,
if necessary, a toxics control program (TCP) (U.S. EPA 1985a, 1987).
The TRE, a critical component of the TCP, must be conducted to identify
effluent toxicity sources, to determine (if possible) specific pollutants
responsible for the toxicity, and to identify source control options. The
TRE includes a review of the magnitude and extent of the toxicity problem,
the discharge characteristics, the receiving water characteristics, the need
for additional monitoring to determine water quality/toxicity effects, and
the other potential point and nonpoint toxicity sources in the POTW service
area.
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Because all NPDES-permitted discharges are unique, no single effluent
TRE procedure is applicable to every case. A TCP must be developed on an
individual case-by-case basis, and must include an evaluation of the impact
of 1) the existing POTW wastewater treatment process, 2) point and nonpoint
contributors to the POTW influent, 3) types of industries in the POTW
service area, 4) the variability, toxicity, and treatability of chemicals
in the effluent, and 5) the variability in species sensitivity based on
whole-effluent toxicity test results. Either technology-based or water
quality-based) source control options also need to be evaluated to determine
their effectiveness in reducing effluent toxicity and alleviating the water
quality violations.
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REFERENCES
U.S. Environmental Protection Agency. 1984. Development of water quality-
based permit limitations for toxic pollutants; national policy. U.S. EPA,
Washington, DC. Federal Register Vol. 49, No. 48. pp. 9016-9019.
U.S. Environmental Protection Agency. 1985a. Technical support document
for water quality-based toxics control. EPA 440/4-85-032. U.S. EPA Office
of Water, Washington, DC. 74 pp. + appendices.
U.S. Environmental Protection Agency. 1985b. Methods for measuring the
acute toxicity of effluents to freshwater and marine organisms. EPA 600/4-
85-013. U.S. EPA Environmental Monitoring and Support Laboratory, Cincin-
nati, OH.
U.S. Environmental Protection Agency. 1985c. Short-term methods for
estimating the chronic toxicity of effluents and receiving waters to
freshwater organisms. EPA 600/4-85-014. U.S. EPA Environmental Monitoring
and Support Laboratory, Cincinnati, OH.
U.S. Environmental Protection Agency. 1987. Permit writer's guide to
water quality-based permitting for toxic pollutants. EPA 440/4-87-005.
U.S. EPA Office of Water, Washington, DC.
U.S. Environmental Protection Agency. 1988. Short-term methods for
estimating the chronic toxicity of effluents and receiving waters to marine
and estuarine organisms. EPA 600/4-87-028. U.S. EPA Environmental
Monitoring and Support Laboratory, Cincinnati, OH.
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