Chapter
6
Water
Quality­
Based
Effluent
Limits
Permit
writers
must
consider
the
impact
of
every
proposed
surface
water
discharge
on
the
quality
of
the
receiving
water.
Water
quality
goals
for
a
water
body
are
defined
by
State
water
quality
standards.
A
permit
writer
may
find,
by
analyzing
the
effect
of
a
discharge
on
the
receiving
water,
that
technology­
based
permit
limits
are
not
sufficiently
stringent
to
meet
these
water
quality
standards.
In
such
cases,
the
CWA
and
EPA
regulations
require
development
of
more
stringent,
water
quality­
based
effluent
limits
(
WQBEL)
designed
to
ensure
that
water
quality
standards
are
met.
In
order
to
develop
effective
WQBELs,
permit
writers
must
be
familiar
with
State
water
quality
standards
methods
for
predicting
water
quality
impacts
from
discharges,
and
procedures
for
establishing
WQBELs.
This
chapter
provides
basic
information
on
these
subjects.
For
more
detailed
information
on
water
quality­
based
permitting,
refer
to
the
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control
(
TSD),
13
or
equivalent
State
or
regional
procedures.

13USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

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Chapter
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Water
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Effluent
Limits
6.1
Overview
of
Water
Quality
Standards
WQBELs
involve
a
site­
specific
evaluation
of
the
discharge
and
its
effect
on
the
receiving
water.
A
WQBEL
is
designed
to
protect
the
quality
of
the
receiving
water
by
ensuring
that
State
water
quality
standards
are
met.
To
understand
how
to
develop
WQBELs,
the
permit
writer
must
understand
State
water
quality
standards
and
the
water
quality
goals
they
define.

Section
303(
c)
of
the
CWA
requires
every
State
to
develop
water
quality
standards
applicable
to
all
water
bodies
or
segments
of
water
bodies
that
lie
within
the
State.
Once
standards
are
developed,
EPA
must
approve
or
disapprove
them.
Water
quality
standards
should
(
1)
include
provisions
for
restoring
and
maintaining
the
chemical,
physical,
and
biological
integrity
of
State
waters,
(
2)
provide,
wherever
attainable,
water
quality
for
the
protection
and
propagation
of
fish,
shellfish,
and
wildlife
and
recreation
in
and
on
the
water
("
fishable/
swimmable"),
and
(
3)
consider
the
use
and
value
of
State
waters
for
public
water
supplies,
propagation
of
fish
and
wildlife,
recreation,
agriculture
and
industrial
purposes,
and
navigation.
Currently,

States
are
required
to
review
their
water
quality
standards
at
least
once
every
three
years
and
revise
them
as
necessary.
When
writing
a
permit,
the
permit
writer
must
use
the
most
current
State
water
quality
standards.
For
more
information
regarding
procedures
for
developing
water
quality
standards,
refer
to
EPA's
Water
Quality
Standards
Regulation
at
40
CFR
Part
131
and
the
Water
Quality
Standards
Handbook:
Second
Edition.
14
Under
§
510
of
the
CWA,
States
may
develop
water
quality
standards
more
stringent
than
required
by
the
Water
Quality
Standards
Regulation.
Also,
EPA
reviews
and
approves
or
disapproves
State­
adopted
water
quality
standards.
EPA's
review
is
to
ensure
that
the
State
water
quality
standards
meet
the
requirements
of
the
CWA
and
the
Water
Quality
Standards
Regulation.
EPA
may
promulgate
a
new
or
revised
standard
for
a
State
where
necessary
to
meet
the
requirements
of
the
CWA.

14USEPA
(
1994).
Water
Quality
Standards
Handbook:
Second
Edition.
EPA
823­
B­
94­
005a.
Office
of
Water.

88
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Writers'
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Water
Quality­
Based
Effluent
Limits
Chapter
6
6.1.1
Components
of
Water
Quality
Standards
Water
quality
standards
are
composed
of
three
parts:

°
Use
classifications
°
Numeric
and/
or
narrative
water
quality
criteria
°
Antidegradation
policy.

Each
of
these
three
components
is
described
below.

Use
Classification
The
first
part
of
a
State's
water
quality
standard
is
a
classification
system
for
water
bodies
based
on
the
expected
beneficial
uses
of
those
water
bodies.
The
CWA
describes
various
uses
of
waters
that
are
considered
desirable
and
should
be
protected.
These
uses
include
public
water
supply,
recreation,
and
propagation
of
fish
and
wildlife.
The
States
are
free
to
designate
more
specific
uses
(
e.
g.,
cold
water
aquatic
life,
agricultural),
or
to
designate
uses
not
mentioned
in
the
CWA,
with
the
exception
of
waste
transport
and
assimilation
which
is
not
an
acceptable
designated
use
(
see
40
CFR
§
131.10(
a)).
Designated
uses
should
support
the
"
fishable/

swimmable"
goal
of
Section
101(
a)(
2)
of
the
CWA
where
such
uses
are
attainable.
A
State
must
perform
a
use
attainability
analysis
under
40
CFR
§
131.10(
j)
where
it:
(
1)

does
not
designate
a
"
fishable/
swimmable"
use
for
a
water;
(
2)
wishes
to
remove
a
"
fishable/
swimmable"
designated
use;
or
(
3)
wishes
to
adopt
subcategories
of
a
designated
"
fishable/
swimmable"
use
that
would
require
less
stringent
criteria.
The
use
attainability
analysis
is
a
structured
scientific
assessment
of
the
factors
affecting
the
attainment
of
a
use.
The
analysis
may
include
physical,
chemical,
biological,
and
economic
factors
as
described
in
40
CFR
§
131.10(
g).

Water
Quality
Criteria
The
second
part
of
a
State's
water
quality
standard
is
the
water
quality
criteria
deemed
necessary
to
support
the
designated
uses
of
each
water
body.
Section
303(
a­
c)
of
the
CWA
requires
States
to
adopt
criteria
sufficient
to
protect
designated
uses
for
State
waters.
These
criteria
may
be
numeric
or
narrative.
The
CWA
requires
States
to
adopt
numeric
criteria
for
certain
toxic
pollutants
where
they
are
necessary
to
protect
designated
uses.
EPA's
Water
Quality
Standards
Regulation
encourages
NPDES
Permit
Writers'
Manual
­
89
Chapter
6
Water
Quality­
Based
Effluent
Limits
States
to
adopt
both
numeric
and
narrative
water
quality
criteria.
See
Section
6.1.2,

Establishing
Water
Quality
Criteria,
of
this
manual
for
additional
information
on
the
development
of
numeric
and
narrative
criteria.

Antidegradation
Policy
The
third
part
of
a
State's
water
quality
standard
is
the
State's
antidegradation
policy.
Each
State
is
required
to
adopt
an
antidegradation
policy
consistent
with
EPA's
antidegradation
regulations
(
40
CFR
§
131.12)
and
to
identify
the
methods
it
will
use
for
implementing
the
policy.
Antidegradation
policies
provide
three
tiers
of
protection
from
degradation
of
water
quality:

°
Tier
1
 
Protects
existing
uses
and
provides
the
absolute
floor
of
water
quality
for
all
waters
of
the
United
States.
Existing
instream
water
uses
are
those
uses
that
were
attained
on
or
after
November
28,
1975,
the
date
of
EPA's
first
Water
Quality
Standards
Regulation,
or
uses
for
which
existing
water
quality
is
suitable
unless
prevented
by
physical
problems
such
as
substrate
or
flow.

°
Tier
2
 
Protects
the
level
of
water
quality
necessary
to
support
propagation
of
fish,
shellfish,
and
wildlife
and
recreation
in
and
on
the
water
in
waters
that
are
currently
of
higher
quality
than
required
to
support
these
uses.
Before
water
quality
in
Tier
2
waters
can
be
lowered,
there
must
be
an
antidegradation
review
consisting
of:
(
1)
a
finding
that
it
is
necessary
to
accommodate
important
economical
or
social
development
in
the
area
where
the
waters
are
located;
(
2)
full
satisfaction
of
all
intergovernmental
coordination
and
public
participation
provisions;
and
(
3)
assurance
that
the
highest
statutory
and
regulatory
requirements
for
point
sources
and
best
management
practices
for
nonpoint
sources
are
achieved.
Furthermore,
water
quality
may
not
be
lowered
to
less
than
the
level
necessary
to
fully
protect
the
"
fishable/
swimmable"
uses
and
other
existing
uses.

°
Tier
3
 
Protects
the
quality
of
outstanding
national
resources,
such
as
waters
of
national
and
State
parks
and
wildlife
refuges
and
waters
of
exceptional
recreational
or
ecological
significance.
There
may
be
no
new
or
increased
discharges
to
these
waters
and
no
new
or
increased
discharges
to
tributaries
of
these
waters
that
would
result
in
lower
water
quality
(
with
the
exception
of
some
limited
activities
that
result
in
temporary
and
short­
term
changes
in
water
quality).

90
­
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Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
Additional
information
on
water
quality
standards
is
available
in
the
Water
Quality
Standards
Handbook:
Second
Edition.
15
6.1.2
Establishing
Water
Quality
Criteria
Water
quality
criteria
set
ambient
levels
of
individual
pollutants
or
parameters,

or
describe
conditions
of
a
water
body
that,
if
met,
will
generally
protect
the
designated
use
of
the
water.
Water
quality
criteria
are
developed
to
protect
aquatic
life
and
human
health,
and,
in
some
cases,
wildlife
from
the
deleterious
effects
of
pollutants.
Section
304(
a)
of
the
CWA
directs
EPA
to
publish
water
quality
criteria
guidance
to
assist
States
in
developing
water
quality
standards.
EPA
criteria
or
guidance
consists
of
three
components:

°
Magnitude
 
The
level
of
pollutant
(
or
pollutant
parameter),
generally
expressed
as
a
concentration,
that
is
allowable.

°
Duration
 
The
period
of
time
(
averaging
period)
over
which
the
instream
concentration
is
averaged
for
comparison
with
criteria
concentrations.

°
Frequency
 
How
often
criteria
can
be
exceeded.

EPA's
efforts
on
criteria
development
have
been
focused
on
the
65
pollutants
listed
in
Section
307(
a)
of
the
CWA.
Some
of
the
65
pollutants
on
the
list
are
actually
families
or
classes
of
organic
compounds
consisting
of
many
individual
chemicals.

EPA
translated
this
list
into
a
new
list
of
129
priority
toxic
pollutants.
Subsequently,

two
volatile
chemicals
and
one
water
unstable
chemical
were
removed
from
the
list
so
that
the
present
list
contains
126
priority
toxic
pollutants.
Criteria
for
the
priority
toxic
pollutants
that
EPA
has
developed
to
date
are
contained
in
individual
criteria
documents
and
summarized
in
a
document
entitled
Quality
Criteria
for
Water
1986,
16
more
commonly
referred
to
as
the
Gold
Book.

15USEPA
(
1994).
Water
Quality
Standards
Handbook:
Second
Edition.
EPA
823­
B­
94­
005a.
Office
of
Water.

16USEPA
(
1986).
Quality
Criteria
for
Water,
1986.
EPA­
440/
5­
86­
001.
Office
of
Water
Regulations
and
Standards.

NPDES
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Writers'
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Chapter
6
Water
Quality­
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Effluent
Limits
Numeric
Criteria
Numeric
water
quality
criteria
are
values
expressed
as
levels,
constituent
concentrations,
toxicity
units
(
see
discussion
of
whole
effluent
toxicity
below),
or
numbers
deemed
necessary
to
protect
designated
uses.
These
criteria
often
form
the
basis
for
NPDES
WQBELs.
They
also
can
be
useful
in
assessing
and
managing
nonpoint
sources.
In
1987,
Congress
increased
the
emphasis
of
the
CWA
on
numeric
criteria
for
toxic
pollutants
by
enacting
Section
303(
c)(
2)(
B)
of
the
act.
This
section
requires
States
to
adopt
numeric
criteria
for
the
126
priority
toxic
pollutants
for
which
EPA
has
developed
criteria
guidance
and
where
the
discharge
or
presence
of
the
pollutant
could
reasonably
be
expected
to
interfere
with
the
designated
uses
of
a
water
body.
States
may
establish
numeric
criteria
using
EPA
criteria
guidance,

modified
to
reflect
site
specific
conditions,
or
other
scientifically
defensible
methods.

EPA
criteria
for
the
protection
of
aquatic
life
address
both
short­
term
(
acute)

and
long­
term
(
chronic)
effects
on
both
freshwater
and
saltwater
species.
The
following
example
shows
the
current
EPA
criteria
for
cadmium.

Example:

Aquatic
Life
The
procedures
described
in
the
Guidelines
for
Deriving
Numerical
National
Water
Quality
Criteria
for
the
Protection
of
Aquatic
Organisms
and
Their
Uses
indicate
that,
except
possibly
where
a
locally
important
species
is
very
sensitive,
freshwater
aquatic
organisms
and
their
uses
should
not
be
affected
unacceptably
if
the
4­
day
average
concentration
(
in
ug/
L)
of
cadmium
does
not
exceed
the
numerical
value
given
by
e(
0.7852[
1n(
hardness)]
 
3.490)
more
than
once
every
3
years
on
the
average
and
if
the
one­
hour
average
concentration
(
in
ug/
L)
does
not
exceed
the
numerical
value
given
by
e(
1.128[
1n(
hardness)]
 
3.828)
more
than
once
every
3
years
on
the
average.
For
example,
at
hardnesses
of
50,
100,
and
200
mg/
L
as
CaCO
3
the
4­
day
average
concentrations
of
cadmium
are
0.66,
1.1,
and
2.0
ug/
L,
respectively,
and
the
1­
hour
average
concentrations
are
1.8,
3.9
and
8.6
ug/
L.
If
brook
trout,
brown
trout,
and
striped
bass
are
as
sensitive
as
some
data
indicate,
they
might
not
be
protected
by
this
criterion.

Human
health
criteria
are
designed
to
protect
people
from
exposure
resulting
from
consumption
of
water
and
fish
or
other
aquatic
life
(
e.
g.,
mussels,
crayfish).
The
following
example
contains
EPA's
human
health
criteria
for
cadmium.

92
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Narrative
Criteria
Example:

Human
Health
The
ambient
water
quality
criterion
for
cadmium
is
recommended
to
be
identical
to
the
existing
drinking
water
standard
which
is
10
ug/
L.
Analysis
of
the
toxic
effects
data
resulted
in
a
calculated
level
which
is
protective
of
human
health
against
the
ingestion
of
contaminated
water
and
contaminated
aquatic
organisms.
The
calculated
value
is
comparable
to
the
present
standard.
For
this
reason
a
selective
criterion
based
on
exposure
solely
from
consumption
of
6.5
grams
of
aquatic
organisms
was
not
derived.

All
States
have
adopted
narrative
criteria
to
supplement
numeric
criteria
for
toxicants.
Narrative
criteria
are
statements
that
describe
the
desired
water
quality
goal.
Examples
of
narrative
criteria
are
provided
below.
Narrative
criteria
can
be
the
basis
for
limiting
specific
pollutants
where
the
State
has
no
numeric
criteria
for
those
pollutants
or
they
can
be
used
to
limit
toxicity
where
the
toxicity
cannot
be
traced
to
a
specific
pollutant.
EPA's
Water
Quality
Standards
Regulation
requires
States
to
develop
implementation
procedures
for
narrative
criteria
that
address
all
mechanisms
to
be
used
by
the
State
to
ensure
that
narrative
criteria
are
attained.

Example:

Narrative
criteria
can
be
statements,
requiring
that
discharges
be
"
free
from
toxics
in
toxic
amounts"
or
"
free
of
objectionable
color,
odor,
taste,
and
turbidity."

6.1.3
Future
Directions
for
Water
Quality
Standards
The
water
quality
standards
program
is
constantly
evolving.
New
scientific,

regulatory,
and
policy
developments
affect
the
nature
of
the
program.
For
example,

three
new
areas
where
criteria
are
being
developed
include
biological,
sediment,
and
wildlife
criteria.

°
Biological
Criteria
 
EPA
is
developing
numerical
values
or
narrative
expressions
that
describe
the
reference
biological
integrity
of
aquatic
communities
inhabiting
unimpaired
waters
of
a
designated
aquatic
life
use.
The
biological
communities
in
these
waters
represent
the
best
attainable
condition
for
the
organisms.
According
to
EPA
policy,
States
should
develop
and
implement
biological
criteria
in
their
water
quality
standards.

°
Sediment
Criteria
 
Sediment
contamination
can
result
from
the
deposition
of
toxicants
over
long
periods
of
time
and
is
also
responsible
for
water
NPDES
Permit
Writers'
Manual
­
93
Chapter
6
Water
Quality­
Based
Effluent
Limits
quality
impacts
when
these
toxicants
are
released
back
into
the
water
column.
EPA
has
proposed
sediment
criteria
for
five
organic
chemicals
(
phenanthrene,
fluoranthene,
dieldrin,
acenaphthene,
and
endrin)
(
59
FR
2652;
1/
18/
94).
EPA
also
is
developing
sediment
criteria
for
metals,
and
has
begun
development
of
implementation
guidance
for
sediment
criteria.

°
Wildlife
Criteria
 
EPA
is
undertaking
an
initiative
to
develop
numeric
wildlife
criteria
to
establish
ambient
concentrations
of
certain
chemicals
to
protect
mammals
and
birds
from
adverse
impacts
due
to
consumption
of
food
and/
or
water
containing
those
chemicals.

6.2
Approaches
to
Implementing
Water
Quality
Standards
The
control
of
toxic
discharges
to
waters
of
the
United
States
in
an
important
objective
of
the
CWA.
To
effectively
accomplish
this
objective,
EPA
recommends
an
integrated
approach
to
implementing
water
quality
standards
and
developing
WQBELs.

This
integrated
approach
includes
three
elements:
a
chemical­
specific
approach,
a
whole
effluent
toxicity
(
WET)
approach,
and
a
biological
criteria
or
bioassessment
approach.
Each
of
the
three
approaches
is
briefly
described
below.
Exhibit
6­
1
summarizes
the
capabilities
and
limitations
of
each
approach.

6.2.1
Chemical­
Specific
Approach
The
chemical­
specific
approach
uses
the
chemical­
specific
criteria
for
protection
of
aquatic
life,
human
health,
and
wildlife
adopted
into
a
State's
water
quality
standards.
The
criteria
are
used
as
the
basis
to
analyze
an
effluent,
decide
which
chemicals
need
controls,
and
derive
permit
limits
that
will
control
those
chemicals
to
the
extent
necessary
to
achieve
water
quality
standards
in
the
receiving
water.

Chemical­
specific
WQBELs
in
NPDES
permits
involve
a
site­
specific
evaluation
of
the
discharge
and
its
effect
upon
the
receiving
water.
This
approach
allows
for
the
control
of
individual
chemicals
before
a
water
quality
impact
has
occurred
or
to
assist
in
returning
water
quality
to
a
level
that
will
meet
designated
uses.

6.2.2
Whole
Effluent
Toxicity
(
WET)
Approach
WET,
the
second
approach
to
water
quality­
based
toxics
control,
protects
the
receiving
water
quality
from
the
aggregate
toxic
effect
of
a
mixture
of
pollutants
in
the
effluent.
WET
tests
measure
the
degree
of
response
of
exposed
aquatic
test
organisms
to
an
effluent.
The
WET
approach
is
useful
for
complex
effluents
where
it
94
­
NPDES
Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
may
be
infeasible
to
identify
and
regulate
all
toxic
pollutants
in
the
discharge
or
where
EXHIBIT
6­
1
Components
of
an
Integrated
Approach
to
Water
Quality­
Based
Toxics
Control
Control
Approach
Capabilities
Limitations
Chemical­
Specific
 
Human
health
protection
 
Complete
toxicology
 
Straightforward
treatability
 
Fate
understood
 
Less
expensive
testing
if
only
a
few
toxicants
are
present
 
Prevents
impacts
 
Does
not
consider
all
toxics
present
 
Bioavailability
not
measured
 
Interactions
of
mixtures
(
e.
g.,
additivity)
unaccounted
for
 
Complete
testing
can
be
expensive
 
Direct
biological
impairment
not
measured
Whole
effluent
toxicity
 
Aggregate
toxicity
 
Unknown
toxicants
addressed
 
Bioavailability
measured
 
Accurate
toxicology
 
Prevents
impacts
 
No
direct
human
health
protection
 
Incomplete
toxicology
(
few
species
may
be
tested)
 
No
direct
treatment
 
No
persistency
or
sediment
coverage
 
Conditions
in
ambient
may
be
different
 
Incomplete
knowledge
of
causative
toxicant
Bioassessments
 
Measures
actual
receiving
water
effects
 
Historical
trend
analysis
 
Assesses
quality
above
standards
 
Total
effect
of
all
sources,
including
unknown
sources
 
Critical
flow
effects
not
always
assessed
 
Difficult
to
interpret
impacts
 
Cause
of
impact
not
identified
 
No
differentiation
of
sources
 
Impact
has
already
occurred
 
No
direct
human
health
protection
chemical­
specific
pollutant
limits
are
set,
but
synergistic
effects
are
suspected
to
be
problematic.
The
WET
approach
allows
the
permit
writer
to
be
protective
of
the
narrative
"
no
toxics
in
toxic
amounts"
criterion
that
is
applicable
to
all
waters
of
the
United
States
and
implement
numeric
criteria
for
toxicity
(
see
the
discussion
below
on
acute
and
chronic
toxicity).

There
are
two
types
of
WET
tests:
acute
and
chronic.
An
acute
toxicity
test
is
usually
conducted
over
a
short
time
period
(
e.
g.,
48
hours)
and
the
endpoint
measured
is
mortality.
The
endpoint
for
an
acute
test
is
often
expressed
as
an
LC50
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Permit
Writers'
Manual
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Chapter
6
Water
Quality­
Based
Effluent
Limits
(
i.
e.,
the
concentration
of
effluent
that
is
lethal
to
50
percent
of
the
exposed
test
organisms).
A
chronic
toxicity
test
is
usually
conducted
over
a
longer
period
of
time
(
e.
g.,
7
days)
and
the
endpoint
measured
is
mortality
and
sublethal
effects,
such
as
changes
in
reproduction
and
growth.
The
endpoint
is
often
expressed
as
the
no
observed
effect
concentration
(
NOEC),
the
lowest
observed
effect
concentration
(
LOEC),
or
the
inhibition
concentration
(
IC).
The
NOEC
is
the
highest
concentration
of
effluent
at
which
no
adverse
effects
are
observed
on
the
aquatic
test
organisms.
The
LOEC
is
the
lowest
concentration
of
effluent
that
causes
observable
adverse
effects
in
exposed
test
organisms.
The
IC
is
an
estimate
of
the
effluent
concentration
that
would
cause
a
given
percent
reduction
in
a
biological
measurement
of
the
test
organisms.

To
express
criteria,
facilitate
modeling,
and
express
permit
limits,
EPA
recommends
that
toxicity
be
expressed
in
terms
of
"
toxic
units."
A
toxic
unit
(
TU)
is
merely
the
inverse
of
the
sample
fraction.
Toxicity,
expressed
as
percent
sample,
is
divided
into
100
to
obtain
toxic
units.

Example:

If
a
chronic
test
result
is
a
NOEC
of
25
percent
effluent,
that
result
can
be
expressed
as
100/
25
or
4.0
chronic
toxic
units
(
4.0
TUc);

If
an
acute
test
result
is
a
LC
50
of
60
percent,
that
result
can
also
be
expressed
as
100/
60
or
1.7
acute
toxic
units
(
1.7
TUa).

It
is
important
to
distinguish
acute
toxic
units
(
TUa)
from
chronic
toxic
units
(
TUc).
The
difference
between
TUa
and
TUc
can
be
likened
to
the
difference
between
miles
and
kilometers.
Thus,
to
compare
a
TUa
and
a
TUc,
a
conversion
factor
called
an
acute­
to­
chronic
ratio
(
ACR),
must
be
developed.
The
ACR
is
a
conversion
factor
that
changes
TUa
into
equivalent
TUc.
If
data
are
insufficient
to
calculate
an
ACR
(
i.
e.,
less
than
10
sets
of
WET
data),
EPA
recommends
a
default
value
of
ACR=
10.
Where
sufficient
data
are
available,
the
ACR
should
be
calculated
as
the
mean
of
the
individual
ACRs
for
each
pair
of
acute
and
chronic
WET
test
data.

The
following
examples
show:
(
1)
how
the
ACR
converts
TUa
into
TUc;
(
2)
how
to
calculate
an
ACR
from
existing
data;
and
(
3)
how
the
ACR
allows
permit
writers
to
compare
TUa
and
TUc.

96
­
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Manual
Water
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Based
Effluent
Limits
Chapter
6
Acute
to
Chronic
Ratio
Formulas:

°
By
definition:

°
Thus:

°
Substituting:

Example
1:

Given:
LC
50
=
28%

NOEC
=
10%

Example
2:

Given:
TUc
=
10.0
TUa
=
3.6
Example:

Toxicity
data
from
POTW
Discharge
Monitoring
Reports
(
C.
dubia):

LC
50
(%
Effluent)
NOEC
(%
Effluent)
Acute
to
Chronic
Ratio*
(
ACR)
62
10
6.2
18
10
1.8
68
25
2.7
61
10
6.1
63
25
2.5
70
25
2.8
17
5
3.4
35
10
3.5
35
10
3.5
35
25
1.4
47
10
4.7
Mean
46
15
3.5
*
Calculated
value.

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Chapter
6
Water
Quality­
Based
Effluent
Limits
Example:

Where:
Wasteload
Allocation
(
WLA)
=
toxicity
level
in
discharge
that
will
meet
state
water
quality
criteria
(
calculated
value)
Acute
WLA
=
1.5
TUa
Chronic
WLA
=
4.9
TUc
Because
TUc
and
TUa
are
in
different
units,
we
can
use
the
ACR
to
convert
TUa
to
TUc
assuming
an
ACR
=
10
(
default
value).

TUa
x
ACR
=
TUa,
c
[
where
"
TUa,
c"
=
acute
toxicity
expressed
in
chronic
toxicity
units]
1.5
TUa
x
10
=
15
TUa,
c
4.9
TUc
<
15
TUa,
c:
therefore
the
chronic
WLA
(
4.9
TUc)
is
more
stringent
than
the
acute
WLA
(
1.5
TUa);
thus
4.9
TUc
is
used
to
develop
the
permit
limit.

The
ACR
allows
us
to
directly
compare
the
chronic
WLA
of
4.9
TUc
with
the
acute
WLA
of
1.5
TUa.
Using
the
ACR
of
10,
we
can
express
1.5
TUa
in
chronic
toxicity
units
as
15
TUa,
c.
We
see
that
4.9
TUc
is
less
than
15
TUa,
c,
(
the
acute
WLA
expressed
in
chronic
toxicity
units).
The
more
stringent
value
should
be
used
for
developing
permit
limits.
Thus,
the
appropriate
requirement
that
would
meet
both
acute
and
chronic
criteria
for
toxicity
is
4.9
TUc.

6.2.3
Biological
Criteria
or
Biological
Assessment
Approach
The
biological
criteria
or
biological
assessment
approach
is
the
third
approach
to
water
quality­
based
toxics
control.
This
approach
is
used
to
assess
the
overall
biological
integrity
of
an
aquatic
community.
Biological
criteria,
or
"
biocriteria,"
are
numerical
values
or
narrative
statements
that
describe
the
reference
biological
integrity
of
aquatic
communities
inhabiting
waters
of
a
given
designated
aquatic
life
use.
When
incorporated
into
State
water
quality
standards,
biological
criteria
and
aquatic
life
use
designations
serve
as
direct,
legal
endpoints
for
determining
aquatic
life
use
attainment.
Once
biocriteria
are
developed,
the
biological
condition
of
a
water
body
may
be
assessed
through
a
biological
assessment,
or
"
bioassessment."
A
bioassessment
is
an
evaluation
of
the
biological
condition
of
a
waterbody
using
biological
surveys
and
other
direct
measurements
of
resident
biota
in
surface
waters.

A
biological
survey,
or
"
biosurvey,"
consists
of
collecting,
processing,
and
analyzing
representative
portions
of
a
resident
aquatic
community
to
determine
the
community
structure
and
function.
The
results
of
biosurveys
may
be
compared
to
the
reference
water
body
to
determine
if
the
biocriteria
for
the
designated
use
of
the
water
body
are
98
­
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Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
being
met.
EPA
issued
guidance
on
this
approach
in
Biological
Criteria:
National
Program
Guidance
for
Surface
Waters.
17
To
be
fully
protective
of
water
quality,
EPA
developed
the
concept
of
"
independent
application"
to
characterize
the
relationship
of
the
three
approaches
to
implementing
water
quality
standards.
Independent
application
says
that
the
results
of
one
approach
should
not
be
used
to
contradict
or
overrule
the
results
of
the
others.

Independent
application
recognizes
that
each
approach
has
unique
as
well
as
overlapping
attributes,
sensitivities,
and
program
applications;
thus,
no
single
approach
for
detecting
impact
should
be
considered
uniformly
superior
to
any
other
approach.

For
example,
the
inability
to
detect
receiving
water
impacts
using
a
biosurvey
alone
is
insufficient
evidence
to
waive
or
relax
a
permit
limit
established
using
either
the
chemical­
specific
or
WET
method.

6.3
Determining
the
Need
for
WQBELs
Once
the
applicable
designated
uses
and
water
quality
criteria
for
a
water
body
are
determined,
the
permit
writer
must
ensure
that
dischargers
do
not
cause
exceedences
of
these
criteria.
If,
after
technology­
based
limits
are
applied,
the
permit
writer
projects
that
a
point
source
discharger
may
exceed
an
applicable
criterion,
a
WQBEL
must
be
imposed.
EPA
regulations
at
40
CFR
§
122.44(
d)
require
that
all
effluents
be
characterized
by
the
permitting
authority
to
determine
the
need
for
WQBELs
in
the
permit.

6.3.1
Defining
"
Reasonable
Potential"
to
Exceed
Applicable
Criteria
In
deciding
whether
or
not
WQBELs
are
needed
to
protect
water
quality,
a
permit
writer
must
determine
whether
the
discharge
causes,
has
the
reasonable
potential
to
cause,
or
contributes
to
an
excursion
of
numeric
or
narrative
water
quality
criteria.
EPA's
regulation
at
40
CFR
§
122.44(
d)(
1)
establishes
the
basis
for
determining
if
there
is
an
excursion
of
the
numeric
or
narrative
water
quality
criteria.

At
a
minimum,
the
permit
writer
must
make
this
determination
at
each
permit
reissuance
and
must
develop
WQBELs
as
necessary
to
control
the
discharge
of
pollutants.

17USEPA
(
1990).
Biological
Criteria:
National
Program
Guidance
for
Surface
Waters.
EPA­
440/
5­
91­
004.
Office
of
Science
and
Technology.

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Chapter
6
Water
Quality­
Based
Effluent
Limits
Reasonable
Potential
and
Numeric
Criteria
When
conducting
an
effluent
characterization
to
determine
if
WQBELs
are
needed
based
on
chemical­
specific
numeric
criteria
in
the
water
quality
standards,
the
permit
writer
projects
the
receiving
water
concentration
of
pollutants
contained
in
the
effluent
once
that
effluent
enters
the
receiving
water.
If
the
projected
concentration
exceeds
the
applicable
numeric
water
quality
criterion
for
a
specific
pollutant,
there
is
reasonable
potential
that
the
discharge
may
cause
or
contribute
to
an
excursion
above
the
applicable
water
quality
standards
and
the
permit
writer
must
develop
a
WQBEL.

If
a
State
has
numeric
criteria
for
WET,
the
permit
writer
projects
the
toxicity
once
the
effluent
enters
the
receiving
water.
The
permit
writer
then
compares
the
toxicity
of
the
receiving
water
to
the
applicable
State
water
quality
criteria.
If
the
projected
toxicity
exceeds
the
applicable
numeric
water
quality
criterion
for
WET,
there
is
reasonable
potential
that
the
discharge
may
cause
or
contribute
to
an
excursion
above
the
applicable
water
quality
standards
and
the
permit
writer
must
develop
a
WQBEL
for
WET.

Reasonable
Potential
and
Narrative
Criteria
If
the
permit
writer
determines
that
a
discharge
causes,
has
the
reasonable
potential
to
cause,
or
contributes
to
an
in­
stream
excursion
above
a
narrative
criterion,
the
permit
must
contain
effluent
limits
for
WET
unless
the
permit
writer
demonstrates
that
chemical­
specific
limits
for
the
effluent
are
sufficient
to
attain
and
maintain
applicable
numeric
and
narrative
water
quality
criteria.

The
permit
writer
must
investigate
effluents
for
the
presence
of
specific
chemicals
for
which
the
State
has
not
adopted
numeric
criteria,
but
which
may
be
contributing
to
an
excursion
above
a
narrative
criterion.
In
such
cases,
permit
writers
must
establish
limits
using
one
of
three
options:
(
1)
use
EPA's
national
criteria,
(
2)

develop
their
own
criteria,
or
(
3)
control
the
pollutant
through
the
use
of
an
indicator.

100
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Effluent
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Chapter
6
General
Considerations
When
determining
whether
WQBELs
are
needed
in
a
permit,
the
permit
writer
is
required
to
consider,
at
a
minimum:
(
1)
existing
controls
on
point
and
nonpoint
sources
of
pollution;
(
2)
the
variability
of
the
pollutant
or
pollutant
parameter
in
the
effluent;
(
3)
the
sensitivity
of
the
species
to
toxicity
testing;
and
(
4)
where
appropriate,

the
dilution
of
the
effluent
in
the
receiving
water
(
40
CFR
§
122.44(
d)(
ii)).
The
permit
writer
also
must
consider
whether
technology­
based
limits
are
sufficient
to
maintain
State
water
quality
standards.
Finally,
the
permit
writer
should
consider
other
available
data
and
information
pertaining
to
the
discharger
(
e.
g.,
compliance
history,

in­
stream
survey
data,
dilution,
data
from
similar
facilities)
in
addition
to
effluent
monitoring
data
to
assist
in
making
an
informed
reasonable
potential
determination.

6.3.2
Determining
Reasonable
Potential
With
Effluent
Monitoring
Data
When
characterizing
an
effluent
for
the
need
for
a
WQBEL,
the
permit
writer
should
use
any
available
effluent
monitoring
data
as
well
as
other
information
pertaining
to
the
discharge
(
e.
g.,
type
of
industry,
compliance
history,
stream
surveys)

as
the
basis
for
a
decision.
The
permit
writer
may
already
have
effluent
data
available
from
previous
monitoring,
or
he
or
she
may
decide
to
require
the
permittee
to
generate
effluent
monitoring
data
prior
to
permit
issuance
or
as
a
condition
of
the
issued
permit.
EPA
recommends
monitoring
data
be
generated
prior
to
permit
limit
development
for
the
following
reasons:
(
1)
the
presence
or
absence
of
a
pollutant
can
be
more
clearly
established
or
refuted;
and
(
2)
effluent
variability
can
be
more
clearly
defined.
Data
collection
should
begin
far
enough
in
advance
of
permit
development
to
allow
sufficient
time
for
conducting
toxicity
tests
and
chemical
analyses.

The
permit
writer
can
use
the
available
effluent
data
and
a
water
quality
model
to
perform
a
reasonable
potential
analysis.
The
mass
balance
equation,
presented
in
Exhibit
6­
2,
is
a
simple
water
quality
model
that
can
be
used
for
this
analysis.
The
permit
writer
would
use
the
maximum
observed
effluent
concentration,
or
a
statistically
projected
worst­
case
value,
to
calculate
a
projected
in­
stream
concentration,
under
critical
stream
conditions.
The
permit
writer
would
then
compare
the
projected
receiving
water
concentration
to
the
applicable
water
quality
criteria
to
determine
whether
a
water
quality­
based
effluent
limit
is
needed.

NPDES
Permit
Writers'
Manual
­
101
Chapter
6
Water
Quality­
Based
Effluent
Limits
All
toxic
effects
testing
and
exposure
assessment
parameters,
for
both
effluent
EXHIBIT
6­
2
Basic
Mass
Balance
Water
Quality
Equation
QdCd
+
QsCs
=
QrCr
Qd
=
waste
discharge
flow
in
million
gallons
per
day
(
mgd)
or
cubic
feet
per
second
(
cfs)

Cd
=
pollutant
concentration
in
waste
discharge
in
milligrams
per
liter
(
mg/
l)

Qs
=
background
stream
flow
in
mgd
or
cfs
above
point
of
discharge
Cs
=
background
in­
stream
pollutant
concentration
in
mg/
l
Qr
=
resultant
in­
stream
flow,
after
discharge
in
mgd
or
cfs
Cr
=
resultant
in­
stream
pollutant
concentration
in
mg/
l
in
the
stream
reach
(
after
complete
mixing
occurs)

toxicity
and
individual
chemicals,
have
some
degree
of
uncertainty
associated
with
them.
The
more
limited
the
amount
of
data,
the
larger
the
uncertainty.
To
better
characterize
the
effects
of
effluent
variability
and
reduce
uncertainty
in
the
process
of
deciding
whether
to
require
an
effluent
limit
EPA
has
developed
a
statistical
approach
to
determining
reasonable
potential.
This
approach
is
described
in
detail
in
Chapter
3
of
the
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control
18
(
hereafter
referred
to
as
the
"
TSD").
The
statistical
approach
combines
knowledge
of
effluent
variability
with
the
uncertainty
due
to
a
limited
number
of
data
to
project
an
estimated
maximum
concentration
for
the
effluent.
This
projected
maximum
concentration,
after
considering
dilution,
can
then
be
compared
to
an
appropriate
water
quality
criterion
to
determine
the
need
for
an
effluent
limit.

Example:

Q
s
=
Available
dilution
from
upstream
river
flow
=
1.2
cfs
Q
d
=
Discharge
flow
=
0.31
cfs
C
s
=
Upstream
river
concentration
=
0.8
mg/
l
C
d
=
Statistically
projected
maximum
discharge
concentration
=
2.0
mg/
l
C
r
=
Receiving
water
concentration
Water
Quality
Criterion
=
1.0
mg/
l
C
r
=
1.05
mg/
l
Discussion:
Since
the
downstream
concentration
(
C
r)
exceeds
the
water
quality
criterion,
there
is
a
reasonable
potential
for
water
quality
standards
to
be
exceeded.

18USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

102
­
NPDES
Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
Example:

C
r
=
Receiving
water
(
downstream)
concentration
(
in
toxic
units)
C
s
=
Receiving
water
background
concentration
=
0
TU
Q
s
=
Receiving
water
flow
=
23.6
cfs
(
for
acute
protection)
70.9
cfs
(
the
7Q10
for
chronic
protection)
Q
d
=
Discharge
flow
=
7.06
cfs
C
d
=
Discharge
TUa
=
2.49
TUa
TUc
=
6.25
TUc
Q
r
=
Downstream
flow
=
Q
d
+
Q
s
Water
quality
criterion
for
acute
protection
=
0.3
TUa
Water
quality
criterion
for
chronic
protection
=
1.0
TUc
Discussion:
Since
the
downstream
concentration
(
C
r)
exceeds
the
water
quality
criterion
for
acute
toxicity
(
0.3
TUa),
there
is
reasonable
potential
for
water
quality
standards
for
toxicity
to
be
exceeded.

6.3.3
Determining
Reasonable
Potential
Without
Effluent
Monitoring
Data
If
the
permit
writer
so
chooses,
or
if
the
circumstances
dictate,
he
or
she
may
decide
to
develop
and
impose
a
WQBEL
without
facility­
specific
effluent
monitoring
data.
WQBELs
can
be
set
for
a
single
parameter
or
WET
based
on
the
available
dilution
and
the
water
quality
criterion
or
State
standard
in
the
absence
of
facilityspecific
effluent
monitoring
data.
In
justifying
a
limit,
the
more
information
the
permit
writer
can
acquire
to
support
the
limit,
the
better
will
be
the
regulatory
authority's
position
in
defending
the
limit,
if
necessary.
Types
of
information
that
the
permit
writer
may
find
useful
include:
type
of
industry
or
POTW,
existing
data
on
toxic
pollutants,

history
of
compliance
problems
and
toxic
impact,
and
type
of
receiving
water
and
designated
use.
The
permit
writer
must
provide
adequate
justification
for
the
limit
in
the
permit
development
rationale
or
in
the
permit
fact
sheet.
The
permit
writer
may
NPDES
Permit
Writers'
Manual
­
103
Chapter
6
Water
Quality­
Based
Effluent
Limits
well
find
that
he
or
she
would
benefit
from
the
collection
of
effluent
monitoring
data
prior
to
establishing
the
limit.
The
TSD19
provides
guidance
on
collecting
monitoring
data
for
establishing
WQBELs.

If
the
permit
writer,
after
evaluating
all
available
information
on
the
effluent,
in
the
absence
of
effluent
monitoring
data,
is
not
able
to
decide
whether
the
discharge
causes,
has
the
reasonable
potential
to
cause,
or
contributes
to
an
excursion
above
a
numeric
or
narrative
criterion
for
WET
or
for
individual
toxicants,
the
permit
writer
should
require
WET
or
chemical­
specific
testing
to
gather
further
data.
In
such
cases,

the
permit
writer
can
require
the
monitoring
prior
to
permit
issuance,
if
sufficient
time
exists,
or
may
require
the
testing
as
a
condition
of
the
issued
(
or
reissued)
permit.

The
permit
writer
could
then
include
a
clause
in
the
permit
that
would
allow
the
permitting
authority
to
reopen
the
permit
and
impose
an
effluent
limit
if
the
effluent
testing
establishes
that
there
is
reasonable
potential
that
the
discharge
will
cause
or
contribute
to
an
excursion
above
a
water
quality
criterion.

6.4
Exposure
Assessment
and
Wasteload
Allocation
Before
calculating
a
WQBEL,
the
permit
writer
must
first
determine
the
point
source's
wasteload
allocation
(
WLA).
The
WLA
is
the
fraction
of
a
total
maximum
daily
load
(
TMDL)
for
the
water
body
that
is
assigned
to
the
point
source.
This
section
discusses
the
concepts
of
the
TMDL
and
WLA,
describes
methods
for
assessing
exposure
to
pollutants
in
the
receiving
water,
and
explains
how
WLAs
for
a
point
source
are
calculated.

6.4.1
Total
Maximum
Daily
Loads
A
TMDL
is
a
determination
of
the
amount
of
a
pollutant,
or
property
of
a
pollutant,
from
point,
nonpoint,
and
natural
background
sources,
including
a
margin
of
safety,
that
may
be
discharged
to
a
water
quality­
limited
water
body.
Any
loading
above
this
capacity
risks
violating
water
quality
standards.
TMDLs
can
be
expressed
in
terms
of
chemical
mass
per
unit
of
time,
by
toxicity,
or
by
other
appropriate
measures.
Exhibit
6­
3
provides
a
graphic
illustration
of
allocations
under
a
TMDL.

19USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

104
­
NPDES
Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
Section
303(
d)
of
the
CWA
established
the
TMDL
process
to
provide
for
more
EXHIBIT
6­
3
Components
of
a
TMDL
stringent
water
quality­
based
controls
when
technology­
based
controls
are
inadequate
to
achieve
State
water
quality
standards.
These
statutory
requirements
were
codified
at
40
CFR
§
130.7.
When
implemented
accordingly,
the
TMDL
process
can
broaden
the
opportunity
for
public
comment,
expedite
water
quality­
based
NPDES
permitting,

and
lead
to
technically
sound
and
legally
defensible
decisions
for
attaining
and
maintaining
water
quality
standards.
Also,
the
TMDL
process
provides
a
mechanism
for
integrating
point
and
nonpoint
pollutant
sources
into
one
evaluation.

Based
on
the
TMDL,
point
source
WLAs
and
nonpoint
source
load
allocations
(
LAs)
are
established
so
that
predicted
receiving
water
concentrations
do
not
exceed
water
quality
criteria.
TMDLs,
WLAs,
and
LAs
are
established
at
levels
necessary
to
attain
and
maintain
the
applicable
narrative
and
numerical
water
quality
standards,

with
seasonal
variations
and
a
margin
of
safety
that
account
for
any
lack
of
knowledge
concerning
the
relationship
between
point
source
and
nonpoint
source
loadings
and
water
quality.

In
some
cases,
the
waterbody
segment
under
consideration
may
contain
only
one
point
source
discharger.
In
this
situation,
States
typically
develop
a
simple
TMDL
NPDES
Permit
Writers'
Manual
­
105
Chapter
6
Water
Quality­
Based
Effluent
Limits
that
considers
the
point
source
and
background
contributions
of
a
pollutant
from
other
sources.
For
other
waterbody
segments,
a
TMDL
may
not
be
available
at
the
time
the
permit
must
be
issued,
or
a
TMDL
may
not
be
required
at
all.
In
such
cases,

permitting
authorities
have
historically
developed
a
single
WLA
for
a
point
source
discharging
to
the
waterbody
segment.
Both
simple
TMDLs
and
single
WLAs
commonly
rely
on
mass
balance
and
simplified
water
quality
models
which
assume
steady­
state,
or
constant
conditions
for
variables
such
as
background
pollutant
concentrations
and
stream
flow.
EPA
has
encouraged
States
to
develop
TMDLs
for
more
difficult
water
quality
problems
involving
multiple
point
and
nonpoint
source
pollutant
loads.
These
types
of
TMDLs
require
complex
water
quality
models
capable
of
simulating
rainfall
events
and
analyzing
cumulative
chemical
fate
and
transport.

Simple,
steady­
state
modeling
and
more
complex,
dynamic
modeling
are
discussed
in
greater
detail
in
Section
6.4.3
below.

EPA
is
supporting
innovative
approaches
linked
to
developing
and
implementing
TMDLs,
such
as
watershed­
based
trading.
Trading
means
that
pollution
sources
can
sell
or
barter
their
ability
to
reduce
pollution
with
other
sources
that
are
unable
to
reduce
their
pollutant
loads
as
economically.
TMDLs
provide
a
basis
for
successful
trading
because
they
can
be
adapted
to
incorporate
trades,
and
because
the
data
and
analyses
generated
in
TMDLs
allow
water
quality
managers
to
better
understand
and
predict
the
effects
of
proposed
trades.
The
success
of
trading
will
rely
on
reasonable
assurance
that
a
TMDL
will
be
implemented.

Further
guidance
related
to
establishing
TMDLs
can
be
found
in
Chapter
4
of
EPA's
TSD20
and
in
the
Guidance
for
Water
Quality­
Based
Decisions:
The
TMDL
Process.
21
6.4.2
Calculating
Wasteload
Allocations
Before
calculating
a
WQBEL,
the
permit
writer
must
first
know
the
WLA
for
the
point
source
involved.
As
discussed
above,
the
WLA
is
the
fraction
of
a
receiving
20USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

21USEPA
1991,
Guidance
for
Water
Quality­
Based
Decisions:
The
TMDL
Process.
EPA­
440/
4­
91­
0001.
Office
of
Water.

106
­
NPDES
Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
water's
TMDL
that
is
allocated
to
one
of
its
existing
or
future
point
sources
of
pollution.

The
appropriate
WLA
is
determined
through
an
exposure
assessment.
Water
quality
models
are
the
primary
tools
utilized
by
regulatory
agencies
in
conducting
an
exposure
assessment
to
determine
a
WLA.
Models
establish
a
quantitative
relationship
between
a
waste's
load
and
its
impact
on
water
quality.
Modeling
is
usually
conducted
by
a
specialized
work
group
within
the
regulatory
agency;
however,
it
is
important
that
the
permit
writer
understand
this
process.
The
permit
writer
will
use
the
end
result
of
the
model,
a
WLA,
to
derive
a
WQBEL.

6.4.3
Selecting
a
Water
Quality
Model
Determining
which
model
is
appropriate
for
a
given
discharge
and
receiving
water
is
based
upon
whether
or
not
there
is
rapid
and
complete
mixing
of
the
effluent
with
the
receiving
water.
If
the
receiving
water
does
not
have
rapid
and
complete
mixing,
a
mixing
zone
assessment
is
recommended.
If
there
is
rapid
and
complete
mixing
near
the
discharge
point,
a
complete
mix
assessment
involving
fate
and
transport
models
is
recommended.

Mixing
Zone
Assessment
In
incompletely
mixed
discharge
receiving
water
situations,
mixing
zone
modeling
is
appropriate.
Mixing
zones
are
areas
where
an
effluent
undergoes
initial
dilution
and
are
extended
to
cover
secondary
mixing
in
the
ambient
water
body.
A
mixing
zone
is
an
allocated
impact
zone
in
the
receiving
water
where
acute
and
chronic
water
quality
criteria
can
be
exceeded
as
long
as
toxic
conditions
are
prevented
and
the
designated
use
of
the
water
is
not
impaired
as
a
result
of
the
mixing
zone.

The
CWA
allows
mixing
zones
at
the
discretion
of
the
State.
Individual
State
policy
determines
whether
or
not
a
mixing
zone
is
allowed.
EPA
recommends
that
States
make
a
definitive
statement
in
their
water
quality
standards
on
whether
or
not
mixing
zones
are
allowed
and
how
they
will
be
defined.
EPA
provides
guidance
on
when
to
require
a
mixing
zone
and
how
to
determine
the
boundaries
and
size
of
a
mixing
zone.

NPDES
Permit
Writers'
Manual
­
107
Chapter
6
Water
Quality­
Based
Effluent
Limits
In
general,
there
are
two
stages
of
mixing:
discharge­
induced
and
ambient
induced.
The
first
stage
is
controlled
by
discharge
jet
momentum
and
buoyancy
of
the
effluent.
This
stage
generally
covers
most
of
the
mixing
zone
allowed
by
State
water
quality
standards.
Beyond
the
point
of
discharge­
induced
mixing,
mixing
is
controlled
by
ambient
turbulence.
Both
discharge­
induced
mixing
and
ambient­
induced
mixing
models
are
available
for
mixing
zone
analyses.
The
Water
Quality
Standards
Handbook
22
and
Chapter
4
of
the
TSD23
provide
further
guidance
on
mixing
zones
and
how
to
conduct
a
mixing
zone
analysis.

Complete
Mix
Assessment
If
the
distance
from
the
outfall
to
complete
mixing
is
insignificant,
then
mixing
zone
modeling
is
not
necessary.
For
completely
mixed
discharge
receiving
water
situations,
there
are
two
major
types
of
fate
and
transport
water
quality
models:
steady­
state
and
dynamic.
Model
selection
depends
on
the
characteristics
of
the
receiving
water,
the
availability
of
effluent
data,
and
the
level
of
sophistication
desired.
The
minimum
data
required
for
model
input
include
receiving
water
flow,
effluent
flow,
effluent
concentrations,
and
background
pollutant
concentrations.

a.
Steady­
State
Modeling
A
steady­
state
model
requires
single,
constant
inputs
for
effluent
flow,
effluent
concentration,
background
receiving
water
concentration,
receiving
water
flow,
and
meteorological
conditions
(
e.
g.,
temperature).
If
only
a
few
pollutant
or
effluent
toxicity
measurements
are
available
or
if
a
daily
receiving
water
flow
record
is
not
available,
steady­
state
assessments
should
be
used.
Steady­
state
models
calculate
WLAs
at
critical
conditions
that
are
usually
combinations
of
worst­
case
assumptions
of
receiving
water
flow,
effluent
pollutant
concentrations,
and
environmental
effects.
For
example,
a
steady­
state
model
for
ammonia
considers
the
maximum
effluent
discharge
to
occur
on
the
day
of
the
lowest
river
flow,
highest
upstream
concentration,
highest
pH,
and
highest
temperature.
WLAs
and
permit
limits
derived
from
a
steady­
state
model
will
be
22USEPA
(
1994).
Water
Quality
Standards
Handbook:
Second
Edition.
EPA
823­
B­
94­
005a.
Office
of
Water.

23USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

108
­
NPDES
Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
protective
of
water
quality
standards
at
the
critical
conditions
and
for
all
environmental
conditions
less
than
critical.

Steady­
state
modeling
involves
the
application
of
a
mass
balance
equation
that
allows
the
analyst
to
equate
the
mass
of
pollutants
upstream
of
a
given
point
(
generally
at
a
pollutant
discharge,
tributary
stream
or
lateral
inflow)
to
the
mass
of
pollutants
downstream
after
complete
mixing.
The
basic
formula
for
the
mass
balance
model
was
presented
as
Exhibit
6­
2.
This
model
assumes
that
pollutants
are
conservative
and
additive,
and
considers
only
dilution
as
a
mitigating
factor
affecting
the
pollutant
concentration
in­
stream.
The
formula
can
be
modified
to
account
for
factors
such
as
degradation
or
sorption
of
the
pollutant
(
in
addition
to
dilution)
where
appropriate
and
feasible.
A
number
of
steady­
state
toxicant
fate
and
transport
models
that
consider
factors
affecting
in­
stream
pollutant
concentrations
other
than
dilution
are
available
and
are
discussed
in
Chapter
4
of
the
TSD24.

The
simple
mass
balance
equation
can
be
rearranged
as
follows
to
determine
the
downstream
effect
of
a
particular
discharge
concentration:

The
equation
can
be
further
rearranged
to
determine
the
WLA
necessary
to
achieve
a
given
in­
stream
concentration
(
C
r),
such
as
a
water
quality
criterion:

Example:

Assume
a
stream
has
a
critical
design
flow
of
1.2
cfs
and
a
background
zinc
concentration
of
0.80
mg/
l.
The
State
water
quality
criterion
for
zinc
is
1.0
mg/
l
or
less.
The
WLA
for
a
discharge
of
zinc
with
a
flow
of
200,000
gpd
is
[
Note:
200,000
gpd
=
0.31
cfs]:

C
d
=
[(
1.0)(
0.31+
1.2)-(
0.8)(
1.2)]/
0.31
=
(
1.51-
0.96)/
0.31
=
0.55/
0.31
=
1.77
mg/
l
24USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

NPDES
Permit
Writers'
Manual
­
109
Chapter
6
Water
Quality­
Based
Effluent
Limits
Most
States
have
adopted
both
acute
and
chronic
numeric
criteria
for
at
least
some
pollutants.
As
such,
steady­
state
WLA
models
should
be
used
to
calculate
the
allowable
effluent
load
that
will
meet
criteria
at
the
appropriate
design
up­
stream
flow
for
those
criteria.
Each
State
specifies
the
appropriate
design
up­
stream
flow
at
which
its
water
quality
criteria
should
be
applied.
EPA
recommends
a
design
upstream
flow
for
acute
aquatic
life
criteria
at
the
1Q10
(
1­
day
low
flow
over
a
10­
year
period)
and
for
chronic
aquatic
life
criteria
at
the
7Q10
(
7­
day
low
flow
over
a
10­
year
period).
EPA
also
recommends
that
the
receiving
water
harmonic
mean
flow
be
used
as
the
design
upstream
flow
for
human
health
protection.

Once
a
permit
writer
has
a
WLA
for
each
applicable
criterion,
those
WLAs
must
be
translated
into
long
term
average
effluent
concentrations
and,
subsequently,
maximum
daily
and
average
monthly
permit
limits.
This
process
is
discussed
in
Section
6.5
­
Permit
Limit
Derivation.
Calculating
WLAs
and
the
associated
long­
term
average
effluent
concentrations
for
each
applicable
criteria
and
using
the
most
stringent
long­
term
average
effluent
concentration
to
calculate
permit
limits
will
ensure
that
the
permit
limits
are
protective
of
all
applicable
criteria.

b.
Dynamic
Modeling
If
adequate
receiving
water
flow
and
effluent
concentration
data
are
available
to
estimate
frequency
distributions
of
effluent
concentrations,
one
of
the
dynamic
modeling
techniques
could
be
used
to
develop
WLAs.
In
general,
dynamic
models
account
for
the
daily
variations
of
and
relationships
between
flow,
effluent,
and
environmental
conditions,
and
therefore,
directly
determine
the
actual
probability
that
a
water
quality
standard
will
be
exceeded.
The
three
dynamic
modeling
techniques
recommended
by
EPA
include:
continuous
simulation,
Monte
Carlo
simulation,
and
lognormal
probability
modeling.

°
Continuous
simulation
is
a
fate
and
transport
modeling
technique
that
uses
time
series
input
data
to
predict
receiving
water
quality
concentrations
in
the
same
chronological
order
as
that
of
the
input
variables.

°
Monte
Carlo
simulation
is
a
modeling
technique
that
involves
random
selection
of
sets
of
input
data
for
use
in
repetitive
model
runs
in
order
to
predict
the
probability
distributions
of
receiving
water
quality
concentrations.

°
Lognormal
probabilistic
dilution
is
a
modeling
technique
that
calculates
the
probability
distribution
of
receiving
water
quality
concentrations
from
the
lognormal
probability
distributions
of
the
input
variables.

110
­
NPDES
Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
These
methods
calculate
a
probability
distribution
for
receiving
water
concentrations
rather
than
a
single,
worst­
case
concentration
based
on
critical
conditions.
Thus,
they
determine
the
entire
effluent
concentration
frequency
distribution
required
to
produce
the
desired
frequency
of
criteria
compliance.

Chapter
4
of
the
TSD25
describes
steady­
state
and
dynamic
models
in
detail
and
includes
specific
model
recommendations
for
toxicity
and
individual
toxic
pollutants
for
each
type
of
receiving
water
 
rivers,
lakes,
and
estuaries.
In
addition,
EPA
has
issued
detailed
guidelines
on
the
use
of
fate
and
transport
models
of
individual
toxicants.
Specific
references
for
these
models
may
be
found
in
the
Watershed
Tools
Directory
­
A
Collection
of
Watershed
Tools,

available
through
the
Assessment
and
Watershed
Protection
Division
of
the
Office
of
Wetlands,
Oceans
and
Watersheds
[
available
through
the
internet
at
http://
www.
epa.
gov].
These
manuals
describe
in
detail
the
transport
and
transformation
processes
involved
in
water
quality
modeling.

6.5
Permit
Limit
Derivation
WLAs
are
the
outputs
of
water
quality
models,
and
the
requirements
of
a
WLA
must
be
translated
into
a
permit
limit.
The
goal
of
the
permit
writer
is
to
derive
permit
limits
that
are
enforceable,
adequately
account
for
effluent
variability,
consider
available
receiving
water
dilution,
protect
against
acute
and
chronic
impacts,
account
for
compliance
monitoring
sampling
frequency,
and
assure
attainment
of
the
WLA
and
water
quality
standards.
To
accomplish
these
objectives,
EPA
recommends
that
permitting
authorities
use
the
statistical
permit
limit
derivation
procedure
discussed
in
Chapter
5
of
the
TSD26
with
outputs
from
either
steady­
state
or
dynamic
water
quality
models.
EPA
believes
this
procedure
will
result
in
the
most
defensible,
enforceable,

and
protective
WQBELs
for
both
specific
chemicals
and
WET.

25USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

26ibid.

NPDES
Permit
Writers'
Manual
­
111
Chapter
6
Water
Quality­
Based
Effluent
Limits
6.5.1
Expression
of
Permit
Limits
The
NPDES
regulations
at
40
CFR
§
122.45(
d)
require
that
all
permit
limits
be
expressed,
unless
impracticable,
as
both
average
monthly
limits
(
AMLs)
and
maximum
daily
limits
(
MDLs)
for
all
discharges
other
than
POTWs,
and
as
average
weekly
limits
(
AWLs)
and
AMLs
for
POTWs.
The
MDL
is
the
highest
allowable
discharge
measured
during
a
calendar
day
or
24­
hour
period
representing
a
calendar
day.
The
AML
is
the
highest
allowable
value
for
the
average
of
daily
discharges
obtained
over
a
calendar
month.
The
AWL
is
the
highest
allowable
value
for
the
average
of
daily
discharges
obtained
over
a
calendar
week.

The
objective
is
to
establish
permit
limits
that
result
in
the
effluent
meeting
the
Technical
Note
In
lieu
of
an
AWL
for
POTWs,
EPA
recommends
establishing
an
MDL
(
or
a
maximum
test
result
for
chronic
toxicity)
for
toxic
pollutants
and
pollutant
parameters
in
water
quality
permitting.
This
is
appropriate
for
at
least
two
reasons.
First,
the
basis
for
the
7­
day
average
for
POTWs
derives
from
the
secondary
treatment
requirements.
This
basis
is
not
related
to
the
need
for
assuring
achievement
of
water
quality
standards.
Second,
a
7­
day
average,
which
could
comprise
up
to
seven
or
more
daily
samples,
could
average
out
peak
toxic
concentrations
and
therefore
the
discharge's
potential
for
causing
acute
toxic
effects
would
be
missed.
A
MDL,
which
is
measured
by
a
grab
sample,
would
be
toxicologically
protective
of
potential
acute
toxicity
impacts.

WLA
under
normal
operating
conditions
virtually
all
the
time.
It
is
not
possible
to
guarantee,
through
permit
limits,
that
a
WLA
will
never
be
exceeded.
It
is
possible,

however,
using
the
recommended
permit
limit
derivation
procedures
to
account
for
extreme
values
and
establish
low
probabilities
of
exceedance
of
the
WLA
in
conformance
with
the
duration
and
frequency
requirements
of
the
water
quality
standards.

Since
effluents
are
variable,
and
permit
limits
are
developed
based
on
a
low
probability
of
exceedance,
permit
limits
should
take
effluent
variability
into
consideration
and
ensure
that
the
requisite
loading
from
the
WLA
is
not
exceeded
under
normal
conditions.
In
effect,
the
limits
must
force
treatment
plant
performance
levels
that,
after
considering
acceptable
effluent
variability,
will
only
have
a
low
statistical
probability
of
exceeding
the
WLA
and
will
achieve
the
desired
loadings.

6.5.2
Limits
Derived
from
Steady­
State
Model
Outputs
A
permit
limit
derived
from
a
steady­
state
model
output
depends
on
the
type
of
WLA.
WLAs
based
on
protecting
aquatic
life
will
have
two
results:
acute
and
chronic
112
­
NPDES
Permit
Writers'
Manual
Water
Quality­
Based
Effluent
Limits
Chapter
6
requirements
because
State
water
quality
standards
generally
provide
both
acute
and
chronic
protection
for
aquatic
life.
In
contrast,
WLAs
based
on
protecting
human
health
will
have
only
a
chronic
requirement.
In
either
case,
these
WLA
outputs
need
to
be
translated
into
maximum
daily
limits
and
average
monthly
limits.
The
acute
and
chronic
WLA
can
be
achieved
for
either
specific
chemicals
or
WET
by
using
the
following
methodology
to
derive
permit
limits:

°
Calculate
a
treatment
performance
level
(
frequency
distribution
described
by
a
long­
term
average
or
LTA
and
a
coefficient
of
variation
or
CV)
that
will
allow
the
effluent
to
meet
the
WLA
requirements
modeled
(
there
will
be
a
calculation
for
the
acute
WLA
requirement
and
a
calculation
for
the
chronic
WLA
requirement)

°
For
WET
only,
convert
the
acute
WLA
into
an
equivalent
chronic
WLA
by
multiplying
the
acute
WLA
by
an
acute­
to­
chronic
ratio
(
ACR)
(
e.
g.,
2.0
TUa
´
10
=
20
TUc
where
ACR
=
TUc/
TUa
=
10)

°
Derive
permit
limits
directly
from
whichever
performance
level
is
more
protective.

EPA
has
developed
tables
(
see
Tables
5­
1
and
5­
2
in
Chapter
5
of
the
TSD27)

that
permit
writers
can
use
to
quickly
determine
the
values
necessary
to
translate
a
WLA
into
a
permit
limit.
In
addition,
some
permit
authorities
have
developed
their
own
computer
programs
to
compute
WQBELs
from
the
appropriate
inputs.

Some
State
water
quality
criteria
and
the
corresponding
WLAs
are
reported
as
a
single
value
from
which
to
define
an
acceptable
level
of
effluent
quality.
An
example
of
such
a
requirement
is
"
copper
concentration
must
not
exceed
0.75
milligrams
per
liter
(
mg/
l)
in
stream."
Steady
state
analyses
assume
that
the
effluent
is
constant
and
that
the
WLA
value
will
never
be
exceeded.
This
assumption
presents
a
problem
in
deriving
permit
limits
because
permit
limits
need
to
consider
effluent
variability.
Where
there
is
only
one
water
quality
criterion
and
only
one
WLA,
permit
limits
can
be
developed
using
the
following
procedure:

°
Consider
the
single
WLA
to
be
the
chronic
WLA
27USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

NPDES
Permit
Writers'
Manual
­
113
Chapter
6
Water
Quality­
Based
Effluent
Limits
°
Calculate
a
treatment
performance
level
(
an
LTA
and
CV)
that
will
allow
the
effluent
to
meet
the
WLA
requirement
modeled
°
Derive
maximum
daily
and
average
monthly
permit
limits
based
on
the
calculated
LTA
and
CV.

6.5.3
Limits
Derived
from
Dynamic
Model
Outputs
The
least
ambiguous
and
most
exact
way
that
a
WLA
for
specific
chemicals
or
whole
effluent
toxicity
can
be
specified
is
through
the
use
of
dynamic
modeling
from
which
the
wasteload
allocation
is
expressed
as
a
required
effluent
performance
in
terms
of
the
LTA
and
CV
of
the
daily
values.
When
a
WLA
is
expressed
as
such,

there
is
no
confusion
about
assumptions
used
and
the
translation
to
permit
limits.
A
permit
writer
can
readily
design
permit
limits
to
achieve
the
WLA
objectives.
Once
the
WLA
and
corresponding
LTA
and
CV
are
determined,
the
permit
limit
derivation
procedure
found
in
Chapter
5
of
the
TSD28
may
be
used
to
develop
effluent
limits
both
for
specific
chemicals
and
for
whole
effluent
toxicity.

6.5.4
Special
Considerations
Permits
Protecting
Human
Health
Developing
permit
limits
for
pollutants
affecting
human
health
is
somewhat
different
from
setting
limits
for
other
pollutants
because
the
exposure
period
is
generally
longer
than
one
month,
and
can
be
up
to
70
years,
and
the
average
exposure
rather
than
the
maximum
exposure
is
usually
of
concern.
Because
compliance
with
permit
limits
is
normally
determined
on
a
daily
or
monthly
basis,
it
is
necessary
to
set
human
health
permit
limits
that
meet
a
given
WLA
for
every
month.

If
the
procedures
for
aquatic
life
protection
were
used
for
developing
permit
limits
for
human
health
pollutants,
both
the
MDL
and
AML
would
exceed
the
WLA
necessary
to
meet
the
required
criteria
concentrations.
In
addition,
the
statistical
derivation
procedure
is
not
applicable
to
exposure
periods
over
30
days.
Therefore,
the
recommended
approach
for
setting
WQBELs
for
human
health
protection
is
to
set
the
average
monthly
limit
equal
to
the
WLA
and
calculate
the
maximum
daily
limit
based
on
effluent
variability
and
the
number
of
samples
per
month
using
the
statistical
procedures
described
in
Chapter
5
of
the
TSD29.

28USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

29ibid.

114
­
NPDES
Permit
Writers'
Manual
Chapter
7
Monitoring
and
Reporting
Conditions
Having
developed
the
effluent
limits
for
a
municipal
or
industrial
discharger,
the
permit
writer's
next
step
is
to
establish
monitoring
and
reporting
requirements.

Requiring
the
permittee
to
routinely
self­
monitor
its
discharge
and
to
report
the
analytical
results
of
such
monitoring
provides
the
permitting
authority
with
the
information
necessary
to
evaluate
discharge
characteristics
and
compliance
status.

Periodic
monitoring
and
reporting
also
serve
to
remind
the
permittee
of
its
compliance
responsibilities
and
provides
feedback
regarding
the
performance
of
the
treatment
facility(
s)
operated
by
the
permittee.
Permit
writers
should
be
aware
of
and
concerned
with
the
potential
problems
that
may
occur
in
a
self­
monitoring
program
such
as
improper
sample
collection
procedures,
poor
analytical
techniques,
and
poor
or
improper
report
preparation
and
documentation.
To
prevent
or
minimize
these
problems,
the
permit
writer
should
clearly
detail
monitoring
and
reporting
requirements
in
the
permit.

NPDES
Permit
Writers'
Manual
­
115
Chapter
7
Monitoring
and
Reporting
Conditions
The
monitoring
and
reporting
conditions
section
of
a
NPDES
individual
permit
should
contain
specific
requirements
for
the
following
items:

°
Sampling
location
°
Sample
collection
method
°
Monitoring
frequencies
°
Analytical
methods
°
Reporting
and
recordkeeping
requirements.

Several
factors
should
be
considered
in
determining
the
specific
requirements
to
be
imposed.
Basic
factors
that
may
affect
sampling
location,
sampling
method,
and
sampling
frequency
are:

°
Applicability
of
"
effluent
limitations
guidelines"
(
ELG)

°
Effluent
and
process
variability
°
Effect
of
flow
and/
or
pollutant
load
on
the
receiving
water
°
Characteristics
of
pollutants
discharged
°
Permittee
compliance
history.

These
factors
must
be
carefully
considered
by
the
permit
writer,
as
any
error
could
lead
to
inaccurate
compliance
determination,
misapplication
of
national
ELGs,
and/
or
misapplication
of
State
water
quality
standards.

The
following
sections
provide
an
overview
of
the
considerations
involved
in
determining
appropriate
monitoring,
reporting,
and
recordkeeping
requirements,
and
describe
how
to
properly
incorporate
the
requirements
in
a
NPDES
permit.

7.1
Establishing
Monitoring
Conditions
The
NPDES
Program
is
structured
such
that
facilities
that
discharge
pollutants
in
waters
of
the
United
States
are
required
to
periodically
evaluate
compliance
with
the
effluent
limitations
established
in
their
permit
and
provide
the
results
to
the
permitting
authority.
In
addition,
NPDES
permits
can
require
the
permittee
to
monitor
for
additional
parameters
or
processes
not
directly
linked
to
the
effluent
discharge
such
as
storm
water,
combined
sewer
overflows,
municipal
sludge,
and/
or
treatment
plant
influent.
This
section
describes
the
regulatory
requirements
and
authorities
for
116
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
monitoring
conditions,
and
describes
how
these
conditions
can
be
incorporated
in
NPDES
permits.

The
regulations
requiring
the
establishment
of
monitoring
and
reporting
conditions
in
NPDES
permits
are
found
in
40
CFR
§
122.44(
i)
and
40
CFR
§
122.48.

Section
122.44(
i)
requires
permittees
to
monitor
pollutant
mass
(
or
other
applicable
unit
of
measure),
effluent
volume,
provide
other
measurements
(
as
appropriate),
and
to
utilize
the
test
methods
established
at
40
CFR
§
136.
Section
122.41(
i)
also
establishes
that
NPDES
permittees
(
with
certain
specific
exceptions)
must
monitor
for
all
limited
pollutants
and
report
data
at
least
once
per
year.

EPA
regulations
at
40
CFR
§
122.48
state
that
all
permits
must
specify
requirements
concerning
the
proper
use,
maintenance,
and
installation
of
monitoring
equipment
or
methods
(
including
biological
monitoring
methods
when
appropriate).
All
permits
must
also
specify
the
required
monitoring
including
the
type,
intervals,
and
frequency
sufficient
to
yield
data
that
are
representative
of
the
activity.
The
following
sections
focus
on
ensuring
that
permit
monitoring
conditions
properly
address
these
regulatory
requirements.

7.1.1
Monitoring
Location
The
NPDES
regulations
do
not
specify
the
exact
location
to
be
used
for
monitoring.
The
permit
writer
is
responsible
for
determining
the
most
appropriate
monitoring
location
and
explicitly
specifying
this
in
the
permit.
Ultimately,
the
permittee
is
responsible
for
providing
a
safe
and
accessible
sampling
point
that
is
representative
of
the
discharge
(
40
CFR
§
122.41(
j)(
1)).

Specifying
the
appropriate
monitoring
location
in
a
NPDES
permit
is
critical
to
producing
valid
compliance
data.
Important
factors
to
consider
in
selecting
a
monitoring
location
include:

°
The
wastewater
flow
should
be
measurable
°
The
location
should
be
easily
and
safely
accessible
°
The
sample
must
be
representative
of
the
effluent
during
the
time
period
that
is
monitored.

NPDES
Permit
Writers'
Manual
­
117
Chapter
7
Monitoring
and
Reporting
Conditions
The
most
logical
monitoring
point
for
an
effluent
is
just
prior
to
discharge
to
the
Technical
Note
When
establishing
monitoring
locations
for
determining
NPDES
permit
compliance,
permit
writers
must
select
locations
that
are
representative
of
the
expected
wastewater
discharge.
Locations
should
be
established
where
the
wastewater
is
well
mixed,
such
as
near
a
parshall
flume
or
at
a
location
in
a
sewer
with
hydraulic
turbulence.
Weirs
tend
to
enhance
the
settling
of
solids
immediately
upstream
and
the
accumulation
of
floating
oil
or
grease
immediately
downstream.
Such
locations
should
be
avoided
for
sampling.

receiving
water.
This
is
particularly
true
for
ensuring
compliance
with
water
qualitybased
effluent
limits
(
WQBELs).
However,
there
are
instances
when
the
permit
writer
may
need
to
specify
alternate
monitoring
locations
in
a
permit.

One
typical
instance
that
necessitates
establishing
an
alternative
monitoring
location
occurs
when
a
facility
combines
a
variety
of
process
and
non­
process
wastewaters
prior
to
discharge
through
a
common
outfall
structure.
Under
certain
circumstances,
when
a
variety
of
wastewaters
are
combined,
requiring
monitoring
only
at
the
final
combined
outfall
may
not
be
appropriate.
To
address
this
situation,
40
CFR
§
122.45(
h)
allows
permit
writers
to
establish
monitoring
locations
at
internal
outfalls.
Examples
of
situations
that
may
require
designation
of
internal
monitoring
locations
include:

°
To
ensure
compliance
with
effluent
limitations
guidelines
and
standards
(
at
non­
municipal
facilities)
 
When
non­
process
wastewaters
dilute
process
wastewaters
regulated
under
effluent
guidelines,
monitoring
the
combined
discharge
may
not
accurately
depict
whether
the
facility
is
complying
with
the
effluent
guidelines.
Under
these
circumstances,
the
permit
writer
may
consider
requiring
monitoring
for
compliance
with
technology­
based
effluent
limits
(
based
on
application
of
effluent
guidelines)
before
the
process
wastewater
is
combined
with
the
other
wastewaters.

°
To
ensure
compliance
with
secondary
treatment
standards
(
for
POTWs
only)
 
Certain
POTWs
include
treatment
processes
that
are
ancillary
to
the
secondary
treatment
process
that
may
impact
their
ability
to
monitor
for
compliance
with
secondary
treatment
standards.
Under
these
circumstances,
the
permit
writer
may
consider
requiring
monitoring
for
compliance
with
secondary
treatment
standards
just
after
the
secondary
treatment
process
(
e.
g.,
require
monitoring
of
effluent
just
after
secondary
clarification)
before
any
additional
treatment
processes.

°
To
allow
detection
of
a
pollutant
 
Instances
may
arise
where
the
combination
of
process
and
non­
process
wastewaters
result
in
dilution
of
a
pollutant
of
concern
that
will
not
be
detectable
using
approved
analytical
118
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
methods.
Establishing
monitoring
for
the
pollutant
at
an
internal
location
will
enable
characterization
of
the
pollutant
prior
to
dilution
with
other
wastewaters.

When
establishing
internal
monitoring
points,
permit
writers
need
to
consider
the
location
of
wastewater
treatment
units
within
the
facility.
This
is
particularly
true
when
establishing
internal
monitoring
locations
for
determining
compliance
with
technology­
based
effluent
limits.
A
facility
will
most
likely
not
be
able
to
comply
with
technology­
based
effluent
limits
if
the
permit
writer
establishes
the
monitoring
location
prior
to
the
wastewater
treatment
unit.

Permit
writers
may
also
need
to
require
monitoring
of
influent
to
the
wastewater
treatment
units
for
certain
facilities.
Influent
monitoring
must
be
required
for
POTWs
to
ensure
compliance
with
the
85
percent
removal
condition
of
the
secondary
treatment
standards.
Influent
monitoring
at
non­
POTWs
may
also
be
desired
to
determine
influent
characteristics,
and
if
additional
information
related
to
the
performance
of
the
wastewater
treatment
unit
is
needed.

Exhibit
7­
1
provides
examples
of
how
to
specify
sampling
locations
in
a
permit
either
by
narrative
or
diagram.

7.1.2
Monitoring
Frequency
The
frequency
for
monitoring
pollutants
should
be
determined
on
a
case­

bycase
basis,
and
decisions
for
setting
the
frequency
should
be
set
forth
in
the
fact
sheet.
Some
States
have
their
own
recommended
sampling
guidelines
that
can
help
a
permit
writer
determine
an
appropriate
sampling
frequency.
The
intent
is
to
establish
a
frequency
of
monitoring
that
will
detect
most
events
of
noncompliance
without
requiring
needless
or
burdensome
monitoring.

To
establish
a
monitoring
frequency,
the
permit
writer
should
estimate
the
variability
of
the
concentration
of
the
parameter
by
reviewing
effluent
data
for
the
facility
(
e.
g.,
from
DMRs)
or
in
the
absence
of
actual
data,
information
from
similar
dischargers.
A
highly
variable
discharge
should
require
more
frequent
monitoring
than
a
discharge
that
is
relatively
consistent
over
time
(
particularly
in
terms
of
flow
and
NPDES
Permit
Writers'
Manual
­
119
Chapter
7
Monitoring
and
Reporting
Conditions
EXHIBIT
7­
1
Examples
of
Specifying
Sampling
Locations
in
Permits
NARRATIVE:

Part
I.
SELF­
MONITORING
REQUIREMENTS
A.
Sample
Locations
1.
Discharge
from
the
Chemistry­
Fine
Arts
Building
shall
be
sampled
at
outfall
001
2.
Discharge
from
the
Duane
Physics
Building
shall
be
sampled
at
outfall
002
3.
Discharge
from
the
Research
Lab
No.
1
shall
be
sampled
at
outfall
003
DIAGRAM:

Part
I.
EFFLUENT
LIMITATIONS
AND
MONITORING
REQUIREMENTS
A.
Sample
Locations
Outfall
Description
001
Discharge
Pipe
 
Discharge
of
wastewater
generated
by
all
regulated
metal
finishing
processes
at
the
facility.
Samples
shall
be
collected
at
the
point
indicated
on
the
attached
diagram.

Outfall
001
Parshall
Flume
Final
pH
Adjustment
Tank
*
Sample
Point
*

894B­
04
Receiving
Stream
pollutant
concentration).
In
addition
to
the
estimated
variability,
other
factors
that
should
be
considered
when
establishing
appropriate
monitoring
frequencies
include:

°
Design
capacity
of
treatment
facility
 
As
an
example,
at
equivalent
average
flow
rates,
a
large
lagoon
system
that
is
not
susceptible
to
bypasses
requires
less
frequent
monitoring
than
an
overloaded
treatment
facility
that
experiences
fluctuating
flow
rates
due
to
infiltration
or
large
batch
discharges
from
an
industrial
user
system.
The
lagoon
should
have
a
relatively
low
variability
compared
to
the
facility
receiving
batch
discharges.

120
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
°
Type
of
treatment
method
used
 
The
type
of
wastewater
treatment
used
by
the
facility
will
determine
the
need
for
process
control
monitoring
and
effluent
monitoring.
An
industrial
facility
with
biological
treatment
would
have
similar
monitoring
frequencies
to
a
secondary
treatment
plant
with
the
same
units
used
for
wastewater
treatment.
If
the
treatment
method
is
appropriate
and
achieving
high
pollutant
removals
on
a
consistent
basis,
the
need
for
monitoring
may
be
less
than
a
plant
with
little
treatment
or
insufficient
treatment.

°
Post
compliance
record/
history
 
The
monitoring
frequency
may
be
adjusted
to
reflect
the
compliance
history
of
the
facility.
A
facility
with
problems
achieving
compliance
generally
should
be
required
to
perform
additional
monitoring
to
characterize
the
source
or
cause
of
the
problems
or
to
detect
noncompliance.

°
Cost
of
monitoring
relative
to
discharger's
capabilities
 
The
permit
writer
should
not
require
excessive
monitoring
unless
it
is
necessary
to
provide
sufficient
information
about
the
discharge
(
analytical
costs
are
addressed
in
Section
7.1.5).

°
Frequency
of
the
discharge
 
If
wastewater
is
discharged
in
batches
on
an
infrequent
basis,
the
monitoring
frequency
should
be
different
from
a
continuously
discharged,
highly
concentrated
wastewater,
or
a
wastewater
containing
a
pollutant
that
is
found
infrequently
and
at
very
low
concentrations.
The
production
schedule
of
the
facility
(
e.
g.,
seasonal,
daily),
the
plant
washdown
schedule,
and
other
similar
factors
should
be
considered.

°
Number
of
monthly
samples
used
in
developing
permit
limit
 
The
monitoring
frequency
should
reflect
the
number
of
monthly
samples
used
in
developing
the
permit
limits,
and/
or
the
monitoring
frequencies
used
to
develop
any
applicable
effluent
guidelines.

°
Tiered
Limits
 
Where
the
permit
writer
has
included
"
tiered"
limits
in
an
NPDES
permit,
consideration
should
be
given
to
varying
the
monitoring
frequency
requirements
to
correspond
to
the
applicable
tiers.
For
example,
if
a
facility
has
seasonal
discharge
limits,
it
may
be
appropriate
to
increase
the
monitoring
frequency
during
the
higher
production
season,
and
reduce
the
frequency
during
the
off­
season.

An
alternative
method
that
can
be
used
by
permit
writers
to
establish
monitoring
frequencies
is
the
quantitative
approach
described
in
the
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control
(
TSD)
30.
In
short,
the
TSD31
approach
30USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

31ibid.

NPDES
Permit
Writers'
Manual
­
121
Chapter
7
Monitoring
and
Reporting
Conditions
requires
calculating
the
long­
term
average
pollutant
concentration
(
accounting
for
the
expected
variability
of
the
discharge)
and
comparing
it
to
the
permit
limit
to
determine
the
likelihood
of
noncompliance.
The
closer
the
long­
term
average
is
to
the
permit
limit,
the
more
frequent
the
monitoring
that
should
be
required.
Obviously,
this
quantitative
approach
requires
a
reasonable
data
set
from
which
to
calculate
the
longterm
average.
Permit
writers
should
refer
to
the
TSD32
for
more
information
regarding
this
approach.

A
permit
writer
may
also
establish
a
tiered
monitoring
schedule
that
reduces
or
increases
monitoring
frequency
during
a
permit
cycle.
Tiered
monitoring,
which
reduces
monitoring
over
time,
may
be
useful
for
discharges
where
the
initial
sampling
shows
compliance
with
effluent
limits.
If
problems
are
found
during
the
initial
sampling,
more
frequent
sampling
and
more
comprehensive
monitoring
can
be
applied.
This
step­
wise
approach
could
lead
to
lower
monitoring
costs
for
permittees
while
still
providing
an
adequate
degree
of
protection
of
water
quality.

Regulatory
Update
In
response
to
President
Clinton's
Regulatory
Reinvention
initiative,
which
established
the
goal
of
reducing
monitoring
and
reporting
burden
by
25%,
EPA
issued
Interim
Guidance
for
Performance­
Based
Reductions
of
NPDES
Permit
Monitoring
Frequencies
on
April
19,
1996
(
EPA­
833­
B­
96­
001).
Under
this
guidance,
NPDES
reporting
and
monitoring
requirements
are
reduced
based
on
a
demonstration
of
excellent
historical
performance.
Facilities
can
demonstrate
this
historical
performance
by
meeting
a
set
of
compliance
and
enforcement
criteria
and
by
demonstrating
their
ability
to
consistently
discharge
pollutants
below
the
levels
necessary
to
meet
their
existing
NPDES
permit
limits.
Reductions
are
determined
parameter­
by­
parameter,
based
on
the
existing
monitoring
frequency
and
the
percentage
below
the
limit
that
parameter
is
being
discharged
at.
The
reductions
are
incorporated
into
the
permit
at
the
time
of
permit
reissuance.
To
remain
eligible
for
these
reductions,
permittees
are
expected
to
maintain
parameter
performance
levels
and
good
compliance
and
enforcement
history
that
were
used
as
the
basis
for
granting
the
reductions.

7.1.3
Sample
Collection
Methods
In
addition
to
establishing
the
frequency
of
monitoring,
the
permit
writer
must
specify
the
type
of
sample
that
must
be
collected.
The
two
basic
sample
collection
methods
include
"
grab"
and
"
composite."

The
analytical
methods
specified
in
40
CFR
Part
136
are
required
for
all
monitoring
performed
under
the
NPDES
Program,
unless
the
permit
specifically
32USEPA
(
1991).
Technical
Support
Document
for
Water
Quality­
Based
Toxics
Control.
EPA­
505/
2­
90­
001.
Office
of
Water
Enforcement
and
Permits.

122
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
requires
alternate
methods.
For
many
analytical
procedures,
the
sample
collection
method
(
grab
or
composite)
is
not
specified
in
40
CFR
Part
136,
thus
it
should
be
specified
in
the
discharge
permit.
40
CFR
Part
136
specifies
that
grab
samples
must
be
collected
for
pH,
temperature,
dissolved
oxygen,
chlorine,
purgeable
organics,

sulfides,
oil
and
grease,
coliform
bacteria
and
cyanide.
The
reason
grab
samples
must
be
taken
for
these
parameters
is
that
they
evaluate
characteristics
that
may
change
during
the
time
necessary
for
compositing.

A
"
grab"
sample
is
a
single
sample
collected
at
a
particular
time
and
place
that
represents
the
composition
of
the
wastestream
only
at
that
time
and
place.
When
the
quality
and
flow
of
the
wastestream
being
sampled
is
not
likely
to
change
over
time,
a
grab
sample
is
appropriate.
Grab
samples
should
be
used
when:

°
The
wastewater
characteristics
are
relatively
constant.

°
The
parameters
to
be
analyzed
are
likely
to
change
with
storage
such
as
temperature,
residual
chlorine,
soluble
sulfide,
cyanides,
phenols,
microbiological
parameters
and
pH.

°
The
parameters
to
be
analyzed
are
likely
to
be
affected
by
the
compositing
process
such
as
oil
and
grease
and
volatiles.

°
Information
on
variability
over
a
short
time
period
is
desired.

°
Composite
sampling
is
impractical
or
the
compositing
process
is
liable
to
introduce
artifacts
of
sampling.

°
The
spatial
parameter
variability
is
to
be
determined.
For
example,
variability
through
the
cross
section
and/
or
depth
of
a
stream
or
a
large
body
of
water.

°
Effluent
flows
are
intermittent
from
well­
mixed
batch
process
tanks.
Each
batch
dumping
event
should
be
sampled.

Grab
samples
can
measure
maximum
effect
only
when
the
sample
is
collected
during
flows
containing
the
maximum
concentration
of
pollutants
toxic
to
the
test
organism.

Another
type
of
grab
sample
is
sequential
sampling.
A
special
type
of
automatic
sampling
device
collects
relatively
small
amounts
of
a
sampled
wastestream,
with
the
interval
between
sampling
either
time
or
flow
proportioned.

Unlike
the
automatic
composite
sampler,
the
sequential
sampling
device
automatically
retrieves
a
sample
and
holds
it
in
a
bottle
separate
from
other
automatically
retrieved
samples.
Many
individual
samples
can
be
stored
separately
in
the
unit,
unlike
the
NPDES
Permit
Writers'
Manual
­
123
Chapter
7
Monitoring
and
Reporting
Conditions
composite
sampler
which
combines
aliquots
in
a
common
bottle.
This
type
of
sampling
is
effective
for
determining
variations
in
effluent
characteristics
over
short
periods
of
time.

A
"
composite"
sample
is
a
collection
of
individual
samples
obtained
at
regular
intervals,
usually
based
upon
time
or
flow
volume.
A
composite
sample
is
desirable
when
the
material
being
sampled
varies
significantly
over
time
either
as
a
result
of
flow
or
quality
changes.
There
are
two
general
types
of
composites
and
the
permit
writer
should
clearly
express
which
type
is
required
in
the
permit:

°
Time
composite
samples
collect
a
fixed
volume
at
equal
time
intervals
and
are
acceptable
when
flow
variability
is
not
excessive.
Automatically
timed
composited
samples
are
usually
preferred
over
manually
collected
composites.
Composite
samples
collected
by
hand
are
appropriate
for
infrequent
analyses
and
screening.

Composite
samples
can
be
collected
manually
if
subsamples
have
a
fixed
volume
at
equal
time
intervals
when
flow
variability
is
not
excessive.

°
Flow­
proportional
compositing
is
usually
preferred
when
effluent
flow
volume
varies
appreciably
over
time.
The
equipment
and
instrumentation
for
flow­
proportional
compositing
have
more
downtime
due
to
maintenance
problems.

When
manually
compositing
effluent
samples
according
to
flow
where
no
flow
measuring
device
exists,
use
the
influent
flow
measurement
without
any
correction
for
time
lag.
The
error
in
the
influent
and
effluent
flow
measurement
is
insignificant
except
in
those
cases
where
extremely
large
volumes
of
water
are
impounded,
as
in
reservoirs.

There
are
numerous
cases
where
composites
are
inappropriate.
Samples
for
some
parameters
should
not
be
composited
(
pH,
residual
chlorine,
temperature,

cyanides,
volatile
organics,
microbiological
tests,
oil
and
grease,
total
phenols).
They
are
also
not
recommended
for
sampling
batch
or
intermittent
processes.
Grab
samples
are
needed
in
these
cases
to
determine
fluctuations
in
effluent
quality.

For
whole
effluent
toxicity
(
WET),
composite
samples
are
used
unless
it
is
known
that
the
effluent
is
most
toxic
at
a
particular
time.
Some
toxic
chemicals
are
short­
lived,
degrade
rapidly,
and
will
not
be
present
in
the
most
toxic
form
after
lengthy
compositing
even
with
refrigeration
or
other
forms
of
preservation.
Grab
samples
should
be
required
for
bioassays
to
be
taken
under
those
circumstances.

124
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
If
a
sampling
protocol
is
not
specified
in
the
regulations,
the
duration
of
the
compositing
time
period
and
frequency
of
aliquot
collection
is
established
by
the
permit
writer.
Whether
collected
by
hand
or
by
an
automatic
device,
the
time
frame
within
which
the
sample
is
collected
should
be
specified
in
the
permit.
The
number
of
individual
aliquots
which
compose
the
composite
should
also
be
specified.
NPDES
application
requirements
specify
a
minimum
of
four
aliquots
for
non­
stormwater
discharges
lasting
four
or
more
hours.

Eight
types
of
composite
samples
and
the
advantages
and
disadvantages
of
each
are
shown
in
Exhibit
7­
2.
As
shown
in
Exhibit
7­
2,
samples
may
be
composited
by
time
or
flow
and
a
representative
sample
will
be
assured.
However,
where
both
flow
and
pollutant
concentration
fluctuate
dramatically,
a
flow­
proportioned
composite
sample
should
be
taken
because
a
greater
quantity
of
pollutant
will
be
discharged
during
these
periods.
As
an
alternative,
time­
proportioned
samples
may
be
taken
with
flow
records
used
for
weighing
the
significance
of
various
samples.

Continuous
monitoring
is
another
option
for
a
limited
number
of
parameters
such
as
flow,
total
organic
carbon
(
TOC),
temperature,
pH,
conductivity,
fluoride
and
dissolved
oxygen.
Reliability,
accuracy
and
cost
of
continuous
monitoring
vary
with
the
parameter.
Continuous
monitoring
can
be
expensive,
so
continuous
monitoring
will
usually
only
be
an
appropriate
requirement
for
the
most
significant
dischargers
with
variable
effluent.
The
environmental
significance
of
the
variation
of
any
of
these
parameters
in
the
effluent
should
be
compared
to
the
cost
of
continuous
monitoring.

Technical
Note
When
establishing
continuous
monitoring
requirements,
the
permit
writer
should
be
aware
that
the
NPDES
regulations
concerning
pH
limits
allow
for
a
period
of
excursion
when
the
effluent
is
being
continuously
monitored
(
40
CFR
§
401.17).

7.1.4
Analytical
Methods
The
permit
writer
must
specify
the
analytical
methods
to
be
used
for
monitoring.

These
are
usually
indicated
as
40
CFR
Part
136
in
the
standard
conditions
of
the
permit
[
40
CFR
§
§
122.41(
j)(
4)
and
122.44(
i)].
In
particular,
analytical
methods
for
industrial
and
municipal
wastewater
pollutants
must
be
conducted
in
accordance
with
NPDES
Permit
Writers'
Manual
­
125
Chapter
7
Monitoring
and
Reporting
Conditions
EXHIBIT
7­
2
Compositing
Methods
Method
Advantages
Disadvantages
Comments
Time
Composite
°
Constant
sample
volume,
constant
time
interval
between
samples
Minimal
instrumentation
and
manual
effort;
requires
no
flow
measurement
May
lack
representativeness,
especially
for
highly
variable
flows
Widely
used
in
both
automatic
samplers
and
manual
handling
Flow­
Proportional
Composite
°
Constant
sample
volume,
time
interval
between
samples
proportional
to
stream
flow
Minimal
manual
effort
Requires
accurate
flow
measurement
reading
equipment;
manual
compositing
from
flowchart
Widely
used
in
automatic
as
well
as
manual
sampling
°
Constant
time
interval
between
samples,
sample
volume
proportional
to
total
stream
flow
at
time
of
sampling
Minimal
instrumentation
Manual
compositing
from
flowchart
in
absence
of
prior
information
on
the
ratio
of
minimum
to
maximum
flow;
chance
of
collecting
too
small
or
too
large
individual
discrete
samples
for
a
given
composite
volume
Used
in
automatic
samplers
and
widely
used
as
manual
method
°
Constant
time
interval
between
samples,
sample
volume
proportional
to
total
stream
flow
since
last
sample
Minimal
instrumentation
Manual
compositing
from
flow
chart
in
absence
of
prior
information
on
the
ratio
of
minimum
to
maximum
flow;
chance
of
collecting
either
too
small
or
too
large
individual
discrete
samples
for
a
given
composite
volume
Not
widely
used
in
automatic
samplers
but
may
be
done
manually
Sequential
Composite
°
Series
of
short
period
composites,
constant
time
intervals
between
samples
Useful
if
fluctuations
occur
and
time
history
is
desired
Requires
manual
compositing
of
aliquots
based
on
flow
Commonly
used;
however,
manual
compositing
is
labor
intensive
°
Series
of
short
period
composites,
aliquots
taken
at
constant
discharge
increments
Useful
if
fluctuations
occur
and
time
history
is
desired
Requires
flow
totalizer;
requires
manual
compositing
of
aliquots
based
on
flow
Manual
compositing
is
labor
intensive
Continuous
Composite
°
Constant
sample
volume
Minimal
manual
effort,
requires
no
flow
measurement
Requires
large
sample
capacity;
may
lack
representativeness
for
highly
variable
flows
Practical
but
not
widely
used
°
Sample
volume
proportional
to
stream
flow
Minimal
manual
effort,
most
representative
especially
for
highly
variable
flows
Requires
accurate
flow
measurement
equipment,
large
sample
volume,
variable
pumping
capacity,
and
power
Not
widely
used
126
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
the
methods
specified
pursuant
to
40
CFR
Part
136,
which
references
one
or
more
of
the
following:

°
Test
methods
in
Appendix
A
of
40
CFR
Part
13633
°
Standard
Methods
for
the
Examination
of
Water
and
Wastewater,
18th
Edition
34
°
Methods
for
the
Chemical
Analysis
of
Water
and
Wastewater
35
°
Test
Methods:
Methods
for
Organic
Chemical
Analysis
of
Municipal
and
Industrial
Wastewater.
36
The
analytical
methods
contained
in
40
CFR
Part
136
are
test
methods
designed
only
for
priority
and
conventional
pollutants,
and
some
nonconventional
pollutants.
In
the
absence
of
analytical
methods
for
other
parameters,
the
permit
writer
must
still
specify
the
analytical
methods
to
be
used.
An
excellent
source
of
analytical
method
information
is
the
Environmental
Monitoring
Methods
Index
(
EMMI).

The
EMMI
is
an
official
EPA
database
linking
50
EPA
regulatory
lists,
2,600
substances
and
926
analytical
methods
on
EMMI.
EMMI
data
correlate
EPA's
regulated
substances
with
their
associated
analytical
methods,
published
detection
limits,
and
regulatory
limits.
For
more
information,
call
NTIS
at
(
703)
321­
8547
for
system
requirements.

7.1.5
Other
Considerations
in
Establishing
Monitoring
Requirements
The
regulations
do
not
specifically
require
a
permit
writer
to
evaluate
costs
when
establishing
monitoring
conditions
in
a
permit.
However,
as
a
practical
matter,

the
permit
writer
should
consider
the
cost
of
sampling
that
he/
she
imposes
on
the
permittee.
The
sample
frequency
and
analyses
impact
the
analytical
cost.
The
estimated
1994­
1995
costs
for
analytical
procedures
are
shown
in
Exhibit
7­
3.

33
Guidelines
Establishing
Test
Procedures
for
the
Analysis
of
Pollutants
Under
the
Clean
Water
Act
(
40
CFR
Part
136).
(
Use
most
current
version)

34American
Public
Health
Association,
American
Water
Works
Association,
and
Water
Pollution
Control
Federation
(
1992).
Standard
Methods
for
the
Examination
of
Water
and
Wastewater,
18th
Ed.

35USEPA
(
1979).
Methods
for
the
Chemical
Analysis
of
Water
and
Wastewater.
EPA­
600/
4­
79­
020.
Environmental
Monitoring
and
Support
Laboratory.

36USEPA
(
1982).
Test
Methods:
Methods
for
Organic
Chemical
Analysis
of
Municipal
and
Industrial
Wastewater.
EPA­
600/
4­
82­
057.

NPDES
Permit
Writers'
Manual
­
127
Chapter
7
Monitoring
and
Reporting
Conditions
EXHIBIT
7­
3
Estimated
Costs
for
Common
Analytical
Procedures1
BOD
5
$
30
TSS
$
15
TOC
$
60
Oil
and
Grease
$
35
Odor
$
30
Color
$
30
Turbidity
$
30
Fecal
coliform
$
15
Metals
(
each)
$
15
Cyanide
$
35
Gasoline
(
Benzene,
Toluene,
Xylene)
$
100
Purgeable
Halocarbons
(
EPA
Method
601)
$
113
Acrolein
and
Acrylonitrile
(
EPA
Method
603)
$
133
Purgeables
(
EPA
Method
624)
$
251
Phenols
(
EPA
Method
604)
$
160
Organochlorine
Pesticides
and
PCBs
(
EPA
Method
608)
$
157
Polynuclear
Aromatic
Hydrocarbons
(
EPA
Method
610)
$
175
Dioxin
(
2,
3,
7,
8­
TCDD
(
EPA
Method
613))
$
400
Base/
Neutrals
and
Acids
(
EPA
Method
625)
$
434
Priority
pollution
scan
2
$
2,000
Acute
WET
$
750
Chronic
WET
$
1,500
1
Based
on
1994
 
1995
costs.

2
Includes
13
metals,
cyanide,
dioxin,
volatiles
(
purgeables),
base/
neutral
and
acids,
pesticides
and
PCBs,
and
asbestos.

128
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
If
simple
or
inexpensive
indicator
parameters
(
e.
g.,
BOD
5
acts
as
an
indicator
for
the
priority
pollutants
in
the
Wood
and
Gum
Chemicals
category)
or
alternate
parameters
will
produce
data
representative
of
the
pollutant
present
in
the
discharge,
then
the
indicators
or
surrogate
pollutants
or
parameters
should
be
considered.
Complex
and
expensive
sampling
requirements
may
not
be
appropriate
if
the
permit
writer
cannot
justify
the
need
for
such
analyses.

7.1.6
Establishing
Monitoring
Conditions
for
Unique
Discharges
There
are
a
variety
of
discharges
that
are
regulated
under
the
NPDES
permit
program
that
are
different
than
traditional
wastewater
discharges.
A
permit
writer
needs
to
account
for
these
unique
discharges
in
establishing
monitoring
requirements.

This
section
discusses
several
of
these
unique
discharges
including
storm
water,

combined
sewer
and
sanitary
sewer
overflows,
WET,
and
municipal
sludge.

Storm
Water
Monitoring
Considerations
Monitoring
requirements
vary
according
to
the
type
of
permit
regulating
the
storm
water
discharge
and
the
activity.
Storm
water
discharges
may
be
regulated
by
State
programs,
provided
the
State
is
authorized
to
administer
the
NPDES
Storm
Water
Program,
or
EPA
Regions.
At
the
Federal
level,
several
permitting
options
are
available;
depending
on
the
type
of
activity,
industrial
facilities
may
seek
coverage
under
an
individual
permit,
the
Baseline
Industrial
General
Permit,
or
the
Multi­
sector
General
Permit.
In
addition,
construction
activities
that
disturb
5
or
more
acres
of
land
are
regulated
under
the
Baseline
Construction
General
Permit.
Municipalities
serving
over
100,000
people
are
also
regulated,
but
on
an
individual
permit
basis.
Each
of
these
permitting
mechanisms
establishes
different
monitoring
programs.
Several
States
have
used
the
Federal
permits
as
models
for
their
permit
conditions.

Specific
monitoring
conditions
for
the
Federal
general
permits
are
detailed
in
the
following
documents:

°
"
Final
NPDES
General
Permits
for
Storm
Water
Discharges
Associated
With
Industrial
Activity,"
Federal
Register,
September
9,
1992.
(
Baseline
Industrial
General
Permit).

NPDES
Permit
Writers'
Manual
­
129
Chapter
7
Monitoring
and
Reporting
Conditions
°
"
Final
NPDES
General
Permits
for
Storm
Water
Discharges
from
Construction
Sites,"
Federal
Register,
September
9,
1992.
(
Baseline
Construction
General
Permit).

°
"
Final
NPDES
Storm
Water
Multi­
Sector
General
Permit
for
Industrial
Activities,"
Federal
Register,
September
9,
1992.
(
Multi­
Sector
General
Permit).

Monitoring
Combined
Sewer
Overflows
and
Sanitary
Sewer
Overflows
EPA's
CSO
Control
Policy
(
59
FR
18688)
requires
monitoring
to
characterize
the
combined
sewer
system,
assist
in
developing
the
Long­
Term
Control
Plan
(
LTCP),

and
illustrate
compliance
with
permit
requirements.
Monitoring
as
part
of
the
nine
minimum
controls
(
NMC)
is
done
to
develop
an
initial
system
characterization
and
includes
analyzing
existing
data
on
precipitation
events,
on
the
combined
sewer
system
and
CSOs,
on
water
quality,
and
conducting
field
inspections.
As
part
of
the
LTCP,
a
permittee
is
required
to
develop
a
more
complete
characterization
of
the
sewer
system
through
monitoring
and
modeling.
Finally,
to
illustrate
compliance
with
the
permit
requirements,
the
permittee
is
required
to
conduct
a
post­
construction
compliance
monitoring
program.
Specific
monitoring
requirements
of
this
postconstruction
compliance
monitoring
program
will
be
unique
to
each
permittee's
LTCP
and
should
be
established
as
specific
monitoring
conditions
in
the
individual
NPDES
permit.
These
monitoring
conditions
should
require
monitoring
of
a
representative
number
of
CSOs
for
a
representative
number
of
wet
weather
events
for
certain
key
parameters
along
with
ambient
water
quality
monitoring
to
ascertain
attainment
with
water
quality
standards.
EPA
is
currently
preparing
eight
guidance
manuals
on
various
aspects
of
the
CSO
Control
Policy,
including
one
on
monitoring,
Combined
Sewer
Overflows:
Guidance
for
Monitoring
and
Modeling
(
draft).
37
A
facility's
permit
may
also
contain
monitoring
requirements
for
sanitary
sewer
overflows
(
SSOs).
These
would
be
developed
on
a
case­
by­
case
basis.

37USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Monitoring
and
Modeling.
(
DRAFT).
EPA­
832/
R­
95­
005.

130
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
Whole
Effluent
Toxicity
Monitoring
The
use
of
whole
effluent
toxicity
(
WET)
testing
to
evaluate
the
toxicity
in
a
receiving
stream
was
discussed
in
Chapter
6.
The
biomonitoring
test
procedures
were
promulgated
in
40
CFR
Part
136
on
October
16,
1995
(
60
FR
53529).
WET
monitoring
conditions
included
in
permits
should
specify
the
particular
biomonitoring
test
to
be
used,
the
test
species,
required
test
endpoint,
and
QA/
QC
procedures.
EPA
has
published
recommended
toxicity
test
protocols
in
four
manuals:

°
Methods
for
Measuring
the
Acute
Toxicity
of
Effluents
and
Receiving
Waters
to
Freshwater
and
Marine
Organisms.
38
°
Short­
Term
Methods
for
Estimating
the
Chronic
Toxicity
of
Effluents
and
Receiving
Waters
to
Marine
and
Estuarine
Organisms.
39
°
Short­
Term
Methods
for
Estimating
the
Chronic
Toxicity
of
Effluents
and
Receiving
Waters
to
Freshwater
Organisms.
40
°
NPDES
Compliance
Monitoring
Inspector
Training:
Biomonitoring.
41
Samples
for
WET
may
be
composite
or
grab
samples.
Twenty­
four
hour
composite
samples
are
suggested
except
when
(
1)
the
effluent
is
expected
to
be
more
toxic
at
a
certain
time
of
day;
(
2)
toxicity
may
be
diluted
during
compositing;
and
(
3)
the
size
of
the
sample
needed
exceeds
the
composite
sampler
volume
(
e.
g.,
5
gallons).

WET
tests
are
relatively
expensive
(
see
Exhibit
7­
3
on
costs).
Therefore
the
test
frequency
should
be
related
to
the
probability
of
any
discharger
having
whole
38USEPA
(
1991).
Methods
for
Measuring
the
Acute
Toxicity
of
Effluents
and
Receiving
Waters
to
Freshwater
and
Marine
Organisms
39USEPA
(
1991).
Short­
Term
Methods
for
Estimating
the
Chronic
Toxicity
of
Effluents
and
Receiving
Waters
to
Marine
and
Estuarine
Organisms.
EPA­
600/
4­
91­
003.
Environmental
Monitoring
and
Support
Laboratory.

40USEPA
(
1991).
Short­
Term
Methods
for
Estimating
the
Chronic
Toxicity
of
Effluents
and
Receiving
Waters
to
Freshwater
Organisms,
Third
Edition.
EPA­
600/
4­
91­
002.
Environmental
Monitoring
and
Support
Laboratory.

41USEPA
(
1990).
NPDES
Compliance
Monitoring
Inspector
Training:
Biomonitoring.
Office
of
Water.

NPDES
Permit
Writers'
Manual
­
131
Chapter
7
Monitoring
and
Reporting
Conditions
effluent
toxicity.
Samples
should
be
evenly
spaced
throughout
the
year
so
that
seasonal
variability
can
be
ascertained.

Municipal
Sludge
Monitoring
The
purpose
of
monitoring
municipal
sludge
is
to
ensure
safe
use
or
disposal.

The
40
CFR
Part
503
sludge
regulations
require
monitoring
of
sewage
sludge
that
is
applied
to
land,
placed
on
a
surface
disposal
site,
or
incinerated.
The
frequency
of
monitoring
is
based
on
the
annual
amount
of
sludge
that
is
used
or
disposed
by
these
methods.
POTWs
that
provide
the
sewage
sludge
to
another
party
for
further
treatment
(
such
as
composting)
must
provide
that
party
with
the
information
necessary
to
comply
with
40
CFR
Part
503.
Sewage
sludge
disposed
of
in
a
municipal
solid
waste
landfill
unit
must
meet
the
requirements
in
40
CFR
Part
258,
which
is
the
criteria
for
municipal
solid
waste
landfills.

Exhibit
7­
4
shows
the
minimum
monitoring
requirements
for
sewage
sludge
prior
to
use
and
disposal
established
in
40
CFR
Part
503.
More
frequent
monitoring
for
any
of
the
required
or
recommended
parameters
is
appropriate
when
the
POTW:

°
Influent
load
of
toxics
or
organic
solids
is
highly
variable
°
Has
a
significant
industrial
load
°
Has
a
history
of
process
upsets
due
to
toxics,
or
of
adverse
environmental
impacts
due
to
sludge
use
or
disposal
activities.

The
sampling
and
analysis
methods
specified
in
40
CFR
§
503.8
should
be
followed
for
monitoring
the
required
parameters.
In
the
absence
of
any
specific
methods
in
40
CFR
Part
503,
guidance
on
appropriate
methods
is
contained
in
Part
503
Implementation
Guidance,
42
Control
of
Pathogens
and
Vector
Attraction
in
Sewage
Sludge,
43
and
POTW
Sludge
Sampling
and
Analysis
Guidance
Document.
44
42USEPA
(
1995).
Part
503
Implementation
Guidance.
EPA
833­
R­
95­
001.
Office
of
Water.

43USEPA
(
1992).
Control
of
Pathogens
and
Vector
Attraction
in
Sewage
Sludge.
EPA­
625/
R­
92­
013.
Office
of
Research
and
Development.

44USEPA
(
1989).
POTW
Sludge
Sampling
and
Analysis
Guidance
Document.
Office
of
Water,
Permits
Division.

132
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
EXHIBIT
7­
4
Minimum
Requirements
for
Sewage
Sludge
Monitoring,
Based
on
Method
of
Sludge
Use
or
Disposal
Method
Monitoring
Requirements
Frequency
Citation
Land
Application
(
1)
Sludge
weight
and
%
total
solids
Metals:
As,
Cd,
Cu,
Pb,
Hg,
Mo,
Ni,
Se,
and
Zn
Pathogen
Reduction
Vector
Attraction
Reduction
(
1)
0<
and
<
290*,
annually
290<
and
<
1,500,
quarterly
1,500<
and
<
15,000,
bimonthly
15,000
=
or
<,
monthly
40
CFR
Part
503.16
Co­
disposal
in
Municipal
Solid
Waste
Landfill
(
1)
Sludge
weight
and
%
total
solids
(
2)
Passes
Paint­
Filter
Liquid
Test
(
3)
Suitability
of
sludge
used
as
cover
(
4)
Characterize
in
accordance
with
hazardous
waste
rules
(
1),
(
2),
(
3),
and
(
4)
Monitoring
requirements
or
frequency
not
specified
by
40
CFR
Part
503.
Determined
by
local
health
authority
or
landfill
owner/
operator
40
CFR
Part
258.28
Surface
Disposal:
Lined
Sites
with
leachate
collection
and
Unlined
Sites
(
1)
Sludge
weight
and
%
total
solids
Pathogen
Reduction
Vector
Attraction
Reduction
Metals:
As,
Cr,
Ni
(
Unlined
Sites
Only)
(
2)
Methane
gas
(
1)
Based
on
sludge
quantity
(
as
above)
(
2)
Continuously
40
CFR
Part
503.26
Incineration
(
1)
Sludge
weight
and
%
total
solids
Metals:
As,
Cd,
Cr,
Pb,
and
Ni
(
2)
Be
and
Hg
(
Nat.
Emissions
Standards)
(
3)
THC
or
CO,
O
2,
moisture,
combustion
temperatures
(
4)
Air
pollution
control
device
operating
parameters
(
1)
Based
on
sludge
quantity
(
as
above)
(
2)
As
required
by
subparts
C
and
E
of
40
CFR
Part
61
as
may
be
specified
by
permitting
authority
(
local
air
authority)
(
3)
Continuously
(
4)
Daily
40
CFR
Part
503.46
Notes:
1.
Monitoring
frequencies
required
under
40
CFR
Part
503
may
be
reduced
after
2
years
of
monitoring,
but
in
no
case
shall
be
less
than
once
per
year.

2.
A
successful
land
application
program
may
necessitate
sampling
for
other
constituents
of
concern
(
such
as
nitrogen)
in
determining
appropriate
agronomic
rates.
This
will
be
determined
by
the
permit
writer.

*
Dry
weight
of
sludge
in
metric
tons
per
year.

NPDES
Permit
Writers'
Manual
­
133
Chapter
7
Monitoring
and
Reporting
Conditions
7.2
Reporting
and
Recordkeeping
Requirements
The
NPDES
regulations
at
40
CFR
§
§
122.41(
l)(
4)(
j)
and
(
l)
require
the
permittee
to
keep
records
and
periodically
report
on
monitoring
activities.
Discharge
Monitoring
Reports
(
DMRs)
(
see
form
in
Exhibit
7­
5)
must
be
used
by
permittees
to
report
self­
monitoring
data.
Data
reported
include
both
data
required
by
the
permit
and
any
additional
data
the
permittee
has
collected
consistent
with
permit
requirements.
All
facilities
are
required
to
submit
reports
(
on
discharges
and
sludge
use
or
disposal)
at
least
annually
per
40
CFR
§
122.44(
i)(
2).
POTWs
with
pretreatment
programs
are
required
to
submit
a
pretreatment
report
at
least
annually
per
Section
403.12(
i).
However,
the
NPDES
regulation
states
that
monitoring
frequency
and
reporting
should
be
dependent
on
the
nature
and
effect
of
the
discharge/
sludge
use
or
disposal.
Thus,
the
permit
writer
can
require
more
frequent
than
annual
reporting.

Records
must
be
kept
by
the
permittee
for
at
least
3
years
and
this
time
may
be
extended
by
the
Director
upon
request.
An
exception
is
for
sewage
sludge
records
which
must
be
kept
5
years
or
longer
if
required
by
40
CFR
Part
503.
The
permit
writer
should
designate
where
records
should
be
located.
Monitoring
records
include:

°
Date,
place,
time
°
Name
of
sampler
°
Date
of
analysis
°
Name
of
analyst
°
Analytical
methods
used
°
Analytical
results.

According
to
40
CFR
§
122.41(
j),
monitoring
records
must
be
representative
of
the
discharge.
Records
which
must
be
retained
include
continuous
strip
chart
recordings
calibration
data,
copies
of
all
reports
for
the
permit,
and
copies
of
all
data
used
to
compile
reports
and
applications.
Sludge
regulations
under
40
CFR
§
§
503.17,

503.27,
and
503.47
establish
recordkeeping
requirements
that
vary
depending
on
the
use
and
disposal
method
for
the
sludge.
The
same
recordkeeping
requirements
should
be
applied
to
other
sludge
monitoring
parameters
not
regulated
by
the
40
CFR
Part
503
rule.

134
­
NPDES
Permit
Writers'
Manual
Monitoring
and
Reporting
Conditions
Chapter
7
EXHIBIT
7­
5
Discharge
Monitoring
Report
(
DMR)

EXHIBIT
7­
5.

Discharge
Monitoring
Report
(
DMR)

NPDES
Permit
Writers'
Manual
­
135
Chapter
11
Administrative
Process
Previous
discussions
in
this
manual
focused
on
the
process
of
developing
NPDES
permit
conditions
and
effluent
limits.
This
chapter
describes
the
administrative
process
that
is
associated
with
the
issuance
of
a
NPDES
permit.
Exhibit
11­
1
provides
a
flow
diagram
of
the
NPDES
permit
administrative
process.
In
general,
the
administrative
process
includes:

°
Documenting
all
permit
decisions
°
Coordinating
EPA
and
State
review
of
the
draft
permit
°
Providing
public
notice,
conducting
hearings
(
if
appropriate),
and
responding
to
comments
°
Defending
the
permit
and
modifying
it
(
if
necessary)
after
issuance.

Note
that
Exhibit
11­
1
provides
the
general
framework
for
both
EPA
and
State
NPDES
permit
administration.
State
requirements
need
not
be
identical
to
Federal
regulatory
requirements,
provided
they
are
as
stringent.
Therefore,
some
delegated
States
may
have
slightly
different
processes
for
developing
and
issuing
NPDES
permits.
In
addition,
the
evidentiary
hearing
and
appeal
process
presented
depicts
EPA
procedure.
State
procedures
for
NPDES
permit
hearings
and
appeals
may
vary
according
to
State
law.

NPDES
Permit
Writers'
Manual
­
191
Chapter
11
Administrative
Process
Develop
draft
permit
limits
and
conditions
Prepare
fact
sheet
(
or
statement
of
basis)

Prepare
administrative
record
(
EPA
only)

EPA/
State
review
of
draft
permit
and
fact
sheet
(
or
statement
of
basis)

No
EPA
Comment/
State
401
Certification
Public
notice
(
opportunity
for
public
comment)
Significant,
Widespread,
Public
Interest
Prepare
final
permit,
fact
sheet,
and
admin.
record
Public
Hearing
Issue
final
permit
Significant
EPA
Comments/
No
State
401
certification
100D­
01
Opportunity
for
Informal
appeal
to
the
Environmental
Appeals
Board
Opportunity
for
Informal
appeal
to
the
Environmental
Appeals
Board
Request
for
Evidentiary
Hearing
Formal
appeal
to
Environmental
Appeals
Board
Environmental
Appeals
Board
Decision
Final
Agency
Action
No
Appeal
No
Appeal
Denied
Granted
Hold
Hearing
EXHIBIT
11­
1
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Permitting
Administrative
Process
192
­
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Chapter
11
11.1
Documentation
For
Development
of
the
Draft
Permit
When
the
permit
is
issued,
the
fact
sheet
and
supporting
documentation
(
administrative
record)
are
the
primary
support
for
defending
the
permit
in
administrative
appeals
and
evidentiary
hearings.
The
process
of
documenting
the
permit
requires
the
permit
writer
to
be
organized
and
logical
throughout
the
permit
development
process.
Some
of
the
content
of
the
fact
sheet
and
administrative
record
is
directed
by
Federal
and
State
regulation
and
the
rest
is
dictated
by
good
project
management.
Permit
writers
should
recognize
the
importance
of:

°
Ensuring
development
of
a
thorough
permit
in
a
logical
fashion
°
Meeting
legal
requirements
for
preparation
of
an
administrative
record,
fact
sheet,
and
statement
of
basis
°
Helping
to
substantiate
permit
decisions
and
provide
a
sound
basis
in
case
challenges
are
made
to
the
derivation
of
permit
terms,
conditions,
and
limitations
°
Establishing
a
permanent
record
of
the
basis
of
the
permit
for
use
in
future
permit
actions.

The
following
sections
describe
the
requirements
pertaining
to
the
development
of
permit
documentation,
particularly
the
administrative
record
and
the
fact
sheet.

11.1.1
Administrative
Record
The
administrative
record
is
the
foundation
for
issuing
permits.
If
EPA
is
the
issuer,
the
contents
of
the
administrative
record
are
prescribed
by
regulation
(
see
40
CFR
§
§
124.9
and
124.18).
All
supporting
materials
must
be
made
available
to
the
public,
whether
a
State,
Territory,
Tribe
or
EPA
issues
the
permit.
The
importance
of
maintaining
the
permit
records
in
a
neat,
orderly,
complete,
and
retrievable
form
cannot
be
over
emphasized.
The
record
allows
personnel
from
the
permitting
agency
to
reconstruct
the
justification
for
a
given
permit.
It
also
must
be
made
available
to
the
public
at
any
time
and
may
be
examined
during
the
public
comment
period
and
any
subsequent
public
hearing.

The
administrative
record
for
a
draft
permit
consists,
at
a
minimum,
of
certain
specific
documents
as
shown
in
Exhibit
11­
2.
Materials
that
are
readily
available
in
the
permit
issuing
office
or
published
material
that
is
generally
available,
does
not
NPDES
Permit
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Chapter
11
Administrative
Process
need
to
be
physically
included
with
the
record
as
long
as
it
is
specifically
referred
to
in
EXHIBIT
11­
2
Elements
of
the
Draft
NPDES
Permit
Administrative
Record
°
Application
and
supporting
data
°
Draft
permit
°
Statement
of
basis
or
fact
sheet
°
All
items
cited
in
the
statement
of
basis
or
fact
sheet,
including
calculations
used
to
derive
the
permit
limits
°
All
other
items
in
the
supporting
file
°
For
new
sources,
any
environmental
assessment,
the
draft/
final
environmental
impact
statement
(
EIS),
or
other
such
background
information,
such
as
a
Findings
of
No
Significant
Impact
(
only
applies
if
EPA
issues
the
permit).

the
fact
sheet
or
statement
of
basis.
If
EPA
issues
new
source
draft
permits,
the
administrative
record
should
include
any
EIS
or
environmental
assessment
performed
in
accordance
with
40
CFR
§
122.29(
c).

The
administrative
record
should
include
all
meeting
reports
and
correspondence
with
the
applicant
and
correspondence
with
other
regulatory
agency
personnel.
In
addition,
trip
reports
and
telephone
memos
should
be
included
in
the
record.
All
correspondence,
notes,
and
calculations
should
indicate
the
date
and
the
name
of
the
writer,
as
well
as
all
other
persons
involved.
Since
correspondence
is
subject
to
public
scrutiny,
references
or
comments
that
do
not
serve
an
objective
purpose
should
be
avoided.
Finally,
presentation
of
calculations
and
documentation
of
decisions
should
be
organized
in
such
a
way
that
they
can
be
reconstructed
and
the
logic
supporting
the
calculation
or
decisions
can
easily
be
found.
The
administrative
record
for
the
final
permit
consists
of
the
items
in
Exhibit
11­
3.

11.1.2
Fact
Sheets
and
Statements
of
Basis
A
fact
sheet
is
a
document
that
briefly
sets
forth
the
principle
facts
and
the
significant
factual,
legal,
methodological,
and
policy
questions
considered
in
preparing
the
draft
permit.
When
the
permit
is
in
the
draft
stage,
the
fact
sheet
and
supporting
documentation
serve
to
explain
to
the
permittee
and
the
general
public
the
rationale
and
assumptions
used
in
deriving
the
limits.

194
­
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Manual
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11
EXHIBIT
11­
3
Elements
of
the
Administrative
Records
for
a
Final
Permit
°
All
elements
for
the
draft
permit
administrative
record
(
see
Exhibit
11­
2)

°
All
comments
received
during
the
comment
period
°
The
tape
or
transcript
of
any
public
hearing
°
Any
materials
submitted
at
a
hearing
°
Responses
to
comments
°
For
NPDES
new
source
permits,
the
draft
or
final
EIS
°
The
final
permit.

The
NPDES
regulations
set
forth
in
40
CFR
§
124.8(
a)
require
that
every
EPA
and
State­
issued
permit
must
be
accompanied
by
a
fact
sheet
if
the
permit:

°
Involves
a
major
facility
or
activity
°
Incorporates
a
variance
or
requires
an
explanation
under
40
CFR
§
124.56(
b)
(
toxic
pollutants,
internal
waste
stream,
and
indicator
pollutants
and
for
privately
owned
waste
treatment
facilities)

°
Is
a
NPDES
general
permit
°
Is
subject
to
widespread
public
interest
(
see
40
CFR
§
124.8)

°
Is
a
Class
1
sludge
management
facility
°
Includes
a
sewage
sludge
land
application
plan.

EPA
permit
writers
are
required
to
prepare
a
statement
of
basis
for
all
permits
that
do
not
merit
the
detail
of
a
fact
sheet.
Such
statements
briefly
describe
the
derivation
of
the
effluent
limits
and
the
reasons
for
special
conditions
(
see
40
CFR
§
124.7).
However,
a
prudent
permit
writer
will
develop
a
fact
sheet
for
any
permit
that
required
complex
calculations
or
special
conditions.
This
will
be
particularly
true
for
permit
conditions
based
on
BPJ.

With
a
well­
documented
rationale
for
all
decisions,
much
of
the
work
in
reissuing
a
permit
in
the
future
will
be
done.
This
will
avoid
any
conjecture
and
guessing
concerning
the
development
of
any
conditions
that
are
being
carried
forward
from
the
expired
permit
to
the
next
permit.
This
is
also
true
if
a
modification
is
initiated
during
the
life
of
the
permit.
A
permit
rationale
can
be
as
short
as
two
to
three
pages
for
a
relatively
simple
permit
or
as
long
as
20
to
100
pages
for
an
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Chapter
11
Administrative
Process
extremely
complicated
permit
(
e.
g.,
several
discharge
points,
many
BPJ
determinations).
The
required
contents
of
a
fact
sheet,
as
specified
in
40
CFR
§
§
124.8
and
124.56,
include
the
items
listed
in
Exhibit
11­
4.

A
detailed
discussion
of
the
development
of
permit
limits
for
each
pollutant
EXHIBIT
11­
4
Required
Contents
of
a
Fact
Sheet
°
A
brief
description
of
the
type
of
facility
or
activity
that
is
being
regulated
by
the
NPDES
permit
°
The
type
and
quantity
of
pollutants
discharged
°
A
brief
summary
of
the
basis
for
the
draft
permit
conditions,
including
references
to
the
applicable
statutory
or
regulatory
provisions
°
Name
and
telephone
number
of
person
to
contact
for
additional
information
°
Provisions
satisfying
the
requirements
of
40
CFR
§
124.56:

 
Explanation
of
derivation
of
effluent
limitations
 
Explanation
of
any
conditions
applicable
to
toxic,
internal
waste
streams,
or
indicator
pollutants
 
A
sketch
or
detailed
description
of
the
location
of
the
discharge
 
For
EPA
issued
permits,
the
requirements
of
any
State
certification
°
For
every
permit
to
be
issued
to
a
treatment
works
owned
by
a
person
other
than
a
State
or
municipality,
an
explanation
of
the
decision
to
regulate
the
users
under
a
separate
permit
°
For
every
permit
that
includes
a
sewage
sludge
land
application
plan,
a
brief
description
of
how
each
of
the
required
elements
of
the
land
application
plan
are
addressed
in
the
permit
°
If
applicable,
reasons
why
any
requested
variances
do
not
appear
justified
°
A
description
of
the
procedures
for
reaching
a
final
decision
on
the
draft
permit,
including:

 
The
dates
of
the
public
comment
period
and
the
address
 
Procedures
for
requesting
a
hearing
 
Other
procedures
for
public
participation.

should
be
included
in
the
fact
sheet.
For
some
permits,
a
considerable
amount
of
time
is
spent
within
the
permitting
agency
debating
a
permit
issue
that
then
becomes
an
assumption
upon
which
the
permit
conditions
are
based.
Documenting
the
196
­
NPDES
Permit
Writers'
Manual
Administrative
Process
Chapter
11
decision
process
may
prevent
a
repeat
of
the
debate
in
5
years
when
the
permit
is
up
for
reissuance.
For
each
pollutant
the
following
information
is
necessary:

°
Calculations
and
assumptions
 
Production
 
Flow
°
Type
of
limitations
(
i.
e.,
effluent
guideline­,
water
quality­,
or
BPJ­
based)

°
Whether
the
effluent
guidelines
used
were
BPT,
BCT,
or
BAT
°
The
water
quality
standards
or
criteria
used
°
Whether
any
pollutants
were
indicators
for
other
pollutants
°
Citations
to
appropriate
wasteload
allocation
studies,
guidance
documents,
other
references.

Often,
it
is
as
important
to
keep
a
record
of
items
that
were
not
included
in
the
draft
permit,
such
as
the
following:

°
Why
was
BPJ
or
effluent
guidelines
used
instead
of
water
quality­
based
limitations
(
i.
e.,
were
the
limitations
checked
to
see
that
water
quality
considerations
did
not
govern
the
setting
of
permit
limits)?

°
Why
was
biomonitoring
not
included?

°
Why
were
pollutants
that
were
reported
as
present
in
the
permit
application
not
specifically
limited
in
the
permit?

°
Why
is
a
previously
limited
pollutant
no
longer
limited
in
the
draft
permit?

Finally,
the
fact
sheet
should
address
the
logistics
of
the
permit
issuance
process
including
the
comment
period
begin
and
end
dates,
procedures
for
requesting
a
hearing,
and
the
public
involvement
in
the
final
decision.

11.2
Items
to
Address
Prior
to
Issuance
of
a
Final
Permit
This
section
describes
the
public
participation
activities
that
must
be
conducted
in
the
permit
issuance
process.
These
include
providing
public
notices,
collecting
and
responding
to
public
comments,
and
holding
public
hearings
as
necessary.

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Chapter
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11.2.1
Public
Notice
The
public
notice
is
the
vehicle
for
informing
all
interested
parties
and
members
of
the
general
public
of
the
contents
of
a
draft
NPDES
permit
or
of
other
significant
actions
with
respect
to
a
NPDES
permit
or
permit
application.
The
basic
intent
of
this
requirement
is
to
ensure
that
all
interested
parties
have
an
opportunity
to
comment
on
significant
actions
of
the
permitting
agency
with
respect
to
a
permit
application
or
a
permit.
The
exact
scope,
required
contents,
and
methods
for
effecting
public
notices
may
be
found
in
40
CFR
§
124.10.

The
NPDES
permit­
related
actions
that
must
receive
public
notice
are
shown
in
Exhibit
11­
5.

The
permit
writer
should
be
primarily
concerned
with
the
first
three
items
in
EXHIBIT
11­
5
Actions
That
Must
Receive
Public
Notice
°
Tentative
denial
of
an
NPDES
permit
application
(
not
necessarily
applicable
to
State
programs)

°
Preparation
of
a
draft
NPDES
permit,
including
a
proposal
to
terminate
a
permit
°
Scheduling
of
a
public
hearing
°
Granting
of
an
evidentiary
appeal
of
an
EPA­
issued
permit
under
40
CFR
§
124.74
°
Formal
appeal
of
permit
°
New
Source
Determinations
(
EPA
only)

Exhibit
11­
5.
It
is
important
to
note
that
no
public
notice
is
required
when
a
request
for
a
permit
modification,
revocation,
reissuance,
or
termination
is
denied.

Public
notice
of
the
various
NPDES­
related
activities
is
provided
by
the
following
methods:

°
For
major
permits,
publication
of
a
notice
in
daily
or
weekly
newspaper
within
the
area
affected
by
the
facility
or
activity.
In
addition,
for
general
permits
issued
by
EPA,
publication
in
the
Federal
Register
is
required.

198
­
NPDES
Permit
Writers'
Manual
Administrative
Process
Chapter
11
°
Direct
mailing
to
various
interested
parties.
This
mailing
list
should
include
the
following:

 
The
applicant
 
Any
interested
parties
on
the
mailing
list
 
Any
other
agency
that
is
required
to
issue
a
Resource
Conservation
and
Recovery
Act,
Underground
Injection
Control,
Corps
of
Engineers,
or
PSD
permit
for
the
same
facility
 
All
appropriate
government
authorities
(
e.
g.,
United
States
Fish
and
Wildlife
Services,
National
Marine
Fisheries
Service,
neighboring
States)
 
Users
identified
in
the
permit
application
of
a
POTW.

A
public
notice
must
contain
the
information
shown
in
Exhibit
11­
6.

Public
notice
of
the
preparation
of
the
draft
permit
(
including
a
notice
of
intent
to
EXHIBIT
11­
6
Contents
of
the
Public
Notice
°
Name
and
address
of
the
office
processing
the
permit
action
°
Name
and
address
of
the
permittee
or
applicant
and,
if
different,
of
the
facility
regulated
by
the
permit
°
A
brief
description
of
the
business
conducted
at
the
facility
°
Name,
address,
and
telephone
number
of
a
contact
from
whom
interested
persons
can
obtain
additional
information
°
A
brief
description
of
the
comment
procedures
required
°
For
EPA­
issued
permits,
the
location
and
availability
of
the
administrative
record
°
Any
additional
information
considered
necessary.

deny
a
permit
application)
must
allow
at
least
30
days
for
public
comment.
The
draft
permit
is
usually
submitted
for
public
notice
after
it
has
undergone
internal
review
by
the
regulatory
agency
that
is
issuing
the
permit.
State/
Tribal
issued
permits
will
typically
undergo
public
notice
after
EPA
has
reviewed
and
commented
on
the
draft
permit.
In
the
special
case
of
those
EPA­
issued
permits
that
require
an
environmental
impact
statement
(
EIS),
public
notice
is
not
given
until
after
a
draft
EIS
is
issued.

11.2.2
Public
Comments
Public
notice
of
a
draft
permit
elicits
comments
from
concerned
individuals
or
agencies.
Frequently,
such
comments
are
simply
requests
for
additional
information.

However,
some
comments
are
of
a
substantive
nature
and
suggest
modifications
to
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Permit
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199
Chapter
11
Administrative
Process
the
draft
permit
or
indicate
that
the
draft
permit
is
inappropriate
for
various
reasons.
In
such
cases,
those
parties
providing
comments
must
submit
all
reasonable
arguments
and
factual
material
in
support
of
their
positions.
If
the
approach
is
technically
correct
and
clearly
stated
in
the
fact
sheet,
it
will
be
difficult
for
commenters
to
find
fault
with
the
permit.
Commenters
may
always
suggest
alternatives,
however.
In
addition,
an
interested
party
may
also
request
a
public
hearing.

To
the
extent
possible,
it
is
desirable
to
respond
to
all
public
comments
as
quickly
as
possible.
In
some
cases
it
may
be
possible
to
diffuse
a
potentially
controversial
situation
by
providing
further
explanation
of
permit
terms
and
conditions.

It
is
also
good
public
practice
to
inform
parties
who
provide
public
comments
that
their
comments
have
been
received
and
are
being
considered.

The
permitting
agency
is
obliged
to
respond
to
all
significant
comments
(
in
accordance
with
40
CFR
§
124.17)
at
the
time
a
final
permit
decision
is
reached
(
in
the
case
of
EPA­
issued
permits)
or
at
the
same
time
a
final
permit
is
actually
issued
(
in
the
case
of
State­
issued
permits).
The
response
should
incorporate
the
following
elements:

°
Changes
in
any
of
the
provisions
of
the
draft
permit
and
the
reasons
for
the
changes
°
Description
and
response
to
all
significant
comments
on
the
draft
permit
raised
during
the
public
comment
period
or
during
any
hearing.

In
the
event
that
any
information
submitted
during
the
public
comment
period
raises
substantial
new
questions
about
the
draft
permit,
one
of
the
following
actions
may
occur:

°
A
new
draft
permit
with
revised
fact
sheet
or
statement
of
basis
is
prepared.

°
A
final
permit
with
necessary
changes
explained
is
issued.

°
The
comment
period
is
reopened
but
is
limited
only
to
new
findings.

If
any
of
these
actions
are
taken,
a
new
public
notice,
as
described
earlier,
must
be
given.

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11.2.3
Public
Hearing
A
public
hearing
may
be
requested
in
writing
by
any
interested
party.
The
request
should
state
the
nature
of
the
issues
proposed
to
be
raised
during
the
hearing.
However,
a
request
for
a
hearing
does
not
automatically
necessitate
that
a
hearing
be
held.
A
public
hearing
should
be
held
when
there
is
a
significant
amount
of
interest
expressed
during
the
30­
day
public
comment
period
or
when
it
is
necessary
to
clarify
the
issues
involved
in
the
permit
decision.

Thus,
the
decision
of
whether
or
not
to
hold
a
public
hearing
is
actually
a
judgment
call.
Such
decisions
are
usually
made
by
someone
other
than
the
permit
writer.
However,
the
permit
writer
will
be
responsible
for
ensuring
that
all
of
the
factual
information
in
support
of
the
draft
permit
is
well
documented.

Public
notice
of
a
public
hearing
must
be
given
at
least
30
days
prior
to
the
public
meeting
(
public
notice
of
the
hearing
may
be
given
at
the
same
time
as
public
notice
of
the
draft
permit
and
the
two
notices
may
be
combined).
Scheduling
a
hearing
automatically
extends
the
comment
period
until
at
least
the
close
of
the
hearing
[
40
CFR
§
124.12(
c)].

The
public
notice
of
the
hearing
should
contain
the
following
information:

°
Brief
description
of
the
nature
and
purpose
of
the
hearing,
including
the
applicable
rules
and
procedures
°
Reference
to
the
dates
of
any
other
public
notices
relating
to
the
permit
°
Date,
time,
and
place
of
the
hearing.

A
presiding
officer
is
responsible
for
the
hearing's
scheduling
and
orderly
conduct.
Anyone
may
submit
written
or
oral
comments
concerning
the
draft
permit
at
the
hearing.
The
presiding
officer
should
set
reasonable
time
limits
for
oral
statements.
The
public
comment
period
may
be
extended
by
so
stating
during
the
hearing.
It
should
be
noted
that
a
transcript
or
recording
of
the
hearing
must
be
available
to
interested
persons.

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11.2.4
State/
Tribal
Roles
in
Reviewing
Draft
Permit
State/
Tribal
issued
draft
permits
must
be
submitted
to
EPA
for
review
if
they
relate
to:

°
Discharges
into
the
territorial
seas
°
Discharges
that
may
affect
waters
of
a
State
other
than
the
one
in
which
the
discharge
originates
°
General
permits
°
Discharges
from
a
POTW
with
a
daily
average
discharge
exceeding
1
million
gallons
per
day
°
Discharges
of
uncontaminated
cooling
water
with
a
daily
average
discharge
exceeding
500
million
gallons
per
day
°
Discharges
from
any
major
discharger
or
from
any
NPDES
primary
industrial
category
°
Discharges
of
from
other
sources
with
a
daily
average
discharge
exceeding
500,000
gallons
per
day
(
however,
EPA
may
waive
review
for
non­
process
wastewater),
and
°
Class
I
sludge
management
facilities.

Permits
issued
by
EPA
require
State/
Tribal
review
and
certification
under
Section
401
of
the
CWA.
Such
certification
ensures
that
the
permit
will
comply
with
applicable
Federal
CWA
standards
as
well
as
with
State
or
Tribal
water
quality
standards.
This
State/
Tribal
certification
also
ensures
that
State
and
Tribal
initiatives
or
policies
are
addressed
in
EPA­
issued
NPDES
permits,
and
functions
to
promote
consistency
between
State­
and
EPA­
issued
permits.

Under
CWA
Section
401(
a)(
1),
EPA
may
not
issue
a
permit
until
a
certification
is
granted
or
waived.
If
EPA
is
preparing
the
draft
permit,
State
certification
is
usually
accomplished
by
allowing
States
to
review
and
certify
the
application
prior
to
draft
permit
preparation.
Regulations
in
40
CFR
§
124.53
[
State
Certification]
and
§
124.54
[
Special
provisions
for
State
certification
and
concurrence
on
applications
for
section
CWA
301(
h)
variances]
describe
procedures
a
permit
writer
should
follow
to
obtain
State
or
Tribal
certification.
Under
40
CFR
§
124.53,
when
a
draft
permit
is
prepared
by
EPA,
but
State
certification
has
not
yet
been
granted,
EPA
must
send
the
State
a
copy
of
the
draft
permit
along
with
a
notice
requesting
State
certification.
If
the
State
does
not
respond
within
60
days,
the
State
is
deemed
to
have
waived
its
right
to
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certify.
If
the
State
chooses
to
certify
the
draft
permit,
the
State
may
only
require
changes
to
the
draft
permit
to
incorporate
more
stringent
State
laws.
If
the
State
requires
such
changes,
the
State
must
send
EPA
a
letter
justifying
the
changes
and
citing
State
regulations
that
support
the
changes.
When
a
permit
applicant
requests
a
CWA
Section
301(
h)
variance,
the
State
certification
process
is
very
similar
to
the
process
just
described
for
permit
applications
and
draft
permits
(
refer
to
Section
40
CFR
§
124.54).

11.2.5
Schedule
for
Final
Permit
Issuance
The
final
permit
may
be
issued
after
the
close
of
the
public
notice
period
and
after
State/
Tribal
certification
has
been
received
(
for
permits
issued
by
EPA).
The
public
notice
period
includes:

°
A
30­
day
period
that
gives
notice
of
intent
to
issue
or
deny
the
permit
°
A
30­
day
period
advertising
a
public
hearing
(
if
applicable)

°
Any
extensions
or
reopening
of
the
comment
period.

Final
EPA
permit
decisions
are
effective
immediately
upon
issuance
unless
comments
request
changes
in
the
draft
permit,
in
which
case
the
effective
date
of
the
permit
is
30
days
after
issuance
(
or
a
later
date
if
specified
in
the
permit).
As
discussed
earlier,
any
comments
that
are
received
must
be
answered
at
the
time
of
final
permit
issuance
(
in
the
case
of
NPDES
States
or
Tribes)
or
after
a
final
decision
is
reached
(
in
the
case
of
EPA).

11.3
Administrative
Actions
After
Final
Permit
Issuance
Once
the
final
permit
has
been
issued,
the
issuing
authority
should
integrate
the
permit
limitations
and
any
special
conditions
into
the
NPDES
tracking
system
(
i.
e.,
the
permit
compliance
system
(
PCS)).
This
will
ensure
that
the
facility's
performance
will
be
tracked
and
the
permitting
agency
will
be
alerted
to
the
need
for
corrective
action
in
the
event
of
violations
of
permit
limitations,
terms,
or
conditions.

After
final
permit
issuance,
interested
parties
have
other
opportunities
to
change
the
permit
thorough
permit
appeals,
major/
minor
permit
modifications,
permit
termination
or
permit
transfer.
These
administrative
procedures
are
described
below.

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Chapter
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11.3.1
Permit
Appeals
In
the
process
of
developing
a
draft
permit
and
during
the
public
notice
period,

the
permit
writer
should
carefully
consider
the
legitimate
concerns
of
the
permittee
as
well
as
the
concerns
of
any
third
party
who
may
have
an
interest
in
the
permit
terms
and
conditions.
However,
there
will
inevitably
be
situations
in
which
a
permit
is
issued
in
spite
of
the
objections
of
the
permittee
or
a
third
party.
In
such
instances,
the
permittee
or
an
interested
party
may
choose
to
legally
contest
or
appeal
the
NPDES
permit.

Various
mechanisms
are
available
to
resolve
legal
challenges
to
NPDES
permits.
In
the
case
of
EPA­
issued
permits,
the
administrative
procedure
involved
is
called
an
evidentiary
hearing.
Many
NPDES
States
and
Tribes
have
similar
administrative
procedures
designed
to
resolve
challenges
to
the
conditions
of
a
permit.

These
procedures
involve
hearings
presided
over
by
an
administrative
law
judge.
For
the
sake
of
convenience,
these
hearings
will
hereafter
be
referred
to
as
evidentiary
hearings.
They
will
naturally
be
known
by
different
names
in
different
State
or
Tribe
jurisdictions.
However,
permit
writers
will,
from
time­
to­
time,
be
involved
in
permit
appeals
and
will
need
to
address
the
types
of
issues
discussed
below.

Aside
from
preparation
of
the
administrative
record
and
notices,
the
permit
writer
may
not
be
concerned
with
procedural
matters
relating
to
evidentiary
hearings.

All
requests
for
evidentiary
hearings
are
coordinated
through
the
office
of
the
EPA
Regional
Counsel
or
the
appropriate
State
legal
personnel.
The
permit
writer's
first
involvement
with
the
hearing
process
will
come
as
a
result
of
designation
of
the
trial
staff
and
his/
her
role
will
be
limited
to
that
of
a
witness
and
technical
advisor
to
legal
counsel.

A
permit
writer
may
be
required
to
give
a
deposition
during
which
the
appellant
attorney
conducts
the
questioning
that
would
otherwise
occur
in
the
hearing.
The
deposition
is
transcribed
and
presented
as
evidence.
The
appellant
attorney
may
ask
some
of
the
same
questions
at
the
hearing.

To
prepare
for
a
deposition
and
testimony,
the
permit
writer
should
be
familiar
with
those
laws,
regulations,
and
policies
that
may
affect
the
permit.
The
permit
writer
should
be
thoroughly
familiar
with
the
technical
basis
for
the
permit
conditions.
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example,
if
the
effluent
limits
are
based
on
water
quality
requirements,
the
permit
writer
should
thoroughly
study
any
applicable
basin
plan
or
water
quality
simulation
used
to
develop
the
effluent
limits
and
be
prepared
to
defend
any
assumptions
inherent
in
the
plan
or
simulation.
If
BPJ
limits
are
based
on
proposed
effluent
guidelines,
it
will
be
necessary
to
carefully
review
not
only
the
guidelines
themselves
but
all
applicable
data,
including
the
development
document
for
the
specific
guidelines.

The
technical
defense
of
other
BPJ
requirements
is
much
more
difficult.
The
permit
writer
should
be
sure
that
(
1)
the
information
on
which
BPJ
limits
are
based
are
unimpeachable,
(
2)
the
limits
were
derived
from
the
data
in
a
logical
manner,
in
accordance
with
established
procedures,
and
(
3)
the
BPJ
limits
so
derived
are
technically
sound
and
meet
BCT
or
BAT
standards
for
economic
reasonableness.

As
technical
advisor
to
legal
counsel,
the
permit
writer's
most
important
function
is
to
develop
direct
testimony
in
support
of
contested
permit
conditions.
No
attempt
should
be
made
to
support
technically
indefensible
conditions.
Contested
permit
conditions
that
are
not
technically
defensible
and
are
not
based
on
any
legal
requirement
should
be
brought
to
counsel's
attention,
with
advice
that
EPA
or
the
State
agency
withdraw
those
conditions.

The
second
most
important
advisory
function
of
the
permit
writer
is
assisting
counsel
in
the
development
of
questions
for
cross­
examination
of
the
opposing
witnesses.
Questions
should
be
restricted
to
the
subject
material
covered
by
the
witness'
direct
testimony
and
should
be
designed
to
elicit
an
affirmative
or
negative
response,
rather
than
an
essay­
type
response.
If
a
question
must
be
phrased
in
such
a
way
that
the
witness
could
attempt
lengthy
explanations,
counsel
should
be
forewarned.

Finally,
the
permit
writer
should
remember
that
in
requesting
an
evidentiary
hearing,
the
permittee
has
declared
an
adversary
relationship
with
the
regulatory
agency,
and
the
permit
writer
must
therefore
refrain
from
discussions
about
the
case
without
prior
consultation
with
legal
counsel.
In
the
role
of
witness
and/
or
technical
advisor,
the
permit
writer
should:

°
Cultivate
credibility
°
Never
imply
or
admit
weakness
in
his
or
her
area
of
expertise
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Chapter
11
Administrative
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°
Never
attempt
to
testify
about
subjects
outside
his
or
her
area
of
expertise
°
Always
maintain
good
communication
with
counsel.

Where
the
permitee
is
granted
relief
at
the
evidentiary
hearing,
the
Administrative
Law
Judge
generally
will
order
appropriate
relief.
Where
a
request
for
an
evidentiary
hearing
is
denied,
the
permittee
may
file
a
notice
of
appeal
and
petition
for
review
with
the
Environmental
Appeals
Board
(
EAB),
which
may
or
may
not
grant
an
evidentiary
hearing
based
on
the
factual
and
legal
issues
alleged.
Similarly,
where
a
permittee
is
denied
relief
at
an
evidentiary
hearing,
the
permittee
may
appeal
to
the
EAB
to
overturn
the
hearing
decision.
Finally,
under
certain
circumstances
decisions
of
the
EAB
against
the
permittee
may
be
appealed
in
Federal
court.

11.3.2
Permit
Modification,
Revocation,
Termination,
and
Transfer
After
the
final
permit
is
issued,
the
permit
may
still
need
to
be
modified
or
revoked
prior
to
the
expiration
date.
Modifications
differ
from
revocations
and
reissuance.
In
a
permit
modification,
only
the
conditions
subject
to
change
are
reconsidered
while
all
other
permit
conditions
remain
in
effect.
Conversely,
the
entire
permit
may
be
reconsidered
when
it
is
revoked
and
reissued.
A
permit
modification
may
be
triggered
in
several
ways.
For
example,
a
representative
of
the
regulatory
agency
may
conduct
an
inspection
of
the
facility
that
indicated
a
need
for
the
modification
(
i.
e.,
the
improper
classification
of
an
industry),
or
information
submitted
by
the
permittee
may
suggest
the
need
for
a
change.
Of
course,
any
interested
person
may
request
that
a
permit
modification
be
made.

There
are
two
classifications
of
modifications:
major
and
minor.
From
a
procedural
standpoint,
they
differ
primarily
with
respect
to
the
public
notice
requirement.
Major
modifications
require
public
notice;
minor
modifications
do
not.

Virtually
all
modifications
that
result
in
less
stringent
conditions
must
be
treated
as
major
modifications,
with
provisions
for
public
notice
and
comment.
Generally
speaking,
a
permit
will
not
need
to
be
modified
during
the
term
of
the
permit
if
the
facility
can
fully
comply
with
permit
conditions.
Conditions
that
would
necessitate
a
major
modification
of
a
permit
are
described
in
40
CFR
§
122.62
and
shown
in
Exhibit
11­
7.

206
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Permit
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Chapter
11
EXHIBIT
11­
7
Conditions
Requiring
Major
Modification
°
Reopener
 
Conditions
in
the
permit
that
required
it
to
be
reopened
under
certain
circumstances.

°
Technical
Mistakes
 
To
correct
technical
mistakes
or
mistaken
interpretations
of
law
made
in
developing
the
permit
conditions.

°
Failure
to
Notify
 
Upon
failure
of
an
approved
State
to
notify
another
State
whose
waters
may
be
affected
by
a
discharge
from
the
approved
State.

°
Alterations
 
When
alterations
or
changes
in
operations
occur
that
justify
new
conditions
that
are
different
from
the
existing
permit.

°
New
Information
 
When
information
is
received
that
was
not
available
at
the
time
of
permit
issuance.

°
New
Regulations
 
When
standards
or
regulations
on
which
the
permit
was
based
have
been
changed
by
promulgation
of
amended
standards
or
regulations
or
by
judicial
decision.

°
Compliance
Schedules
for
Innovative
or
Alternative
Facilities
 
To
modify
the
compliance
schedule
in
light
of
the
additional
time
that
may
be
required
to
construct
this
type
of
facility;
or
when
good
cause
for
modification
of
a
compliance
schedule
exists,
such
as
an
Act
of
God,
strike,
or
flood.

°
Pretreatment
 
To
require
that
an
approved
program
be
implemented
or
to
change
the
schedule
for
program
development.

°
Failed
BPJ
Compliance
 
When
BPJ
technology
is
installed
and
properly
operated
and
maintained
but
the
permittee
is
unable
to
meet
its
limits,
the
limits
may
be
reduced
to
reflect
actual
removal;
but
in
no
case
may
they
be
less
than
the
guideline
limits.
If
BPJ
operation
and
maintenance
costs
are
totally
disproportionate
to
the
costs
considered
in
a
subsequent
guideline,
the
permittee
may
be
allowed
to
backslide
to
the
guideline
limits.

°
Non­
Limited
Pollutants
 
When
the
level
of
discharge
of
any
pollutant
that
is
not
limited
in
the
permit
exceeds
the
level
that
can
be
achieved
by
the
technology­
based
treatment
requirements
appropriate
to
the
permit.

°
Variance
Requests
 
When
requests
for
variances,
net
effluent
limitations,
pretreatment,
etc.,
are
filed
within
the
specified
time
but
not
granted
until
after
permit
issuance.

°
Adjust
limits
to
reflect
net
pollutant
treatment
 
Upon
request
of
a
permittee
who
qualifies
for
effluent
limitations
on
a
net
basis
under
40
CFR
§
§
122.45(
g)
and
(
h).

°
Insert
CWA
§
307(
a)
toxic
or
40
CFR
Part
503
sludge
use/
disposal
requirements.

°
Notification
Levels
 
To
establish
notification
levels
for
toxic
pollutants
that
are
not
limited
in
the
permit
but
must
be
reported
if
concentrations
in
the
discharge
exceed
these
levels.

Minor
modifications
are
generally
non­
substantive
changes
(
e.
g.,
typographical
errors
that
require
more
stringent
permit
conditions).
The
conditions
for
minor
modifications,
described
in
40
CFR
§
122.63,
are
shown
in
Exhibit
11­
8.

NPDES
Permit
Writers'
Manual
­
207
Chapter
11
Administrative
Process
11.3.3
Termination
of
Permits
EXHIBIT
11­
8
Conditions
Requiring
Minor
Modification
°
Typographical
errors
must
be
corrected.
°
More
frequent
monitoring
or
reporting
is
necessary.
°
An
interim
compliance
date
in
the
schedule
of
compliance
needs
revision,
provided
the
new
date
is
not
more
than
120
days
after
the
date
specified
in
the
permit
and
does
not
interfere
with
attainment
of
the
final
compliance
date
requirement.
°
Ownership
has
changed
but
no
other
change
is
necessary.
°
The
construction
schedule
for
a
new
source
discharger
needs
revision.
°
A
point
source
outfall
that
does
not
result
in
the
discharge
of
pollutants
from
other
outfalls
must
be
deleted
from
the
permit.
°
An
approved
local
pretreatment
program
must
be
incorporated
into
the
permit.

Situations
may
arise
during
the
life
of
the
permit
that
are
cause
for
termination
(
i.
e.,
cancellation,
revocation)
of
the
permit.
Such
circumstances
include
the
following
(
see
40
CFR
§
122.62(
b)):

°
Noncompliance
by
the
permittee
with
any
condition
of
the
permit
°
Misrepresentation
or
omission
of
relevant
facts
by
the
permittee
°
A
determination
that
the
permitted
activity
endangers
human
health
or
the
environment,
either
in
an
emergency
or
other
situation
°
A
temporary
or
permanent
reduction
or
elimination
of
a
discharge
(
e.
g.,
plant
closure).

Once
the
permit
is
terminated,
it
can
be
placed
into
effect
again
only
by
the
reissuance
process,
which
requires
a
new
permit
application.
All
of
the
above
situations
may
also
be
addressed
through
the
permit
modification
process
on
a
case­
by­
case
determination.

208
­
NPDES
Permit
Writers'
Manual
Administrative
Process
Chapter
11
11.3.4
Transfer
of
Permits
Regulatory
agencies
will
occasionally
receive
notification
of
a
change
in
ownership
of
a
facility
covered
by
a
NPDES
permit.
Such
changes
require
that
a
permit
be
transferred
by
one
of
two
provisions:

°
Transfer
by
Modification
or
Revocation
 
The
transfer
may
be
made
during
the
process
of
modification,
either
major
or
minor.
It
may
also
be
addressed
by
revoking
and
subsequently
reissuing
the
permit.

°
Automatic
Transfer
 
A
permit
may
be
automatically
transferred
to
a
new
permittee
if
three
conditions
are
met:

 
The
current
permittee
notifies
the
Director
30
days
in
advance
of
the
transfer
date.

 
The
notice
includes
a
written
agreement
between
the
old
and
new
owner
on
the
terms
of
the
transfer.

 
The
Director
of
the
regulatory
agency
does
not
indicate
that
the
subject
permit
will
be
modified
or
revoked.

NPDES
Permit
Writers'
Manual
­
209
Chapter
10
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
To
address
unique
permitting
situations,
the
CWA
and
NPDES
regulations
allow
permit
writers
to
grant
variances
under
certain
prescribed
conditions.
These
variances
may
apply
to
either
technology­
based
or
water
quality­
based
regulatory
requirements.

The
variances
available
under
the
NPDES
Program
are
described
below.

The
NPDES
Program
has
also
established
certain
requirements
to
ensure
that
NPDES
permits
address
the
statutory
and
regulatory
requirements
of
other
environmental
programs.
The
permit
writer
should
be
aware
of
these
other
programs
in
developing
permit
conditions,
and
work
with
the
regulatory
agencies
that
oversee
these
programs.
Section
10.3
describes
these
considerations.

10.1
Variances
to
Technology­
Based
Permit
Requirements
In
addition
to
specifying
national
goals
for
water
pollution
control,
the
CWA
provides
a
mechanism
for
modification
of
the
technology­
based
requirements
of
the
CWA
for
exceptional
cases.
These
modifications
are
called
variances.
Very
specific
data
requirements
must
be
met
by
an
applicant
before
a
variance
may
be
granted.
As
NPDES
Permit
Writers'
Manual
­
171
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
the
term
implies,
a
variance
is
the
unusual
situation,
and
the
permit
writer
should
not
expect
to
routinely
receive
variance
requests.
Nevertheless,
the
permit
writer
should
be
aware
of
the
major
types
of
variances
and
the
basic
requirements
for
each,

because
the
permit
writer
will
most
likely
be
the
person
to
conduct
the
initial
reviews
of
such
requests
before
submitting
them
for
review
to
the
State
Director
(
if
applicable),

the
EPA
Regional
office,
and
EPA
Headquarters.
The
permit
writer
should
consult
40
CFR
§
124.62
for
the
procedures
for
decisions
on
the
various
types
of
variances.

With
one
exception
(
fundamentally
different
factors
variance),
a
variance
request
must
be
submitted
before
the
close
of
the
public
comment
period
of
the
permit.
The
following
paragraphs
discuss
variances
and
the
factors
that
should
be
considered
in
a
technical
review
of
the
variance
request.

10.1.1
Economic
Variances
Section
301(
c)
of
the
CWA
provides
for
a
variance
for
nonconventional
pollutants
from
BAT­
based
effluent
limitations
due
to
economic
factors.
Note
that
there
are
no
implementing
regulations
for
§
301(
c);
rather,
variance
requests
must
be
made
and
reviewed
based
on
the
statutory
language
in
CWA
§
301(
c).
The
variance
may
also
apply
to
non­
guideline
limits
in
accordance
with
40
CFR
§
122.21(
m)(
2)(
ii).

The
request
for
the
variance
from
effluent
limitations
developed
from
BAT
guidelines
is
normally
filed
by
the
discharger
during
the
public
notice
period
for
the
draft
permit.

Other
filing
time
periods
may
apply,
as
specified
in
40
CFR
§
122.21(
m)(
2).
The
application
must
show
that
the
modified
requirements:

°
Represent
the
maximum
use
of
technology
within
the
economic
capability
of
the
owner
or
operator;
and
°
Will
result
in
further
progress
toward
the
no
discharge
goal.

The
methodologies
for
determining
economic
capability
for
utilities
is
different
than
that
used
for
other
industries.
Utilities
should
perform
two
financial
calculations.

Generally,
EPA
will
only
grant
a
variance
if
both
tests
indicate
that
the
pollution
control
equipment
is
not
economically
achievable
and
the
applicant
can
demonstrate
"
reasonable
further
progress."
Other
industry
categories
must
calculate
three
financial
tests
to
determine
if
they
are
eligible
on
economic
grounds
for
a
301(
c)
variance.

172
­
NPDES
Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
Guidance
for
conducting
these
financial
tests
is
available
from
EPA's
Office
of
Wastewater
Management.
Generally,
EPA
will
only
grant
a
variance
if
all
three
tests
indicate
that
the
required
pollution
control
is
not
economically
achievable
and
the
applicant
makes
the
requisite
demonstration
about
"
reasonable
further
progress."

With
respect
to
the
second
requirement
for
a
301(
c)
modification
(
reasonable
further
progress
toward
the
no­
discharge
goal),
the
applicant
must,
at
a
minimum,

demonstrate
compliance
with
all
applicable
BPT
limitations
and
pertinent
water
quality
standards.
In
addition,
the
proposed
alternative
must
provide
for
a
reasonable
degree
of
improvement
in
the
applicant's
discharge.

10.1.2
Variances
Based
on
Localized
Environmental
Factors
Section
301(
g)
of
the
CWA
provides
for
a
variance
for
certain
nonconventional
pollutants
from
BAT
effluent
guidelines
due
to
localized
environmental
factors.
These
pollutants
include
ammonia,
chlorine,
color,
iron,
and
total
phenols.
The
discharger
must
file
a
variance
application
that
meets
the
following
requirements:

°
The
modified
requirements
must
result
in
compliance
with
BPT
and
water
quality
standards
of
the
receiving
stream.

°
No
additional
treatment
will
be
required
of
other
point
or
nonpoint
source
dischargers
as
a
result
of
the
variance
approval.

°
The
modified
requirements
will
not
interfere
with
attainment
or
maintenance
of
water
quality
to
protect
public
water
supplies,
or
with
protection
and
propagation
of
a
balanced
population
of
shellfish,
fish,
and
wildfowl,
and
will
allow
recreational
activities
in
and
on
the
water.
Also,
the
modified
requirements
will
not
result
in
quantities
of
pollutants
that
may
reasonably
be
anticipated
to
pose
an
unacceptable
risk
to
human
health
or
the
environment,
cause
acute
or
chronic
toxicity,
or
promote
synergistic
properties.

The
permit
writer
should
review
the
request
to
ensure
that
it
complies
with
each
of
the
requirements
for
this
type
of
variance.
This
variance
request
involves
a
great
deal
of
water
quality
assessment,
including
aquatic
toxicity,
mixing
zone
and
dilution
model
analysis,
and
possible
site­
specific
criterion
development.
In
addition,
many
complex
human
health
effects
must
be
assessed,
including
carcinogenicity,

teratogenicity,
mutagenicity,
bioaccumulation,
and
synergistic
propensities.
All
permit
NPDES
Permit
Writers'
Manual
­
173
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
writers
should
use
the
EPA
draft
301(
g)
technical
guidance
manual
to
assess
a
completed
variance
request.
Typical
industries
that
have
applied
for
301(
g)
variances
include
Iron
and
Steel
Manufacturing,
Steam
Electric
Power
Generating,
Inorganic
Chemicals
Manufacturing,
Nonferrous
Metals
Manufacturing,
Aluminum
Forming,
and
Pesticides
Manufacturing
facilities.

10.1.3
Marine
Discharge
Variances
Section
301(
h)
of
the
CWA
provides
for
variances
from
secondary
treatment
standards
for
POTWs
that
discharge
into
marine
waters
if
the
modified
requirements
do
not
interfere
with
the
attainment
or
maintenance
of
water
quality.
EPA
has
promulgated
specific
regulations
pertaining
to
CWA
§
301(
h)
that
are
provided
in
40
CFR
Part
125,
Subpart
G.

All
301(
h)
modified
permits
must
contain
the
following
specific
permit
conditions:

°
Effluent
limitations
and
mass
loadings
that
will
assure
compliance
with
40
CFR
Part
125,
Subpart
G
°
Compliance
schedules
for
pretreatment
program
development,
a
nonindustrial
toxics
control
program,
and
control
of
combined
sewer
overflows
°
Monitoring
program
requirements
that
include
biomonitoring,
water
quality,
and
effluent
monitoring
°
Reporting
requirements
that
include
the
results
of
the
monitoring
programs.

Also,
no
new
or
substantially
increased
discharges
from
the
point
source
of
the
affected
pollutant
can
be
released
above
that
volume
of
discharge
specified
in
the
permit.

EPA
has
developed
several
guidance
manuals
related
to
301(
h)
variances,

including
the
Revised
Section
301(
h)
Technical
Support
Document.
73
73USEPA
(
1982).
Revised
Section
301(
h)
Technical
Support
Document.
EPA­
430/
9­
82­
011.
Office
of
Water.

174
­
NPDES
Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
10.1.4
Fundamentally
Different
Factors
Variances
Section
301(
n)
of
the
CWA
provides
for
variances
based
upon
fundamentally
different
factors
(
FDF)
for
BAT
and
BCT
pollutants
while
40
CFR
Part
125,
Subpart
D
provides
the
regulatory
authority
for
BPT
variances.
FDF
variances
for
direct
dischargers
are
available
from
effluent
limitations
guidelines
for
toxic,
conventional,

and
nonconventional
pollutants
if
the
individual
facility
is
found
to
be
fundamentally
different
from
the
factors
considered
in
establishing
the
effluent
guidelines.
There
is
no
FDF
variance
allowed
from
NSPS.
The
FDF
variance
for
BPT
must
be
filed
by
the
close
of
the
public
comment
period
under
40
CFR
§
124.10.
The
FDF
variance
for
BAT
or
BCT
must
be
requested
by
the
discharger
within
180
days
of
the
guideline
promulgation.
Where
a
FDF
variance
request
is
approved,
calculated
alternative
limits
cannot
be
any
less
stringent
than
justified
by
the
fundamental
difference
and
cannot
cause
violations
of
water
quality
standards.

Factors
needed
to
justify
a
BPT
FDF
variance
must
be
related
to
a
discharger's
facilities,
equipment,
processes,
and
compliance
cost
that
are
different
from
those
considered
in
the
development
of
the
guidelines.
Factors
for
BAT
and
BCT
variance
requests
are
similar
except
that
cost
cannot
be
considered.
Additional
factors
that
cannot
be
considered
for
any
FDF
variance
request
include
the
feasibility
of
installing
the
necessary
treatment
within
the
given
time
frame,
a
claim
that
the
limits
cannot
be
achieved
with
the
given
technology
(
unless
supported
with
data),
the
discharger's
ability
to
pay,
or
the
impact
on
local
receiving
water
quality.
The
review
or
proposal
of
an
FDF
variance
is
completed
on
a
case­
by­
case
basis.
The
burden
of
proof
lies
with
the
entity
requesting
the
variance.

10.1.5
Thermal
Discharge
Variances
Section
316(
a)
of
the
CWA
provides
for
variances
from
effluent
limitations
for
the
thermal
component
of
a
discharge.
Regulations
for
submitting
and
reviewing
thermal
discharge
variance
requests
are
promulgated
at
40
CFR
Part
125,
Subpart
H.

Less
stringent
alternative
thermal
effluent
limits
may
be
included
in
permits
if
the
discharger
demonstrates
that
such
effluent
limits
are
more
stringent
than
necessary
to
assure
the
protection
and
propagation
of
a
balanced,
indigenous
community
of
shellfish,
fish
and
wildlife
in
and
on
the
body
of
water
into
which
the
discharge
is
NPDES
Permit
Writers'
Manual
­
175
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
made,
taking
into
account
the
cumulative
impact
of
its
thermal
discharge
together
with
all
other
significant
impacts
on
the
species
affected.

10.1.6
Net
Credits
In
some
cases,
solely
as
a
result
of
the
level
of
pollutants
in
the
intake
water,

facilities
are
faced
with
situations
in
which
technology­
based
limits
are
difficult
or
impossible
to
meet
with
BAT/
BCT
technology.
Under
certain
circumstances,
the
NPDES
regulations
allow
credit
for
pollutants
in
intake
water.
The
following
requirements
have
been
established
in
40
CFR
§
122.45(
g)
for
establishing
net
limitations:

°
Credit
for
generic
pollutants,
such
as
BOD
5
or
TSS,
are
only
authorized
where
the
constituents
resulting
in
the
effluent
BOD
5
and
the
TSS
are
similar
between
the
intake
water
and
the
discharge.

°
Credit
is
only
authorized
up
to
the
extent
necessary
to
meet
the
applicable
limitation
or
standard,
with
a
maximum
value
equal
to
the
influent
concentration.

°
Intake
water
must
be
taken
from
the
same
body
of
water
into
which
the
discharge
is
made.

°
Net
credits
do
not
apply
to
the
discharge
of
raw
water
clarifier
sludge
generated
during
the
treatment
of
intake
water.

Permit
writers
are
authorized
to
grant
net
credits
for
the
quantity
of
pollutants
in
the
intake
water
where
the
applicable
effluent
guidelines
specify
that
the
guidelines
are
to
be
applied
on
a
net
basis
or
where
the
pollution
control
technology
would,
if
properly
installed
and
operated,
meet
applicable
effluent
guidelines
limitations
and
standards
in
the
absence
of
the
pollutants
in
the
intake
waters.

10.2
Variances
to
Water
Quality­
Based
Permit
Requirements
Several
types
of
variances
exist
that
may
change
the
fundamental
basis
of
water
quality­
based
effluent
limitations,
specifically:

°
Site­
specific
water
quality
criteria
modification,
°
Designated
use
reclassification,
and
°
Water
quality
standard
variance.

Each
of
these
variances
are
described
below.

176
­
NPDES
Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
10.2.1
Site­
Specific
Water
Quality
Criteria
Modification
Section
304(
a)
of
the
CWA
recommends
procedures
for
States
to
develop
water
quality
criteria.
The
State
does
have
the
option
of
modifying
water
quality
criteria
on
a
site­
specific
basis.
Setting
site­
specific
criteria
may
be
appropriate
where
background
water
quality
parameters,
such
as
pH,
hardness,
temperature,
and
color
appear
to
differ
significantly
from
the
laboratory
water
used
to
develop
the
CWA
§
304(
a)
criteria;
or
the
types
of
local
aquatic
organisms
differ
significantly
from
those
actually
tested
in
developing
the
CWA
§
304(
a)
criteria.
Modifications
change
water
quality
criteria
permanently,
while
maintaining
the
existing
designated
uses.

10.2.2
Designated
Use
Reclassification
Once
a
use
has
been
designated
for
a
particular
water
body
or
segment,
the
water
body
or
water
body
segment
cannot
be
reclassified
for
a
different
use
except
under
specific
conditions.
To
remove
a
designated
use,
as
specified
in
Section
101(
a)(
2)
of
the
CWA,
the
State
must
perform
a
use
attainability
analysis
pursuant
to
40
CFR
§
131.10(
j).
The
Water
Quality
Standards
Handbook:
Second
Edition
74
discusses
use
attainability
analyses
in
greater
detail.
Reclassifying
a
water
body
causes
a
permanent
change
in
the
water
quality
standard
for
that
water
body.

10.2.3
Water
Quality
Standard
Variance
Water
quality
standard
variances
require
similar
substantive
and
procedural
requirements
as
removing
a
designated
use,
but
unlike
use
removal,
variances
are
both
discharger
and
pollutant
specific,
are
time­
limited,
and
do
not
forego
the
currently
designated
use
of
a
water
body.
A
variance
is
appropriate
where
the
State
believes
that
the
standard
can
be
ultimately
attained.
By
maintaining
the
standard
rather
than
changing
it,
the
State
will
assure
that
further
progress
is
made
in
improving
the
water
quality
and
attaining
the
standard.
State­
adopted
variances
have
been
approved
by
EPA
where,
among
other
things,
the
State
demonstrates,
consistent
with
40
CFR
Part
131,
that
meeting
the
standard
is
unattainable
based
on
one
or
more
of
the
grounds
outlined
in
40
CFR
§
131.10(
g).
The
variance
is
granted
for
a
specified
period
of
time
74USEPA
(
1994).
Water
Quality
Standards
Handbook:
Second
Edition.
EPA
823­
B­
94­
005a.
Office
of
Water.

NPDES
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Writers'
Manual
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Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
and
rejustified
at
least
every
3
years
as
reasonable
progress
is
made
toward
meeting
the
standards.

Modifications
of
or
variances
to
water
quality
standards
have
several
effects
on
permit
limits.
Specifically,
these
variances
change
the
fundamental
basis
of
water
quality­
based
effluent
limits,
potentially
impacting
the
reasonable
potential
determination
and
possibly
resulting
in
more
or
less
stringent
limitations.
It
is
the
permit
writer's
responsibility
to
ensure
that
the
variance
is
properly
reflected
in
the
NPDES
permit.

10.3
Additional
Programmatic
Considerations
and
Requirements
This
section
addresses
additional
programmatic
requirements
that
must
be
considered
during
permit
development.
These
requirements
include
anti­
backsliding
and
compliance
with
other
Federal
laws.

10.3.1
Anti­
Backsliding
In
general,
the
term
"
anti­
backsliding"
refers
to
a
statutory
provision
that
prohibits
the
renewal,
reissuance,
or
modification
of
an
existing
NPDES
permit
that
contains
effluents
limits,
permit
conditions,
or
standards
that
are
less
stringent
than
those
established
in
the
previous
permit.
There
are,
however,
exceptions
to
the
prohibition
 
determining
the
applicability
and
circumstances
of
the
exceptions
requires
a
familiarity
with
both
the
statutory
and
regulatory
language
that
addresses
the
issue
of
"
anti­
backsliding."

Section
402(
o)
of
the
Clean
Water
Act
establishes
express
statutory
language
prohibiting
the
backsliding
of
effluent
limitations.
Section
402(
o)
consists
of
three
main
parts.
First,
section
402(
o)(
1)
prohibits
(
subject
to
exceptions
in
sections
303(
d)(
4)

and/
or
402(
o)(
2))
the
relaxation
of
effluent
limitations
for
two
situations:

(
1)
When
a
permittee
seeks
to
revise
a
technology­
based
effluent
limitation
based
on
best
professional
judgment
to
reflect
a
subsequently
promulgated
effluent
guideline
which
is
less
stringent,
and
178
­
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Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
(
2)
When
a
permittee
seeks
relaxation
of
an
effluent
limitation
which
is
based
upon
a
State
treatment
standard
or
water
quality
standard.

Second,
Section
402(
o)(
2)
outlines
specific
exceptions
to
the
general
prohibition
against
establishment
of
less
stringent
effluent
limitations.
Codified
in
the
NPDES
regulations
at
40
CFR
122.44(
l),
Section
402(
o)(
2)
provided
that
the
establishment
of
less
stringent
limits
may
be
allowed
where:

(
1)
There
have
been
material
and
substantial
alternations
or
additions
to
the
permitted
facility
which
justify
this
relaxation.

(
2)
New
information
(
other
than
revised
regulations,
guidance,
or
test
methods)
is
available
that
was
not
available
at
the
time
of
permit
issuance
which
would
have
justified
a
less
stringent
effluent
limitation.

(
3)
Technical
mistakes
or
mistaken
interpretations
of
the
law
were
made
in
issuing
the
permit
under
Section
402(
a)(
1)(
b).

(
4)
Good
cause
exists
due
to
events
beyond
the
permittee's
control
(
e.
g.,
acts
of
God)
and
for
which
there
is
no
reasonably
available
remedy.

(
5)
The
permit
has
been
modified
under
40
CFR
§
122.62,
or
a
variance
has
been
granted.

(
6)
The
permittee
has
installed
and
properly
operated
and
maintained
required
treatment
facilities
but
still
has
been
unable
to
meet
the
permit
limitations
(
relaxation
may
only
be
allowed
to
the
treatment
levels
actually
achieved).

Although
the
statute
identified
six
exceptions
where
effluent
limitations
may
be
relaxed,
the
language
specifically
stated
that
exceptions
3
and
5
(
as
listed
above)
do
not
apply
to
water
quality­
based
effluent
limitations.
Thus,
exceptions
3
and
5
would
only
apply
to
technology­
based
effluent
limitations
derived
using
best
professional
judgment.

Third,
Section
402(
o)(
3)
prohibits
the
relaxation
of
effluent
limitations
in
all
cases
if
a
revised
effluent
limitation
would
result
in
a
violation
of
applicable
effluent
limitation
guidelines
or
water
quality
standards,
including
antidegradation
requirements.

Thus,
even
if
any
of
the
backsliding
exceptions
outlined
in
either
the
statute
or
NPDES
Permit
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Manual
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179
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
regulations
are
applicable
and
met,
Section
402(
o)(
3)
acts
as
a
floor
and
restricts
the
extent
to
which
effluent
limitations
may
be
relaxed.
This
requirement
affirms
existing
provisions
of
the
CWA
that
require
permit
limits,
standards,
and
conditions
to
ensure
compliance
with
applicable
technology­
based
limits
and
water
quality
standards.

EPA's
current
regulations
which
address
the
issue
of
anti­
backsliding
reflect
the
prohibition
imposed
by
Section
402(
o)
for
the
first
situation;
revision
of
existing
BPJbased
permit
limitations
to
reflect
subsequently
issued
effluent
guidelines
(
40
CFR
122.44(
l)(
2)).
However,
the
regulations
have
not
been
revised
to
reflect
the
prohibition
of
backsliding
for
the
second
situation:
relaxation
of
effluent
limitations
established
on
the
basis
of
Sections
301(
b)(
1)(
C)
or
303(
d)
or
(
3).
EPA
believes
the
water
quality
provisions
must
be
implemented
based
upon
interpretation
of
the
CWA
in
the
meantime.
As
such,
the
remainder
of
the
discussion
on
anti­
backsliding
provisions
will
focus
on
clarifying
the
intent
of
the
statute
as
it
relates
to
relaxation
of
water
qualitybased
effluent
limitations.
In
addition,
Exhibit
10­
1
provides
a
graphical
interpretation
of
the
backsliding
provisions
as
they
related
to
the
relaxation
of
WQBELs.

EPA
has
consistently
interpreted
Section
402(
o)(
1)
of
the
CWA
to
allow
relaxation
of
water
quality­
based
effluent
limitations
(
WQBELs)
if
either
the
requirements
of
Section
402(
o)(
2)
or
section
303(
d)(
4)
are
met.
These
two
provisions
constitute
independent
exceptions
to
the
prohibition
against
relaxation
of
permit
limits.

If
either
is
met,
relaxation
is
permissible.

Section
303(
d)(
4)
has
two
parts:
paragraph
(
A)
which
applies
to
"

nonattainment
waters"
and
paragraph
(
B)
which
applies
to
"
attainment
waters."

°
Non­
attainment
water
 
Section
303(
d)(
4)(
A)
allows
establishment
of
less
stringent
WQBEL
when
the
receiving
water
has
been
identified
as
not
meeting
applicable
water
quality
standards
(
i.
e.,
a
"
nonattainment
water"),
if
the
permittee
meets
two
conditions.
First,
the
existing
WQBEL
must
have
been
based
on
a
total
maximum
daily
load
(
TMDL)
or
other
wasteload
allocation
(
WLA)
established
under
Section
303.
Second,
relaxation
of
a
WQBEL
is
only
allowed
if
attainment
of
water
quality
standards
must
be
ensured.

°
Attainment
water
 
Section
303(
d)(
4)(
B)
applies
to
waters
where
the
water
quality
equals
or
exceeds
levels
necessary
to
protect
the
designated
use,
or
to
otherwise
meet
applicable
water
quality
standards
(
i.
e.,
an
"
attainment
180
­
NPDES
Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
EXHIBIT
10­
1Anti­
Backsliding
Rules
Relating
to
Water
Quality­
Based
Effluent
Limitations
EXHIBIT
10­
1
Anti­
Backsliding
Rules
Relating
to
Water
Quality­
Based
Effluent
Limitations
Yes
Yes
No
No
Yes
Yes
Yes
No
402(
o)(
1)/
303(
d)(
4)

Are
water
quality
standards
attained?
402(
o)(
2)

Is
a
listed
exception
met?

Is
effluent
limit
based
on
a
State
water
quality
standard?

303(
d)(
4)(
B)

Attainment
waters
Is
revision
consistent
with
antidegadation?
303(
d)(
4)(
A)

Non­
Attainment
waters
Is
limit
based
on
aTMDL/
WLA?

Is
attainment
of
water
quality
standards
assured?

(
including
antidegradation?)

Revision
not
Allowed
Revision
allowed
Revision
not
allowed
No
Yes
No
See
existing
regulations
40
C.
F.
R.
122.44(
I)

402(
o)(
3)

Does
revision
comply
with
effluent
guidelines
and
water
quality
standard?
No
100D­
03
or
NPDES
Permit
Writers'
Manual
­
181
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
water").
Under
Section
303(
d)(
4)(
B),
WQBELs
may
only
be
relaxed
where
the
action
is
consistent
with
State's
anti­
degradation
policy.

As
previously
mentioned,
Section
402(
o)(
2)
outlines
specific
exceptions
to
the
general
prohibition
against
backsliding
from
WQBELs.
These
exceptions
are
independent
of
the
Section
303(
d)(
4)
exception
discussed
above
and
are
also
applicable
to
the
backsliding
of
BPJ
limits
to
reflect
subsequently
promulgated
less
stringent
guidelines.

Finally,
all
other
types
of
backsliding
[
for
example,
backsliding
from
effluent
guideline­
derived
limits,
from
new
source
performance
standards,
from
existing
BPJ
limits
to
new
BPJ
limits,
or
from
water
quality­
related
standards
or
conditions
(
except
for
effluent
limitations)]
remain
unaffected
by
the
1987
WQA
amendments
and
EPA's
existing
regulations
at
40
CFR
122.44(
l)(
1)
will
continue
to
govern
them.
This
is
because
Section
402(
o)
only
prohibits
the
backsliding
of
"
effluent
limits,"
not
other
standards
or
conditions
such
as
monitoring
frequency
or
changes
in
species
or
protocol
for
whole
effluent
toxicity
(
WET)
testing.
The
relaxation
of
all
other
types
of
standards
or
conditions
contained
in
a
permit
are,
however,
subject
to
EPA's
existing
backsliding
regulations
at
40
CFR
122.41(
l)(
1).
Under
these
regulations,
a
permittee
must
meet
a
cause
for
modification
in
order
to
allow
relaxation.

182
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Writers'
Manual
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to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
Example
1
Scenario:

°
A
POTW
seeks
to
relax
its
WQBEL
for
pollutant
X.

°
Current
permit
limitation
is
based
on
the
TMDL
and
WLA
for
the
POTW
developed
in
accordance
with
40
CFR
130.7.

°
The
POTW
is
in
compliance
with
its
existing
limitation
and
the
applicable
water
quality
standards
for
pollutant
X
is
attained.

°
The
POTW
has
developed
new
models
with
new
river
flow
information,
which
indicate
that
the
water
quality
standards
for
pollutant
X
would
be
maintained
with
a
relaxed
permit
limitation.

°
May
the
effluent
limitation
for
pollutant
X
be
relaxed?

Answer:

Possibly.
Under
the
interpretation
discussed
above,
WQBELs
may
be
relaxed
where
one
of
the
exceptions
in
§
402(
o)(
1)
or
40
CFR
122.44(
l)(
2)
are
met.
In
this
case,
although
new
information
is
being
relied
on
to
request
the
modification,
§
402(
o)(
2)
will
not
justify
the
request
unless
the
State
reduces
the
pollutant
loadings
from
other
point
sources
or
non­
point
sources
of
pollution.
This
is
because,
as
discussed
above,
paragraph
§
402(
o)(
2)
restricts
the
use
of
new
information
to
cases
where
there
is
a
decrease
in
the
amount
of
pollutants
being
discharged.

The
§
402(
o)(
1)
exceptions,
on
the
other
hand,
may
justify
the
request.
In
this
case,
the
paragraph
(
o)(
1)
exception
that
is
relevant
is
the
reference
to
§
303(
d)(
4)(
B).
It
provides
that
for
receiving
waters
that
where
water
quality
standards
are
attained,
permit
limitations
based
on
a
TMDL/
WLA
or
other
permit
standard
may
be
relaxed
only
if
a
State's
antidegradation
policy
are
met.

Example
2
Scenario:

°
The
State
has
established
a
technology­
based
treatment
standard
for
fecal
coliform
pursuant
to
§
301(
b)(
1)(
C).

°
The
State
later
relaxes
this
standard.

°
A
POTW,
which
has
been
in
violation
of
this
limit,
requests
a
revision
of
its
permit
limit
for
fecal
coliform
to
reflect
the
new
standard.

°
Water
quality
standards
for
fecal
coliform
are
not
being
attained.

°
Models
show
that
attainment
of
water
quality
standards
will
be
assured
if
the
POTW
complies
with
a
revised,
relaxed
permit
limitation
for
fecal
coliform.

°
There
was
no
TMDL
or
WLA
performed
because
the
standard
was
a
State
technology­
based
standard.

°
May
the
permit
limitation
be
relaxed?

Answer:

No.
Under
§
402(
o)(
1),
the
applicable
provision
is
§
303(
d)(
4)(
A).
This
subsection
does
not
authorize
backsliding
in
this
case
because
it
only
applies
to
permit
limitations
based
on
a
TMDL/
WLA.
Here,
the
limitation
in
question
is
based
on
a
type
of
State
treatment
standard.

Furthermore,
if
the
permit
sought
to
apply
the
§
402(
o)(
2)
exceptions,
the
new
information
provision
would
not
allow
the
revision.
New
information
does
not
include
"
revised
regulations."

NPDES
Permit
Writers'
Manual
­
183
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
Example
3
Scenario:

°
The
State
has
a
narrative
water
quality
criterion
of
"
no
toxics
in
toxic
amounts."

°
On
the
basis
of
WET
testing
data
or
other
information,
the
State
finds
reasonable
potential
to
exceed
the
narrative
water
quality
criterion
and
imposes
a
WET
limitation
under
40
CFR
122.44(
d)(
1)(
v).

°
The
permittee
determines
that
pollutant
Z
is
the
cause
of
the
WET
in
its
discharge.

°
The
permittee
can
demonstrate
through
sufficient
data
(
including
WET
testing
data)
that
an
effluent
limitation
for
pollutant
Z
will
assure
compliance
with
the
narrative
water
quality
standards
as
well
as
the
State's
numeric
criteria
for
pollutant
Z
as
required
by
40
CFR
122.44(
d)(
1)(
v).

°
May
the
State
modify
the
permit
to
delete
the
WET
limitation
and
to
add
the
limitation
for
pollutant
Z?

Answer:

§
303(
d)(
4)
may
justify
this
action.
The
applicable
provision
of
§
303(
d)(
4)
is
§
303(
d)(
4)(
B)
because
the
narrative
water
quality
standards
is
currently
attained.
(
The
permittee
is
currently
complying
with
the
existing
WET
limitation
to
attain
and
maintain
the
State's
narrative
water
quality
standards.)
Under
§
303(
d)(
4)(
B),
the
permittee
may
backslide
so
long
as
antidegradation
requirements
will
be
met,
and
the
relaxed
limitation
will
not
cause
a
violation
of
any
effluent
limitations
guidelines
and
water
quality
standards
applicable
to
the
discharge.
In
this
case,
this
appears
likely
because
the
discharger
can
demonstrate
that
the
new
limitation
for
pollutant
Z
will
assure
compliance
with
applicable
narrative
as
well
as
numeric
water
quality
standards.

Example
4
Scenario:

°
An
industrial
permittee
seeks
to
revise
its
WQBEL
of
1000
mg/
L
for
TSS
to
6000
mg/
L,
its
actual
discharge
level.

°
The
current
permit
limitation
is
based
upon
a
TMDL
and
WLA
for
the
permittee,
which
were
developed
in
accordance
with
40
CFR
130.7.

°
The
water
quality
standards
for
TSS
are
not
being
attained.

°
A
permit
limit
of
6000
mg/
L
is
consistent
with
applicable
effluent
guidelines.

°
New
modeling
information
shows
that
the
water
quality
standards
for
TSS
will
be
attained
with
a
permit
limitation
of
4000
mg/
L.

°
May
the
permit
limitation
be
revised
from
1000
mg/
L
to
6000
mg/
L?

Answer:

No.
However,
the
permit
limitation
could
be
relaxed
to
4000
mg/
L
under
either
§
402(
o)(
1)
or
the
§
402(
o)(
2)
exceptions.

The
water
quality
standards
for
TSS
is
not
currently
being
attained.
Therefore,
under
§
402(
o)(
1),
the
applicable
exception
is
§
303(
d)(
4)(
A).
In
this
case,
the
permitting
authority
may
allow
backsliding
to
4000
mg/
L
because
the
existing
effluent
limitation
is
based
upon
a
TMDL/
WLA
and
the
data
shows
that
attainment
of
the
water
quality
standards
is
assured
with
a
permit
limitation
of
4000
mg/
L
(
but
not
with
a
limitation
of
6000
mg/
L).

Alternatively,
under
§
402(
o)(
2),
new
information
can
be
relied
on
to
relax
permit
limitations
where
there
is
a
reduction
in
pollutant
loadings
and,
pursuant
to
§
402(
o)(
3),
where
water
quality
standards
are
complied
with.
Again,
water
quality
standards
are
being
met
in
this
case,
and
there
also
will
be
a
reduction
in
actual
pollutant
loadings
since
the
new
proposed
permit
level
of
4000
mg/
L
will
represent
a
real
reduction
compared
with
the
actual
discharge
levels
of
6000
mg/
L.

184
­
NPDES
Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
10.3.2
Considerations
for
Other
Federal
Laws
This
section
addresses
several
Federal
laws
that
impact
NPDES
permitting.
It
is
noteworthy
that
the
requirements
imposed
under
several
of
these
statutes
(
e.
g.,
the
NHPA,
ESA,
FWCA,
and
NEPA,
discussed
below),
only
apply
to
Federal
or
federally
supported
actions
(
e.
g.,
EPA
issuance
of
permits).
Under
these
particular
statutes,

purely
State
actions
are
not
regulated.
However,
many
States
may
have
enacted
State
legislation
that
is
modeled
on
Federal
law
and,
therefore,
it
is
prudent
to
review
State
law
in
these
areas
prior
to
preparing
a
NPDES
permit.

National
Historic
Preservation
Act
Amendments
of
1992
The
National
Historic
Preservation
Act
(
NHPA)
establishes
Federal
programs
to
preserve
the
historical
and
cultural
foundations
of
the
nation.
Regulations
under
Section
106
of
this
Act
require
any
Federal
agency,
in
consultation
with
the
Advisory
Council
on
Historic
Preservation,
to
take
into
account
the
effect
of
proposed
Federal
or
Federally
assisted
undertakings
on
architectural,
archeological,
historic,
or
cultural
resources
listed,
or
eligible
for
listing,
on
the
National
Register
of
Historic
Places.
This
has
been
interpreted
(
see
EPA
Memorandum
dated
March
15,
1994,
from
Steven
A.

Herman,
Assistant
Administrator
to
Carol
Browner,
Administrator,
entitled
"
EPA
Policy
Decision
of
a
Strategy
For,
and
Interim
Compliance
with
the
National
Historic
Preservation
Act
Amendments")
to
mean
that
consultations
must
be
made
for
direct
EPA
actions
and
for
individual
State
actions
that
EPA
funds
under
its
programs.

However,
for
State
actions
not
directly
funded
by
EPA
under
EPA­
authorized
programs,
consultation
would
occur
on
a
voluntary
basis.

To
date,
guidance
for
the
permit
writer
in
considering
the
NHPA
requirements
is
not
available.
In
general,
the
permit
writer
must
ensure
that
the
proposed
discharge
to
be
authorized
under
the
NPDES
permit
will
not
have
an
adverse
effect
on
a
site
listed,

or
eligible
for
listing,
on
the
National
Register
of
Historic
Places.
The
permit
writer
may
want
to
require
that
the
permittee
show
that
sufficient
research
has
been
conducted
to
identify
whether
a
site
on
the
Register
is
located
within
the
area.

Sufficient
research
should
include
review
of
the
National
Register
and
information
gathering
from
local
governments,
Indian
tribes,
public
and
private
organizations,
and
the
State
Historic
Preservation
Officer
(
36
CFR
Part
880).
An
evaluation
of
potential
effects
should
be
documented.
Written
documentation
of
the
evaluation
should
be
NPDES
Permit
Writers'
Manual
­
185
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
submitted
to
the
State
Historic
Preservation
Office
and
included
in
the
permit
file
and
fact
sheet.

Endangered
Species
Act
of
1973
The
goal
of
the
Endangered
Species
Act
(
ESA)
of
1973
is
to
provide
protection
and
support
in
the
conservation
and
recovery
of
threatened
and
endangered
species
and
the
ecosystem
on
which
they
depend.
Section
7
of
the
ESA
requires
Federal
agencies
to
ensure
that
any
action
authorized,
funded,
or
carried
out
by
a
Federal
agency
not
jeopardize
the
continued
existence
of
a
listed
or
candidate
species
or
result
in
the
destruction
or
adverse
modification
of
its
habitat.
Since
the
issuance
of
NPDES
permits
by
EPA
is
a
Federal
action,
consideration
of
a
permitted
discharge
and
its
effect
on
any
threatened
and/
or
endangered
species
is
appropriate.
Section
9
of
the
ESA
prohibits
the
"
taking"
of
any
listed
endangered
and/
or
threatened
species.

The
ESA
regulations
require
that
consultation
with
the
National
Marine
Fisheries
Service
(
NMFS)
and/
or
the
Fish
and
Wildlife
Service
(
FWS),
as
appropriate,
occur
when
the
Federal
activity
is
one
which
may
effect
an
endangered
and/
or
threatened
species
or
habitat.
Effect
is
defined
as
both
detrimental
and
beneficial.
Consultations
may
be
either
informal
or
formal.
An
informal
consultation
determines
if
an
action
is,

or
is
not,
likely
to
adversely
effect
the
species.
A
formal
consultation
is
required
if
the
findings
show
that
there
is
a
likelihood
for
adverse
impacts
and
evaluates
if
the
proposed
action
is
likely
to
jeopardize
the
continued
existence
of
the
species.
It
is
EPA's
responsibility
to
ensure
that
consultation
occurs,
however,
a
non­
Federal
representative
may
be
designated
for
the
informal
consultation
(
i.
e.,
the
permittee).

To
date,
EPA
has
not
yet
entered
into
a
national
agreement
with
NMFS
or
FWS
on
the
scope
of
consultation
requirements
for
NPDES
permits.
Until
then,
EPA
permit
writers
should
review
the
ESA
consultation
regulations
(
50
CFR
§
402)
and
coordinate
with
the
Region's
ESA
coordinator
(
if
such
a
position
has
been
established
in
a
particular
Region)
and
the
FWS/
NMFS
office(
s)
located
nearest
the
site.
In
evaluating
the
effects
of
a
discharge
upon
endangered
or
threatened
species,
the
study
should
identify
the
listed
and
candidate
species
and
their
habitats
which
occur
in
the
area
of
the
discharge.
This
information
can
be
obtained
from
discussions
with
local
FWS/

NMFS
biologists.
The
proposed
permit
limits
can
then
be
compared
to
any
existing
186
­
NPDES
Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
toxicological
data
and/
or
impacts
data
available
for
the
species.
Cumulative,

combined,
and
independent
effects
should
be
evaluated.
Additional
species­
specific
information
can
be
obtained
through
discussions
with
the
local
wildlife
and
aquatic
biologists
who
are
experts
on
a
particular
species
(
e.
g.,
EPA,
FWS/
NMFS,
State
Conservation,
universities).

It
is
EPA's
position
that
permits
issued
under
State
law
are
not
subject
to
ESA
consultation
because
they
are
not
Federal
Actions.
However,
State
NPDES
Programs
should
have
some
process
in
place
to
consider
potential
effects
on
endangered
and
threatened
species
and
their
habitat
if
they
are
known
to
occur
in
the
area
of
the
discharge
to
ensure
those
discharges
do
not
result
in
takes
of
listed
species.

Biological
Evaluations
(
informal)
or
Biological
Assessments
(
formal)
should
be
submitted
to
the
FWS/
NMFS
for
review
and
approval.
This
documentation
and
any
decisions
from
the
FWS/
NMFS
would
become
part
of
the
permit
documentation.

Wild
and
Scenic
Rivers
Act
The
1968
Wild
and
Scenic
Rivers
Act
protected
selected
rivers
from
construction
of
dams
and
excessive
commercial
development.
It
declared
that
"
the
established
national
policy
of
dam
and
other
construction
at
appropriate
section
of
the
rivers
of
the
United
States
needs
to
be
complemented
by
a
policy
that
would
preserve
other
selected
rivers
or
section
thereof
in
their
free­
flowing
condition"
[
Section
(
1)(
b)].

The
Act
defines
three
classes
of
protected
river
(
wild
river;
scenic
river;
recreational
river)
and
spells
out
in
considerable
detail
the
management
restrictions
to
be
established
for
these
rivers.
A
corridor
of
land
on
each
side
of
a
protected
river
is
also
protected.
The
corridor
is
to
average
no
more
than
320
acres
per
linear
mile
of
river
through
the
protected
stretch.
The
rights
of
landowners
within
this
corridor
are
maintained,
subject
to
restrictions
on
the
type
of
development
allowed.
Rivers
are
"
studied"
and
may
be
protected
for
up
to
three
years
during
the
study
period
during
which
a
river
has
the
status
of
a
protected
river.

NPDES
Permit
Writers'
Manual
­
187
Variances
to
Permit
Requirements
and
Chapter
10
Other
Regulatory
Considerations
Coastal
Zone
Management
Act
The
1972
Coastal
Zone
Management
Act
(
CZMA)
and
amendments
require
and
encourage
the
coastal
states
of
the
United
States
to
adopt
and
enforce
land­
use
plans
for
the
lands
and
water
adjacent
to
their
coasts.
"
Coastal
states,"
according
to
the
Act,
include
those
adjacent
to
the
Atlantic,
Pacific
or
Arctic
oceans,
the
Gulf
of
Mexico,

or
one
or
more
of
the
Great
Lakes.
These
States
are
required
to
adopt
coastal
management
plans
which
designate
boundaries,
identify
areas
of
particular
concern,

and
establish
an
inventory
of
permitted
uses
and
an
enforcement
mechanism.
Beach
access,
emergency
planning
and
erosion
control
also
must
be
addressed
in
the
plans.

EPA
and
other
Federal
agencies
must
coordinate
their
activities
on
coastal
lands
with
State
CZMA
plans.

Fish
and
Wildlife
Coordination
Act
The
Fish
and
Wildlife
Coordination
Act
(
FWCA)
of
1934
requires
mitigation
for
the
loss
of
wildlife
habitat
due
to
the
construction
of
Federal
water
resources
projects.

It
requires
designers
of
Federal
dams,
reservoirs,
and
irrigation
works
to
include
the
costs
and
benefits
to
fish
and
wildlife
when
determining
the
benefit/
cost
ratio
of
a
project.
It
requires
EPA
and
other
Federal
agencies
to
consult
with
State
and
Federal
wildlife
and
fisheries
agencies
in
order
to
minimize
the
impacts
of
the
activity
on
fish
and
wildlife.
The
Act
specifically
calls
for
ongoing
studies
by
the
United
States
Department
of
the
Interior
on
the
effects
of
waterborne
sewage
and
industrial
wastes
on
fish
and
wildlife.

National
Environmental
Policy
Act
The
1967
National
Environmental
Policy
Act
established
a
Federal
framework
for
policy
decisions
regarding
Federal
actions
that
will
have
a
significant
effect
on
the
environment.
"
Federal"
actions
generally
include
projects
undertaken
by
the
Federal
government,
as
well
as
non­
Federal
actions
eligible
for
Federal
assistance
and
non­

Federal
actions
that
require
Federal
permits
or
approvals.
Thus,
NEPA
requirements
apply
to
NPDES
permits
issued
by
EPA
to
new
sources
in
non­
delegated
States.
The
Act's
most
important
provision
is
Section
102(
2)(
c),
requiring
Federal
agencies
such
as
EPA
to
file
an
Environmental
Impact
Statement
(
EIS)
on
all
"
proposals
for
legislation
and
other
major
Federal
actions
significantly
affecting
the
quality
of
the
188
­
NPDES
Permit
Writers'
Manual
Variances
to
Permit
Requirements
and
Other
Regulatory
Considerations
Chapter
10
human
environment."
The
definition
of
what
constitutes
such
actions
is
an
ongoing
discussion.
The
Act
establishes
a
framework
for
cooperation
between
the
United
States
government
at
all
levels,
and
other
countries
on
environmental
matters.
It
also
established
the
Council
on
Environmental
Quality.

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Permit
Writers'
Manual
­
189
Chapter
9
Standard
Conditions
of
NPDES
Permits
This
chapter
describes
standard
conditions,
sometimes
called
"
boilerplate"

conditions,
that
consist
of
pre­
established
conditions
that
must
be
incorporated
into
every
permit.
The
standard
conditions
set
out
in
40
CFR
§
§
122.41
and
122.42
play
an
important
supporting
role
to
the
numeric
permit
limits
because
these
conditions
delineate
the
legal,
administrative,
and
procedural
requirements
of
the
permit.

Standard
conditions
may
be
inserted
verbatim
from
the
regulations
or
incorporated
into
the
permit
by
specific
reference
to
the
regulations.
Standard
conditions
cover
various
topics,
including
definitions,
testing
procedures,
records
retention,
notification
requirements,
penalties
for
noncompliance,
and
permittee
responsibilities.

The
use
of
standard
conditions
helps
ensure
uniformity
and
consistency
of
all
NPDES
permits
issued
by
authorized
States
or
EPA
Regional
offices.
The
permit
writer
needs
to
be
aware
of
the
contents
of
the
standard
conditions
because
it
may
often
be
necessary
to
explain
portions
of
these
conditions
to
a
permittee.
The
permit
writer
should
also
keep
abreast
of
any
changes
in
EPA's
standard
conditions
set
out
in
40
CFR
§
122.41
as
statutes
or
regulations
are
revised
periodically.

NPDES
Permit
Writers'
Manual
­
167
Chapter
9
Standard
Conditions
of
NPDES
Permits
9.1
Types
of
Standard
Conditions
A
brief
discussion
of
each
of
EPA's
standard
conditions
for
NPDES
permits
follows:

°
Duty
to
Comply
[
40
CFR
§
122.41(
a)]
 
The
permittee
must
comply
with
all
conditions
of
the
permit.
Noncompliance
is
a
violation
of
the
CWA
and
is
grounds
for
injunctive
relief,
substantial
monetary
penalties,
incarceration,
changes
or
terminations
to
the
permit,
or
denial
of
permit
renewal.

°
Duty
to
Reapply
[
40
CFR
§
122.41(
b)]
 
If
a
permittee,
after
the
expiration
of
its
permit,
desires
to
continue
its
activities,
it
must
reapply
for
and
obtain
a
new
permit.

°
Need
to
Halt
or
Reduce
Activity
not
a
Defense
[
40
CFR
§
122.41(
c)]
 
The
permittee
may
not
use
as
a
defense
the
reasoning
that
compliance
could
only
be
achieved
by
halting
or
reducing
the
permitted
activity.

°
Duty
to
Mitigate
[
40
CFR
§
122.41(
d)]
 
The
permittee
is
required
to
take
all
reasonable
steps
to
prevent
any
discharge
or
sludge
use
or
disposal
in
violation
of
this
permit
that
has
a
reasonable
likelihood
of
adversely
affecting
human
health
or
the
environment.

°
Proper
Operation
and
Maintenance
[
40
CFR
§
122.41(
e)]
 
The
permittee
must
properly
operate
and
maintain
all
equipment
and
treatment
systems
used
by
the
permittee
for
compliance
with
the
terms
of
the
permit.
The
permittee
must
provide
appropriate
laboratory
controls
and
quality
assurance
procedures.
Backup
systems
are
required
when
needed
to
ensure
compliance.
However,
each
main
line
unit
treatment
process
must
be
operated
as
a
minimum.

°
Permit
Actions
[
40
CFR
§
122.41(
f)]
 
The
permit
may
be
modified,
revoked,
reissued,
or
terminated
for
cause.
The
filing
of
a
request
by
the
permittee
for
a
modification,
revocation,
reissuance,
termination,
or
notification
of
planned
changes
or
anticipated
noncompliance
does
not
halt
any
permit
condition.

°
Property
Rights
[
40
CFR
§
122.41(
g)]
 
The
permit
does
not
convey
any
property
rights
of
any
sort,
or
any
exclusive
privilege.

°
Duty
to
Provide
Information
[
40
CFR
§
122.41(
h)]
 
The
permittee
must
transmit
any
information
needed
to
determine
compliance
with
the
permit
or
to
modify
the
permit.

°
Inspection
and
Entry
[
40
CFR
§
122.41(
i)]
 
The
permittee
must,
upon
presentation
of
valid
credentials
by
the
Director
or
his
representative,
allow
entry
into
the
premises
where
the
regulated
activity
and/
or
records
are
present.
The
Director
must
have
access
to
and
be
able
to
make
copies
of
any
required
records,
inspect
facilities,
practices,
operations,
and
equipment,
and
sample
or
monitor
at
reasonable
times.

168
­
NPDES
Permit
Writers'
Manual
Standard
Conditions
of
NPDES
Permits
Chapter
9
°
Monitoring
and
Records
[
40
CFR
§
122.41(
j)]
 
Samples
must
be
representative
of
the
monitored
activity.
Records
must
be
retained
for
3
years
(
5
years
for
sludge
activities)
subject
to
extension
by
the
Director.
Monitoring
records
must
identify
the
sampling
dates
and
personnel,
the
sample
location
and
time,
and
the
analytical
techniques
used
and
corresponding
results.
Wastewater
and
sludge
measurements
must
be
conducted
in
accordance
with
40
CFR
Parts
136
or
503
or
other
specified
procedures.
Falsification
of
results
is
a
violation.

°
Signatory
and
Certification
Requirements
[
40
CFR
§
122.41(
k)]
 
Applications,
reports,
or
information
submitted
to
the
Director
must
be
signed
and
certified.
Knowingly
making
false
statements,
representations,
or
certifications
is
subject
to
penalties.

°
Planned
Changes
[
40
CFR
§
122.41(
l)(
1)]
 
Notice
must
be
given
to
the
Director
as
soon
as
possible
of
any
planned
physical
alterations
and/
or
additions
to
the
facility.
This
notice
is
required
if
the
facility
changes
to
meet
the
criteria
for
a
new
source
or
the
nature
and
concentration
of
pollutants
are
affected.

°
Anticipated
Noncompliance
[
40
CFR
§
122.41(
l)(
2)]
 
The
permittee
must
give
advance
notice
of
any
conditions
that
may
result
in
noncompliance.

°
Permit
Transfers
[
40
CFR
§
122.41(
l)(
3)]
 
The
permit
is
not
transferable
except
after
written
notice
to
the
Director.
The
Director
may
require
modification
or
revocation
and
reissuance,
as
necessary.

°
Monitoring
Reports
[
40
CFR
§
122.41(
l)(
4)]
 
Reports
must
be
submitted
on
a
DMR
or
on
a
Director­
specified
form
for
sludge
use/
disposal
practices.
In
addition,
more
frequent
monitoring
must
be
reported.
Calculations
requiring
averaging
must
use
an
arithmetic
mean,
except
for
fecal
coliform.
Monitoring
results
must
be
reported
at
the
frequency
specified
in
the
permit.

°
Compliance
Schedules
[
40
CFR
§
122.41(
l)(
5)]
 
Reports
required
by
a
compliance
schedule
in
the
permit
must
be
submitted
within
14
days
of
the
due
date.

°
Twenty­
Four
Hour
Reporting
[
40
CFR
§
122.41(
l)(
6)]
 
The
permittee
must
report
any
noncompliance
that
may
endanger
human
health
or
the
environment
within
24
hours
after
becoming
aware
of
the
circumstance.
Within
5
days,
the
permittee
must
provide
a
written
submission
containing
the
information
outlined
in
40
CFR
§
122.41(
l)(
6)(
ii)
unless
the
requirement
is
waived
by
the
permitting
authority.

°
Other
Noncompliance
[
40
CFR
§
122.41(
l)(
7)]
 
The
permittee
must
report
all
instances
of
noncompliance
not
reported
under
other
specific
reporting
requirements
at
the
time
monitoring
reports
are
submitted.

°
Other
Information
[
40
CFR
§
122.41(
l)(
8)]
 
Where
the
permittee
becomes
aware
that
it
failed
to
submit
any
relevant
facts
in
its
application,
or
submitted
incorrect
information
in
its
application
or
other
reports,
it
must
promptly
submit
such
information.

NPDES
Permit
Writers'
Manual
­
169
Chapter
9
Standard
Conditions
of
NPDES
Permits
°
Bypass
[
40
CFR
§
122.41(
m)]
 
Intentional
diversions
of
untreated
waste
streams
from
any
portion
of
a
treatment
facility
are
prohibited
unless
(
1)
the
bypass
does
not
cause
effluent
to
exceed
limits,
and
(
2)
the
bypass
was
unavoidable
to
prevent
loss
of
life,
personal
injury,
or
severe
property
damage,
and
there
was
no
feasible
alternatives,
and
the
proper
notification
was
submitted.

°
Upset
[
40
CFR
§
122.41(
n)]
 
An
upset
can
be
used
as
an
affirmative
defense
in
actions
brought
to
the
permittee
for
noncompliance.
The
permittee
(
who
has
the
burden
of
proof)
must
have
operational
logs
or
other
evidence
that
shows
(
1)
when
the
upset
occurred
and
its
causes,
(
2)
that
the
facility
was
being
operated
properly,
(
3)
proper
notification
was
made,
and
(
4)
remedial
measures
were
taken.

9.2
Other
Standard
Conditions
In
addition
to
standard
conditions
specified
in
40
CFR
§
122.41,
40
CFR
§
122.42
sets
forth
additional
conditions
applicable
to
specified
categories
of
NPDES
permits.
These
conditions
include:

°
Existing
manufacturing,
commercial,
mining,
and
silvicultural
dischargers
must
notify
EPA
as
soon
as
they
know
or
have
reason
to
believe
that
the
discharge
has
or
will
exceed
notification
levels
set
forth
in
40
CFR
§
122.42(
a).

°
POTWs
must
provide
adequate
notice
to
EPA
for
new
introduction
of
pollutants
into
the
POTW,
for
substantial
changes
in
the
volume
or
character
of
pollutants,
and
related
information
specified
in
40
CFR
§
122.42(
b).

°
Large,
medium
or
EPA­
designated
municipal
separate
storm
sewer
systems
must
submit
an
annual
report
addressing
the
status,
and
changes
to,
the
storm
water
management
program,
water
quality
data
and
other
information
specified
in
40
CFR
§
122.42(
c).

170
­
NPDES
Permit
Writers'
Manual
Chapter
8
Special
Conditions
Special
conditions
in
NPDES
permits
are
designed
to
provide
an
additional
measure
of
control
(
beyond
numeric
effluent
limits)
for
the
reduction
of
discharges
of
pollutants
to
waters
of
the
United
States.
They
are
not
included
in
the
effluent
limitations
section
of
a
permit
because
they
do
not
contain
specific
numeric
limits.

The
purpose
of
special
conditions
is
to
encourage
the
permittee
to
undertake
activities
designed
to
reduce
the
overall
quantity
of
pollutants
being
discharged,
or
to
reduce
the
potential
for
discharges
of
pollutants.

There
are
many
different
reasons
to
incorporate
special
conditions
into
a
permit
including
the
following:

°
To
address
unique
situations,
such
as
facilities
discharging
pollutants
for
which
data
are
absent
or
limited
such
that
derivation
of
technology­
or
water
quality­
based
effluent
limits
(
WQBELs)
is
difficult
or
impossible
°
To
incorporate
preventative
requirements,
such
as
requirements
to
install
process
control
alarms,
containment
structures,
good
housekeeping
practices,
etc.

°
To
address
foreseeable
changes
to
discharges,
such
as
planned
changes
to
process,
products,
or
raw
materials
that
may
affect
discharge
characteristics
°
To
incorporate
compliance
schedules
to
provide
the
time
necessary
to
comply
with
permit
conditions
NPDES
Permit
Writers'
Manual
­
137
Chapter
8
Special
Conditions
°
To
incorporate
other
NPDES
Programmatic
requirements
(
e.
g.,
pretreatment,
municipal
sewage
sludge)

°
To
impose
additional
monitoring
activities
that
provide
the
permit
writer
data
to
evaluate
the
need
for
changes
in
permit
limitations
°
To
increase
or
decrease
monitoring
requirements,
depending
on
the
monitoring
results
or
certain
changes
in
processes
or
products,
etc.

°
To
impose
requirements
to
conduct
special
studies
such
as
ambient
stream
surveys,
toxicity
reduction
evaluations
(
TREs),
bioaccumulation
studies,
sediment
studies,
mixing
or
mixing
zone
studies,
pollutant
reduction
evaluations,
or
other
such
information
gathering
studies.

Section
8.1
of
this
chapter
addresses
the
general
types
of
special
conditions
for
both
municipal
and
non­
municipal
facilities.
Special
conditions
for
storm
water
discharges
associated
with
industrial
activity
are
explained
in
Section
8.2.
Finally,

special
conditions
unique
to
POTW/
municipal
permits
are
addressed
in
Section
8.3.

8.1
General
Types
of
Special
Conditions
This
section
discusses
several
general
types
of
special
conditions
that
could
be
used
in
any
NPDES
permit
(
i.
e.,
municipal
or
non­
municipal).
The
special
conditions
include:

°
Special
studies/
additional
monitoring
°
Best
Management
Practices
(
BMPs)

°
Pollution
prevention
°
Compliance
schedules.

8.1.1
Special
Studies
and
Additional
Monitoring
Special
studies
and
additional
monitoring
requirements
imposed
beyond
those
required
under
the
effluent
limits
section
of
the
permit
are
useful
for
collecting
data
that
was
not
available
to
the
permit
writer
for
consideration
during
permit
development.

Special
studies
and
additional
monitoring
requirements
are
generally
used
to
supplement
numeric
effluent
limits
or
support
future
permit
development
activities.

138
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
Examples
of
the
types
of
special
studies
that
could
be
required
in
a
NPDES
permit
include:

°
Treatability
studies
 
Applicable
when
treatability
information
is
lacking
for
a
pollutant
or
pollutants
that
would
prohibit
a
permit
writer
from
developing
defensible
technology­
based
effluent
limits.
Treatability
studies
can
also
be
required
when
the
permit
writer
suspects
that
a
facility
may
not
be
able
to
comply
with
an
effluent
limit.

°
Toxicity
identification
evaluation/
Toxicity
reduction
evaluation
(
TIE/
TRE)
 
Required
for
facilities
for
which
wastewater
discharges
are
found
to
be
toxic
as
a
result
of
a
whole
effluent
toxicity
(
WET)
test.
The
purpose
of
these
evaluations
is
to
identify
and
control
the
sources
of
toxicity
in
an
effluent.
Further
guidance
related
to
EPA
recommended
TIE/
TRE
procedures
and
requirements
can
be
found
in
the
following
guidance
manuals:

 
Toxicity
Reduction
Evaluation
Protocol
for
Municipal
Wastewater
Treatment
Plants.
45
 
Generalized
Methodology
for
Conducting
Industrial
Toxicity
Reduction
Evaluations
(
TREs).
46
 
Methods
for
Aquatic
Toxicity
Identification
Evaluations:
Phase
I
Toxicity
Characterization
Procedures.
Second
Edition.
47
 
Sediment
Toxicity
Identification
Evaluations:
Phase
I
(
Characterization),
Phase
II
(
Identification),
Phase
III
(
Confirmation)
Modifications
of
Effluent
Procedures.
48
 
Toxicity
Identification
Evaluations:
Characterization
of
Chronically
Toxic
Effluents,
Phase
I.
49
45
USEPA
(
1989).
Toxicity
Reduction
Evaluation
Protocol
for
Municipal
Wastewater
Treatment
Plants.
EPA­
600/
4­
89­
001A.
Water
Engineering
Research
Laboratory,
Cincinnati,
Ohio.

46USEPA
(
1989).
Generalized
Methodology
for
Conducting
Industrial
Toxicity
Reduction
Evaluations
(
TREs).
EPA­
600/
2­
88­
070.
Water
Engineering
Research
Laboratory,
Cincinnati,
Ohio.

47USEPA
(
1991).
Methods
for
Aquatic
Toxicity
Identification
Evaluations:
Phase
I
Toxicity
Characterization
Procedures.
Second
Edition.
EPA­
600/
6­
91­
003.
Environmental
Research
Laboratory,
Duluth,
Minnesota.

48USEPA
(
1991).
Sediment
Toxicity
Identification
Evaluations:
Phase
I
(
Characterization),
Phase
II
(
Identification),
Phase
III
(
Confirmation)
Modifications
of
Effluent
Procedures.
EPA­
600/
6­
91­
007.
Environmental
Research
Laboratory,
Duluth,
Minnesota.

49USEPA
(
1992).
Toxicity
Identification
Evaluations:
Characterization
of
Chronically
Toxic
Effluents,
Phase
I.
EPA­
600/
6­
91­
005F.
Environmental
Research
Laboratory,
Duluth,
Minnesota.

NPDES
Permit
Writers'
Manual
­
139
Chapter
8
Special
Conditions
 
Methods
for
Aquatic
Toxicity
Identification
Evaluations:
Phase
II
Toxicity
Identification
Procedures
for
Samples
Exhibiting
Acute
and
Chronic
Toxicity.
50
 
Methods
for
Aquatic
Toxicity
Identification
Evaluations:
Phase
III
Confirmation
Procedures
for
Samples
Exhibiting
Acute
and
Chronic
Toxicity.
51
°
Mixing
or
mixing
zone
studies
 
Used
to
assist
in
determining
the
allowable
ambient
mixing
that
can
be
applied
when
developing
WQBELs.

°
Sediment
monitoring
 
Used
if
a
permit
writer
suspects
that
pollutants
contained
in
wastewater
discharges
accumulate
in
the
sediments
of
the
receiving
water.

°
Bioconcentration
studies
 
These
biological
monitoring
studies
are
used
to
determine
whether
pollutants
contained
in
wastewater
discharges
bioaccumulate
in
aquatic
organisms
(
e.
g.,
fish,
invertebrates).
These
types
of
studies
are
usually
recommended
when
WQBELs
for
pollutants
that
bioaccumulate
are
established
below
analytical
detection
levels.
Additional
guidance
related
to
evaluating
the
bioaccumulation
potential
of
a
pollutant
can
be
found
in
the
EPA
Great
Lakes
Water
Quality
Initiative
Technical
Support
Document
for
the
Procedure
to
Determine
Bioaccumulation
Factors.
52
When
establishing
special
conditions,
permit
writers
must
ensure
that
any
particular
requirements
related
to
the
study
(
e.
g.,
special
sampling
or
analytical
procedures)
are
specified
in
the
permit
condition.
In
addition,
permit
writers
must
establish
a
reasonable
schedule
for
completion
and
submission
of
the
study
or
monitoring
program.
If
the
anticipated
schedule
is
longer
than
6
months
to
1
year,

then
it
is
recommended
that
the
permit
writer
require
that
the
facility
provide
an
interim
progress
report.

50USEPA
(
1993).
Methods
for
Aquatic
Toxicity
Identification
Evaluations:
Phase
II
Toxicity
Identification
Procedures
for
Samples
Exhibiting
Acute
and
Chronic
Toxicity.
EPA­
600/
R­
92­
080.
Environmental
Research
Laboratory,
Duluth,
Minnesota.

51USEPA
(
1993).
Methods
for
Aquatic
Toxicity
Identification
Evaluations:
Phase
III
Confirmation
Procedures
for
Samples
Exhibiting
Acute
and
Chronic
Toxicity.
EPA­
600/
R­
92­
081.
Environmental
Research
Laboratory,
Duluth,
Minnesota.

52USEPA
(
1995).
Great
Lakes
Water
Quality
Initiative
Technical
Support
Document
for
the
Procedure
to
Determine
Bioaccumulation
Factors.
EPA­
820/
B­
95­
005.
Office
of
Science
and
Technology.

140
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
8.1.2
Best
Management
Practices
(
BMPs)

In
general,
BMPs
are
measures
to
prevent
or
mitigate
water
pollution
from
sources
ancillary
to
the
industrial
manufacturing
or
treatment
process.
The
NPDES
regulations,
at
40
CFR
§
122.2,
define
the
term
"
best
management
practices"
and
provide
the
following
measures
as
examples
of
BMPs:

°
Schedules
of
activities
°
Prohibitions
of
practices
°
Maintenance
procedures
°
Treatment
requirements
°
Operating
procedures
and
practices
to
control
 
Plant
site
runoff
 
Spillage
or
leaks
 
Sludge
or
waste
disposal
 
Drainage
from
raw
material
storage
areas.

The
NPDES
regulations
at
40
CFR
§
122.44(
k)
acknowledge
that
BMPs
shall
be
included
as
permit
conditions
(
when
applicable)
where
they
are
authorized
under
Section
304(
e)
of
the
CWA;
when
numeric
effluent
limitations
are
infeasible;
or
when
they
are
necessary
to
achieve
limitations
or
carry
out
the
purpose
and
intent
of
the
CWA.
Examples
of
when
numeric
effluent
limitations
are
infeasible
include:

°
Regulating
a
pollutant
for
which
limited
treatability
or
aquatic
impact
information
are
available
to
allow
development
of
technology­
based
or
water
quality­
based
effluent
limits
°
Regulating
releases
when
the
types
of
pollutants
vary
greatly
over
time.

Other
circumstances
when
BMPs
should
be
imposed
as
permit
conditions
include:

°
When
chemical
analyses
are
inappropriate
or
impossible
°
When
a
history
of
leaks
and
spills
exist
or
when
housekeeping
is
sloppy
°
When
a
complex
facility
lacks
toxic
pollutant
data
°
When
other
discharge
control
options
are
prohibitively
expensive.

Permit
writers
may
include
BMPs
in
permits
in
two
basic
ways:
require
the
development
of
a
general
BMP
plan,
and/
or
require
site­,
process­,
or
pollutant­

NPDES
Permit
Writers'
Manual
­
141
Chapter
8
Special
Conditions
specific
BMPs.
How
BMPs
are
included
as
a
permit
condition,
depends
on
the
type
of
permit
being
developed.
In
the
case
of
an
individual
permit,
where
a
permit
writer
is
developing
permit
conditions
for
a
particular
facility
and
has
the
opportunity
to
review
the
circumstances
of
the
facility,
the
development
of
site­
or
pollutant­
specific
BMPs
may
be
appropriate.
On
the
other
hand,
including
site­
or
pollutant­
specific
BMPs
as
conditions
in
a
general
permit
may
not
be
appropriate
since
they
are
highly
dependent
on
the
circumstances
of
individual
facilities.
As
a
result,
discharges
covered
under
a
general
permit
may
be
required
to
develop
a
general
BMP
plan
that
allows
the
permittee
to
determine
appropriate
BMPs
based
on
the
circumstances
of
their
particular
facility.

The
Guidance
Manual
for
Developing
Best
Management
Practices
(
BMPs)
53
describes
the
activities
and
materials
at
an
industrial
or
municipal
facility
which
are
best
addressed
by
BMP
plans.
The
manual
also
describes
how
BMPs
work
and
gives
examples
of
the
types
of
BMPs
that
can
be
used.

If
a
permit
writer
uses
a
general
permit
requirement
for
a
BMP
plan,
it
is
the
responsibility
of
the
facility
to
plan,
develop
and
implement,
and
reevaluate
the
success/
shortfalls
of
its
own
plan.
Usually,
a
BMP
committee
(
group
of
individuals
within
the
plant
organization)
is
responsible
for
developing
the
BMP
plan
and
assisting
the
plant
management
in
implementing
and
updating
the
BMP
plan.
However,
plant
management,
not
the
committee,
has
overall
responsibility
and
accountability
for
the
quality
of
the
BMP
plan.

EPA
has
identified
several
recommended
components
for
effective
BMP
plans.

The
minimum
suggested
components
of
a
general
BMP
plan
are
presented
below:

°
General
Requirements
 
Name
and
location
of
facility
 
Statement
of
BMP
policy
and
objective
 
Review
by
plant
manager
°
Specific
Requirements
 
BMP
committee
53USEPA
(
1993).
Guidance
Manual
for
Developing
Best
Management
Practices
(
BMPs).
EPA
833­
B­
93­
004.
Office
of
Water.

142
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
 
Risk
identification
and
assessment
 
Reporting
of
BMP
incidents
 
Materials
compatibility
 
Good
housekeeping
 
Preventive
maintenance
 
Inspections
and
records
 
Security
 
Employee
training.

Each
of
these
components
are
discussed
in
more
detail
in
the
Guidance
Manual
for
Developing
Best
Management
Practices
(
BMPs).
54
Site­,
process­,
and
pollutant­
specific
BMPs
are
designed
to
address
conditions
particular
to
a
site,
process,
or
pollutant.
The
need
for
specific
BMPs
at
a
facility
often
will
be
discovered
in
conjunction
with
other
permit­
related
activities,
such
as
compliance
inspections.
Poor
housekeeping
or
a
history
of
spills,
for
example,

indicate
a
need
for
specific
BMPs
to
supplement
the
quantitative
effluent
limits
for
specific
pollutants
in
the
permit.

To
select
a
specific
BMP,
the
permit
writer
must:

°
Review
the
industry
profiles
to
determine
the
industrial
processes
that
apply
°
Evaluate
whether
the
BMP
would
help
to
achieve
the
environmental
objectives
of
the
industry
°
Use
industry­
or
municipal­
specific
examples
from
other
permits,
pollution
prevention
sources,
existing
permits
for
similar
processes,
or
EPA
guidance
documents.

BMP
plans
can
be
submitted
for
review
by
the
regulatory
agency
but
are
usually
kept
onsite
and
made
available
to
the
permitting
authority
upon
request.
The
normal
compliance
schedule
is
to
require
preparation
of
the
BMP
plan
within
6
months,
and
implementation
of
the
plan
within
12
months
of
permit
issuance.

Specific
BMPs
have
been
developed
for
storm
water
discharges
and
combined
sewer
overflows
(
CSOs)
and
are
discussed
in
Sections
8.2
and
8.3,
respectively.

54USEPA
(
1993).
Guidance
Manual
for
Developing
Best
Management
Practices
(
BMPs).
EPA
833­
B­
93­
004.
Office
of
Water.

NPDES
Permit
Writers'
Manual
­
143
Chapter
8
Special
Conditions
Example:

The
following
is
example
language
for
requiring
development
and
implementation
of
a
BMP
Plan
in
an
NPDES
permit.
The
language
should
be
crafted
and
changed
as
necessary
to
meet
the
individual
facility's
needs
and
State/
EPA
goals
for
the
facility.
The
text
which
is
**
redlined**
(
i.
e.,
text
between
asterisks)
needs
special
permit­
specific
consideration.

1.
Implementation.

If
a
BMP
Plan
does
not
exist:

The
permittee,
shall
develop
and
implement
a
Best
Management
Practices
(
BMP)
Plan
which
achieves
the
objectives
and
the
specific
requirements
listed
below.
A
copy
of
the
Plan
shall
be
submitted
to
EPA
**
and/
or
State
agency.**
The
Plan
shall
be
implemented
as
soon
as
possible
but
no
later
than
twelve
months
from
the
effective
date
of
the
permit.

If
a
BMP
Plan
already
exists:

The
permittee
shall
during
the
term
of
this
permit
operate
the
facility
in
accordance
with
the
BMP
Plan
**(
cite
existing
Plan)**
or
in
accordance
with
subsequent
amendments
to
the
Plan.
The
permittee
shall
also
amend
this
Plan,
to
incorporate
practices
to
achieve
the
objectives
and
specific
requirements
listed
below,
and
a
copy
shall
be
submitted
to
EPA
**
and/
or
State
agency**
The
amended
Plan
shall
be
implemented
as
soon
as
possible
but
not
later
than
six
months
from
the
effective
date
of
the
permit.

2.
Purpose.
Through
implementation
of
the
BMP
Plan
the
permittee
shall
prevent
or
minimize
the
generation
and
the
potential
for
the
release
of
pollutants
from
the
facility
to
the
waters
of
the
United
States
through
normal
operations
and
ancillary
activities.

3.
Objectives.
The
permittee
shall
develop
and
amend
the
BMP
Plan
consistent
with
the
following
objectives
for
the
control
of
pollutants.

a.
The
number
and
quantity
of
pollutants
and
the
toxicity
of
effluent
generated,
discharged
or
potentially
discharged
at
the
facility
shall
be
minimized
by
the
permittee
to
the
extent
feasible
by
managing
each
influent
waste
stream
in
the
most
appropriate
manner.

b.
Under
the
BMP
Plan,
and
any
Standard
Operating
Procedures
(
SOPs)
included
in
the
Plan,
the
permittee
shall
ensure
proper
operation
and
maintenance
of
the
treatment
facility.

c.
The
permittee
shall
establish
specific
objectives
for
the
control
of
pollutants
by
conducting
the
following
evaluations.

(
1)
Each
facility
component
or
system
shall
be
examined
for
its
waste
minimization
opportunities
and
its
potential
for
causing
a
release
of
significant
amounts
of
pollutants
to
waters
of
the
United
States
due
to
equipment
failure,
improper
operation,
and
natural
phenomena
such
as
rain
or
snowfall,
etc.
The
examination
shall
include
all
normal
operations
and
ancillary
activities
including
material
storage
areas,
plant
site
runoff,
in­
plant
transfer,
process
and
material
handling
areas,
loading
or
unloading
operations,
spillage
or
leaks,
sludge
and
waste
disposal,
or
drainage
from
raw
material
storage.
**
note
that
only
the
area
from
the
previous
list
which
apply
to
a
facility
should
be
included**

(
2)
Where
experience
indicates
a
reasonable
potential
for
equipment
failure
(
e.
g.,
a
tank
overflow
or
leakage),
natural
condition
(
e.
g.,
precipitation),
or
other
circumstances
to
result
in
significant
amounts
of
pollutants
reaching
surface
waters,
the
program
should
include
a
prediction
of
the
direction,
rate
of
flow
and
total
quantity
of
pollutants
which
could
be
discharged
from
the
facility
as
a
result
of
each
condition
or
circumstance.

144
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
Example
(
continued):

4.
Requirements.
The
BMP
Plan
shall
be
consistent
with
the
objectives
in
Part
3
above
and
the
general
guidance
contained
in
the
publication
entitled
Guidance
Manual
for
Developing
Best
Management
Practices
(
BMPs)(
USEPA,
1993)
or
any
subsequent
revisions
to
the
guidance
document.
The
BMP
Plan
shall:

a.
Be
documented
in
narrative
form,
shall
include
any
necessary
plot
plans,
drawings
or
maps,
and
shall
be
developed
in
accordance
with
good
engineering
practices.
The
BMP
Plan
shall
be
organized
and
written
with
the
following
structure:

(
1)
Name
and
location
of
the
facility.

(
2)
Statement
of
BMP
policy.

(
3)
Structure,
functions,
and
procedures
of
the
BMP
Committee.

(
4)
Specific
management
practices
and
standard
operating
procedures
to
achieve
the
above
objectives,
including,
but
not
limited
to,
the
following:

(
a)
modification
of
equipment,
facilities,
technology,
processes,
and
procedures,
(
b)
reformulation
or
redesign
of
products,
(
c)
substitution
of
materials,
and
(
d)
improvement
in
management,
inventory
control,
materials
handling
or
general
operational
phases
of
the
facility.

(
5)
Risk
identification
and
assessment.

(
6)
Reporting
of
BMP
incidents.

(
7)
Materials
compatibility.

(
8)
Good
housekeeping.

(
9)
Preventative
maintenance.

(
10)
Inspections
and
records.

(
11)
Security.

(
12)
Employee
training.

b.
Include
the
following
provisions
concerning
BMP
Plan
review:

(
1)
Be
reviewed
by
plant
engineering
staff
and
the
plant
manager.

(
2)
Be
reviewed
and
endorsed
by
the
permittee's
BMP
Committee.

(
3)
Include
a
statement
that
the
above
reviews
have
been
completed
and
that
the
BMP
Plan
fulfills
the
requirements
set
forth
in
this
permit.
The
statement
shall
be
certified
by
the
dated
signatures
of
each
BMP
Committee
member.

c.
Establish
specific
best
management
practices
to
meet
the
objectives
identified
in
Part
3
of
this
section,
addressing
each
component
or
system
capable
of
generating
or
causing
a
release
of
significant
amounts
of
pollutants,
and
identifying
specific
preventative
or
remedial
measures
to
be
implemented.

NPDES
Permit
Writers'
Manual
­
145
Chapter
8
Special
Conditions
8.1.3
Pollution
Prevention
Example
(
continued):

d.
Establish
specific
best
management
practices
or
other
measures
which
ensure
that
the
following
specific
requirements
are
met:

(
1)
Ensure
proper
management
of
solid
and
hazardous
waste
in
accordance
with
regulations
promulgated
under
the
Resource
Conservation
and
Recovery
Act
(
RCRA).
Management
practices
required
under
RCRA
regulations
shall
be
referenced
in
the
BMP
Plan.

(
2)
Reflect
requirements
for
Spill
Prevention,
Control,
and
Countermeasure
(
SPCC)
plans
under
Section
311
of
the
Act
and
40
CFR
Part
112
and
may
incorporate
any
part
of
such
plans
into
the
BMP
Plan
by
reference.

(
3)
Reflect
requirements
for
storm
water
control
under
Section
402(
p)
of
the
Act
and
the
regulations
at
40
CFR
122.26
and
122.44,
and
otherwise
eliminate
to
the
extent
practicable,
contamination
of
storm
water
runoff.

(
4),
etc.

**
Section
4.
d.
needs
to
be
tailored
to
each
facility
by
the
permit
writer.
Processes
or
areas
of
the
facility
with
housekeeping
problems,
noncompliance,
spills/
leaks,
or
other
problems
which
could
be
remedied
through
a
BMP
should
be
addressed
here.
If
a
solution
to
the
problem
is
known
(
e.
g.,
more
frequent
inspections,
preventive
maintenance,
etc.)
this
remedy
should
also
be
included
as
a
part
of
the
BMP
Plan
requirements.
To
gather
ideas
for
such
requirements,
the
permit
writer
may
want
to
contact
the
permittee,
compliance
personnel,
facility
inspectors,
operations
office
personnel,
State
agency
counterparts.
The
permit
writer
may
also
want
to
check
requirements
in
other
permits
and
BMP
Plans
for
similar
facilities.**

5.
Documentation.
The
permittee
shall
maintain
a
copy
of
the
BMP
Plan
at
the
facility
and
shall
make
the
plan
available
to
EPA
**
and/
or
State
agency**
upon
request.
All
offices
of
the
permittee
which
are
required
to
maintain
a
copy
of
the
NPDES
permit
shall
also
maintain
a
copy
of
the
BMP
Plan.

6.
BMP
Plan
Modification.
The
permittee
shall
amend
the
BMP
Plan
whenever
there
is
a
change
in
the
facility
or
in
the
operation
of
the
facility
which
materially
increases
the
generation
of
pollutants
or
their
release
or
potential
release
to
the
receiving
waters.
The
permittee
shall
also
amend
the
Plan,
as
appropriate,
when
plant
operations
covered
by
the
BMP
Plan
change.
Any
such
changes
to
the
BMP
Plan
shall
be
consistent
with
the
objectives
and
specific
requirements
listed
above.
All
changes
in
the
BMP
Plan
shall
be
reported
to
EPA
**
and/
or
State
agency**
in
writing.

7.
Modification
for
Ineffectiveness.
At
any
time,
if
the
BMP
Plan
proves
to
be
ineffective
in
achieving
the
general
objective
of
preventing
and
minimizing
the
generation
of
pollutants
and
their
release
and
potential
release
to
the
receiving
waters
and/
or
the
specific
requirements
above,
the
permit
and/
or
the
BMP
Plan
shall
be
subject
to
modification
to
incorporate
revised
BMP
requirements.

Pollution
prevention
has
been
shown
to
reduce
costs
as
well
as
pollution
risks
through
source
reduction
and
recycling/
reuse
techniques.
Under
Section
6602(
b)
of
the
Pollution
Prevention
Act
of
1990,
Congress
established
a
national
policy
for
a
hierarchy
of
environmental
management:

°
Pollution
should
be
prevented
or
reduced
at
the
source,
whenever
feasible.

°
Pollution
that
cannot
be
prevented
should
be
recycled
in
an
environmentally
safe
manner,
whenever
feasible.

146
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
°
Pollution
that
cannot
be
prevented
or
recycled
should
be
treated
in
an
environmentally
safe
manner,
whenever
feasible.

°
Disposal
or
other
release
into
the
environment
should
be
employed
only
as
a
last
resort
and
should
be
conducted
in
an
environmentally
safe
manner.

The
Pollution
Prevention
Act
emphasizes
that
pollution
prevention
means
source
reduction
and
defines
source
reduction
as
any
practice
that:

°
Reduces
the
amount
of
any
hazardous
substance,
pollutant,
or
contaminant
entering
any
waste
stream
or
otherwise
released
into
the
environment
(
including
fugitive
emissions)
prior
to
recycling,
treatment,
or
disposal
°
Reduces
the
threats
to
public
health
and
the
environment
associated
with
the
release
of
hazardous
substances,
pollutants,
or
contaminants
°
Increases
the
efficiency
of
using
raw
materials,
energy,
water,
or
other
resources,
or
protects
natural
resources
by
conservation.

The
environmental
management
hierarchy
 
prevention,
recycling,
treatment,

and
disposal
 
should
be
viewed
as
establishing
a
set
of
preferences,
rather
than
an
absolute
judgment
that
prevention
is
always
the
most
desirable
option.
The
hierarchy
is
applied
to
many
different
circumstances
that
require
good
judgment.
Prevention
includes
what
is
commonly
called
in­
process
recycling.
Recycling
conducted
in
an
environmentally
sound
manner
shares
many
of
the
advantages
of
prevention
(
e.
g.,

energy
and
resource
conservation
and
reduction
of
the
need
for
end­
of­
pipe
treatment
or
waste
containment).

Within
the
NPDES
Program,
BMPs
are
inherently
pollution
prevention
practices.

Traditionally,
BMPs
have
focused
on
good
housekeeping
measures
and
good
management
techniques
that
attempt
to
avoid
contact
between
pollutants
and
water
media
as
a
result
of
leaks,
spills,
and
improper
waste
disposal.
However,
based
on
the
authority
granted
under
the
regulations,
BMPs
may
include
the
universe
of
pollution
prevention,
which
encompasses
production
modifications,
operational
changes,
materials
substitution,
materials
and
water
conservation,
and
other
such
measures.

NPDES
Permit
Writers'
Manual
­
147
Chapter
8
Special
Conditions
8.1.4
Compliance
Schedules
The
NPDES
regulations
at
40
CFR
§
122.47
allow
permit
writers
to
include
schedules
of
compliance
to
allow
permittees
additional
time
to
achieve
compliance
with
the
CWA
and
applicable
regulations.
Schedules
developed
under
this
provision
must
require
compliance
by
the
permittee
as
soon
as
possible,
but
may
not
extend
the
date
for
final
compliance
beyond
compliance
dates
established
by
the
Act.
Examples
of
situations
where
compliance
schedules
may
be
appropriate
include:

°
Pretreatment
program
development
°
Sludge
use
and
disposal
program
development
and/
or
implementation
°
New/
revised
effluent
guidelines
application
°
New/
revised
water
quality
standards
application
°
BMP
plan
development
and/
or
implementation
°
Storm
water,
CSO
and/
or
SSO
control
program
development
and/
or
implementation.

While
compliance
schedules
may
be
appropriate
for
implementation
of
certain
NPDES
Program
requirements,
they
are
not
appropriate
for
requirements
where
statutory
deadlines
have
passed.
In
particular,
compliance
schedules
are
not
appropriate
under
the
following
scenarios:

1.
Compliance
with
Technology­
Based
Effluent
Limits
Compliance
schedules
are
not
allowed
at
this
time
because
statutory
deadlines
have
passed
for
BPT,
BAT,
and
BCT
levels
of
treatment.

°
July
1,
1977
for
BPT
°
March
31,
1989
for
BAT
and
BCT.

This
applies
to
both
existing
and
new
dischargers.
It
should
be
noted,
however,
that
40
CFR
§
122.29(
d)(
4)
allows
a
new
source
or
new
discharger
up
to
90
days
to
"
start­
up"
its
pollution
control
equipment
and
achieve
compliance
with
its
permit
conditions
(
i.
e.,
provides
for
up
to
a
90­
day
period
to
achieve
compliance).

2.
Compliance
with
Water
Quality­
Based
Effluent
Limits
The
determination
of
whether
a
compliance
schedule
to
meet
water
qualitybased
permit
limits
is
permissible
depends
on
when
the
applicable
State
water
148
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
quality
standards
were
initially
promulgated.
Because
States
were
required
to
have
water
quality
standards
promulgated
by
July
1,
1977,
and
because
facilities
were
supposed
to
have
had
the
opportunity
to
comply
with
the
standards,
compliance
schedules
are
not
allowed
if
the
State
water
quality
standards
were
promulgated
before
July
1,
1977.

If
a
State
promulgates
a
water
quality
standards
after
July
1,
1977,
and
if
the
State
water
quality
regulations
allow
for
a
compliance
schedule
to
comply
with
the
standards,
then
a
compliance
schedule
could
be
granted
in
accordance
with
40
CFR
47.

If
a
State
promulgates
a
water
quality
standards
after
July
1,
1977,
and
the
State
water
quality
regulations
do
not
allow
for
a
compliance
schedule
to
comply
with
the
standards,
then
a
compliance
schedule
may
not
be
granted.

[
See:
Star­
Kist
Caribe,
Inc.,
NPDES
Appeal
No.
88­
5]

In
situations
where
the
permittee
will
be
unable
to
meet
permit
conditions,
and
where
a
compliance
schedule
pursuant
to
40
CFR
§
122.47
is
not
permitted,
the
practical
alternative
is
to
initiate
an
Administrative
Order
under
Section
309
of
the
CWA
(
containing
a
schedule
of
compliance)
concurrent
with
permit
issuance.

8.2
Permit
Conditions
Addressing
Storm
Water
Discharges
Associated
With
Industrial
Activities
As
previously
discussed
in
Chapter
2,
all
storm
water
discharges
associated
with
industrial
activity
that
discharge
storm
water
through
a
separate
municipal
storm
sewer
system
(
MS4)
or
discharge
directly
to
waters
of
the
United
States
are
required
to
obtain
NPDES
permit
coverage.
Following
the
promulgation
of
the
November
16,

1990,
storm
water
application
regulations,
EPA
and
NPDES
authorized
States
were
faced
with
providing
permit
coverage
for
storm
water
discharges
from
over
100,000
industrial
facilities.
Due
to
the
nature
of
the
discharge
(
i.
e.,
storm
water)
and
the
large
number
of
facilities
requiring
permit
coverage,
EPA
and
most
NPDES
authorized
States
chose
to
use
general
permits
as
a
mechanism
to
provide
permit
coverage
for
facilities
requiring
permit
coverage
for
their
storm
water
discharges.

Unlike
discharges
of
process
wastewater
where
numerical
effluent
limitations
(
technology­
based
and/
or
water
quality­
based)
are
typically
used
to
control
the
discharge
of
pollutants
from
industrial
facilities,
the
primary
permit
condition
used
to
NPDES
Permit
Writers'
Manual
­
149
Chapter
8
Special
Conditions
address
discharges
of
pollutants
in
a
facilities
storm
water
is
a
pollution
prevention
plan.
The
development
and
implementation
of
a
site­
specific
storm
water
pollution
prevention
plan
is
considered
to
be
the
most
important
requirement
of
the
EPA
and
State
issued
storm
water
general
permits.
Site­
specific
storm
water
pollution
prevention
plans
allow
permittees
to
develop
and
implement
"
best
management
practices",
whether
structural
or
non­
structural,
that
are
best
suited
for
controlling
storm
water
discharges
from
their
industrial
facility.

Each
industrial
facility
covered
under
an
EPA
issued
storm
water
general
permit
must
develop
a
pollution
prevention
plan,
tailored
to
the
site
specific
conditions,
and
designed
with
the
goal
to
control
the
amount
of
pollutants
in
storm
water
discharges
from
the
site.
The
special
conditions
component
of
EPA's
storm
water
general
permits
identify
the
requirements
that
each
facility
must
include
in
their
storm
water
pollution
prevention
plan,
including:

°
A
description
of
potential
pollutant
sources
at
the
facility,
including:

 
A
map
of
the
facility
indicating
the
drainage
areas
of
the
site
and
the
industrial
activities
which
occur
in
each
drainage
area
 
An
inventory
of
materials
that
may
be
exposed
to
storm
water
 
A
description
of
the
likely
sources
of
pollutants
from
the
site
and
a
prediction
of
the
pollutants
which
are
likely
to
be
present
in
the
storm
water
 
The
history
of
spills
and
leaks
of
toxic
and
hazardous
materials
over
the
last
three
years
°
The
measures
and
controls
that
will
be
implemented
to
prevent
or
minimize
pollution
of
storm
water,
including:

 
Good
housekeeping
or
upkeep
of
industrial
areas
exposed
to
storm
water
 
Preventative
maintenance
of
storm
water
controls
and
other
facility
equipment
 
Spill
prevention
and
response
procedures
 
Testing
of
outfalls
to
ensure
that
there
are
no
illicit
discharges
 
Employee
training
on
pollution
prevention
measure
and
controls,
and
record
keeping.

A
permit
writer's
best
source
of
information
for
developing
appropriate
special
conditions
for
storm
water
controls
are
perhaps
other
storm
water
general
permits.

Using
existing
general
permits
as
the
basis
for
special
conditions
is
encouraged
since
150
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
this
will
reduce
duplication
of
efforts.
A
listing
of
all
general
permits
(
storm
water
and
non­
storm
water)
issued
by
EPA
as
well
as
authorized
States,
which
can
be
used
as
a
permit
writing
resource,
can
be
found
in
the
EPA
Point
Source
Information
Provision
Exchange
System
(
PIPES)
accessible
through
EPA's
World
Wide
Web
home
page
[
http:/
www.
epa.
gov].
In
addition,
EPA
has
developed
the
following
guidance
documents
to
help
permit
writers
identify
components
of
storm
water
pollution
prevention
plans
as
well
as
to
assist
permittees
in
developing
plans:

°
Storm
Water
Management
for
Industrial
Activities:
Developing
Pollution
Prevention
Plans
and
Best
Management
Practices.
55
°
Storm
Water
Management
for
Construction
Activities:
Developing
Pollution
Prevention
Plans
and
Best
Management
Practices.
56
8.3
Special
Conditions
for
Municipal
Facilities
This
section
explains
several
common
special
conditions
that
are
applicable
only
to
municipal
facilities.
These
conditions
reflect
requirements
for
POTWs
to
implement
and
enforce
local
pretreatment
programs
for
their
industrial
users;
sludge
disposal
requirements;
CSO
requirements;
SSO
requirements;
and
MS4
requirements.

8.3.1
The
National
Pretreatment
Program
Section
402(
b)(
8)
of
the
CWA
requires
that
POTWs
receiving
pollutants
from
significant
industrial
sources
subject
to
section
307(
b)
standards
establish
a
POTW
pretreatment
program
to
ensure
compliance
with
these
standards.
The
implementing
regulations
at
40
CFR
403.8(
a)
state,
"
any
POTW
(
or
combination
of
POTWs
operated
by
the
same
authority)
with
a
total
design
flow
greater
than
5
million
gallons
per
day
(
mgd)
and
receiving
from
industrial
users
pollutants
which
pass
through
or
interfere
with
the
operation
of
the
POTW
or
are
otherwise
subject
to
pretreatment
standards
will
be
required
to
establish
a
POTW
pretreatment
program
unless
the
NPDES
State
exercises
its
option
to
assume
local
responsibilities
as
provided
in
403.10(
e)."
EPA
or
a
NPDES
State
with
an
approved
pretreatment
program
may
require
POTWs
with
55USEPA
(
1992).
Storm
Water
Management
for
Industrial
Activities:
Developing
Pollution
Prevention
Plans
and
Best
Management
Practices.
EPA
832­
R­
92­
006.
Office
of
Water.

56USEPA
(
1992).
Storm
Water
Management
for
Construction
Activities:
Developing
Pollution
Prevention
Plans
and
Best
Management
Practices.
EPA
832­
R­
92­
005.

NPDES
Permit
Writers'
Manual
­
151
Chapter
8
Special
Conditions
design
flows
of
5
mgd
or
less
to
develop
a
POTW
pretreatment
program
if
circumstances
warrant
(
40
CFR
403.8(
a)).
The
requirement
to
develop
a
pretreatment
program
only
applies
to
POTWs
or
States
using
the
option
under
403.10(
e),
this
is
primarily
due
to
the
fact
that
the
pretreatment
regulations
at
40
CFR
403
only
apply
to
POTWs
and
industrial
users
of
POTWs,
and
the
State
or
EPA
offices
that
issue
permits
to
the
POTWs.

Since
1978,
approximately
1,500
POTWs
have
been
required
to
develop
and
implement
pretreatment
programs
as
special
conditions
of
NPDES
permits.
The
pretreatment
program
was
developed
to
control
industrial
discharges
to
POTWs
and
to
meet
three
objectives
at
the
POTWs:
(
1)
to
prevent
pass
through,
(
2)
to
prevent
interference,
including
interference
with
its
use
or
disposal
of
municipal
sludge,
(
3)
to
improve
opportunities
to
recycle
and
reclaim
municipal
and
industrial
wastewater
and
sludges.

As
authorized
by
the
pretreatment
regulations
at
40
CFR
403.8(
c),(
d)
and
(
e)

and
the
NPDES
regulations
at
40
CFR
122.44(
j)(
2),
the
requirements
to
develop
and
implement
a
POTW
pretreatment
program
are
placed
as
enforceable
conditions
in
the
POTW's
NPDES
permit.

Pretreatment
Program
development
and
Program
Implementation
are
done
as
two
separate
steps.
Through
the
NPDES
permit
the
POTW
is
required
to
develop
a
Pretreatment
Program.
The
POTW
is
required
to
submit
an
approvable
program
that
meets
the
requirements
in
40
CFR
403.9(
b),
specifically,
these
requirements
are
the
provisions
of
a
program
as
laid
out
in
40
CFR
403.8(
f).
40
CFR
403.8(
f)
requires
the
POTW
to
have
certain
legal
authority
(
usually
a
municipal
ordinance
or
set
of
regulations)
and
procedures
to
fully
and
effectively
exercise
and
implement
the
legal
authority
and
procedures.
The
POTW
must
submit
a
program
detailing
the
legal
authority
to:

1.
Deny
or
condition
new
or
increased
contributions
of
pollutants,
or
changes
in
nature
of
pollutants,
to
the
POTW
by
industrial
users;

2.
Require
compliance
with
applicable
pretreatment
standards
and
requirements
by
industrial
users;

152
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
3.
Control
through
permit,
order,
or
similar
means
the
contribution
to
the
POTW
by
each
industrial
user
to
ensure
compliance
with
applicable
pretreatment
standards
and
requirements.
These
control
mechanisms
must
have
certain
conditions
as
laid
out
in
403.8(
f)(
1)(
iii)
and
be
enforceable;

4.
Require
the
development
of
compliance
schedules
where
necessary
by
each
industrial
user
for
the
installation
of
technology
required
to
meet
applicable
pretreatment
standards
and
requirements,
and
submission
of
all
notices
and
self­
monitoring
reports
to
assess
and
ensure
compliance;

5.
Carry
out
all
inspection,
surveillance,
and
monitoring
procedures
necessary
to
determine
compliance
with
applicable
pretreatment
standards
and
requirements
independent
of
information
submitted
by
the
industrial
user
(
this
will
include
authority
to
enter
the
premises
of
the
industrial
user);

6.
Obtain
remedies
for
noncompliance
(
e.
g.,
injunctive
relief,
penalties);

7.
Comply
with
confidentiality
requirements.

Further
at
a
minimum,
the
POTW
must
have
procedures
to:

1.
Identify
and
locate
all
possible
industrial
users
which
might
be
subject
to
the
POTW
pretreatment
program;

2.
Identify
the
character
and
volume
of
pollutants
contributed
to
the
POTW
by
the
industrial
users;

3.
Notify
industrial
users
of
applicable
pretreatment
standards
and
applicable
requirements
under
section
204(
b)
and
405
of
the
Clean
Water
Act
and
subtitles
C
and
D
of
RCRA;

4.
Receive
and
analyze
self
monitoring
reports;

5.
Conduct
sampling,
inspections
and
other
surveillance
activities
to
determine
compliance
with
applicable
pretreatment
standards
and
requirements
independent
of
information
supplied
by
the
industrial
user;

6.
Investigate
instances
of
noncompliance;
and
7.
Comply
with
public
participation,
including
public
notice
annually
of
industrial
users
determined
to
be
in
significant
noncompliance
during
the
previous
12­
month
period.

NPDES
Permit
Writers'
Manual
­
153
Chapter
8
Special
Conditions
Also,
as
part
of
the
POTW
pretreatment
program,
POTWs
must
have
adequate
resources
and
funding
to
implement
the
program,
evaluate
the
need
for
local
limits
and
develop
them
if
the
need
exists,
and
develop
an
enforcement
response
plan.

The
permit
requires
the
POTW
to
submit
the
program
documentation
which
details
the
authority
and
procedures
to
be
implemented
along
with
other
information
about
the
program
as
laid
out
in
40
CFR
403.9.
The
permit
will
allow
the
POTW
up
to
one
year
from
the
time
the
permitting
authority
determines
the
need
for
a
pretreatment
program
exists
to
develop
and
submit
a
program
for
approval.
Once
the
permitting
authority
reviews
and
approves
the
program,
the
program
is
then
incorporated
into
the
permit
in
order
to
make
the
requirement
to
implement
the
program
an
enforceable
part
of
the
permit.

The
incorporation
of
the
requirement
to
develop
a
pretreatment
is
generally
done
at
the
time
of
reissuance
of
the
permit.
However,
the
requirement
may
also
be
incorporated
through
a
modification
of
the
permit
if
cause
exists.
Cause
exists
if
"...

the
addition
of
pollutants
into
POTW
by
an
industrial
user
or
combination
of
industrial
users
presents
a
substantial
hazard
to
the
functioning
of
the
treatment
works,
quality
of
the
receiving
waters,
human
health,
or
the
environment,"
(
40
CFR
403.8(
e)(
1)).

A
permit
modification
to
require
the
development
of
a
pretreatment
program
is
considered
a
major
modification
and
must
follow
the
procedures
in
40
CFR
122.62.

The
incorporation
of
an
approved
program
into
the
permit,
thereby
making
the
implementation
of
the
program
an
enforceable
part
of
the
permit,
is
considered
a
minor
modification
to
the
permit
and
must
follow
the
procedures
in
40
CFR
122.63(
g).

During
the
life
of
the
permit
it
may
be
necessary
for
the
POTW
to
modify
its
approved
pretreatment
program
(
changes
to
local
limits,
changes
to
the
ordinance,
etc.).
These
changes
may
be
brought
about
by
the
POTW's
desire
to
change
the
way
the
program
operates,
or
they
may
be
the
result
of
changes
that
are
necessary
to
address
deficiencies
in
the
program
found
during
inspections
or
audits
done
by
the
permitting
authority.
Whatever
the
reason
for
the
modification,
these
modifications
to
the
approved
program
require
review
and
approval
by
the
permitting
authority
(
Approval
Authority)
when
the
modifications
are
considered
substantial,
per
40
CFR
403.18.
All
approved
substantial
program
modifications
to
the
POTW's
approved
pretreatment
program
require
minor
modifications
to
the
permit.

154
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
Most
of
the
POTWs
who
need
pretreatment
program
requirements
in
their
Regulatory
Update
As
of
December
1996,
there
are
two
proposed
regulations
that
may
impact
the
permitting
requirements
for
POTWs
with
pretreatment
programs.
First
is
the
regulation
that
defines
a
substantial
pretreatment
program
modification.
EPA
is
reconsidering
the
definition
of
what
is
a
substantial
modification.
EPA
has
proposed
to
shorten
the
list
and
thereby
reduce
the
need
for
minor
permit
modifications.
Second,
EPA
has
proposed
a
new
regulation
for
POTWs
to
apply
for
NPDES
permits.
The
current
regulations
require
POTWs
to
submit
an
evaluation
of
the
need
for
local
limits
with
their
NPDES
permit
application.
The
proposed
regulation
would
require
the
evaluation
to
be
submitted
after
the
permit
has
been
reissued.
Therefore
the
permit
will
need
to
have
language
included
that
implements
this
requirement.

permits
currently
have
them
in
place.
EPA
Regions
and
approved
States
have
developed
standard
pretreatment
development
or
implementation
conditions
(
with
minor
modifications
made
to
tailor
the
conditions
to
the
specific
permittee)
that
are
placed
in
all
pretreatment
POTW
NPDES
permits
in
that
Region
or
State.
The
permit
writer
can
obtain
examples
of
these
NPDES
pretreatment
conditions
from
the
EPA
or
State
pretreatment
coordinators.
The
permit
writer
may
need
to
update
or
modify
pretreatment
implementation
language
or
initiate
corrective
action
related
to
the
pretreatment
program.

A
NPDES
State
or
an
EPA
Region
will
often
designate
a
pretreatment
coordinator
to
serve
as
the
pretreatment
expert
to
review
the
annual
report
from
the
POTW
and
recommend
any
action
to
be
taken.
The
State
or
EPA
Regional
pretreatment
coordinator
is
a
key
resource
on
pretreatment
issues,
particularly
at
the
time
of
NPDES
permit
reissuance.
EPA
has
prepared
a
number
of
guidance
manuals
for
POTWs
on
how
to
implement
their
local
pretreatment
programs.

Pretreatment
program
information
and
monitoring
data
obtained
through
the
POTW's
pretreatment
program
may
be
useful
to
the
permit
writer
in
identifying
possible
modifications
to
the
pretreatment
program's
local
limits
or
procedures,
or
the
need
for
water
quality­
based
controls.
Although
there
is
currently
no
requirement
for
chemical­
specific
toxics
effluent
monitoring
to
be
submitted
with
the
permit
application,

most
pretreatment
POTWs
have
performed
toxics
monitoring
of
their
influent,
effluent,

and
sludge.
The
permit
writer
should
obtain
such
data
with
the
aid
of
the
pretreatment
coordinator.
These
data
can
be
used
to
determine
the
need
for
water
quality­
based
limits.

NPDES
Permit
Writers'
Manual
­
155
Chapter
8
Special
Conditions
8.3.2
Municipal
Sewage
Sludge
Section
405(
d)
of
the
CWA
requires
that
EPA
regulate
the
use
and
disposal
of
sewage
sludge
to
protect
public
health
and
the
environment
from
any
reasonably
anticipated
adverse
effects
of
these
practices.
In
the
CWA,
Congress
directs
EPA
to
develop
technical
standards
for
municipal
sludge
use
and
disposal
options.
These
standards
are
set
out
in
40
CFR
Part
503.
Congress
also
enacted
strict
deadlines
for
compliance
with
these
standards.
Within
1
year
of
promulgation
of
the
standards,

compliance
was
required
unless
construction
of
new
pollution
control
facilities
was
necessary,
in
which
case
compliance
was
required
within
2
years.

EPA
promulgated
the
40
CFR
Part
503
Standards
for
the
Use
or
Disposal
of
Sewage
Sludge
on
February
19,
1993
(
58
FR
9248)
with
amendments
on
February
19,
1994
(
59
FR
9095)
and
October
25,
1995
(
60
FR
54764).
These
regulations
address
four
sludge
use
and
disposal
practices:
land
application,
surface
disposal,

incineration,
and
disposal
in
a
municipal
solid
waste
landfill.
The
standards
for
each
end
use
and
disposal
method
consist
of
general
requirements,
numeric
pollutant
limits,
operational
standards,
and
management
practices,
as
well
as
monitoring,

recordkeeping,
and
reporting
requirements.
Unlike
technology
standards
based
on
the
ability
of
treatment
technologies
to
reduce
the
level
of
pollutants,
EPA's
sewage
sludge
standards
are
based
on
health
and
environmental
risks.

40
CFR
Part
503
imposes
requirements
on
four
groups:

°
Persons
who
prepare
sewage
sludge
or
material
derived
from
sewage
sludge
°
Land
appliers
of
sewage
sludge
°
Owners/
operators
of
sewage
sludge
surface
disposal
sites
°
Owners/
operators
of
sewage
sludge
incinerators.

The
regulation
is
largely
self­
implementing.
This
means
that
anyone
engaged
in
activities
covered
by
the
regulation
must
comply
with
the
appropriate
requirements
on
or
before
the
compliance
deadlines.
A
person
who
violates
40
CFR
Part
503
requirements
is
subject
to
administrative,
civil,
and/
or
criminal
enforcement
actions.

156
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
Section
405(
f)
of
the
CWA
requires
the
inclusion
of
sewage
sludge
use
or
disposal
requirements
in
any
NPDES
permit
issued
to
a
Treatment
Works
Treating
Domestic
Sewage
(
TWTDS)
and
authorizes
the
issuance
of
sewage
sludge
permits
to
non­
discharging
TWTDS.
To
provide
a
mechanism
for
this
inclusion,
EPA
promulgated
revisions
to
the
NPDES
permit
regulations
at
40
CFR
Parts
122
and
124
on
May
2,
1989
(
54
FR
18716).
These
revisions
expanded
EPA's
authority
to
include
sewage
sludge
use
and
disposal
standards
in
NPDES
permits
and
to
issue
NPDES
permits
to
treatment
works
that
do
not
have
an
effluent
discharge
to
waters
of
the
United
States,
but
are
involved
in
sewage
sludge
use
or
disposal
as
preparers,

appliers,
or
owners/
operators.
TWTDS
includes
all
sewage
sludge
generators
and
facilities
that
change
the
quality
of
sewage
sludge
such
as
blenders.

EPA
recognizes
that
implementation
of
40
CFR
Part
503
requirements
is
a
source
of
confusion
for
permit
writers
and
permittees
who
may
already
have
NPDES
permits
with
sewage
sludge
special
conditions.
The
end
result
is
that
both
NPDES
sludge
permit
conditions
and
40
CFR
Part
503
requirements
apply.
EPA
expects
that
over
time,
all
NPDES
sludge
requirements
will
be
revised
to
include
the
40
CFR
Part
503
requirements.
To
reduce
confusion,
EPA
has
provided
several
guidance
documents
to
explain
the
requirements
of
40
CFR
Part
503.

°
Part
503
Implementation
Guidance.
57
°
Land
Application
of
Sewage
Sludge
 
A
Guide
for
Land
Appliers
on
the
Recordkeeping
and
Reporting
Requirements
of
the
Federal
Standards
for
the
Use
and
Disposal
of
Sewage
Sludge
Management
in
40
CFR
Part
503.58
°
Surface
Disposal
of
Sewage
Sludge
 
A
Guide
for
Owners/
Operators
of
Surface
Disposal
Facilities
on
the
Monitoring,
Recordkeeping,
and
Reporting
Requirements
of
the
Federal
Standards
for
the
Use
and
Disposal
of
Sewage
Sludge
in
40
CFR
Part
503.59
57USEPA
(
1995).
Part
503
Implementation
Guidance.
EPA
833­
R­
95­
001.
Office
of
Water.

58USEPA
(
1994).
Land
Application
of
Sewage
Sludge
 
A
Guide
for
Land
Appliers
on
the
Recordkeeping
and
Reporting
Requirements
of
the
Federal
Standards
for
the
Use
and
Disposal
of
Sewage
Sludge
Management
in
40
CFR
Part
503.
EPA­
831/
B­
93­
002c.
Office
of
Water.

59USEPA
(
1994).
Surface
Disposal
of
Sewage
Sludge
 
A
Guide
for
Owner/
Operators
of
Surface
Disposal
Facilities
on
the
Monitoring,
Record
Keeping,
and
Reporting
Requirements
of
the
Federal
Standards
for
the
Use
and
Disposal
of
Sewage
Sludge
in
40
CFR
Part
503.
EPA­
831/
B­
93­
002b.
Office
of
Water.

NPDES
Permit
Writers'
Manual
­
157
Chapter
8
Special
Conditions
°
Preparing
Sewage
Sludge
for
Land
Application
or
Surface
Disposal
 
A
Guide
for
Preparers
of
Sewage
Sludge
on
the
Monitoring,
Record
Keeping,
and
Reporting
Requirements
of
the
Federal
Standards
for
the
Use
or
Disposal
of
Sewage
Sludge
in
40
CFR
Part
503.60
°
Domestic
Septage
Regulatory
Guidance,
A
Guide
to
the
EPA
503
Rule.
61
°
Control
of
Pathogens
and
Vector
Attraction
in
Sewage
Sludge.
62
The
permit
writer
should
refer
to
the
Part
503
Implementation
Guidance63
and
EPA
Region
and
State
guidelines
or
policies
for
instructions
on
how
to
implement
the
applicable
40
CFR
Part
503
standards
into
the
permit.
The
permit
writer
will
need
to
determine
the
type
of
sludge
use
or
disposal
practice(
s)
used
by
the
permittee
and
apply
the
appropriate
40
CFR
Part
503
standards.
In
general,
conditions
will
need
to
be
established
to
address:

°
Pollutant
concentrations
or
loading
rates
°
Operational
standards
(
such
as
pathogen
and
vector
attraction
reduction
requirements
for
land
application
and
surface
disposal
and
total
hydrocarbons
(
THC)
concentrations
for
incinerators)

°
Management
practices
(
e.
g.,
siting
restrictions,
design
requirements,
operating
practices)

°
Monitoring
requirements
(
e.
g.,
pollutants
to
be
monitored,
sampling
locations,
frequency,
and
sample
collection
and
analytical
methods)

°
Recordkeeping
requirements
°
Reporting
requirements
(
e.
g.,
contents
of
reports
and
frequency
or
due
dates
for
submission
of
reports)

°
General
requirements
(
e.
g.,
specific
notification
requirements
prior
to
land
application,
submission
of
closure
and
post
closure
plan
for
surface
disposal
sites).

60USEPA
(
1993).
Preparing
Sewage
Sludge
for
Land
Application
or
Surface
Disposal
 
A
Guide
for
Preparers
of
Sewage
Sludge
on
the
Monitoring,
Recordkeeping,
and
Reporting
Requirements
of
the
Federal
Standards
for
the
Use
or
Disposal
of
Sewage
Sludge
in
40
CFR
Part
503.
EPA­
831/
B­
93­
002a.
Office
of
Water.

61USEPA
(
1993).
Domestic
Septage
Regulatory
Guidance
 
A
Guide
to
the
EPA
503
Rule.
EPA­
832/
B­
92­
005.
Office
of
Water.

62USEPA
(
1992).
Control
of
Pathogens
and
Vector
Attraction
in
Sewage
Sludge.
EPA­
625/
R­
92­
013.
Office
of
Research
and
Development.

63USEPA
(
1995).
Part
503
Implementation
Guidance.
EPA
833­
R­
95­
001.
Office
of
Water.

158
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
In
addition
to
any
specific
applicable
40
CFR
Part
503
standards,
three
boilerplate
conditions
must
be
written
in
the
NPDES
permit:
(
1)
language
requiring
the
POTW/
TWTDS
to
comply
with
all
existing
requirements
for
sludge
use
and
disposal,

including
the
40
CFR
Part
503
standards,
(
2)
a
reopener
clause,
which
authorizes
reopening
a
permit
to
include
technical
standards
if
the
technical
standards
are
more
stringent
or
more
comprehensive
than
the
conditions
in
the
permit,
and
(
3)
a
notification
provision
requiring
the
permittee
to
give
notice
to
the
permitting
authority
when
a
significant
change
in
the
sludge
use
or
disposal
practice
occurs
(
or
is
planned).

If
permit
conditions
based
on
existing
regulations
are
insufficient
to
protect
public
health
and
the
environment
from
adverse
effects
that
may
occur
from
toxic
pollutants
in
sewage
sludge,
permit
conditions
should
be
developed
on
a
case­
by­
case
basis
using
BPJ
to
fulfill
the
statutory
requirement.
EPA's
Part
503
Implementation
Guidance
64
contains
information
to
assist
permit
writers
in
developing
pollutant
limits
and
management
practice
requirements
on
a
case­
by­
case
basis
to
protect
public
health
and
the
environment
from
adverse
effects
that
may
occur
from
toxic
pollutants
in
sewage
sludge.

8.3.3
Combined
Sewer
Overflows
(
CSOs)

Combined
sewer
systems
are
designed
to
collect
both
sanitary
and
industrial
wastewater
and
storm
water
runoff.
During
dry
weather,
combined
sewers
carry
sanitary
wastes
and
industrial
discharges
to
a
treatment
plant.
In
periods
of
heavy
rainfall,
however,
the
combined
storm
water
runoff
and
untreated
sanitary
sewage,

including
industrial
wastewater,
can
overflow
and
discharge
this
untreated
wastewater
directly
to
a
water
body.
These
overflows
are
called
combined
sewer
overflows
(
CSOs).

On
April
19,
1994,
EPA
published
a
CSO
Control
Policy
in
the
Federal
Register
(
59
FR
18688)
which
represents
a
comprehensive
national
strategy
to
ensure
that
municipalities,
permitting
authorities,
water
quality
standards
authorities,
and
the
public
engage
in
a
comprehensive
and
coordinated
planning
effort
to
achieve
cost
effective
CSO
controls
that
ultimately
meet
appropriate
health
and
environmental
objectives.

64USEPA
(
1995).
Part
503
Implementation
Guidance.
EPA
833­
R­
95­
001.
Office
of
Water.

NPDES
Permit
Writers'
Manual
­
159
Chapter
8
Special
Conditions
CSOs
are
point
source
discharges
subject
to
both
the
technology­
based
requirements
of
the
CWA
and
to
applicable
State
water
quality
standards.
Under
the
CWA,
CSOs
must
comply
with
the
BAT
for
nonconventional
and
toxic
pollutants
and
BCT
for
conventional
pollutants.
However,
there
are
no
promulgated
BAT/
BCT
effluent
guidelines
and
limitations
for
CSOs.
As
a
result,
permit
writers
must
use
BPJ
in
developing
technology­
based
permit
requirements
for
controlling
CSOs.
In
addition,

permit
conditions
must
achieve
compliance
with
applicable
water
quality
standards.

The
1994
CSO
Control
Policy
contains
the
recommended
approach
for
developing
and
issuing
NPDES
permits
to
control
CSOs.
In
addition,
EPA
has
developed
the
following
guidance
documents
to
help
permit
writers
and
permittees
implement
the
CSO
Control
Policy:

°
Combined
Sewer
Overflows
 
Guidance
for
Long­
Term
Control
Plan.
65
°
Combined
Sewer
Overflows
 
Guidance
for
Nine
Minimum
Controls.
66
°
Combined
Sewer
Overflows
 
Guidance
for
Screening
and
Ranking.
67
°
Combined
Sewer
Overflows
 
Guidance
for
Monitoring
and
Modeling.
68
°
Combined
Sewer
Overflows
 
Guidance
for
Financial
Capability
Assessment
and
Schedule
Development.
69
°
Combined
Sewer
Overflows
 
Guidance
for
Funding
Options.
70
°
Combined
Sewer
Overflows
 
Guidance
for
Permit
Writers.
71
65USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Long­
Term
Control
Plan.
EPA­
832/
B­
95­
002.

66USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Nine
Minimum
Controls.
EPA­
832/
B­
95­
003.

67USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Screening
and
Ranking.
EPA­
832/
B­
95­
004.

68USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Monitoring
and
Modeling.
(
DRAFT).
EPA­
832/
B­
95­
005.

69USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Financial
Capability
Assessment
and
Schedule
Development
(
DRAFT).
EPA­
832/
B­
95­
006.

70USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Funding
Options.
EPA­
832/
B­
95­
007.

71USEPA
(
1995).
Combined
Sewer
Overflows
 
Guidance
for
Permit
Writers.
EPA­
832/
B­
95­
008.

160
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
Combined
Sewer
Overflows
 
Guidance
for
Permit
Writers
contains
guidance,

and
example
permit
language
that
the
permit
writer
can
use.
Because
the
control
of
CSOs
typically
requires
substantial
long­
term
planning,
construction,
financing
and
continuous
reassessment,
the
implementation
of
CSO
controls
will
probably
occur
over
several
permit
cycles.
The
Combined
Sewer
Overflows
 
Guidance
for
Permit
Writers
explains
a
phased
permitting
approach
to
CSOs.
Exhibit
8­
1
depicts
this
phased
permitting
approach
and
the
types
of
permitting
conditions
that
should
be
developed
for
each
phase.
Depending
on
the
particular
permittee's
situation,
a
permit
may
contain
both
Phase
I
and
Phase
II
elements.
The
initial
permit
conditions
for
CSOs,

called
Phase
I
permit
requirements,
should
address:

°
Implementation
of
technology­
based
CSO
controls
as
soon
as
possible
but
no
later
than
January
1,
1997.
The
policy
describes
nine
CSO
control
measures
that
may
be
considered
minimum
BAT/
BCT,
based
on
the
permit
writer's
BPJ.
Exhibit
8­
2
shows
the
nine
minimum
controls
(
NMC).

°
Development
of
a
CSO
Long­
Term
Control
Plan
(
LTCP)
generally
within
2
years
of
permit
issuance.
The
policy
describes
the
minimum
elements
which
the
LTCP
should
address.
Exhibit
8­
3
shows
those
minimum
elements.

The
second
round
of
NPDES
permits
to
control
CSOs,
called
Phase
II,
will
contain
specific
permit
conditions
addressing
continued
implementation
of
the
NMC
and
implementation
of
the
selected
long­
term
CSO
control
measures
identified
in
the
LTCP.
The
permit
writer
will
need
to
review
the
permittee's
LTCP
and
consult
with
other
staff
involved
in
the
CSO
control
process
and
the
permittee
to
determine
the
appropriate
permit
conditions.
Water
quality­
based
controls
will
be
expressed
as
narrative
requirements
and
performance
standards
for
the
combined
sewer
system.

Finally,
post
Phase
II
permit
conditions
would
address
continued
implementation
of
the
NMC,
long­
term
CSO
controls,
and
post­
construction
compliance
monitoring.
There
may
also
be
numeric
water
quality­
based
effluent
limits
when
sufficient
data
exists
to
support
their
development.

NPDES
Permit
Writers'
Manual
­
161
Chapter
8
Special
Conditions
EXHIBIT
8­
1
Categories
of
CSO
Permitting
Conditions
EXHIBIT
8­
1
Categories
of
CSO
Permitting
Conditions
Time
(
yrs)
0
....................
5................
10............>

NPDES
Permit
Phase
I
Phase
II
Post
Phase
II
A.
Technology­
Based
°
NMC,
at
a
minimum
°
NMC,
at
a
minimum
°
NMC,
at
a
minimum
B.
Water
Quality­
Based
°
Narrative
°
Narrative
+

performancebased
standards
°
Narrative
+

performancebased
standards
+

numeric
water
qualitybased
effluent
limits
(
as
appropriate)

C.
Monitoring
°
Characterization,

monitoring,
and
modeling
of
CSS
°
Monitoring
to
evaluate
water
quality
impacts
°
Monitoring
to
determine
effectiveness
of
CSO
controls.
°
Post­
construction
compliance
monitoring
D.
Reporting
°
Documentation
of
NMC
implementation
°
Interim
LTCP
deliverables.
°
Implementation
of
CSO
controls
(
both
NMC
and
long­
term
controls)
°
Report
results
of
postconstruction
compliance
monitoring
E.
Special
Conditions
°
Prohibition
of
dry
weather
overflows
(
DWO)

°
Development
of
LTCP.
°
Prohibition
of
DWO
°
Implementation
of
LTCP
°
Reopener
clause
for
water
quality
standards
violations
°
Sensitive
area
reassessment.
°
Prohibition
of
DWO
°
Reopener
clause
for
water
quality
standards
violations.

162
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
In
developing
permit
requirements
to
meet
technology­
based
requirements
and
EXHIBIT
8­
2
Nine
Minimum
CSO
Controls
1.
Proper
operation
and
regular
maintenance
programs
for
the
sewer
system
and
the
CSOs
2.
Maximum
use
of
the
collection
system
for
storage
3.
Review
and
modification
of
pretreatment
requirements
to
ensure
that
CSO
impacts
are
minimized
4.
Maximization
of
flow
to
the
POTW
for
treatment
5.
Prohibition
of
CSOs
during
dry
weather
6.
Control
of
solid
and
floatable
materials
in
CSOs
7.
Establishment
of
pollution
prevention
programs
8.
Public
notification
to
ensure
that
the
public
receives
adequate
notification
of
CSO
occurrences
and
CSO
impacts
9.
Monitoring
to
effectively
characterize
CSO
impacts
and
the
efficacy
of
CSO
controls.

EXHIBIT
8­
3
Elements
of
the
Long­
Term
CSO
Control
Plan
1.
Characterization,
monitoring,
and
modeling
of
the
combined
sewer
system
2.
Public
participation
3.
Consideration
of
sensitive
areas
4.
Evaluation
of
alternatives
5.
Cost/
performance
considerations
6.
Operational
plan
7.
Maximizing
treatment
at
the
existing
POTW
treatment
plant
8.
Implementation
schedule
9.
Post­
construction
compliance
monitoring
program.

applicable
State
water
quality
standards,
the
permit
writer
in
conjunction
with
staff
involved
in
water
quality
standards
and
the
permittee,
should
identify
the
appropriate
site­
specific
considerations
that
will
determine
the
CSO
conditions
to
be
established
in
the
permit.
EPA
believes
that
the
following
information
will
be
particularly
relevant
in
developing
the
appropriate
conditions:

NPDES
Permit
Writers'
Manual
­
163
Chapter
8
Special
Conditions
°
CSO
Discharge
 
Flow,
frequency,
and
duration
of
the
CSO
discharge
 
Available
effluent
characterization
data
on
the
CSO
discharge
 
Available
information
and
data
on
the
impacts
of
the
CSO
discharge(
s)
(
e.
g.,
305(
b)
reports,
ambient
survey
data,
fish
kills,
304(
l)
lists
of
impaired
waters)
 
Compliance
history
of
the
CSO
owner,
including
performance
and
reliability
of
any
existing
CSO
controls
 
Current
NPDES
permit
and
NPDES
permit
application
 
Facility
planning
information
from
the
permittee
which
addresses
CSOs
°
Technologies
 
Performance
data
(
either
from
the
manufacturer
or
from
other
applications)
for
various
CSO
technologies
that
may
be
employed,
including
equipment
efficiency
and
reliability
 
Cost
information
associated
with
both
the
installation,
operation
and
maintenance
of
CSO
technologies
 
Reference
materials
on
various
types
of
CSO
technologies
(
e.
g.,
Water
Environment
Federation
Manual
of
Practice,
American
Society
of
Chemical
Engineers
publications).

8.3.4
Sanitary
Sewer
Overflows
(
RESERVED)

8.3.5
Municipal
Separate
Storm
Sewer
Systems
(
MS4)

The
November
16,
1990
(
55
FR
47990)
storm
water
application
regulations
established
requirements
for
a
two­
part
permit
application
that
allows
local
governments
to
assist
in
defining
priority
pollutant
sources
within
the
municipality
and
to
develop
and
implement
appropriate
controls
for
such
discharges
to
MS4.
Part
II
of
the
application
required
municipal
applicants
to
propose
municipal
storm
water
management
programs
to
control
pollutants
to
the
"
maximum
extent
practicable"

(
MEP)
and
to
effectively
prohibit
non­
storm
water
discharges
to
the
municipal
system.

Municipal
storm
water
management
programs
are
a
combination
of
source
controls
and
management
practices
that
address
targeted
sources
within
the
boundaries
of
the
municipal
system.
For
example,
a
municipality
that
expects
significant
new
development
may
focus
more
on
proposing
requirements
for
new
development
and
construction.
On
the
other
hand,
a
municipality
that
does
not
expect
significant
new
development
may
focus
more
on
municipal
activities
that
affect
storm
water
quality
164
­
NPDES
Permit
Writers'
Manual
Special
Conditions
Chapter
8
such
as:
maintenance
of
leaking
sanitary
sewers,
road
de­
icing
and
maintenance,

operation
of
municipal
landfills,
flood
control
efforts,
and
control
of
industrial
contributions
of
storm
water.

As
with
any
NPDES
permit,
MS4
permits
must
assure
compliance
with
applicable
technology­
based
requirements
(
in
this
case,
the
MEP)
as
well
as
applicable
water
quality
standards.
However,
unlike
POTWs
where
technology­
based
requirements
are
defined
by
secondary
treatment
standards,
and
most
industrial
sources
that
have
promulgated
ELGs,
there
are
no
promulgated
technology­
based
standards
that
define
MEP.
Therefore,
permit
writers
must
rely
on
application
requirements
specified
in
the
regulations
and
the
applicants
proposed
management
program
when
developing
appropriate
permit
conditions.
EPA
has
developed
the
following
guidance
document
to
assist
permit
writers
as
well
as
permittees
to
implement
the
Municipal
Storm
Water
Program:

°
Guidance
Manual
for
the
Preparation
of
Part
2
of
the
NPDES
Permit
Applications
For
Discharge
From
Municipal
Separate
Storm
Sewer
Systems.
72
72USEPA
(
1992).
Guidance
Manual
for
the
Preparation
of
Part
2
of
the
NPDES
Permit
Application
for
Discharges
from
Municipal
Separate
Storm
Sewer
Systems.
EPA­
833/
B­
92­
002.
Office
of
Water.

NPDES
Permit
Writers'
Manual
­
165
Chapter
12
Permit
Compliance
and
Enforcement
12.1
Overview
Achieving
and
maintaining
a
high
level
of
compliance
with
environmental
laws
and
regulations
are
two
of
the
most
important
goals
of
Federal
and
State
environmental
agencies.
Enforcement
provides
a
powerful
incentive
for
NPDES
permittees
to
comply.
How
an
NPDES
permit
is
written
directly
affects
its
enforceability.
Each
permit
must
be
written
clearly
and
without
ambiguities
so
that
compliance
with
the
permit
can
be
tracked
effectively
and
the
permit
can
be
enforced
in
the
event
that
violations
occur.

The
permit
writer
may
or
may
not
become
actively
involved
with
the
compliance
monitoring
and
enforcement
of
the
terms
and
conditions
of
the
NPDES
permits
that
he
or
she
has
written.
The
extent
of
the
permit
writer's
involvement
will
usually
depend
upon
the
organizational
structure
of
the
regulatory
agency.
Larger,
centrally
organized
agencies
will
typically
have
specialized
personnel
responsible
for
enforcing
the
terms
of
NPDES
permits.
In
other
organizations,
the
individual
who
writes
the
permit
will
also
be
responsible
for
such
enforcement
activities
as
Discharge
Monitoring
Report
(
DMR)
tracking,
facility
inspections,
and
enforcement
recommendations.
In
the
event
NPDES
Permit
Writers'
Manual
­
211
Chapter
12
Permit
Compliance
and
Enforcement
of
a
judicial
enforcement
action,
the
permit
writer
may
be
called
upon
to
testify
regarding
the
specific
requirements
of
the
permit
or
its
basis.

Regardless
of
the
type
of
organizational
structure
within
a
regulatory
agency,

the
permit
writer
should
have
an
appreciation
for
the
various
aspects
of
a
meaningful
NPDES
compliance
enforcement
program.
The
compliance
monitoring
reviews
and
inspections,
and
resulting
data
entered
into
the
Quarterly
Noncompliance
Report
database
which
provide
the
basis
for
evaluating
compliance
are
addressed
in
the
following
section.
The
chapter
concludes
with
a
brief
description
of
the
enforcement
actions
available
to
facilitate
permit
compliance.

12.2
Compliance
Monitoring
Compliance
monitoring
is
a
generic
term
that
includes
all
activities
undertaken
by
Federal
or
State
regulatory
agencies
to
ascertain
a
permittee's
adherence
to
a
NPDES
permit.
Compliance
monitoring
data
collected
as
part
of
the
NPDES
Program
are
used
in
compliance
evaluation
and
in
support
of
enforcement.
The
process
includes
receiving
data,
reviewing
data,
entering
data
into
the
Permit
Compliance
System
(
PCS)
data
base,
identifying
violators,
and
determining
an
appropriate
response.

A
primary
function
of
the
compliance
monitoring
program
is
the
verification
of
compliance
with
permit
conditions,
including
effluent
limitations
and
compliance
schedules.
Compliance
monitoring
may
be
described
as
comprising
two
elements:

°
Compliance
Review
 
The
review
of
all
written
reports
and
other
material
relating
to
the
status
of
a
permittee's
compliance.

°
Compliance
Inspections
 
Field­
related
regulatory
activities,
including
sampling,
conducted
to
determine
compliance.

12.2.1
Compliance
Review
Compliance
and
enforcement
personnel
use
two
primary
sources
of
information
to
carry
out
their
compliance
review
responsibilities:

°
Permit/
Compliance
Files
 
These
files
include
compliance
schedule
reports,
compliance
inspection
reports,
DMRs,
enforcement
actions,
and
212
­
NPDES
Permit
Writers'
Manual
Permit
Compliance
and
Enforcement
Chapter
12
any
other
correspondence
(
e.
g.,
summaries
of
telephone
calls,
copies
of
warning
letters).
Compliance
personnel
periodically
review
this
information
and
use
it
to
determine
if
enforcement
is
necessary
and
what
level
of
enforcement
is
appropriate.

°
PCS
 
PCS
is
a
data
management
system
used
to
compile
all
relevant
facts
about
a
facility's
permit
conditions,
self­
monitoring
data,
the
inspections
performed,
and
any
enforcement
actions
taken.
PCS
is
the
national
data
base
for
the
NPDES
Program.
As
such,
PCS
promotes
national
consistency
and
uniformity
in
permit
and
compliance
evaluations.
To
accomplish
this
goal,
all
required
data
are
entered
into
and
maintained
regularly
in
PCS.

NPDES
permits
must
be
written
so
that
compliance
data
are
capable
of
being
tracked
by
PCS.
There
may
be
situations
where
permit
limits
and
monitoring
conditions
are
not
initially
compatible
with
PCS
entry
and
tracking.
In
these
cases,

States
should
ensure
that
appropriate
steps
are
taken
by
the
permit
writer
to
identify
difficult
permits
to
the
person
responsible
for
entering
PCS
codes
(
either
in
the
State
or
the
Region)
and
to
mutually
resolve
any
coding
issues.
To
assist
PCS
coders
in
accurately
interpreting
and
coding
the
permit
into
PCS
and
to
assist
enforcement
personnel
in
reviewing
permittee
self­
monitoring
data
and
reports
in
a
timely
manner,

permit
writers
should
apply
the
compliance
inspection
procedures
discussed
in
the
next
section
(
Section
12.2.2).

12.2.2
Compliance
Inspections
Compliance
inspections
refer
to
all
field­
related
regulatory
activities
conducted
to
determine
permit
compliance.
Such
field
activities
may
include
evaluation
inspections
(
nonsampling),
sampling
inspections,
other
specialized
inspections,
and
remote
sensing.
Certain
inspections,
such
as
diagnostic
inspections
and
performance
audit
inspections,
aid
the
regulatory
agency
in
evaluating
the
facility's
problems
in
addition
to
providing
information
to
support
enforcement
action.
Biomonitoring
inspections
are
specifically
targeted
at
facilities
with
effluent
suspected
or
identified
as
causing
toxicity
problems
that
threaten
the
ecological
balance
of
the
receiving
waters.

NPDES
Permit
Writers'
Manual
­
213
Chapter
12
Permit
Compliance
and
Enforcement
Compliance
inspections
are
undertaken
for
one
or
more
of
the
following
purposes:

°
To
establish
a
regulatory
presence
to
defer
violations
°
To
ensure
that
permit
requirements
are
being
met
or
to
determine
if
permit
conditions
are
adequate
°
To
check
the
completeness
and
accuracy
of
a
permittee's
performance
and
compliance
records
°
To
assess
the
adequacy
of
the
permittee's
self­
monitoring
and
reporting
program
°
To
determine
the
progress
or
completion
of
corrective
action
°
To
obtain
independent
compliance
data
on
a
facility's
discharge
°
To
evaluate
the
permittee's
operation
and
maintenance
activities
°
To
observe
the
status
of
construction
required
by
the
permit.

12.3
Quarterly
Noncompliance
Reports
EPA
Regional
Offices
and
States
that
have
been
approved
to
administer
the
NPDES
Program
are
required
by
regulation
to
report
quarterly
on
major
facilities
that
are
not
in
compliance
with
the
terms
and
conditions
of
their
permit
(
i.
e.,
effluent
limitations
meet
the
criteria
for
reportable
noncompliance
[
RNC],
schedules,
and
reporting
requirements).

The
regulations
in
40
CFR
123.45
established
requirements
for
listing
facility
violations
and
resulting
regulatory
enforcement
action
or
quarterly
noncompliance
reports
(
QNCRs).
This
regulation
established
reporting
requirements
for
violations
that
meet
specific,
quantifiable
reporting
criteria,
as
well
as
for
violations
that
are
more
difficult
to
quantify
but
are
of
sufficient
concern
to
be
considered
reportable.
The
regulation
also
specifies
the
format
that
the
reports
must
follow
and
the
schedule
for
their
submission.

Only
major
facilities
that
meet
RNC
criteria
must
be
reported
on
the
QNCR.

RNC
consists
of
five
general
types
of
violations:

°
Violation
of
Monthly
Average
Effluent
Limits
 
Data
that
exceeds
or
equals
the
limit
times
the
Technical
Review
Criteria
(
TRC)
for
2
months
during
a
6­
month
period,
where
the
TRC
is
1.4
for
Group
I
pollutants
and
214
­
NPDES
Permit
Writers'
Manual
Permit
Compliance
and
Enforcement
Chapter
12
1.2
for
Group
II
pollutants
(
Appendix
A
to
40
CFR
Part
123
contains
a
list
of
Group
I
and
II
pollutants);
and
data
that
exceeds
the
limit
for
4
months
during
a
6­
month
period.

°
Interim
Effluent
Limits
Set
Forth
in
a
Formal
Enforcement
Action
 
Any
violation
of
any
magnitude.

°
Schedule
 
Missing
a
compliance
schedule
milestone
date
by
90
days.

°
Reporting
 
Missing
a
report
due
date
by
30
days.

°
Single
Event
 
A
violation
of
any
magnitude
considered
to
have
an
adverse
effect
on
water
quality
or
public
health
(
e.
g.,
unauthorized
bypass,
unpermitted
discharge,
frequent
discharges
of
a
variety
of
pollutants).

A
subset
of
instances
of
RNC
that
appear
on
the
QNCR
may
be
noted
as
significant
noncompliance
(
SNC).
This
distinction
is
used
solely
for
management
accountability
purposes
as
a
means
of
tracking
trends
in
compliance
and
evaluating
relative
timeliness
of
appropriate
enforcement
response
toward
priority
violations.
The
definition
of
SNC
is
not
regulatory
and
may
change
as
the
NPDES
Program
changes
to
encompass
new
initiatives.
Generally,
the
designation
of
SNC
indicates
a
violation
is
of
sufficient
magnitude
and/
or
duration
to
be
considered
among
the
Agency's
priorities
for
regulatory
review
and/
or
response.
The
categories
of
SNC
are:

°
Violation
of
enforcement
action
requirements
(
i.
e.,
administrative
effluent
limits,
key
compliance
schedule
milestones,
and
key
reports)

°
Violation
of
permit
effluent
limits
°
Violation
of
key
compliance
schedule
milestones
contained
in
a
permit
°
Violation
of
key
reporting
requirements
in
a
permit
°
Any
unauthorized
discharge
or
bypass
considered
significant
by
the
NPDES
Program
director
°
Violations
associated
with
water
quality
or
health
impacts.

The
Regions
and
NPDES
States
are
expected
to
prioritize
rapid
enforcement
action
against
all
SNC
violations
by
the
time
they
appear
on
the
first
QNCR.
Prior
to
a
permittee
appearing
on
the
subsequent
QNCR
for
the
same
instance
of
SNC,
the
permittee
should
either
be
in
compliance
or
the
administering
agency
should
have
initiated
an
appropriate
formal
enforcement
action
to
achieve
final
compliance.
If
the
facility
is
still
considered
SNC
after
two
quarters
and
no
formal
enforcement
action
has
been
taken,
the
facility
is
placed
on
the
Exceptions
List.
Although
there
are
some
legitimate
justifications
for
facilities
appearing
on
the
Exception
List,
the
Exceptions
NPDES
Permit
Writers'
Manual
­
215
Chapter
12
Permit
Compliance
and
Enforcement
List
generally
indicates
facilities
for
which
the
administering
agency
failed
to
handle
enforcement
in
a
timely
and
appropriate
manner.

12.4
Enforcement
Regulatory
Update
In
September
1995,
EPA
revised
the
definition
of
SNC
to
include
violations
of
non­
monthly
average
permit
limits
by
major
facilities.
A
large
percentage
of
NPDES
majors
are
lacking
the
required
monthly
average
limits
in
their
permit
thus
escaping
detection
as
SNC
and
scrutiny
for
formal
enforcement
action.
The
new
definition
was
effective
on
October
1,
1996
and
is
expected
to
result
in
better
targeting
of
limited
enforcement
resources
to
violations
posing
the
greatest
risk
to
the
environment
and
public
health.

Specific
enforcement
actions
are
focused
on
a
small
subset
of
the
total
number
of
violators
 
violators
at
sites
where
frequent
or
serious
violations
have
occurred.

However,
these
actions
have
the
effect
of
fostering
compliance
by
an
entire
industry
of
facilities
across
the
nation.
By
choosing
the
appropriate
enforcement
response
to
violations,
EPA
tries
to
achieve
several
goals:

°
Correction
of
the
violation
as
soon
as
possible
°
Deterrence
of
future
violations
by
the
same
permittee
or
other
permittees
°
Equal
treatment
of
the
regulated
community
through
use
of
a
uniform
approach
to
selecting
enforcement
responses
(
i.
e.,
similar
violations
are
treated
similarly)

°
Punishment
of
serious
violations
°
Effective
use
of
enforcement
resources
by
achieving
protection
of
human
health
and
the
environment
with
the
least
amount
of
staff
time
and
funds.

Once
a
facility
has
been
identified
as
having
apparent
permit
violations,
the
EPA
or
the
NPDES
State
or
Tribal
organization
will
review
the
facility's
compliance
history.
Such
a
review
includes
an
assessment
of
the
magnitude,
frequency,
and
duration
of
violations.
Significant
permit
violations
are
identified
and
a
determination
of
the
appropriate
enforcement
response
is
made.

Section
309
of
the
Act
authorizes
the
Agency
to
bring
civil
or
criminal
action
against
facilities
which
violate
their
NPDES
permit
conditions.
EPA
Regions
and
authorized
States
have
specific
procedures
for
reviewing
self­
monitoring
and
inspection
data
and
for
deciding
what
type
of
enforcement
action
is
warranted.
EPA
216
­
NPDES
Permit
Writers'
Manual
Permit
Compliance
and
Enforcement
Chapter
12
recommends
an
escalating
response
to
continuing
noncompliance.
Typical
types
of
enforcement
actions
include:

°
Inspection
debriefing,
calling
attention
to
deficiencies
°
Telephone
call
°
Letter
of
violation
°
Notice
of
violation
°
Administrative
order
°
Administrative
fine
of
up
to
$
125,000
per
proceeding
°
Civil
lawsuit
°
Criminal
prosecution.

Considerations
when
making
determinations
on
the
level
of
the
enforcement
response
include
(
1)
the
severity
of
the
permit
violation,
(
2)
the
degree
of
economic
benefit
obtained
through
the
violation,
(
3)
previous
enforcement
actions
taken
against
the
violator,
and
(
4)
the
deterrent
effect
of
the
response
on
similarly
situated
permittees.
Equally
important
are
considerations
of
fairness
and
equity,
national
consistency,
and
the
integrity
of
the
NPDES
Program.

12.5
Public
Participation
Citizens
can
participate
in
the
enforcement
process
in
a
number
of
ways.

Under
the
Freedom
of
Information
Act,
citizens
have
the
right
to
request
certain
facility­
specific
compliance
information
from
EPA's
PCS
database.
Interested
citizens
can
intervene
in
any
Federal
civil
action
to
enjoin
any
threatened
or
continuing
violation
of
any
program
requirement
or
permit
conditions,
and
to
recover
civil
penalties
in
court.
Citizens
also
have
the
opportunity
to
review
and
comment
on
any
proposed
consent
decree
to
resolve
a
State
or
Federal
civil
judicial
enforcement
action.

Section
505
of
the
Clean
Water
Act
allows
any
citizen
to
commence
a
civil
judicial
enforcement
action
on
his
own
behalf
against:
(
1)
any
person
(
including
the
United
States
or
any
government
agency)
who
is
alleged
to
be
in
violation
of
an
effluent
standard
or
limitation
or
an
enforcement
order
issued
by
EPA
or
a
State,
or
(
2)
against
EPA
or
the
State
where
the
regulatory
authority
is
alleged
to
have
failed
to
take
appropriate
action.
Citizens
may
not
commence
suit
if
EPA
or
the
State
is
NPDES
Permit
Writers'
Manual
­
217
Chapter
12
Permit
Compliance
and
Enforcement
diligently
prosecuting
a
civil
or
criminal
action.
Citizens
must
also
give
EPA,
the
State,

and
the
alleged
violator
sixty
days'
notice
of
the
alleged
violation
prior
to
commencing
a
citizen
suit.

12.6
Compliance
Assistance
and
Voluntary
Compliance
Policies
On
June
8,
1994,
EPA
established
a
new
Office
of
Enforcement
and
Compliance
Assurance
(
OECA),
consolidating
a
number
of
functions
formerly
shared
among
different
programs
at
EPA.
One
of
several
new
offices
in
OECA
is
the
Office
of
Compliance
(
OC).
The
overriding
mission
of
the
Office
of
Compliance
is
to
improve
compliance
with
environmental
laws.
To
do
this,
OC
sets
national
compliance
assurance
and
enforcement
priorities
through
strategic
planning
and
targeting;
collects
and
integrates
compliance
data;
develops
effective
compliance
monitoring
programs
to
support
inspections
and
self­
reporting;
builds
the
capacity
for
more
effective
compliance
assistance
to
the
regulated
community;
works
with
Regions,
States,

municipalities,
citizens
groups
and
industry,
and
supports
enforcement
activity.
Three
of
the
divisions
in
OC
are
organized
by
economic
sector
(
SIC
Code).

As
part
of
President
Clinton's
1995
regulatory
form
initiative,
EPA's
Office
of
Enforcement
and
Compliance
Assurance
issued
three
policies
to
provide
incentives
for
voluntary
compliance.
The
first
is
"
Incentives
for
Self­
Policing:
Disclosure,
Correction
and
Prevention
of
Violations"
(
hereafter
referred
to
as
the
"
self­
audit
policy"),
which
was
issued
on
December
22,
1995.
This
policy
officers
incentives
in
the
form
of
elimination
of
gravity­
based
penalties
to
companies
that
find
violations
through
an
environmental
audit
or
efforts
that
reflect
due
diligence,
and
promptly
disclose
and
correct
those
violations.
It
also
offers
a
75%
reduction
in
gravity­
based
penalties
for
violations
that
are
voluntarily
discovered
and
disclosed
even
if
not
found
through
an
audit
or
the
exercise
of
due
diligence.
The
self­
audit
policy
contains
important
safeguards
to
protect
public
health
such
as:
excluding
violations
which
may
present
an
imminent
and
substantial
endangerment
or
have
resulted
in
serious
actual
harm;

retaining
the
right
to
recover
any
significant
economic
benefit
gained
by
the
violator;

requiring
the
company
to
remedy
any
environmental
harm;
and,
excluding
repeat
violations.

The
second
policy
is
EPA's
"
Policy
on
Compliance
Incentives
for
Small
Businesses"
(
hereafter
referred
to
as
the
"
small
business
policy")
which
became
218
­
NPDES
Permit
Writers'
Manual
Permit
Compliance
and
Enforcement
Chapter
12
effective
on
June
10,
1996.
The
purpose
of
this
policy
is
to
promote
compliance
among
small
businesses
by
providing
them
with
special
incentives
to
participate
in
compliance
assistance
programs
or
to
conduct
environmental
audits,
and
then
to
promptly
correct
violations.
Under
the
small
business
policy,
a
"
small
business"
is
a
person,
corporation,
partnership,
or
other
entity
who
employs
100
or
fewer
individuals
across
all
its
facilities
and
operations.
EPA
will
eliminate
the
entire
civil
penalty
if
a
small
business
satisfies
all
four
of
the
following
criteria:
(
1)
the
business
has
made
a
good
faith
effort
to
comply
as
demonstrated
by
either
receiving
on­
site
governmental
compliance
assistance
or
conducting
a
voluntary
environmental
audit
and
promptly
disclosing
in
writing
all
violations
discovered
as
part
of
the
audit;
(
2)
in
past
three
years,
the
business
was
not
subject
to
an
action
for
the
current
violation
and
in
the
past
five
years
the
small
business
has
not
been
subject
to
two
or
more
enforcement
actions
for
environmental
violations;
(
3)
the
business
corrects
the
violation
and
remedies
any
harm
associated
with
the
violation
within
six
months
of
discovery;
and
(
4)
the
violation
has
not
caused
or
does
not
pose
actual
serious
harm
and
has
not
involved
criminal
conduct.

If
the
small
business
meets
all
of
the
above
criteria
except
that
it
needs
a
longer
corrections
period
or
if
it
has
obtained
a
significant
economic
benefit
from
the
violations,
EPA
will
waive
up
to
100%
of
the
gravity
component
of
the
penalty
but
may
seek
the
full
amount
of
any
economic
benefit
associated
with
the
violations.

The
third
new
policy
is
the
"
Policy
on
Flexible
State
Enforcement
Responses
to
Small
Community
Violations,"
which
was
issued
on
November
22,
1995
(
hereinafter
referred
to
as
the
"
small
community
policy").
The
small
community
policy
assures
States
that
they
have,
within
appropriate
limits,
the
flexibility
to
design
and
use
multimedia
compliance
assistance
and
compliance
prioritization
measures
as
alternatives
to
traditional
enforcement
responses
when
addressing
a
small
community's
environmental
violations.
Under
the
small
community
policy,
State
small
community
environmental
compliance
assistance
programs
provide
(
1)
an
adequate
process
to
return
a
small
community
to
environmental
compliance;
and
(
2)
an
opportunity
to
correct
violations.
States
electing
to
provide
small
community
environmental
compliance
assistance
should
establish
and
follow
an
adequate
process
for
determining
which
communities
can
participate,
assessing
a
community's
good
faith
and
environmental
compliance
status,
determining
a
community's
administrative,

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Manual
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219
Chapter
12
Permit
Compliance
and
Enforcement
technical,
and
financial
capacity
to
comply,
weighting
the
comparative
risks
associated
with
competing
environmental
mandates,
and
entering
into
an
enforceable
agreement
establishing
a
risk­
prioritized
schedule
that
requires
compliance
with
all
environmental
mandates
as
quickly
as
is
reasonable.

A
State
can
waive
part
or
all
of
the
noncompliance
penalty
if
the
community
is
working
diligently
and
in
good
faith
to
achieve
compliance.
The
small
community
policy
does
not
apply
to
criminal
violations.
EPA
also
reserves
the
right
to
take
immediate
action
where
the
community's
actions
create
an
imminent
and
substantial
endangerment
to
public
health
and
the
environment.

220
­
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Manual
