EPA
United
States
Environmental
Protection
Agency
Office
of
Water
EPA­
823­
B94­
005a
(
4305)
August
1994
Water
Quality
Standards
Handbook:

Second
Edition
Contains
Update
#
1
August
1994
"
.
.
.
to
restore
and
maintain
the
chemical,
physical,
and
biological
integrity
of
the
Nation's
waters."

Section
101(
a)
of
the
Clean
Water
Act
WATER
QUALITY
STANDARDS
HANDBOOK
SECOND
EDITION
Water
Quality
Standards
Branch
Office
of
Science
and
Technology
U.
S.
Environmental
Protection
Agency
Washington,
DC
20460
September
1993
Contains
update
#
1
August
1994
READER
RESPONSE
CARD
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THIS
RESPONSE
CARD
FOR
EPA
DOCUMENT
NUMBER:
EPA­
823­
B­
94­
005
U.
S.
Environmental
Protection
Agency
Water
Resource
Center
(
RC­
4100)
401
M
Street,
SW.
Washington,
DC
20460
Table
of
Contents
FOREWORD
Dear
Colleague:

The
following
document
entitled
Water
Quality
Standards
Handbook
­
Second
Edition
provides
guidance
issued
in
support
of
the
Water
Quality
Standards
Regulation
(
40
CFR
131,
as
amended).
This
Handbook
includes
the
operative
provisions
of
the
first
volume
of
the
Handbook
issued
in
1983
and
incorporates
subsequent
guidance
issued
since
1983.
The
1993
Handbook
contains
only
final
guidance
previously
issued
by
EPA
­
it
contains
no
new
guidance.

Since
the
1983
Handbook
has
not
been
updated
in
ten
years,
we
hope
that
this
edition
will
prove
valuable
by
pulling
together
current
program
guidance
and
providing
a
coherent
document
as
a
foundation
for
State
and
Tribal
water
quality
standards
programs.
The
Handbook
also
presents
some
of
the
evolving
program
concepts
designed
to
reduce
human
and
ecological
risks,
such
as
endangered
species
protection;
criteria
to
protect
wildlife.
wetlands.
and
sediment
quality;
biological
criteria
to
better
define
desired
biological
communities
in
aquatic
ecosystems;
and
nutrient
criteria.

This
Handbook
is
intended
to
serve
as
a
"
living
document,"
subject
to
future
revisions
as
the
water
quality
standards
program
moves
forward,
and
to
reflect
the
needs
and
experiences
of
EPA
and
the
States.
To
this
end,
the
Handbook
is
published
in
a
loose
leaf
format
designed
to
be
placed
in
three
ring
binders.
This
copy
of
the
Handbook
includes
updated
material
for
1994
(
see
Appendix
X),
and
EPA
anticipates
publishing
additional
changes
periodically
and
providing
them
to
Handbook
recipients.
To
ensure
that
you
will
receive
these
updates,
please
copy
the
reader
response
card
in
Appendix
W
and
mail
it
to
the
address
on
the
reverse.

The
handbook
also
contains
a
listing,
by
title
and
date,
of
the
guidance
issued
since
the
Handbook
was
first
published
in
1983
that
is
incorporated
in
the
Second
Edition.
Copies
of
these
documents
are
available
upon
request.

The
Water
Quality
Standards
Handbook
­
Second
Edition
provides
guidance
on
the
national
water
quality
standards
program.
EPA
regional
offices
and
States
may
have
additional
guidance
that
provides
more
detail
on
selected
topics
of
regional
interest.
For
information
on
regional
or
State
guidance,
contact
the
appropriate
regional
water
quality
standards
coordinator
listed
in
Appendix
U.

EPA
invites
participation
from
interested
parties
in
the
water
quality
standards
program,
and
appreciates
questions
on
this
guidance
as
well
as
suggestions
and
comments
for
improvement.
Questions
or
comments
may
be
directed
to
the
EPA
regional
water
quality
standards
coordinators
or
to:

David
Sabock,
Chief
U.
S.
Environmental
Protection
Agency
Water
Quality
Standards
Branch
(
4305)
401
M
Street,
S.
W.
Washington,
D.
C.
20460
Telephone
(
202)
475­
7315
Betsy
Southerland,
Acting
Director
Standards
and
Applied
Science
Division
(
8/
15/
94)
III
Water
Quality
Standards
Handbook
­
Second
Edition
Note
to
the
Reader
The
Water
Quality
Standards
Handbook,
first
issued
in
1983,
is
a
compilation
of
EPA's
guidance
on
the
water
quality
standards
program
and
provides
direction
for
States
in
reviewing,
revising
and
implementing
water
quality
standards.
The
Water
Quality
Standards
Handbook
­
Second
Edition
retains
all
the
guidance
in
the
1983
Handbook
unless
such
guidance
was
specifically
revised
in
subsequent
years.
An
annotated
list
of
the
major
guidance
and
policy
documents
on
the
water
quality
standards
program
issued
since
1983
is
included
in
the
Introduction
and
material
added
to
the
Second
Edition
by
periodic
updates
since
1993
is
summarized
in
Appendix
X.
Material
in
the
Handbook
contains
only
guidance
previously
issued
by
EPA;
it
contains
no
new
guidance.

The
guidance
contained
in
each
of
the
documents
listed
in
the
Introduction
is
either:

1)
incorporated
in
its
entirety,
or
summarized,
in
the
text
of
the
appropriate
section
of
this
Handbook,
or
2)
attached
as
an
appendix
(
see
Table
of
Contents).
If
there
is
uncertainty
or
perceived
inconsistency
on
any
of
the
guidance
incorporated
into
this
Handbook,
the
reader
is
directed
to
review
the
original
guidance
documents
or
call
the
Water
Quality
Standards
Branch
at
(
202)
260­
1315.
Copies
of
all
original
guidance
documents
not
attached
as
appendices
may
be
obtained
from
the
source
listed
for
each
document
in
the
Reference
section
of
this
Handbook.

Limited
free
copies
of
this
Handbook
may
be
obtained
from:

Office
of
Water
Resource
Center,
RC­
4100
U.
S.
Environmental
Protection
Agency
401
M
Street,
S.
W.
Washington,
DC
20460
Telephone:
(
202)
260­
7786
(
voice
mail
publication
request
line)

Copies
may
also
be
obtained
from:

Education
Resource
Information
Center/
Clearinghouse
for
Science,
Mathematics
and
Environmental
Education
(
ERIC)
1929
Kenny
Road
Columbus,
OH
43210­
1080
(
Telephone:
614­
292­
6717)
(
VISA,
Mastercard
and
purchase
order
numbers
from
schools
and
businesses
accepted)

U.
S.
Department
of
Commerce
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Technical
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NTIS)
5285
Port
Royal
Road
Springfield,
VA
22161
(
Telephone:
1­
800­
553­
6847)
(
American
Express,
VISA
and
Mastercard
accepted)

Robert
S.
Shippen
Editor
iv
(
8115194)
Table
of
Contents
TABLE
OF
CONTENTS
Foreword
.
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iii
Note
to
the
Reader
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iv
Table
of
Contents
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v
Glossary
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GLOSS­
1
Introduction
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INT­
1
History
of
the
Water
Quality
Standards
Program
.......................
INT­
1
Handbook
Changes
Since
1983
.................................
INT­
5
Overview
of
the
Water
Quality
Standards
Program
.....................
INT­
8
The
Role
of
WQS
in
the
Water
Quality
Management
Program
..............
INT­
13
Future
Program
Directions
...................................
INT­
14
Chapter
1
­
General
Provisions
(
40
CFR
131
­
Subpart
A)

1.1
Scope­
40
CFR
131.1
....................................
1­
1
1.2
Purpose
­
40
CFR
131.2
...................................
1­
1
1.3
Definitions
­
40
CFR
131.3
.................................
1­
1
1.4
State
Authority
­
40
CFR
131.4
..............................
1­
2
1.5
EPA
Authority
­
40
CFR
131.5.
..............................
1­
3
1.6
Requirements
for
Water
Quality
Standards
Submission
­
40
CFR
131.6
......
1­
4
1.7
Dispute
ResoIution
Mechanism
­
40
CFR
131.7
.....................
1­
4
1.8
Requirements
for
Indian
Tribes
To
Qualify
for
the
WQS
Program
­
40
CFR
131.8
.
.
...........................................
1­
9
1.9
Adoption
of
Standards
for
Indian
Reservation
Waters
................
1­
18
Endnotes
................................................
1­
21
Chapter
2
­
Designation
of
Uses
(
40
CFR
131.10)

2.1
Use
Classification
­
40
CFR
131.10(
a)
..........................
2­
1
2.2
Consider
Downstream
Uses
­
40
CFR
131.10(
b)
....................
2­
4
2.3
Use
Subcategories
­
40
CFR
131.10(
c)
..........................
2­
5
2.4
Attainability
of
Uses
.
40
CFR
131.10(
d)
.........................
2­
5
2.5
Public
Hearing
for
Changing
Uses
­
40
CFR
131.10(
e)
................
2­
6
2.6
Seasonal
Uses
­
40
CFR
131.10(
f)
.............................
2­
6
2.7
Removal
of
Designated
Uses
­
40
CFR
131.10(
g)
and
(
h)
..............
2­
6
2.8
Revising
Uses
to
Reflect
Actual
Attainment
­
40
CFR
131.10(
i)
...........
2­
8
2.9
Use
Attainability
Analyses
­
40
CFR
131.10(
j)
and
(
k)
................
2­
9
(
8/
15/
94)
v
Chapter
3
­
Water
Quality
Criteria
(
40
CFR
131.11)

3.1
EPA
Section
304(
a)
Guidance
.....................
32
Relationship
of
Section
304(
a)
Criteria
to
State
Designated
Uses
.........

3.3
State
Criteria
Requirements
......................
3.4
Criteria
for
Toxicants
..........................

3.5
Forms
of
Criteria
............................

3.6
Policy
on
Aquatic
Life
Metals
Criteria
...............

3.7
Site­
Specific
Aquatic
Life
Criteria
..................
Endnotes
......................................

Chapter
4
­
Antidegradation
(
40
CFR
131.12)
3­
1
3­
10
3­
12
3­
13
3­
23
3­
34
3­
38
3­
45
4.7
4.8
History
of
Antidegradation
.
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4­
1
Summary
of
the
Antidegradation
Policy
.
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.
4­
1
State
Antidegradation
Requirements
.
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4­
2
Protection
of
Existing
Uses
­
40
CFR
131.12(
a)(
1)
.
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4­
3
Protection
of
Water
Quality
in
High­
Quality
Waters
­
40
CFR
131.12(
a)(
2)
.
.
.
.
4­
6
Applicability
of
Water
Quality
Standards
to
Nonpoint
Sources
Versus
Enforceability
of
Controls
.
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4­
9
Outstanding
National
Resource:
Waters
(
ONRW)
­
40
CFR
131.12(
a)(
3)
.
.
.
.
4­
10
Antidegradation
Application
and
Implementation
.
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.
4­
10
Chapter
5
­
General
Policies
(
40
CFR
131.13)

5.1
Mixing
Zones
.
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5.2
Critical
Low­
Flows
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5.3
Variances
From
Water
Quality
Standards
.
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.
.

Chapter
6
­
Procedures
for
Review
and
Revision
of
Water
Quality
Standards
(
40
CFR
131
Subpart
C)

6.1
State
Review
and
Revision
............................
6.2
EPA
Review
and
Approval
...........................
6.3
EPA
Promulgation
...............................

Chapter
7
­
The
Water
Quality­
based
Approach
to
Pollution
Control
7.1
Determine
Protection
Level
........................
7.2
Conduct
Water
Quality
Assessment
...................
7.3
Establish
Priorities
.............................
7.4
Evaluate
Water
Quality
Standards
for
Targeted
Waters
.............

7.5
Define
and
Allocate
Control
Responsibilities
..............

7.6
Establish
Source
Controls
........................
7.7
Monitor
and
Enforce
Compliance
...................
7.8
Measure
Progress
................................
5­
1
5­
9
5­
11
6­
1
6­
8
6­
13
7­
2
7­
3
7­
5
7­
6
7­
7
7­
8
7­
12
7­
13
References
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
REF­
1
vi
(
8/
15/
94)
Table
of
Contents
Appendices:

A­
Water
Quality
Standards
Regulation
­
40
CFR
131.

B­
Chronological
Summary
of
Federal
Water
Quality
Standards
Promulgation
Actions.

C­
Biological
Criteria:
National
Program
Guidance
for
Surface
Waters,
April
1990.

D­
National
Guidance:
Water
Quality
Standards
for
Wetlands,
July
1990.

E­
An
Approach
for
Evaluating
Numeric
Water
Quality
Criteria
for
Wetlands
Protection,
July
1991.

F­
Coordination
Between
the
Environmental
Protection
Agency,
Fish
and
Wildlife
Service
and
National
Marine
Fisheries
Service
Regarding
Development
of
Water
Quality
Criteria
and
Water
Quality
Standards
Under
the
Clean
Water
Act,
July
1992.

G
­
Questions
and
Answers
on:
Antidegradation,
August
1985.

H­
Derivation
of
the
1985
Aquatic
Life
Criteria.

I­
List
of
EPA
Water
Quality
Criteria
Documents.

J­
Attachments
to
Office
of
Water
Policy
and
Technical
Guidance
on
Interpretation
and
Implementation
of
Aquatic
Life
Metals
Criteria,
October
1993.

K­
Procedures
for
the
Initiation
of
Narrative,
Biological
Criteria,
October
1992.

L­
Interim
Guidance
on
Determination
and
Use
of
Water­
Effect
Ratios
for
Metals,
February
1994.

M­
Reserved.

N­
IRIS
[
Integrated
Risk
Information
System/
Background
Paper.

O­
Reserved.

P­
List
of
126
Section
307(
a)
Priority
Toxic
Pollutants.

Q­
Wetlands
and
401
Certification:
Opportunities
and
Guidelines
for
States
and
Eligible
Indian
Tribes
­
April
1989.

R­
Policy
on
the
Use
of
Biological
Assessments
and
Criteria
in
the
Water
Quality
Program,
May
1991.

S­
Reserved.

T­
Use
Attainability
Analysis
Case
Studies.

(
8/
15/
94)
vii
Water
Quality
Standards
Handbook
­
Second
Edition
U­
List
of
EPA
Regional
Water
Quality
Standards
Coordinators.

V­
Water
Quality
Standards
Program
Document
Request
Forms.

W­
Update
Request
Form
for
Wafer
Quality
Standards
Handbook
­
Second
Edition.

X­
Summary
of
Updates
viii
(
8/
15/
94)
GLOSSARY
WATER
QUALITY
STANDARDS
HANDBOOK
SECOND
EDITION
Glossary
GLOSSARY
The
"
Act"
refers
to
the
Clean
Water
Act
(
Public
Law
92­
500,
as
amended
(
33
USC
1251,
et.
seq.
)
(
40
CFR
131.3.)

"
Acute"
refers
to
a
stimulus
severe
enough
to
rapidly
induce
an
effect;
in
aquatic
toxicity
tests,
an
effect
observed
in
96­
hours
or
less
is
typically
considered
acute.
When
referring
to
aquatic
toxicology
or
human
health,
an
acute
affect
is
not
always
measured
in
terms
of
lethality
(
USEPA,
1991a.)

"
Acute­
chronic
ratio"
(
ACR)
is
the
ratio
of
the
acute
toxicity
of
an
effluent
or
a
toxic­
ant
to
its
chronic
toxicity.
It
is
used
as
a
factor
for
estimating
chronic
toxicity
on
the
basis
of
acute
toxicity
data,
or
for
estimating
acute
toxicity
on
the
basis
of
chronic
toxicity
data
(
USEPA,
1991a.)

"
Acutely
toxic
conditions"
are
those
acutely
toxic
to
aquatic
organisms
following
their
short­
term
exposure
within
an
affected
area
(
USEPA,
1991a.)

"
Additivity"
is
the
characteristic
property
of
a
mixture
of
toxicants
that
exhibits
a
total
toxic
effect
equal
to
the
arithmetic
sum
of
the
effects
of
the
individual
toxicants
(
USEPA,
1991a.)

"
Ambient
toxicity"
is
measured
by
a
toxicity
test
on
a
sample
collected
from
a
water
body
(
USEPA,
1991a.)

"
Antagonism"
is
the
characteristic
property
of
a
mixture
of
toxicants
that
exhibits
a
less­
than­
additive
total
toxic
effect
(
USEPA,
1991a.)

"
Aquatic
community"
is
an
association
of
interacting
populations
of
aquatic
organisms
in
a
given
water
body
or
habitat
(
USEPA,
1990;
USEPA,
1991a.)

"
Averaging
period"
is
the
period
of
time
over
which
the
receiving
water
concentration
is
averaged
for
comparison
with
criteria
concentrations.
This
specification
limits
the
duration
of
concentrations
above
the
criteria
(
USEPA,
1991a.)

"
Bioaccumulation"
is
the
process
by
which
a
compound
is
taken
up
by
an
aquatic
organism,
both
from
water
and
through
food
(
USEPA,
1991a.)

"
Bioaccumulation
factor"
(
BAF)
is
the
ratio
of
a
substance's
concentration
in
tissue
versus
its
concentration
in
ambient
water,
in
situations
where
the
organism
and
the
food
chain
are
exposed
(
USEPA,
1991a.)

"
Bioassay"
is
a
test
used
to
evaluate
the
relative
potency
of
a
chemical
or
a
mixture
of
chemicals
by
comparing
its
effect
on
a
living
organism
with
the
effect
of
a
standard
preparation
on
the
same
type
of
organism.
Bioassays
are
frequently
used
in
the
pharmaceutical
industry
to
evaluate
the
potency
of
vitamins
and
drugs
(
USEPA,
1991a.)

(
9/
15/
93)
GLOSS­
1
Water
Quality
Standards
Handbook
­
Second
Edition
"
Bioavailability"
is
a
measure
of
the
physicochemical
access
that
a
toxicant
has
to
the
biological
processes
of
an
organism.
The
less
the
bioavailability
of
a
toxicant,
the
less
its
toxic
effect
on
an
organism
(
USEPA,
1991a.)

"
Bioconcentration"
is
the
process
by
which
a
compound
is
absorbed
from
water
through
gills
or
epithelial
tissues
and
is
concentrated
in
the
body
(
USEPA,
1991a.)

"
Bioconcentration
factor"
(
BCF)
is
the
ratio
of
a
substance's
concentration
in
tissue
versus
its
concentration
in
water,
in
situations
where
the
food
chain
is
not
exposed
or
contaminated.
For
non­
metabolized
substances,
it
represents
equilibrium
partitioning
between
water
and
organisms
(
USEPA,
1991a.)

"
Biological
criteria"
are
narrative
expressions
or
numeric
values
of
the
biological
characteristics
of
aquatic
communities
based
on
appropriate
reference
conditions.
As
such,
biological
criteria
Serve
as
an
index
of
aquatic
community
health.
It
is
also
known
as
biocriteria
(
USEPA,
1991a.)

"
Biological
integrity"
is
the
condition
of
the
aquatic
community
inhabiting
unimpaired
water
bodies
of
a
specified
habitat
as
measured
by
community
structure
and
function
(
USEPA,
1991a.)

"
Biological
monitoring"
describes
the
use
of
living
organisms
in
water
quality
surveillance
to
indicate
compliance
with
water
quality
standards
or
effluent
limits
and
to
document
water
quality
trends.
Methods
of
biological
monitoring
may
include,
but
are
not
limited
to,
toxicity
testing
(
such
as
ambient
toxicity
testing
or
whole­
effluent
toxicity
testing)
and
biological
surveys.
It
is
also
known
as
biomonitoring
(
USEPA,
1991a.)

"
Biological
survey
or
biosurvey"
is
collecting,
processing,
and
analyzing
a
representative
portion
of
the
resident
aquatic
community
to
determine
its
structural
and/
or
functional
characteristics
(
USEPA.
1991a.)

"
Biomagnification"
is
the
process
by
which
the
concentration
of
a
compound
increases
in
species
occupying
successive
trophic
levels
(
USEPA,
1991a.)

"
Cancer
potency
slope
factor"
(
q1*)
is
an
indication
of
a
chemical's
human
cancer­
causing
potential
derived
using
animal
studies
or
epidemiological
data
on
human
exposure;
based
on
extrapolation
of
high­
dose
levels
over
short
periods
of
time
to
low­
dose
levels
and
a
lifetime
exposure
period
through
the
use
of
a
linear
model
(
USEPA,
1991a.)

"
Chronic"
defines
a
stimulus
that
lingers
or
continues
for
a
relatively
long
period
of
time,
often
one­
tenth
of
the
life
span
or
more.
Chronic
should
be
considered
a
relative
term
depending
on
the
life
span
of
an
organism.
The
measurement
of
a
chronic
effect
can
be
reduced
growth,
reduced
reproduction,
etc.,
in
addition
to
lethality
(
USEPA,
1991a.)

"
Community
component"
is
a
general
term
that
may
pertain
to
the
biotic
guild
(
fish,
invertebrates,

algae),
the
taxonomic
category
(
order,
family,
genus,
species),
the
feeding
strategy
(
herbivore,
omnivore,
predator),
or
the
organizational
level
(
individual,
population,
assemblage)
of
a
biological
entity
within
the
aquatic
community
(
USEPA,
1991a.)

GLOSS­
2
(
9/
15/
93)
Glossan
"
Completely
mixed
condition"
is
defined
as
no
measurable
difference
in
the
concentration
of
a
pollutant
exists
across
a
transect
of
the
water
body
(
e.
g.,
does
not
vary
by
5%)
(
LJSITA.
1991a.)

"
Criteria"
are
elements
of
State
water
quality
standards,
expressed
as
constituent
concentrations,
levels,
or
narrative
statements,
representing
a
quality
of
water
that
supports
a
particular
use.
When
criteria
are
met,
water
quality
will
generally
protect
the
designated
use
(
40
CFR
131.3.)

"
Criteria
continuous
concentration"
(
CCC)
is
the
EPA
national
water
quality
criteria
recommendation
for
the
highest
instream
concentration
of
a
toxicant
or
an
effluent
to
which
organisms
can
be
exposed
indefinitely
without
causing
unacceptable
effect
(
USEPA,
1991a.)

"
Criteria
maximum
concentration"
(
CMC)
is
the
EPA
national
water
quality
criteria
recommendation
for
the
highest
instream
concentration
of
a
toxicant
or
an
effluent
to
which
organisms
can
be
exposed
for
a
brief
period
of
time
without
causing
an
acute
effect
(
USEPA,
1991a.)

"
Critical
life
stage"
is
the
period
of
time
in
an
organism's
lifespan
in
which
it
is
the
most
susceptible
to
adverse
effects
caused
by
exposure
to
toxicants,
usually
during
early
development
(
egg,
embryo,
larvae).
Chronic
toxicity
tests
are
often
run
on
critical
life
stages
to
replace
long
duration,
life
cycle
tests
since
the
most
toxic
effect
usually
occurs
during
the
critical
life
stage
(
USEPA,
1991a.)

"
Critical
species"
is
a
species
that
is
commercially
or
recreationally
important
at
the
site,
a
species
that
exists
at
the
site
and
is
listed
as
threatened
or
endangered
under
section
4
of
the
Endangered
Species
Act,
or
a
species
for
which
there
is
evidence
that
the
loss
of
the
species
from
the
site
is
likely
to
cause
an
unacceptable
impact
on
a
commercially
or
recreationally
important
species,
a
threatened
or
endangered
species,
the
abundances
of
a
variety
of
other
species,
or
the
structure
or
function
of
the
community
(
USEPA,
1994a.)

"
Design
flow"
is
the
flow
used
for
steady­
state
waste
load
allocation
modeling
(
USEPA,
1991a.)

"
Designated
uses"
are
those
uses
specified
in
water
quality
standards
for
each
water
body
or
segment
whether
or
not
they
are
being
attained
(
40
CFR
13
1.3.)

"
Discharge
length
scale"
is
the
square
root
of
the
cross­
sectional
area
of
any
discharge
outlet
(
USEPA,
1991a.)

"
Diversity"
is
the
number
and
abundance
of
biological
taxa
in
a
specified
location
(
USEPA,
1991a.)

"
Effective
concentration"
(
EC)
is
a
point
estimate
of
the
toxicant
concentration
that
would
cause
an
observable
adverse
effect
(
such
as
death,
immobilization,
or
serious
incapacitation)
in
a
given
percentage
of
the
test
organisms
(
USEPA,
1991a.)

"
Existing
uses"
are
those
uses
actually
attained
in
the
water
body
on
or
after
November
28,
1975,
whether
or
not
they
are
included
in
the
water
quality
standards
(
40
CFR
13
1.3.)

(
8/
15/
94)
GLOSS­
3
Water
Quality
Standards
Handbook
­
Second
Edition
"
Federal
Indian
Reservation,
"
"
Indian
Reservation,"
or
"
Reservation"
is
defined
as
all
land
within
the
limits
of
any
Indian
reservation
under
the
jurisdiction
of
the
United
States
Government,
notwithstanding
the
issuance
of
any
patent,
and
including
rights­
of­
way
running
through
the
reservation
(
40
CFR
131.3.)

"
Final
acute
value"
(
FAV)
is
an
estimate
of
the
concentration
of
the
toxicant
corresponding
to
a
cumulative
probability
of
0.05
in
the
acute
toxicity
values
for
all
genera
for
which
acceptable
acute
tests
have
been
conducted
on
the
toxicant
(
USEPA,
1991a.)

"
Frequency"
is
how
often
criteria
can
be
exceeded
without
unacceptably
affecting
the
community
(
USEPA,
1991a.)

"
Harmonic
mean
flow"
is
the
number
of
daily
flow
measurements
divided
by
the
sum
of
the
reciprocals
of
the
flows.
That
is,
it
is
the
reciprocal
of
the
mean
of
reciprocals
(
USEPA,
1991a.)

"
Indian
Tribe"
or
"
Tribe"
describes
any
Indian
Tribe,
band,
group,
or
community
recognized
by
the
Secretary
of
the
Interior
and
exercising
governmental
authority
over
a
Federal
Indian
reservation
(
40
CFR
131.3.)

"
Inhibition
concentration"
(
IC)
is
a
point
estimate
of
the
toxicant
concentration
that
would
cause
a
given
percent
reduction
(
e.
g.,
IC25)
in
a
non­
lethal
biological
measurement
of
the
test
organisms,
such
as
reproduction
or
growth
(
USEPA,
1991a.)

"
Lethal
concentration"
is
the
point
estimate
of
the
toxicant
concentration
that
would
be
lethal
to
a
given
percentage
of
the
test
organisms
during
a
specified
period
(
USEPA,
1991a.)

"
Lipophilic"
is
a
high
affinity
for
lipids
(
fats)
(
USEPA,
1991a.)

"
Load
allocations"
(
LA)
the
portion
of
a
receiving
water
TMDL
that
is
attributed
either
lo
one
of
its
existing
or
future
nonpoint
sources
of
pollution
or
to
natural
background
sources
(
USEPA,
1991a.)

"
Lowest­
observed­
adverse­
effect­
level"
(
LOAEL)
is
the
lowest
concentration
of
an
effluent
or
toxicant
that
results
in
statistically
significant
adverse
health
effects
as
observed
in
chronic
or
subchronic
human
epidemiology
studies
or
animal
exposure
(
USEPA,
1991a.)

"
Magnitude"
is
how
much
of
a
pollutant
(
or
pollutant
parameter
such
as
toxicity),
expressed
as
a
concentration
or
toxic
unit
is
allowable
(
USEPA,
1991a.)

"
Minimum
level"
(
ML)
refers
to
the
level
at
which
the
entire
analytical
system
gives
recognizable
mass
spectra
and
acceptable
calibration
points
when
analyzing
for
pollutants
of
concern.
This
level
corresponds
to
the
lowest
point
at
which
the
calibration
curve
is
determined
(
USEPA,
1991a.)

"
Mixing
zone"
is
an
area
where
an
effluent
discharge
undergoes
initial
dilution
and
is
extended
to
cover
the
secondary
mixing
in
the
ambient
water
body.
A
mixing
zone
is
an
allocated
impact
zone
where
water
quality
criteria
can
be
exceeded
as
long
as
acutely
toxic
conditions
are
prevented
(
USEPA,
1991a.)

GLOSS­
4
(
8/
15/
94)
Glossary
"
Navigable
waters"
refer
to
the
waters
of
the
United
States,
including
the
territorial
seas
(
33
USC
1362.)

"
No­
observed­
adverse­
effect­
level"
(
TVOAEL)
is
a
tested
dose
of
an
effluent
or
a
toxicant
below
which
no
adverse
biological
effects
are
observed,
as
identified
from
chronic
or
subchronic
human
epidemiology
studies
or
animal
exposure
studies
(
USEPA,
1991a.)

"
No­
observed­
effect­
concentration"
(
NOEC)
is
the
highest
tested
concentration
of
an
effluent
or
a
toxicant
at
which
no
adverse
effects
are
observed
on
the
aquatic
test
organisms
at
a
specific
time
of
observation.
Determined
using
hypothesis
testing
(
USEPA,
1991a.)

"
Nonthreshotd
effects"
are
associated
with
exposure
to
chemicals
that
have
no
safe
exposure
levels.
(
i.
e.,
cancer)
(
USEPA,
1991a.)

"
Persistent
pollutant"
is
not
subject
to
decay,
degradation,
transformation,
volatilization,
hydrolysis,
or
photolysis
(
USEPA,
1991a.)

"
Pollution"
is
defined
as
the
man­
made
or
man­
induced
alteration
of
the
chemical,
physical,
biological
and
radiological
integrity
of
water
(
33
USC
1362.)

"
Priority
po1Mant.
s"
are
those
pollutants
listed
by
the
Administrator
under
section
307(
a)
of
the
Act
(
USEPA,
1991a.)

"
Reference
ambient
concentration"
(
RAC)
is
the
concentration
of
a
chemical
in
water
which
will
not
cause
adverse
impacts
to
human
health;
RAC
is
expressed
in
units
of
mg/
l
(
USEPA,
1991a.)

"
Reference
conditions"
describe
the
characteristics
of
water
body
segments
least
impaired
by
human
activities.
As
such,
reference
conditions
can
be
used
to
describe
attainable
biological
or
habitat
conditions
for
water
body
segments
with
common
watershed/
catchment
characteristics
within
defined
geographical
regions.

"
Reference
tissue
concentration"
(
RTC)
is
the
concentration
of
a
chemical
in
edible
fish
or
shellfish
tissue
which
will
not
cause
adverse
impacts
to
human
health
when
ingested.
RTC
is
expressed
in
units
of
mg/
kg
(
USEPA,
1991a.)

"
Reference
dose"
(
Rfl))
is
an
estimate
of
the
daily
exposure
to
human
population
that
is
likely
to
be
without
appreciable
risk
of
deleterious
effect
during
a
lifetime;
derived
from
NOAEL
or
LOAEL
(
USEPA,
1991a.)

"
Section
304(
a)
criteria"
are
developed
by
EPA
under
authority
of
section
304(
a)
of
the
Act
based
on
the
latest
scientific
information
on
the
relationship
that
the
effect
of
a
constituent
concentration
has
on
particular
aquatic
species
and/
or
human
health.
This
information
is
issued
periodically
to
the
States
as
guidance
for
use
in
developing
criteria
(
40
CFR
131.3.)

"
Site­
specific
aquatic
life
criterion"
is
a
water
quality
criterion
for
aquatic
life
that
has
been
derived
to
be
specifically
appropriate
to
the
water
quality
characteristics
and/
or
species
composition
at
a
particular
location
(
USEPA,
1994a.)

(
8/
15/
94)
GLOSS­
S
ater
Quality
Standards
Handbook
­
Second
Edition
"
States"
include:
the
50
States,
the
District
of
Columbia,
Guam,
the
Commonwealth
of
Puerto
Rico,
Virgin
Islands,
American
Samoa,
the
Trust
Territory
of
the
Pacific
Islands,
and
the
Commonwealth
of
the
Northern
Mariana
Islands,
and
Indian
Tribes
that
EPA
determines
qualify
for
treatment
as
States
for
the
purposes
of
water
quality
standards
(
40
CFR
13
1.3.)

"
Steady­
state
model"
is
a
fate
and
transport
model
that
uses
constant
values
of
input
variables
to
predict
constant
values
of
receiving
water
quality
concentrations
(
USEPA,
1991a.)

"
STORET"
is
EPA's
computerized
water
quality
database
that
includes
physical,
chemical,
and
biological
data
measured
in
water
bodies
throughout
the
United
States
(
USEPA,
1991a.)

"
Sublethal"
refers
to
a
stimulus
below
the
level
that
causes
death
(
USEPA,
1991a.)

"
Synergism"
is
the
characteristic
property
of
a
mixture
of
toxicants
that
exhibits
a
greater­
than­
additive
total
toxic
effect
(
USEPA,
1991a.)

"
Threshold
effects"
result
from
chemicals
that
have
a
safe
level
(
i.
e..
acute,
subacute,
or
chronic
human
health
effects)
(
USEPA,
1991a.)

"
Total
maximum
daily
load"
(
TMDL)
is
the
sum
of
the
individual
waste
load
allocations
(
WLAs)
and
load
allocations
(
LAS);
a
margin
of
safety
is
included
with
the
two
types
of
allocations
so
that
any
additional
loading,
regardless
of
source,
would
not
produce
a
violation
of
water
quality
standards
(
USEPA,
1991a.)

"
Toxicity
test"
is
a
procedure
to
determine
the
toxicity
of
a
chemical
or
an
effluent
using
living
organisms.
A
toxicity
test
measures
the
degree
of
effect
on
exposed
test
organisms
of
a
specific
chemical
or
effluent
(
USEPA,
1991a.)

"
Toxic
pollutant"
refers
to
those
pollutants,
or
combination
of
pollutants,
including
disease­
causing
agents,
which
after
discharge
and
upon
exposure,
ingestion,
inhalation,
or
assimilation
into
any
organism.
either
directly
from
the
environment
or
indirectly
by
ingestion
through
food
chains,
will.
or
on
the
basis
of
information
available
to
the
administrator,
cause
death,
disease,
behavioral
abnormalities,
cancer,
genetic
mutations,
physiological
malfunctions
(
including
malfunctions
in
reproduction)
or
physical
deformations,
in
such
organisms
or
their
offspring
(
33
llSC
section
1362.)

"
Toxic
units"
(
TUs)
are
a
measure
of
toxicity
in
an
effluent
as
determined
by
the
acute
toxicity
units
(
T1'
a)
or
chronic
toxicity
units
(
TUc)
measured
(
USEPA,
1991a.)

"
Toxic
unit
acute"
(
TUa)
is
the
reciprocal
of
the
effluent
concentration
that
causes
50
percent
of
the
organisms
to
die
by
the
end
of
the
acute
exposure
period
(
i.
e.,
lOO/
LC&
(
USEPA,
1991a.)

"
Toxic
unit
chronic"
(
TUc)
is
the
reciprocal
of
the
effluent
concentration
that
causes
no
observable
effect
on
the
test
organisms
by
the
end
of
the
chronic
exposure
period
(
i.
e.,
lOO/
NOEC)
(
ITSEPA.
1991a.)

GLOSS­
6
(
8/
15/
94)
Glossay
"
Use
attainability
analysis"
(
UAA)
is
a
structured
scientific
assessment
of
the
factors
affecting
the
attainment
of
the
use
which
may
include
physical,
chemical,
biological,
and
economic
factors
as
described
in
section
131.10(
g)
(
40
CFR
131.3.)

"
Waste
load
allocation"
(
WLA)
is
the
portion
of
a
receiving
water's
TMDL
that
is
allocated
to
one
of
its
existing
or
future
point
sources
of
pollution
(
USEPA,
1991a.)

"
Waters
of
the
United
States"
refer
to:

(
1)

(
2)

(
3)

(
4)

(
5)

(
6)

(
7)
all
waters
which
are
currently
used,
were
used
in
the
past,
or
may
be
susceptible
to
use
in
interstate
or
foreign
commerce,
including
all
waters
which
are
subject
to
the
ebb
and
flow
of
the
tide;

all
interstate
waters,
including
interstate
wetlands;

all
other
waters
such
as
intrastate
lakes,
rivers,
streams
(
including
intermittent
streams).
mudflats,
sandflats,
wetlands,
sloughs,
prairie
potholes.
wet
meadows,
playa
lakes.
or
natural
ponds
the
use
or
degradation
of
which
would
affect
or
could
affect
interstate
or
foreign
commerce,
including
any
such
waters:

(
9
which
are
or
could
be
used
by
interstate
or
foreign
travelers
for
recreational
or
other
purposes;

(
ii)
from
which
fish
or
shellfish
are
or
could
be
taken
and
sold
in
interstate
or
foreign
commerce;
or
(
iii)
which
are
or
could
be
used
for
industrial
purposes
by
industries
in
interstate
commerce.

all
impoundments
of
waters
otherwise
defined
as
waters
of
the
United
States
under
this
definition;

tributaries
of
waters
in
paragraphs
(
1)
through
(
4)
of
this
definition;

the
territorial
sea;
and
wetlands
adjacent
to
waters
(
other
than
waters
that
are
themselves
wetlands)
identified
in
paragraphs
(
1)
through
(
6)
of
this
definition.
"
Wetlands"
are
defined
as
those
areas
that
are
inundated
or
saturated
by
surface
or
groundwater
at
a
frequency
and
duration
sufficient
to
support,
and
that
under
normal
circumstances
do
support,
a
prevalence
of
vegetation
typically
adapted
for
life
in
saturated
soil
conditions.
Wetlands
generalI)
include
swamps,
marshes,
bogs,
and
similar
areas.

Waste
treatment
systems,
including
treatment
ponds
or
lagoons
designed
to
meet
the
requirements
of
the
Act
(
other
than
cooling
ponds
as
defined
in
40
CFR
423.
I
l(
m)
which
also
meet
the
criteria
for
this
definition)
are
not
waters
of
the
United
States.
(
40
CFR
232.2.)

(
8/
15/
W)
GI,
OSS­
7
Water
Quality
Standards
Handbook
­
Second
Edition
"
Water­
effect
ratio"
(
WER)
is
an
appropriate
measure
of
the
toxicity
of
a
material
obtained
in
a
site
water
divided
by
the
same
measure
of
the
toxicity
of
the
same
material
obtained
simultaneously
in
a
laboratory
dilution
water
(
USEPA,
1994a.)

"
Water
quality
assessment"
is
an
evaluation
of
the
condition
of
a
water
body
using
biological
surveys,
chemical­
specific
analyses
of
pollutants
in
water
bodies,
and
toxicity
tests
(
USEPA,
1991a.)

"
Water
quality
limited
segment"
refers
to
any
segment
where
it
is
known
that
water
quality
does
not
meet
applicable
water
quality
standards
and/
or
is
not
expected
to
meet
applicable
water
quality
standards
even
after
application
of
technology­
based
effluent
limitations
required
by
sections
301(
b)(
l)(
A)
and
(
B)
and
306
of
the
Act
(
40
CFR
131.3.)

"
Water
quality
standards"
(
WQS)
are
provisions
of
State
or
Federal
law
which
consist
of
a
designated
use
or
uses
for
the
waters
of
the
United
States,
water
quality
criteria
for
such
waters
based
upon
such
uses.
Water
quality
standards
are
to
protect
public
health
or
welfare,
enhance
the
quality
of
the
water
and
serve
the
purposes
of
the
Act
(
40
CFR
13
1.3.)

"
Whok­
efIluent
toxicity"
is
the
total
toxic
effect
of
an
effluent
measured
directly
with
a
toxicity
test
(
USEPA,
1991a.)

GLOSS­
8
(
8/
15/!­
M)
