United
States
Court
of
Appeals,
Tenth
Circuit.

AMERICAN
WILDLANDS;
Pacific
Rivers
Council;
Montana
Environmental
Information
Center
and
Northern
Plains
Resource
Council,
Inc.,
Plaintiffs­
Appellants,
v.
Carol
BROWNER,
in
her
official
capacity
as
the
Administrator
of
the
U.
S.
Environmental
Protection
Agency;
Bill
Yellowtail,
in
his
official
capacity
as
the
Regional
Administrator
of
the
U.
S.
Environmental
Protection
Agency,
Region
VIII
and
Environmental
Protection
Agency,
an
agency
of
the
United
States
Government,
Defendants­
Appellees.
and
Western
Environmental
Trade
Association,
on
behalf
of
its
members
and
State
of
Montana,
Department
of
Environmental
Quality,
Intervenors­
Appellees.

No.
00­
1224.

Aug.
8,
2001.

Environmental
organization
brought
action
challenging
Environmental
Protection
Agency's
(
EPA)
approval
pursuant
to
Clean
Water
Act
of
certain
of
Montana's
water
quality
standards.
The
United
States
District
Court
for
the
District
of
Colorado,
Kane,
Senior
Judge,
94
F.
Supp.
2d
1150,
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held
in
favor
of
EPA,
and
organization
appealed.
The
Court
of
Appeals,
Tacha,
Chief
Judge,
held
that:
(
1)
state
was
not
required
to
regulate
nonpoint
sources
at
antidegradation
stage,
and
(
2)
water
quality
standard
exempting
mixing
zones
from
compliance
with
narrative
water
quality
criteria
did
not
violate
Clean
Water
Act.

Affirmed.

West
Headnotes
[
1]
Environmental
Law
682
149Ek682
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149EK682>
(
Formerly
199k25.15(
8)
Health
and
Environment)

Environmental
Protection
Agency's
(
EPA)
approval
of
state's
water
quality
standards
pursuant
to
Clean
Water
Act
is
entitled
to
deference,
and
will
be
upheld
if
its
action
is
permissible
construction
of
statute.
Federal
Water
Pollution
Control
Act
Amendments
of
1972,
§
303,
33
U.
S.
C.
A.
§
1313
<
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[
2]
Environmental
Law
175
149Ek175
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1.0&
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149EK175>
(
Formerly
199k25.7(
3)
Health
and
Environment)

Environmental
Protection
Agency
(
EPA)
did
not
have
authority
under
Clean
Water
Act
to
regulate
nonpoint
source
pollution.
Federal
Water
Pollution
Control
Act
Amendments
of
1972,
§
303,
33
U.
S.
C.
A.
§
1313
<
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westlaw.
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rs=++++
1.0&
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[
3]
Environmental
Law
191
149Ek191
<
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KeyNumber/
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wl?
rs=++++
1.0&
vr=
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KEY&
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149EK191>
(
Formerly
199k25.7(
6.1)
Health
and
Environment)

State
was
not
required
under
Clean
Water
Act
to
regulate
nonpoint
sources
at
antidegradation
stage.
Federal
Water
Pollution
Control
Act
Amendments
of
1972,
§
303,
33
U.
S.
C.
A.
§
1313
<
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com/
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wl?
rs=++++
1.0&
vr=
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&
FindType=
L>;
40
C.
F.
R.
§
131.12(
a)(
2)
<
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Default.
wl?
rs=++++
1.0&
vr=
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[
4]
Environmental
Law
191
149Ek191
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Default.
wl?
rs=++++
1.0&
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(
Formerly
199k25.7(
12)
Health
and
Environment)

[
4]
Environmental
Law
190
149Ek190
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wl?
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1.0&
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(
Formerly
199k25.7(
12)
Health
and
Environment)

Montana's
water
quality
standard
exempting
mixing
zones
from
compliance
with
narrative
water
quality
criteria
and
state's
antidegradation
rules
did
not
violate
Clean
Water
Act
(
CWA),
where
state
provided
number
of
safeguards
to
ensure
that
mixing
zones
did
not
damage
water
quality
of
entire
water
body.
Federal
Water
Pollution
Control
Act
Amendments
of
1972,
§
303,
33
U.
S.
C.
A.
§
1313
<
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40
C.
F.
R.
§
131.13
<
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1.0&
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1000547&
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&
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L>;
MCA
75­
5­
301(
4).
*
1193
Kristen
L.
Boyles,
<
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Default.
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rs=++++
1.0&
vr=
2.0&
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WLDPEOPLECITE
DocName=
0212045001&
FindType=
h>
Earthjustice
Legal
Defense
Fund,
(
Stephen
D.
Mashuda,
Earthjustice
Legal
Defense
Fund,
Seattle,
WA,
and
James
S.
Angell,
Earthjustice
Legal
Defense
Fund,
Denver,
CO,
with
her
on
the
briefs),
for
Appellants.

Robert
H.
Oakley,
(
Lois
J.
Schiffer,
Assistant
Attorney
General,
David
A.
Carson
and
Greer
S.
Goldman,
with
him
on
the
brief),
United
States
Department
of
Justice,
Environment
&
Natural
Resources
Division,
Washington,
DC,
for
Appellee
Environmental
Protection
Agency.

Claudia
L.
Massman,
Special
Assistant
Attorney
General,
Department
of
Environmental
Quality,
Helena,
MT,
for
Appellee
State
of
Montana.

Rebecca
W.
Watson,
Gough,
Shanahan,
Johnson
&
Waterman,
and
John
Bloomquist
<
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Default.
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rs=++++
1.0&
vr=
2.0&
DB=
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PEOPLECITE&
DocName=
0253484101&
FindType=
h>,
Doney,
Crowley,
Bloomquist
&
Uda,
Helena,
MT,
filed
a
brief,
on
behalf
of
Appellee
Western
Environmental
Trade
Association.

Before
TACHA
<
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rs=++++
1.0&
vr=
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DocName=
0209742301&
FindType=
h>,
Chief
Judge,
REAVLEY
<
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Default.
wl?
rs=++++
1.0&
vr=
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[
FN*]
and
LUCERO
<
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Default.
wl?
rs=++++
1.0&
vr=
2.0
&
DB=
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DocName=
0255848601&
FindType=
h>,
Circuit
Judges.

FN*
Honorable
Thomas
M.
Reavley,
Senior
Circuit
Judge,
United
States
Court
of
Appeals
for
the
Fifth
Circuit,
sitting
by
designation.

TACHA
<
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rs=++++
1.0&
vr=
2.0&
DB=
WLD­
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DocName=
0209742301&
FindType=
h>,
Chief
Circuit
Judge.
This
appeal
presents
a
challenge
by
Appellant
American
Wildlands
to
the
Environmental
Protection
Agency's
("
the
EPA")
approval
pursuant
to
the
Clean
Water
Act
of
certain
of
Montana's
water
quality
standards.
Specifically,
two
questions
are
presented
to
this
court
for
review:
(
1)
whether
the
EPA
properly
approved
Montana's
statutory
exemption
from
antidegradation
review
of
nonpoint
sources
of
pollution;
and
(
2)
whether
the
EPA
properly
approved
Montana's
mixing
zone
policies
and
procedures.
The
district
court
held
in
favor
of
the
EPA.
We
exercise
jurisdiction
pursuant
to
28
U.
S.
C.
§
1291
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and
affirm.

I.
Statutory
and
Regulatory
Scheme
A.
Point
and
Nonpoint
Source
Discharges
The
Clean
Water
Act
("
the
Act")
was
adopted
"
to
restore
and
maintain
the
chemical,
physical,
and
biological
integrity
of
the
Nation's
waters."
33
U.
S.
C.
§
1251(
a)
<
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To
achieve
this
goal,
Congress
prohibited
the
discharge
from
a
point
source
of
any
pollutant
into
the
waters
of
the
United
States
unless
that
discharge
met
specific
requirements
set
forth
in
the
Act.
33
U.
S.
C.
§
1311(
a)
<
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"
Point
source"
is
defined
by
the
Act
to
mean:
"
any
discernible,
confined
and
discrete
conveyance
...
from
which
pollutants
are
or
may
be
discharged."
33
U.
S.
C.
§
1362(
14)
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Further,
a
"
pollutant"
is
defined
as
"
dredged
spoil,
solid
waste,
incinerator
residue,
sewage,
garbage,
sewage
sludge,
munitions,
chemical
wastes,
biological
materials,
radioactive
materials,
heat,
wrecked
or
discarded
equipment,
rock,
sand,
cellar
dirt
and
industrial,
municipal,
and
agricultural
waste
discharged
into
water."
33
U.
S.
C.
§
1362(
6)
<
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Default.
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rs=++++
1.0&
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DB=
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In
order
for
point
source
discharges
to
be
in
compliance
with
the
Act,
such
discharges
must
adhere
to
the
terms
of
a
National
Pollutant
Discharge
Elimination
System
("
NPDES")
permit
issued
pursuant
to
the
Act.
33
U.
S.
C.
§
1342
<
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&
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NPDES
permits
are
issued
by
the
EPA
or,
in
certain
jurisdictions,
by
state
agencies
authorized
to
do
so
by
the
EPA.
33
U.
S.
C.
§
1342(
a)­(
d)
<
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Unlike
point
source
discharges,
nonpoint
source
discharges
are
not
defined
by
the
Act.
One
court
has
described
nonpoint
source
pollution
as
"
nothing
more
that
a
[
water]
pollution
problem
not
involving
a
discharge
from
a
point
source."
*
1194Nat'l
Wildlife
Federation
v.
Gorsuch,
<
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693
F.
2d
156,
166
n.
28
(
D.
C.
Cir.
1982)
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&
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1982148238&
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166>
(
internal
quotation
marks
omitted).

Rather
than
vest
the
EPA
with
authority
to
control
nonpoint
source
discharges
through
a
permitting
process,
Congress
required
states
to
develop
water
quality
standards
for
intrastate
waters.
33
U.
S.
C.
§
1313
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1.0&
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&
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Water
quality
standards
consist
of
three
elements:
first,
each
water
body
must
be
given
a
"
designated
use,"
such
as
recreation
or
the
protection
of
aquatic
life;
second,
the
standards
must
specify
for
each
body
of
water
the
amounts
of
various
pollutants
or
pollutant
parameters
that
may
be
present
without
impairing
the
designated
use;
and
finally,
each
state
must
adopt
an
antidegradation
review
policy
which
will
allow
the
state
to
assess
activities
that
may
lower
the
water
quality
of
the
water
body.
33
U.
S.
C.
§
1313(
c)(
2)(
A)
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40
C.
F.
R.
§
§
130.3
<
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rs=++++
1.0&
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2.0&
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1000547&
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40CFRS130.3&
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L>,
130.10(
d)(
4)
<
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rs=++++
1.0&
vr=
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131.6
<
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
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1000547&
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40CFRS131.6
&
FindType=
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131.10
<
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westlaw.
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000547
&
DocName=
40CFRS131.10&
FindType=
L>,
131.11
<
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000547&
DocName=
40CFRS131.11&
FindType=
L>.
Further,
each
state
is
required
to
identify
all
of
the
waters
within
its
borders
not
meeting
water
quality
standards
and
establish
"
total
maximum
daily
loads"
("
TMDL")
for
those
waters.
33
U.
S.
C.
§
1313(
d)
<
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000546&
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L>.
A
TMDL
defines
the
specified
maximum
amount
of
a
pollutant
which
can
be
discharged
into
a
body
of
water
from
all
sources
combined.
Dioxin/
Organochlorine
Ctr.
v.
Clarke,
<
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rs=++++
1.0&
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506
&
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SerialNum=
1995133453&
ReferencePosition=
1520>
57
F.
3d
1517,
1520
(
9th
Cir.
1995)
<
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westlaw.
com/
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1995133453&
ReferencePosition=
1520>.

B.
The
EPA's
Approval
Role
Whenever
a
state
revises
or
adopts
a
water
quality
standard,
the
state
must
submit
the
standard
to
the
EPA's
Regional
Administrator
for
a
determination
as
to
whether
the
new
standard
is
consistent
with
the
Act.
33
U.
S.
C.
§
1313(
c)(
2)
<
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1.0&
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L>;
40
C.
F.
R.
§
131.21(
a)
<
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com/
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Default.
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rs=++++
1.0
&
vr=
2.0&
DB=
1000547&
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40CFRS131.21&
FindType=
L>.
The
EPA
must
either
approve
the
standard
within
sixty
days
of
submission
or­­
if
the
EPA
determines
that
the
standard
is
inconsistent
with
the
Act­­
disapprove
the
standard
and
notify
the
state
of
any
changes
necessary
to
gain
the
EPA's
approval.
33
U.
S.
C.
§
1313(
c)(
3)
<
http://
www.
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Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000546&
DocName=
33USCAS1313
&
FindType=
L>.
If
the
state
fails
to
make
the
changes
required
by
the
EPA,
the
agency
must
promptly
promulgate
and
impose
replacement
standards
upon
the
state.
33
U.
S.
C.
§
1313(
c)(
3)­(
4)(
A)
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000546&
DocName=
33USCAS1313
&
FindType=
L>.

"
'[
S]
tates
have
the
primary
role,
under
§
303
of
the
CWA
(
33
U.
S.
C.
§
1313)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000546&
DocName=
33USCAS1313
&
FindType=
L>,
in
establishing
water
quality
standards.
EPA's
sole
function,
in
this
respect,
is
to
review
those
standards
for
approval.'
"
City
of
Albuquerque
v.
Browner,
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1996226465&
ReferencePosition=
425>
97
F.
3d
415,
425
(
10th
Cir.
1996)
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1996226465&
ReferencePosition=
425>
(
quoting
Natural
Res.
Def.
Council,
Inc.
v.
EPA,
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1994048161&
ReferencePosition=
1401>
16
F.
3d
1395,
1401
(
4th
Cir.
1993)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1994048161&
ReferencePosition=
1401>).
Therefore,
the
EPA
has
a
limited
role
in
reviewing
water
quality
standards.
Id.
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
FindType=
Y&
SerialNum=
1996226465>
("
Congress
clearly
intended
the
EPA
to
have
a
limited,
non­
rulemaking
role
in
the
establishment
of
water
quality
standards
by
states....").

C.
Antidegradation
The
antidegradation
review
policies
adopted
by
the
states
as
a
part
of
their
water
quality
standards
must
be
consistent
with
the
federal
antidegradation
policy.
40
C.
F.
R.
§
131.12
<
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com/
Find/
Default.
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rs=++++
1.0&
vr=
2.0&
DB=
1000547&
DocName=
40CFRS131.12&
FindType=
L>.
The
EPA's
regulations
establish
three
levels
of
water
quality
protection:
Tier
I,
Tier
II,
and
Tier
III.
Tier
I
protection
establishes
the
minimum
water
quality
standard
for
all
waters
and
requires
that
"[
e]
xisting
instream
water
uses
and
the
level
of
water
quality
necessary
to
protect
the
existing
uses
shall
be
maintained
and
protected."
40
C.
F.
R.
<
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000547&
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&
FindType=
L>
§
131.12(
a)(
1)
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000547
&
DocName=
40CFRS131.12&
FindType=
L>.
Tier
II
protection
provides
that,
where
the
water
quality
of
a
water
body
exceeds
that
necessary
to
support
aquatic
life
and
recreation,
that
level
of
water
quality
shall
be
maintained
unless
the
state
determines
that
"
allowing
lower
water
quality
is
necessary
to
accommodate
important
economic
or
social
development
in
the
area
in
which
the
waters
are
located."
40
C.
F.
R.
§
131.12(
a)(
2)
<
http://
www.
westlaw.
com/
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Default.
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rs=++++
1.0&
vr=
2.0&
DB=
1000547&
DocName=
40CFRS131.12
&
FindType=
L>.
Tier
III
protection
provides
that,
where
a
water
body
"
constitute[
s]
an
outstanding
National
resource,
such
as
waters
of
National
and
State
parks
and
wildlife
refuges
and
waters
*
1195
of
exceptional
recreational
or
ecological
significance,
that
water
quality
shall
be
maintained
and
protected."
40
C.
F.
R.
§
131.12(
a)
(
3)
<
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Find/
Default.
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rs=++++
1.0&
vr=
2.0&
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1000547&
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40CFRS131.12
&
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L>.

D.
Mixing
Zones
Pursuant
to
the
EPA's
regulations,
a
state
may,
at
its
discretion,
include
within
its
water
quality
standards
"
policies
generally
affecting
...
mixing
zones."
40
C.
F.
R.
§
131.13
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0
&
vr=
2.0&
DB=
1000547&
DocName=
40CFRS131.13&
FindType=
L>.
Mixing
zones
are
"
areas
where
an
effluent
discharge
undergoes
initial
dilution
and
are
extended
to
cover
the
secondary
mixing
in
the
ambient
water
body.
A
mixing
zone
is
an
allocated
impact
zone
where
acute
and
chronic
water
quality
criteria
can
be
exceeded
as
long
as
a
number
of
protections
are
maintained."
Environmental
Protection
Agency,
Water
Quality
Standards
Handbook
§
5.1.1,
at
5­
5
(
2d
ed.
1994)
(
hereinafter
Handbook
).
The
protections
that
must
be
maintained
include
the
absence
of
"
toxic
conditions
to
aquatic
life,"
"
objectionable
deposits,"
"
floating
debris,"
"
objectionable
color,
odor,
taste,
or
turbidity,"
and
substances
resulting
in
"
a
dominance
of
nuisance
species."
Id.
at
5­
5
to
5­
6.
Mixing
zones
are
allowable
as
a
practical
necessity
because
"[
i]
t
is
not
always
necessary
to
meet
all
water
quality
criteria
within
the
discharge
pipe
to
protect
the
integrity
of
the
water
body
as
a
whole.
Sometimes
it
is
appropriate
to
allow
for
ambient
concentrations
above
the
criteria
in
small
areas
near
outfalls."
Id.
§
5.1,
at
5­
1.
Should
a
state
decide
to
include
"
policies
generally
affecting
...
mixing
zones"
within
their
water
quality
standards,
those
policies
are
subject
to
review
and
approval
by
the
EPA.
40
C.
F.
R.
§
131.13
<
http://
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com/
Find/
Default.
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rs=++++
1.0
&
vr=
2.0&
DB=
1000547&
DocName=
40CFRS131.13&
FindType=
L>.

E.
Montana's
Policies
1.
Montana's
Exemption
of
Nonpoint
Source
Pollution
from
Antidegradation
Review
In
drafting
its
water
quality
standards,
the
Montana
legislature
exempted
"
existing
activities
that
are
nonpoint
sources
of
pollution
as
of
April
29,
1993"
from
antidegradation
review
with
respect
to
Tier
II
waters.
Mont.
Code
Ann.
§
75­
5­
317(
2)(
a)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1002018
&
DocName=
MTST75­
5­
317&
FindType=
L>.
Further,
nonpoint
sources
initiated
after
April
29,
1993
are
exempted
from
antidegradation
review
with
respect
to
Tier
II
waters
"
when
reasonable
land,
soil,
and
water
conservation
practices
are
applied
and
existing
and
anticipated
beneficial
uses
will
be
fully
protected."
Mont.
Code
Ann.
§
75­
5­
317(
2)(
b)
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1002018
&
DocName=
MTST75­
5­
317&
FindType=
L>.

2.
Montana's
Mixing
Zone
Policies
and
Procedures
Montana's
antidegradation
rules
provide
that,
where
degradation
to
a
water
body
at
the
edge
of
a
mixing
zone
is
not
significant,
no
antidegradation
review
of
the
mixing
zone
itself
is
required.
Mont.
Admin.
R.
§
17.30.715(
1)(
c)
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1012680&
DocName=
MTADC17.30.715
&
FindType=
L>,
17.30.505(
1)(
b)
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1012680
&
DocName=
MTADC17.30.505&
FindType=
L>.
Montana
does,
however,
impose
a
number
of
other
requirements
on
mixing
zones
designed
to
limit
their
impact
on
the
receiving
water
body.
Montana
requires
that
mixing
zones
have
"(
a)
the
smallest
practicable
size,
(
b)
a
minimum
practicable
effect
on
water
uses,
and
(
c)
definable
boundaries."
Mont.
Code
Ann.
§
75­
5­
301(
4)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0
&
DB=
1002018&
DocName=
MTST75­
5­
301&
FindType=
L>.
A
mixing
zone
may
not
"
threaten
or
impair
existing
beneficial
uses."
Mont.
Admin.
R.
§
17.30.506(
1)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0
&
DB=
1012680&
DocName=
MTADC17.30.506&
FindType=
L>.
A
discharge
permit
may
not
be
renewed
if
"
there
is
evidence
that
the
previously
allowed
mixing
zone
will
impair
existing
or
anticipated
uses."
Mont.
Admin.
R.
§
17.30.505(
1)(
c)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1012680
&
DocName=
MTADC17.30.505&
FindType=
L>.
The
Montana
Department
of
Environmental
Quality
is
required
to
consider
various
factors
in
deciding
whether
or
not
to
grant
a
mixing
zone,
such
as
the
toxicity
and
persistence
of
the
substance
being
discharged
and
the
cumulative
effects
of
multiple
mixing
zones.
Mont.
Admin.
R.
§
17.30.506
(
2)
<
http://
www.
westlaw.
com/
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1012680&
DocName=
MTADC17.30.506
&
FindType=
L>.
Finally,
the
water
quality
within
the
mixing
zone
itself
is
regulated
to
prohibit
discharge
from
blocking
passage
of
aquatic
organisms
or
from
causing
the
death
of
*
1196
organisms
passing
through
the
mixing
zone.
Mont.
Admin.
R.
§
17.30.602(
14)
<
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www.
westlaw.
com/
Find/
Default.
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rs=++++
1.0&
vr=
2.0&
DB=
1012680&
DocName=
MTADC17.30.602&
FindType=
L>.
II.
Proceedings
Below
American
Wildlands
filed
this
lawsuit
in
1998,
alleging
that
the
EPA
had
failed
to
take
timely
action
under
section
303(
c)
of
the
Act
to
approve
or
disapprove
Montana's
new
and
revised
water
quality
standards.
The
original
complaint
alleged
that
the
EPA
violated
the
Act
by:
(
1)
failing
to
approve
or
disapprove
Montana's
new
and
revised
water
quality
standards;
and
(
2)
by
failing
to
promptly
prepare
and
promulgate
replacement
standards
for
those
Montana
standards
that
failed
to
meet
the
requirements
of
the
Act.
In
October
1998,
American
Wildlands
moved
for
summary
judgment.
The
parties
stayed
briefing
of
that
motion,
however,
when
the
EPA
stipulated
that
it
would
complete
its
review
of
Montana's
water
quality
standards
by
January
15,
1999.

On
December
24,
1998,
the
EPA
disapproved
some
of
Montana's
revised
standards
and
approved
others.
The
EPA
addressed
the
remaining
standards
on
January
26,
1999,
again
disapproving
some
and
approving
others.
On
March
31,
1999,
American
Wildlands
amended
its
complaint
to
challenge
the
EPA's
approval
of
several
of
Montana's
standards.
The
district
court
affirmed
each
of
the
EPA's
actions.
Am.
Wildlands
v.
Browner,
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
4637&
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Y&
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2000299575>
94
F.
Supp.
2d
1150
(
D.
Colo.
2000)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0
&
DB=
4637&
FindType=
Y&
SerialNum=
2000299575>.
This
appeal
followed.
Specifically,
American
Wildlands
appeals
the
district
court's
conclusion
that:
(
1)
the
EPA
properly
approved
Montana
water
quality
standards
that
exempt
nonpoint
source
pollution
from
antidegradation
review;
and
(
2)
the
EPA
properly
approved
Montana
mixing
zone
policies
and
procedures
exempting
the
areas
within
the
mixing
zone
from
antidegradation
review.

III.
Standard
of
Review
"
Our
standard
of
review
of
the
lower
court's
decision
in
an
APA
case
is
de
novo."
N.
M.
Cattle
Growers
Ass'n
v.
United
States
Fish
&
Wildlife
Serv.,
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
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S&
SerialNum=
2001419877&
ReferencePosition=
1281>
248
F.
3d
1277,
1281
(
10th
Cir.
2001)
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
2001419877&
ReferencePosition=
1281>.
We
will
not
overturn
an
agency
action
unless
it
"
fails
to
meet
statutory,
procedural
or
constitutional
requirements,
or
unless
it
is
arbitrary,
capricious,
an
abuse
of
discretion,
or
otherwise
not
in
accordance
with
law."
Sac
&
Fox
Nation
v.
Norton,
<
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com/
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Default.
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rs=++++
1.0&
vr=
2.0&
DB=
506
&
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S&
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2001180097&
ReferencePosition=
1260>
240
F.
3d
1250,
1260
(
10th
Cir.
2001)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
2001180097&
ReferencePosition=
1260>
(
citing
5
U.
S.
C.
§
706(
2)(
A)­(
D)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000546&
DocName=
5USCAS706&
FindType=
L>).
Specifically,
we
review
the
EPA's
decision
to
approve
state
water
quality
standards
under
the
arbitrary
and
capricious
standard.
City
of
Albuquerque,
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1996226465
&
ReferencePosition=
426>
97
F.
3d
at
426
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1996226465&
ReferencePosition=
426>
(
reviewing
the
EPA's
approval
of
water
quality
standards
proposed
by
an
Indian
tribe
treated
as
a
state
under
the
Clean
Water
Act
under
the
arbitrary
and
capricious
standard);
accord
Natural
Res.
Def.
Council,
Inc.,
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1994048161&
ReferencePosition=
1403>
16
F.
3d
at
1403­
04
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1994048161&
ReferencePosition=
1403>
(
reviewing
the
EPA's
approval
of
state
water
quality
standards
under
the
arbitrary
and
capricious
standard);
Natural
Res.
Def.
Council,
Inc.
v.
Fox,
<
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rs=++++
1.0&
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2.0&
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345
&
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1995243787&
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161>
909
F.
Supp.
153,
161
(
S.
D.
N.
Y.
1995)
<
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www.
westlaw.
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Default.
wl?
rs=++++
1.0&
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345
&
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1995243787&
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161>
(
same).

[
1]
American
Wildlands
argues,
however,
that
due
to
the
unique
approval
role
played
by
the
EPA,
any
approval
decision
by
the
EPA
necessarily
implicates
purely
legal
questions
of
when
water
quality
standards
are
consistent
with
the
Act
which
we
must
review
with
no
deference
to
the
agency.
We
disagree.
In
Chevron,
U.
S.
A.,
Inc.
v.
Natural
Resources
Defense
Council,
Inc.,
<
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www.
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com/
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708&
FindType=
Y&
SerialNum=
1984130736>
467
U.
S.
837,
842­
43,
104
S.
Ct.
2778,
81
L.
Ed.
2d
694
(
1984)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708&
FindType=
Y&
SerialNum=
1984130736>,
the
Supreme
Court
created
a
two­
step
approach
to
judicial
review
of
agency
interpretations
of
acts
of
Congress.
First,
if
a
statute
is
clear
and
unambiguous,
the
language
of
the
statute
controls.
Id.
<
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com/
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Default.
wl?
rs=++++
1.0&
vr=
2.0&
FindType=
Y&
SerialNum=
1984130736>
However,
"
if
the
statute
is
silent
or
ambiguous
with
respect
to
the
specific
issue,"
then
"
the
question
*
1197
for
the
court
is
whether
the
agency's
answer
is
based
on
a
permissible
construction
of
the
statute."
Id.
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708&
FindType=
Y&
SerialNum=
1984130736>
at
843,
104
S.
Ct.
2778.
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708
&
FindType=
Y&
SerialNum=
1984130736>
Before
granting
the
EPA's
approval
determination
Chevron
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
FindType=
Y&
SerialNum=
1984130736>
deference,
however,
we
must
ask
whether
"
Congress
delegated
authority
to
the
agency
generally
[
to
make
such
determinations]
carrying
the
force
of
law,"
and
whether
"
the
agency
interpretation
claiming
deference
was
promulgated
in
the
exercise
of
that
authority."
United
States
v.
Mead
Corp.,
<
http://
www.
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com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
2001518724&
ReferencePosition=
2171>
533
U.
S.
218,
121
S.
Ct.
2164,
2171,
150
L.
Ed.
2d
292
(
2001)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0
&
DB=
708&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
2001518724&
ReferencePosition=
2171>.

It
is
clear
that
Congress
delegated
authority
to
the
EPA
to
make
determinations
as
to
when
water
quality
standards
are
consistent
with
the
Act.
33
U.
S.
C.
§
1313
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0
&
DB=
1000546&
DocName=
33USCAS1313&
FindType=
L>.
As
if
presaging
the
Mead
<
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westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
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Y&
SerialNum=
2001518724>
refinement
of
the
traditional
Chevron
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0
&
FindType=
Y&
SerialNum=
1984130736>
analysis,
this
court
specifically
held
in
City
of
Albuquerque
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
FindType=
Y&
SerialNum=
1996226465>
that
the
EPA
has
been
charged
by
Congress
with
the
authority
to
administer
and
interpret
the
Act.
97
F.
3d
at
422
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1996226465&
ReferencePosition=
422>
("
The
EPA
...
is
entitled
to
considerable
deference
in
its
interpretation
of
the
Clean
Water
Act
because
it
is
charged
with
administering
the
Act");
see
also
Arkansas
v.
Oklahoma,
<
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com/
Find/
Default.
wl?
rs=++++
1.0
&
vr=
2.0&
DB=
708&
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Y&
SerialNum=
1992046720>
503
U.
S.
91,
112,
112
S.
Ct.
1046,
117
L.
Ed.
2d
239
(
1992)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708&
FindType=
Y&
SerialNum=
1992046720>
(
criticizing
this
court
for
failing
to
afford
the
EPA's
interpretation
of
the
Act
"
an
appropriate
level
of
deference");
id.
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708
&
FindType=
Y&
SerialNum=
1992046720>
at
112,
112
S.
Ct.
1046
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
708&
FindType=
Y&
SerialNum=
1992046720>
(
holding
that
Congress
delegated
to
the
EPA
"
substantial
statutory
discretion"
under
the
Act).
Further,
it
is
clear
that
the
EPA's
action
in
this
case
was
taken
in
the
exercise
of
that
authority.
Thus,
the
Mead
<
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westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
FindType=
Y&
SerialNum=
2001518724>
threshold
requirements
are
met.
We
therefore
conduct
a
Chevron
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
FindType=
Y&
SerialNum=
1984130736>
analysis.

The
Act
is
silent
on
the
specific
questions
of
statutory
interpretation
raised
by
this
case.
Thus,
we
will
accord
Chevron
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
FindType=
Y&
SerialNum=
1984130736>
deference
to
the
EPA's
interpretation
of
the
Act
when
it
makes
decisions
to
approve
state
water
quality
standards.
We
therefore
review
the
agency
action
at
issue
here
under
the
arbitrary
and
capricious
standard
and,
in
conjunction,
will
ask
only
whether
the
EPA's
interpretation
of
the
Act
implicit
in
its
action
is
a
permissible
construction
of
the
statute.
"
This
standard
of
review
is
a
narrow
one,
and
we
are
not
empowered
to
substitute
our
judgment
for
that
of
the
EPA."
City
of
Albuquerque,
<
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www.
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com/
Find/
Default.
wl?
rs=++++
1.0
&
vr=
2.0&
DB=
506&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1996226465&
ReferencePosition=
424>
97
F.
3d
at
424
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1996226465&
ReferencePosition=
424>.

IV.
The
EPA's
Approval
of
Montana's
Water
Quality
Standards
A.
Montana's
Standard
Exempting
Nonpoint
Source
Pollution
from
Antidegradation
Review
It
is
the
position
of
American
Wildlands
in
this
case
that
Montana's
Tier
II
antidegradation
policy,
which
does
not
consider
nonpoint
source
pollution,
is
not
consistent
with
the
Act
and
must
be
disapproved
by
the
EPA.
The
EPA
maintains
that
the
Act
does
not
grant
it
authority
to
regulate
nonpoint
sources
of
pollution,
and
therefore,
it
is
powerless
to
disapprove
state
antidegradation
review
policies
on
the
basis
of
how
those
policies
deal
with
nonpoint
source
pollution.

[
2]
The
district
court,
ruling
in
favor
of
the
EPA,
held
that
"
nothing
in
the
CWA
demands
that
a
state
adopt
a
regulatory
system
for
nonpoint
sources."
Am.
Wildlands,
<
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rs=++++
1.0
&
vr=
2.0&
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4637&
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1161>
94
F.
Supp.
2d
at
1161.
<
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www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
4637
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
2000299575&
ReferencePosition=
1161>
We
agree.
In
the
Act,
Congress
has
chosen
not
to
give
the
EPA
the
authority
to
regulate
nonpoint
source
pollution.
See
Kennecott
Copper
Corp.
v.
EPA,
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
350
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1979140029&
ReferencePosition=
1243>
612
F.
2d
1232,
1243
(
10th
Cir.
1979)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
350
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1979140029&
ReferencePosition=
1243>
(
holding
that
the
EPA
lacks
authority
to
regulate
nonpoint
sources
of
pollution);
Appalachian
Power
Co.
v.
Train,
<
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www.
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com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
350
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1976125601&
ReferencePosition=
1373>
545
F.
2d
1351,
1373
(
4th
Cir.
1976)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
350
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1976125601&
ReferencePosition=
1373>
("
Congress
consciously
distinguished
between
point
source
and
nonpoint
source
discharges,
giving
EPA
authority
under
the
[
Clean
Water]
Act
to
regulate
only
the
former.").

*
1198
[
3]
Because
the
Act
nowhere
gives
the
EPA
the
authority
to
regulate
nonpoint
source
discharges,
the
EPA's
determination­­
that
Montana's
water
quality
standards
exempting
nonpoint
source
discharges
from
antidegradation
review
are
consistent
with
the
Act­­
is
a
permissible
construction
of
the
Act.
It
is
true
that
states
are
required
to
"
assure
that
there
shall
be
achieved
...
cost­
effective
and
reasonable
best
management
practices
for
nonpoint
source
control."
40
C.
F.
R.
§
131.12(
a)(
2)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000547
&
DocName=
40CFRS131.12&
FindType=
L>.
It
is
also
true
that
the
standard­
setting
process
in
33
U.
S.
C.
§
1313
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000546&
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33USCAS1313
&
FindType=
L>
applies
generally
to
waters
polluted
by
both
point
source
and
nonpoint
source
pollution.
33
U.
S.
C.
§
1313
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000546&
DocName=
33USCAS1313&
FindType=
L>
(
making
no
distinction
between
pollution
from
point
and
nonpoint
sources).
However,
this
does
not
mean,
as
American
Wildlands
argues,
that
states
are
required
to
regulate
nonpoint
sources
at
the
antidegradation
stage.
Rather,
the
effect
of
nonpoint
source
discharges
on
water
bodies
will
be
diminished
by
state
adoption
of
TMDLs
for
water
bodies
not
meeting
state
water
quality
standards.
Consequently,
we
find
that
the
EPA
did
not
act
arbitrarily
or
misinterpret
the
Act
when
it
approved
Montana's
antidegradation
review
rules.

B.
Montana's
Mixing
Zone
Policies
and
Procedures
[
4]
American
Wildlands
argues
that
Montana's
mixing
zone
policy
allowing
point
source
discharges
to
degrade
water
quality
within
the
mixing
zone
so
long
as
the
discharge
does
not
degrade
the
water
quality
outside
the
zone
is
inconsistent
with
the
Act
because
it
allows
point
source
pollution
to
escape
antidegradation
review
within
certain
areas
of
Montana's
water
bodies.
The
EPA
maintains
that
the
Act's
antidegradation
requirements
apply
to
the
waterbody
as
a
whole,
not
specifically
to
the
mixing
zone.
We
find
the
EPA's
interpretation
of
the
Act
to
be
permissible.

The
use
of
mixing
zones
is
widespread.
Indeed,
the
water
quality
regulations
specifically
allow
for
their
use.
40
C.
F.
R.
§
131.13
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
1000547&
DocName=
40CFRS131.13&
FindType=
L>.
"
Practically
every
state
and
Puerto
Rico
have
adopted
mixing
zone
criteria...."
P.
R.
Sun
Oil
<
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com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
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S&
SerialNum=
1993198848&
ReferencePosition=
75>
Co.
v.
EPA,
<
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www.
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com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
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S&
SerialNum=
1993198848&
ReferencePosition=
75>
8
F.
3d
73,
75
(
1st
Cir.
1993)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1993198848&
ReferencePosition=
75>.
As
noted
above,
mixing
zones
are
allowable
as
a
practical
necessity
because
"[
i]
t
is
not
always
necessary
to
meet
all
water
quality
criteria
within
the
discharge
pipe
to
protect
the
integrity
of
the
water
body
as
a
whole.
Sometimes
it
is
appropriate
to
allow
for
ambient
concentrations
above
the
criteria
in
small
areas
near
outfalls."
Handbook
§
5.1,
at
5­
1.
While
"
the
entire
extent
of
the
water
body
is
not
required
to
be
given
full
existing
use
protection,"
all
effects
"
on
the
existing
use
must
be
limited
to
the
area
of
the
regulatory
mixing
zone."
Id.
§
4.4.4,
at
4­
6.

Moreover,
courts
have
previously
recognized
that
the
reality
of
mixing
zones
makes
measuring
water
quality
standards
at
the
edge
of
the
zone
a
necessity.
P.
R.
Sun
Oil
Co.,
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506&
FindType=
Y&
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S&
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1993198848
&
ReferencePosition=
75>
8
F.
3d
at
75
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
506
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1993198848&
ReferencePosition=
75>
("[
M]
easuring
pollutants
at
the
edge
of
the
mixing
zone
is
widespread
in
the
application
of
the
Clean
Water
Act.");
Marathon
Oil
Co.
v.
EPA,
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
350
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1987126999&
ReferencePosition=
1349>
830
F.
2d
1346,
1349
(
5th
Cir.
1987)
<
http://
www.
westlaw.
com/
Find/
Default.
wl?
rs=++++
1.0&
vr=
2.0&
DB=
350
&
FindType=
Y&
ReferencePositionType=
S&
SerialNum=
1987126999&
ReferencePosition=
1349>
("
By
definition,
the
effluent
itself
[
within
the
mixing
zone]
does
not
meet
water
quality
standards....
It
necessarily
follows,
then,
that
the
edge
or
outer
circumference
of
the
mixing
zone
is
defined
as
the
boundary
at
which
water
quality
standards
are
first
met.").
Finally,
as
mentioned
above,
Montana
has
provided
a
number
of
safeguards
to
ensure
that
mixing
zones
do
not
damage
the
water
quality
of
the
entire
water
body.
Consequently,
we
find
that
the
EPA
did
not
act
arbitrarily
or
misinterpret
the
Act
when
it
approved
Montana's
mixing
zone
policies.

V.
Conclusion
In
sum,
we
hold
that
the
EPA's
approval
of
Montana's
water
quality
standards
was
*
1199
not
done
arbitrarily
or
capriciously.
Furthermore,
the
EPA's
interpretation
of
the
Clean
Water
Act
implicit
in
its
decision
to
approve
those
standards
is
permissible.
[
FN1]
Therefore,
we
AFFIRM.

FN1.
Western
Environmental
Trade
Association's
"
Motion
to
Supplement
the
Administrative
Record,
or,
alternatively,
to
have
Judicial
Notice
taken
of
EPA
Guidance
Document
Excerpts"
is
denied.

260
F.
3d
1192,
52
ERC
2033,
31
Envtl.
L.
Rep.
20,860,
2001
DJCAR
4049
END
OF
DOCUMENT
