E­
1
General
Comments:

Comment:
Object
to
dumping
of
any
chemicals
into
the
ground
or
water
Response:
The
State
of
Oregon
has
established
water
quality
standards
which
are
designed
to
protect
the
beneficial
uses
of
the
water.
Any
actions
taken
by
the
Oregon
Department
of
Environmental
Quality
in
regards
to
the
Columbia
Slough
must
lead
to
the
attainment
of
the
standards.
When
the
standards
are
attained,
human
health
and
aquatic
life
are
protected
from
pollutants
that
may
enter
the
Slough.

Comment:
Appendices
should
be
numbered
distinctly
from
the
main
text,
Table
of
Contents
should
include
the
appendices,
page
numbering
should
be
consistent.
The
document
should
include
a
preface
"
how
to
read
this
document'
and
an
executive
summary
should
be
added.
The
glossary
should
be
expanded.
Cite
references
fully.
Response:
The
document
has
been
revised
to
address
these
comments.

Comment:
Appendices
2
and
3
are
difficult
to
understand,
even
for
technical
readers.
Response:
The
documents
have
been
revised.

Comment:
Inadequate
data
to
assess
sources
and
substantiate
waste
load
allocations.
Toxics
requirements
are
based
on
limited
fish
tissue
data.
Response:
DEQ
disagrees
with
this
comment.
There
have
been
extensive
data
collection
efforts
on
the
Columbia
Slough.
These
efforts
are
extensively
documented
and
are
summarized
below:
 
As
part
of
the
Screening
Level
Risk
Assessment
(
SLRA),
fish
and
crayfish
were
collected
during
the
summer
of
1994
at
10
different
locations
in
the
Columbia
Slough,
and
tested
for
110
different
chemicals.
A
combined
database
of
SLRA
and
historical
fish,
crayfish
and
shellfish
tissue
monitoring
data
contains
sample
results
for
120
chemicals,
with
between
55
and
94
sample
results
available
for
each
chemical.
 
The
City
of
Portland
has
monitored
water
quality
in
the
Lower,
Middle
and
Upper
Columbia
Slough
since
1992.
The
monitoring
has
included
synoptic
and
continuous
monitoring
for
dissolved
oxygen,
pH,
temperature,
biochemical
oxygen
demand
(
BOD),
fecal
coliform,
nitrate,
nitrite,
total
phosphorus,
ortho
phosphate,
turbidity,
TSS,
ammonia
and
chlorophyll
a.
 
Municipalities
have
conducted
storm
water
sampling
as
required
to
apply
for
a
NPDES
storm
water
permit.
Pollutants
measured
included
BOD,
metals,
bacteria,
and
organics.
The
results
of
this
monitoring
are
summarized
in
the
permit
applications
for
the
City
of
Portland,
the
City
of
Gresham
and
the
co­
permittees
(
Portland
MS4
E­
2
NPDES
Municipal
Storm
water
Permit
Application,
Volume
II,
submitted
by
City
of
Portland
and
co­
applicants,
prepared
by
Woodward
Clyde
Consultants,
May
17,
1993;
MS4
NPDES
municipal
storm
water
permit
application,
Part
II,
Submitted
by
City
of
Gresham,
City
of
Fairview,
Multnomah
County,
and
Oregon
Department
of
Transportation,
May
17,
1993).

This
data,
along
with
review
by
DEQ
of
point
source
and
Environmental
Cleanup
Site
records,
allows
for
a
comparison
of
the
relative
loads
of
the
pollutant
sources
and
development
of
an
allocation
strategy.
DEQ
believes
that
this
data
set
is
adequate
to
set
allocations.
Uncertainty
in
the
allocations
is
addressed
by
the
Margin
of
Safety
(
MOS)
and
continuing
monitoring
requirements.

Comment:
The
Total
Maximum
Daily
Loads
(
TMDLs)
do
not
show
that
they
will
lead
to
attainment
of
standards.
Response:
DEQ
has
followed
EPA
guidance
as
described
in
"
Guidance
for
Water
Quality
Based
Decisions:
The
TMDL
Process"
(
EPA
440/
4­
91­
001,
EPA
Office
of
Water,
April
1991).
This
guidance
states
that
a
TMDL
=
Loading
Capacity
(
LC)
=

Waste
Load
Allocations
(
WLAs)
+

Load
Allocations
(
LAs)+
Margin
Of
Safety
(
MOS).
The
TMDLs
developed
for
the
Columbia
Slough
include
an
evaluation
of
the
loading
capacity
of
the
Slough
for
each
parameter.
The
loading
capacity
(
LC)
is
determined
by
the
criterion
times
the
flow,
as
with
Pb,
or
by
modeling,
as
with
dissolved
oxygen.
DEQ
then
developed
an
allocation
strategy
for
each
parameter,
and
assigned
an
allocation
to
each
identified
source.
A
margin
of
safety
(
MOS)
to
account
for
the
uncertainty
about
the
relationship
between
the
pollutant
loads
and
the
quality
of
the
receiving
waterbody
was
developed
for
each
parameter.
Assurance
of
the
implementation
of
controls
is
provided
by
the
issuance
of
an
NPDES
permit,
development
of
a
Memorandum
of
Agreement
or
development
of
an
agricultural
plan.
Additionally,
DEQ
has
outlined
the
requirements
of
Phase
I
and
Phase
II
of
the
Columbia
Slough
TMDL.
These
Phases
include
"
monitoring
requirements
and
a
schedule
for
re­
assessing
TMDL
allocations
to
ensure
attainment
of
water
quality
standards"
(
EPA
1991,
page
15).

Comment:
The
TMDLs
do
not
evaluate
the
most
sensitive
uses.
The
TMDLs
do
not
identify
the
use
of
the
Slough
as
for
subsistence
level
fishing
(
consumption
of
fish
at
higher
than
average
levels,
consumption
of
species
that
have
higher
than
average
levels
of
contamination
due
to
lipid
content,
consumption
of
full
body
rather
than
fillets).
Response:
The
City
of
Portland
conducted
fish
consumption
surveys
in
the
Columbia
Slough
in1994
and
1995.
The
surveys
were
conducted
to:
identify
those
fish
and
shellfish
species
harvested
by
local
anglers,
and
obtain
detailed
information
on
the
fishing
habits,
fish
consumption
preferences
and
fish
preparation
methods
of
the
anglers
(
memo
to
Chee
Choy,
City
of
Portland,
BES,
April
19,
1996,
from
Adolfson
Associates).
From
this
site
specific
information
it
was
determined
that
carp
was
the
most
commonly
caught
fish
in
the
E­
3
Slough.
To
calculate
the
human
health
risk
assessments,
the
site
specific
fish
consumption
rate
was
used
(
from
the
consumption
surveys)
and
consumption
rates
were
calculated
for
the
general
population
and
the
high
use
population.
The
general
population
was
assumed
to
eat
only
fish
fillets
and
the
high
use
population
was
assumed
to
eat
whole
fish
(
Endangerment
Assessment
Report
for
Buffalo
Slough,
Columbia
Slough
Sediment
Remedial
Investigation/
Feasibility
Study,
January
1997,
City
of
Portland
BES).
The
fish
consumption
rates
were
used
to
back
calculate
to
what
concentration
in
fish
tissue
was
necessary
to
meet
the
10­
6
risk
level.
DEQ
and
City
of
Portland
Bureau
of
Environmental
Services
(
under
the
oversight
of
DEQ)
continue
to
work
on
areas
within
the
Columbia
Slough
that
were
identified
in
the
Screening
Level
Risk
Assessment
as
high
priority
sites
(
per
consent
order
DEQ­
ECSR­
93­
09).

Comment:
DEQ
uses
the
terms
criteria
and
water
quality
standards
incorrectly.
Response:
DEQ
has
changed
the
language
within
the
Columbia
Slough
TMDL
to
clarify
that
water
quality
standards
include
three
elements:
designated
uses
for
the
waterbody,
criteria
to
protect
the
designated
uses,
and
an
anti­
degradation
statement
(
EPA
1991,
page
11).

Comment:
The
TMDL
does
not
describe
the
source
of
funding
needed
to
implement
many
of
the
control
strategies.
Response:
NPDES
permit
holders
secure
their
own
funding
to
implement
the
requirements
of
the
permits.
To
implement
the
requirements
of
the
Lower
Willamette
subbasin
plan,
several
sources
of
funding
are
currently
available,
either
through
federal
programs
administered
by
Natural
Resource
Conservation
Service
(
NRCS)
or
a
local
soil
and
water
conservation
district
(
SWCD).
There
are
also
state
cost
sharing
dollars
which
may
be
available
through
the
SWCD
or
through
a
local
watershed
council.
The
state
also
has
funding
under
the
Oregon
Plan
for
Salmon
and
Watersheds
that
landowners,
associations,
or
commodity
groups
can
apply
for
directly.
Finally,
Oregon
is
applying
to
United
States
Department
of
Agriculture
for
additional
funding
under
the
Conservation
Reserve
Enhancement
Program.

Comment:
The
length
of
Phase
I
and
Phase
II
of
the
TMDL
should
be
specified.
Phase
II
should
be
described.
Response:
DEQ
has
included
a
schedule
of
Phase
I
and
Phase
II.
Activities
and
proposed
timelines
are
in
the
schedule.

Comment:
E­
4
Describe
the
requirements
of
the
Willamette
Subbasin
Plan
(
agricultural
sources)
and
include
the
projected
completion
date.
Assurance
that
nonpoint
source
reductions
will
occur
must
be
provided
in
the
TMDL
(
where
both
point
sources
and
non­
point
sources
receive
an
allocation).
Response:
The
Lower
Willamette
Subbasin
Plan
has
a
tentative
completion
date
of
spring
1999
(
Peggy
Vogue,
Oregon
Department
of
Agriculture,
personal
communication,
April
21,
1998).
According
to
Senate
Bill
1010,
the
Oregon
Department
of
Agriculture
may
determine
which
agricultural
lands
are
subject
to
a
water
quality
management
plan
due
to
the
establishment
of
a
TMDL
for
a
body
of
water.
Requirements
for
the
agricultural
water
quality
management
plans
are
described
in
Oregon
Administrative
Rules,
Oregon
Department
of
Agriculture,
Chapter
603,
Division
90.
As
stated
in
OAR
603­
90­
030
the
plans
shall
include
the
following:
 
a
statement
that
the
goal
of
the
plan
is
to
prevent
and
control
water
pollution
from
agricultural
activities
and
soil
erosion
and
achieve
applicable
water
quality
standards
 
a
description
of
the
pollution
prevention
and
control
measures
necessary
to
achieve
the
goal
 
a
schedule
for
implementation
of
the
necessary
measures
 
a
strategy
to
ensure
that
the
necessary
measures
are
implemented
The
plan
is
developed
by
a
local
advisory
committee,
and
will
not
specifically
tell
farmers
what
management
practices
they
have
to
use.
Individual
water
quality
farm
plans
may
be
developed
and
would
contain
practices
and
strategies
the
agricultural
land
owner
can
implement
over
time
in
order
to
address
erosion,
use
of
fertilizer
and
manure,
and
other
issues
that
can
affect
water
quality.

Several
sources
of
funding
are
currently
available,
either
through
federal
programs
administered
by
Natural
Resource
Conservation
Service
(
NRCS)
or
a
local
soil
and
water
conservation
district
(
SWCD).
There
are
also
state
cost
sharing
dollars
which
may
be
available
through
the
SWCD
or
through
a
local
watershed
council.
The
state
also
has
funding
under
the
Oregon
Plan
for
Salmon
and
Watersheds
that
landowners,
associations,
or
commodity
groups
can
apply
for
directly.
Finally,
Oregon
is
applying
to
United
States
Department
of
Agriculture
for
additional
funding
under
the
Conservation
Reserve
Enhancement
Program.

Comment:
An
explanation
of
why
the
flow
rates
used
in
developing
the
loading
capacities
were
chosen
must
be
included.
Response:
The
Columbia
Slough
is
a
managed
system
to
provide
flood
control
for
the
lowlands
surrounding
it.
A
dike
physically
separates
the
Upper
Slough
from
the
Lower
Slough.
Water
flows
through
the
Slough
by
gravity
and
by
periodic
pumping
at
Multnomah
County
Drainage
District
Pump
Station
No.
1
(
MCDD1).
The
flow
rates
of
2.83,
5.66,
8.5
and
11.3
m3/
sec
encompass
the
range
of
flows
possible
by
pumping
at
MCDD1.
A
E­
5
flow
gage
was
installed
in
the
Lower
Slough
in
1989.
According
to
this
gage,
the
range
of
mean
daily
flow
is
from
a
high
of
400
CFS
(
11.3
m3/
sec)
to
a
low
of
about
­
240
CFS
(
the
effect
of
inflows
from
the
Willamette
River).
This
record
is
summarized
in
the
waterbody
assessment
(
CH2MHill,
1995,
Part
2).

Comment:
Air
deposition
should
be
added
to
the
list
of
suspected
sources.
Response:
The
document
has
been
revised
to
reflect
this
comment.

Comment:
All
industrial
permit
holders,
as
well
as
those
that
could
be
permitted,
should
be
accounted
for
in
the
load
allocations.
The
load
from
industrial
sites
is
under­
estimated.
Response:
To
estimate
the
contribution
of
permitted
industrial
storm
water,
DEQ
used
the
simple
method
(
EPA
1992),
using
an
estimate
of
the
area
covered
by
industrial
storm
water
permits.
DEQ
agrees
that
there
are
likely
unpermitted
industrial
sites
that
are
not
accounted
for
in
this
calculation.
The
allocations
were
based
the
relative
contribution
of
permitted
industrial
storm
water
to
the
overall
industrial
storm
water
load.
The
overall
industrial
storm
water
load
was
obtained
from
the
MS4
permit
applications.
These
loads
were
derived
using
an
estimate
of
the
area
within
each
basin
that
fit
the
industrial
land
use
category.
Therefore,
all
industrial
storm
water
sources
were
included
in
the
overall
industrial
load.
Industrial
facilities
that
do
not
have
permits
are
under
the
jurisdiction
of
the
MS4,
until
the
site
is
required
to
apply
for
a
storm
water
permit.
At
that
time,
the
allocation
for
the
newly
permitted
sites
will
be
moved
from
the
MS4
(
DMA,
as
described
in
the
TMDL)
allocation
to
the
permitted
industrial
storm
water
allocation.

Comment:
The
basin
specific
industrial
storm
water
permit
should
be
issued
prior
to
2002
(
expiration
date
of
the
new
permit).
Response:
DEQ
will
develop
and
issue
the
basin
specific
industrial
storm
water
permit
according
to
the
schedule
described
in
Phase
I
of
the
TMDL.
Those
industrial
facilities
within
the
Columbia
Slough
basin
with
storm
water
permits
have
not
been
issued
the
new
1200z
permit.
These
facilities
will
be
required
to
apply
for
the
new
permit
when
it
is
finalized.
DEQ
currently
has
the
permit
on
hold
and
will
initiate
modifications
as
soon
as
the
TMDL
is
approved.

Comment:
DEQ
should
expand
the
list
of
industrial
facilities
that
are
included
under
the
storm
water
industrial
permit.
DEQ
needs
to
state
whether
industries
will
be
required
to
get
a
storm
water
permit
on
the
basis
of
erosion
potential
alone.
TMDL
should
require
BMPs
for
industrial
permittees,
as
it
does
for
DMAs.
Response:
E­
6
DEQ
will
issue
a
basin
specific
general
permit
for
industrial
storm
water.
The
permit
will
be
required
for
those
industries
that
fall
under
the
current
industrial
storm
water
program.
DEQ
will
add
specific
facilities
and
general
categories
of
industries
based
on
information
demonstrating
that
runoff
from
the
sites
is
leading
to
water
quality
impairment.
Such
information
may
include
monitoring
results
from
storm
water
outfalls
and
determination
of
exposure
based
on
site
visits.
Because
some
of
the
pollutants
are
associated
with
sediment
(
organics),
DEQ
will
consider
requiring
permits
for
sites
with
erosion
potential.
Under
the
permit,
DEQ
will
require
BMPs
to
reduce
the
pollutant
contribution
from
storm
water
runoff.

Comment:
All
sources
should
participate
in
required
monitoring.
Response:
All
permitted
sources
will
be
required
to
monitor
for
the
303(
d)
parameters.
The
designated
management
agencies
will
also
be
required
to
monitor,
both
storm
water
effluent
quality
and
instream
water
quality.
The
memorandums
of
agreement
(
MOA)
will
contain
the
specific
monitoring
requirements.
DEQ
is
developing
a
memorandum
of
agreement
with
the
Oregon
Department
of
Agriculture
(
ODA)
to
implement
the
SB
1010
plans.
Any
monitoring
requirements
will
be
described
in
the
MOA
with
ODA.

Comment:
The
document
must
address
the
eutrophication
problem
for
Fairview
Creek
and
Fairview
Lake
to
be
approved
as
a
TMDL
for
these
waters.

A
TMDL
specifically
for
bacteria
in
Fairview
Creek
must
be
developed.

The
TMDL
only
addresses
phosphorus
as
a
pollutant
in
Fairview
Lake.
Sediment
should
be
regulated.
Other
historical
pollutants
should
be
regulated.
Loads
from
Osborn
Creek,
No
Name
Creek
and
Clear
Creek
should
be
regulated.
Response:
Fairview
Lake
and
Fairview
Creek
were
placed
on
the
1994/
1996
303(
d)
list
for
phosphorus
because
they
are
tributaries
to
the
Columbia
Slough.
However,
during
the
summer
months,
when
algal
growth
is
of
concern
in
the
Columbia
Slough,
the
largest
source
of
nutrients
to
the
Slough
is
groundwater,
not
Fairview
Lake
or
Fairview
Creek.
TMDLs
for
Fairview
Creek
and
Fairview
Lake
must
be
developed
which
contain
the
required
components
of
a
TMDL
(
calculation
of
a
loading
capacity,
load
and
waste
load
allocations
and
a
margin
of
safety).
A
TMDL
for
Fairview
Creek
will
be
developed
at
a
later
date
to
address
the
water
quality
limited
status
for
bacteria
(
1994/
1996
303(
d)
list)
and
pH
(
possible
1998
303(
d)
list).
The
cities
of
Gresham,
Fairview,
and
Wood
Village
will
be
required
to
develop
and
implement
management
plans
to
address
pollutants
in
this
TMDL.
Further
efforts
may
be
required
to
address
TMDLs
for
specific
waterbodies
within
the
Columbia
Slough
basin.

DEQ
has
no
data
demonstrating
the
impact
of
other
pollutants
on
water
quality
in
Fairview
Lake
and
Fairview
Creek.
E­
7
Comment:
The
document
incorrectly
refers
to
Oregon
Fresh
Farms
as
Oregon
fresh
Foods
Response:
The
document
has
been
revised
to
reflect
this
comment.

Comment:
Oregon
Fresh
Farms
is
primarily
carrot
packaging,
not
processing
Response:
The
document
has
been
revised
to
reflect
this
comment.

Comment:
Language
in
the
document
should
be
changed
from
"
DEQ
may"
to
"
DEQ
will"
to
avoid
the
impression
of
unfairness
between
the
DMAs
and
DEQ.
Response:
Language
regarding
DEQ
activities
to
implement
the
TMDL
(
e.
g.
development
of
a
basin
general
industrial
storm
water
permit)
has
been
changed
to
read
"
DEQ
will"
and
a
schedule
for
Phase
I
and
Phase
II
activities
has
been
added
to
the
TMDL.

Comment:
References
to
the
Port
of
Portland
or
the
Port
should
be
changed
to
PDX.
Response:
The
document
has
been
revised
to
reflect
this
comment.

Comment:
Storm
water
should
not
be
given
numerical
load
allocations.
Response:
According
to
EPA
guidance
(
EPA
Region
10
TMDL
Review
Framework,
draft,
November
7,
1997),
the
TMDL
must
identify,
to
the
maximum
extent
practicable,
pollutant
sources
that
contribute
to
the
impairment.
Storm
water
has
been
identified
as
a
source
of
many
pollutants
to
the
Slough,
including
bacteria,
Pb
and
pesticides.
DEQ
has
developed
allocations
for
the
identified
sources,
to
meet
the
requirements
of
a
TMDL.
These
allocations
are
expressed
as
a
mass
per
time,
per
EPA
guidance.
Storm
water
permits
will
be
implemented
through
BMPs
rather
than
specific
effluent
limits.
The
MOAs
will
be
used
to
develop
and
implement
strategies
and
monitoring
to
show
the
BMPs
will
achieve
allocations.

Comment:
Multnomah
County
and
DEQ
agreed
to
enter
into
a
Memorandum
of
Agreement
to
implement
the
TMDL.
The
document
should
reflect
this
agreement.
Response:
On
December
24,
1997,
DEQ
issued
a
modification
to
the
NPDES
MS4
permit
for
Multnomah
County.
The
following
statement
was
added
to
Schedule
A,
Condition
2:
"
This
condition
2
of
Schedule
A
to
the
permit
is
not
applicable
to
Multnomah
County".
Schedule
A,
Condition
2
states
that
DEQ
will
be
developing
TMDLs,
including
an
E­
8
implementation
program,
for
several
of
the
receiving
streams
listed
in
the
permit,
including
Columbia
Slough.
Condition
2
also
states
that
DEQ
will
use
memorandums
of
agreement
to
insure
compliance
with
the
storm
water
component
of
the
TMDL
program.
Because
this
condition
is
not
applicable
to
Multnomah
County,
DEQ
will
likely
have
to
enter
into
both
a
memorandum
of
agreement
with
Multnomah
County
and
modify
the
existing
MS4
permit
with
Multnomah
County
to
include
the
necessary
TMDL
components
in
the
permit.

Comment:
The
terms
Waste
Load
Allocation
and
Load
Allocation
are
used
incorrectly.
Storm
water
should
be
given
a
Load
Allocation.
Response:
Storm
water
is
subject
to
a
NPDES
permit,
and
is
a
point
source.
The
document
correctly
refers
to
storm
water
allocations
as
waste
load
allocations.

Comment:
Oregon
Department
of
Transportation
has
no
agreement
with
DEQ
identifying
it
as
a
Designated
management
agency.
Response:
The
Oregon
Department
of
Transportation
has
storm
water
control
responsibilities
as
a
co­
permittee
of
the
City
of
Portland
MS4
permit
and
the
City
of
Gresham
MS4
permit.
According
to
the
MS4
permits,
DEQ
will
enter
into
memorandums
of
agreement
(
MOAs)
with
each
of
the
designated
management
agencies
to
implement
the
TMDL
requirements.
The
MOA
"
will
establish
mutually
agreeable
commitments
for
each
jurisdiction"
(
MS4
permit
No.
101315,
Schedule
A,
2).
DEQ
and
Oregon
Department
of
Transportation
are
currently
developing
a
statewide
MOA.

Comment:
ODOT
can
not
regulate
activities
that
are
outside
of
its
highway
right
of
way.
Response:
DEQ
expects
that
ODOT
will
only
regulate
activities
that
are
within
its
highway
right
of
way.

Comment:
Selected
transportation
BMPs
may
decrease
pollutants
such
as
lead
and
sediments
in
storm
water,
but
may
decrease
dissolved
oxygen
and
increase
temperature.
Response:
DEQ
is
aware
that
BMPs
may
affect
different
water
quality
parameters.
BMPs
or
a
system
of
BMPs
should
be
selected
to
address
the
parameters
addressed
by
the
TMDLs.
There
may
be
a
trade
off
between
pollutants
so
BMPs
should
be
evaluated
and
chosen
on
a
site
specific
basis.
E­
9
Eutrophication
TMDL
Comments
Comment:
Document
should
allow
for
new
discharges
of
phosphate
(
may
or
may
not
use
groundwater
in
processes).
Response:
Modeling
has
indicated
that
new
point
source
wastewater
discharges
will
lead
to
an
increase
in
pH.
New
wastewater
point
sources
are
given
an
allocation
of
zero,
spring
through
fall,
when
the
Columbia
Slough
is
water
quality
limited
because
of
algal
growth.

Comment:
New
discharges
of
groundwater
should
be
allowed.
Groundwater
extraction
operations
should
be
given
a
waste
load
allocation
other
than
zero.
The
groundwater
contribution
of
phosphate
must
be
remediated.
Nutrients
from
local
groundwater
remediation
programs
should
be
regulated.
Response:
Local
groundwater
remediation
programs
may
result
in
the
discharge
of
groundwater
to
the
Columbia
Slough.
Levels
of
total
phosphate
in
the
discharge
are
by
product
of
the
water
source
and
not
added
during
the
remediation
process.
Discharges
of
groundwater
from
remediated
sites
must
meet
an
average
concentration
of
0.12
mg/
L,
which
is
the
predicted
instream
total
phosphate
concentration
in
the
Slough.
The
allocation
for
discharged
groundwater
is
included
in
the
overall
groundwater
allocation.

Comment:
Oregon
Fresh
Farms
does
not
have
data
on
phosphorus
level
in
their
effluent.
Oregon
Fresh
Farms
permit
should
allow
for
a
monitoring
program
over
the
first
permit
term
and
use
the
second
permit
term
for
testing
of
the
new
treatment
system
Response:
DEQ
will
re­
issue
the
permit
for
Oregon
Fresh
Farms
when
the
permit
is
up
for
renewal.
Specific
monitoring
requirements,
including
a
schedule
and
the
parameters
to
be
monitored,
will
be
developed
at
that
time.
The
permit
will
also
include
the
schedule
for
compliance
with
the
waste
load
allocation.

Comment:
The
waste
load
allocation
for
Oregon
Fresh
Farms
should
be
included
as
a
load,
not
a
concentration.
The
use
of
20:
1
dilution
ratio
should
be
explained.
Response:
The
mass
balance
to
estimate
the
effluent
concentration
for
Oregon
Fresh
Farms
was
recalculated
using
flow
measurements
in
Whitaker
Slough
and
measurements
of
flow
from
Oregon
Fresh
Farms.
The
Whitaker
Slough
flow
was
calculated
from
data
provided
by
Bureau
of
Environmental
Services.
There
were
161
values
for
daily
flow
from
July
­
February,
encompassing
the
time
period
when
Oregon
Fresh
Farms
discharges.
The
flow
for
Oregon
Fresh
Farms
was
calculated
as
the
average
of
the
average
flows
recorded
in
E­
10
the
discharge
monitoring
reports.
The
resulting
daily
average
total­
phosphate
load
was
calculated
and
added
to
the
phosphate
allocation
table.

Comment:
It
is
unclear
whether
new
storm
water
outfalls
are
included
in
the
prohibition
of
new
point
source
discharges
of
phosphate.
Response:
The
modeling
described
in
the
TMDL
indicated
that
additional
phosphate
loads
from
waste
water
point
source
discharges
would
cause
an
increase
in
algal
growth
and
an
increase
in
pH.
The
TMDL
has
been
revised
to
clarify
this
result
Comment:
Loads
and
load
allocations
listed
in
Tables
5
and
6
should
be
in
kg/
day.
The
load
allocations
for
phosphate
should
be
in
a
kg/
time
unit.
The
months
covered
by
the
allocation
should
be
stated.
Allocations
for
new
points
sources
and
the
individual
existing
point
source
should
be
included
in
Tables
5
and
6.
In
Tables
5
and
6
industrial
and
municipal
storm
water
should
be
separated.
Response:
The
allocations
are
listed
in
kg/
day
and
the
applicable
time
period
has
been
identified.
Allocations
for
identified
sources
are
included.

Comment:
MCDD
should
not
be
responsible
for
evaluating
the
effect
of
the
macrophytes
on
any
beneficial
uses
except
effects
related
to
its
flood
control
operations.
Response:
The
eutrophication
TMDL
states
"
The
DEQ
will
work
with
MCDD
to
develop
a
management
plan
and
to
document
the
influence
of
the
macrophyte
growth
on
beneficial
uses
of
the
Slough."
DEQ
intends
to
develop
a
management
plan
with
MCDD.
DEQ
will
document
the
influence
of
macrophyte
growth
on
beneficial
uses
with
DEQ
laboratory
staff.
DEQ,
will
however,
require
cooperation
of
MCDD
to
access
sites
for
evaluation.
DEQ
will
develop
the
MOA
with
MCDD
within
six
months
of
EPA
approval
of
the
TMDLs
for
the
Columbia
Slough.

Comment:
There
is
no
MOS
for
nutrients.

The
document
does
not
demonstrate
how
water
level
management
will
result
in
achievement
of
the
water
quality
standards
for
DO,
pH,
chlorophyll
a
and
phosphorus.

The
description
of
eutrophication
modeling
seems
to
contradict
the
assertion
that
water
level
management
will
result
in
the
attainment
of
the
pH
and
DO
criteria.
Explain
The
TMDL
does
not
address
the
contribution
of
particulate
phosphates.
E­
11
If
summer
storm
water
loads
become
more
significant
as
ground
water
loading
decreases,
is
the
affect
significant
enough
to
be
accounted
for
in
the
allocations
and
the
implementation
strategy?
Response:
As
explained
in
the
eutrophication
TMDL,
water
level
management
is
occurring
in
the
Columbia
Slough.
To
demonstrate
the
effect
of
the
management
on
instream
DO
and
pH,
additional
modeling
by
Berger
(
memo
from
Chris
Berger,
Portland
State
University
to
DEQ,
draft
May
15,
1998)
simulated
the
current
load
of
total
phosphate
to
the
Slough.
The
effect
of
nutrient
uptake
by
macrophytes
was
included
in
the
analysis.
Resulting
pH
is
summarized
in
Figure
10
in
the
eutrophication
TMDL.
The
results
predict
that
water
level
management
leads
to
the
attainment
of
the
DO
and
pH
criteria.
This
conclusion
is
supported
by
recent
instream
data
included
in
the
TMDL.

Phosphorus
is
not
a
water
quality
criteria.
Chlorophyll
a
is
an
action
level,
not
a
water
quality
criteria.
If
the
action
level
is
exceeded
the
State
is
required
to
initiate
a
study
to
determine
the
cause
of
the
high
algal
growth.
The
eutrophication
TMDL
addresses
the
cause
of
algal
growth
in
the
Columbia
Slough.
Attainment
of
the
water
quality
standards
is
measured
by
compliance
with
the
DO
and
pH
criteria.

Dissolved
ortho
phosphate
is
the
form
of
phosphate
available
for
algal
growth.
When
algal
growth
was
modeled,
the
transformation
of
organically
bound
phosphate
and
detrital
matter
(
which
are
the
primary
forms
of
particulate
phosphate)
to
dissolved
ortho
phosphate
was
simulated
(
memo
from
Chris
Berger,
Portland
State
University
to
DEQ,
draft
May
15,
1998).

The
effect
of
summer
storm
water
loads
was
also
modeled
and
compared
to
the
base
run,
which
simulates
existing
conditions.
Results
indicate
that
the
effect
of
summer
storm
water
loads
is
minimal,
with
the
predicted
DO
and
pH
meeting
the
criteria.
These
results
are
summarized
in
the
following
table.
Run
1
is
the
base
case.
Run
2
simulated
the
effect
of
summer
storm
water
on
pH
and
DO.
Runs
3
and
4
simulate
the
effect
of
a
50%
and
90%
reduction
in
storm
water
loads
,
respectively.

Run
#
MCDD
Flow
(
CFS)
Total
P
(
mg/
L)
pH
(
max)
DO
(
minimum)
DO
(
7
day
mean,
minimum)
DO
(
30
day
mean
minimum)
1
70
0.12
8.14
7.33
9.44
9.99
2
variable
0.40
8.15
6.01
8.73
9.62
3
variable
0.20
8.15
7.00
9.17
9.83
4
variable
0.04
8.15
7.33
9.58
10.01
The
effect
of
summer
storm
water
on
DO
and
pH
is
not
significant
in
comparison
with
the
base
case
(
Run
1).
Reduction
of
the
storm
water
load
by
50%
and
90%
did
not
affect
the
resulting
pH,
although
the
dissolved
oxygen
did
improve.
EPA
guidance
allows
a
margin
of
safety
to
be
developed
either
by
conservative
modeling
or
by
establishing
a
specific
allocation.
A
margin
of
safety
was
addressed
both
by
conservative
modeling
and
by
setting
aside
remaining
loading
capacity
and
setting
a
zero
E­
12
allocation
for
new
wastewater
point
sources
of
total
phosphate.
The
TMDL
and
MOS
vary
by
flow
and
management
strategy.
These
changes
reflect
the
influence
of
management
strategies
on
the
assimilative
capacity
of
the
Columbia
Slough.
Flow
management
provides
the
advantage
of
greater
assimilative
capacity
as
well
as
providing
a
return
to
more
natural
conditions.
A
TMDL
is
also
presented
for
the
base
case
to
demonstrate
the
greater
nutrient
control
associated
with
lower
assimilative
capacity.

Comment:
The
appropriate
OAR
citation
should
be
included
with
references
to
the
water
quality
standards.
The
language
for
the
pH
criteria
should
be
updated
to
reflect
the
current
regulatory
language.
A
definition
for
"
action
level"
should
be
included.
Response:
The
language
for
the
pH
criteria
has
been
updated.
According
to
OAR
340­
41­
150,
an
average
chlorophyll
a
level
of
15
ug/
L
(
a
minimum
of
three
samples
collected
over
any
consecutive
months)
is
set
to
identify
rivers
where
algae
may
impair
the
beneficial
uses.
This
value
is
not
a
numeric
criteria,
rather
it
triggers
a
requirement
for
DEQ
to
conduct
studies.
When
this
action
level
is
exceeded,
DEQ
will
conduct
studies
to
determine
the
probable
causes
of
the
exceedance
and
develop
a
control
strategy
for
attaining
compliance
with
the
action
level.
Language
defining
an
"
action
level"
has
been
added
to
the
text
of
the
eutrophication
TMDL
and
the
glossary.
The
required
studies
and
control
strategies
have
been
developed.

Comment:
If
nutrients
are
stored
in
the
sediment
they
should
be
accounted
for
in
the
TMDL.
Response:
There
is
no
data
quantifying
the
flux
between
sediment
and
Slough
water
quality.
Sediment
may
act
as
a
sink
for
nutrients
as
well
as
a
source.
There
are
numerous
interactions
that
take
place
in
the
Slough,
(
i.
e.
groundwater
contribution
of
phosphate
and
phosphate
uptake
by
algae)
and
the
effect
of
these
interactions
are
likely
to
have
a
greater
effect
on
Slough
water
quality
than
sediment
loads
during
the
winter
and
subsequent
sediment
flux
in
the
summer.

Comment:
The
TMDL
does
not
account
for
the
impact
of
summer
storm
water
loads.
Necessary
load
reductions
for
storm
water
BMPs
should
be
stated.
Response:
Modeling
by
Wells
(
EWR­
2­
95)
simulated
the
effect
of
various
management
strategies
on
water
quality
in
the
Slough.
The
time
period
simulated
was
August
1
through
September
30,
1992.
The
results
from
this
effort
indicated
that
removal
of
the
storm
water
load
of
ortho­
phosphate
would
lower
the
phosphate
concentration
in
the
Upper
Slough
from
0.07
mg/
L
to
0.06
mg/
L,
while
the
chlorophyll
a
concentration
would
change
from
a
mean
of
54
ug/
L
to
a
mean
of
52.3
ug/
L.
The
effect
of
removal
of
summer
storm
water
loads
was
not
significant.

Comment:
E­
13
The
parameters
to
be
measured
in
Fairview
Lake
and
Fairview
Creek
should
be
specified.
Response:
Water
quality
parameters
will
include
DO,
pH,
temperature,
chlorophyll
a,
dissolved
ortho
phosphate,
total
phosphate
and
bacteria.

Comment:
The
TMDL
should
establish
required
flows
to
lead
to
the
attainment
of
standards.
The
flows
should
be
included
in
the
allocation
tables.
Response:
The
influence
is
more
than
flow
and
depends
on
water
level
management.
MCDD
has
agreed
to
enter
into
a
MOA
with
DEQ
to
maintain
water
level
strategies
in
the
Slough
to
enhance
water
quality.
The
MOA
will
express
the
conditions
needed
to
meet
water
quality
standards.
If
conditions
of
the
MOA
are
not
met,
DEQ
will
re­
assess
the
TMDL
and
the
allocations
to
attain
water
quality
standards
and
take
available
regulatory
actions
needed
to
attain
water
quality
standards.

Comment:
The
TMDL
does
not
adequately
address
the
contributions
of
point
sources
to
the
eutrophication
problem.
Response:
Source
modeling
has
indicated
that
groundwater
is
the
major
source
of
ortho­
phosphate
in
the
summer.
Existing
point
sources
are
mainly
cooling
water
discharges,
and
as
such
have
ortho­
phosphate
levels
that
are
a
byproduct
of
the
water
source.
One
point
source
has
been
identified
as
possibly
contributing
phosphate,
and
has
received
an
allocation
that
will
result
in
no
measurable
increase
in
ortho­
phosphate
levels
instream.
Additional
modeling
has
indicated
that
new
process
wastewater
point
sources
of
phosphate
will
lead
to
increased
pH
and
chlorophyll
a
concentrations,
so
new
wastewater
point
sources
are
given
a
waste
load
allocation
of
zero,
in
the
spring
through
fall.

Dissolved
Oxygen
TMDL
Comments:

Comment:
DEQ
should
describe
how
new
discharges
would
demonstrate
that
adequate
reserve
capacity
exists
to
receive
an
allocation.
Response:
The
allocation
for
future
growth
was
calculated
to
account
for
the
BOD
load
from
the
area
in
the
Slough
drainage
basin
that
is
not
yet
developed
but
will
become
urban.
According
to
the
allocation
modeling,
to
meet
the
urban
storm
water
allocation,
the
average
storm
water
concentration
should
be
about
8
mg/
L
BOD5.
If
the
DMAs
design
the
BMPs
to
achieve
the
target
concentration
of
8
mg/
L,
the
net
load
will
meet
the
reserve
allocation.
If
the
area
under
development
increases
beyond
that
reserved
in
the
future
growth
allocation,
the
concentration
of
the
storm
water
will
have
to
drop
to
meet
the
allocation.
New
industrial
storm
water
point
source
discharges
will
be
required
to
implement
the
BMPs
to
meet
the
BOD5
target
concentration
as
outlined
in
the
storm
water
permit.
E­
14
DEQ
would
determine
if
capacity
exists
in
the
future
growth
allocation
to
allow
new
point
source
(
non
storm
water)
discharges.

Comment:
No
mechanism
for
effluent
trading
is
described.
Response:
A
process
does
not
currently
exist
to
allow
for
effluent
trading.
To
be
effective
any
effluent
trading
process
would
have
to
demonstrate
the
following:
the
loads
traded
were
allocated
loads;
the
trade
would
result
in
no
net
increase
in
BOD
discharge;
and
the
trade
would
continue
indefinitely
(
i.
e.
one
party
would
not
fail
to
meet
the
traded
allocation).

Comment:
The
use
of
the
proportional
reduction
of
BOD
is
not
explained.
The
percent
reduction
equivalent
to
the
relative
contribution
is
unclear.
The
document
appears
to
say
that
3.8
lb.
of
de­
icing
fluid
must
be
removed
for
every
1
lb.
of
urban
storm
water
BOD,
yet
the
allocation
table
(
Table
2)
does
not
reflect
this
ratio.
Response:
EPA
guidance
(
Guidance
for
water
quality
based
decisions:
the
TMDL
process,
EPA
440/
4/­
1/
001)
describes
three
common
methods
for
allocating
loads.
The
first
is
equal
percent
removal,
the
second
method
specifies
equal
effluent
concentrations.
The
third
method
is
a
hybrid
method
in
which
the
criteria
for
waste
reduction
may
not
be
the
same
from
one
source
to
the
next.
A
proportionality
rule
may
be
assigned
that
requires
the
percent
removal
to
be
proportional
to
the
input
source
loading
or
flow
rate.
The
allocations
in
the
TMDL
require
PDX
to
reduce
current
BOD
loads
by
85­
95%
(
based
on
comments
provided
by
PDX).
DEQ
feels
that
it
would
be
inappropriate
to
require
urban
storm
water
to
meet
the
same
percent
reduction,
or
same
effluent
concentration,
as
PDX,
when
the
de­
icing
and
anti­
icing
load
from
PDX
has
been
identified
as
the
primary
cause
of
the
dissolved
oxygen
depletion
during
the
winter
in
the
Columbia
Slough.
DEQ,
therefore,
feels
that
allocations
based
on
the
relative
contributions
of
the
pollutant
is
appropriate
for
a
situation
in
which
one
source
causes
most
of
the
water
quality
impairment.

The
ratio
of
3.8
lb.
of
de­
icing
fluid
to
1
lb.
urban
storm
water
load
reflects
the
decrease
from
current
BOD
loads
to
meet
the
dissolved
oxygen
criteria.
The
ratio
is
based
on
data
from
one
storm
event.
DEQ
recognizes
that
the
ratio
will
vary
by
event.
The
final
allocations
do
not
represent
a
ratio
of
3.8
lb.
of
de­
icing
fluid
to
1
lb.
urban
storm
water,
but
a
relative
reduction
designed
to
be
proportional
to
the
amount
of
BOD
discharged
to
the
Slough.

Comment:
The
document
assumes
that
all
industrial
facilities
requiring
a
storm
water
permit
have
one,
this
is
not
true.
Not
all
discharges
from
permitted
industries
are
through
a
DMA.
Response:
E­
15
The
TMDL
states
that
the
calculations
to
estimate
the
contribution
of
permitted
industrial
storm
water
assumes
that
all
facilities
that
require
a
permit
have
one.
DEQ
realizes
that
there
may
be
many
facilities
within
the
Slough
basin
that
are
unpermitted.
However,
without
an
estimate
of
the
area
covered
by
unpermitted
sites,
there
is
no
method
to
calculate
their
pollutant
contribution.
During
Phase
I
of
the
TMDL,
DEQ
will
work
to
increase
the
number
of
permitted
facilities
in
the
Slough
basin.
Monitoring
data
from
these
sites
will
help
to
refine
the
estimates
of
the
relative
contributions
to
the
pollutant
loads.

Comment:
There
is
no
allocation
for
future
growth
at
the
airport.
Response:
Future
growth
at
the
airport
does
not
receive
a
separate
allocation.
Increased
load
of
BOD,
such
as
that
likely
due
to
the
addition
of
a
runway,
must
be
controlled
by
the
permittee
so
that
the
permit
limits
for
BOD
are
met.

Comment:
The
Port
should
not
be
allowed
to
set
their
own
allocation.
Response:
Allocations
for
PDX
will
be
contained
in
an
NPDES
permit.
PDX
conducted
monitoring
in
the
winter
of
1997/
1998
to
refine
the
estimates
of
the
de­
icing
contribution
to
the
BOD
load
as
well
as
quantify
the
instream
response.
PDX
proposed
to
conduct
additional
modeling,
during
the
course
of
the
permit
term.
DEQ
recognizes
that
the
modeling
may
result
in
changes
to
the
loading
capacity
and
allocations.
All
modeling
would
be
reviewed
by
DEQ
staff.
Allocations
would
still
be
required
to
result
in
compliance
with
water
quality
standards
and
any
changes
to
the
allocations
would
be
in
a
revised
permit.

Comment:
Identification
and
implementation
of
BMPs
(
at
the
Port
of
Portland
to
control
de­
icing
discharge)
should
be
split
into
two
phases.
Response:
PDX
will
implement
structural
and
non­
structural
BMPs
to
meet
the
allocation
for
BOD.
The
selection
and
implementation
of
the
BMPs
may
occur
in
parallel
efforts,
rather
than
sequentially.
Time
frames
for
implementation
of
the
BMPs
will
be
contained
within
the
permit
for
PDX.

Comment:
A
description
of
the
BOD
spreadsheet
model
should
be
included.
Response:
The
document
has
been
revised
to
address
this
comment.

Comment:
The
Portland
State
Model
should
not
be
used
to
develop
the
Port's
allocations.
Response:
E­
16
DEQ
agrees
that
the
model
used
to
develop
the
BOD
allocations
should
be
peer
reviewed.
DEQ
does
not
object
to
the
use
of
another
model
to
simulate
the
instream
response
to
the
BOD
load
estimates.
DEQ
staff
will
review
modeling
results
to
assure
that
final
BOD
allocations
are
in
compliance
with
water
quality
standards.
Should
PDX
fail
to
refine
the
modeling
with
the
additional
monitoring
results,
the
allocations
developed
in
the
TMDL
will
be
PDX's
permit
limits.
These
allocations
were
derived
using
the
spreadsheet
model
described
in
the
TMDL.

Comment:
Re­
aeration
should
be
included
in
the
TMDL
as
a
controllable
variable.
The
Port
should
be
required
to
reduce
the
de­
icing
load
and
take
other
appropriate
measures
to
address
the
DO
issue
in
the
Slough.
Response:
As
stated
in
OAR
340­
41­
445,
the
State
water
quality
standards
require
"
the
highest
and
best
practicable
treatment
and/
or
control
of
wastes,
activities,
and
flows
shall
in
every
case
be
provided
so
as
to
maintain
dissolved
oxygen
and
overall
water
quality
at
the
highest
possible
levels ".
Additionally,
the
water
quality
standards
state
"
Oregon's
water
quality
management
policies
and
programs
recognize
that
Oregon's
water
bodies
have
a
finite
ability
to
assimilate
waste.
Unused
assimilative
capacity
is
an
exceedingly
valuable
resource
that
enhances
in­
stream
values
specifically,
and
environmental
quality
generally"
(
340­
41­
026).
These
regulations
emphasize
the
State's
general
policy
that
waste
must
be
treated
and
instream
treatment
or
use
of
the
receiving
water
body
to
treat
the
waste
is
unacceptable.

Comment:
Flows
of
up
to
11.33
m3/
sec
should
be
included
in
the
allocation
table.
Flows
of
400,
500
and
600
CFS
should
be
included
in
the
allocation
tables.
Response:
The
Columbia
Slough
is
a
managed
system
to
provide
flood
control
for
the
lowlands
surrounding
it.
A
dike
physically
separates
the
Upper
Slough
from
the
Lower
Slough.
Water
flows
through
the
Slough
by
gravity
and
by
periodic
pumping
at
Multnomah
County
Drainage
District
Pump
Station
No.
1
(
MCDD1).
The
flow
rates
of
2.83,
5.66,
8.5
and
11.3
m3/
sec
(
100­
400
CFS)
encompass
the
range
of
flows
possible
by
pumping
at
MCDD1.
A
flow
gage
was
installed
in
the
Lower
Slough
in
1989.
According
to
this
gage,
the
range
of
mean
daily
flow
is
from
a
high
of
400
CFS
(
11.3
m3/
sec)
to
a
low
of
about
240
CFS
(
the
effect
of
inflows
from
the
Willamette
River).
This
record
is
summarized
in
the
waterbody
assessment
(
CH2MHill,
1995,
Part
2).

Comment:
A
loading
allocation
should
not
be
defined
for
the
non
de­
icing
season.
Specify
applicable
months
for
the
BOD
allocations.
Response:
The
DO
TMDL
contains
the
loading
capacity
for
BOD.
The
loading
capacity
section
has
been
revised
to
read
"
The
resulting
load
allocations
are
for
the
winter
months
of
November
through
April.
Allocations
are
not
defined
for
BOD
loads
during
the
summer
E­
17
months."
The
summer
dissolved
oxygen
depletion
(
see
Figure
3)
appear
to
be
the
result
of
stagnant
water
and
algal
processes,
not
BOD
loads,
so
no
BOD
allocations
are
set
for
the
summer
months.

Comment:
The
design
temperature
for
the
BOD
modeling
should
not
be
8
degrees
C.
The
Lower
Slough
DO
is
impacted
by
more
than
de­
icing
discharges.
The
Port's
permit
should
use
a
one
in
five
year
winter
storm
interval.
Response:
Loading
capacity
calculations
and
resulting
allocations
are
for
a
`
reasonable
worst
case'
storm
event.
The
conditions
for
this
event
are
described
in
Appendix
B.
These
conditions
include:
freezing
weather
(
with
de­
icing
occurring)
followed
by
warm
weather
and
increasing
instream
temperatures
and
high
stage
in
the
Willamette
River.
DEQ
acknowledges
that
these
critical
conditions
may
not
be
met
every
time
a
de­
icing
event
occurs.
However,
DEQ
must
develop
permit
limits
that
will
result
in
attainment
of
dissolved
oxygen
criteria
when
the
"
reasonable
worst
case"
storm
event
occurs.

Comment:
The
Port
should
be
not
be
required
to
spend
millions
of
dollars
to
treat
a
discharge
which
occurs
a
few
days
a
year.
The
Port
should
be
allowed
to
address
other
water
quality
problems
instead.
Response:
Permits
must
result
in
the
attainment
of
water
quality
standards.
Water
quality
standards
include:
numeric
and
narrative
criteria,
beneficial
uses
and
anti­
degradation
policy.
EPA's
policy
is
that
of
independent
applicability,
that
is,
all
portions
of
the
water
quality
standards
must
be
attained,
independent
of
each
other.
DEQ
can
not
disregard
the
attainment
of
the
dissolved
oxygen
criteria
in
favor
of
other
water
quality
or
habitat
parameters.

Comment:
Five
years
of
additional
data
should
be
collected
before
the
Port
receives
an
allocation.
The
date
for
model
calibration
should
be
changed
to
October
31,
2000.
The
final
TMDL
should
not
be
set
until
the
winter
of
2000.
Data
should
be
collected
for
at
least
one
more
winter
before
an
allocation
is
set.
Response:
DEQ
has
agreed
to
allow
for
two
additional
years
of
storm
event
monitoring.
Monitoring
will
occur
in
winter
1998/
1999
and
winter
1999/
2000
and
will
include
both
loading
and
instream
sampling.
DEQ
will
require
PDX
to
use
DEQ
approved
quality
assurance/
quality
control
plans.
The
additional
data
will
be
used
to
refine
the
dissolved
oxygen
model
calibration
and
the
loading
capacity.
The
model
calibration,
revised
loading
capacity,
and
allocations
will
be
complete
by
October
2000.

Comment:
Table
3
should
be
referenced
in
the
text.
Figure
6
in
Appendix
B
has
no
title
nor
a
legend
for
the
y­
axis.
Several
other
figures
have
no
titles.
E­
18
Response:
The
document
has
been
revised
to
reflect
this
comment.

Comment:
The
TMDL
discharge
limit
on
PDX
is
extreme.
Response:
DEQ
used
the
best
information
available
to
develop
the
allocations
contained
in
the
DO
TMDL.
The
allocations
were
developed
so
that
the
dissolved
oxygen
criteria
would
be
attained,
even
under
`
reasonable
worst
case'
storm
conditions.
DEQ
acknowledges
that
the
allocation
may
require
substantial
reductions
in
the
BOD
load
from
PDX,
however
such
reductions
are
required
to
attain
compliance
with
the
dissolved
oxygen
criteria.

Comment:
The
TMDL
was
developed
without
adequate
airline
participation.
Response:
PDX
is
responsible
for
the
BOD
load
discharging
from
their
outfalls.
The
allocation
set
in
the
TMDL
is
for
PDX,
not
for
specific
airlines.
DEQ
believes
that
it
is
the
responsibility
of
PDX
to
confer
with
the
airlines
and
any
tenants
at
PDX
to
assure
compliance
with
the
allocation.
Additionally,
DEQ
believes
the
60
day
public
comment
period
provided
adequate
opportunity
for
review
of
the
allocations.
Prior
to
the
issuance
of
any
of
the
permits
to
be
developed
to
implement
the
TMDL
allocations,
there
will
be
an
opportunity
for
additional
comments,
during
the
public
comment
period
for
the
permits.

Comment:
Table
1
and
2
are
inconsistent
in
the
Margin
Of
Safety
(
MOS)
column.
The
MOS
(
beyond
20%)
should
be
allocated
to
the
sources.
Response:
DEQ
agrees
that
the
MOS
varies
from
Table
1
to
Table
2.
This
variation
occurred
due
to
rounding
in
the
calculations
to
allocate
the
loading
capacity
among
the
sources.
The
differences
in
daily
mass
(
kg)
were
allocated
to
the
MOS,
providing
a
greater
assurance
of
compliance
with
the
dissolved
oxygen
criteria.

Comment:
The
Port's
outfalls
discharge
a
combination
of
de­
icing
and
storm
water
discharges.
The
storm
water
contributions
should
be
subtracted
from
the
de­
icing
allocation.
Response:
The
allocation
for
PDX
is
specifically
for
de­
icing
and
anti­
icing
fluid.
Because
PDX
is
also
a
co­
permittee
under
a
MS4
permit,
a
portion
of
the
DMA
allocation
also
is
allocated
to
PDX,
for
its'
non
de­
icing
BOD
load.
According
to
the
allocation
modeling,
to
meet
the
urban
storm
water
allocation,
the
average
storm
water
concentration
should
be
about
8
mg/
L
BOD5.
For
those
outfalls
that
discharge
a
combination
of
storm
water
and
de­
icing
fluid,
the
storm
water
allocation
is
set
at
the
target
BOD5
concentration
of
8
mg/
L
times
the
volume
of
storm
water
flow.
This
allocation
is
then
added
to
the
de­
icing
allocation.

Comment:
E­
19
The
allocation
to
the
Air
National
Guard
is
not
discussed
as
a
permit.
Response:
The
Oregon
Air
National
Guard
(
OANG)
will
be
co­
permittees
and
covered
by
the
PDX
permit.
The
OANG
allocation
is
included
in
Table
2.

Comment:
It
is
not
clear
how
the
20%
MOS
was
developed.
Response:
A
detailed
explanation
of
the
development
of
the
20%
MOS
is
contained
in
Appendix
B.
To
determine
the
MOS
a
range
of
BOD
loading
capacities
were
calculated.
The
loading
capacity
was
calculated
as
the
initial
BOD
that
would
create
a
dissolved
oxygen
deficit
equal
to
the
difference
between
saturation
and
the
dissolved
oxygen
criteria
of
4
mg/
L.
A
range
of
values
for
decay,
aeration
and
theta
(
variation
with
temperature)
were
used
in
these
calculations.
The
20%
margin
of
safety
represents
one
standard
deviation
around
the
average
loading
capacity
calculated.

Comment:
It
is
questionable
that
DEQ
is
requiring
reductions
of
1/
3
to
2/
3
of
current
BOD
levels
for
reaches
4
and
5.
The
allocation
formula
anticipates
a
constant
reduction
in
BOD
loads
from
storm
water.
This
is
unachievable.
Response:
As
explained
in
Appendix
B,
estimates
of
the
current
BOD5
concentration
in
storm
water
range
from
5
mg/
L
to
21
mg/
L.
The
variability
is
due
to
differences
in
event
mean
concentrations
used
and
whether
losses
of
BOD
were
accounted
for.
According
to
DEQ's
model
estimates,
when
the
criteria
are
met
(
after
BMP
implementation)
the
resulting
storm
water
BOD5
concentration
will
average
about
8
mg/
L.
Based
on
these
results,
a
reduction
of
1/
3
to
2/
3
of
the
current
BOD
concentration
is
unlikely.
Monitoring
conducted
in
winter
1997/
1998
will
be
used
to
refine
the
estimates
of
the
BOD
load
(
storm
water
and
de­
icing
fluid)
and
the
resulting
instream
concentration.
The
percent
reduction
targeted
for
storm
water
will
be
better
quantified
at
that
time.

Comment:
It
is
unclear
how
the
expected
150%
increase
in
storm
water
pollutant
loading
relates
to
the
calculation
for
the
allocation
for
future
growth.
Response:
DEQ
interpreted
the
results
of
the
Simplified
Particulate
Transport
Model
(
SIMPTM)
to
mean
that
storm
water
pollutant
loads
would
increase
50%
over
the
current
estimated
loads.
This
is
reflected
in
the
allocation
calculation
that
sets
aside
1/
3
of
the
urban
storm
water
allocation
for
future
growth.

Comment:
Does
future
growth
include
discharges
to
an
MS4
or
only
directly
to
the
Slough?
Response:
E­
20
The
waste
load
allocation
for
future
growth
was
derived
by
setting
aside
1/
3
of
the
total
urban
storm
water
waste
load
allocation.
The
allocation
for
future
growth
includes
discharges
to
an
MS4
as
well
as
discharges
directly
to
the
Slough.

Comment:
Explain
how
the
BOD
levels
from
urban
runoff
do
not
correlate
to
instream
BOD
samples
during
storm
events.
Response:
The
water
quality
models
used
a
mass
balance
to
account
for
the
mass
of
storm
water
BOD
being
added
to
the
Slough
base
flow.
The
storm
water
mass
was
derived
from
the
MS4
monitoring
data.
When
added
to
the
Slough,
the
models
predicted
much
greater
BOD
mass
in
the
Slough
than
observed.
The
discrepancy
between
loads
and
instream
concentration
is
likely
due
to
processes
such
as
deposition
and
decay
during
the
transport
to
the
receiving
water.

Comment:
In
allocation
equations,
the
term
load
allocation
should
be
changed
to
waste
load
allocation.
Response:
The
document
has
been
revised
to
address
this
comment.

Comment:
The
requirements
for
the
DMAs
should
be
included
in
the
MS4
permits.
The
TMDL
must
implement
enforceable
waste
load
allocations
in
the
MS4
permits.
Response:
DEQ
will
enter
into
memorandums
of
agreement
with
each
of
the
designated
management
agencies
that
describe
the
time
frames
and
activities
to
be
completed
to
implement
the
TMDL.
As
stated
in
the
MS4
permits,
"
the
Department
will
utilize
the
MOAs
in
conjunction
with
this
permit
as
the
regulatory
tool
to
insure
compliance
with
the
storm
water
component
of
the
TMDL
program".
Because
the
Multnomah
County
permit
condition
is
different
than
the
other
MS4
permit
it
is
likely
that
both
a
MOA
and
a
modification
to
the
permit
will
be
necessary
to
have
the
appropriate
implementation
framework.

Comment:
The
criteria
used
by
DEQ
are
less
protective
than
those
cited
in
the
regulations.
The
TMDL
does
not
address
whether
the
DO
saturation
standards
will
be
attained.
Response:
The
applicable
dissolved
oxygen
water
quality
criteria
are
the
cool
water
aquatic
life
criteria.
DEQ
has
set
the
allocations
to
attain
the
cool
water
aquatic
life
criteria,
so
the
criteria
have
been
applied
correctly.

Bacteria
TMDL
Comments
Comment:
E­
21
There
is
no
MOS
for
bacteria.
Response:
The
bacteria
TMDL
has
been
revised
to
include
a
MOS
for
bacteria.
The
MOS
is
based
on
an
analysis
of
the
precision
of
bacteria
modeling
and
analysis
of
the
relationship
between
fecal
coliform
data
and
E.
Coli
data.

Comment:
There
is
no
evidence
to
support
the
statement
that
bacteria
prevents
water
contact
recreation
during
fall
through
spring.
Response:
The
fecal
coliform
and
E.
coli
criteria
are
set
to
protect
the
water
contact
recreation
beneficial
use
(
swimming).
Violation
of
the
criteria
indicates
impairment
of
that
use.
The
Columbia
Slough
is
water
quality
limited
for
bacteria
through
all
seasons.

Comment:
What
is
the
frequency
of
exceedance
of
the
bacteria
criteria
in
the
Upper
Slough?
Response:
The
Columbia
Slough
was
designated
as
water
quality
limited
for
bacteria
based
on
data
collected
throughout
the
Slough.
The
16%
exceedance
rate
for
Reach
3,
described
in
the
TMDL,
is
predicted
by
modeling
storm
water
loads
with
SWMM.
An
actual
exceedance
rate
for
Reach
3,
based
on
current
bacteria
data,
was
not
calculated.

Comments:
Numerical
allocations
should
be
given
for
sources.
Response:
DEQ
has
allocated
the
loading
capacity
(
minus
the
margin
of
safety)
to
the
sources.

Comment:
It
should
be
specified
that
monitoring
should
be
for
E.
coli.
Response:
The
implementation
strategy
clearly
states
that
monitoring
in
the
Columbia
Slough
will
be
conducted
to
demonstrate
the
compliance
with
the
E.
coli
criteria.

Comment:
There
is
insufficient
information
to
determine
whether
removal
of
the
CSOs
will
result
in
the
attainment
of
standards.
Response:
As
stated
in
the
Waterbody
Assessment
(
CH2MHill,
1995,)
summer
fecal
concentrations
are
predicted
to
be
less
than
200
coliforms/
100
mL
about
90%
of
the
time
with
the
Columbia
Slough
CSOs
removed.

Comment:
The
CSO
allocation
should
be
the
control
level
approved
by
the
Environmental
Quality
Commission.
Response:
E­
22
According
to
the
Amended
and
Stipulated
Consent
Order
(
WQ­
NWR­
91­
75)
the
City
of
Portland
must
eliminate
all
untreated
CSO
discharges
to
the
Columbia
Slough
from
November
1
through
April
30
except
during
storms
greater
than
or
equal
to
a
storm
with
a
five
year
return
frequency
and
to
eliminate
all
untreated
CSO
discharges
from
May
1
through
October
31
except
during
storms
greater
than
or
equal
to
a
storm
with
a
ten
year
return
frequency.
The
City
of
Portland
must
eliminate
all
untreated
CSO
discharges
to
the
Columbia
Slough,
except
for
the
stated
storm
return
frequencies,
by
no
later
than
December
1,
2000.

Comment:
References
to
removal
of
Willamette
River
CSOs
should
be
removed
from
the
TMDL.
Response:
As
stated
in
the
bacteria
TMDL,
because
the
Lower
Slough
is
tidally
influenced,
it
is
impacted
by
the
presence
of
CSOs
in
the
Willamette
River.
Removal
of
the
Willamette
River
CSOs
will
improve
water
quality
in
the
Lower
Slough.

Comment:
A
TMDL
is
more
than
a
bacteria
management
plan.
Response:
According
to
EPA
guidance
(
EPA
Region
10
TMDL
review
framework,
draft,
November
7,
1997)
specific
components
of
a
TMDL
include
the
following;
a
description
of
applicable
water
quality
standards,
a
loading
capacity,
identification
of
existing
sources,
technical
assessment,
load
allocations
and
waste
load
allocations,
a
margin
of
safety,
and
an
analysis
of
water
quality
attainment
and
public
participation
documentation.
All
of
these
components
are
included
in
the
bacteria
TMDL
that
DEQ
has
developed
for
the
Columbia
Slough.

Comment:
The
TMDL
does
not
assure
that
industrial
storm
water
permittees
will
be
required
to
eliminate
discharges
of
human
waste.
Response:
DEQ
will
develop
a
basin
specific
general
industrial
storm
water
permit
that
will
include
requirements
to
address
the
pollutants
on
the
303(
d)
list.
Requirements
to
detect
and
eliminate
discharges
of
human
waste
will
be
included
in
the
permit.

Comment:
DEQ
has
not
assessed
the
contribution
of
contaminated
groundwater
to
bacteria
levels
in
the
Slough.
Response:
The
transport
of
bacteria
through
soil
is
limited
by
straining
and
sedimentation.
The
soil
acts
as
a
filter
and
as
the
soil
is
disturbed,
the
dispersion
of
soil
particles
strains
even
finer
particles.
Adsorption
also
causes
retention
of
bacteria
by
soil,
but
to
a
lesser
extent.
Because
of
these
factors,
transport
of
bacteria
through
groundwater
is
usually
considered
to
be
unlikely.
DEQ
has
no
data
indicating
any
bacteria
loads
in
groundwater.
E­
23
Pb
TMDL
Comments:
Comment:
Hardness
monitoring
for
industrial
storm
water
discharges
should
be
removed.
Response:
This
requirement
has
been
removed
from
the
TMDL.

Comment:
Page
32,
the
footnote
says
that
non­
detect
values
are
set
at
the
detection
limit
while
page
34
says
that
non­
detect
values
are
set
at
half
the
detection
limit.
The
contradiction
should
be
resolved.
Response:
In
the
frequency
analysis,
the
samples
that
were
non­
detect
values
were
set
at
the
detection
limit
of
0.001
mg/
L.
The
document
has
been
revised
to
address
this
comment.

Comment:
Table
12
(
summary
of
total
lead
loads
to
the
Slough)
underestimates
the
amount
of
lead
sources
because
it
does
not
include
washwater
discharges.
Washing
activities
should
also
be
listed
as
a
source
of
lead
in
Appendix
A.
Response:
The
overall
industrial
storm
water
load
was
obtained
from
the
MS4
permit
applications.
These
loads
were
derived
using
an
estimate
of
the
area
within
each
basin
that
fit
the
industrial
land
use
category.
Therefore,
all
industrial
storm
water
sources
were
included
in
the
overall
industrial
load.
The
industrial
load
estimate
did
not
separate
out
the
various
categories
of
industries
that
would
discharge
storm
water.
The
Pb
allocations
have
been
changed
to
include
an
allocation
for
storm
water
based
on
unit
areas..

Comment:
In
Appendix
A,
page
20,
the
document
should
state
that
generally,
Pb
is
only
detected
in
production
wells
just
after
the
pump
has
been
started
up.
This
may
be
the
result
of
leaching
from
the
pumps.
Response:
Appendix
A,
which
contains
the
source
analyses
for
toxics,
has
been
revised
to
address
this
comment.

Comment:
The
air
deposition
of
Pb
has
not
been
adequately
estimated.
Response:
To
estimate
the
contribution
of
single
source
air
deposition
(
Oregon
Steel
Mill),
DEQ
water
quality
staff
consulted
with
DEQ
air
quality
staff
and
EPA
regional
water
quality
staff.
Calculation
of
the
load
of
a
single
air
source
is
difficult,
with
no
models
readily
available
to
estimate
surface
contribution
from
a
single
air
source.
As
stated
in
Appendix
A,
DEQ
used
EPA
modeling
guidance
to
estimate
the
load
from
the
single
source.
The
estimated
annual
Pb
load
from
Oregon
Steel
Mill
was
comparable
to
that
estimated
by
DEQ
air
quality
staff
for
a
steel
mill
in
McMinnville,
OR.
DEQ
estimated
the
annual
Pb
E­
24
load
from
that
steel
mill
by
measuring
wet
and
dry
deposition.
The
Pb
deposition
estimate
was
within
same
order
of
magnitude
as
that
estimated
for
Oregon
Steel
Mill.

Comment:
It
is
not
clear
how
the
10%
MOS
was
developed.
Response:
The
margin
of
safety
has
been
re­
calculated.
As
stated
in
the
Pb
TMDL,
the
criteria
is
set
as
the
5th
percentile
of
the
criterion
calculated
for
each
sample.
Using
the
5th
percentile
criterion
means
that
95%
of
the
field
samples
should
be
<
0.0012
mg/
L.
The
margin
of
safety
is
set
to
decrease
that
to
0.001
mg/
L
or
the
detection
limit.
This
effectively
means
that
only
5%
of
the
samples
to
be
measured
can
exceed
the
detection
limit.
The
difference
between
the
criterion
of
0.0012
mg/
L
and
the
detection
limit
of
0.001
mg/
L
is
0.0002
mg/
L,
which
is
set
as
the
margin
of
safety.

Comment:
The
calculations
for
the
load
allocations
for
St.
John's
Landfill,
NuWay
Oil
and
sediment
partitioning
are
not
clear.
The
Pb
TMDL
should
address
the
load
from
the
Willamette
River.
Allocations
should
include
the
Willamette
River,
industrial
permittees,
industrial
storm
water
and
environmental
clean
up
sites.
There
should
be
an
allocation
for
future
growth.
Response:
In
May,
June,
August
and
September
1997,
the
City
of
Portland
collected
metals
samples
from
the
Willamette
River.
These
samples
were
analyzed
using
ultra
clean
methods.
Twenty
samples
for
dissolved
Pb
had
a
mean
concentration
of
0.0974
ug/
L
(
data
from
fax
from
Eugene
Lampi,
City
of
Portland,
Bureau
of
Environmental
Services,
May
4,
1998).
The
dissolved
Pb
concentration
in
the
Willamette
River
is,
therefore,
less
than
the
5th
percentile
dissolved
Pb
criterion
(
1.2
ug/
L)
calculated
for
the
Columbia
Slough.

Allocations
have
been
set
for
storm
water
and
environmental
clean
up
sites
on
a
unit
area
basis.
Allocations
for
future
storm
water
or
environmental
clean
up
sites
will
be
deducted
from
the
future
growth
allocation.
These
allocations
are
also
on
a
unit
area
basis.
The
calculations
for
the
allocations
were
re­
written
to
clarify
them.
Estimates
of
flow
and
concentrations
used
in
the
allocation
calculations
are
detailed
in
Appendix
A.

Comment:
There
is
no
need
to
apply
a
5th
percentile
criteria
since
DEQ
calculated
a
criteria
for
each
sample
based
on
hardness.
Response:
The
5th
percentile
represents
a
"
worst
case"
assumption
(
EPA,
1995).
As
stated
in
the
Pb
TMDL,
using
the
5th
percentile
criterion
results
in
a
16.7%
exceedance
rate
of
the
criterion.
When
the
samples
are
compared
to
their
respective
criteria,
the
exceedance
rate
is
10.4%.
Using
either
method,
the
criterion
is
exceeded
at
a
rate
to
designate
the
Columbia
Slough
as
water
quality
limited
for
Pb.
Additionally,
DEQ
needs
to
apply
one
E­
25
criterion
to
calculate
the
loading
capacity
of
the
Slough
for
dissolved
Pb,
so
the
5th
percentile
criterion
was
used.

Comment:
Explain
why
effectiveness
of
BMPs
at
removing
TSS
is
required.
TSS
has
not
been
recommended
as
an
indicator
of
Pb.

The
TMDL
does
not
address
the
accumulation
of
lead
in
sediment
that
will
violate
water
quality
standards.
Response:
DEQ
reviewed
data
from
the
MS4
storm
water
permits.
According
to
this
data,
correlation
between
total
Pb
and
TSS
vary
with
land
use
(
Bob
Baumgartner,
DEQ
personal
communication,
April
1998).
The
particulate
Pb
can
and
will
settle
to
the
sediments.
The
lead
in
sediments
can
partition
to
the
pore
water
and
flux
to
the
surface
water.
If
accumulation
is
great
enough
the
sediments
may
become
toxic.
Lead
may
also
enter
the
food
chain
from
sediments
by
several
mechanisms.
Although
no
sediment
Pb
water
quality
criteria
exist,
DEQ
believes
it
is
appropriate
to
reduce
the
existing
sources.

Comment:
How
can
a
value
be
greater
than
the
criteria
if
it
was
lower
than
the
detection
limit
(
page
37)?
Response:
To
develop
the
table
(
referred
to
in
the
comment),
the
values
measured
instream
were
compared
to
the
detection
limit
and
the
hardness
specific
criteria.
Non
detect
values
were
set
at
the
detection
limit.
The
result
referred
to
in
the
comment
was
for
a
sample
that
was
a
non
detect.
In
the
calculation,
the
criteria
had
more
than
three
significant
figures
and
was
less
than
the
detection
limit.
If
the
criteria
was
rounded
up
to
three
significant
figures,
the
result
would
have
been
that
the
value
was
equal
to
the
detection
limit
and
equal
to
the
criteria.

Comment:
DEQ
should
establish
a
site­
specific
lead
criterion
for
the
Slough,
using
the
water
effects
ratio
(
WER)
method.
Response:
DEQ
used
the
existing
water
quality
standards
to
develop
the
TMDL
for
Pb.
No
information
was
presented
to
suggest
that
a
site
specific
Pb
criteria
is
warranted
to
protect
the
designated
beneficial
uses.
Site
specific
criteria
can
only
be
developed
during
triennial
water
quality
standards
review.
Site
specific
criteria
are
subject
to
EPA
review
and
approval
under
Section
303(
c).

Comment:
A
10%
exceedance
of
the
lead
criteria
is
not
very
large.
Response:
As
stated
in
the
water
quality
standards,
"
Levels
of
toxic
substances
shall
not
exceed
the
criteria
listed
in
Table
20
which
were
based
on
criteria
established
by
EPA..."
DEQ
has
E­
26
stated
that
a
water
quality
standards
violation
occurs
when
"
The
water
quality
standard
listed
in
Table
20
(
see
OAR
341­
41)
for
the
chemical
is
violated
more
than
10%
of
the
time
and
for
a
minimum
of
2
values"
(
Oregon
Listing
Criteria
for
1994/
1996
Section
303(
d)
list,
June
1996).
Waters
that
violate
the
water
quality
standard
are
placed
on
the
303(
d)
list.
The
listing
criteria
and
the
303(
d)
list
are
derived
with
public
review.

Comment:
It
is
improbable
that
lead
is
migrating
in
groundwater
(
page
35).
Response:
Lead
is
not
generally
very
soluble
in
groundwater
at
or
near
neutral
pH.
Lead
has
a
Ushaped
solubility
curve,
and
can
be
mobilized
in
very
acidic
or
very
basic
environments.
Such
conditions
usually
don't
exist
in
groundwater
except
where
spills
or
releases
of
acids
or
bases
have
occurred.
The
lead
at
the
NuWay
Oil
site
is
most
likely
a
component
of
the
used
oil
and
can
be
transported
with
the
oil
to
the
sediments.
Strong
acids
were
used
in
the
oil
re­
refining
process,
and
the
acidic
clay
residue
was
disposed
of
in
a
lagoon
on
the
site.
That
acidic
clay
residue
was
removed
from
the
lagoon
a
few
years
ago
but
the
acid
had
many
years
to
leach
and
mobilize
lead
before
the
removal.
Acidic
conditions
may
still
exist
in
the
groundwater
at
the
site.

The
estimate
of
Pb
migrating
in
groundwater
(
other
than
at
the
NuWay
Oil
site)
was
recalculated
using
½
the
detection
limit
of
the
dissolved
Pb
analysis.
This
calculation
is
a
conservative
estimate
and
the
groundwater
contribution
is
allocated
at
its
current
load.

Comment:
The
relationship
between
modeling
of
storm
water
lead
loads
and
observed
instream
concentrations
is
unclear.
Response:
The
discrepancy
between
loads
and
instream
concentration
is
likely
due
to
processes
such
as
deposition
and
partitioning
during
the
transport
to
the
receiving
water.

Comment:
The
level
of
lead
contamination
in
sediment
is
never
discussed.
Response:
The
sources
document,
Appendix
A,
includes
an
estimate
of
the
annual
load
of
Pb
from
contaminated
sediment.
An
allocation
for
sediment
partitioning
and
diffusive
flux
is
included.

Comment:
DEQ
can
not
use
the
dissolved
criterion
for
lead
until
it
has
been
approved
by
EPA.
Response:
The
water
quality
criterion
is
for
total
Pb.
DEQ
used
a
conversion
factor
developed
by
EPA
to
convert
the
total
Pb
criterion
to
a
dissolved
form.
Because
the
dissolved
criterion
correlates
to
the
total
criterion,
the
loading
capacity
and
the
allocations,
based
on
the
dissolved
form,
will
meet
the
total
Pb
criterion
as
well.
Water
quality
standards
will
be
met
when
the
dissolved
Pb
criterion
is
met.
The
mean
of
the
conversion
factors
is
E­
27
provided
in
the
TMDL
and
the
dissolved
Pb
allocations
can
be
divided
by
it
to
obtain
total
Pb
allocations.

Comment:
There
is
no
assurance
site
specific
information
from
clean
up
sites
will
be
developed
and
used
to
measure
compliance
with
water
quality
standards.
Response:
The
TMDL
for
Pb
and
organics
include
waste
load
allocations
based
on
unit
area
of
storm
water
drainage
basins
and
ECSI
sites.
Waste
load
allocations
can,
therefore,
be
calculated
for
individual
ECSI
sites
as
they
are
identified
and
remediated.
Additionally,
DEQ
water
quality
staff
has
provided
the
clean
up
program
with
language
for
the
"
hot
spot"
guidance
used
by
DEQ
clean
up
staff
to
determine
the
applicable
standards.
Finally
DEQ
water
quality
staff
will
provide
training
for
site
response
and
clean
up
staff
that
describes
a
process
to
determine
if
a
waste
load
allocation
is
necessary
for
a
site
and
the
desired
clean
up
level
necessary
to
meet
water
quality
standards.

Comment:
There
is
no
evaluation
whether
the
loading
capacity
will
result
in
fish
tissue
levels
that
meet
water
quality
standards.
Response:
Table
20
(
in
OAR
340­
41)
includes
criterion
for
the
protection
of
aquatic
life
and
human
health.
The
total
Pb
criterion
for
the
protection
of
aquatic
life
(
chronic
criterion)
is
3.2
ug/
L.
The
total
Pb
criterion
for
protection
of
human
health,
water
and
fish
ingestion,
is
50
ug/
L.
DEQ
has
set
the
allocations
to
meet
a
dissolved
Pb
criterion
based
on
the
total
Pb
criterion.
Because
the
aquatic
life
criterion
is
less
than
the
human
health
criterion,
if
the
aquatic
life
criterion
is
met
the
human
health
criterion
is
met.

Organics
(
DDE,
DDT,
Dioxin)
TMDL
Comments
Comment:
There
is
no
MOS
for
organics.
It
is
unclear
how
the
margin
of
safety
was
established.
The
margin
of
safety
does
not
account
for
the
uncertainty
in
the
analysis
(
use
of
the
annual
average
flow,
lack
of
information
on
sediment
partitioning
for
dioxin).
Response:
The
margin
of
safety
for
organics
is
set
as
½
the
loading
capacity
left
after
the
allocation
for
sediment
partitioning
is
subtracted.
Storm
water
and
sediment
data
collection
efforts
are
continuing
in
the
Slough.
This
information
will
be
used
to
refine
the
modeling
of
the
effect
of
sediment
partitioning
and
storm
water
inputs
on
fish
tissue
concentration.
In
Phase
II
of
the
TMDLs,
DEQ
will
use
the
results
of
the
monitoring
and
modeling
to
refine
the
margin
of
safety
and
the
waste
load
allocations
E­
28
Comment:
Samples
referenced
in
Table
20
were
not
storm
water
samples.
Table
19
should
include
the
frequency
of
detection.
On
page
41,
the
reference
to
Table
13
should
be
Table
20.
Use
consistent
units
in
Tables
19
and
22.
Response:
Tables
20,
21
and
22
summarize
the
results
of
monitoring
conducted
as
part
of
the
Columbia
Slough
Sediment
Remediation
Project.
Sampling
occurred
during
a
dry
event
and
a
storm
event.
The
dry
event
samples
were
collected
in
mid
summer
when
no
storm
water
flows
were
present.
Sample
SW­
3
was
the
only
sample
of
sediment
collected
from
the
storm
water
system.
This
sample
was
collected
from
two
storm
water
catch
basins.
Sediment
samples
SW­
1,
SW­
2,
SW­
4
and
SW­
6
were
collected
in
the
receiving
water.
The
storm
water
samples,
summarized
in
Table
22,
were
collected
in
October
during
a
representative
storm
event.
These
samples
were
storm
water
samples,
collected
at
the
first
manhole
upstream
of
the
outfall
opening.
The
exception
is
the
storm
water
sample
collected
at
SW­
3,
which
was
taken
from
a
catch
basin
above
the
outfall
(
Chris
Prescott,
BES,
personal
communication,
1998).
Table
20
summarizes
the
number
of
samples
and
number
of
detects
from
these
samples.
Because
this
information
is
also
contained
in
Tables
21
and
22,
Table
20
has
been
deleted
from
the
TMDL.
Data
summarizing
the
results
from
sediment
samples
taken
in
the
receiving
waterbody
has
also
been
deleted,
as
these
results
may
not
represent
the
contribution
of
sediment
from
storm
water.
Additional
text
has
been
added
to
clarify
the
sampling
conditions
for
the
storm
water
samples.
Within
the
text,
references
are
made
to
the
appropriate
table
numbers.
The
units
for
Tables
19
and
22
(
now
Table
21)
remain
as
mg/
L
and
ng/
L
as
these
were
the
units
established
for
the
detection
limits.

Comment:
Buffalo
Slough
has
identified
pollutant
sources.
Are
results
from
this
Slough
being
used
as
the
basis
for
requirements
for
all
Reaches?
Are
Buffalo
Slough
results
representative
of
the
rest
of
the
Slough?
Are
the
levels
of
DDT,
DDE,
DDD
and
dieldrin
present
in
these
sediments
a
problem?
Response:
The
screening
level
risk
assessment
(
SLRA)
for
Columbia
Slough
evaluated
and
ranked
300
sediment
sites
on
the
basis
of
relative
hazards
to
human
health,
aquatic
life
and
wildlife.
Buffalo
Slough
was
chosen
for
a
focused
remedial
investigation,
in
part,
because
of
the
potential
to
apply
the
results
to
other
priority
sites,
as
the
conditions
found
in
Buffalo
Slough
are
similar
to
several
of
these
other
sites.
According
to
the
Columbia
Slough
Sediment
Project
(
Focused
Feasibility
Report
for
Buffalo
Slough,
May
1997,
Final
Draft),
several
sites
were
prioritized
on
the
basis
of
detected
or
non
detected
pesticides
or
PCBs
in
sediment.
These
sites
include
Johnson
Lake,
Peninsula
Drainage
Canal,
and
Whitaker
Slough.
Similar
to
Buffalo
Slough,
these
sites
pose
potential
risks
to
human
health
through
consumption
of
fish
tissue
contaminated
with
PCBs.
Additionally,
fish
tissue
PCB
levels
are
comparable
to
those
found
at
the
reference
sites
(
Willow
Bar
Island
Slough
and
Fairview
Creek)
and
are
indicative
of
urban
background
levels
in
the
Portland
area.
For
these
reasons,
results
from
Buffalo
Slough
are
considered
representative
of
the
E­
29
Slough
basin,
and
were
used
to
develop
the
strategy
to
control
organic
loads
into
all
reaches
of
the
Slough.

Comment:
There
are
no
detects
of
PCBs
in
storm
water,
there
is
not
an
adequate
basis
for
a
PCB
TMDL
for
storm
water.
Response:
Results
from
the
Columbia
Slough
Sediment
Project
(
Focused
Feasibility
Report
for
Buffalo
Slough,
May
1997,
Final
Draft)
indicate
that
PCBs
are
carried
into
the
Slough
with
sediment
in
storm
water.
Additional
data
collection
is
occurring
to
verify
this
conclusion.
Monitoring
(
under
the
MS4
permit
and
the
Buffalo
Slough
feasibility
study)
has
also
indicated
that
DDT,
DDD
and
DDE
are
carried
into
the
Slough
with
storm
water
and
DDE
with
storm
water
sediment.
DEQ
has
not
yet
developed
an
empirical
relationship
between
TSS
and
organic
concentrations,
but
a
pilot
project
will
be
conducted
to
determine
the
relationship.
In
Phase
I,
the
TMDL
allocations
are
based
on
storm
water
loads,
but
the
implementation
strategy
focuses
on
the
reduction
of
sediment
loads
to
the
Slough.
Phase
II
of
the
TMDL
may
include
targets
for
%
reduction
of
TSS,
based
on
the
empirical
relationship.

Comment:
There
is
insufficient
data
to
list
dieldrin
as
a
chemical
of
concern.
Response:
DEQ
has
developed
a
preventative
TMDL
for
dieldrin.
As
discussed
in
the
organics
section
of
the
TMDL
document,
dieldrin
has
been
detected
in
39%
of
fish
tissue
samples
analyzed
and
all
of
the
detected
samples
exceeded
the
Table
20
derived
screening
value.

Comment:
Only
one
of
five
samples
of
fish
tissue
had
a
detectable
level
of
dioxin.
A
section
on
data
validation
for
dioxin
should
be
presented.
Dioxin
should
not
be
included
in
this
TMDL
until
the
appropriateness
of
the
303(
d)
listing
for
dioxin
is
resolved.
A
TMDL
for
dioxin
in
storm
water
should
not
be
developed
until
there
is
evidence
that
dioxin
is
present
in
storm
water
or
in
storm
water
sediments.
Table
17
should
include
the
detection
limits.
The
discussion
on
the
congeners
should
clearly
indicate
whether
all
dioxin
congeners
were
analyzed.
The
TMDL
should
explain
EPA's
methodology
for
accounting
for
the
dioxin
congeners.
The
discussion
regarding
dioxin
is
unclear.
Response:
Data
quality
appears
to
be
an
issue
regarding
the
fish
tissue
data
tested
for
dioxin,
which
was
used
to
place
dioxin
on
the
303(
d)
list.
Previously,
the
City
of
Portland
stated
that
the
1987
fish
tissue
data
(
DEQ,
National
Bioaccumulation
Study)
may
have
had
elevated
levels
of
2,3,7,8
TCDD
due
to
interferences
from
PCBs.
Based
on
this
comment,
DEQ
removed
the
1987
fish
tissue
data
from
the
TMDL
document.
However,
DEQ
laboratory
staff
has
stated
that
they
are
unaware
of
such
interference
(
Rick
Gates,
DEQ,
personal
communication,
April
1998).
The
1987
fish
tissue
data
has,
therefore,
been
included
in
the
TMDL.
E­
30
The
appropriate
forum
to
discuss
listing
issues
is
during
development
of
the
303(
d)
list.
DEQ
water
quality
staff
suggests
that
the
commentor
provide
DEQ
with
data
to
de­
list
dioxin,
including
more
recent
fish
tissue
data
indicating
non­
detectable
levels
of
dioxin
in
fish
tissue.
The
Columbia
Slough
TMDLs
are
for
those
parameters
on
the
303(
d)
list,
so
a
TMDL
for
dioxin
has
been
calculated.
Additionally,
DEQ
has
a
criteria
for
2,3,7,8
TCDD
only,
so
the
estimated
levels
of
congeners
is
not
used
to
determine
impairment
of
the
beneficial
use.
For
this
reason,
discussion
of
the
congener
calculations
has
been
removed
from
the
TMDL.

Comment:
Erosion
may
not
be
the
only
source
of
sediments
and
particulates
for
industrial
storm
water
permittees.
Response:
BMPs
for
industrial
storm
water
permittees
will
focus
on
the
reduction
of
TSS
loads
to
the
Columbia
Slough.

Comment:
To
identify
impaired
beneficial
uses,
DEQ
must
determine
what
species
are
caught
in
the
Slough,
age,
size,
etc.
and
how
much
fishing
is
done
in
the
Slough.
Response:
The
City
of
Portland
conducted
fish
consumption
surveys
in
the
Columbia
Slough
in1994
and
1995.
The
surveys
were
conducted
to:
identify
those
fish
and
shellfish
species
harvested
by
local
anglers,
and
obtain
detailed
information
on
the
fishing
habits,
fish
consumption
preferences
and
fish
preparation
methods
of
the
anglers
(
memo
to
Chee
Choy,
City
of
Portland,
BES,
April
19,
1996,
from
Adolfson
Associates).
From
this
site
specific
information
it
was
determined
that
carp
was
the
most
commonly
caught
fish
in
the
Slough.
To
calculate
the
human
health
risk
assessments,
the
site
specific
fish
consumption
rate
was
used
(
from
the
consumption
surveys)
and
a
consumption
rate
was
calculated
for
the
general
population
and
the
high
use
population.
The
general
population
was
assumed
to
eat
only
fish
fillets
and
the
high
use
population
was
assumed
to
eat
whole
fish.
The
fish
consumption
rates
were
used
to
back
calculate
to
what
concentration
in
fish
tissue
was
necessary
to
meet
the
10­
6
risk
level.

Comment:
How
does
the
organic
monitoring
data
indicate
that
there
is
an
unacceptable
risk
level
for
human
health?
Response:
According
to
Oregon
Listing
Criteria
for
1994/
1996
Section
303(
d)
list(
June
1996),
DEQ
uses
fish
or
shellfish
consumption
advisories
issued
by
the
Oregon
State
Health
Division
to
indicate
impairment
of
a
beneficial
use.
In
August
1995,
the
Oregon
State
Health
Division
issued
a
fish
consumption
advisory
that
recommended
limiting
human
consumption
of
fish
caught
in
the
Columbia
Slough
based
on
the
presence
of
PCBs
in
the
fish
tissue.
In
August
1995,
the
Health
Division
concurred
that
DDT/
DDE
should
be
included
in
updates
to
the
fish
advisory.
Additionally,
DEQ
determines
an
impairment
of
the
beneficial
use
E­
31
when
the
chemical
has
been
detected
in
more
than
10%
of
available
fish
tissue
samples,
and
the
mean
of
the
detects
exceeds
a
screening
level
value
derived
from
Table
20
criteria.
In
developing
the
1994/
1996
303(
d)
list
DEQ
determined
that
fish
tissue
data
for
2,3,7,8
TCDD
met
the
listing
criteria.
The
determination
of
impairment
of
the
beneficial
use,
therefore,
is
determined
by
fish
tissue
levels,
not
instream
data
or
source
data.

Comment:
It
has
not
been
shown
that
storm
water
and
sediments
are
a
significant
source
of
pesticides
and
PCBs.
Response:
The
pesticides
and
PCBs
addressed
in
these
TMDLs
are
no
longer
used
and
are
present
in
the
environment
as
a
result
of
past
practices.
As
such,
the
potential
sources
are
limited
(
i.
e.
runoff,
air
deposition).
DEQ
feels
that
the
data
provided
under
the
MS4
permits
and
the
Columbia
Slough
Sediment
Remediation
Project
demonstrate
that
pesticides
are
being
contributed
to
the
Slough
system
via
storm
water.
Based
on
the
dry
weather
sample
taken
at
SW­
3
(
results
summarized
in
Table
20)
DEQ
believes
that
sediment
associated
with
storm
water
is
likely
contributing
PCBs
to
Buffalo
Slough.
Additional
monitoring
is
being
conducted
by
the
City
of
Portland
to
verify
this
conclusion.
In
the
interim,
DEQ
has
followed
EPA
guidance
and
developed
the
TMDL
for
PCBs
and
the
pesticides
based
on
best
available
information.

Comment:
Table
19
should
indicate
whether
the
results
are
for
total
or
dissolved
concentrations.
Response:
Samples
for
organic
analysis
are
typically
not
filtered
because
volatile
organics
might
be
lost
during
the
filtration.
The
samples
collected
for
the
municipal
permits
were
not
filtered,
so
data
presented
in
the
TMDL
is
the
total
organic
concentration
.

Comment:
The
document
states
"
Due
to
the
toxicity
and
bioaccumulation
of
these
materials,
a
low
instream
concentration
causes
fish
tissue
concentrations
to
exceed
consumption
advisory
levels".
This
is
a
general
statement
and
should
not
be
included
in
the
TMDL
document.
DDT
presence
in
the
environment
results
in
very
low
instream
concentrations
that
generally
do
not
cause
fish
tissue
concentrations
to
exceed
advisory
levels.
Pesticides
and
PCBs
are
highly
hydrophobic
and
are
unlikely
to
be
associated
with
storm
water.
The
fugacity
model
assumes
that
sediments
are
in
equilibrium
with
the
overlaying
waters
and
fish
tissue.
It
is
unlikely
that
sediments
are
in
equilibrium
with
fish
tissue
due
to
lack
of
exposure
of
the
fish
to
the
contaminated
sediments.
Response:
These
comments
have
been
grouped
together
because
they
all
address
the
hydrophobicity
of
the
pesticides
and
PCBs
and
their
likely
location
in
the
environment
(
i.
e.
fish
tissue,
instream,
sediment).
The
fugacity
model
was
used
to
determine
in
which
"
compartment"
of
the
environment
the
pollutants
were
most
likely
to
reside.
In
the
fugacity
model
it
is
assumed
that
contaminants
move
from
the
sediments
into
the
water
of
the
Slough
in
two
E­
32
stages.
First,
contaminants
on
the
materials
desorb
from
the
solid
particles
into
the
pore
or
interstitial
water
between
the
sediment
grains.
Then
the
contaminated
interstitial
water
is
fluxed
into
the
Slough
by
groundwater
that
flows
through
the
sediments.
Interstitial
water
concentrations
were
estimated
from
measured
total
sediment
concentrations
and
adjusted
for
the
adsorptive
properties
of
sediment
organic
matter
through
standard
formulas.
The
food
chain
model
has
three
levels:
phytoplankton
(
algae),
zooplankton/
small
fish
and
large
fish
(
carp).
The
initial
input
into
the
food
chain
is
from
the
contaminants
dissolved
in
the
water,
which
are
assumed
to
equilibrate
rapidly
with
the
algae.
The
contaminants
then
biomagnify
to
greater
concentrations
in
the
food
chain.
All
of
the
contaminants
were
assumed
to
accumulate
in
fish
tissues
via
the
food
chain
rather
than
directly
from
the
water.
This
is
an
appropriate
assumption
for
the
compounds
given
their
affinity
for
carbon
rich
materials
and
extremely
low
water
solubility
(
Columbia
Slough
Sediment
Project
Focused
Feasibility
Report
for
Buffalo
Slough,
May
1997,
Final
Draft).
The
fugacity
model,
therefore,
does
not
assume
that
the
fish
are
exposed
to
the
sediments,
rather
that
they
consume
algae
contaminated
with
the
pollutants.
Additionally,
although
the
pollutants
modeled
are
hydrophobic,
they
are
assumed
to
have
some
solubility
in
the
groundwater
which
flows
over
the
contaminated
sediment.
Recent
fugacity
modeling
indicates
that
the
groundwater
flow
rate
is
the
most
sensitive
parameter
in
the
model.

Additionally,
as
stated
in
the
Organics
TMDL,
DEQ
uses
fish
or
shellfish
consumption
advisories
issued
by
the
Oregon
State
Health
Division
to
indicate
impairment
of
a
beneficial
use.
In
August
1995,
the
Oregon
State
Health
Division
issued
a
fish
consumption
advisory
that
recommended
limiting
human
consumption
of
fish
caught
in
the
Columbia
Slough
based
on
the
presence
of
PCBs
in
the
fish
tissue.
In
August
1995,
the
Health
Division
concurred
that
DDT/
DDE
should
be
included
in
updates
to
the
fish
advisory.

Comment:
Groundwater
loading
rates
for
PCBs
should
not
be
based
on
a
single
maximum
concentration.
Response:
Estimates
of
the
groundwater
loads
have
been
revised
to
use
the
average
concentration
of
lead
or
PCBs.
Where
samples
were
measured
at
non
detect
levels,
½
the
detection
limit
was
used
as
the
sample
concentration.

Comment:
ODOT
should
not
manage
pollutants
not
associated
with
transportation
corridors,
such
as
PCBs
and
DDTs.
Response:
In
previous
studies
of
urban
runoff,
PCBs
have
been
detected
in
runoff
from
traffic
corridors
(
U.
S.
Geological
Survey,
Report
96­
4234,
1996).
ODOT
will
be
expected
to
implement
BMPs
to
reduce
possible
loading
of
PCBs
from
traffic
corridors
to
the
Columbia
Slough.
E­
33
Comment:
A
TMDL
must
be
established
for
DDE.
Sources
for
loads,
flows
and
concentrations
should
be
cited.
The
sum
of
the
allocations
must
not
exceed
the
loading
capacity.
Response:
DDE
is
included
in
the
TMDL
for
DDT.
The
flow
rates
of
2.83,
5.66,
8.5
and
11.3
m3/
sec
encompass
the
range
of
flows
possible
by
pumping
at
MCDD1.
Concentrations
used
to
develop
the
allocations
are
discussed
in
Appendix
A.
The
allocations
have
been
re­
calculated
so
that
they
do
not
exceed
the
loading
capacity.

Comment:
Allocations
should
be
assigned
to
industrial
discharges
and
air
deposition.
Response:
PCBs
,
DDT
and
its
metabolites
have
all
been
banned.
There
are
no
industrial
discharges
of
these
pollutants.
The
contribution
of
contamination
from
atmospheric
deposition
is
largely
accounted
for
by
storm
water
because
the
combined
open
surface
area
of
the
storm
water
drainage
basin
is
large
relative
to
the
water
surface
area
of
the
Slough
(
Columbia
Slough
Sediment
Project
Focused
Feasibility
Report
for
Buffalo
Slough,
May
1997,
Final
Draft).
Air
deposition
of
the
organic
pollutants
is,
therefore,
included
in
the
waste
load
allocations
for
storm
water.

Comment:
DEQ
did
not
apply
the
narrative
criterion
for
toxics.
DEQ
must
set
numeric
water
quality
standards
for
sediments.
DEQ
should
use
the
data
and
analysis
of
the
risks
posed
by
Slough
sediments
generated
by
the
Sediment
Remediation
Project.
The
TMDL
does
not
consider
the
additive
and/
or
synergistic
effects
of
multiple
toxic
pollutants.
DEQ
should
not
use
bioconcentration
factors
that
are
chemical
specific
rather
than
species
specific.
Response:
The
allocations
in
the
TMDL
are
based
on
the
current
State
water
quality
standards
and
are
set
with
the
available
data.
The
alternative
to
setting
the
allocations
with
current
information
is
not
to
set
any
allocation,
which
DEQ
does
not
believe
is
appropriate.

Comment:
The
TMDL
does
not
consider
other
existing
uses,
such
as
habitat
for
birds
and
mammals.
The
TMDL
did
not
look
directly
at
the
habitat
of
the
affected
aquatic
life,
which
includes
the
sediments
for
many
of
the
invertebrate
species.
The
TMDL
fails
to
consider
other
designated
and
existing
uses,
such
as
piscivorous
birds
and
mammals
that
may
be
affected
by
toxic
contamination
levels
in
sediments.
Response:
According
to
the
Columbia
Slough
Sediment
Project
(
Focused
Feasibility
Report
for
Buffalo
Slough,
May
1997,
Final
Draft),
the
levels
of
chemicals
in
fish
are
not
high
enough
to
pose
potential
risks
to
wildlife.
Sediment
bioassay
studies
have
indicated
that
sediments
in
Buffalo
Slough
are
not
toxic
to
benthic
organisms.

Comment:
E­
34
The
TMDL
does
not
evaluate
the
contribution
of
sediments
to
fish
tissue
levels
by
direct
consumption
of
bottom
feeders.
Response:
In
the
fugacity
modeling
conducted
to
evaluate
remediation
alternatives
in
the
Buffalo
Slough,
it
was
assumed
that
the
carp
do
not
eat
the
contaminated
sediments,
but
consume
algae.
Standard
ingestion
rates
for
carp
were
used.
The
fugacity
model
is
a
food
chain
model
and
as
such,
allows
for
bioaccumulation
of
the
contaminants
up
the
food
chain.
It
was
therefore
assumed
that
the
algae
would
have
greater
concentrations
of
the
contaminants
than
the
sediment.
If
the
carp
were
assumed
to
be
eating
sediment,
they
would
consume
less
algae
and
therefore
have
less
exposure
to
contaminants
(
Bill
Fish,
Oregon
Graduate
Institute,
personal
communication,
April
1,
1998).

Temperature
Comments
Comment:
The
temperature
management
plan
should
be
developed
through
a
public
process.
Industries
with
100J
permits
or
washwater
activities
should
be
required
to
develop
a
temperature
management
plan.
Implementation
strategies
are
not
provided.
DEQ
expectations
should
be
identified.
A
use
attainability
analysis
has
not
been
done
to
support
the
temperature
criteria.
The
TMDL
relies
on
shading
to
decrease
water
temperature
in
the
Upper
Slough.
Response:
DEQ
will
develop
a
TMDL
for
temperature
at
a
later
date.
E­
35
Hearing
Officer's
Report
A
public
hearing
for
the
Columbia
Slough
Total
Maximum
Daily
Load
(
TMDL)
was
held
February
11,
1998
at
Whitaker
Middle
School,
N.
E.
39,
Portland,
OR.
The
hearing
officer
was
Marilyn
Fonseca,
water
quality
division,
DEQ,
NWR
Summary
of
hearing:
Robert
Baumgartner,
(
Manager
technical
services
section,
water
quality
division,
DEQ,
NWR)
provided
an
overview
of
the
pollution
control
strategies
provided
in
the
TMDL.
Mr.
Baumgartner
also
explained
the
process
for
TMDL
development
and
approval.
The
floor
was
opened
for
a
question
and
answer
session,
but
no
questions
were
asked.

The
formal
hearing
then
began,
with
five
people
providing
oral
testimony.
An
undetermined
number
of
people
will
provide
written
comments.

The
oral
testimony
is
summarized
below
and
the
comments
are
followed
by
DEQ's
response
to
the
testimony.

Comment:
(
Troy
Clark)
Mr.
Clark
was
speaking
for
himself,
not
as
a
representative
of
the
Columbia
Slough
Watershed
Council,
of
which
he
is
a
member.
Mr.
Clark's
primary
concern
is
the
lack
of
consistent
standards
for
TMDLs
on
the
Clean
Water
Act
applied
to
streams
everywhere.
He
is
concerned
that
in
such
a
complex
situation
as
the
Columbia
Slough,
where
problems
appear
to
not
be
resolvable,
allowances
might
be
made
concerning
permits
or
chemicals
or
runoff
introduced
into
the
Slough
which
may
exacerbate
the
problem.
Some
of
the
process
was
motivated
by
a
lawsuit
under
the
Clean
Water
Act.
This
should
be
continuously
on
our
minds
as
we
attempt
to
find
ways
to
resolve
the
problem.
Response:
DEQ
agrees
that
addressing
the
pollution
problems
of
a
complex
system
like
the
Columbia
Slough
is
difficult.
It
is
DEQ's
intention
to
have
the
TMDL
program
be
consistent
with
the
requirements
of
the
Clean
Water
Act.
Any
actions
taken
to
improve
water
quality
in
the
Slough,
such
as
the
issuance
of
permits,
are
designed
to
meet
water
quality
standards.
To
ensure
this,
the
TMDLs
includes
a
margin
of
safety
for
all
the
parameters.
The
margin
of
safety
addresses
the
uncertainty
about
the
relationship
between
the
pollutant
loads
and
the
quality
of
receiving
waterbody.

Comment:
(
Bryan
O.
Wigginton)
Mr.
Wigginton
read
the
Pb
issues
in
the
TMDL.
The
TMDL
states
that
there
is
no
model
of
Pb
transport.
The
TMDL
implies
that
storm
water
running
into
the
Slough
is
not
affecting
the
actual
concentration
in
the
Slough.
The
TMDL
seems
to
say
the
dissolved
lead
concentration
is
80%
of
the
lead
concentration
in
storm
water.
Current
research
indicates
that
the
dissolved
Pb
concentration
is
10­
12%
of
the
lead
concentration
in
storm
water.
The
focus
of
the
TMDL
should
be
suspended
solids
removal.
Total
suspended
solids
removal
would
be
a
good
focus
of
the
TMDL.
Organics
are
also
carried
with
suspended
solids.
E­
36
Response:
Monitoring
under
the
municipal
storm
water
permits
was
for
total
Pb.
Source
analysis
indicates
that
storm
water
is
the
single
largest
source
of
total
Pb
to
the
Slough.
The
loading
capacity
was
calculated
using
dissolved
Pb.
New
monitoring
requirements
for
the
municipalities
and
industries
with
storm
water
permits
will
include
dissolved
and
total
Pb,
as
well
as
TSS.
This
data
will
help
DEQ
better
quantify
the
impact
of
storm
water
on
the
instream
Pb
concentration.
BMPs
will
focus
on
control
of
Pb
in
storm
water,
as
well
as
reduction
of
TSS
contributions.
Management
practices,
will
therefore
address
the
contribution
of
both
dissolved
and
particulate
Pb
to
the
Slough.

Comment:
(
Dana
Siegfried)
Ms.
Siegfried
spoke
as
a
representative
for
the
Port
of
Portland.
TMDLs
were
developed
with
stakeholder
input.
Allocation
for
the
Port
for
de­
icing
fluids
is
very
low
due
to
the
sensitive
nature
of
the
Columbia
Slough.
In
anticipation
of
the
TMDL
the
Port
has
been
working
with
a
stakeholder
group
to
develop
a
long
term
solution
to
de­
icing
runoff
into
the
Slough.
This
group
was
convened
last
September
and
includes
airlines,
DEQ,
the
Bureau
of
Environmental
Services,
neighborhood
representatives,
drainage
districts
and
Portland
State
University.
The
Port
and
the
airlines
will
be
in
a
permit
process
soon
and
will
provide
more
details
on
what
the
long
term
solution
might
be
at
that
time.
Response:
No
response
is
necessary.

Comment:
(
Peggy
McCluskey)
Ms.
McCluskey
is
an
environmental
manager
with
Alaska
Airlines,
but
spoke
as
a
representative
of
all
the
airlines
at
the
Port.
They
are
continuing
to
review
the
TMDL
and
its
impact
on
aircraft
de­
icing
activities
and
expect
to
provide
written
comments
in
March.
The
Federal
Aviation
Administration
strictly
regulates
de­
icing
activities.
Aircraft
must
be
free
of
ice,
snow
and
frost.
Each
airline
performs
de­
icing
in
compliance
with
a
de­
icing
plan
approved
by
the
Federal
Aviation
Administration.
The
proposed
TMDL
will
require
approximately
an
85%
reduction
in
the
amount
of
de­
icing
fluid
entering
the
Columbia
Slough.
The
airlines
have
evaluated
the
de­
icing
processes
to
reduce
discharges
to
the
Columbia
Slough.
They
continue
to
evaluate
and
implement
improvements
to
the
de­
icing
processes.
The
airlines
reaffirm
their
commitment
to
flight
safety
for
passengers,
their
employers
and
the
community.
The
airlines
reaffirm
their
commitment
to
responsible
environmental
stewardship.
Response:
No
response
is
necessary.

Comment:
(
Jay
Mower)
Mr.
Mower
is
the
coordinator
of
the
Columbia
Slough
Watershed
Council
and
spoke
as
the
Council
representative.
The
Council
is
a
diverse
group
of
stakeholders
along
the
Columbia
Slough
including
governments,
neighbors,
businesses,
and
recreational
users.
They
meet
to
coordinate
and
debate
public
policy
about
the
Slough.
There
is
a
subcommittee
preparing
comments
about
the
TMDL.
They
expect
to
submit
the
comments
by
the
March
5
deadline.
The
council
is
praiseworthy
of
the
TMDL.
E­
37
Response:
No
response
is
necessary.
