3M
Specialty
Materials
3M
Center
St.
Paul,
MN
55144­
1000
651
733
1110
31V1
August
1,
2003
VIA
FEDERAL
EXPRESS
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
EPA
East,
Room
6428
1201
Constitution
Avenue,
MW
Washington
DC
20460
Attention:
Docket
No.
AR­
226
and
the
FYI
Docket
Subject:
Submission
ofMonitoring
Data
Pursuant
to
the
3M
LOT
dated
March
13,
2003
and
APFO
Users
LOT
dated
March
14,
2003
Dear
Sir
or
Madam:

This
report
is
submitted
pursuant
to
the
3M
Letter
ofTntent
(
LOT)
dated
March
13,
2003
and
the
APFO
Users
LOT
dated
March
14,
2003.
The
report
is
the
first
submission
under
the
LOIs
ofthe
results
of
groundwater
and
wastewater
monitoring
at
the
3M
manufacturing
sites
at
Cottage
Grove,
MN
and
Decatur,
AL.
As
you
know,
perfiuorooctanoic
acid
(
PFOA)
was
previouslyproduced
at
these
sites..
In
addition,
use
ofPFOA
is
continuing
at
the
Decatur
site,
as
part
ofthe
Dyneon
fluoropolymer
manufacturing
operation.

As
noted
in
the
3M
LOl,
monitoring
ofwastewater
treatment
plant
effluent
and
groundwater
for
the
presence
ofPFOA
has
been
underway
at
the
Decatur
and
Cottage
Grove
sites
for
a
number
of
years.
This
monitoring
was
initiated
as
a
result
of3M
voluntary
commitments
andlor
plans
established
through
permits
with
local
regulators.
Under
the
3M
LOT,
3M
agreed
to
continue
this
monitoring
in
order
to
assess
the
trends
that
are
likely
to
occur
as
a
result
of
the
3Mproduction
phase­
out
of
PFOA,
completed
at
the
end
of2002.
The
Decatur
monitoring
program
was
continued
for
the
additional
purpose
of
assessing
the
impact
ofDyneon'
s
ongoing
use
of
APFO
in
fluoropolymer
manufacturing
activities
at
the
site
and,
in
this
manner,
meeting
Dyneon's
monitoring
commitments
under
the
APFO
Users
LOT.
Because
the
Dyneon
and
former
3M
manufacturing
operations
are
located
at
the
same
site,
it
was
determined
that
monitoring
would
be
conducted
and
reportedjointly
by
3M
and
Dyneon.

In
our
May
7,
2003
letter
to
Ward
Penberthy
of
EPA,
we
provided
a
detailed
description
ofthe
test
methodology,
sampling
plans
and
proposed
test
schedule
for
future
wastewater
and
groundwater
monitoring
at
the
Cottage
Grove
and
Decatur
sites.
Please
note
that
previous
monitoring
at
these
sites
differed
in
some
respects
from
the
future
program
outlined
in
our
May
7
le~~
ter.
These
differences
are
discussed
below
in
the
course
of
reviewing
the
results
of
monitoring
conducted
prior
to
the
LOIs
and
in
mid­
2003.
Background
analytical
reports
for
the
monitoring
are
voluminous
and
are
available
from
3M
on
request.
Page
2
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
As
noted
in
our
LOT,
3M
has
previously
conducted
monitoring
forPFOA
in
surface
water,
sediments
and
fish
in
the
vicinity
of
the
Decatur
site.
The
latest
results
of
this
monitoring,
carried
out
in
2002,
were
submitted
on
July
9,
2003
to
the
OPPTS
AR­
226
Docket
as
part
ofthe
ongoing
3M
investigation
ofperfluorochemistry.
As
described
in
our
May7
letter,
3M
will
update
these
monitoring
results
in
2004
and
2006.

It
should
also
be
noted
that
under
the
APFO
Users
LOT,
Dyneon
is
conducting
air
dispersion
modeling
for
its
Decatur
operations.
Dyneon
will
submit
this
infonnation
to
EPA
by
January
T,
2004.

COTTAGE
GROVE,
MN
SITE
MONITORING
DATA
The
3M
Cottage
Grove
facility
(
the
site)
occupies
approximately
865
acres
ofproperty
in
Cottage
Grove
Minnesota.
The
site
is
bounded
by
open
space
and
farmland
on
the
north,
the
Mississippi
River
on
the
south,
a
municipal
wastewater
treatment
plant
on
the
west
and
sparsely
populated
open
space
to
the
east.
Manufacturing
operationsbegan
at
the
site
in
1947
and
existing
records
indicate
that
PFOA
production
began
about
1976.

Site
Setting
and
Hydrogeology
The
site
is
located
on
a
flat
to
gently
undulating
bluff
overlooking
the
main
channel
ofthe
Mississippi
River.
Both
the
southeast
and
southwest
sides
of
the
sitehave
been
steeply
incised
by
stream
activities.
The
site
is
underlain
by
glacio­~
fluvialdeposits
which
increase
in
thickness
from
north
to
south
across
the
site.
These
deposits
are
underlain
by
the
Prairie
Du
Chein
Group
and
the
Jordan
Sandstone
FormatiOn.
The
St.
Lawrence
Shale
Formation
(
a
confining
layer)
is
present
at
the
base
ofthe
Jordan
Formation,
approximately
200
feet
below
the
central
portion
of
the
site.

Six
high­
capacity
pumping
wells
supply
water
to
the
manufacturing
operations
at
the
site.
The
groundwater
from
four
ofthese
wells
is
blended
in
a
water
supply
distribution
system
on
a
continuous
basis
for
various
site
needs
including
production,
sanitation,
and
limited
potable
use.
Bottled
water
has
been
provided
for
a
number
ofyears
at
the
site
for
thinking
water.
The
remaining
two
wells
are
utilized
independently
on
a
periodic
basis
for
site­
wide
fire
protection
and
non­
contact
cooling
at
the
site
incinerator.
These
six
high­
capacity
wells
were
installed
during
the
period
1947
to
1970.
Four
ofthe
wells
are
drilled
into
the
Jordan
Formation
and
two
ofthe
wells
are
located
in
unconsolidated
alluvium
near
the
Mississippi
River.
However,
all
pumping
wells
obtain
groundwater
from
the
surficial,
unconfined
aquifer.
Although
historical
water
level
data
indicates
a
natural
hydraulic
gradient
toward
the
river,
pumping
of
the
wells
(
which
started
in
1947)
has
created
a
persistent
cone
ofdepression
in
the
ground
water
beneath
the
developed
portions
of
the
site.
The
cone
of
depression
effectively
limits
movement
of
ground
water
from
the
site
to
the
adjacent
river.
All
groundwater
used
for
the
production
processes
is
treated
after
use
at
the
site
wastewater
treatment
facility
prior
to
NPDES
permitted
discharge
to
the
Mississippi
River.
Page
3
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
Monitoring
Results
Groundwater
Monitoring
Starting
in
2001,
3M
conducted
groundwater
monitoring
for
fluorochemicals
as
part
of
a
more
extensive
investigation
carried
out
in
conjunction
with
the
State
of
Minnesota.
This
additional
monitoring
was
initiated
to
assess
the
impact
of
fluorochemical
production
on
the
groundwater
beneath
the
site.
Initially,
monitoring
was
carried
out
at
five
of
the
production
wells
and
a
number
ofmonitoring
wells.
Based
on
understanding
of
the
hydrogeology
and
the
results
of2001
and
2002
sampling,
3M
reyiewed
the
scope
of
groundwater
monitoring
to
be
conducted
under
the
LOT.
The
revised
monitoring
program
adopted
by
3M
is
described
in
our
May
7
letter
to
EPA.
As
explained
in
that
letter,
3M
selected
five
ground
water
sampling
locations
for
semi­
annual
PFOA
monitoring
on
a
going­
forward
basis.
The
five
monitoring
points
were
chosen
as
representative
of
the
following
site
conditions
(
See
attached
site
map):

Monitoring
Point
Site
Condition
MW­
7
Upgradient
ofsite
industrial
activities
MW­
4
Central
to
site
industrial
activities
PZ­
14
Westernldowngradient
ofsite
industrial
activities
MW­
101
Easternldowngradient
ofsite
industrial
activities
Water
supply
distribution
system
Site­
wide
ground
water
from
the
production
wells
PZ,
plezometer,
a
small
monitoring
well
Sampling
ofthe
water
supply
distribution
system
was
substituted
for
sampling
ofthe
individual
high­
capacity
pumping
wells
because
the
water
that
supplies
this
system
is
a
composite
ofwater
drawn
from
these
wells
and
therefore
is
representative
ofgroundwater
throughout
the
developed
portion
of
the
site.
Page
4
Document
Control
Office
(
DCO)
Office
of
Pollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
PFOA
data
from
the
five
monitoring
points
listed
above
was
collected
on
June
5,
2003.
The
results
ofthe
2003
and
previous
sampling
events
for
these
points
are
presented
in
the
table
below.

3M
Cottage
Grove
PFOA
Data
Summary
Date
Sampled
Identification
PFOA
(
ppb)
PFOALab
DS
(
ppb)
PFOA
Field
DS
(
ppb)
PFOA
Avg.
(
ppb)
IStd.
Deviation
~
(+
1­)
07/
11/
01
NA
NA
NA
NA
NC
09/
07/
01
NA
NA
NA
NA
NC
10/
31/
01
NA
NA
NA
NA
NC
11/
12/
01
NA
NA
NA
NA
NC
12/
03/
02
NA
NA
NA
NA
NC
06/
05/
03
0.309
0.307
0.326
0.314
0.01
07/
11/
01
09/
07/
01
10/
31/
01
11/
12/
01
12/
03/
02
06/
05/
03
NA
NA
NA
NA
NC
NA
NA
NA
NA
NC
NA
NA
NA
NA
NC
NA
NA
NA
NA
NC
170
180
172
174
5.29
135
149
125
136
12.06
07/
11/
01
09/
07/
01
Distribution
10/
31/
01
11/
12/
01
12/
03/
02
06/
05/
03
1.23
1.14
NA
1.185
0.06
NA
NA
NA
NA
NC
40.6
38.5
41.1
40.1
1.38
11.4
10.8
17.1
13.1
3.48
NA
NA
NA
NA
NC
28.0
28.1
27.7
27.9
0.21
.07/
11/
01
NA
NA
NA
NA
NC
09/
07/
01
6.40
6.77
6.06
6.41
0.36
10/
31/
01
5.89
4.96
5.25
5.37
0.48
11/
12/
01
4.66
4.63
4.60
4.63
0.03
12/
03/
02
NA
NA
NA
NA
NC
06/
05/
03
4.80
4.67
4.96
4.81
0.15
07/
11/
01
09/
07/
01
10/
31/
01
11/
12/
01
12/
03/
02
06/
05/
03
NA
NA
NA
NA
NC
NA
NA
NA
NA
NC
5.67
5.93
7.39
6.33
0.93
5.30
5.11
5.45
5.29
0.17
NA
NA
NA
NA
NC
10.2
10.2
10.1
10.2
0.06
Table
Notes:

ppb:
Parts
per
billion
NA:
Data
not
available
for
sampling
period
°
NC:
Not
calculated
Field
DS:
Field
duplicate
sample
Lab
DS:
Laboratory
duplicate
sample
Page
5
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
Results
of
groundwater
monitoring
for
sampling
locations
that
were
tested
in
previous
years
but
not
in
2003
are
summarized
in
the
Table
attached
to
this
report.
The
results
presented
above
and
in
the
attached
Table
indicate
that
groundwater
levels
of
PFOA
have
remained
relatively
constant
from
2001
to
2003,
notwithstanding
the
recent
cessation
of
PFOA
production
at
the
site.

Please
note
that,
during
all
groundwater
monitoring
at
this
site,
3M
has
collected
a
field
duplicate
sample
to
provide
a
measure
of
the
precision
associated
with
sample
collection,
preservation
and
storage
as
well
as
laboratory
procedures.
The
laboratory
duplicate
sample
is
taken
in
the
laboratory
and
provides
a
measure
ofthe
precision
associated
with
laboratory
procedures,
but
not
with
sample
collection,
preservation
or
storage
procedures.

As
described
in
the
May
7
letter,
monitoring
points
sampled
in
June
2003
will
be
sampled
again
in
September
2003
and
May2004
and
a
summary
report
of
that
data
will
be
provided
on
August
1,
2004.

Effluent
Monitoring
The
site
has
a
multi­
phased
wastewater
treatment
plant
that
is
used
to
treat
all
process
wastewaters
generated
at
Cottage
Grove.
Two
ofthe
systems
treat
inorganic
wastewaters
and
the
third
is
an
organic,
biological
treatment
system.
All
of
the
treated
process
wastewaters
from
these
operations
are
combined
at
a
single
discharge
point.
These
wastewaters
are
then
combined
with
non­
contact
cooling
and
storm
water
and
then
discharged
to
the
Mississippi
River.

Since
January
2000,
the
3M
Cottage
Grove
plant
has
conducted
PFOA
analysis
of
its
effluent.
Sampling
has
been
performed
monthly
beginning
in
January
2003
in
accordance
with
the
requirements
of
3M's
NPDES
permit.
This
information
is
reported
to
the
Minnesota
Pollution
Control
Agency
in
the
monthly
Discharge
Monitoring
Reports
(
DMR).
Effluent
wastewater
samples
are
collected
at
the
plant
outfall
on
the
Mississippi
River.
This
is
the
common
discharge
point
for
all
ofthe
plant's
process
wastewaters.
All
samples
are
collected
as
24­
hour
composites
and
duplicate
analysis
is
conducted
for
each
sample.
Page
6
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
The
following
table
presents
the
monitoring
results
of
the
Cottage
Grove
process
wastewater
effluent
discharged
under
Minnesota
NPDES
Permit
No.
MN000149,
Outfall
SD
001.
The
data
includes
results
of
all
monitoring
events
in
2003
and
in
previous
years.

3M
Cottage
Grove
Effluent
Monitoring
Results
°
PFOA
Analysis
from
SD
001
Sample
Date
PFOA
(
ppb)

I
Januaiy­
March
2000
Average
of
8
.

Data
Points
1991
September­
October
2000
1
Average
of
3
Points
216
December2002
12/
12/
02
180
January
2003
1/
15/
03
°
80.1
77.9
79.0
January
2003
January
2003
Average
February
2003
2/
12/
03
80.0
78.8
February
2003
February
2003
Average
March
2003
3/
12/
03
79.4
74.3
74.7
March2003
~`
Iarch2003
Average
April2003
4/
23/
03
74.5
112.0
109.0
April2003
kpril
2003
Average
May2003
5/
15/
03
110.5
95.0
101.0
May2003
May
2003
Average
1
June
2003
6/
11/
03
.
980
°
18.9
June2003
16.4
June2003Average
~
177
As
shown
above,
PFOA
levels
dropped
substantially
from
2000
to
2003.
Monthly
PFOA
levels
remained
fairly
constant
throughout
the
first
half
of2003
with
a
substantial
decrease
noted
in
June.
Data
obtained
in
future
months
will
enable
us
to
determine
whether
effluent
concentrations
will
remain
at
this
low
level
and
therefore
have
declined
as
a
result
of
the
production
phase­
out.
Page
7
Document
Control
Office
(
DCO)
Office
of
Pollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
The
expected
in­
stream
concentration
of
PFOA
in
the
Mississippi
River
resulting
from
wastewater
discharges
would
be
extremely
low.
Assuming
an
average
base
flow
for
the
Mississippi
River
of
7500
MGD
(
million
gallons
a
day)
and
an
effluent
flow
of
about
3
MGD,
the
expected
in­
stream
PFOA
concentration
would
be
about
30
ppt
(
parts
per
trillion),
very
near
the
detection
limit
of
PFOA.

DECATUR,
AL
SITE
MONITORING
DATA
The
3M
Decatur
site
is
approximately
900
acres
with
the
area
of
the
manufacturing
facilities
being
approximately
200
acres.
The
current
Dyneon
fluoropolymer
production
facilities
are
co­
located
with
3M's
other
manufacturing
operations
at
the
site
where
3M
previously
produced
PFOA
and
other
fluorochemicals.
The
land
surrounding
the
site
is
predominantly
industrial
and
commercial.
Chemical
manufacturing
operations
began
at
the
site
in
1961.
In
1962
the
facility
was
expanded
to
include
a
film
manufacturing
plant.
Production
of
PFOA
at
the
site
occurred
in
1999­­
2000.

Site
Setting
and
Hydrogeology
The
geology
beneath
the
3M
Decatur
site
consists
of
a
dense
residuum
underlain
by
limestone
(
bedrock),
which,
in
turn,
is
underlain
by
a
chert
(
hard
rock)
layer.
The
limestone
underlies
the
residuum
to
an
approximate
depth
of
150
feet
below
ground
surface.
The
number,
extent,
orientation,
and
interconnection
of
water­
bearing
fractures
control
groundwater
flow
associated
with
this
system.
Water­
bearing
fractures
observed
in
this
unit
are
not
continuous,
and
do
not
yield
significant
quantities
of
water.
An
asphaltic
limestone
approximately
10
feet
thick
occurs
below
the
upper
limestone
layer,
and
acts
as
a
lower
confining
unit
for
the
limestone.

The
aquifer
below
the
3M
facility
and
the
City
of
Decatur
is
not
used
as
a
water
supply.
Potable
water
used
at
the
site,
and
the
Decatur
area
in
general,
is
provided
by
the
Decatur
municipal
water
system
whose
source
is
the
Tennessee
River.
Samples
of
the
Decatur
drinking
water
taken
as
part
of
the
3M
Six
Cities
Study
failed
to
detect
the
presence
of
PFOA
at
a
detection
limit
of
7.5
ppt
(
parts
per
trillion).

Because
of
the
presence
of
other
contaminants,
3M
has
undertaken
extensive
studies
to
characterize
the
groundwater
below
the
Decatur
site
and
related
hydrogeology.
Copies
of
these
studies
are
available
on
request.
Potentiometric
data
for
the
site
indicate
that
groundwater
occurs
both
as
unconfined
and
semiconfined
systems.
Unconfined
groundwater
occurs
within
the
residuum,
epikarst,
and
to
some
extent,
shallow
fractures
within
the
limestone.
Groundwater
flow
is
generally
to
the
north
and
east
toward
the
Tennessee
River.
Groundwater
flow
rates
in
the
residuum
and
limestone
are
extremely
slow
and
wells
installed
in
both
the
residuum
and
limestone
horizons
exhibit
very
low
yields
of
typically
less
than
0.5
gpm.

The
3M
studies
show
that
there
are
two
major
groundwater
plumes
at
the
site.
The
two
groundwater
plumes
are
down
gradient
of
the
inactive
landfill,
and
down
gradient
of
the
chemical
manufacturing
facility.
The
studies
show
that
the
plumes
are
predominantly
confined
beneath
the
site
and
have
negligible
releases
to
the
Tennessee
River.
This
is
consistent
with
the
results
of
3M
surface
water
monitoring,
previously
submitted
to
EPA,
which
show
very
low
PFOA
levels
in
the
river
(
1­
2.65
ppb
in
2000
and
less
than
50
ppt
in
2002).
Page
8
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
The
3M
studies
show
that
there
are
two
major
groundwater
plumes
at
the
site.
The
two
groundwater
plumes
are
down
gradient
ofthe
inactive
landfill,
and
down
gradient
ofthe
chemical
manufacturing
facility.
The
studies
show
that
the
plumes
are
predominantly
confined
beneath
the
site
and
have
negligible
releases
to
the
Tennessee
River.
This
is
consistent
with
the
results
of3M
surface
water
monitoring,
previously
submitted
to
EPA,
which
show
very
low
PFOA
levels
in
the
river
(
1­
2.65
ppb
in
2000
and
less
than
50
ppt
in
2002).

Monitoring
Results
Groundwater
Monitoring
Based
on
its
extensive
site
investigations,
3M
developed
a
PFOA
sampling
and
analysis
program
in
2001
to
assess
the
PFOA
levels
in
the
site
groundwater.
In
developing
its
strategy
for
monitoring
under
the
LOT,
3M
selected
the
following
wells
for
groundwater
sampling
and
PFOA
analysis
going
forward
(
see
attached
site
map):

Monitoring
Location
Site
Condition
Wells
226R
&
L
Wells
220R
and
L
Well
320L
Wells
327R
Wells
310R
&
317L
Located
east
ofinactive
landfill
and
south
of
wastewater
treatment
 
monitors
background
conditions
in
residuum
and
shallow
limestone
groundwater
Located
northeast
ofinactive
landfill
 
monitors
predominant
flow
path
ofplume
in
residuum
and
shallow
limestone
zones
Located
north
of
inactive
landfill
 
monitors
secondary
flow
path
of
plume
Located
in
the
former
incinerator
area
 
monitors
residuum
groundwater
near
source
area
Located
in
the
Chemical
Plant
 
monitors
dominant
groundwater
flow
pathways
in
the
Chemical
Plant
Groundwater
samples
from
the
eight
monitoring
points
were
collected
on
July
15­
16,
2003
and
the
PFOA
results
are
presented
in
the
table
below.
With
the
exception
of
the
Well
31
OR,
these
monitoring
points
are
different
then
those
sampled
in
previous
events,
but
provide
a
more
accurate
representation
of
the
groundwater
conditions
for
the
measurement
of
fluorochemicals.
Page
9
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
As
at
Cottage
Grove,
3M
collected
field
duplicate
samples
during
the
monitoring
to
provide
a
measure
ofthe
precision
associated
with
sample
collection,
preservation
and
storage
as
well
as
laboratory
procedures.
The
laboratory
duplicate
sample
is
taken
in
the
laboratory
and
provides
a
measure
ofthe
precision
associated
with
laboratory
procedures,
but
not
with
sample
collections,
preservation
or
storage
procedures.

As
indicated
in
the
May7,
2003
letter
to
EPA,
these
monitoring
locations
will
be
sampled
again
in
December
2003
and
June
2004
and
a
summaryreport
ofthe
cumulative
data
will
be
provided
on
August
1,
2004.

The
groundwater
data
for
recent
and
previous
monitoring
events
are
shown
in
the
following
Table.

GROUNDWATER
WELL
MONITORiNG
DATA
FOR
THE
3M
DECATUR,
AL
MANUFACTURING
SITE
SAMPLE
ID
SAMPLE
DATE
PFOA
(
ppb)
PFOA
(
ppb)
Lab
Dup
PFOA
(
ppb)
°
Field
Dup
PFOA
(
ppb)
Average
210R
3/
28/
01
1060
996
1000
1018
213R
3/
28/
01
°
223
231
220
224
216R
3/
28/
01
75.7
81.8
79.9
79.1
217R
3/
28/
01
0.091
0.088
0.082
0.087
306R
3/
28/
01
3280
3690
3330
3433
308R
3/
28/
01
107
131
117
355
315R
3/
28/
01
637
635
640
1912
310R
3/
28/
01
1060
1110
1190
1120
310R
7/
16/
03
1570
1560
1590
1573
220R
7/
16/
03
68.2
68.6
65.8
67.5
220L
7/
16/
03
89.2
88.8
90.2
89.4
226R
7/
16/
03
10.6
11.0
10.6
10.7
226L
7/
16/
03
NQ
ND
ND
°
ND
317L
7/
16/
03
0.94
0.95
0.99
0.96
320L
7/
16/
03
ND
ND
NQ
ND
327R
7/
16/
03
2280
2600
2280
2386
As
indicated
by
the
data
presented
in
the
Table,
there
is
a
wide
range
ofPFOA
levels
measured
in
the
groundwater
beneath
the
site.
However,
the
data
suggest
a
low
likelihood
of
off­
site
groundwater
coritamination.
For
example,
the
levels
in
the
well
31
OR
during
two
sampling
events
show
little
change,
which
is
predictable
considering
the
slow
movement
of
ground
water
explained
above.
In
addition,
wells
220L,
226L,
and
31
OL
show
extremely
low
to
non­
detectable
levels
of
PFOA.
These
wells
are
drilled
into
the
aphaltic
limestone,
which
acts
as
the
confining
layer
that
prevents
groundwater
movement
downward.
These
factors
indicate
that
the
groundwater
is
not
moving
off
site
and
therefore
would
not
represent
an
exposure
pathway
for
PFOA.
Page
10
Document
Control
Office
(
DCO)
Office
of
Pollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
Effluent
Monitoring
3M's
Decatur,
Alabama
manufacturing
facilities
obtain
process
water
from
the
City
ofDecatur
Utilities,
and
directly
from
the
Tennessee
River.
In
addition,
many
ofthe
manufacturing
operations
utilize
non­
contact
cooling
water,
which
is
obtained
from
the
Tennessee
River.
All
process
wastewaters
from
the
3M
and
Dyneon
manufacturing
operations
are
treated
in
the
site's
wastewater
treatment
facility.
The
system
contains
both
physical­
chemical
and
biological
treatment.
Process
wastewaters
are
mixed
with
non­
contact
cooling
water
prior
to
discharge
to
the
Tennessee
River.
The
discharge
is
permitted
under
Alabama
NPDES
Permit
No.
AL00002O5.
The
process
wastewater
discharge
and
combined
process
wastewater/
non­
contact
cooling
water
is
designated
as
Outfall
OO1A
and
001,
respectively.

As
explained
in
our
May
7
letter,
wastewater
sampling
at
the
Decatur
site
for
PFOA
analysis
is
being
conducted
on
a
quarterly
basis.
Samples
are
collected
at
Outfall
001,
which
consists
of
treated
process
wastewater
and
non­
contact
cooling
water.
The
outfall
discharges
to
Baker's
Creek,
which
in
turn
empties
into
the
Tennessee
River.
All
samples
are
collected
as
24­
hour
composites
and
duplicated
analysis
is
conducted
for
each
sample.
The
specific
sampling
and
analytical
protocols
were
described
in
3M'sMay
7,
2003
letter
to
EPA.

The
following
table
presents
the
PFOA
monitoring
results
for
the
Decatur
wastewater
effluent
discharged
under
Alabama
NPDES
Permit
No.
AL000205,
Outfall
001.
The
data
summary
includes
the
historical
data
and
the
2003
monitoring
events.

3M
Decatur
2nd1
Quarter,
2003
and
Historical
Events
Outfall
001
FC
Sampling
Results
Sample
Date
Results
J
Duplicate
j
Average
.

(
all
values
are
listed
as
ugh)
1998
N/
A
N/
A
[
602
1999
N/
A
N/
A
[
766
2000
N/
A
N/
A
1028
2001
N/
A
N/
A
310
January,
2003
N/
A
N/
A
[
58
May
28,
2003
89.0
87.5
°
[
88.3
As
indicated
by
these
data,
there
has
been
a
decrease
in
the
levels
ofPFOA
in
the
effluent
discharged
to
the
Tennessee
River.
The
overall
reduction
throughout
these
5
years
is
mainly
a
result
ofthe
production
phase­
out
ofPFOA
at
this
site,
and
the
improvements
in
the
fluoropolymer
productionprocess
occurring
at
the
Dyneon
operation.
Continued
decreases
in
thO
effluent
concentration
are
anticipated
because
ofongoing
process
improvement
efforts.
Page
11
Document
Control
Office
(
DCO)
Office
ofPollution
Prevention
and
Toxics
(
OPPT)
US
Environmental
Protection
Agency
In
addition,
the
results
ofTennessee
River
surface
water
monitoring
recently
submitted
to
the
AR­
226
Docket
indicate
that
PFOA
levels
in
the
river
have
declined
significantly
as
well.
In
fact,
PFOA
levels
downstream
from
the
3M
Decatur
Outfall
are
below
detectable
limits
of
0.050
ppb.

HISTORIC
MONITORING
DATA
SUBMISSION
As
noted
in
the
LOT,
3M's
monitoring
programs
for
the
Cottage
Grove
and
Decatur
sites
have
included
sampling
results
for
other
fluorocheniicals
besides
PFOA.
While
much
ofthis
information
has
been
reported
to
local
agencies,
3M
is
shortly
providing
a
comprehensive
summary
ofresults
from
those
monitoring
programs
as
part
ofa
separate
submission
to
the
AR­
226
Docket.

In
summary,
this
letter
reports
results
ofwastewater
and
groundwater
monitoring
at
the
Decatur
and
Cottage
Grove
sites.
These
data
fulfill
the
commitments
of3M
and
Dyneon
under
the
March
13,
2003
3M
LOT
and
the
March
14,
2003
APFO
Users
LOT.
If
there
are
any
questions,
please
contact
the
writer
at
the
address
provided
below.

Sincerely,

Michael
A.
Santoro
Director,
Environmental,
Health,
Safety
and
Regulatory
Affairs
3M
­
Bldg.
236­
lB­
TO
P.
O.
Box
33331
St.
Paul,
MN
55144
651
733­
6374
(
phone)
651
733­
1958
(
fax)
E­
mail:
masantoro@
mnnmcom
cc:
Mary
Dominiak
 
Room
4410
Attachments
3M
COTTAGE
GROVE
HISTORIC
GROUNDWATER
MONITORING
DATA
SUMMARY
Sample
ldentiftcatiop1
Date
Sampled
PFOA
(
ppb)
PFOA
lab
dup
(
ppb)

MW­
1O1
12/
03/
02
170
180
172
°
04/
01/
03
NQ
NQ
NQ
05/
19/
03
NQ
°­
NQ
NQ
MW­
102
12/
03/
02
04/
01/
03
05/
19/
03
324
°
NQ
NQ
404
NQ
NQ
°
369
NQ
NQ
PW­
2
°
06/
10/
01
06/
28/
01
09/
07/
01
10/
31/
01
11/
12/
01
0.491
2.64
0.359
2.46
0.765
0.473
2.84
0.395
2.21
0.706
0.577
10.70
0.405
2.15
0.356
PW.
3
°
06/
10/
01
06/
28/
01
09/
07/
01
10/
31/
01
11/
12/
01
0.6
0.763
0.716
0.519
0.721
0.561
0.772
°

0.693
0.542
0.713
0.554
0.778
0.737
0.615
0.739
PW­
4
06/
10/
01
06/
28/
91
09/
07/
01
10/
31/
01
11/
12/
01
°
1.170
0.851
0.823
14.000
°

0.792
1.110
1.000
0.816
13.500
0.755
1.180
0.988
0.782
4.100
0.827
PW­
5
.
06/
10/
01
06/
28/
01
09(
07(
01
10/
31/
01
11/
12/
01
42.500
26.900
28.600
40.800
20.900
45.700
30.100
27
.500
39.400
21,800
56.400
NA
28.700
39.700
22.600
PW­
6
07/
11/
01
09/
07/
0
1
10/
31/
01
11/
12/
01
138.000
NA
11.600
91.600
132.000
NA
11.200
93.300
NA
NA
14.000
93.900
Water
Supply
Distribution
Loop
at
Cafeteria
116
07/
11/
01
10/
31/
01
11/
12/
01
1.230
40.600
11.400
1.140
38.500
10.800
NA
41.100
17.100
PZ­
14
09/
07/
01
10)
31/
01
11/
12/
01
6.400
5.890
4.660
6.770
4.960
4.630
6.060
5.250
4.600
SPIOO
09/
07/
01
10/
31/
01
11/
12/
01
°
0.623
0.547
0.593
0.566
0.523
0.577
0.614
0.578
0.561
Trap
Range
Well
09/
07/
01
0.541
0.565
0.571
MW­
4
10/
31/
01
11/
12/
01
5.670
5.300
5.930
5.110
7.390
5.450
MW­
14
09/
07/
01
10/
31/
01
11/
12/
01
846.000
840.000
780.000
845.000
824.000
836.000
848.000
730.000
858.000
Notes
1.
ND.
Not
detected
2.
NQ
 
Not
quantitated
3.
NA
 
Not
Analyzed
3M
DECATUR
MANUFACTIRUNG
FACILITY
SITE
MAP
LOCATION
OF
MONITORING
WELLS
LEGEND
°
Monltcrwdll
Sampkd
3l28~
fO1
200
0
200
400
Feet
°
°
°
°
;

°
°°°°
°

I
I
~
I
i~
o
L~
~
\\
I
­
t~~:~

.4~._..°
~

1~
°
°
~
c
j
~
°\
~
cN~
cP'
~

°
°°`\
N
°°
\.~
~_~:

`~­`
4~­~<­~
:
1:

Figure
1
Monitoring
Points
3M
­
Cottage
Grove
Facility
°
°
Production
Wells
°
0
Monitoring
Wells
°
Other
$
ampling
Points
33
34
°
°
f
it
­
a
­°°~°
NewDl
Monitoring
Wells
1,500
750
0
t,
500
cc'
