Document ID: EPA-HQ-OPP-2003-0349-0008
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2003-12-12T05:00Z

1http://
www.
sfwmd.
gov/
curre/
pest/
pestindex.
htm
2One
site
listed
as
C25599
(
in
two
reports)
or
C25S99
(
in
one
report)
was
not
on
the
map.
Instead
the
map
shows
the
similarly
named
site
S99
has
been
highlighted
in
green.

3The
largest
value
was
entered
in
the
table
with
comment
code
"
A"
which
was
not
explained
in
the
table
footnotes,
or
mentioned
in
the
report
text
Date
SITE
Flow
Conc
Comments
12/
15/
98
G94D
yes
1.2
"
A"
 
not
explained
12/
15/
98
ACME1DS
yes
0.64
<
quant.
Limit
08/
09/
99
G94D
yes
0.72
<
quant.
Limit
08/
09/
99
ACME1DS
yes
0.56
<
quant.
Limit
08/
10/
99
C25599
no
0.6
<
quant.
Limit
05/
03/
00
L3BRS
(
1)
no
0.56
05/
04/
00
GORDYRD
no
0.29
<
quant.
Limit
05/
04/
00
C25S99
no
0.29
<
quant.
Limit
03/
20/
01
CR33.5T
no
0.39
<
quant.
Limit
03/
21/
01
S38B
no
0.21
<
quant.
Limit
05/
16/
01
G123
yes
0.86
05/
16/
01
S142
reverse
0.89
05/
16/
01
L3BRS
no
0.21
<
quant.
Limit
05/
21/
01
GORDYRD
no
0.71
05/
22/
01
S79
no
0.24
<
quant.
Limit
08/
14/
01
C25S99
yes
0.21
<
quant.
Limit
08/
14/
01
GORDYRD
yes
0.23
<
quant.
Limit
Table
1.
SFWMD
detections
of
diuron,
1998
 
2001
Diuron
detections
in
south
Florida
surface
water
The
South
Florida
Water
Management
District
(
SFWMD)
has
available
on
its
website1,
reports
of
pesticide
monitoring
between
December
1998
to
August
2001.
The
SFWMD
monitored
several
locations
(
see
attached
map)
approximately
once
every
three
months
for
three
years.
Out
of
the
twelve
months
in
which
sampling
occurred,
diuron
was
observed
in
six.
Locations
of
the
diuron
detections
have
been
highlighted
in
red
on
the
map2.
Over
the
three
year
period
there
were
17
detections
of
diuron
out
of
438
samples.
Five
of
the
detections
showed
concentrations
above
the
limit
of
quantitation,
with
the
highest
value3
reported
at
1.2
F
g/
L.
Detection
and
quantitation
limits
changed
over
the
course
of
the
studies.
Samples
taken
in
1998
and
1999
had
detection
limits
of
0.4
F
g/
L
and
a
quantitation
limit
of
0.8
F
g/
L;
samples
taken
in
2000
and
2001
had
limits
at
half
these
values.

The
approximate
locations
of
the
SFWMD
samples
are
shown
on
the
modified
SFWMD
map
(
Figure
1).
The
hydrology
of
south
Florida
is
complex
because
of
the
large
number
of
man­
made
canals,
and
it
is
thus
difficult
to
determine
whether
locations
are
downstream
of
each
other,
or
of
agricultural
areas.
For
example,
site
CR33.5T
on
the
map,
may
not
be
downstream
of
the
large
citrus
area
just
to
its
east.

Because
monitoring
was
carried
out
only
four
times
per
year,
there
is
a
high
likelihood
of
missing
peak
concentrations.
The
data
cannot,
therefore,
be
used
to
estimate
the
peak
concentration
of
diuron
in
Florida
waters,
and
probably
gives
only
a
rough
estimate
of
average
concentrations
in
the
region.
Figure
1.
SFWMD
monitoring
locations.
This
map
is
taken
from
the
SFWMD
report
from
August
2001
has
locations
of
diuron
detection
highlighted
in
color.