1
UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
MEMORANDUM
SUBJECT:
ORYZALIN
TRED:
Estimated
Drinking
Water
Concentrations
for
Oryzalin
for
Use
in
the
Human
Health
Drinking
Water
Risk
Assessment.
PC
Code:
104201
DP
Barcodes:
D209537
FROM:
Iwona
Maher,
Chemist
Sid
Abel,
Branch
Chief
Pat
Jennings,
Risk
Assessment
Process
Leader
Environmental
Risk
Branch
1
Environmental
Fate
and
Effects
Division
(
7507C)

TO:
Thurston
Morton,
Chemist
Reregistration
Branch
IV
Health
Effects
Division
(
7509C)

Gary
Mullins,
Chemical
Review
Manager
Reregistration
Branch
III
Special
Review
and
Reregistration
Division
(
7508C)

Attached
is
the
EFED
drinking
water
assessment
for
the
tolerance
reassessment
for
oryzalin
and
the
data
evaluation
records
for
two
soil
adsorption/
desorption
studies
(
MRIDs:
43433201
and
43433202;
Appendix
III)
submitted
by
the
registrant.
Oryzalin
was
first
registered
in
1974.
A
Registration
Standard
was
issued
in
June,
1987
(
NTIS#
PB89­
102396)
and
an
oryzalin
Reregistration
Eligibility
Decision
(
RED)
was
issued
in
September
1994.

Oryzalin
is
a
pre­
emergent,
surface
applied
herbicide
used
to
control
many
annual
grasses
and
certain
broad
leaf
weeds.
Its
agricultural
uses
include
berries,
vine
and
orchard
crops
(
i.
e.,
citrus
fruits,
pome
and
stone
fruits,
and
tree
nuts)
and
non­
agricultural
uses
include
ornamentals,
Christmas
trees,
non­
bearing
fruit
and
nut
trees,
non­
bearing
vineyards
and
berries,
and
established
warm
season
turf.
2
Tier
II
PRZM/
EXAMS
modeling
was
performed
to
estimate
the
drinking
water
concentrations
for
the
human
health
dietary
risk
assessment.
Estimated
environmental
concentrations
were
based
on
modeling
a
subset
of
the
agricultural
use
scenarios
to
capture
oryzalin's
crop
and
non­
crop
use
spectrum,
regional
differences
between
the
west
and
east
coast,
and
the
differences
in
method
of
applications
and
formulation.
The
scenarios
that
were
modeled
are
California
almonds
(
ground
and
aerial
application),
North
Carolina
apples
(
ground
application),
Florida
citrus
(
ground
application),
Oregon
Christmas
trees
(
ground
application),
and
Pennsylvania
turf
(
granular
application
via
broadcast
spreader).
The
most
conservative
estimates
were
obtained
for
ground
application
of
oryzalin
to
Florida
citrus
at
the
maximum
labeled
annual
application
rate
on
12
lb
a.
i./
acre,
applied
twice
annually
at
6
lb
a.
i./
acre
with
an
interval
between
applications
of
60
days.
For
the
purpose
of
estimating
acute
risks,
the
predicted
1
in
10
year
annual
peak
concentration
of
oryzalin
in
drinking
water
from
surface
water
is
198
ppb.
For
evaluating
chronic
non­
cancer
concerns,
the
estimated
1
in
10
year
annual
mean
concentration
of
oryzalin
in
drinking
water
is
12.7
ppb.
For
evaluating
concerns
for
cancer,
the
36­
year
annual
mean
concentration
is
9.2
ppb.
This
assessment
was
based
on
the
incorporation
of
oryzalin
shortly
after
application.
Both
acute
and
chronic
concentrations
for
all
other
scenarios
were
significantly
lower.

SCI­
GROW
modeling
predicted
ground
water
concentrations
of
oryzalin
at
the
annual
application
rate
of
12
lb
a.
i./
acre
(
i.
e.,
two
applications
of
6
lb
a.
i./
acre)
of
0.93
ppb
in
drinking
water
from
shallow
ground
water
sources.
This
concentration
may
be
considered
as
both
the
acute
and
chronic
upper
bound
value
for
use
in
the
human
health
risk
assessment.
3
Drinking
Water
Assessment
for
the
Tolerance
Reassessment
of
Oryzalin
Use
on
Multiple
Crops
PC
Code
104201
I.
SUMMARY
AND
CONCLUSIONS
Oryzalin
is
a
pre­
emergent,
surface
applied
herbicide
used
to
control
many
annual
grasses
and
certain
broad
leaf
weeds.
The
herbicide
was
first
registered
in
1974.
A
Registration
Standard
was
issued
in
June,
1987
(
NTIS#
PB89­
102396).
Prior
to
the
issuance
of
the
Registration
Standard,
several
agricultural
crops
were
deleted.
The
only
food
crop
groups
remaining
on
oryzalin
labels
are
berries,
vine
and
orchard
crops
(
i.
e.,
citrus
fruits,
pome
and
stone
fruits,
and
tree
nuts).
In
addition,
oryzalin
has
many
non­
food
uses
including
ornamentals,
Christmas
trees,
non­
bearing
fruit
and
nut
trees,
non­
bearing
vineyards
and
berries,
and
established
warm
season
turf.
An
Oryzalin
Reregistration
Eligibility
Decision
(
RED)
was
issued
in
September
1994.

Formulations
of
oryzalin
include:
granular,
wettable
powder,
water
dispersible
granulars,
flowable
concentrate
and
liquid.
All
liquid
formulations
can
be
applied
by
ground
broadcast
application,
band
application,
or
chemigation.
Additionally,
aerial
application
is
labeled
in
California.
Dry
(
granular)
formulations
are
applied
via
broadcast
spreader.
To
estimate
the
drinking
water
concentrations
for
human
health
dietary
risk
assessment,
Tier
II
PRZM/
EXAMS
modeling
was
performed
for
use
on
California
almonds
(
ground
and
aerial
application),
North
Carolina
apples
(
ground
application),
Florida
citrus
(
ground
application),
Oregon
Christmas
trees
(
ground
application),
and
Pennsylvania
turf
(
granular
via
broadcast
spreader)
with
soil
incorporation
shortly
after
application
.
The
most
conservative
surface
water
estimates
were
obtained
for
ground
application
of
oryzalin
to
Florida
citrus
at
the
maximum
annual
application
rate
on
the
label
of
12
lb
a.
i./
acre,
applied
twice
annually
at
6
lb
a.
i./
acre
with
an
interval
between
applications
of
60
days.
For
the
purpose
of
estimating
acute
risks,
the
predicted
1
in
10
year
annual
peak
concentration
of
oryzalin
in
drinking
water
from
surface
water
is
198
ppb.
The
simulated
1
in
10
year
annual
mean
(
chronic
non­
cancer)
and
36­
year
annual
mean
(
chronic
cancer)
concentrations
4
of
oryzalin
in
drinking
water
are
12.7
ppb
and
9.2
ppb,
respectively.
Both
acute
and
chronic
concentrations
for
all
other
scenarios
were
significantly
lower
including
the
scenario
of
aerial
application
on
California
almonds.

SCI­
GROW
modeling
predicted
a
concentration
of
oryzalin
uses
at
the
annual
application
rate
of
12
lb
a.
i./
acre
(
i.
e.,
two
applications
of
6
lb
a.
i./
acre)
as
0.93
ppb
in
drinking
water
from
shallow
ground
water
sources.
This
concentration
may
be
considered
as
both
the
acute
and
chronic
upper
bound
value
for
use
in
the
human
health
risk
assessment.

Ground
and
surface
water
concentrations
were
not
estimated
for
the
major
degradate
of
oryzalin,
4­
hydroxy­
3,5­
dinitrosulfanilamide
(
OR­
20).
Laboratory
fate
studies
indicate
that
OR­
20
has
an
average
half­
life
of
58
days
with
K
ads
ranging
from
0.165
to
0.310.
These
data
would
indicate
the
potential
to
underestimate
environmental
exposures
should
OR­
20
be
toxicologically
important.

Based
on
laboratory
data,
oryzalin
is
moderately
persistent
and
mobile
in
sandy
soil
with
low
organic
matter
content.
The
chemical
is
stable
to
hydrolysis
and
appears
to
be
susceptible
to
rapid
direct
photolysis
in
water
with
a
half­
life
of
1.4
hrs.
Therefore,
it
is
not
expected
to
persist
in
clear
shallow
surface
waters
exposed
to
sunlight.
On
the
soil
surface
oryzalin
appears
to
photodegrade
rather
rapidly
with
a
half­
life
of
3.8
days.
Under
aerobic
conditions
oryzalin
biodegrades
slowly,
with
a
half­
life
of
2.1
months.
Under
anoxic
conditions
it
undergoes
reduction
more
readily,
with
a
half­
life
of
10
days.
Based
on
terrestrial
field
dissipation
studies,
it
appeared
to
be
moderately
persistent
under
field
conditions,
its
dissipation
half­
lives
ranged
from
58
to
77
days.

Oryazlin
appears
to
have
a
greater
potential
to
contaminate
surface
water
via
spray
drift
than
via
runoff
to
nearby
surface
water.
According
to
the
McCall
classification
(
McCall
et
al.,
1980),
oryzalin
appears
to
be
mobile
in
sand
and
sandy
loam,
relatively
mobile
in
loam,
and
immobile
in
clay
loam.
It
is
probably
unlikely
that
oryzalin
would
reach
ground
water.
However,
in
sandy
soils
and
under
some
environmental
conditions,
such
as
excess
precipitation,
or
where
soil
preferential
flow
conditions
exist
and
exposure
to
sunlight
is
minimal,
oryzalin
residues
may
leach
into
ground
water.
If
oryzalin
reaches
ground
water,
it
probably
will
readily
undergo
reduction
to
more
polar
compounds.

Some
of
oryzalin
degradates
formed
in
aerobic
soil
metabolism
may
potentially
leach
into
ground
water.
The
major
degradate,
4­
hydroxy­
3,5­
dinitrosulfanilamide
(
OR­
20),
is
very
mobile
and
moderately
persistent
and,
therefore,
has
a
potential
for
leaching.
Oryzalin
degradates
were
not
monitored
under
field
conditions.

Fate
and
transport
data
for
oryzalin
were
sufficient
to
characterize
drinking
water
exposure.
Only,
the
aerobic
and
anaerobic
aquaticc
metabolism
studies
were
not
submitted.
Fate
data
submitted
for
oryzalin
degradates
were
limited
to
two
soil
adsorption/
desorption
studies.
If
there
are
human
and/
or
ecotoxicological
concerns
associated
with
oryzalin
degradates,
a
new
terrestrial
field
dissipation
and/
or
more
comprehensive
laboratory
data
for
oryzalin
degradates
may
be
requested.

II.
USAGE
PROFILE
5
Oryzalin
is
a
selective
pre­
emergent,
surface
applied,
herbicide
from
the
dinitroaniline
family.
The
herbicide
is
used
to
control
annual
grasses
and
many
broadleaf
weeds
in
citrus,
fruit
and
nut
trees,
berries,
vineyards,
turf,
ornamentals
and
Christmas
tree
plantations.
It
is
manufactured
in
granule,
wettable
powder,
water
dispersible
granule,
flowable
concentrate
and
liquid.
Liquid
formulations
are
applied
via
ground
broadcast
application,
band
application,
aerial
application,
and
chemigation.
Granular
formulation
is
applied
via
broadcast
spreader.
The
pre­
emerged
herbicide
is
soil
incorporated
via
½
­
1
inch
of
rainfall,
sprinkler
irrigation
or
a
shallow
cultivation
of
1­
2
inches
within
21
days.
Table
1
provides
label
information
for
these
crop
and
non­
crop
uses
that
were
selected
for
modeling
purposes.
6
Table
1.
Oryzalin
label
information
for
selected
major
uses
Crop
and
Non­
crop
Uses
Method
of
Application
Max.
Single
Application
Rate
(
lbs
ai/
acre)
Min.
Application
Intervals
(
days)
Max.
Number
of
Applications
Max.
Annual
Application
Rate
(
lbs
ai/
acre)
Formulation
%
AI
EPA
Reg.
No.

Golf
Course
Turf
Spreader
2
90
3
6
Turf
Pride
G
0.5%
ai
035512­
00029
Christmas
Trees
Directed
Spray
4
60
2
8
Surflan
EC
40.4%
ai
062719­
00112
Almond
Broadcast
Air
Sprayed
­
CA
only
6
3.9
75
90
2
NS
12
12
Surflan
DF
 
85%
ai
062719­
00138
Surflan
75
W­
75%
ai
62719­
110
Apples
Broadcast
6
75
2
12
Surflan
DF
85%
ai
062719­
00138
Citrus
Broadcast
6
60
2
12
Surflan
EC
40.4%
ai
062719­
00112
NS
 
not
specified
on
label
III.
APPROACH
TO
DRINKING
WATER
ASSESSMENT
A
drinking
water
assessment
for
parent
oryzalin
was
conducted
for
three
agricultural
scenarios:
CA
almonds,
NC
apples,
and
FL
citrus.
Oryzalin
was
applied
via
aerial
(
CA
almonds
only)
and
ground
application
at
the
maximum
rate
of
12
lb
ai/
acre
annually
with
two
applications
of
6
lb
a.
i./
acre.
Additionally,
the
assessment
was
performed
for
two
non­
agricultural
scenarios:
PA
golf
course
turf
at
a
maximum
annual
ground
application
rate
of
6
lb
ai/
acre
with
three
application
of
2
lb
a.
i./
acre,
and
OR
Christmas
trees
at
a
maximum
annual
ground
application
rate
of
8
lb
ai/
acre
with
two
application
of
4
lb
a.
i./
acre.
This
assessment
was
based
on
oryzalin
incorporation
shortly
after
application.

Tier
II
modeling
employing
PRZM­
EXAM
was
performed
to
estimate
drinking
water
concentrations
from
surface
water
sources
and
the
SCI­
GROW
model
was
used
to
predict
drinking
water
concentrations
of
oryzalin
from
ground
water
sources.

IV.
ENVIRONMENTAL
FATE
SUMMARY
The
major
route
of
oryzalin
disappearence
is
aqueous
photolysis,
photodegradation
on
soil
surface,
and
reduction
under
anaerobic
condition.
Oryzalin
appears
to
degrade
slowly
under
aerobic
soil
conditions
and
is
stable
to
hydrolysis.
Under
field
conditions
oryzalin
appeared
to
be
moderately
persistent,
with
a
half­
life
of
about
two
months.

Oryzalin
has
the
potential
to
contaminate
surface
water
via
spray
drift.
If
there
is
little
or
no
exposure
to
sunlight,
runoff
may
contribute
to
the
surface
water
contamination
in
the
event
of
significant
rainfall
occurring
after
application
prior
to
soil
incorporation.
Although
oryzalin
does
not
appear
to
be
mobile
under
field
conditions,
the
soil/
water
partition
coefficients
indicate
that
chemical
mobility
will
vary
from
mobile
to
immobile
depending
on
soil
type
and
organic
matter
content.
Oryzalin
is
less
likely
to
contaminate
ground
water
resources
due
to
reduction
in
the
7
anaerobic
soil
layer.
However,
in
sandy
soils
under
some
environmental
conditions,
such
as
excess
precipitation,
or
where
soil
preferential
flow
conditions
exist
and
exposure
to
sunlight
is
minimal,
oryzalin
residues
may
leach
into
ground
water
and
undergo
reduction
to
more
polar
compounds.

Laboratory
studies
indicate
that
oryzalin
is
stable
to
hydrolysis
(
MRID
41378401)
but
exhibits
susceptibility
to
rapid
direct
aqueous
photolysis;
the
aqueous
photolytic
half­
life
is
1.4
hours
(
MRID
41288701).
The
chemical
also
readily
photodegrades
on
the
soil
surface
with
an
extrapolated
half­
life
of
3.8
days
(
sunlight
equivalent
nonlinear
half­
life,
MRID
41050001).

Oryzalin
degrades
aerobically
with
a
half­
life
of
63
days
in
sandy
loam
soil
(
MIRD
41322801).
Out
of
nine
metabolites
formed,
three
(
4­
hydroxy­
3,5­
dinitrosulfanilamide
(
OR­
20),
2­
ethyl­
7­
nitro­
1­
propyl­
1H­
benzimidazole­
5­
sulfonamide
3­
oxide
(
UN­
2),
and
the
unidentified
compound
UN­
3;
MRID
43433202)
appeared
to
be
very
mobile.
Others
were
relatively
mobile
or
immobile.
Under
anaerobic
conditions
oryzalin
nitro
groups
undergo
reduction
to
amines,
dealkylation,
and
ring
formation
to
produce
benzimidazoles,
with
a
half­
life
of
10
days
(
MRID
41322802).
Major
anaerobic
metabolites
are
7­
amino­
2­
ethyl­
1­
propyl­
1H­
benzimidazole­
5­
sulfonamide
(
i.
e.,
OR­
14;
10.3%
of
time
zero
radioactivity)
and
7­
amino­
2­
ethyl­
1H­
benzimidazole­
5­
sulfonamide
(
i.
e.,
OR­
16;
5.3
%
of
time
zero
radioactivity).
The
highly
polar
degradation
products
are
associated
with
soil
organic
matter.
Soil
binding
of
oryzalin
residues
appears
to
be
an
important
route
of
dissipation.
In
an
aerobic
soil
metabolism
study,
oryzalin
non­
extractible
residues
(
i.
e.,
parent
and
metabolites)
increased
to
63.1%
of
time
zero
radioactivity
at
six
months
posttreatment
(
PTT)
and
to
70.6%
of
time
zero
radioactivity
at
60
days
PTT
in
an
anaerobic
study.
Formation
of
CO
2
and/
or
volatile
degradation
products
was
not
a
major
route
of
dissipation
for
oryzalin
in
both
aerobic
and
anaerobic
metabolism
studies.

Substantial
quantities
of
oryzalin
could
also
be
available
for
runoff
for
a
few
days
to
months
postapplication
depending
on
the
degree
of
exposure
to
sunlight
(
photodegradation
on
soil
half­
life
of
3.8
days;
aerobic
soil
half­
life
=
2.1
months;
terrestrial
field
dissipation
half­
lives
of
77­
146
and
58­
138
days).
The
low
to
intermediate
soil/
water
partitioning
of
oryzalin
(
K
d
=
2.1,
4.9,
8.4,
and
12.9;
MRID
41479802)
indicates
that
fractions
of
oryzalin
could
be
organic
carbon
transported
via
both
dissolution
in
runoff
water
and
adsorption
to
eroding
soil.
Based
on
its
resistance
to
abiotic
hydrolysis
coupled
with
only
a
moderate
susceptibility
to
aerobic
and
anaerobic
biodegradation
indicate
that
it
will
be
somewhat
more
persistent
in
receiving
surface
waters
that
are
deeper,
have
high
light
attenuation,
low
microbiological
activities
and
long
hydrological
resident
times.

While
it
appears
that
most
of
the
applied
oryzalin
either
binds
to
soil
or
degrades,
some
oryzalin
degradates
may
have
high
potential
for
leaching.
Parent
oryzalin
would
be
most
mobile
in
coarse,
wet,
alkaline
soils
with
little
organic
matter.
However,
parent
oryzalin
would
not
be
stable
if
it
was
to
leach
into
groundwater.
Anaerobic
conditions
below
the
soil
surface
would
result
in
reduction
of
the
compound
to
more
polar
degradates.
At
least
three
oryzalin
degradates,
OR­
20,
UN­
2
and
UN­
3,
formed
in
aerobic
soil
metabolism
(
MRID
43433202),
have
the
potential
to
leach
into
ground
water.
The
major
degradate
(
MIRD
41322801),
OR­
20,
is
moderately
persistant
and
has
a
very
high
potential
for
leaching.
The
degradate
appears
to
be
very
mobile
in
sand,
sandy
loam,
and
loam
soils,
with
Freundlich
K
ads
values
ranging
from
0.165
to
0.310
(
MRID
43433201).
Under
aerobic
conditions,
in
different
soils,
OR­
20
appears
to
degrade
with
the
8
average
half­
lives
(
t
1/
2)
of
58
days
(
based
on
a
formation­
decline
curve;
Tables
IX
through
XII,
163­
1,
MRID
43433202)
and
102
days
(
based
on
a
formation­
decline
curve;
162­
1,
MRID
41323801).
Apparent
K
d
values
for
UN­
2
ranged
from
0.89­
4.52
L/
kg
and
for
UN­
3
ranged
from
1.50­
4.85
L/
kg
with
the
exception
of
12.19
L/
kg
in
the
sand
soil
(
MRID
43433202).
The
OR­
20
degradate
and
other
degradates
have
not
been
monitored
in
the
field.
Their
persistence
in
natural
waters
is
unknown.

In
the
field,
oryzalin
appears
to
degrade
slowly
with
a
half­
life
of
68
days
in
Florida
sand
soil
and
a
first
phase
half­
life
of
58
in
California
loam
soil
and
77
days
in
Michigan
silty
clay
loam
soil.
The
second
phase
half­
lives
were
138
days
in
California
loam
soil
and
146
days
in
Michigan
silty
clay
loam
soil.
Parent
oryzalin
did
not
appear
to
be
mobile
under
field
conditions.
The
parent
was
undetectable
and
always
less
than
detection
limits
(
i.
e.,
0.01
ppm;
MRID
42138001)
below
12
inches
of
soil
depth.
Oryzalin
degradates
were
not
monitored
in
the
field
dissipation
studies
submitted.

Based
upon
its
relatively
low
to
intermediate
soil/
water
partitioning,
significant
fractions
of
the
oryzalin
in
receiving
surface
waters
should
exist
both
dissolved
in
the
water
column
and
adsorbed
to
suspended
and
bottom
sediment.
The
reported
BCFs
for
oryzalin
(
32X
to
106X)
indicate
that
the
bioaccumulation
potential
of
oryzalin
is
relatively
low.

V.
DRINKING
WATER
ASSESSMENT
Monitoring
data
for
oryzalin
in
surface
water
and
ground
water
were
not
found.
Oryzalin
is
not
included
in
National
Water­
Quality
Assessment
(
NAWQA)
Program,
USGS.
Concentrations
of
oryzalin
in
surface
water
and
ground
water
were
estimated
via
modeling.

A.
Surface
Water
Assessment
For
the
drinking
water
assessment,
a
Tier
II
PRZM­
EXAMS
(
PRZM
3.12
and
EXAMS
2.975)
modeling
simulation
was
performed
using
the
index
reservoir
(
IR)
scenario
and
the
percent
cropped
area
(
PCA)
adjustment
factor
for
the
uses
of
oryzalin
selected
for
non­
crops
(
i.
e.,
golf
courses
and
Christmas
trees)
and
crops
(
i.
e.,
almonds,
citrus,
and
apples)
that
would
result
in
the
highest
estimated
environmental
concentrations
from
the
available
combinations
of
crop
and
location.
For
apples
and
almonds,
label
instructions
propose
oryzalin
to
be
ground
applied
twice
at
6
lbs
ai/
acre
with
a
2.5­
month
interval
between
applications.
For
citrus,
label
instructions
were
the
same
as
for
appleas
and
almonds
except
the
interval
between
applications
was
60
days.
The
California
almonds
scenario
in
which
oryzalin
was
aerially
applied
simulated
thee
applications
of
3.9
lbs
a.
i./
acre
with
90
day
intervals
between
applications.
The
Christmas
tree
scenario
simulated
two
applications
of
4
lbs
ai/
acre
with
a
2­
month
interval
between
applications.
The
golf
course
scenario
simulated
three
applications
of
2
lbs
ai/
acre
with
a
3­
month
interval
between
applications
per
proposed
label.

Oryzalin
is
a
surface­
applied
herbicide
in
citrus,
fruit
and
nut
trees,
berries,
vineyards,
turf,
ornamentals
and
Christmas
tree
plantations.
The
pre­
emergent
herbicide
is
soil
incorporated
via
½
­
1
inch
of
rainfall
or
sprinkler
irrigation
or
a
plowed
to
a
depth
of
1­
2
inches
within
21
days
9
after
application.
For
the
purpose
of
modeling
it
was
assumed
that
soil
incorporation
was
achieved
via
1
inch
of
rainfall
immediately
after
application
for
all
crops
except
for
turf,
where
granular
formulations
are
soil­
applied
and
default
soil
incorporation
depth
of
4
cm,
with
concentration
linearly
decreasing
with
depth
selected
(
CAM
=
1).

A
graphical
interface
shell
(
April
5,
2002),
the
pe3.
pl
program,
was
used
to
facilitate
putting
chemical
and
use­
specific
input
values
into
the
proper
positions
in
the
PRZM
input
and
the
EXAMS
chemical
files.
Tables
2
and
3
list
the
modeling
input
parameters.
The
PRZM/
EXAMS
output
files
for
oryzalin
uses
on
golf
courses,
Christmas
trees,
almonds,
citrus,
and
apples
are
presented
in
Appendix
I.
10
Table
2.
Environmental
Fate
and
Chemistry
Input
Parameters
for
Oryzalin
Parameters
Input
Value
and
Unit
Source
of
Info/
Reference
Maximum
per
event
Application
Rates
(
Product
Labels)
by
crop
modeled
Golf
Course
Turf
=
2
lb
ai/
A
Christmas
Trees
=
4
lb
ai/
A
Almonds
=
6
lb
ai/
A
(
ground)
Almonds
=
3.9
lb
ai/
A
(
aerial)
Apples
=
6
lb
ai/
A
Citrus
=
6
lb
ai/
A
Product
Labels:
TURF
PRIDE
12­
00­
12
w/
SURFLAN
(
granular);
EPA
Reg.
No.
035512­
00029
SURFLAN
A.
S.;
EPA
Reg.
No.
062719­
00112
SURFLAN
DF;
EPA
Reg.
No.
062719­
00138
SURFLAN
75
W;
EPA
Reg.
No.
62719­
00110
SURFLAN
DF;
EPA
Reg.
No.
062719­
00138
SURFLAN
A.
S.;
EPA
Reg.
No.
062719­
00112
Maximum
Number
of
Applications
Golf
Course
Turf
=
3
Almonds
=
3
(
aerial)
1
All
Other
=
2
Product
labels
as
above
Minimum
interval
between
applications
Golf
Course
Turf
=
90
days
Christmas
Trees
=
60
days
Almonds
=
75
days
(
ground)
Almond
=
90
(
aerial)
Apples
=
75
days
Citrus
=
60
days
Product
labels
as
above
Method
of
Application
(
with
2
cm
soil
incorporation
depth
except
turf
4
cm)
Golf
Course
=
granular
broadcast
Christmas
Trees
=
direct
spray
Almonds
=
aerial
&
broadcast
Apples
=
broadcast
Citrus
=
broadcast
Product
labels
as
above
Soil
Partition
Coefficient
(
Koc)
2
941
L
kg
o.
c.­
1
MRID
41479802
(
GLN
163­
1)

Molecular
Weight
346.35
Registrant
data
Solubility
2.5
mg/
l
at
25
oC
MRID
41208101­
2
Vapor
Pressure
1
x
10­
7
mm
Hg
at
25
oC
MRID
40454801
Henry's
Law
Constant
1.82
x
10­
8
atm
·
m3/
mol
Calculated
from
solubility
and
vapor
pressure
Aerobic
Soil
Metabolism
T1/
2
3
189
days
MRID
41322801
(
GLN
162­
1)

Aqueous
Photolysis
(
pH
5)
T1/
2
0.06
days
MRID
41278701
Hydrolysis
T1/
2
(
pH7)
stable
MRID
41378401
Aerobic
aquatic
metabolism
half­
life
94.5
days
assumed
0.5
x
PRZM
aerobic
soil
metabolism
input
value
because
the
compound
is
stable
to
hydrolysis
and
no
aerobic
aquatic
metabolism
data
are
available
(
Guidance
for
Selecting
Input
Parameters
in
Modeling
the
Environmental
Fate
and
Transport
of
Pesticides;
Feb
2,
2002)

Anaerobic
aquatic
metabolism
half­
life
15
days
assumed
0.5
x
anaerobic
soil
metabolism
half­
life
multiplied
by
three
(
T1/
2
=
10
days,
MRID
41322802)
because
no
anaerobic
aquatic
metabolism
data
are
available
and
the
compound
is
stable
to
hydrolysis
(
Guidance
for
Selecting
Input
Parameters
in
Modeling
the
Environmental
Fate
and
Transport
of
Pesticides;
Feb
2,
2002)
1
 
The
maximum
number
of
applications
was
not
specified
on
the
product
label;
three
applications
were
selected
based
on
a
maximum
annual
rate
of
12
lb
a.
i./
acre
and
3.9
lb
a.
i./
acre
maximum
application
rate
per
event.
2
 
The
average
value
of
four
organic
carbon
partition
coefficient
values
(
i.
e.,
840,
700,
933,
and
1290)
was
used
3
 
Since
only
one
laboratory
t
1/
2
value
(
63
days)
was
available
as
a
model
input
value
of
t
1/
2
x
3
was
used
based
on
Guidance
for
Selecting
Input
Parameters
in
Modeling
the
Environmental
Fate
and
Transport
of
Pesticides;
Feb
2,
2002.

Table
3.
Additional
PRZM­
EXAM
Input
Parameters
for
Oryzalin
11
Parameters
Input
Value
and
Unit
Source
of
Info/
Reference
First
Application
Date
(
day­
month)
PA
Golf
Course
Turf
=
10­
03
OR
Christmas
Trees
=
15­
03
CA
Almonds
=
04­
01
NC
Apples
=
25­
03
FL
Citrus
=
01­
03
Assumed
based
on
crop
profile
and
planting
dates
data
from
the
PRZM
crop
scenarios
Rainfall
Data
(
Metfile)
Golf
Course
Turf
=
W14737.
dvf
Christmas
Trees
=
W24232.
dvf
Almonds
=
W23232.
dvf
Apples
=
W03812.
dvf
Citrus
=
W12842.
dvf
Application
Fraction
Golf
Course
Turf
(
granular)
=
1.0
0.99
all
broadcast
0.95
aerial
(
CA
almonds)
Guidance
for
Selecting
Input
Parameters
in
Modeling
the
Environmental
Fate
and
Transport
of
Pesticides;
Feb
2,
2002
Spray
Drift
Fraction
Golf
Course
Turf
(
granular)=
0
Christmas
Trees
=
0.064
Almonds
=
0.064
(
ground)
Almonds
=
0.16
(
aerial)
Apples
=
=
0.064
Citrus
=
0.64
Same
as
above
The
most
conservative
estimates
of
the
drinking
water
concentrations
for
human
health
dietary
risk
assessment
were
obtained
for
application
of
oryzalin
to
Florida
citrus
at
the
maximum
annual
application
rate
of
12
lb
a.
i./
acre,
applied
twice
at
6
lb
a.
i./
acre
with
a
60­
day
interval.
The
estimated
drinking
water
concentrations
for
all
other
uses
were
significantly
lower.

For
evaluating
acute
concerns,
the
highest
simulated
1
in
10
year
annual
peak
concentration
of
oryzalin
in
drinking
water
was
198
ppb
in
Florida
citrus
index
reservoir
scenario
adjusted
with
a
default
PCA
factor
of
0.87
in
the
absence
of
a
specific
PCA
value
for
citrus.
For
evaluating
chronic
non­
cancer
concerns,
the
simulated
1
in
10
year
annual
mean
concentration
of
oryzalin
in
drinking
water
was
determined
to
be
12.7
ppb.
For
evaluating
concerns
for
cancer,
the
36­
year
annual
mean
concentration
was
determined
to
be
9.2
ppb
in
the
same
scenario.
Table
4
presents
all
simulated
surface
water
concentrations
of
oryzalin
for
crop
and
non­
crop
uses
adjusted
for
a
default
PCA
factor
of
0.87.

Table
4.
Oryzalin
estimated
drinking
water
concentrations
from
surface
water
sources.

Scenario
Application
type
Estimated
Drinking
Water
Concentrations
(
ppb)

1
in
10
year
annual
peak1
in
10
year
annual
mean36
year
annual
mean
FL
citrus
broadcast
19812.79.2
CA
almonds
ground
aerial
101
93.410.4
10.75.1
6.4
NC
apples
broadcast
99.27.35.2
OR
Christmas
trees
direct
spray
15.31.41.1
PA
golf
course
turf
granular
broadcast
23.31.91.0
12
Assumptions
and
Uncertainties
EFED
conducted
Tier
II
modeling
of
three
crop­
and
two
non­
crop
uses
at
their
highest
proposed
label
rates.
Because
oryzalin
can
be
used
on
a
broad
spectrum
of
berries,
vine
and
orchard
crops
and
has
several
non­
crop
uses
in
some
regions
it
may
be
applied
to
multiple
crops
and
non­
crops
within
a
single
watershed.
In
general,
the
likelihood
that
multiple
crops
will
be
found
within
single
watersheds
where
oryzalin
is
used
is
unknown
and
therefore
specific
PCA
adjustment
factors
were
not
used
and
each
scenario
was
adjusted
with
the
default
PCA
of
0.87.
Potential
to
underestimate
environmental
concentrations
may
be
associated
with
the
application
of
the
default
PCA
when
uses
on
turf
grass
are
co­
located
with
the
other
non­
crop
uses
and
crop
uses.

Within
each
scenario
a
change
of
oryzalin
application
dates
or
rainfall
pattern
may
influence
the
modeling
results.
Oryzalin
application
dates
where
selected
based
on
each
crop
and
non­
crop
profile
and
their
planting
dates
from
the
PRZM
crop
scenarios.
In
some
instances
this
information
was
based
on
information
gathered
from
regional
Pesticide
Information
Offices
or
regional
Herbicide
scientists.

B.
Ground
Water
Assessment
According
to
the
McCall
classification
(
McCall
et
al.,
1980),
oryzalin
appears
to
be
mobile
in
sand
and
sandy
loam,
relatively
mobile
in
loam,
and
immobile
in
clay
loam.
Oryzalin
Kd
values
are
2.1,
4.9,
8.4,
and
12.9
L
kg
o.
c.­
1
(
MRID
41479802).
Under
some
environmental
conditions
oryzalin
may
reach
vulnerable
ground
water
resources.
Open
literature
data
suggests
that
oryzalin
would
be
most
mobile
in
coarse,
moist,
alkaline
soils
with
little
organic
matter
content
(
Jacques
and
Harvey,
1979a;
Helling,
1976).
In
a
field
dissipation
study,
oryzalin
generally
was
undetectable
and
always
less
than
detection
limits
(
ppm)
below
12
inches
of
soil
depth.
Oryzalin
degradates
were
not
monitored
in
the
field.
An
aged
soil
adsorption/
desorption
study
(
non­
guideline
study,
MRID
43433202)
indicates
that,
out
of
nine
oryzalin
degradates
studied,
at
least
three
are
potentially
very
mobile
to
mobile
depending
on
soil
type.
These
degradates
are
4­
hydroxy­
3,5­
dinitrosulfanilamide
(
OR­
20;
K
d
=
0.56­
6.38
L/
kg),
2­
ethyl­
7­
nitro­
1­
propyl­
1H­
benzimidazole­
5­
sulfonamide
3­
oxide
(
UN­
2;
K
d
=
0.89­
4.52
L/
kg),
and
the
unidentified
[
14C]
compound
UN­
3,
with
a
K
d
ranging
from
1.50­
4.85
L/
kg
except
12.19
L/
kg
in
the
sand
soil.
Another
adsorption/
desorption
study
conducted
with
OR­
20
degradate
also
confirmed
that,
according
to
McCall
classification,
OR­
20
is
very
mobile
with
Koc
values
ranging
from
23.41
to
47.69
(
MRID
43433201).
The
drinking
water
modeling
was
conducted
for
parent
oryzalin
only.

The
SCI­
GROW
screening
model
was
used
to
estimate
ground
water
concentrations
of
oryzalin.
The
model
estimates
the
upper
bound
ground
water
concentrations
of
pesticides
likely
to
occur
when
the
pesticide
is
used
at
the
maximum
allowable
rate
in
areas
where
ground
water
is
particularly
vulnerable
to
contamination.
Table
5
lists
the
input
parameters
used
to
model
concentrations
of
oryzalin
in
ground
water.

Table
5.
SCI­
GROW
Input
Parameters
for
Oryzalin
Parameter
13
Input
Value
and
Units
Source
of
Info/
Reference
Maximum
Single
Application
Rate
Golf
Course
Turf
=
2
lb.
ai/
acre
Christmas
Trees
=
4
lb.
ai/
acre
Almonds
=
6
lb.
ai/
acre
Apples
=
6
lb.
ai/
acre
Citrus
=
6
lb.
ai/
acre
Product
Labels:
TURF
PRIDE
12­
00­
12
w/
SURFLAN;
EPA
Reg.
No.
035512­
00029
SURFLAN
A.
S.;
EPA
Reg.
No.
062719­
00112
SURFLAN
DF;
EPA
Reg.
No.
062719­
00138
SURFLAN
DF;
EPA
Reg.
No.
062719­
00138
SURFLAN
A.
S.;
EPA
Reg.
No.
062719­
00112
Max
Number
of
Applications
per
year
Golf
Course
Turf
=
3
All
Other
=
2
Product
labels
as
above
Partition
Coefficient
Normalized
to
Organic
Carbon
Content
1
­
Koc
887
L
kg
o.
c.­
1
MRID
41479802
(
GLN
163­
1)

Aerobic
Soil
Metabolism
t1/
2
63
days
MRID
41322801
(
GLN
162­
1)
1
 
the
median
of
four
K
oc
values
(
840,
700,
933,
1290)
was
used
The
highest
estimated
concentration
of
oryzalin
in
drinking
water
from
shallow
ground
water
sources
is
0.93
µ
g/
L
for
application
on
almonds,
apples,
and
citrus
at
6
lb
a.
i./
acre
applied
2
times
per
year.
This
concentration
may
be
considered
as
both
the
acute
and
chronic
upper
bound
value
for
use
in
the
human
health
risk
assessment.

Assumptions
and
Uncertainties
SCI­
GROW
was
developed
using
K
oc
values
ranging
from
32­
180
L/
Kg.
Extrapolation
beyond
these
values
further
increases
the
uncertainty
of
the
ground
water
EECs.
The
K
oc
input
value
for
oryzalin
was
887
L/
kg
o.
c.
Given
that
the
K
oc
of
oryzalin
is
outside
the
range
of
the
K
oc
values
used
to
develop
SCI­
GROW,
there
is
uncertainty
regarding
the
estimated
ground
water
concentrations
such
that
the
model
may
overestimate
concentrations.

Some
of
oryzalin's
degradates
appear
to
be
much
more
mobile
than
the
parent
and
therefore,
may
have
the
potential
to
reach
ground
water
resources.
In
particular,
degradate
4­
hydroxy­
3,5­
dinitrosulfanilamide,
appears
to
be
moderately
persistent
and
very
mobile,
and
has
the
potential
to
reach
ground
water
resources
via
leaching
in
all
soil
types
and
under
all
conditions.
Oryzalin
degradates
were
not
monitored
in
field
studies.
The
drinking
water
environmental
concentration
14
estimates
were
performed
only
for
the
parent.
If
human
toxicological
concerns
are
determined
to
be
associated
with
any
of
the
mobile
oryzalin
degradates,
a
drinking
water
assessment
would
need
to
be
conducted
for
the
degradate
of
concern.
15
VI.
REFERENCES
McCall
P.
J.,
R.
L.
Swann,
D.
A.
Laskowski,
S.
M.
Unger,
S.
A.
Vrona,.
and
H.
J.
Dishburger.
Estimation
of
Chemical
Mobility
in
Soil
from
Liquid
chromatographic
Retention
Times.
1980
Bull.
Environ.
Contam.
Toxicol.
24,
pp190­
195.
16
Appendix
I
Drinking
Water
Output
File
 
Surface
Water
Sources
PRZM/
EXAMS
output
file
for
Oryzalin
stored
as
oryzalin.
out
Chemical:
oryzalin
PRZM
environment:
FLcitrusC.
txt
modified
Satday,
12
October
2002
at
16:
39:
50
EXAMS
environment:
ir298.
exv
modified
Thuday,
29
August
2002
at
15:
34:
12
Metfile:
w12842.
dvf
modified
Wedday,
3
July
2002
at
09:
04:
28
Water
segment
concentrations
(
ppb)

Year
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
1961
42.59
38.45
23.56
13.78
10.85
5.664
1962
36.18
31.95
21.77
13.41
11.23
6.968
1963
64.7
57.04
44.95
29.42
21.33
7.975
1964
132
117
66.21
37.36
34.57
14.62
1965
93.36
82.6
56.86
35.65
28.45
9.163
1966
126
117
66.25
39.17
29.85
9.338
1967
69.64
61.92
37.68
30.63
25.75
8.222
1968
83.86
74.02
43.59
35.59
26.85
9.193
1969
137
122
79.16
45.43
38.25
14.6
1970
68.82
60.93
42.29
20.44
17.42
7.859
1971
221
195
109
48.16
36.71
13.11
1972
98.09
86.57
47.39
31.95
29.65
10.18
1973
77.82
69.15
39.62
20.19
15.51
8.393
1974
264
233
132
62.12
43.69
13.28
1975
115
102
65.75
41.78
30.48
10.32
1976
228
205
119
65.24
47.13
13.49
1977
20.73
18.28
10.85
9.257
8.883
3.782
1978
38.98
34.52
23.98
16.91
13.27
5.485
1979
856
764
438
193
134
37.65
1980
66.4
58.82
34.1
24.85
22.62
8.726
1981
96.5
85.19
57.88
30.72
22.91
9.22
1982
105
94.88
69.08
53.74
40.36
12.87
1983
156
138
83.86
47.18
35.52
14.03
1984
90.4
80.02
44.15
24.09
20.72
7.282
1985
135
119
70.03
40.03
33.66
11.28
1986
84.97
77.82
45.39
23.29
18.8
7.603
1987
111
98.36
59.72
39
35.86
12.93
1988
52.3
46.18
29.47
22.14
21.49
9.898
1989
55.25
49.24
34.82
23.62
19.1
6.26
1990
80.47
70.98
43.83
24.56
18.85
6.616
Sorted
results
Prob.
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
0.032258064516129
856
764
438
193
134
37.65
0.0645161290322581
264
233
132
65.24
47.13
14.62
0.0967741935483871
228
205
119
62.12
43.69
14.6
0.129032258064516
221
195
109
53.74
40.36
14.03
0.161290322580645
156
138
83.86
48.16
38.25
13.49
0.193548387096774
137
122
79.16
47.18
36.71
13.28
0.225806451612903
135
119
70.03
45.43
35.86
13.11
0.258064516129032
132
117
69.08
41.78
35.52
12.93
0.290322580645161
126
117
66.25
40.03
34.57
12.87
0.32258064516129
115
102
66.21
39.17
33.66
11.28
0.354838709677419
111
98.36
65.75
39
30.48
10.32
0.387096774193548
105
94.88
59.72
37.36
29.85
10.18
0.419354838709677
98.09
86.57
57.88
35.65
29.65
9.898
0.451612903225806
96.5
85.19
56.86
35.59
28.45
9.338
0.483870967741936
93.36
82.6
47.39
31.95
26.85
9.22
0.516129032258065
90.4
80.02
45.39
30.72
25.75
9.193
0.548387096774194
84.97
77.82
44.95
30.63
22.91
9.163
0.580645161290323
83.86
74.02
44.15
29.42
22.62
8.726
0.612903225806452
80.47
70.98
43.83
24.85
21.49
8.393
0.645161290322581
77.82
69.15
43.59
24.56
21.33
8.222
0.67741935483871
69.64
61.92
42.29
24.09
20.72
7.975
0.709677419354839
68.82
60.93
39.62
23.62
19.1
7.859
0.741935483870968
66.4
58.82
37.68
23.29
18.85
7.603
0.774193548387097
64.7
57.04
34.82
22.14
18.8
7.282
0.806451612903226
55.25
49.24
34.1
20.44
17.42
6.968
0.838709677419355
52.3
46.18
29.47
20.19
15.51
6.616
0.870967741935484
42.59
38.45
23.98
16.91
13.27
6.26
0.903225806451613
38.98
34.52
23.56
13.78
11.23
5.664
0.935483870967742
36.18
31.95
21.77
13.41
10.85
5.485
17
0.967741935483871
20.73
18.28
10.85
9.257
8.883
3.782
0.1
227.3
204
118
61.282
43.357
14.543
Average
of
yearly
averages:
10.5335666666667
Inputs
generated
by
pe3.
pl
1.2
­
15­
October­
2002
stored
as
oryzalin.
out
Chemical:
oryzalin
PRZM
environment:
CAalmondC.
txt
(
ground
application)
modified
Satday,
12
October
2002
at
16:
30:
38
EXAMS
environment:
ir298.
exv
modified
Thuday,
29
August
2002
at
15:
34:
12
Metfile:
w23232.
dvf
modified
Wedday,
3
July
2002
at
09:
04:
22
Water
segment
concentrations
(
ppb)

Year
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
1961
36.54
34.47
25.7
16.22
13.31
4.248
1962
116
104
61.57
27.51
18.79
7.596
1963
63.29
56.82
38.14
20.43
17.41
5.815
1964
69.03
68.27
56.72
29.77
22.45
6.135
1965
34.85
34.25
31.25
19.57
15.16
4.311
1966
15.96
15.68
14.28
9.368
8.076
2.879
1967
33.62
33.08
27.91
17.01
13.95
4.376
1968
26.15
24.99
23.55
15.15
12.1
3.355
1969
86.19
85.32
75.99
43.01
32.28
9.182
1970
61.03
60.27
57.09
32.24
24.1
7.314
1971
18.03
17.74
16.3
10.38
8.846
2.47
1972
16.45
16.17
14.73
9.43
8.06
2.489
1973
79.41
78.09
70.99
42.69
31.92
8.436
1974
17.5
17.19
16.44
10.63
8.949
2.615
1975
44.86
40.21
23.78
10.69
10.86
3.333
1976
15.57
15.29
13.92
8.737
7.566
2.323
1977
18.04
17.72
16.14
10.16
8.59
2.733
1978
115
113
104
64.86
46.74
12.29
1979
66.94
66.22
59.9
34.86
26.46
7.188
1980
62.18
61.39
57.19
33.27
25.12
6.672
1981
76.35
75.07
53.65
29.08
22.38
6.671
1982
221
217
198
125
90.62
25.76
1983
36.48
35.92
29.11
18.77
15.84
5.03
1984
15.81
15.53
14.16
8.896
7.706
2.179
1985
15.58
15.31
13.94
9.032
8.06
2.811
1986
27.11
26.56
21.68
16.63
13.37
3.647
1987
16.19
15.9
14.48
9.436
8.327
2.343
1988
27.77
27.31
24.13
14.75
11.8
3.94
1989
18.29
17.3
14.17
8.898
8.416
2.928
1990
136
135
124
67.14
48.47
13.48
Sorted
results
Prob.
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
0.032258064516129
221
217
198
125
90.62
25.76
0.0645161290322581
136
135
124
67.14
48.47
13.48
0.0967741935483871
116
113
104
64.86
46.74
12.29
0.129032258064516
115
104
75.99
43.01
32.28
9.182
0.161290322580645
86.19
85.32
70.99
42.69
31.92
8.436
0.193548387096774
79.41
78.09
61.57
34.86
26.46
7.596
0.225806451612903
76.35
75.07
59.9
33.27
25.12
7.314
0.258064516129032
69.03
68.27
57.19
32.24
24.1
7.188
0.290322580645161
66.94
66.22
57.09
29.77
22.45
6.672
0.32258064516129
63.29
61.39
56.72
29.08
22.38
6.671
0.354838709677419
62.18
60.27
53.65
27.51
18.79
6.135
0.387096774193548
61.03
56.82
38.14
20.43
17.41
5.815
0.419354838709677
44.86
40.21
31.25
19.57
15.84
5.03
0.451612903225806
36.54
35.92
29.11
18.77
15.16
4.376
0.483870967741936
36.48
34.47
27.91
17.01
13.95
4.311
0.516129032258065
34.85
34.25
25.7
16.63
13.37
4.248
0.548387096774194
33.62
33.08
24.13
16.22
13.31
3.94
0.580645161290323
27.77
27.31
23.78
15.15
12.1
3.647
0.612903225806452
27.11
26.56
23.55
14.75
11.8
3.355
0.645161290322581
26.15
24.99
21.68
10.69
10.86
3.333
0.67741935483871
18.29
17.74
16.44
10.63
8.949
2.928
0.709677419354839
18.04
17.72
16.3
10.38
8.846
2.879
0.741935483870968
18.03
17.3
16.14
10.16
8.59
2.811
0.774193548387097
17.5
17.19
14.73
9.436
8.416
2.733
0.806451612903226
16.45
16.17
14.48
9.43
8.327
2.615
0.838709677419355
16.19
15.9
14.28
9.368
8.076
2.489
0.870967741935484
15.96
15.68
14.17
9.032
8.06
2.47
0.903225806451613
15.81
15.53
14.16
8.898
8.06
2.343
18
0.935483870967742
15.58
15.31
13.94
8.896
7.706
2.323
0.967741935483871
15.57
15.29
13.92
8.737
7.566
2.179
0.1
115.9
112.1
101.199
62.675
45.294
11.9792
Average
of
yearly
averages:
5.8183
Inputs
generated
by
pe3.
pl
1.2
­
15­
October­
2002
stored
as
oryzalin.
out
Chemical:
oryzalin
PRZM
environment:
CAalmondC.
txt
(
Aerial
application)
modified
Satday,
12
October
2002
at
16:
30:
38
EXAMS
environment:
ir298.
exv
modified
Thuday,
29
August
2002
at
15:
34:
12
Metfile:
w23232.
dvf
modified
Wedday,
3
July
2002
at
09:
04:
22
Water
segment
concentrations
(
ppb)

Year
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
1961
34.45
32.91
26.33
18.87
13.4
6.339
1962
195
175
103
46.2
31.56
12.92
1963
31.33
29.34
25.05
18.36
12.97
6.133
1964
59.29
58.71
48.84
28.67
20.09
7.436
1965
41.57
40.86
37.32
23.66
16.53
6.397
1966
26.73
26.26
23.93
15.3
10.65
5.612
1967
34.76
34.48
29.94
20.19
14.13
5.733
1968
31.68
31.16
29.01
19.3
13.45
5.381
1969
71.74
70.62
62.87
37.81
27.07
9.394
1970
58.28
57.61
54.45
32.87
23.09
9.314
1971
29.32
28.85
26.51
16.88
11.85
4.848
1972
27.5
27.02
24.62
15.59
10.88
5.082
1973
64.25
63.2
58.33
36.18
25.48
8.612
1974
27.04
26.57
24.72
15.74
10.93
5.042
1975
26.76
26.29
23.97
15.08
10.5
4.449
1976
25.31
24.86
22.64
14.21
9.855
4.415
1977
30.15
29.62
26.98
17
11.84
5.449
1978
92.61
91.1
84.49
53.63
37.43
11.74
1979
61.72
60.98
55.21
33.58
23.4
8.084
1980
57.74
57.07
53.3
32.35
22.58
7.584
1981
72.39
71.2
52.17
31.02
22.05
9.1
1982
157
155
141
88.76
61.62
19.58
1983
36.36
35.82
29.43
21.37
15.21
7.2
1984
28.21
27.73
25.35
16
11.19
4.642
1985
25.34
24.89
22.67
14.41
10.02
5.318
1986
32.5
31.95
29.23
20.44
14.41
5.494
1987
26.41
25.95
23.63
15.09
10.61
4.57
1988
31.49
30.98
27.82
18.28
12.72
5.668
1989
29.61
26.39
23.19
14.57
10.11
5.643
1990
109
108
99.33
55.63
38.85
12.31
Sorted
results
Prob.
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
0.032258064516129
195
175
141
88.76
61.62
19.58
0.0645161290322581
157
155
103
55.63
38.85
12.92
0.0967741935483871
109
108
99.33
53.63
37.43
12.31
0.129032258064516
92.61
91.1
84.49
46.2
31.56
11.74
0.161290322580645
72.39
71.2
62.87
37.81
27.07
9.394
0.193548387096774
71.74
70.62
58.33
36.18
25.48
9.314
0.225806451612903
64.25
63.2
55.21
33.58
23.4
9.1
0.258064516129032
61.72
60.98
54.45
32.87
23.09
8.612
0.290322580645161
59.29
58.71
53.3
32.35
22.58
8.084
0.32258064516129
58.28
57.61
52.17
31.02
22.05
7.584
0.354838709677419
57.74
57.07
48.84
28.67
20.09
7.436
0.387096774193548
41.57
40.86
37.32
23.66
16.53
7.2
0.419354838709677
36.36
35.82
29.94
21.37
15.21
6.397
0.451612903225806
34.76
34.48
29.43
20.44
14.41
6.339
0.483870967741936
34.45
32.91
29.23
20.19
14.13
6.133
0.516129032258065
32.5
31.95
29.01
19.3
13.45
5.733
0.548387096774194
31.68
31.16
27.82
18.87
13.4
5.668
0.580645161290323
31.49
30.98
26.98
18.36
12.97
5.643
0.612903225806452
31.33
29.62
26.51
18.28
12.72
5.612
0.645161290322581
30.15
29.34
26.33
17
11.85
5.494
0.67741935483871
29.61
28.85
25.35
16.88
11.84
5.449
0.709677419354839
29.32
27.73
25.05
16
11.19
5.381
0.741935483870968
28.21
27.02
24.72
15.74
10.93
5.318
0.774193548387097
27.5
26.57
24.62
15.59
10.88
5.082
0.806451612903226
27.04
26.39
23.97
15.3
10.65
5.042
0.838709677419355
26.76
26.29
23.93
15.09
10.61
4.848
0.870967741935484
26.73
26.26
23.63
15.08
10.5
4.642
19
0.903225806451613
26.41
25.95
23.19
14.57
10.11
4.57
0.935483870967742
25.34
24.89
22.67
14.41
10.02
4.449
0.967741935483871
25.31
24.86
22.64
14.21
9.855
4.415
0.1
107.361
106.31
97.846
52.887
36.843
12.253
Average
of
yearly
averages:
7.3163
Inputs
generated
by
pe3.
pl
1.2
­
15­
October­
2002
stored
as
oryzalin.
out
Chemical:
oryzalin
PRZM
environment:
NCappleC.
txt
modified
Satday,
12
October
2002
at
17:
09:
36
EXAMS
environment:
ir298.
exv
modified
Thuday,
29
August
2002
at
15:
34:
12
Metfile:
w03812.
dvf
modified
Wedday,
3
July
2002
at
09:
05:
50
Water
segment
concentrations
(
ppb)

Year
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
1965
121
108
64.28
28.98
25.32
7.34
1966
75.24
66.63
37.34
23.64
18.16
6.396
1967
91.71
81.07
45.21
24.74
19.82
6.186
1968
90.62
80.22
44.69
25.45
18.94
5.528
1969
51.37
45.4
25.18
15.9
13.14
5.387
1970
41.3
38.3
22.11
10.82
8.892
3.943
1971
56.6
50.12
31.85
17.71
13.23
3.977
1972
199
176
97.89
46.19
35.54
9.735
1973
54.83
48.78
29.85
21.32
19.31
6.926
1974
93.29
83
53.1
26.74
21.55
7.394
1975
68.14
61.02
34.62
20.4
18.5
5.228
1976
96.45
85.82
48.56
25.03
26.86
8.526
1977
103
91.5
62.86
29.8
24.14
8.37
1978
78.92
69.91
40.06
18.18
12.93
6.424
1979
71.16
64.19
43.79
22.78
17.18
5.655
1980
98.22
87.51
57.7
30.56
24.17
7.571
1981
71.34
63.53
35.99
17.18
15.05
4.195
1982
58.38
51.7
32.76
22.57
16.64
5.27
1983
75.42
67.12
46.05
23.62
17.7
5.294
1984
82.17
73.21
50.29
25.51
20.63
7.003
1985
35.95
31.8
17.75
8.968
8.362
3.565
1986
76.55
67.69
38.43
17.41
12.06
4.627
1987
111
98.63
56.67
29.29
20.42
6.502
1988
24.91
22.18
15.56
9.078
7.69
3.043
1989
85.05
75.75
48.58
24.32
20
5.683
1990
69.21
61.17
37.1
20.69
16.41
5.854
Sorted
results
Prob.
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
0.037037037037037
199
176
97.89
46.19
35.54
9.735
0.0740740740740741
121
108
64.28
30.56
26.86
8.526
0.111111111111111
111
98.63
62.86
29.8
25.32
8.37
0.148148148148148
103
91.5
57.7
29.29
24.17
7.571
0.185185185185185
98.22
87.51
56.67
28.98
24.14
7.394
0.222222222222222
96.45
85.82
53.1
26.74
21.55
7.34
0.259259259259259
93.29
83
50.29
25.51
20.63
7.003
0.296296296296296
91.71
81.07
48.58
25.45
20.42
6.926
0.333333333333333
90.62
80.22
48.56
25.03
20
6.502
0.37037037037037
85.05
75.75
46.05
24.74
19.82
6.424
0.407407407407407
82.17
73.21
45.21
24.32
19.31
6.396
0.444444444444444
78.92
69.91
44.69
23.64
18.94
6.186
0.481481481481481
76.55
67.69
43.79
23.62
18.5
5.854
0.518518518518518
75.42
67.12
40.06
22.78
18.16
5.683
0.555555555555556
75.24
66.63
38.43
22.57
17.7
5.655
0.592592592592593
71.34
64.19
37.34
21.32
17.18
5.528
0.62962962962963
71.16
63.53
37.1
20.69
16.64
5.387
0.666666666666667
69.21
61.17
35.99
20.4
16.41
5.294
0.703703703703704
68.14
61.02
34.62
18.18
15.05
5.27
0.740740740740741
58.38
51.7
32.76
17.71
13.23
5.228
0.777777777777778
56.6
50.12
31.85
17.41
13.14
4.627
0.814814814814815
54.83
48.78
29.85
17.18
12.93
4.195
0.851851851851852
51.37
45.4
25.18
15.9
12.06
3.977
0.888888888888889
41.3
38.3
22.11
10.82
8.892
3.943
0.925925925925926
35.95
31.8
17.75
9.078
8.362
3.565
0.962962962962963
24.91
22.18
15.56
8.968
7.69
3.043
0.1
114
101.441
63.286
30.028
25.782
8.4168
20
Average
of
yearly
averages:
5.98546153846154
Inputs
generated
by
pe3.
pl
1.2
­
15­
October­
2002
stored
as
oryzalin.
out
Chemical:
oryzalin
PRZM
environment:
ORXmasTreeC.
txt
modified
Satday,
12
October
2002
at
17:
23:
10
EXAMS
environment:
ir298.
exv
modified
Thuday,
29
August
2002
at
15:
34:
12
Metfile:
w24232.
dvf
modified
Wedday,
3
July
2002
at
09:
06:
10
Water
segment
concentrations
(
ppb)

Year
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
1961
10.22
9.124
5.457
2.481
3.017
0.8539
1962
26.16
24.6
15.01
8.111
6.854
1.994
1963
33.46
30.66
18.5
10.34
8.412
2.445
1964
10.21
9.11
5.264
2.335
2.925
0.9253
1965
10.39
9.279
5.332
2.602
3.118
1.131
1966
10.21
9.116
5.301
2.353
2.941
1.205
1967
10.21
9.115
5.29
2.349
2.937
1.07
1968
10.21
9.113
5.28
2.342
2.932
1.132
1969
10.2
9.107
5.251
3.544
2.919
1.3
1970
10.21
9.11
5.266
2.335
2.925
0.9299
1971
13.09
11.71
6.805
4.92
4.673
1.524
1972
12.48
11.14
7.079
3.255
3.587
1.097
1973
10.21
9.114
5.289
2.347
2.935
1.032
1974
11.56
10.59
7.862
4.434
4.346
1.362
1975
13.91
12.47
8.209
3.715
3.862
1.149
1976
10.3
9.195
6.692
3.173
3.491
0.9148
1977
10.2
9.106
5.255
2.327
2.919
0.9013
1978
17.8
15.88
9.115
4.011
3.984
1.181
1979
10.93
9.745
5.557
2.752
2.938
1.324
1980
10.47
9.353
5.379
3.275
3.568
1.154
1981
10.37
9.26
5.345
2.936
3.4
1.384
1982
10.31
9.206
5.289
2.572
3.09
0.9549
1983
15.51
14.04
8.942
5.476
5.05
1.467
1984
10.87
9.705
5.581
3.248
3.577
1.088
1985
11.48
10.36
5.913
4.332
3.779
1.351
1986
10.2
9.109
5.259
2.332
2.922
0.851
1987
13.17
11.7
6.581
2.825
3.152
1.648
1988
10.24
9.143
5.645
2.555
3.081
1.108
1989
10.09
9.411
5.542
2.456
3.01
1.165
1990
10.26
9.156
5.332
2.395
2.975
1.149
Sorted
results
Prob.
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
0.032258064516129
33.46
30.66
18.5
10.34
8.412
2.445
0.0645161290322581
26.16
24.6
15.01
8.111
6.854
1.994
0.0967741935483871
17.8
15.88
9.115
5.476
5.05
1.648
0.129032258064516
15.51
14.04
8.942
4.92
4.673
1.524
0.161290322580645
13.91
12.47
8.209
4.434
4.346
1.467
0.193548387096774
13.17
11.71
7.862
4.332
3.984
1.384
0.225806451612903
13.09
11.7
7.079
4.011
3.862
1.362
0.258064516129032
12.48
11.14
6.805
3.715
3.779
1.351
0.290322580645161
11.56
10.59
6.692
3.544
3.587
1.324
0.32258064516129
11.48
10.36
6.581
3.275
3.577
1.3
0.354838709677419
10.93
9.745
5.913
3.255
3.568
1.205
0.387096774193548
10.87
9.705
5.645
3.248
3.491
1.181
0.419354838709677
10.47
9.411
5.581
3.173
3.4
1.165
0.451612903225806
10.39
9.353
5.557
2.936
3.152
1.154
0.483870967741936
10.37
9.279
5.542
2.825
3.118
1.149
0.516129032258065
10.31
9.26
5.457
2.752
3.09
1.149
0.548387096774194
10.3
9.206
5.379
2.602
3.081
1.132
0.580645161290323
10.26
9.195
5.345
2.572
3.017
1.131
0.612903225806452
10.24
9.156
5.332
2.555
3.01
1.108
0.645161290322581
10.22
9.143
5.332
2.481
2.975
1.097
0.67741935483871
10.21
9.124
5.301
2.456
2.941
1.088
0.709677419354839
10.21
9.116
5.29
2.395
2.938
1.07
0.741935483870968
10.21
9.115
5.289
2.353
2.937
1.032
0.774193548387097
10.21
9.114
5.289
2.349
2.935
0.9549
0.806451612903226
10.21
9.113
5.28
2.347
2.932
0.9299
0.838709677419355
10.21
9.11
5.266
2.342
2.925
0.9253
0.870967741935484
10.2
9.11
5.264
2.335
2.925
0.9148
0.903225806451613
10.2
9.109
5.259
2.335
2.922
0.9013
0.935483870967742
10.2
9.107
5.255
2.332
2.919
0.8539
0.967741935483871
10.09
9.106
5.251
2.327
2.919
0.851
21
0.1
17.571
15.696
9.0977
5.4204
5.0123
1.6356
Average
of
yearly
averages:
1.22637
Inputs
generated
by
pe3.
pl
1.2
­
15­
October­
2002
stored
as
oryzalin.
out
Chemical:
oryzalin
PRZM
environment:
PAturfC.
txt
modified
Satday,
12
October
2002
at
18:
27:
02
EXAMS
environment:
ir298.
exv
modified
Thuday,
29
August
2002
at
16:
34:
12
Metfile:
w14737.
dvf
modified
Wedday,
3
July
2002
at
10:
06:
12
Water
segment
concentrations
(
ppb)

Year
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
1961
11.44
10.15
7.051
3.193
2.156
0.74
1962
10.81
9.675
5.648
2.581
2.246
1.202
1963
18.38
16.37
10.06
5.063
4.032
1.123
1964
3.077
2.753
1.731
1.047
0.7476
0.4486
1965
3.023
2.781
1.652
1.336
0.99
0.4187
1966
10.14
9.032
6.071
3.32
2.54
0.8485
1967
19.55
17.38
10.53
4.876
3.381
1.188
1968
6.143
5.499
3.199
2.22
1.995
0.712
1969
21.65
19.21
11.2
4.977
3.38
0.9335
1970
12.52
11.26
6.503
2.878
2.039
1.129
1971
10.9
9.712
5.805
5.154
4.13
1.489
1972
27.32
24.29
13.68
7.019
4.98
2.198
1973
19.63
17.45
9.789
4.213
4.469
1.756
1974
4.592
4.08
2.376
1.979
1.629
0.9372
1975
17.35
15.45
9.123
5.199
3.762
1.525
1976
12.05
10.97
6.201
4.64
3.998
1.315
1977
10.79
9.658
6.036
2.87
2.03
0.9035
1978
8.018
7.123
4.624
2.111
1.612
0.8701
1979
18.86
16.81
11.45
6.734
4.683
1.726
1980
3.477
3.112
2.379
1.21
0.8402
0.421
1981
2.287
2.04
1.41
0.9591
0.688
0.3134
1982
16.09
14.31
8.21
4.785
4.393
1.424
1983
4.539
4.059
2.962
1.948
1.362
0.8776
1984
7.974
7.08
4.232
2.744
2.188
1.072
1985
63.05
56.15
32.2
14.84
10.55
3.22
1986
5.298
4.971
2.935
1.698
1.321
0.5666
1987
57.02
50.78
29.16
13.12
9.589
2.849
1988
10.66
9.5
5.416
2.374
2.176
1.038
1989
13.5
12.03
7.067
3.597
2.476
1.117
1990
10.14
9.004
5.068
2.986
2.446
1.113
Sorted
results
Prob.
Peak
96
hr
21
Day
60
Day
90
Day
Yearly
0.032258064516129
63.05
56.15
32.2
14.84
10.55
3.22
0.0645161290322581
57.02
50.78
29.16
13.12
9.589
2.849
0.0967741935483871
27.32
24.29
13.68
7.019
4.98
2.198
0.129032258064516
21.65
19.21
11.45
6.734
4.683
1.756
0.161290322580645
19.63
17.45
11.2
5.199
4.469
1.726
0.193548387096774
19.55
17.38
10.53
5.154
4.393
1.525
0.225806451612903
18.86
16.81
10.06
5.063
4.13
1.489
0.258064516129032
18.38
16.37
9.789
4.977
4.032
1.424
0.290322580645161
17.35
15.45
9.123
4.876
3.998
1.315
0.32258064516129
16.09
14.31
8.21
4.785
3.762
1.202
0.354838709677419
13.5
12.03
7.067
4.64
3.381
1.188
0.387096774193548
12.52
11.26
7.051
4.213
3.38
1.129
0.419354838709677
12.05
10.97
6.503
3.597
2.54
1.123
0.451612903225806
11.44
10.15
6.201
3.32
2.476
1.117
0.483870967741936
10.9
9.712
6.071
3.193
2.446
1.113
0.516129032258065
10.81
9.675
6.036
2.986
2.246
1.072
0.548387096774194
10.79
9.658
5.805
2.878
2.188
1.038
0.580645161290323
10.66
9.5
5.648
2.87
2.176
0.9372
0.612903225806452
10.14
9.032
5.416
2.744
2.156
0.9335
0.645161290322581
10.14
9.004
5.068
2.581
2.039
0.9035
0.67741935483871
8.018
7.123
4.624
2.374
2.03
0.8776
0.709677419354839
7.974
7.08
4.232
2.22
1.995
0.8701
0.741935483870968
6.143
5.499
3.199
2.111
1.629
0.8485
0.774193548387097
5.298
4.971
2.962
1.979
1.612
0.74
0.806451612903226
4.592
4.08
2.935
1.948
1.362
0.712
0.838709677419355
4.539
4.059
2.379
1.698
1.321
0.5666
0.870967741935484
3.477
3.112
2.376
1.336
0.99
0.4486
0.903225806451613
3.077
2.781
1.731
1.21
0.8402
0.421
22
0.935483870967742
3.023
2.753
1.652
1.047
0.7476
0.4187
0.967741935483871
2.287
2.04
1.41
0.9591
0.688
0.3134
0.1
26.753
23.782
13.457
6.9905
4.9503
2.1538
Average
of
yearly
averages:
1.18249
Inputs
generated
by
pe3.
pl
1.2
­
15­
October­
2002
Appendix
II
Drinking
Water
Output
File
 
Ground
Water
Sources
PRZM/
EXAMS
output
file
for
Oryzalin
SCIGROW
VERSION
2.2:
NOVEMBER
1,
2001
RUN
No.
1
FOR
oryzalin
**
INPUT
VALUES
**
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
APP
RATE
APPS/
TOTAL/
SOIL
AEROBIC
SOIL
METAB
(
LBS/
AC)
YEAR
SEASON
KOC
HALFLIFE
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
6.000
2
12.000
887.0
63.00
GROUND­
WATER
SCREENING
CONCENTRATION
(
IN
UG/
L
­
PPB)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.926210
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
23
APPENDIX
III
The
Data
Evaluation
Records
for
the
2
soil
absorption
studies
(
MRIDs
43433201
and
43433202)
are
available
from
the
Oryzalin
Chemical
Review
Manager.
