Document ID: EPA-HQ-OPP-2008-0885-0007
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2010-02-24T05:00Z

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C.  20460

OFFICE OF   

PREVENTION, PESTICIDES

AND TOXIC SUBSTANCES 

		PC Code No.:	 129034

DP Barcodes: D359097, 362612

		Date: July 24, 2009

SUBJECT:	Drinking Water Assessment for: (1) IR-4 Registration for
Flumioxazin to be used on Cucurbit Group 9, Leaf Petioles Subgroup 4B
and Hops, and (2) Registration for Flumioxazin to be Used in the Noncrop
Areas

TO:		Joanne Miller, RM 23 

		Barbara Madden, RM 05

		John Redden

		Registration Division (7505P)

FROM:	Larry Liu, Environmental Scientist, Ph.D.

		Environmental Fate and Effects Division (7507P)

THROUGH:	Mah Shamim, Ph.D., Branch Chief

Environmental Risk Branch V

Environmental Fate and Effects Division (7507P)

The previous drinking water assessment for use of flumioxazin on cotton,
almonds, grapes, Christmas trees, deciduous trees and container and
field grown ornamentals (completed on July 7, 2003) can be used for the
currently proposed uses of Chateau WDG and Broadstar Herbicides.  The
new uses include: (1) IR-4 Registration for Flumioxazin to be used on
Cucurbit Group 9, Leaf Petioles Subgroup 4B and Hops, and (2)
Registration for Flumioxazin in the Noncrop Areas.  The maximum single
application rates and the yearly/seasonal application rates for the
proposed uses are either lower than or equivalent to the rates used in
the drinking water assessment completed on July 17, 2003.  The minimum
application intervals for the proposed new uses are the same or longer
than the interval used in the drinking water assessment completed on
July 17, 2003.  Table 1 includes the application rates and numbers for
flumioxazin on Cucurbit Group 9, Leaf Petioles Subgroup 4B and Hops. 
Table 2 includes the application rates and numbers for flumioxazin in
the Noncrop Areas. 

\

Table 1.  Uses and Application Rates for Flumioxazin on Cucurbit Group
9, Leaf Petioles 

Subgroup 4B, and Hops in the IR4 Registration (Chateau WDG Herbicide).

Crop	Maximum single application rate (lb ai/A)	Maximum application
number per  season	Application interval

(days)	Maximum application rate per season 

(lb ai/A/season)	Application methods

Cucurbit Group 9

(such as cucumber)	0.10	1	-	0.10	Broadcast, band, aerial, chemigation

Leaf Petioles 

Subgroup 4B 

(such as celery) 	0.13	2	35	0.26	Broadcast, band, aerial, chemigation

Hops	0.19	1	-	0.19	Broadcast, band, aerial, chemigation

Table 2.  Uses and Application rates in the Noncrop Areas for
Flumioxazin Registration (Broadstar Herbicide).

Uses	Single application rate (lb ai/A)	Maximum application number per
season	Application interval

(days)	Maximum application rate per season 

(lb ai/A/season)	Application methods

Noncrop areas in apartment complexes, gravel surfaces, ground mats, golf
courses, office complexes, parks, parking areas, recreational sites,
schools, sidewalks and other similar sites*	0.375	2	56	0.750	Drop or
rotary type granular equipment

* Label also includes uses on “container, field or landscape grown
ornamental shrubs, trees, Christmas trees, ground covers, non-bearing
fruit and nut trees, vines, and bare ground non-crop areas”

The previous drinking water assessment on cotton, almonds, grapes,
Christmas trees, deciduous trees and container and field grown
ornamentals is attached.

	UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

	WASHINGTON, D.C.  20460

PC Code:  129034

MEMORANDUM:

Date:		July 7, 2003

SUBJECT:	Tier I Estimated Environmental Concentrations for Flumioxazin
and Its Degradates from the Use on cotton, almonds, grapes, Christmas
trees, deciduous trees and container and field grown ornamentals		

TO:		Joanne Miller, PM 23 

J. Stone, PM Team Reviewer

Registration Division

Doug Dotson

Health Effects Division 

FROM:	Larry Liu, Ph.D., Environmental Scientist

Environmental Risk Branch V

Environmental Fate and Effects Division (7507C)

THROUGH:	Mah Shamim, Ph.D., Branch Chief

Environmental Risk Branch V

Environmental Fate and Effects Division (7507C)

This document summarizes the Tier I Estimated Environmental
Concentrations (EECs) for flumioxazin under the use for cotton, almonds,
grapes, Christmas trees, deciduous trees and container and field grown
ornamentals.  The FIRST and SCI-GROW models were used to estimate the
concentrations of this chemical and  its degradates in surface water and
groundwater, respectively.  These values represent upper-bound estimates
of the concentrations that might be found in surface water and
groundwater due to the use of flumioxazin on cotton, almonds, grapes,
Christmas trees, deciduous trees and container and field grown
ornamentals.  It should be noted that: (1) flumioxazin water numbers
were generated from the models in which the Koc values used were
obtained from a column leaching study instead of the typical absorption
study; (2) 482-HA water numbers were generated from the models in which
the Koc values for THPA were used; (3) APF and THPA water numbers were
generated from the adsorption/desorption studies; and (4) the initial
residue levels for the parent and its degradates used in the models were
based on the 30-day results of the hydrolysis study .  Due to the rapid
hydrolysis rate of the parent compound, EFED acknowledged the difficulty
in obtaining adsorption coefficients from the batch equilibrium study. 
Due to the rapid dissipating of flumioxazin in the environment, EFED is
not concerned about the parent compound.   Results at pH 7 are presented
below: 

	

Peak Conc. in Surface Water	

Conc. in Groundwater

Flumioxazin	

1.03 ppb	

negligible

482-HA	

6.87 ppb	

45.27 ppb

APF	

26.46 ppb	

 2.66 ppb

THPA	

27.67 ppb	

182.28 ppb

Should the results of this assessment need further refinement, please
contact us as soon as possible so that we may schedule a Tier II
assessment.

Water Resource Assessment tc \l2 "Water Resource Assessment 

Flumioxazin is unlikely to contaminate surface water and groundwater. 
However, its hydrolysis degradates (482-HA, APF, and THPA) are more
persistent and mobile and they tend to reach surface water and
groundwater at much higher concentrations.  Fate studies show that
flumioxazin is relative mobile (average Koc = 557, note: Koc values were
estimated from a column leaching study), but non-persistent (hydrolysis
half-life at pH 7 = 1 day; aqueous photolysis half-life at pH 5 = 1 day;
soil aerobic metabolism half life = 14.7 days; aquatic anaerobic
metabolism half-life = 0.2 days).   Since hydrolysis appears to be the
major route of dissipation in the environment, EFED used the residue
levels detected at the end of hydrolysis as the input parameters for
modeling.  Table 1 listed the degradates identified and their relative
concentrations from the hydrolysis study.  Based on the relative
concentrations presented in Table 1 and the application rate of the
parent, the worst residue levels that could be found on the soil surface
were estimated (see Table 2).

Table 1.  Percentages of the applied radioactivity identified at the end
of 30-day hydrolysis study

Compound	

pH 5	

pH 7	

pH 9

	

% of the applied

Flumioxazin	

negligible	

  4.7	

negligible

482-HA	

negligible	

  9.3	

97.3

APF	

83.6	

80.0	

negligible

THPA	

95.4	

83.6	

negligible

Table 2.  Maximum amounts of flumioxazin and its degradates expected to
be on the soil surface after flumioxazin was applied at the maximum rate
of 0.383 lb ai/A/application (two applications per year with an
application interval of 30-60 days).  

Compound	

pH 5	

pH 7	

pH 9

	

lbs ai/A/application

Flumioxazin	

negligible	

0.019	

negligible

482-HA	

negligible	

0.038	

0.391

APF	

0.199	

0.192	

negligible

THPA	

0.176	

0.153	

negligible

The FIRST and SCI-GROW models were used to estimate the concentrations
of this chemical and  its degradates in surface water and groundwater,
respectively.  These values represent upper-bound estimates of the
concentrations that might be found in surface water and groundwater due
to the use of flumioxazin at the maximum application rate.  Tables 3 and
4 listed the residue concentrations in the surface water and
groundwater, respectively.

Table 3.  Surface water estimated environmental peak concentrations for
flumioxazin and its major degradates in various pH.

	

pH 5	

pH 7	

pH 9

Flumioxazin	

negligible	

1.03 ppb	

negligible

482-HA	

negligible	

6.87 ppb	

70.71 ppb

APF	

27.43 ppb	

26.46 ppb	

negligible

THPA	

31.83 ppb	

27.67 ppb	

negligible

Table 4.  Groundwater estimated environmental concentrations for
flumioxazin and its major degradates in various pH.

	

pH 5	

pH 7	

pH 9

Flumioxazin	

negligible	

negligible	

negligible

482-HA	

negligible	

45.27 ppb	

465.82 ppb

APF	

 2.76 ppb	

 2.66 ppb	

negligible

THPA	

209.68 ppb	

182.28 ppb	

negligible



Surface Water and Groundwater Input Parameters tc \l3 "Surface Water and
Groundwater Input Parameters 

Surface water concentrations of flumioxazin were estimated with FIRST. 
The estimates made with FIRST are intended here to represent drinking
water sources with significant turnover such that there is no
year-to-year accumulation.  Ground water concentrations were predicted
with SCI-GROW.  Input parameters for FIRST and SCI-GROW at pH 7 (Tables
5-8) were selected according to current EFED guidance.  The application
rates for flumioxazin for pH 5 and 9 can be found in Table 2.  It should
be noted that the worst cases were assumed for those input parameters
which no information were available (such as APF was assumed to be very
stable under aerobic soil metabolism conditions with a half-life of 999
days).  Since the intended use of FIRST in this particular simulation is
only to represent a water body with significant water turnover, only the
peak concentration has physical significance.  The averaged
concentrations reported in Appendix 1 do not account for the turnover
and thus are less physically meaningful.  The SCI-GROW output file is
located in Appendix 2.  

 Table 5. FIRST and SCI-GROW input parameters for flumioxazin at pH 7.

Parameter	

FIRST Values	

SCI-GROW Values

Application number per year	

2 	

2 

Application rate	

 0.019 lb ai/acre	

 0.019 lb ai/acre

Application type	

aerial	

pH 7 Hydrolysis half life	

1 day	

1 day

Photolysis half life	

1 day	

n/a

Aerobic soil metabolism half life	

23.4	

14.7 days (mean value)

Aerobic aquatic half life	

n/a	

n/a

Solubility	

1.8 ppm	

n/a

Koc*	

656 	

112

* Koc was estimated from a column leaching study instead of the
adsorption study.  Due to the rapid hydrolysis rate of the parent
compound, EFED acknowledged the difficulty in obtaining adsorption
coefficients from the batch equilibrium study. 

Table 6. FIRST and SCI-GROW input parameters for 482-HA at pH 7.

Parameter	

FIRST Values	

SCI-GROW Values

Application number per year	

2 	

2 

Application rate	

 0.038 lb ai/acre	

 0.038 lb ai/acre

Application type	

aerial	

pH 7 Hydrolysis half life	

stable	

stable

Photolysis half life	

stable	

n/a

Aerobic soil metabolism half life	

stable	

stable

Aerobic aquatic half life	

stable	

n/a

Solubility*	

10,000 ppm	

n/a

Koc** 	

13 	

13

*   No water solubility is available so 10,000 ppm was assumed.

** Koc for THPA was used for 482-HA

Table 7. FIRST and SCI-GROW input parameters for APF at pH 7.

Parameter	

FIRST Values	

SCI-GROW Values

Application number per year	

2 	

2 

Application rate	

 0.192 lb ai/acre	

 0.192 lb ai/acre

Application type	

aerial	

pH 7 Hydrolysis half life	

stable	

stable

Photolysis half life	

stable	

n/a

Aerobic soil metabolism half life	

stable	

stable

Aerobic aquatic half life	

stable	

n/a

Solubility*	

10,000 ppm	

n/a

Koc 	

201 	

201

*   No water solubility is available so 10,000 ppm was assumed.

Table 8. FIRST and SCI-GROW input parameters for THPA at pH 7.

Parameter	

FIRST Values	

SCI-GROW Values

Application number per year	

2 	

2 

Application rate	

 0.153 lb ai/acre	

 0.153 lb ai/acre

Application type	

aerial	

pH 7 Hydrolysis half life	

stable	

stable

Photolysis half life	

stable	

n/a

Aerobic soil metabolism half life	

stable	

stable

Aerobic aquatic half life	

stable	

n/a

Solubility*	

10,000 ppm	

n/a

Koc	

13 	

13

*   No water solubility is available so 10,000 ppm was assumed.

Drinking Water Recommendations

EFED has recommended that the Health Effects Division use the
concentrations presented in Table 9 for drinking water EECs. 

Table 9.  Estimated EECs for flumioxazin and its degradates in surface
water and groundwater at pH 7.

Compound	

Average 56-Day Conc. in  Surface Water	

Peak Conc. in Surface Water	

Conc. in Groundwater

Flumioxazin	

negligible	

1.03 ppb	

negligible

482-HA	

4.84 ppb	

6.87 ppb	

45.27 ppb

APF	

12.85 ppb	

26.46 ppb	

 2.66 ppb

THPA	

19.50 ppb	

27.67 ppb	

182.28 ppb



Appendix 1: FIRST for Environmental Fate Assessment

Background Information on FIRST:

FIRST is a new screening model designed to estimate the pesticide
concentrations found in water for use in drinking water assessments.  It
provides high-end values on the concentrations that might be found in a
small drinking water reservoir due to the use of pesticide.  Like
GENEEC, the model previously used for Tier I screening level, FIRST is a
single-event model (one run-off event), but can account for spray drift
from multiple applications.  FIRST uses a Drinking Water Reservoir
instead of a pond as the standard scenario.  The FIRST scenario includes
a 427 acres field immediately adjacent to a 13 acres reservoir,  9 feet
deep, with continuous flow (two turnovers per year).  The pond receives
a spray drift event from each application plus one runoff event.  The
runoff event moves a maximum of 8% of the applied pesticide into the
pond.  This amount can be reduced due to degradation on field and the
effect of binding to soil.  Spray drift is equal to 6.4% of the applied
concentration from the ground spray application and 16% for aerial
applications.

FIRST also makes adjustments for the percent crop area. While FIRST
assumes that the entire watershed would not be treated, the use of a PCA
is still a screen because it represents the highest percentage of crop
cover of any large watershed in the US, and it assumes that the entire
crop is being treated.  Various other conservative assumptions of FIRST
include the use of a small drinking water reservoir surrounded by a
runoff-prone watershed, the use of the maximum use rate, no buffer zone,
and a single large rainfall.

FIRST Results at various pHs:

PH 5

   RUN No.  11 FOR APF              ON   Christmas tree   * INPUT VALUES
* 

  
------------------------------------------------------------------------
---------------------------------------

    RATE (#/AC)   No.APPS &     SOIL  SOLUBIL  APPL TYPE      %CROPPED 
INCORP

     ONE(MULT)   INTERVAL    Koc    (PPM )       (%DRIFT)          AREA 
          (IN)

  
------------------------------------------------------------------------
---------------------------------------

   .199(   .398)       2          30        201.0  10000.0     
AERIAL(16.0)   87.0                .0

   FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

  
------------------------------------------------------------------------
-----------------------------------------------

   METABOLIC  DAYS UNTIL     HYDROLYSIS   PHOTOLYSIS   METABOLIC 
COMBINED

    (FIELD)          RAIN/RUNOFF   (RESERVOIR)   (RES.-EFF)       
(RESER.)         (RESER.) 

  
------------------------------------------------------------------------
-----------------------------------------------

    .00                   2       N/A             .00-                  
  .00                      .00                     .00

   UNTREATED WATER CONC (MICROGRAMS/LITER (PPB))    Ver 1.0 AUG 1, 2001

  
------------------------------------------------------------------------
-----------------

        PEAK DAY  (ACUTE)      ANNUAL AVERAGE (CHRONIC)      

        CONCENTRATION        CONCENTRATION            

  
------------------------------------------------------------------------
-----------------

             27.426                                       13.322

************************************************************************
*******************

pH 5

   RUN No.   2 FOR THPA             ON   Christmas tree   * INPUT VALUES
* 

    
------------------------------------------------------------------------
---------------------------------------

    RATE (#/AC)   No.APPS &     SOIL  SOLUBIL  APPL TYPE      %CROPPED 
INCORP

     ONE(MULT)   INTERVAL    Koc    (PPM )       (%DRIFT)          AREA 
          (IN)

  
------------------------------------------------------------------------
--------------------------------------- 

   .176(   .352)       2     30             13.0   10000.0     
AERIAL(16.0)   87.0                  .0

   FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

  
------------------------------------------------------------------------
-----------------------------------------------

   METABOLIC  DAYS UNTIL     HYDROLYSIS   PHOTOLYSIS   METABOLIC 
COMBINED

    (FIELD)          RAIN/RUNOFF   (RESERVOIR)   (RES.-EFF)       
(RESER.)         (RESER.) 

  
------------------------------------------------------------------------
-----------------------------------------------

   .00                    2     N/A                .00-                 
  .00                      .00                    .00

   UNTREATED WATER CONC (MICROGRAMS/LITER (PPB))    Ver 1.0 AUG 1, 2001

  
------------------------------------------------------------------------
-----------------

        PEAK DAY  (ACUTE)      ANNUAL AVERAGE (CHRONIC)      

        CONCENTRATION          CONCENTRATION            

  
------------------------------------------------------------------------
-----------------

       

             31.830                                  22.436

************************************************************************
********************

pH 7

   RUN No.   3 FOR Flumioxazin      ON   Christmas tree   * INPUT VALUES
* 

   
------------------------------------------------------------------------
---------------------------------------

    RATE (#/AC)   No.APPS &     SOIL  SOLUBIL  APPL TYPE      %CROPPED 
INCORP

     ONE(MULT)   INTERVAL    Koc    (PPM )       (%DRIFT)          AREA 
          (IN)

  
------------------------------------------------------------------------
---------------------------------------

   .019(   .027)       2    30              656.0   1.8            
AERIAL(16.0)    87.0               .0

  

   FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

  
------------------------------------------------------------------------
-----------------------------------------------

   METABOLIC  DAYS UNTIL     HYDROLYSIS   PHOTOLYSIS   METABOLIC 
COMBINED

    (FIELD)          RAIN/RUNOFF   (RESERVOIR)   (RES.-EFF)       
(RESER.)         (RESER.) 

  
------------------------------------------------------------------------
-----------------------------------------------

     23.40               2                          1.00                
    1.00-  124.00     .00                    .99

   UNTREATED WATER CONC (MICROGRAMS/LITER (PPB))    Ver 1.0 AUG 1, 2001

  
------------------------------------------------------------------------
--------------

        PEAK DAY  (ACUTE)      ANNUAL AVERAGE (CHRONIC)      

          CONCENTRATION             CONCENTRATION            

  
------------------------------------------------------------------------
--------------

              1.034                                      .004

************************************************************************
************

pH 7

   RUN No.   4 FOR 482-HA           ON   Christmas tree    * INPUT
VALUES * 

   
------------------------------------------------------------------------
---------------------------------------

    RATE (#/AC)   No.APPS &     SOIL  SOLUBIL  APPL TYPE      %CROPPED 
INCORP

    ONE(MULT)    INTERVAL    Koc    (PPM )       (%DRIFT)          AREA 
          (IN)

  
------------------------------------------------------------------------
---------------------------------------

  .038(   .076)        2     30             13.0   10000.0     
AERIAL(16.0)    87.0                .0

  

   FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

  
------------------------------------------------------------------------
-----------------------------------------------

   METABOLIC  DAYS UNTIL     HYDROLYSIS   PHOTOLYSIS   METABOLIC 
COMBINED

    (FIELD)          RAIN/RUNOFF   (RESERVOIR)   (RES.-EFF)       
(RESER.)         (RESER.) 

  
------------------------------------------------------------------------
-----------------------------------------------

           .00            2          N/A          .00-                  
   .00                      .00                    .00

   UNTREATED WATER CONC (MICROGRAMS/LITER (PPB))    Ver 1.0 AUG 1, 2001

  
------------------------------------------------------------------------
---------------------

        PEAK DAY  (ACUTE)      ANNUAL AVERAGE (CHRONIC)      

          CONCENTRATION             CONCENTRATION            

  
------------------------------------------------------------------------
---------------------

              6.872                      4.844

************************************************************************
*************

pH 7

   RUN No.   4 FOR APF           ON   Christmas tree    * INPUT VALUES *

   
------------------------------------------------------------------------
---------------------------------------

    RATE (#/AC)   No.APPS &     SOIL  SOLUBIL  APPL TYPE      %CROPPED 
INCORP

    ONE(MULT)    INTERVAL    Koc    (PPM )       (%DRIFT)          AREA 
          (IN)

  
------------------------------------------------------------------------
---------------------------------------

   .192(   .384)         2  30              201.0  10000.0     
AERIAL(16.0)   87.0                .0

   FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

  
------------------------------------------------------------------------
-----------------------------------------------

   METABOLIC  DAYS UNTIL     HYDROLYSIS   PHOTOLYSIS   METABOLIC 
COMBINED

    (FIELD)          RAIN/RUNOFF   (RESERVOIR)   (RES.-EFF)       
(RESER.)         (RESER.) 

  
------------------------------------------------------------------------
-----------------------------------------------

       .00                  2          N/A         .00-                 
  .00                      .00                     .00

   UNTREATED WATER CONC (MICROGRAMS/LITER (PPB))    Ver 1.0 AUG 1, 2001

  
------------------------------------------------------------------------
--------------

        PEAK DAY  (ACUTE)      ANNUAL AVERAGE (CHRONIC)      

          CONCENTRATION             CONCENTRATION            

  
------------------------------------------------------------------------
--------------

             26.461                                    12.854

************************************************************************
*********

pH 7

   RUN No.   6 FOR THPA             ON   Christmas tree     * INPUT
VALUES * 

    
------------------------------------------------------------------------
---------------------------------------

    RATE (#/AC)   No.APPS &     SOIL  SOLUBIL  APPL TYPE      %CROPPED 
INCORP

    ONE(MULT)    INTERVAL    Koc    (PPM )       (%DRIFT)          AREA 
          (IN)

  
------------------------------------------------------------------------
---------------------------------------  

   .153(   .306)       2  30                13.0   10000.0      
AERIAL(16.0)   87.0                .0

   FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

  
------------------------------------------------------------------------
-----------------------------------------------

   METABOLIC  DAYS UNTIL     HYDROLYSIS   PHOTOLYSIS   METABOLIC 
COMBINED

    (FIELD)          RAIN/RUNOFF   (RESERVOIR)   (RES.-EFF)       
(RESER.)         (RESER.) 

  
------------------------------------------------------------------------
-----------------------------------------------

       .00                2      N/A             .00 -                  
 .00                       .00                     .00

   UNTREATED WATER CONC (MICROGRAMS/LITER (PPB))    Ver 1.0 AUG 1, 2001

  
------------------------------------------------------------------------
-------------

        PEAK DAY  (ACUTE)      ANNUAL AVERAGE (CHRONIC)      

          CONCENTRATION             CONCENTRATION            

  
------------------------------------------------------------------------
--------------

             27.670                     19.504

************************************************************************
****************

pH 9

   RUN No.   7 FOR 482-HA           ON   Christmas tree    * INPUT
VALUES * 

    
------------------------------------------------------------------------
---------------------------------------

    RATE (#/AC)   No.APPS &     SOIL  SOLUBIL  APPL TYPE      %CROPPED 
INCORP

    ONE(MULT)    INTERVAL    Koc    (PPM )       (%DRIFT)          AREA 
          (IN)

  
------------------------------------------------------------------------
---------------------------------------  

   .391(   .782)        2    30             13.0   10000.0     
AERIAL(16.0)    87.0               .0

   FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

  
------------------------------------------------------------------------
-----------------------------------------------

   METABOLIC  DAYS UNTIL     HYDROLYSIS   PHOTOLYSIS   METABOLIC 
COMBINED

    (FIELD)          RAIN/RUNOFF   (RESERVOIR)   (RES.-EFF)       
(RESER.)         (RESER.) 

  
------------------------------------------------------------------------
-----------------------------------------------

       .00                2      N/A              .00-                  
  .00                      .00                    .00

   UNTREATED WATER CONC (MICROGRAMS/LITER (PPB))    Ver 1.0 AUG 1, 2001

  
------------------------------------------------------------------------
-------------------------

        PEAK DAY  (ACUTE)      ANNUAL AVERAGE (CHRONIC)      

          CONCENTRATION             CONCENTRATION            

  
------------------------------------------------------------------------
-------------------------

             70.713                                      49.843

 
------------------------------------------------------------------------
-------------------------- 



Appendix 2:  SCI-ROW for Environmental Fate Assessment

Background Information on SCI-GROW:

SCI-GROW provides a ground water screening exposure value to be used in
determining the potential risk to human health from drinking water
contaminated with the pesticide. Since the SCI-GROW concentrations are
likely to be approached in only a very small percentage of drinking
water sources, i.e., highly vulnerable aquifers, it is not appropriate
to use SCI-GROW concentrations for national or regional exposure
estimates.

SCI-GROW estimates likely ground water concentrations if the pesticide
is used at the maximum allowable rate in areas where ground water is
exceptionally vulnerable to contamination. In most cases, a large
majority of the use area will have ground water that is less vulnerable
to contamination that the areas used to derive the SCI-GROW estimate. 

SCI-GROW Results at pH 5

VERSION 2.2: NOVEMBER 1, 2001                

   RUN No.  11 FOR APF                 ** INPUT VALUES **       

  
------------------------------------------------------------------------
----------------------  

    APP RATE   APPS/   TOTAL/     SOIL   AEROBIC SOIL METAB  

    (LBS/AC)     YEAR    SEASON   KOC    HALFLIFE (DAYS)    

  
------------------------------------------------------------------------
-----------------------   

       .199             2            .398           201.0         
999.00

   GROUND-WATER SCREENING CONCENTRATION (IN UG/L - PPB)  

   --------------------------------------------------------  

                           2.756142

   --------------------------------------------------------   

   RUN No.  12 FOR THPA                  ** INPUT VALUES **       

  
------------------------------------------------------------------------
------------------------  

    APP RATE   APPS/   TOTAL/     SOIL   AEROBIC SOIL METAB  

    (LBS/AC)     YEAR    SEASON   KOC    HALFLIFE (DAYS)    

  
------------------------------------------------------------------------
------------------------   

       .176               2           .352          13.0              
999.00

   GROUND-WATER SCREENING CONCENTRATION (IN UG/L - PPB)  

   --------------------------------------------------------  

                         209.676900

   --------------------------------------------------------   

 

 SCIGROW Results at pH 7 :         

   RUN No.   1 FOR flumioxazin         ** INPUT VALUES **       

  
------------------------------------------------------------------------
-----------------------------  

    APP RATE   APPS/   TOTAL/     SOIL   AEROBIC SOIL METAB  

    (LBS/AC)     YEAR    SEASON   KOC     HALFLIFE (DAYS)    

  
------------------------------------------------------------------------
-----------------------------   

       .019                2           .038         112.0             
14.70

   GROUND-WATER SCREENING CONCENTRATION (IN UG/L - PPB)  

   --------------------------------------------------------  

                            .00317

   --------------------------------------------------------   

   RUN No.   2 FOR 482-HA              ** INPUT VALUES **       

  
------------------------------------------------------------------------
------------------------------  

    APP RATE   APPS/   TOTAL/     SOIL   AEROBIC SOIL METAB  

    (LBS/AC)     YEAR    SEASON   KOC    HALFLIFE (DAYS)    

  
------------------------------------------------------------------------
-------------------------------   

       .038                2           .076         13.0            
999.00

   GROUND-WATER SCREENING CONCENTRATION (IN UG/L - PPB)  

   --------------------------------------------------------  

                          45.271150

   --------------------------------------------------------   

   RUN No.   3 FOR APF                 ** INPUT VALUES **       

  
------------------------------------------------------------------------
-------------------------------  

    APP RATE   APPS/   TOTAL/     SOIL   AEROBIC SOIL METAB  

    (LBS/AC)     YEAR    SEASON   KOC    HALFLIFE (DAYS)    

  
------------------------------------------------------------------------
--------------------------------   

       .192               2            .384        201.0           
999.00

   GROUND-WATER SCREENING CONCENTRATION (IN UG/L - PPB)  

   --------------------------------------------------------  

                           2.659193

   --------------------------------------------------------   

   RUN No.   4 FOR THPA                ** INPUT VALUES **       

  ------------------------------------------------
--------------------------------------------------------  

    APP RATE   APPS/   TOTAL/     SOIL   AEROBIC SOIL METAB  

    (LBS/AC)     YEAR    SEASON   KOC    HALFLIFE (DAYS)    

  
------------------------------------------------------------------------
-------------------------------   

       .153               2           .306         13.0           999.00

   GROUND-WATER SCREENING CONCENTRATION (IN UG/L - PPB)  

   --------------------------------------------------------  

                         182.275900

   --------------------------------------------------------   

 

SCI-GROW Results at pH 9

   

RUN No.  21 FOR 482-HA              ** INPUT VALUES **       

  
------------------------------------------------------------------------
--------------------  

    APP RATE   APPS/   TOTAL/     SOIL   AEROBIC SOIL METAB  

    (LBS/AC)     YEAR    SEASON   KOC    HALFLIFE (DAYS)    

  
------------------------------------------------------------------------
--------------------   

       .391               2           .782          13.0                
999.00

   GROUND-WATER SCREENING CONCENTRATION (IN UG/L - PPB)  

   --------------------------------------------------------  

                         465.816300

   --------------------------------------------------------   

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