UNITED STATES ENVIRONMENTAL PROTECTION 

AGENCY

WASHINGTON D.C., 20460

OFFICE OF 

CHEMICAL SAFETY 

AND 

POLLUTION 

PREVENTION

PC Code: 119011

DP Barcode: 372897

DATE: 3/16/2011

MEMORANDUM

SUBJECT: Flazasulfuron: Drinking Water Assessment for First Food Uses on citrus, 

grapes and sugarcane and new outdoor non-food uses on Christmas trees 

and industrial vegetation management

FROM: Andrew Shelby, Physical Scientist

Environmental Fate and Effects Divison/ERB6 (7507P)

THRU: Mark Corbin, Branch Chief

Environmental Fate and Effects Divison/ERB6 (7507P)

TO: Cassi Walls, 

Health Effects Division (7509P)

Linda Arrington, Risk Manager (RM 25)

Registration Division (7505P)

The Environmental Fate and Effects Division (EFED) of the Office of Pesticide Programs (OPP) 

has completed a Drinking Water Assessment for new use of flazasulfuron on citrus, grapes and 

sugarcane and new outdoor non-food uses on Christmas trees and industrial vegetation 

management. For all proposed new uses, the proposed maximum single application rate is 0.045 

lb ai/A and the maximum seasonal application rate is 0.15 lb ai/A. Uses on Christmas trees and 

non-crop land has no maximum seasonal application limitation on the current proposed label. 

However, the registrant is aware of this and is in the process of submitting labels with consistent 

annual application limitations of 0.15 lb ai/A per year across all uses. This assessment has been 

conducted assuming these rates will be on the final label. If they are not, the exposure levels 

from these uses maybe different than those presented here. Currently registered for uses in 

control of annual and perennial grasses, sedges, and broadleaf weeds on golf courses and other 

non-residential turf areas, this is the first food use petition associated with flazasulfuron. This

Tier II assessment, in accordance with the ROCKS memo (D386767), considers the major 

degradates as parent in a total toxic residue (TTR) approach. Toxicity data and acceptable 
environmental fate data is unavailable for flazasulfuron degradates. Submission of degradate 

toxicity and environmental fate data would reduce uncertainty in the TTR approach and could 

potentially reduce exposure. Given current uncertainty, the following degradates are included in 

the TTR approach:

DTPU N-[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-3-(trifluoromethyl)-2-

pyridinesulfonamide

DTPP 4,6-dimethoxy-N-[3-trifluoromethyl)-2-pyridinyl]-2-pyrimidinamine

HTPP 6-methoxy-2-[[3-trifluoromethyl)-2-pyridinyl]amino]-4-pyrimidinol

TPSA 3-(trifluoromethyl)-2-pyridinesulphonamide

ADMP 2-amino-4,6-dimethoxypyrimidine

2,3-GTF 3-trifluoromethyl-2-pyridylguanidine

Based on modeling results (SCIGROW), the maximum estimated groundwater exposure 

concentration for total toxic residues of flazasulfuron for new and expanded uses is 257 μg/L for 

acute and chronic exposure. The SCIGROW input and output files that produced these results 

are attached as Appendix B.

Based on modeling results (PRZM/EXAMS), the maximum estimated surface water exposure 

concentrations for total toxic residues of flazasulfuron for new and expanded uses are:

26.9 μg/L for the 1 in 10 year annual peak concentration 

4.67 μg/L for the 1-in-10 year annual average, and 

2.76 μg/L for the 30 year annual average 

These results were generated from the CA impervious scenario which represents new use for 

industrial vegetation management. The CA impervious scenario produced the highest EDWCs 

in comparison to other relevant scenarios. Other scenarios used for this Drinking Water 

Assessment include FL citrus, FL nursery, FL sugarcane, LA sugarcane, MI sugarcane, NJ 

nursery and TN nursery to represent agricultural uses on citrus, grapes, sugarcane and Christmas 

trees and CA rangeland, CA residential, CA right of way, CA turf, FL turf, impervious BSS, 

range BSS and right of way BSS to represent industrial vegetation management uses. The 

PRZM/EXAMS input and output files that produced these results are attached as Appendix A.

This DWA differs from previous DWAs on flazasulfuron and reports higher EDWCs because of 

the inclusion of nonextracted residues in metabolism studies. Nonextracted residues are likely 

to be parent flazasulfuron or degradates included as total toxic residues. Data characterizing 

adsorption/desorption behavior of degradates and metabolism studies with more rigorous 

extraction techniques would reduce uncertainty associated with nonextracted residues. 

Excluding nonextracted residues from half-life calculations reduces EDWCs by less than 1% to 

9% for scenarios resulting in highest crop and non-crop EDWCs (CA impervious and LA 

sugarcane). Assuming the Koc of flazasulfuron represents the mobility of all degradates reduces 

the acute and chronic groundwater EDWC by 94%. Adsorption/desorption and toxicity data for 

degradates would be of most use to reduce uncertainty with the TTR approach. 

No monitoring data is available for flazasulfuron.
Fate and Transport Characterization

The most significant degradation pathway for total toxic residues of flazasulfuron is photolysis 

(half-life = 34 days; MRID 46220950). Total toxic residues of flazasulfuron are relatively more 

persistent to metabolism with half-lives ranging from 385 days to 3,466 days (MRIDs 46220951, 

46220953, 46220954). Total toxic residues of flazasulfuron are stable to hydrolysis (MRID 

46220949). Parent flazasulfuron is mobile with a KD of 10 mL/g (MRID 46220955). It is not 

appropriate to use KOC to characterize the mobility of flazasulfuron because adsorption 

coefficients do not sufficiently correlate with soil organic carbon content. Degradates of 

flazasulfuron are considered to be mobile (FAO Classification). The lowest degradate 

adsorption coefficient estimated by EpiSuite is KOC = 10 mL/ g o.c. for ADMP. 

Drinking Water Exposure Modeling

Input parameters for the derivation of Tier II surface water concentrations and the Tier 1 

groundwater concentration are as follows:

Table 1. PRZM/EXAMS input parameter values for flazasulfuron. Use on citrus, grapes, 

sugarcane, Christmas trees and industrial vegetation management

PARAMETER (units) VALUE(S) SOURCE COMMENT

Application Rate (kg a.i./ha) 0.050 Proposed 

label.

Represents the maximum possible single 

application rate per crop season (year) for 

all uses. Equivalent to 0.045 lb a.i./A.

Number of Applications 3 + application of 

0.019 kg a.i./ha

Proposed 

label.

Represents the maximum possible 

applications per crop season (year) for each 

use. 4th application achieves maximum 

seasonal application rate.

Interval between Applications 

(days)

14 Proposed 

label.

Represents the minimum possible interval 

between applications per crop season (year) 

for each use.

Molecular weight (g/mol) 407.4 Product 

Chemistry

-

Henry’s Law Constant (atmm3

/mol)

1.91 x 10-6 Product 

Chemistry

-

Vapor Pressure (torr) 7.5 x 10-3 Product 

Chemistry

-

Solubility in Water @ 20 OC, 

(mg/L or ppm)

2100 Product 

Chemistry

–

Soil Partition Coefficient (mL/g) KOC = 10 EpiSuite Because acceptable degradate adsorption 

data is not available, the lowest modeled 

adsorption coefficient for flazasulfuron 

degradates was used to represent the 

mobility of total toxic residues (ADMP: 10 

mL/g o.c.). 
PARAMETER (units) VALUE(S) SOURCE COMMENT

CAM (Chemical Application 

Method)

1 Proposed 

label.

ground spray; pre-plant or pre-emergence, 

unincorporated

Depth of Incorporation (inches) 0 Proposed 

label.

–

Application efficiency (decimal) Ground spray: 

0.99 

Input

Parameter

Guidance.

Spray drift fraction (decimal) Ground spray: 

0.01

Input 

Parameter 

Guidance.

Percent Cropped Area (decimal) Citrus, Grapes 

Sugarcane, 

Christmas trees: 

0.87

Industrial 

Vegetation 

Management: No 

PCA

PCA 

guidance

National Default PCA used for agricultural 

uses

Application date (day/month) Emergence dates 

specified in 

PRZM scenario

Proposed 

label and 

PRZM 

scenarios.

Multiple application dates surrounding the 

emergence dates for highest agricultural and 

non-agricultural EDWCs were modeled also

Hydrolysis Half-life (days) Stable MRID: 

46220949

TTR included in estimation

Aqueous Photolysis Half-life @ 

pH 7 (days)

34 MRID: 

46220950

TTR included in half-life estimation. Study 

conducted only at pH 7. Half-life 

estimation is likely to vary at a range of 

pHs.

Aerobic Aquatic Metabolism Halflife (days)432 MRID: 

46220954

TTR and nonextracted residues included in 

half-life estimation. Represents the 90th

percentile confidence bound on the mean of 

two half-life values (range: 408 days and 

385 days). The study is supplemental due 

to unaccounted residues and unextracted 

residues >10% of applied by conclusion of 

study.

Anaerobic Aquatic Metabolism 

Half-life (days)

2598 MRID: 

46220953

TTR and nonextracted residues included in 

half-life estimation. 3X half-life due to 

single half-life value per Input Parameter 

Guidance
PARAMETER (units) VALUE(S) SOURCE COMMENT

Aerobic Soil Metabolism Half-life 

(days)

10398 MRID: 

46220951

TTR and nonextracted residues included in 

half-life estimation. 3X half-life due to 

single half-life value per Input Parameter 

Guidance. Study is supplemental due to 

study termination at 268 days, inadequate 

characterization of degradate formation 

decline and inadequate records of sample 

storage.

1 “Input Parameter Guidance” refers to Guidance for Selecting Input Parameters in Modeling the Environmental 

Fate and Transport of Pesticides; Version 2.1, October 22, 2009. 

Table 2. SCIGROW input parameter values for flazasulfuron. Use on citrus, grapes, 

sugarcane, Christmas trees and industrial vegetation management

PARAMETER (units) VALUE(S) SOURCE COMMENT

Maximum Application Rate (lb 

a.i./A)

0.045 Proposed label. –

Number of Applications per Year 3.36 Proposed label. Represents the maximum possible 

applications per crop season (year) for each 

use. 4th application achieves maximum 

seasonal application rate.

Organic Carbon Partition 

Coefficient (Koc; mL/g)

10 EpiSuite Because acceptable degradate adsorption 

data is not available, the lowest modeled 

adsorption coefficient for flazasulfuron 

degradates was used to represent the 

mobility of total toxic residues (ADMP: 10 

mL/g o.c.). 

Aerobic Soil Metabolism Half-life 

(days)

3466 MRID: 

46220951

TTR and nonextracted residues included in 

half-life estimation. Study is supplemental 

due to study termination at 268 days, 

inadequate characterization of degradate 

formation decline and inadequate records of 

sample storage.

Percent Crop Area (PCA) post-processing on surface water EDWCs are incorporated for food 

uses but not for the non-crop use, industrial vegetation management. The proposed label allows 

applications for industrial vegetation management to “uncultivated non agricultural areas 

including but not limited to airports, ditch banks, dry canals, highway, railroad and utility rightsof-way, industrial sites, manufacturing sites, storage areas and warehouse areas.” This use 

pattern is not captured in PCA estimates. No PCA adjustment is applied to the groundwater 

exposure concentration. Modeled estimates are as follows.
Table 3. Ranges of Tier II Estimated Drinking Water Concentrations (EDWCs) for 

surface water based on ground application of flazasulfuron to citrus, grapes, sugarcane 

and Christmas trees. 0.87 PCA applied

Crop Scenario 1-in-10 year Acute 

concentration (ppb)

1-in-10 year annual 

average

30-year annual 

average

CA grape 0.37 0.17 0.09

FL citrus 2.97 0.74 0.27

FL nursery 2.68 0.66 0.21

FL sugarcane 5.09 0.90 0.48

LA sugarcane 6.40 1.05 0.62

NJ nursery 2.67 0.63 0.26

TN nursery 2.79 0.69 0.28

Table 4. Ranges of Tier II Estimated Drinking Water Concentrations (EDWCs) for 

surface water based on ground application of flazasulfuron industrial vegetation 

management. No PCA applied.

Crop Scenario 1-in-10 year Acute 

concentration (ppb)

1-in-10 year annual 

average

30-year annual 

average

CA impervious 26.91 4.67 2.76

CA rangeland 2.37 0.573 0.417

CA residential 1.92 0.676 0.408

CA right of way 3.63 0.813 0.371

CA turf 2.26 0.866 0.479

FL turf 0.296 0.111 0.0623

impervious BSS 26.61 3.442 1.971

Range BSS 2.62 0.696 0.306

right of way BSS 6.16 1.37 0.629

1 – January 7 application date
Appendix A: Output files for PRZM/EXAMS scenarios producing highest EDWCs

CA impervious January 1 application

stored as CAimperviousHYD.out

Chemical: flazasulfuron

PRZM environment: CAImperviousRLF.txt modified Tueday, 26 August 2008 at 05:16:48

EXAMS environment: ir298.exv modified Tueday, 26 August 2008 at 05:14:08

Metfile: w23234.dvf modified Tueday, 26 August 2008 at 05:15:38

Water segment concentrations (ppb)

Year Peak 96 hr 21 Day60 Day90 DayYearly

1961 16.25 15.72 14.29 11.45 9.319 3.54

1962 12.86 12.56 10.91 6.712 5.053 1.693

1963 29.96 28.49 25.7 18.4 13.95 4.478

1964 5.27 5.103 4.846 4.225 3.898 1.926

1965 11.14 11.03 10.3 8.761 8.379 3.341

1966 26.88 26.22 22.1 16.75 14.79 7.425

1967 39.72 33.92 25.62 20.75 15.9 4.695

1968 21.17 19.77 18.29 15.03 12.34 5.223

1969 18.71 17.4 12.82 7.513 5.8 1.96

1970 9.147 8.06 6.004 5.256 4.736 2.217

1971 3.438 3.279 2.712 2.345 2.227 1.255

1972 6.042 5.926 5.644 5.247 4.788 2.284

1973 19.85 18.46 12.97 8.597 6.462 2.192

1974 15.55 15 13.16 11.69 9.741 3.34

1975 25.5 24.61 20.48 12.52 9.188 3.132

1976 7.711 7.486 6.709 5.285 4.735 2.267

1977 11.06 10.89 9.865 8.347 7.371 3.861

1978 8.968 7.974 5.752 4.748 3.783 1.149

1979 15.85 14.39 9.944 7.335 6.212 2.631

1980 10.49 9.647 6.455 4.822 4.086 1.705

1981 5.15 4.997 4.629 3.561 2.901 1.211

1982 8.35 7.895 6.267 3.732 3.331 1.021

1983 12.27 11.27 9.303 5.726 4.019 1.094

1984 8.424 8.304 7.656 6.313 5.852 2.749

1985 10.68 10.17 8.47 6.431 5.658 2.554

1986 13.61 12.93 9.12 6.693 4.861 1.433

1987 12.16 11.6 9.113 7.435 6.725 3.317

1988 8.417 8.133 7.761 7.456 7.019 3.211

1989 8.622 8.428 8.25 7.108 6.174 2.607

1990 8.496 8.185 7.428 6.893 6.412 3.168

Sorted results

Prob. Peak 96 hr 21 Day60 Day90 DayYearly

0.032258064516129 39.72 33.92 25.7 20.75 15.9 7.425
0.0645161290322581 29.96 28.49 25.62 18.4 14.79 5.223

0.0967741935483871 26.88 26.22 22.1 16.75 13.95 4.695

0.129032258064516 25.5 24.61 20.48 15.03 12.34 4.478

0.161290322580645 21.17 19.77 18.29 12.52 9.741 3.861

0.193548387096774 19.85 18.46 14.29 11.69 9.319 3.54

0.225806451612903 18.71 17.4 13.16 11.45 9.188 3.341

0.258064516129032 16.25 15.72 12.97 8.761 8.379 3.34

0.290322580645161 15.85 15 12.82 8.597 7.371 3.317

0.32258064516129 15.55 14.39 10.91 8.347 7.019 3.211

0.354838709677419 13.61 12.93 10.3 7.513 6.725 3.168

0.387096774193548 12.86 12.56 9.944 7.456 6.462 3.132

0.419354838709677 12.27 11.6 9.865 7.435 6.412 2.749

0.451612903225806 12.16 11.27 9.303 7.335 6.212 2.631

0.483870967741936 11.14 11.03 9.12 7.108 6.174 2.607

0.516129032258065 11.06 10.89 9.113 6.893 5.852 2.554

0.548387096774194 10.68 10.17 8.47 6.712 5.8 2.284

0.580645161290323 10.49 9.647 8.25 6.693 5.658 2.267

0.612903225806452 9.147 8.428 7.761 6.431 5.053 2.217

0.645161290322581 8.968 8.304 7.656 6.313 4.861 2.192

0.67741935483871 8.622 8.185 7.428 5.726 4.788 1.96

0.709677419354839 8.496 8.133 6.709 5.285 4.736 1.926

0.741935483870968 8.424 8.06 6.455 5.256 4.735 1.705

0.774193548387097 8.417 7.974 6.267 5.247 4.086 1.693

0.806451612903226 8.35 7.895 6.004 4.822 4.019 1.433

0.838709677419355 7.711 7.486 5.752 4.748 3.898 1.255

0.870967741935484 6.042 5.926 5.644 4.225 3.783 1.211

0.903225806451613 5.27 5.103 4.846 3.732 3.331 1.149

0.935483870967742 5.15 4.997 4.629 3.561 2.901 1.094

0.967741935483871 3.438 3.279 2.712 2.345 2.227 1.021

0.1 26.742 26.059 21.938 16.578 13.789 4.6733

Average of yearly averages: 2.75596666666667

Inputs generated by pe5.pl - Novemeber 2006

Data used for this run:

Output File: CAimperviousHYD

Metfile: w23234.dvf

PRZM scenario: CAImperviousRLF.txt

EXAMS environment file: ir298.exv

Chemical Name: flazasulfuron

Description Variable Name Value Units Comments

Molecular weight mwt 407.4 g/mol

Henry's Law Const. henry 1.91E-6 atm-m^3/mol

Vapor Pressure vapr 7.5E-3 torr

Solubility sol 2100 mg/L
Kd Kd mg/L

Koc Koc 10 mg/L

Photolysis half-life kdp 34 days Half-life

Aerobic Aquatic Metabolism kbacw 432 days Halfife

Anaerobic Aquatic Metabolism kbacs 2598 days Halfife

Aerobic Soil Metabolism asm 10398 days Halfife

Hydrolysis: pH 5 0 days Half-life

Hydrolysis: pH 7 0 days Half-life

Hydrolysis: pH 9 0 days Half-life

Method: CAM 1 integer See PRZM manual

Incorporation Depth: DEPI 0 cm

Application Rate: TAPP 0.050 kg/ha

Application Efficiency: APPEFF 0.99 fraction

Spray Drift DRFT 0.01 fraction of application rate applied to pond

Application Date Date 1-1 dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1 interval 14 days Set to 0 or delete line for single app.

app. rate 1 apprate0.05 kg/ha

Interval 2 interval 14 days Set to 0 or delete line for single app.

app. rate 2 apprate0.05 kg/ha

Interval 3 interval 14 days Set to 0 or delete line for single app.

app. rate 3 apprate0.018 kg/ha

Record 17: FILTRA

IPSCND 1

UPTKF

Record 18: PLVKRT

PLDKRT

FEXTRC 0.5

Flag for Index Res. Run IR Reservoir

Flag for runoff calc. RUNOFF none, monthly or total(average of entire run)

CA impervious January 2 application

stored as CAimperviousHYD12.out

Chemical: flazasulfuron

PRZM environment: CAImperviousRLF.txt modified Tueday, 26 August 2008 at 05:16:48

EXAMS environment: ir298.exv modified Tueday, 26 August 2008 at 05:14:08

Metfile: w23234.dvf modified Tueday, 26 August 2008 at 05:15:38

Water segment concentrations (ppb)

Year Peak 96 hr 21 Day60 Day90 DayYearly

1961 13.08 12.58 11.93 9.581 7.795 2.963

1962 12.83 12.54 10.88 7.346 5.619 1.961

1963 38.31 36.23 31.44 21.66 16.45 5.293

1964 5.81 5.626 5.334 4.66 4.299 2.128

1965 11.15 11.03 10.31 8.766 8.384 3.343

1966 18.07 17.4 15.07 11.77 10.46 5.423
1967 39.71 33.92 26.8 22.66 17.45 5.174

1968 18.72 17.48 16.23 13.36 11.08 4.715

1969 18.7 17.39 11.23 6.563 5.077 1.72

1970 10.14 8.935 7.562 6.528 5.9 2.769

1971 4.54 4.33 3.585 3.493 3.373 1.749

1972 6.098 5.98 5.694 5.292 4.831 2.308

1973 24.61 22.86 15.07 9.318 6.937 2.305

1974 15.55 15 13.16 11.66 9.763 3.363

1975 27.1 26.15 21.34 12.94 9.47 3.222

1976 7.719 7.494 6.715 5.291 4.741 2.269

1977 15.17 14.72 13.51 12.03 11.48 5.546

1978 12.58 11.49 7.339 5.421 4.209 1.223

1979 15.56 14.13 9.763 6.254 5.19 2.319

1980 10.99 10.09 6.774 4.194 3.43 1.577

1981 6.937 6.732 6.185 4.263 3.471 1.503

1982 8.524 8.06 6.4 4.224 3.616 1.093

1983 12.27 11.28 9.306 5.741 4.029 1.096

1984 6.567 6.486 5.991 4.885 4.297 2.053

1985 10.66 10.15 8.452 6.413 5.64 2.546

1986 11.56 10.62 7.733 5.915 4.322 1.288

1987 12.57 11.82 10.65 10.04 8.662 3.868

1988 11.88 11.26 9.4 8.712 8.452 3.889

1989 8.671 8.477 8.302 7.149 6.216 2.624

1990 10.38 10.06 9.387 8.729 7.935 3.695

Sorted results

Prob. Peak 96 hr 21 Day60 Day90 DayYearly

0.032258064516129 39.71 36.23 31.44 22.66 17.45 5.546

0.0645161290322581 38.31 33.92 26.8 21.66 16.45 5.423

0.0967741935483871 27.1 26.15 21.34 13.36 11.48 5.293

0.129032258064516 24.61 22.86 16.23 12.94 11.08 5.174

0.161290322580645 18.72 17.48 15.07 12.03 10.46 4.715

0.193548387096774 18.7 17.4 15.07 11.77 9.763 3.889

0.225806451612903 18.07 17.39 13.51 11.66 9.47 3.868

0.258064516129032 15.56 15 13.16 10.04 8.662 3.695

0.290322580645161 15.55 14.72 11.93 9.581 8.452 3.363

0.32258064516129 15.17 14.13 11.23 9.318 8.384 3.343

0.354838709677419 13.08 12.58 10.88 8.766 7.935 3.222

0.387096774193548 12.83 12.54 10.65 8.729 7.795 2.963

0.419354838709677 12.58 11.82 10.31 8.712 6.937 2.769

0.451612903225806 12.57 11.49 9.763 7.346 6.216 2.624

0.483870967741936 12.27 11.28 9.4 7.149 5.9 2.546

0.516129032258065 11.88 11.26 9.387 6.563 5.64 2.319

0.548387096774194 11.56 11.03 9.306 6.528 5.619 2.308

0.580645161290323 11.15 10.62 8.452 6.413 5.19 2.305

0.612903225806452 10.99 10.15 8.302 6.254 5.077 2.269
0.645161290322581 10.66 10.09 7.733 5.915 4.831 2.128

0.67741935483871 10.38 10.06 7.562 5.741 4.741 2.053

0.709677419354839 10.14 8.935 7.339 5.421 4.322 1.961

0.741935483870968 8.671 8.477 6.774 5.292 4.299 1.749

0.774193548387097 8.524 8.06 6.715 5.291 4.297 1.72

0.806451612903226 7.719 7.494 6.4 4.885 4.209 1.577

0.838709677419355 6.937 6.732 6.185 4.66 4.029 1.503

0.870967741935484 6.567 6.486 5.991 4.263 3.616 1.288

0.903225806451613 6.098 5.98 5.694 4.224 3.471 1.223

0.935483870967742 5.81 5.626 5.334 4.194 3.43 1.096

0.967741935483871 4.54 4.33 3.585 3.493 3.373 1.093

0.1 26.851 25.821 20.829 13.318 11.44 5.2811

Average of yearly averages: 2.83416666666667

Inputs generated by pe5.pl - Novemeber 2006

Data used for this run:

Output File: CAimperviousHYD12

Metfile: w23234.dvf

PRZM scenario: CAImperviousRLF.txt

EXAMS environment file: ir298.exv

Chemical Name: flazasulfuron

Description Variable Name Value Units Comments

Molecular weight mwt 407.4 g/mol

Henry's Law Const. henry 1.91E-6 atm-m^3/mol

Vapor Pressure vapr 7.5E-3 torr

Solubility sol 2100 mg/L

Kd Kd mg/L

Koc Koc 10 mg/L

Photolysis half-life kdp 34 days Half-life

Aerobic Aquatic Metabolism kbacw 432 days Halfife

Anaerobic Aquatic Metabolism kbacs 2598 days Halfife

Aerobic Soil Metabolism asm 10398 days Halfife

Hydrolysis: pH 5 0 days Half-life

Hydrolysis: pH 7 0 days Half-life

Hydrolysis: pH 9 0 days Half-life

Method: CAM 1 integer See PRZM manual

Incorporation Depth: DEPI 0 cm

Application Rate: TAPP 0.050 kg/ha

Application Efficiency: APPEFF 0.99 fraction

Spray Drift DRFT 0.01 fraction of application rate applied to pond

Application Date Date 2-1 dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1 interval 14 days Set to 0 or delete line for single app.

app. rate 1 apprate0.05 kg/ha

Interval 2 interval 14 days Set to 0 or delete line for single app.
app. rate 2 apprate0.05 kg/ha

Interval 3 interval 14 days Set to 0 or delete line for single app.

app. rate 3 apprate0.018 kg/ha

Record 17: FILTRA

IPSCND 1

UPTKF

Record 18: PLVKRT

PLDKRT

FEXTRC 0.5

Flag for Index Res. Run IR Reservoir

Flag for runoff calc. RUNOFF none, monthly or total(average of entire run)

Appendix B: Output files for SCIGROW producing the groundwater EDWC

SciGrow version 2.3

chemical:flazasulfuron

time is 3/ 9/2011 13:12:18

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

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

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

 0.045 3.4 0.151 1.00E+01 3466.0

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

groundwater screening cond (ppb) = 2.57E+02 

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