UN IT E D ST A

TES ENV IR ONMENTAL P R OTECTION AGENCY
WAS lll GTO D

. C.

. 20460

OHICFOr PR!: Vf'\;TIO'I. PESTICIDES AND TOXIC SU B STt \ NC!-S

PC Co d e: 11 1401
DP B arcode: D4 25755

Sep t ember 14

, 2015



### MEMORANDUM

SUBJECT: Drinking Wa ter Assessment for Profenofo s for R eg i s tration R ev i e w.



### TO: C hri st ina Scheltema, Chem i ca l R ev i ew Manager
K e ll y S h e rman , Branch Chief



### FROM: Ri sk Management and Implem e nt at i on Bran c h 3
Pesticide R e -e va lu ation Di vis i on (7508P )

AND

Sarah Levy

, Di etary Assessor C h arles Smith

, Branch Chief
Ri sk Assessme nt Branch 1 Health Effects Di v isi on (7509P)

Mich e ll e Colle tti

, C h e mi st 

### J

. 

# I;// ' 

# f 

# c 17 

# 0 er 

# l,y 

# I 

# I<

William P. Eckel, Ph.D.

, Senior Science Adv i so r

# /W~ 

# . e-f-1 / 1

E n viro nm e nt al Ri sk Branch 6
E n v ironmental Fate and Effects Di v i sio n (7507P)



### THROUGH: Moni caWa it

, RAPL

## ~**W~** C\/IL\-/\5

Mark Corb in

, Branch C hi ef 

### tJ 1 1 

# 0 I. ) 

# g

Env ir o nm e ntal Risk Branch 6

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## ~-\ ')"
Env ironm e nt a l Fate and Effec t s Di v i sion ( 7507P)

Th i s memo descr i bes the Tier 2 estimated drinking water conce ntrati o n s (EDWCs) for

pr ofe n ofos i n surface wa ter and t he Ti e r 1 estimates of drinking water conce ntrations 

### in ground

water for the r eg i s tration r eview of profenofo s for human health ri sk assessme nt. Th e

r ecom m e nd e d E DW Cs for profenofos are based on the o nl y c urr e ntl y r eg i s t ered use site

, cotton,

w h ich i s g r own in severa l s tates. The modeled u se pattern and l oca ti o n s represent values that

are ex p ec t e d to b e excee ded only rarely (o n ce every t e n yea r s) in drinking water in watersheds2 

### whe re cotton is grown. T he perce nt crop ped area (PCA) for cotton, 0. 21

, was used for a national assessment.

Th e recommended EDWCs modeled using the Surface Water Concentration Calculator (SWCC) for the surface water drinking water exposure assessment for registration review are 5.92 

### μ g/L (ppb) for the peak concentration, 0.283 

### μ g/L for the annual mean concentration, and an overall mean concentration of 0.167 

### μ g/L . The highest peak concentration

, the highest annual, and overall mean values occurred with th e Texas cotton organophosphate scenario

. This scenario, set in Milam Count y, Texas, between Dallas and Houston, was developed for the OP cumulative human health risk assessment.

T he highest estimated ground water concentration modeled using PRZM

- GW is 2.51


### μ g/L over 30 years and 16 

### μ g/L over 100 years. All PRZM

- GW scenarios are set in vulnerable soil and weather combinations. B reakthrough to the aquifer was not observed over either a 30 year period or a 100 year period

. The highest peak concentration values for ground water occurred with the Florida ci trus scenario

, which stands as a surrogate for scenarios of cotton grown in Georgia or North Florida

.

Table 1. Estimated Drinking Water Concentrations (EDWC) of profenofos residues for
cotton in an Index Reservoir with the SWCC model

. The simulations used the maximum labeled number ( 10) of applications and application rate (0.5 lb. a.i./A /application), and a maximum seasonal application rate ( 5 lb. a

. i

. / A ). The concentrations have been adjusted with the Percent Crop ped Area (PCA) of 0

. 21 for cotton for a national assessment.

1

- in

- 10 year Profenofos Concentration (μg/L) Concentration (μg/L)

Scenario

- State Crop Peak Annual Mean Overall Annual Mean

CA

- Cotton 0. 5 27 0.0382 0.0365

MS

– Cotton 4.87 0.214 0.113

NC

- Cotton 4.43 0.206 0.0945

TX

– Cotton 5.92 0.283 0.167

1 The bold values represent the recommend EDWCs to be use in the drinking water assessment.
2 The SWCC model res ults can be found in Appendix 1



### Use Characterization

Profenofos is an insecticide/miticide belonging to the organophosphate class of pesticides. The toxicity of organophosphates is based on the inhibition of the enzyme acetylcholinesterase which cleaves the neurotransmitter acetylcholine. Inhibition of acetylcholinesterase by organophosphate insecticides interferes with proper neurotransmission in cholinergic neurosynapses and neuromuscular junctions. Profenofos is registered for use only on cotton and can be applied by enclosed cab ground application equipment to control cotton bollworm, tobacco budworm, certain other listed insects, and mites. Aerial application is not permitted. The maximum single application rate of profenofos is 0.5 lb. a.i . / A with a minimum3 

### application interval of 5 days and a season al maximum application rate of 5 lb. a.i . / A (maximum of 10 application s per season)

. Profenofos application is prohibited within 100 ft. of any body of water . A spray drift percentage was calculated in AgDrift (v 2.1.1) using a high boom setting and fine to medium drop let size distribution (EFED, 2001)

.

Table 2 Maximum Application Parameters for Profenofos
Application

Use site Maximum Rate (lbs a

. i

. /acre) Interval (days) Date Maximum Annual (lbs a

. i

. /acre)

Cotton 0.5 lbs a

. i

. /acre 5 days (10 applications) First application date on
emergence in SWCC ( June 1 ) 5 lbs a

. i

. /acre



### Chemical Name : O

- (4

- bromo

- 2

- chlorophenyl) O

- ethyl S

- propyl phosphorothioate

Environmental Fate and Transport:

Based on available laboratory studies, p rofenofos degrades primarily by microbial metabolism as well as the abiotic process of hydrolysis . The half

- lives used in this assessment were recalculated from original study results using the cu rrently accepted model PestDF (EFED

, 2014)

. Aerobic and anaerobic soil metabolism half

- lives are similar, 2.3 and 2.1 days respectively. Degradation due to hydrolysis varies with pH, with half

- lives ranging from 107

- 475 days for acidic (pH 5) waters, 24 .4

- 69.9 days for waters with neutral pH (pH 7), and 0.3 2

- 0.43 days for alkaline waters (pH 9). The half

- life of profenofos, under anaerobic aquatic cond itions, due to metabolism is 3.8 days at 25 °C. The values of the photolysis half

- life were compared to the h ydrolysis half

- lives at pH 5 (MRIDs 41627309, 41939001 ). The dark corrected photolysis half

- life was found to be 266 days.

The predominant degradate of profenofos observed in laboratory studies (including hydrolysis, photolysis, and metabolism) was 4

- br omo

- 2

- chlorophenol, which was formed by hydrolysis of the organophosphate group from the phenyl ring of profenofos. Also formed in equimolar parts with t his degradate is O

- ethyl

- S

- propyl phosphor o thioate. According to the July 28, 1995 memo “Profenofos. Outcome of the 7/18/95 Meeting of the HED Metabolism Committee ” (H ED , 1995)

, t he parent compound, profenofos, is the only residue of concern for the human health risk assessment

.
An available laboratory study indicates that profenofos has a slight mobility potential to leach in soils. The organic carbon partition coefficient (K OC 

### ) was determined to be 3890 (MRID 48612101)

. No scientifically valid studies are available to define the volatility of profenofos. The estimated vapor pressure is given a s 9.30 x 10

- 7 

### torr (British Crop Protection Council, 1997)

. The environmental fate data and values used in the drinking water mo deling are summarized in Table 3

.4 

### Table 3 . Summary of environmental fate parameters for profenofos and values used for modeling ( SWCC and PRZM

- GW ).

Parameter Range Value Used in Model Source Molecular Weight 373.63 (g/mol) 373.63 (g/mol) Product chemistry Solubility in water 20 mg/L 20 mg/L IRED (USEPA 2000)

Vapor Pressure 9.30 x 10

- 7 torr 9.30 x 10

- 7 torr T he Pesticide Manual, 1997, p. 1006

Hydrolysis T 1⁄2 (at 25 ° C) 1 107

– 475 (pH 5)
24.4

– 69.9 (pH 7)
0.3 2

- 0.43 (pH 9) 69.9 days MRID 41627 309, 41939001

Aquatic Photolysis T 1⁄2 1 T 1⁄2 = 266 days 266 days MRID 41939002

Aerobic Soil Metabolism T 1⁄2 1 2.3 days @ 25 °C 6.9 days 2.3 days x 3 MRID 42334302 (EFED, 2009)
Ana erobic Soil Metabolism T 1⁄2 1 2.1 days @ 25 ° C MRID 42334303

Water Column Metabolism T 1/2 1 13.8 days @ 25 °C

6.9 days x 2 (EFED, 2009)

Anaerobic Aquatic Metabolism, T 1⁄2 1 3.8 days @ 25 °C 3.8 days @ 25 MRID 42218101

Sorption Koc 3890 (mL/g) 3890 (mL/g) MRID 48612101 Application Efficiency 0.99 ground spray (EFED, 2009)

Foliar Half

- Life 35 days (EFED, 2009) Spray Drift % 0.0042 AgDrift (v 2.1.1)

Henry’s Law Constant 2.38 x 10

- 7 atm

- m 3
mol

- 1 2.38 x 10

- 7 atm

- m 3
mol

- 1 (EFED, 2008)

Diffusion in Air 0.032980 cm 2 /d (EFED, 2003)
Enthalpy 8.1 kcal/mol (EFED, 2003)

1 Half

- lives were recalculated using PestDF (EFED, 2014)



### Monitoring Data

Monitoring data for profenofos were downloaded from the Water Quality Portal database ( http://waterqualitydata.us/ ) on June 04 , 2015. The Water Quality Portal integrates data from the USGS National Water Information System (NWIS), EPA’s STORET data warehouse, and USDA ARS STEWARDS platform . A total of 2,336 records were retrieved for the analysis of profenofos. The data covered a time period from 1993 to March 2015. Twenty eight states were represented in the data set including (states that are bold represent cotton growing states): AZ

, C A

, AL

, AR , CO, CT, FL

, GA , HI, IN, KY, MA, MD, MI, MN, MO

, NC , NE, NV, NY, OH, OR, PA, TX , VA, WA, and WI. All of the samples were non

- detects.5 

### Data from California Department of Pesticide Regulation was also accessed for this assessment on June 08, 2015 . The sampling period for which profenofos was monitored in surface and ground water was 2002

- 2005, and 2007

- 2009. A total of 735 records were retrieved, all of which were non

- detects with a limit of quantitation of 0.05 ppb. The CADPR surface water dat abase can be found at: http://www.cdpr.ca.gov/docs/emon/surfwtr/surfcont.htm

.
Groundwater data provided by the Texas Commission of Environmental Quality (TCEQ) to the EPA returned 245 results. A total of 245 results were retrieved and occurred in the y e ars 1987, 1988, 1990, and 2003. All of the results were non

- detects with a limit of quantitation of 0.0059 ppb.

None of the data listed above is a result of sampling targeted to profenofos use . T hat coupled with a less robust sample frequency would suggest that the monitoring results are probably missing the peak concentrations of profenofos , if and when it is used

. Mallampalli (2014) reports that profenofos use has declined sharply since 1998, thus it is less like ly that it would be detected in ambient monitoring.

Simulation Modeling

Surface Water

- Drinking Water

For Tier 2 surface water assessments , the Surface Water Concentration Calculator (SWCC) version 1.106 (EFED, 2014) , was used to estimate environmental fate and transport of the active ingredient profenofos in surface waters. The Tier 2 assessment reports the EDWC s for profenofos that are expected once every ten years. The estimates are generated using 30

- years of me teorological data, encompassing the years from 1961 to 1990. For further information on these models see: http://www.epa.gov/oppefed1/models/water/index.htm

.

The profenofos concentrations simulated by SWCC assume that 100% of the watershed is planted to the simulated crop. The raw SWCC concentrations (output) are then multiplied by the PCA (percent crop ped area) factor for cotton to account for the less than 100% coverage by the crop in a watershed large enough to support a drinking water facility. The SWCC output concentrations multiplied by the PCA are the estimated drinkin g water concentration s (EDWC). PCAs are the maximum proportion of a drinking water basin that might be plant ed with a specific crop (EFED, 2014)

. The PCA (percent crop area) for cotton was determined to be 0. 21

.

Scenario Selection

The only registered use of profenofos is for cotton. To calculate the EDWC s , all four modeling scenarios relevant to cotton were selected for use in SWCC. The se scenarios ( CAcotton, TXCotton OP, MScotton, and NCcotton ) are representative of the Western, Southern, and Eastern growing regions respectively. Generally, off

- site transport is controlled by spray drift in the drier growing regions, such as California. Run

- off also contributes in wetter areas such as the east.6 

### Profenofos is labeled for application only by ground spray . Up to 10 profenofos applications may be applied per season with a maximum single application rate of 0.5 lbs a.i ./ A and annual maximum application rate of 5 lb s a

. i

. /acre . The minimum reapplication interval is 5 days.

Ground Water

Tier 1 ground water EDWCs for profenofos , resulting from its use on cotton were derived with PRZM

- GW (Pesticide Root Zone Model for Groundwater, vers ion 1.0, August 31, 2012)

. PRZM

- GW accounts for pesticide fate in the crop root zone by simulating pesticide transport and degradation through the soil profile after a pesticide is applied to an agricultural field. PRZM

GW permits the assessment of multipl e years of pesticide application (up to 100 years) on a single site. Six standard scenarios, each representing a different region known to be vulnerable to groundwater contamination, are available for use with PRZM

- GW for risk assessment
purposes

. T he WI sands scenario was excluded from modeling of profenofos for ground water EDWCs since it is outside the US cotton growing region and therefore not relevant

. PRZM

- GW output values represent pesticide concentrations in a vulnerable groundwater supply that is located directly beneath a rural agricultural field. For this reason, use of a PCA adjustment factor is not appropriate for PRZM

- GW

. For further information on th is model see: http://www.epa.gov/oppefed1/models/water/index.htm

.

PRZM

- GW estimates likely ground water concentrations if the pesticide is used at the maximum allowable application rate in areas where ground water is exceptionally vulnerab le to contamination (Table 4 ). The profenofos estimated drinking water concentration s were modeled for each scenario over 30 years and 100 years, and can be found in Table 4

. The application rate and interval used in the model for the 30 year period can be found in Table 2

, and the environmental fate values used as inputs for modeling are listed in Table 3

. An extended weather file was used in all five of the PRZM

- GW scenarios to simulate 100 years of

use because breakthrough was unobserved in each of the scenar ios over a 30 year period. Breakthrough, for the purposes of PRZM

- GW, is defi ned as the point at which the full concentration of the active ingredient applied to the crop is observed to reach the groundwater layer. The PRZM

- GW model is limited to 500 total applications of the active ingredient over the entire time series of the mo del run. Thus, the number of applications for the 100 year modeling period was condensed to 5 applications per season with twice the maximum application rate, 1 lb. a.i./A, per application so as not to exceed the capacity of PRZM

- GW. Breakthrough of prof enofos to the groundwater was incomplete over 100 years of application in all five of the scenarios.

Table 4. Estimated Ground Water Concentrations of profenofos residues calculat ed using the PRZM

- GW model over 30 years and 100 years

.

Scenario Daily Peak (μg/L) Post Breakthrough Average (μg/L) Average Breakthrough Time (Days)

NJ/DE

– 30 years 0.00106 Incomplete Incomplete

NJ/DE

– 100 years 6.38 Incomplete7 FL

– Citrus

– 30 years 2.51 Incomplete Incomplete

FL

– Citrus

– 100 years 16 Incomplete Incomplete

FL

– Potato

– 30 years 8.79 x 10

- 5 Incomplete Incomplete

FL

– Potato

– 100 years 1.96 Incomplete Incomplete

GA

– 30 years 3.03 x 10

- 9 Incomplete Incomplete

GA

– 100 years 0.0266 Incomplete Incomplete

NC

– 30 years 0.0193 Incomplete Incomplete

NC

– 100 years 0.478 Incomplete Incomplete
Abbreviations: NJ/DE=Delmarva Sweet Corn; NC=NC cotton; GA=Georgia Peanuts

1

. The PRZM

- GW model results can be found in Appendix 2.8 

### CITATIONS

Baris, Reubin, et al. 2012. Guidance for Using PRZM

- GW in Drinking Water Exposure Assessments. Arlington : US EPA, 2012. Guidance.

Bradbury, Steven. 2007. Tier II Drinking Water Exposure Assessment Guidance. Office of
Pesticide Programs : US EPA, 2007. Guidance.
British Crop Protect ion Council. 1997. The Pesticide Manual Eleventh Edition. Surrey, UK : British Crop Protection Council, 1997.

EFED. 2001. A User's Guide for AgDRIFT 2.01: A Tiered Approach for the Assessment of Spray
Drift of Pesticides. Environmental Fate and Effects Div ision : US EPA, Office of
Pesticide Programs, 2001. User Manual.

EFED 2003. Presentation to Environmental Fate Tech Team, February 13, 2003. Environmental

Fate and Effects Division : US EPA, Office of Pesticide Programs, 2003.

EFED 2008. Registration Revie w: Preliminary Problem Formulation for Ecological Risk,
Environmental Fate, Endangered Species, and Drinking Water Assessment for
Profenofos. Environmental Fate and Effects Division : US EPA, Office of Pesticide
Programs, 2008. 348151.

EFED 2009. Guidance for Selecting Input Parameters in Modeling the Environmentl Fate and
Transport of Pesticides (Version 2.1). Environmental Fate and Effects Division : US
EPA, Office of Pesticide Programs, 2009. Guidance.

EFED 2014

. Development of Community Water System Dri nking Water Intake Percent Cropped
Area Adjustment Factors for use in Drinking Water Exposure Assessments: 2014 Update

. Environmental Fate and Effects Division : US EPA, Office of Pesticide Programs, 2012.

Guidance.

EFED 2014. NAFTA Guidance to Calculate R epfresentative Half

- life Values and Characterizing
pesticide Degredation. Office of Pesticide Programs, Environmental Fate and Effects

Division : US EPA, 2014. Guidance.

EPA, US. 2000. Interim Registration Eligibility Decision (IRED): Profenofos. Washingto n,

D.C. : US EPA, Office of Pesticide Programs, 2000.
Fry, Meredith, et al. 2014. Surface Water Concentration Calculator User Manual.

Environmental Fate and Effects Division, Office of Pesticides : US EPA, 2014. User

Manual.9 

### Health Effects Division (HED) . 1995

. Profenofos. Outcome of the 7/18/95 Meeting of the HED
Metabolism Committee. Reregistration Case No. 2540. Chemical No. 111401.
Washington, D.C. : US EPA, Office of Pestic ide Programs, 1995. 21400 MARC.
Mallampalli, Nikhil et al. 2014. Profenofos : General Information on its Use and Alternatives to
Support Registration Review. August 19. 2014.10 

### Appendix 1

– SWCC Modeling Results : Summary of Water Modeling of Profenofos and the USEPA Standard Reservoir

Table 1. Estimated Environmental Concentrations (ppb) Profenofos from the CA cotton scenario

.

Peak (1

- in

- 10 yr) 2.51

4

- day Avg (1

- in

- 10 yr) 2.19

21

- day Avg (1

- in

- 10 yr) 1.77

60

- day Avg (1

- in

- 10 yr) 1.05

365

- day Avg (1

- in

- 10 yr) 0.182

Entire Simulation Mean 0.174

Table 2. Summary of Model Inputs for Profenofos.

Scenario CAcotton_WirrigSTD
Cropped Area Fraction 1.0
Koc (ml/g) 3890

Water Half

- Life (days) @ 25 °C 13.8

Benthic Half

- Life (days) @ 25 °C 3.8
Photolysis Half

- Life (days) @ 40 °Lat 266
Hydrolysis Half

- Life (days) 69.9

Soil Half

- Life (days) @ 25 °C 6.9

Foliar Half

- Life (days) 35

Molecular Wt 373.63
Vapor Pressure (torr) 9.3E

- 7
Solubility (mg/l) 20

Figure 1. Yearly Peak Concentrations11 Table 3 . Estimated Environmental Concentrations (ppb) for Profenofos for MS cotton scenario

.

Peak (1

- in

- 10 yr) 23.2

4

- day Avg (1

- in

- 10 yr) 18.8

21

- day Avg (1

- in

- 10 yr) 11.2

60

- day Avg (1

- in

- 10 yr) 5.83

365

- day Avg (1

- in

- 10 yr) 1.02

Entire Simulation Mean 0.540

Table 4 . Summary of Model Inputs for Profenofos.

Scenario MScottonSTD
Cropped Area Fraction 1.0
Koc (ml/g) 3890

Water Half

- Life (days) @ 25 °C 13.8

Benthic Half

- Life (days) @ 25 °C 3.8
Photolysis Half

- Life (days) @ 40 °Lat 266
Hydrolysis Half

- Life (days) 69.9

Soil Half

- Life (days) @ 25 °C 6.9

Foliar Half

- Life (days) 35

Molecular Wt 373.63
Vapor Pressure (torr) 9.3E

- 7
Solubility (mg/l) 20

Figure 2 . Yearly Peak Concentrations1 2 T able 5 . Estimated Environmental Concentrations (ppb) for Profenofos for NC cotton scenario

.

Peak (1

- in

- 10 yr) 21.1

4

- day Avg (1

- in

- 10 yr) 18.7

21

- day Avg (1

- in

- 10 yr) 10.3

60

- day Avg (1

- in

- 10 yr) 5.87

365

- day Avg (1

- in

- 10 yr) 0.981

Entire Simulation Mean 0.450

Table 6 . Summary of Model Inputs for Profenofos.

Scenario NCcottonSTD
Cropped Area Fraction 1.0
Koc (ml/g) 3890

Water Half

- Life (days) @ 25 °C 13.8

Benthic Half

- Life (days) @ 25 °C 3.8
Photolysis Half

- Life (days) @ 40 °Lat 266
Hydrolysis Half

- Life (days) 69.9

Soil Half

- Life (days) @ 25 °C 6.9

Foliar Half

- Life (days) 35

Molecular Wt 373.63
Vapor Pressure (torr) 9.3E

- 7
Solubility (mg/l) 20

Figure 3 . Yearly Peak Concentrations13 

### Appendix 2

– PRZM

- GW Modeling Results

Table 1. Groundwater Results for profenofos and the DELMARVA sweet corn

- Evesboro loamy sand , 30 year Scenario.

Peak Concentration (ppb) 0.00106

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 7.71E

- 05
Average Breakthrough Time (days) Incomplete
Throughputs 0.2339317

Table 2. Chemical Properties for Groundwater Modeling of profenofos for the DELMARVA sweet

corn - Evesboro loamy sand , 30 year Scenario.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.1

Table 3. Groundwater Results for Profenofos and the DELMARVA sweet corn

- Evesboro loamy sand , 100 year Scenario.

Peak Concentration (ppb) 6.38

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 1.33
Average Breakthrough Time (days) Incomplete
Throughputs 0.7563034

Table 4. Chemical Properties for Groundwater Modeling of Profenofos for the DELMARVA sweet

corn - Evesboro loamy sand, 10 0 year Scenario.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.114 Table 5 . Groundwater Results for Profenofos and the Florida Citrus

- FL Central Ridge, Polk County

- (Tampa) Met File (12842.dvf)

- Astatula sand, hrgb A , 30 year Scenario.



### Peak Concentration (ppb) 2.51

Post

- Breakthrough Mean Concentration (ppb) Incomplete

Entire Simulation Mean Concentration (ppb) 0.482
Average Breakthrough Time (days) Incomplete
Throughputs 0.2748974

Table 6 . Chemical Properties for Groundwater Modeling of Profenofos for the Florida Citrus

- FL Central Ridge, Polk County

- (Tampa) Met File (12842.dvf)

- Astatula sand, hrgb A , 30 year scenario

.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.1

Table 7 . Groundwater Results for Profenofos and the Florida Citrus

- FL Central Ridge, Polk County

- (Tampa) Met File (12842.dvf)

- Astatula sand, hrgb A , 100 year Scenario.

Peak Concentration (ppb) 16

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (p pb) 7.46
Average Breakthrough Time (days) Incomplete
Throughputs 0.9104421



### Table 8 . Chemical Properties for Groundwater Modeling of Profenofos for the Florida Citrus

- FL Central Ridge, Polk County

- (Tampa) Met File (12842.dvf)

- Astatula sand, hrgb A 

### , 100 year scenario

.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.115 Table 9 . Groundwater Results for Profenofos and the FLORIDA

- potato

- Met File (13889.dvf) Jacksonville , 30 year Scenario.

Peak Concentration (ppb) 8.79E

- 05

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 8.8E

- 06
Average Breakthrough Time (days) Incomplete
Throughputs 0.1274318

Table 10 . Chemical Properties for Groundwater Modeling of Profenofos for the FLORIDA

- potato

- Met File (13889.dvf) Jacksonville , 30 year Scenario.

.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.1

Table 1 1. Groundwater Results for Profenofos and the FLORIDA

- potato

- Met File (13889.dvf) Jacksonville , 100 year Scenario.

Peak Concentration (ppb) 1.96

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 0.292
Average Breakthrough Time (days) Incomplete
Throughputs 0.4219591

Table 1 2. Chemical Properties for Groundwater Modeling of Profenofos for the FLORIDA

- potato

- Met File (13889.dvf) Jacksonville , 100 year Scenario

.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.116 Table 13 . Groundwater Results for Profenofos and the GA

- Southern Coastal Plain, Tifton loamy sand

– PEANUTS , 30 year Scenario.

Peak Concentration (ppb) 3.03E

- 09

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 2.27E

- 10
Average Breakthrough Time (days) Incomplete
Throughputs 0.1667907

Table 14 . Chemical Properties for Groundwater Modeling of Profenofos for the GA

- Southern Coastal Plain, Tifton loamy sand

– PEANUTS , 30 year Scenario

.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.1

Table 1 5 . Groundwater Results for Profenofos and the GA

- Southern Coastal Plain, Tifton loamy sand

– PEANUTS , 100 year Scenario.

Peak Concentration (ppb) 0.0266

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 0.00295
Average Breakthrough Time (days) Incomplete
Throughputs 0.5518569

Table 16. Chemical Properties for Groundwater Modeling of Profenofos for the GA

- Southern Coastal Plain, Tifton loamy sand

– PEANUTS , 100 year Scenario

.

Koc (ml/g) 3890

Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.117 Table 17 . Groundwater Results for Profenofos and the NC Eastern Coastal Plain

- Norfolk loamy sand

– Cotton , 30 years Scenario.

Peak Concentration (ppb) 0.0193

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 0.00197
Average Breakthrough Time (days) Incomplete
Throughputs 0.288822

Table 1 8 . Chemical Properties for Groundwater Modeling of Profenofos for the NC Eastern Coastal Plain

- Norfolk loamy sand

– Cotton , 30 years Scenario

.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.1

Table 19. Groundwater Results for Profenofos and the NC Eastern Coastal Plain

- Norfolk loamy sand

– Cotton , 100 year Scenario.

Peak Concentration (ppb) 0.478

Post

- Breakthrough Mean Concentration (ppb) Incomplete
Entire Simulation Mean Concentration (ppb) 0.19
Average Breakthrough Time (days) Incomplete
Throughputs 0.9383513

Table 2 0 . Chemical Properties for Groundwater Modeling of Profenofos for the NC Eastern Coastal Plain

- Norfolk loamy sand

– Cotton , 100 year Scenario

.

Koc (ml/g) 3890
Surface Soil Half Life (days) 0
Hydrolysis Half Life (days) 69.9

Diffusion Coefficient Air (cm2/day) 0.032980
Henry's Constant 2.38E

- 7
Enthalpy (kcal/mol) 8.1