Page 2 of 27

The maximum EDWCs calculated in this assessment are shown in Table 1. In surface water, the 

highest estimated 1-in-10 year peak (acute) concentration of isofetamid is 96 μg/L, the highest 

estimated 1-in-10 year annual average concentration is 28 μg/L, and the highest estimated 30-

year annual average concentration is 16 μg/L. In groundwater, the highest estimated peak 

concentration is 49 μg/L, and the highest estimated post-breakthrough average concentration is 

43 μg/L. EFED recommends using the 1-in-10 year peak surface water EDWC value (96 

μg/L) for assessing human health dietary risk from acute exposures and the maximum 

post-breakthrough average groundwater EDWC value (43 μg/L) for assessing human 

health dietary risk from chronic and life-time/cancer exposures. 

Table 1. Maximum estimated drinking water concentrations (EDWCs) in parts per billion (μg/L) 

resulting from applications of Isofetamid on the Proposed Low-Growing Berries Subgroup 13-07G 

and Turf Uses. 

Drinking 

Water Source 

(model) 

Model Scenario, Use 

Modeled, & Application 

Method 

Acute Chronic Cancer 

μg/L 

Surface Water 

(SWCC) 

California Strawberry RedLegged Frog (RLF) 

Scenario 

Low-Growing Berries 

Subgroup 13-07G 

5 Aerial Applications of 

0.442 lb a.i./acre 

Peak 

1-in-10 Year 

Chronic 

1-in-10 Year 

30-year Annual 

Average 

96 28 16 

Groundwater 

(PRZM-GW 

30-year 

simulation) 

Wisconsin Corn Scenario 

Turf 

7 Ground Applications 

Total: six of 0.567 lb 

a.i./acre and one of 0.248 

lb a.i./acre 

Peak Post-Breakthrough Average 

49 43 

Data Uncertainties 

There are only anaerobic soil metabolism data from one soil for isofetamid. However, given the 

compound’s persistence in the single anaerobic soil, as well as its persistence in anaerobic 

aquatic test systems, additional anaerobic soil metabolism data are not expected to alter the 

EDWCs modeled and recommended for use in the human health dietary assessment. 

Parent isofetamid is only considered in this DWA based on ROCKS recommendations 

(D411110). Because of this, any uncertainties concerning degradate data do not impact the 

EDWCs recommended for use in the human health dietary assessment. 
Page 3 of 27

Uses Proposed and Assessed

Isofetamid is being proposed for use on almond, lettuce, grapes (Subgroup 13-07F), low growing 

berries (Subgroup 13-07G), rapeseed (Subgroup 20A), and turf (commercial and residential). 

Isofetamid is applied as a foliar spray via ground or aerial equipment or via chemigation. There 

are two isofetamid end-use products being proposed for registration in the United States: 

Isofetamid 400SC Agricultural Fungicide (flowable suspension concentrate; 36.0% isofetamid; 

the product does not contain any other active ingredients); and Isofetamid Turf Fungicide 

(flowable suspension concentrate; 36.0% isofetamid; the product does not contain any other 

active ingredients). According to the proposed labels, isofetamid can be applied at a single 

maximum application rate of 0.572 lb a.i./acre (grapes) and a yearly maximum application rate 

of 3.65 lb a.i./acre (turf) (see Table 2). At most, it can be applied eight times per year (turf). The 

minimum application interval is 7 or 14 days, depending on the proposed use. For all of the 

proposed uses, except turf, isofetamid can be applied via chemigation and ground or aerial spray. 

Isofetamid can only be applied to turf via ground spray. For resistance management, both 

proposed labels stipulate that no more than two sequential applications of isofetamid can be 

made to use sites. 

Based on the proposed single and annual application rates, application methods, and exposure 

estimates from the recently conducted isofetamid Ecological Risk Assessment2

, it is expected 

that low-growing berry uses will result in the highest surface water EDWCs and turf uses will 

result in the highest groundwater EDWCs. Note that 

Table 2. Application Information from the Proposed Isofetamid Labels1. 

Crop 

Maximum 

Individual 

Application 

Rate 

lbs a.i./A 

Number of 

Applications/ year

Minimum 

Application 

Interval 

(days) 

Max 

Annual 

Application 

Rate in lbs 

a.i./A/year 

Application 

Method Comments 

Almond 0.442 42 7 1.77 

Ground 

Aerial 

Chemigation3

- Do not apply 

after first 

cover. 

- Do not make 

more than two 

sequential 

applications of 

isofetamid. 

Lettuce 

(head and 

leaf) 

0.320 2 14 0.64 

Ground 

Aerial 

Chemigation3

- on direct 

seeded lettuce 

make first 

application 

after 

emergence, 

thinning or 

prior to onset 

of disease 

 

2

 By default, the Surface Water Concentration Calculator (SWCC) calculates exposure estimates for both the EPA 

farm pond and the EPA reservoir. EPA reservoir EDWCs calculated during the development of the isofetamid 

Ecological Risk Assessment were used to triage SWCC scenarios resulting in higher concentrations for 

consideration in this DWA. 
Page 4 of 27

Crop 

Maximum 

Individual 

Application 

Rate 

lbs a.i./A 

Number of 

Applications/ year

Minimum 

Application 

Interval 

(days) 

Max 

Annual 

Application 

Rate in lbs 

a.i./A/year 

Application 

Method Comments 

development; 

on transplanted 

lettuce make 

application 

immediately 

after 

transplanting 

or prior to 

disease 

development; 

make a second 

application iof 

conditions 

continue to 

favor disease 

development. 

- Do not make 

more than two 

sequential 

applications of 

isofetamid. 

Grapes 

(Crop 

Subgroup 

13-07F)4

0.572 32

 7 1.72 

Ground 

Aerial 

Chemigation3

- Do not make 

more than two 

sequential 

applications of 

isofetamid. 

Low 

growing 

berries 

(Crop 

Subgroup 

13-07G)5

0.442 52

 7 2.28 

Ground 

Aerial 

Chemigation3

- Do not make 

more than two 

sequential 

applications of 

isofetamid. 

Rapeseed 

(Canola) 

(Crop 

Subgroup 

20A)6

0.312 2 14 0.63 

Ground 

Aerial 

Chemigation3

- Initiate 

applications at 

20 -40% 

flowering or 

prior to disease 

development. 

A second 

application 

may be made 

near the end of 

flowering. 

- Do not make 

more than two 

sequential 

applications of 

isofetamid. 
Page 5 of 27

Crop 

Maximum 

Individual 

Application 

Rate 

lbs a.i./A 

Number of 

Applications/ year

Minimum 

Application 

Interval 

(days) 

Max 

Annual 

Application 

Rate in lbs 

a.i./A/year 

Application 

Method Comments 

Turf7 0.567 

8 applications are 

allowed at 0.452 lb 

a.i./acre/application 

6 applications are 

allowed at 0.567 lb 

a.i./acre/application 

in addition to 1 

application of 0.248 

lb 

a.i./acre/application8

14 3.65 Ground 

- Do not apply 

by air or 

through any 

type of 

irrigation 

system 

- Do not make 

more than two 

sequential 

applications of 

isofetamid. 

1 There is 3.33 lb a.i. (isofetamid) in one gallon of the isofetamid products. 

2 This is not specified on the label; it is assumed by dividing the maximum application rate allowed/year by the 

maximum single application rate. 

3 Only center pivot, motorized lateral move, traveling gun, solid set or portable (wheel move, side roll, end tow, or 

hand move) irrigation systems. 

4

 Includes amur river grape. Gooseberry, grape (wine, table, raisin, and juice), kiwifruit (hardy), maypop, schisandra 

berry, and cultivars, varieties, and/or hybrids of these. 

5

 Includes bearberry, bilberry, blueberry (low bush), cloudberry, cranberry, lingonberry, muntries, partrisgeberry, 

strawberry, and cultivars, varieties, and/or hybrids of these. 

6

 Includes borage, crambe, cuphea, echium, flax seed, gold of pleasure, hare’s ear mustard, lesquerella, lunaria, 

meadowfoam, milkweed, mustard seed, oil radish, poppy seed, rapeseed, sesame, sweet rocket, and cultivars, 

varieties, and/or hybrids of these. 

7

 Turf areas associated with golf courses (greens, tees and fairways), sod farms, seed farms, college and professional 

sports fields, residential and commercial lawns. Application by homeowners to residential turf is prohibited. 

8

 Eight applications of 0.452 lb a.i./acre would result in the maximum annual rate of 3.65 lb a.i./acre. However, the 

maximum single application rate specified on the label is 0.567 lb a.i./acre. To fully account for uses at this higher 

single application rate, the number of applications per year is also reported in this table as six applications at the 

maximum single application rate in addition to a seventh application at a lower single application rate of 0.227 lb 

a.i./acre. 

Environmental Fate and Transport Characterization

Degradation 

Isofetamid rapidly degrades as a result of aqueous photolysis, and degradation is also expected to 

occur as a result of aerobic metabolism in soil and water. In the aqueous photolysis study, 

isofetamid degraded to half its initial concentration within two days (1.4 - 1.8 days at pH 7). 

Half-lives calculated for isofetamid in the aerobic soil metabolism studies ranged from 25 to 66 

days, with comparable DT50s. Half-lives calculated for isofetamid in the aerobic aqueous 

metabolism study ranged from 108 to 173 days. 
Page 6 of 27

Laboratory studies indicate that isofetamid is stable to hydrolysis and soil photolysis, and very 

persistent in anaerobic environments. No degradation of isofetamid occurred in the hydrolysis 

study. The half-lives for soil photolysis ranged from 294 days for dry soil to 354 days for moist 

soil. The half-life calculated for the anaerobic soil metabolism study was 572 days, while the 

half-lives calculated for anaerobic aquatic metabolism exceeded 1,000 days. Based on these 

half-life estimates, the modeling conducted in this assessment assumes that isofetamid residues 

do not degrade in anaerobic environments. 

Figure 1 in the Degradates section illustrates the proposed degradation pathways for isofetamid. 

Mobility and Transport 

Isofetamid is expected to be moderately mobile and may enter surface water through runoff and 

groundwater via leaching. Isofetamid’s vapor pressure (4.4 ×10-11 Torr) and Henry’s Law 

Constant (1.2×10-5 Pa-m3

/mol) indicate that volatilization is not a likely dissipation pathway. 

Adsorption/desorption testing for isofetamid was conducted on two US soils, two UK soils, and 

one Japanese soil (volcanic ash). For these five soils, the Kd values range from 6.59 to 19.43 

mL/g, while KF values range from 6.64 to 20.79 with 1/n values ranging from 0.873 to 0.991. Koc 

values range from 281 to 615 mL/g-organic carbon and KFoc values range from 274 to 603 mL/gorganic carbon. Results from this study are also summarized in Appendix A, Table A2. 

The adsorption/desorption study results indicate that soil sorption of isofetamid is influenced by 

soil organic carbon content. The coefficient of variance is lower for the Koc’s and KFoc’s than for 

the Kd’s and KF’s indicating a correlation between isofetamid soil sorption and soil organic 

carbon content; however, a regression analysis of percent organic carbon versus KF for the five 

soils did not find this relationship to be statistically significant. Adsorption and desorption both 

decreased slightly with increasing concentration in the study. Based on its KFoc values, 

isofetamid would be classified as moderately mobile (FAO, 2000). 

Field Studies 

Several terrestrial field dissipation studies have been completed for isofetamid (MRIDs 

49011993, 49018438, 49018441, 49011992, 49018442). Results from these studies are 

summarized in Appendix A, Table A4. Three studies were conducted on bare ground sites in 

both the US (North Dakota, California) and Canada (Saskatchewan), and two studies were 

conducted on turf in the US (North Carolina, Arkansas). Several applications of isofetamid were 

made at each site. The single application rates in each study ranged between 500 and 800 g 

a.i./ha, which are comparable to the proposed application rate for isofetamid. 

Isofetamid dissipation half-lives calculated for the whole soil profile ranged from 7 to 47 days 

for four of the five studies. The half-life for the Aberdeen, Saskatchewan study was 217 days, 

and this longer half-life was attributed to a prolonged winter. With the exception of the 

Saskatchewan study, DT50s in the terrestrial field dissipation studies were generally consistent 

with the half-lives calculated for the aerobic soil metabolism studies. However, the carryover 
Page 7 of 27

percentages in some of the terrestrial field dissipation studies are indicative of higher persistence 

in surface soils. 

At all sites, isofetamid residues were observed in the top 15 cm; however, isofetamid was 

observed up to a depth of 30 cm in the California and North Carolina studies. 

Degradates 

Identification information and structures for isofetamid degradates are summarized in Appendix 

A, Table A1. A summary of maximum amount of transformation products observed in the 

laboratory fate studies is in Appendix A, Table A5. 

4HP and PPA are the environmental degradates that have structural similarity to isofetamid and 

are therefore assumed to be as toxic as isofetamid. However, these two degradates were 

observed at levels <11.8% of the applied radioactivity. Based on the low levels expected relative 

to parent isofetamid, these degradates are not considered residues of concern for this DWA 

(ROCKS Memo, D411110). 

Another structurally similar transformation product, GPTC, is a plant metabolite. GPTC was 

observed in turf thatch collected in the terrestrial field dissipation studies; however, because it 

was not observed in any laboratory fate studies or in soil samples collected in the terrestrial field 

dissipation studies, it is not expected to be present in drinking water resources and is not 

included in this DWA (ROCKS Memo, D411110). 

Figure 1 shows the applicant’s depiction of the potential degradation pathways of isofetamid in 

soil, water, and air based on chemical structures and observed transformation products in the fate 

studies. This figure does not take into consideration the potential for numerous degradation 

products that may form from isofetamid degradates prior to mineralization. 
Page 8 of 27

Figure 1. Potential Degradation Pathway of Isofetamid 

Drinking Water Modeling 

Models and Scenarios Used 

Detailed descriptions, documentation, and links for running the models discussed in the 

paragraphs below may found at http://www.epa.gov/oppefed1/models/water/index.htm. 

Surface Water Modeling 

The Surface Water Concentration Calculator (SWCC version 1.101) model was used to generate 

Estimated Drinking Water Concentrations (EDWCs). The SWCC generates daily, 1-in-10-year, 

and 30-year average EDWCs of isofetamid that may occur in surface water bodies adjacent to 

application sites receiving isofetamid through runoff and spray drift. SWCC simulates pesticide 

application, movement and transformation in a watershed and the resultant pesticide loadings to 

a receiving water body via runoff, erosion, and spray drift, and then simulates the fate of the 

pesticide and resulting concentrations in the water body. The standard watershed geometry used 

for drinking water assessments assumes application to a 427-acre watershed that drains into an 

adjacent 13-acre reservoir that is an average of 2.7 meters deep (4,665,600 m3

 volume). 

In this assessment, EFED’s standard scenarios as well Red-Legged Frog (RLF) and 

Organophosphate (OP) assessment scenarios were used within the SWCC and are listed in Table 

3. The metadata for each scenario identifies the growing season for the crop of concern in that 

scenario. EDWCs were calculated based on the crop emergence date identified in the scenario 

metadata and listed in Table 3. The national agricultural PCA of 0.91 was applied to the model 

outputs. Guidance for using PCAs and a thorough discussion of this method and comparisons of 

monitoring and modeling results for selected pesticide/crop/site combinations is located at 

http://www.epa.gov/oppefed1/models/water/pca_adjustment_dwa.html. 

Ground Water Modeling

Groundwater EDWCs for isofetamid resulting from the use with the highest annual application 

rate, turf, were derived using the Pesticide Root Zone Model for Groundwater (PRZM-GW v. 

1.07). PRZM-GW is a one-dimensional, finite-difference model that estimates the 

concentrations of pesticides in groundwater. It 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 multiple 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 contaminations, are available for use 

with PRZM-GW for risk assessment purposes. In the PRZM-GW simulations, each of these 

standard scenarios was used (scenario versions installed 4/28/14). PRZM-GW output values 

represent pesticide concentrations in a vulnerable groundwater supply that is located directly 

beneath a rural agricultural field. Note that, unlike in surface water modeling, PCAs are not used 
Page 9 of 27

with PRZM-GW per EFED guidance. In this assessment, PRZM-GW is used as a Tier-1 screen. 

For more information on potential Tier II refinements in PRZM-GW modeling, see 

http://www.epa.gov/oppefed1/models/water/przm_gw/wqtt_przm_gw_guidance.htm). 

The default PRZM-GW assumptions used in calculating Tier I groundwater EDWCs for 

isofetamid include the following: 

 Isofetamid is used at the maximum labeled rate for 30 consecutive years. 

 There are no well setbacks. 

 Removal of the pesticide via runoff or erosion is negligible. 

 The saturated zone is a shallow (<100 feet), unconfined aquifer with a water table depth 

that corresponds to its respective scenario location. 

 The well screen extends from the aquifer surface to 1 meter below the aquifer surface. 

 The pesticide undergoes aerobic soil metabolism in the top 10 cm of soil; the aerobic soil 

metabolism rate declines linearly to 1 meter below the soil surface, below which only 

abiotic degradation processes (i.e., hydrolysis) occur. 

Modeling Input Parameters 

Input parameters used in the SWCC are found in Table 3 and 

Table 4. The pesticide application assumptions used in the SWCC are summarized in Table 3, 

while the environmental fate properties used in the SWCC summarized in 

Table 4. Model input parameters for PRZM-GW are summarized in 

Table 5. Model input values were prepared following EFED input parameter guidance. 

Although proposed label language prohibits more than two sequential isofetamid applications, 

surface water and groundwater modeling assumes that all isofetamid applications allowed within 

the year are separated by the minimum re-application interval. This is a conservative 

assumption, and may result in higher EDWCs. With regard to surface water modeling for lowgrowing berries, ground and chemigation applications are also proposed as application methods 

for low-growing berries subgroup 13-07G; however, only the aerial application was assessed 

because it is expected to be protective of exposures resulting from ground and chemigation 

application methods (i.e., modeling for aerial applications is protective of ground and 

chemigation applications). 

Table 3. Summary of Isofetamid Low-Growing Berries Subgroup 13-07G Application 

Input Parameters Used in the SWCC. 
Page 10 of 27

Model Input 

Parameter Input Value and Unit Source/ Comment 

SWCC Scenarios 

CA Strawberry (RLF) 

FL Strawberry 

OR Berries (OP) 

Proposed End-Use Labels (EPA File Symbols 71512-EE 

and 71512-EG). FL Strawberry scenario includes 

irrigation. RLF is the acronym for Red-Legged Frog 

and OP is the acronym for Organophosphate. 

Maximum Single 

Application Rate 0.495 kg ai/ha Proposed End-Use Labels (EPA File Symbols 71512-EE 

and 71512-EG) 

Maximum 

Number of 

Applications 

5 Proposed End-Use Labels (EPA File Symbols 71512-EE 

and 71512-EG) 

Method of 

Application Aerial 

The label allows aerial, ground, and chemigation 

applications of isofetamid on the low-growing berries 

subgroup. Only aerial was considered in the modeling 

for the low-growing berries subgroup, as model results 

for the aerial applications are expected to be protective 

of ground and chemigation applications. 

Application 

Efficiency 0.95 December 2013 EFED Spray Drift Guidance 

Spray Drift 

Fraction 0.135 December 2013 EFED Spray Drift Guidance 

Type of 

Application Foliar Proposed End-Use Labels (EPA File Symbols 71512-EE and 71512-EG) 

Initial Date of 

Application5 

(month/day) 

CA Strawberry (RLF): 1/1 

FL Strawerry: 10/1 

OR Berries (OP): 4/1 

Initial application dates were assumed to occur on the 

crop emergence dates listed in scenario metadata. 

Minimum 

Interval between 

Applications 

7 days 

Proposed End-Use Labels (EPA File Symbols 71512-EE 

and 71512-EG). Note that proposed label language 

prohibiting more than two sequential isofetamid 

applications is not considered in the modeling. 

Table 4. Summary of Isofetamid Environmental Fate Input Parameters Used in the SWCC. 

Model Input Parameter Input Value and Unit Source/Comments 

Foliar Half-life Stable Assumption based on Input Parameter 

Guidance 

Soil Partition Coefficient KFoc

491 mL/goc

MRID 49011979 

Mean of isofetamid KFoc's calculated for five 

soils. 

Hydrolysis Stable MRID 49011976 
Page 11 of 27

Model Input Parameter Input Value and Unit Source/Comments 

Aerobic Soil Metabolism Halflife (20°C) 61.52 days MRIDs 49011981 and 49011982 

The 90th percentile of four soil half-lives. 

Anaerobic Soil Metabolism 

Half-life (20°C) Stable MRID 49011985 

Aerobic Aquatic Metabolism 

Half-life (20°C) 166.5 days 

MRID 49011986 

The 90th percentile of two test system halflives. 

Anaerobic Aquatic Metabolism 

Half-life (20°C) Stable MRID 49011987 

Aqueous Photolysis 

Half-life 

1.8 days 

MRID 49011977 

The longer half-life of the two half-lives 

calculated in the study. 

Vapor pressure (25°C) 4.4 ×10-11 Torr MRID 49011905 

Solubility in water (20oC) 5.33 mg/L MRID 49011905 

Molecular Weight 359.48 g/mole --- 

Table 5. Inputs Used to Model Groundwater EDWCs for the Proposed Isofetamid Turf Use using 

PRZM-GW. 

Model Input Parameter PRZM-GW Input Value and 

Unit Source/Comments 

Maximum Application 

Rate and Number of 

Applications 

6 applications of 0.635 kg ai/ha 

1 application of 0.278 kg ai/ha 

EPA File Symbols 

71512-EE and 

71512-EG 

Method of Application CAM 2, Above Canopy 

EPA File Symbols 

71512-EE and 

71512-EG 

Date of Initial Application 0 days post-emergence 

Emergence dates are 

specified in each 

PRZM-GW 

scenario. 

Minimum Interval 

between Applications 14 days 

EPA File Symbols 

71512-EE and 

71512-EG 

Soil Partition Coefficient 

KFoc

491 mL/goc 

MRID 49011979 

Mean of isofetamid 

KFoc's calculated for 

five soils. 

Hydrolysis Half-Life Stable MRID 49011976 
Page 12 of 27

Model Input Parameter PRZM-GW Input Value and 

Unit Source/Comments 

Aerobic Soil Metabolism 

Half-Life 61.52 days 

MRIDs 49011981 

and 49011982 

The 90th percentile 

of four soil halflives. 

Modeling Results 

Surface Water 

Table 6 reports the EDWCs calculated for each low-growing berry SWCC (i.e., surface water) 

scenario. The maximum 1-in-10 year peak EDWCs in surface water range from 15 to 96 μg/L, 

the 1-in-10 year annual average EDWCs in surface water range from 6 to 28 μg/L, and the 30-

year average EDWCs range from 5 to 16 μg/L. The California Strawberry (RLF) scenario 

results in the maximum EDWCs, as well as the maximum peak EDWC of the uses evaluated in 

this assessment. The SWCC output data for the surface water EDWCs for the California 

Strawberry (RLF) scenario are attached in Appendix B. 

Table 6. Isofetamid Surface Water EDWCs for the Proposed Low-growing Berries (Crop 

Subgroup 13-07G) Use.

SWCC Crop 

Scenario 

App. 

method 

Percent 

Cropped 

Area 

App. 

Date 

1-in-10 year 

Peak EDWC 

μg/L 

1-in-10 year 

Annual EDWC 

μg/L 

30-year 

Average 

EDWC 

μg/L 

CA 

Strawberry 

(RLF) 

Aerial 0.91 

1-Jan 96 28 16 

FL Strawberry 1-Oct 50 8 5 

OR Berries 

(OP) 1-Apr 15 6 5 

Ground Water 

Table 7 reports the Tier I groundwater EDWCs calculated using PRZM-GW; the peak EDWCs 

in this 30-year simulation range from 0.0023 to 49.2 μg/L, while the post-breakthrough average 

EDWCs reached a maximum of 42.5 μg/L. The Wisconsin Corn scenario results in the 

maximum EDWCs for the turf use. 

Figure 2 illustrates the EDWCs modeled over the 30-year simulation period in the Wisconsin 

Corn scenario. 

Table 7. Isofetamid Groundwater EDWCs for the Proposed Turf Use - 30-Year Simulation. 
Page 13 of 27

Peak

Post‐

Breakthrough

Average

μg/L

DMV Corn       10.1      7.63

FL Citrus      40.4 38.9

FL Potato    0.0023 Incomplete

GA Peanuts      3.43      3.24

NC Cotton      5.43      4.84

WI Corn      49.2      42.5
Page 14 of 27

Figure 2. Estimated Groundwater Concentrations of Isofetamid from Use on Turf for a 30-

Year Simulation using PRZM-GW Wisconsin Corn Scenario (ppb = μg/L)*

*Maximum Single Application rate 0.567 lb a.i./acre for 6 sequential

applications and 0.248 lb a.i./acre for the 7th application;  Maximum

Annual Application rate 3.65 lb a.i./acre; Minimum Re‐Application

Interval 14 days; 7 Applications; Initial application modeled is 0 days

post‐emergence, based on emergence date in the scenario

 
Page 15 of 27

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Arlington, VA. 

USEPA 2014a. D409629. Ecological Risk Assessment for the Section 3 Registration of the 

New Chemical Isofetamid (draft). U.S. Environmental Protection Agency, Office of Pesticide 

Programs, Environmental Fate and Effects Division. Arlington, VA. 

USEPA 2014b. D411110. Isofetamid: Report of the Residues of Concern Knowledgebase 

Subcommittee (draft). U.S. Environmental Protection Agency, Office of Pesticide Programs, 

Health Effects Division. Arlington, VA. 

USEPA 2014c. PRZM5 A Model for Predicting Pesticide in Runoff, Erosion, and Leachate: 

User Manual. Undated, issued 2014. U.S. Environmental Protection Agency, Office of 

Pesticide Programs, Environmental Fate and Effects Division. Arlington, VA. 

USEPA 2014d. Surface Water Concentration Calculator User Manual. May 1, 2014. U.S. 

Environmental Protection Agency, Office of Pesticide Programs, Environmental Fate and Effects 

Division. Arlington, VA. 

USEPA 2014e. The Variable Volume Water Model and the USEPA Standard Water Bodies for 

Pesticide Risk Assessments. March 12, 2014. U.S. Environmental Protection Agency, Office of 

Pesticide Programs, Environmental Fate and Effects Division. Arlington, VA. 

 

Submitted Fate and Transport Studies 

49018438 McDonald, J.; Wiedmann, J. (2013) Terrestrial Field Dissipation of IKF-5411 

Applied to Bareground in Aberdeen, SK, Canada - 2010. Project Number: 

IB/2010/JLW/005/OCR, 100349. Unpublished study prepared by ISK BioSciences 

Corporation and Golden Pacific Laboratories, LLC (GPL). 406p. 

49018441 McDonald, J.; Wiedmann, J. (2013) Field Soil Dissipation for IKF-5411 400SC 

Applied to Turf in Proctor, AR - USA 2011. Project Number: 

IB/2011/JLW/010/01/01/OCR, RICERCA/027501. Unpublished study prepared by 

ISK BioSciences Corporation and Ricerca Biosciences, LLC. 342p. 

49018442 McDonald, J. ; Wiedmann, J. (2013) Field Soil Dissipation for IKF-5411 400SC 

Applied to Turf in Goldsboro, NC - USA 2011. Project Number: 

IB/2011/JLW/008/01/01/OCR, RICERCA/027502. Unpublished study prepared by 

ISK BioSciences Corporation and Ricerca Biosciences, LLC. 362p. 
Page 17 of 27

49018445 Wiedmann, J. (2013) Summary of the Environmental Fate of IKF-5411 

(Isofetamid). Project Number: IB/2013/MG/005/01/OCR. Unpublished study 

prepared by ISK BioSciences Corporation. 16p. 

49011976 Fletcher, T. (2010) [Carbon 14]IKF-5411: Hydrolytic Stability. Project Number: 

2244/073/OCR. Unpublished study prepared by Covance Laboratories, Ltd. 43p. 

49011977 Graham, R. (2012) [Carbon 14]IKF-5411: Photodegradation and Quantum Yield in 

Sterile, Aqueous Solution. Project Number: 2244/074/OCR. Unpublished study 

prepared by Covance Laboratories, Ltd. 182p. 

49011978 Lewis, C. (2010) [Carbon 14]IKF-5411: Photodegradation on Soil Surface. Project 

Number: 2244/075/OCR. Unpublished study prepared by Covance Laboratories, 

Ltd. 113p. 

49011979 Fletcher, T. (2010) [Carbon 14]IKF-5411: Adsorption/Desorption in Five Soils. 

Project Number: 2244/078/OCR. Unpublished study prepared by Covance 

Laboratories, Ltd. 87p. 

49011980 Lewis, C. (2012) 4HP (Metabolite of IKF-5411): Adsorption/Desorption in Five 

Soils. Project Number: 8204073/OCR. Unpublished study prepared by Covance 

Laboratories, Ltd. 136p. 

49011981 Lewis, C. (2010) [Carbon 14]IKF-5411: Aerobic Soil Metabolism and Degradation: 

Final Report. Project Number: 2244/068/OCR. Unpublished study prepared by 

Covance Laboratories, Ltd. 85p. 

49011982 Lewis, C. (2010) [Carbon 14]IKF-5411: The Rate of Degradation in Three Soils 

Under Aerobic Conditions. Project Number: 2244/084/OCR. Unpublished study 

prepared by Covance Laboratories, Ltd. 78p. 

49011983 Lewis, C. (2010) [Carbon 14]IKF-5411: The Rate of Degradation in One Soil at 10 

(Degrees Celsius) Under Aerobic Conditions. Project Number: 8204074/OCR. 

Unpublished study prepared by Covance Laboratories, Ltd. 59p. 

49011985 Fletcher, T. (2010) [Carbon 14]IKF-5411: Anaerobic Soil Metabolism and 

Degradation. Project Number: 2244/076/OCR. Unpublished study prepared by 

Covance Laboratories, Ltd. 77p. 

49011986 Hurst, I. (2012) [Carbon 14]IKF-5411: Degradation in Water-sediment Systems 

Under Aerobic Conditions. Project Number: 2244/072/OCR. Unpublished study 

prepared by Covance Laboratories, Ltd. 99p. 

49011987 Hurst, L. (2011) [Carbon 14]IKF-5411: Degradation in Water-Sediment Systems 

Under Anaerobic Conditions. Project Number: 2244/079/OCR. Unpublished study 

prepared by Covance Laboratories, Ltd. 116p. 

49011988 Schoenan, E. (2010) Independent Laboratory Validation of Ishihara Sangyo Kaisha 

(ISK) Residue Analytical Method for the Determination of IKF-5411 and its 

Metabolites 4HP in Soil: (Document Number: F-559). Project Number: 

IB/2010/JLW/008/01/00/OCR, 100341. Unpublished study prepared by Golden 

Pacific Laboratories, LLC (GPL). 117p. 
Page 18 of 27

49011989 Furuo, R. (2010) Validation of the Residue Analytical Method for the Determination 

of IKF-5411 and its Metabolite 4HP in Soil. Project Number: F/559/OCR. 

Unpublished study prepared by Ishihara Sangyo Kaisha, Ltd. 58p. 

49011990 Furuo, R. (2012) Validation of an Analytical Method for the Determination of IKF5411 and 4HP in Sediment. Project Number: F/561/OCR. Unpublished study 

prepared by Ishihara Sangyo Kaisha, Ltd. 39p. 

49011991 Boatwright, M. (2012) Freezer Storage Stability of IKF-5411 in Soil. Project 

Number: IB/2010/JLW/011/01/00/OCR, 100354. Unpublished study prepared by 

Golden Pacific Laboratories, LLC (GPL). 126p. 

49011992 McDonald, J.; Wiedmann, J. (2012) Terrestrial Field Dissipation of IKF-5411 

Applied to Bareground in Kerman, CA - USA 2010. Project Number: 

IB/2010/JLW/003/01/01/OCR, 100347. Unpublished study prepared by ISK 

BioSciences Corp. and Golden Pacific Laboratories, LLC (GPL). 333p. 

49011993 McDonald, J.; Wiedmann, J. (2012) Terrestrial Field Dissipation of IKF-5411 

Applied to Bareground in Northwood, ND - USA 2010. Project Number: 

IB/2010/JLW/004/01/01, 100348/OCR. Unpublished study prepared by Golden 

Pacific Laboratories, LLC (GPL). 334p. 

49011994 Richardson, M. (2012) IKF-5411 and its Metabolites 3-MTCAM, IBA and PPA: 

Validation of an Analytical Method for the Determination of Residues in Surface 

and Drinking Water. Project Number: 8261479/OCR. Unpublished study prepared 

by Covance Laboratories, Ltd. 120p. 
Page 19 of 27

Appendix A. Fate Data for Isofetamid Parent and Degradates 

Table A1. Chemical Identification Information for Isofetamid and Isofetamid Degradates and 

Metabolites. 

Common 

Name and 

Registrant 

Code Name 

Chemical Name and Smiles Code Structure 

Isofetamid 

(IKF-5411)

N-[1,1-dimethyl-2-[2-methyl-4-(1-

methylethoxy)phenyl]-2-oxoethyl]-3-methyl-2-

thiophenecarboxamide 

C(C)(C)(C(=O)c1c(C)cc(OC(C)C)cc1)NC(=O)C

1=C(C)C=CS1 

Molecular Weight = 359.48 

4HP 

(YN-5394) 

N-[1,1-dimethyl-2-(4-hydroxy-2-methylphenyl)-

2-oxoethyl]-3-methyl-2-thiophenecarboxamide 

C(C)(C)(C(=O)c1c(C)cc(O)cc1)NC(=O)C1=C(C)

C=CS1 

Molecular Weight = 317.40 

PPA 

(YN-6187) 

2-[3-methyl-4-[2-methyl-2-(3-methylthiophene-2-

carboxamido)propanoyl]phenoxy]propanoic acid 

C(C)(C)(C(=O)c1c(C)cc(OC(=O)O)cc1)NC(=O)

C1=C(C)C=CS1 

Molecular Weight = 389.46 

 

IBA 

(HM-939) 

2-methyl-4-(2-propyloxy)benzoic acid 

C(=O)(O)c1c(C)cc(OC(=O)O)cc1 

3-MTCAM 

3-methyl-2-thiophenecarboxamide 

C(N)(=O)C1=C(C)C=CS1 
Page 20 of 27

Common 

Name and 

Registrant 

Code Name 

Chemical Name and Smiles Code Structure 

3-MTCA 

3-methyl-2-thiophenecarboxylic acid 

C(=O)(O)C1=C(C)C=CS1 

GPTC 

N-[l,1 –dimethyl-2-(4-β-D-glucopyranosyloxy-2-

methylphenyl)-2-oxoethyl] -3 -methyl-2-

thiophenecarboxamide 

C(C)(C)(C(=O)c1c(C)cc(OC2C(O)C(O)C(O)C(C

O)O2)cc1)NC(=O)C1=C(C)C=CS1 

Table A2. Isofetamid Parent: Select Physical-Chemical and Fate Properties. 

Parameter Value and Units1 Source and/or Comment 

Water Solubility at 20oC 5.33 mg/L MRID 49011905 

Vapor Pressure at 25oC 4.2×10-7 Pa 

4.4 ×10-11 Torr 

MRID 49011905 

Non-volatile under field conditions 

Henry’s Law constant 1.2×10-5 Pa-m3/mol MRID 49011905 

Log Dissociation Constant 

(pKa) 

The pure active ingredient did not 

dissociate in pH 4 to 10 solutions. MRID 49011905 

Octanol-water partition 

coefficient (Kow) log Kow = 2.5 MRID 49011905 

Not likely to bioconcentrate. 

Soil Partition Coefficient 

KF (25°C) 

US Loamy Sand: 6.64 mL/g 

(

1

/n = 0.873) 

US Loam: 17.17 mL/g 

(

1

/n = 0.921) 

UK Loam or Silt Loam: 20.79 mL/g 

(

1

/n = 0.991) 

UK Clay Loam: 13.68 mL/g 

(

1

/n = 0.924) 

Japanese Sandy Loam (Volcanic 

Ash): 14.86 mL/g 

(

1

/n = 0.933) 

Mean: 14.63 mL/g 

MRID 49011979 

Supplemental 
Page 21 of 27

Parameter Value and Units1 Source and/or Comment 

Soil Partition Coefficient 

KFoc (25°C) 

US Loamy Sand: 602.6 mL/goc 

US Loam: 591.9 mL/goc

UK Loam or Silt Loam: 534.9 

mL/goc

UK Clay Loam: 274.3 mL/goc

Japanese Sandy Loam (Volcanic 

Ash): 449.6 mL/goc

Mean: 491 mL/goc

MRID 49011979 

Supplemental 

Terrestrial Field 

Dissipation DT50's 

ND, USA: 6.98 days (IORE) 

SK, Canada: 217 days (SFO) 

AR, USA: 35 days (SFO) 

CA, USA: 46.5 days (SFO) 

NC, USA: 29 days (SFO) 

MRIDs 49011993, 49018438, 49018441, 

49011992, and 49018442 

Acceptable 

SFO=single first order; DFOP=double first order in parallel; IORE=indeterminate order (IORE) 

1 Representative half-lives are estimated SFO half-lives (for EFED modeling inputs) from a degradation curve 

that does not necessarily follow the SFO equation. Representative half-life values were calculated using 

nonlinear regression and SFO, DFOP, or IORE equations. The equations can be found in the document, 

Standard Operating Procedure for Using the NAFTA Guidance to Calculate Representative Half-life Values and 

Characterizing Pesticide Degradation (US EPA 2012). Representative half-life values calculated in this table do 

not include unextracted residues, as exhaustive extraction methods were used in the studies. 

2 Representative half-lives for moist soil photolysis were corrected for the moist dark control. 

 
Page 22 of 27

Table A3. Representative Half-Lives for Isofetamid. 

Study System Details Representative Half-Life* 

(Kinetic Equation) MRID 

Abiotic Hydrolysis pH 4, 7, 9 at 50oC stable 49011976 

Supplemental 

Aqueous Photolysis 

Sterile Buffer 

pH 7 ± 0.2 

25±2o

C 

40°N sunlight 

1.8 days 

(SFO) 

49011977a 

Natural Water Supplemental

pH 7.1 

25±2o

C 

40°N sunlight 

1.4 days 

(SFO) 

Soil Photolysis 

UK Silt Loam 

pH 6.4 

20±2o

C 

Dry Soil 

293 days 

(DFOP) 

Moist Soil¥

354 days 

(SFO) 

49011978b 

Supplemental

Aerobic Soil Metabolism†

ND Loamy Sand 

pH 7.8 

20±2°C 

1.1% OC 

46 days 

(IORE) 

49011981c 

Supplemental

German Sandy Loam 

pH 8.4 

20±2°C 

1.1% OC 

24.5 days 

(IORE) 

49011982c 

Supplemental

UK Silt Loam 

pH 7.5 

20±2°C 

2.2% OC 

50.6 days 

(DFOP) 

UK Sand 

pH 8.3 

20±2°C 

0.8% OC 

66.2 days 

(IORE) 

Anaerobic Soil Metabolism 

ND Sand 

pH 7.1 

20±2°C 

1.1% OC 

572 days 

(SFO) 

49011985d 

Supplemental 
Page 23 of 27

Study System Details Representative Half-Life* 

(Kinetic Equation) MRID 

Aerobic Aquatic Metabolism 

UK, Calwich Abbey Lake

pH 7.9 

20±2°C 

4.8% OC 

173 days 

(SFO) 

49011986b 

Supplemental UK, Swiss Lake 

pH 6.4 

20±2°C 

0.8% OC 

108 days 

(SFO) 

Anaerobic Aquatic Metabolism 

ND, Goose River 

pH 7.8 

20±2°C 

3.1% OC 

Stable 

(1,307 days, SFO) 

49011987b 

Supplemental ND, Golden Lake 

pH 8.2 

20±2°C 

1.0% OC 

Stable 

(1,944 days, SFO) 

* Representative half-lives are estimated SFO half-lives from a degradation curve that does not necessarily follow 

the SFO equation. Representative half-life values were calculated using nonlinear regression and SFO, DFOP, or 

IORE degradation kinetics equations. The equations can be found in the document, Standard Operating Procedure 

for Using the NAFTA Guidance to Calculate Representative Half-life Values and Characterizing Pesticide 

Degradation (US EPA. 2012). Representative half-life values calculated in this table do not include unextracted 

residues, as exhaustive extraction methods were used in the studies. Note that one aerobic soil metabolism half-life 

calculated for total toxic residues is longer than those calculated for the parent compound, and thus not comparable 

to the half-life calculated for the parent compound. This is an artifact of selecting amongst multiple degradation 

kinetics equations. In general, half-lives for the parent and total toxic residues were comparable when using the 

same equation. 

¥ Representative half-lives for moist soil photolysis were corrected for the moist dark control, which has a DT50 of 

312 days (IORE) and a stable representative half-life (285,000 days, IORE). 

† Representative half-lives for the ND Loamy Sand (MRID 49011981) include both benzene and thiophene 

radiolabeled compounds. The half-life for the benzene ring only is 47.9 days (IORE) and the half-life for the 

thiophene ring only is 44.1 days (IORE). Only the benzene ring was radiolabeled for tests conducted on the three 

other soils (MRID 49011982). 

a 4HP and PPA formation was not observed in the aqueous photolysis study. 

b A formation and decline pattern was not observed for all degradates included in the representative half-life 

calculation. 

c

 Degradates included in the representative half-life calculation peak and decline within the duration of the study 

period. For the UK Silt Loam in MRID 49011982, there is some uncertainty as the decline was only observed on 

the last sample date. 

d

 PPA is included in the representative half-life calculation, although it is unclear whether PPA concentrations are 

increasing or decreasing at study termination. 
Page 24 of 27

Table A4. Summary of Terrestrial Field Dissipation Study Results For Isofetamid¤ 

MRID 

(Year) 

Study Site, 

Crop, and 

Application 

Rate¥

% Carryover of 

Residues DT50* DT90*

Max Concentration 

in Soil (mg/kg-soil)

Max Depth 

detected 

Parent 4HP 

49011993 

(2010) 

Northwood, ND, 

USA 

Bare ground - 

sandy loam 

3 apps: 752, 755 

and 745 g a.i./ha 

9.3% - isofetamid, 0% - 

4HP 

at 359 days after last 

application 

6.98 days 

(IORE) 

126 days 

(IORE) 

0.589 

0-15 

cm 

0.013 

0-15 cm 

49018438 

(2010) 

Aberdeen, SK, 

Canada 

Bare ground - 

clay loam 

3 apps: 767, 724 

and 716 g a.i./ha 

46% - isofetamid, 0% - 

4HP 

at 301 days after last 

application 

8.7% - isofetamid, 0% - 

4HP 

at study termination, 709 

days after last 

application 

217 days 

(polynomial 

regression) 

990 days 

(polynomial 

regression) 

0.543 

0-15 

cm 

0.025 

0-15 cm 

49018441 

(2011) 

Proctor, AR, 

USA 

Bermuda 

Turfgrass grown 

on silt loam 

8 apps: 509 g 

a.i./ha 

28.6% - isofetamid (0-8 

cm), 

0% - 4HP (0-8 cm) 

at 120 days after last 

application 

35 days 

(SFO) 

Not 

Calculated 

0.0789 

8-15 

cm 

0.0104 

0-8 cm 

49011992 

(2010) 

Kerman, CA, 

USA 

Bare ground - 

loamy sand soil 

3 apps: 746, 731 

and 749 g a.i./ha 

3% isofetamid (0-15 cm) 

at 365 days after last 

application 

46.5 days 

(SFO) 

155 days 

(SFO) 

0.515 

15- 30 

cm 

No 

Detections 

49018442 

(2011) 

Goldsboro, NC, 

USA 

Fescue Turfgrass 

grown on sandy 

loam 

8 apps: 509 g 

a.i./ha 

37% - isofetamid (0-8 

cm), 

38% - 4 HP (0-8 cm) 

at 119 days after last 

application 

29 days 

(SFO) 

Not 

Calculated 

0.112 

15-30 

cm 

0.015 

8-15 cm 

¤ Turf Dissipation Studies also analyze thatch for degradates 4HP and GPTC. Thatch results are not reported in this 

table. 

¥ Formulation applied in each study is a suspension concentrate 

* DT50s and DT90s are from PMRA Data Evaluation Reviews. 

Table A5. Summary of maximum amount of transformation products observed in fate studies. 
Page 25 of 27

Compound 

Maximum % of Applied Radioactivity Associated with Degradate (Day of Peak) 

Maximum Amount Detected at Final Sampling Interval in Corresponding Study, 

Radiolabel, and for Hydrolysis, pH (Day of Study Termination) 

Hydrolysis 

Soil 

Photolysis 

Aerobic Soil 

Anaerobic 

Soilb

Aqueous 

Photolysis 

Aerobic Aquatic 

Anaerobic 

Aquatic 

Observed in 

Field 

Dissipation 

Isofetamid 

93.3 (0) 98.7 (0) 100.3 (0) 69.9 (30) 97.0 (0) 97.0 (0) 107.8 (7) 

Yes 95.2 (5) 72.6 (30) 24.0 

(120) 

60.9 

(150) ND (30) 52.0 (100) 

82.7 

(365) 

4HP 3.7 (21) 10.4 (30) 10.3 

(150) 7.6 (100) 2.5 (365) Yes 

 2.7 (30) 6.0 (120) same same same 

PPA 2.0 (30) 4.4 (30) 2.0 (150) 11.8 

(100) 3.3 (365) 

N/A 

 same ND (120) same same same 

IBA 6.2 (30) ND (all) 0.4 (150) 80.8 (10) 7.5 (59) 1.0 (59) 

 same ND (120) same 73.9 (30) 0.5 (100) 0.3 (365) 

3-MTCAM 5.5 (14) 0.5 (14) 0.9 (30) 0.7 (0) 0.9 (0) 

 5.0 (30) ND (120) ND (150) ND (100) ND (365) 

3-MCTA 2.0 (21) 2.4 (59) 0.6 (120) 1.5 (59) 0.7 (7) 

 1.0 (30) 0.5 (120) 0.5 (150) 0.9 (100) ND (365) 

Polar 

Compound 

 66.8 (20) 

 64.3 (30) 

UnkAnS01 1.3 (60) 

 0.4 (150) 

UnkAE02 4.0 (92, 

120) 

 same 

UnkSP01 2.6 (30) 

 same 

Largest 

Unknown 

 2.0 (30) 6.0 (92) Not 

Reported 

8.0 (10) Not 

Reported same 2.9 (120) 4.7 (30) 

Total Other 

Unknowns 

0.5 (0) 7.0 (30) 12.0 (92) 6.3 (150) 13.1 (2) 20.2 

(100) 5.8 (365) 

ND (5) same 11.4 

(120) same 11.9 (30) same same 

Unextracted 

Residues 

 10.5 (30) 55.4 

(92)a

14.8 

(120) 9.7 (100) 11.6 

(365) 

 same 

53.6 

(120)a

14.7 

(150) same same 

ND=not detected 

a

 Only one sample was available for analysis at the end of this study; typically there are replicates. 

b

 In this study, the test system was aerobic from days 0-30 and flooded on day 30. 

 
Page 26 of 27

Appendix B. SWCC Output for Low-Growing Strawberries – California Strawberry 

(RLF) Scenario 

Variable Volume Water Model, Version 0.0 

 

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

Performed on: 6/ 5/2014 at 16:28 

 

Peak 1-in-10 = 105. ppb 

Chronic 1-in-10 = 30.5 ppb 

Simulation Avg = 18.0 ppb 

4-day avg 1-in-10 = 102. ppb 

21-day avg 1-in-10 = 90.9 ppb 

60-day avg 1-in-10 = 74.1 ppb 

90-day avg 1-in-10 = 64.6 ppb 

 

Benthic Pore Water Peak 1-in-10 = 51.8 ppb 

Benthic Pore Water 21-day avg 1-in-10 = 51.6 ppb 

Benthic Conversion Factor = 20.0 -Pore water (ug/L) to (total mass, ug)/(dry sed mass,kg) 

Benthic Mass Fraction in Pore Water = 0.185E-01 

 

YEAR Peak 4-day 21-day 60-day 90-day Yearly Avg Benthic Pk Benthic 21-day 

 1 5.27E+01 5.09E+01 4.73E+01 3.94E+01 3.43E+01 1.54E+01 2.50E+01 2.49E+01 

 2 6.63E+01 6.47E+01 5.96E+01 4.82E+01 4.21E+01 2.05E+01 3.40E+01 3.39E+01 

 3 1.24E+02 1.20E+02 1.07E+02 8.51E+01 7.35E+01 3.30E+01 5.50E+01 5.48E+01 

 4 6.70E+01 6.53E+01 5.98E+01 4.79E+01 4.18E+01 1.95E+01 3.37E+01 3.36E+01 

 5 3.35E+01 3.26E+01 3.09E+01 2.62E+01 2.36E+01 1.18E+01 1.99E+01 1.98E+01 

 6 6.21E+01 6.01E+01 5.47E+01 4.45E+01 3.86E+01 1.79E+01 2.97E+01 2.96E+01 

 7 1.49E+02 1.44E+02 1.30E+02 1.07E+02 9.35E+01 4.21E+01 6.92E+01 6.90E+01 

 8 1.08E+02 1.04E+02 9.24E+01 7.50E+01 6.53E+01 3.08E+01 5.24E+01 5.22E+01 

 9 7.97E+01 7.77E+01 7.50E+01 6.64E+01 5.88E+01 2.75E+01 4.65E+01 4.64E+01 

 10 6.23E+01 6.04E+01 5.71E+01 4.94E+01 4.39E+01 2.05E+01 3.50E+01 3.49E+01 

 11 1.79E+01 1.75E+01 1.63E+01 1.46E+01 1.44E+01 7.70E+00 1.28E+01 1.28E+01 

 12 1.99E+01 1.93E+01 1.76E+01 1.49E+01 1.31E+01 6.33E+00 1.08E+01 1.07E+01 

 13 6.73E+01 6.57E+01 6.14E+01 5.68E+01 5.04E+01 2.36E+01 3.83E+01 3.82E+01 

 14 2.58E+01 2.51E+01 2.44E+01 2.24E+01 2.12E+01 1.09E+01 1.83E+01 1.83E+01 

 15 7.75E+01 7.59E+01 7.00E+01 5.55E+01 4.79E+01 2.16E+01 3.57E+01 3.56E+01 

 16 2.57E+01 2.50E+01 2.25E+01 1.84E+01 1.64E+01 9.01E+00 1.53E+01 1.52E+01 

 17 2.35E+01 2.28E+01 2.21E+01 2.07E+01 1.96E+01 1.00E+01 1.57E+01 1.57E+01 

 18 7.02E+01 6.80E+01 6.13E+01 5.27E+01 4.77E+01 2.29E+01 3.74E+01 3.73E+01 

 19 6.95E+01 6.75E+01 6.29E+01 5.56E+01 5.14E+01 2.51E+01 4.15E+01 4.14E+01 

 20 4.98E+01 4.88E+01 4.51E+01 4.04E+01 3.77E+01 1.86E+01 3.11E+01 3.10E+01 

 21 7.89E+01 7.68E+01 6.87E+01 5.55E+01 4.84E+01 2.20E+01 3.70E+01 3.69E+01 

 22 5.98E+01 5.82E+01 5.22E+01 4.73E+01 4.50E+01 2.23E+01 3.65E+01 3.63E+01 

 23 8.25E+01 8.07E+01 7.67E+01 6.46E+01 5.64E+01 2.57E+01 4.33E+01 4.32E+01 

 24 1.56E+01 1.53E+01 1.42E+01 1.32E+01 1.23E+01 6.24E+00 1.20E+01 1.19E+01 

 25 4.47E+01 4.32E+01 3.79E+01 3.01E+01 2.60E+01 1.21E+01 2.01E+01 2.00E+01 

 26 4.39E+01 4.32E+01 4.15E+01 3.58E+01 3.15E+01 1.53E+01 2.56E+01 2.55E+01 

 27 4.33E+01 4.19E+01 3.73E+01 2.98E+01 2.65E+01 1.34E+01 2.26E+01 2.25E+01 

 28 3.50E+01 3.39E+01 3.24E+01 2.65E+01 2.30E+01 1.10E+01 1.85E+01 1.85E+01 

 29 2.04E+01 1.98E+01 1.76E+01 1.54E+01 1.41E+01 7.02E+00 1.19E+01 1.18E+01 

 30 2.50E+01 2.44E+01 2.18E+01 2.00E+01 1.84E+01 8.89E+00 1.47E+01 1.47E+01 

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

******* 

 Effective compartment halflives averaged over simulation duration: 
Page 27 of 27

 

 washout halflife (days) = 141.480147244749 

 water col metab halflife (days) = 260.299287554702 

 zero hydrolysis 0 

 photolysis halflife (days) = 239.202201470900 

 volatile halflife (days) = 69021186.4615431 

 total water col halflife (days) = 66.2671240265854 

 

 zero burial 0 

 zero benthic metab 0 

 zero benthic hydrolysis 0 

 zero benthic total degradation 0 

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

 Fractional Contribution of Transport Processes to Waterbody & Total Mass (kg): 

 

 Due to Runoff = 0.8194 239.3 

 Due to Erosion = 0.0000 0.1352E-01 

 Due to Drift = 0.1806 52.72 

 ******* Inputs ******* 

 491.0 = oc partitioning coefficient 

 166.5 = water column half Life 

 20.00 = reference temp for water column degradation 

 0.000 = benthic Half Life 

 20.00 = Reference temp for benthic degradation 

 2.000 = Q ten value 

 1.800 = photolysis half life 

 40.00 = reference latitude for photolysis study 

 0.000 = hydrolysis half life 

 359.5 = molecular wt 

 0.4400E-10 = vapor pressure 

 5.330 = solubility 

 0.1728E+07 = field area 

 0.5260E+05 = water body area 

 2.740 = initial depth 

 2.740 = maximum depth 

 3 1=vvwm, 2=usepa pond, 3 = usepa reservoir, 4 = const vol no flow, 5 = const vol w/flow 

 F T = burial, else no burial 

 0.1000E-07 = mass transfer coefficient 

 0.5000 = PRBEN 

 0.5000E-01 = benthic compartment depth 

 0.5000 = benthic porosity 

 1.350 = benthic bulk density 

 0.4000E-01 = OC frcation in benthic sediment 

 5.000 = DOC in benthic compartment 

 0.6000E-02 = benthic biomass 

 1.190 = DFAC 

 30.00 = SS 

 0.5000E-02 = chlorophyll 

 0.4000E-01 = OC frcation in water column SS 

 5.000 = DOC in water column 

 0.4000 = biomass in water column