1

OFFICE OF CHEMICAL SAFETY

AND POLLUTION PREVENTION

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

June 17, 2015

PC Code: 098301

MEMORANDUM DP Barcode: 427697

SUBJECT: Aldicarb: Drinking Water Exposure Assessment for Preliminary Risk 

Assessment

FROM: Edmund Wong, Environmental Chemist

ERB2/EFED (7507P)

THROUGH: R. David Jones, Senior Agronomist

Brian Anderson, Branch Chief

ERB2/EFED (7507P)

TO: Susan Bartow, Chemical Review Manager

Kevin Costello, Acting Branch Chief

Risk Management and Implementation Branch 4

Pesticide Re-Evaluation Division (7508P)

William Donovan, Chemist

Matthew Lloyd, Risk Assessor

Mike Metzger, Branch Chief

RAB4/HED (7509P)

This Environmental Fate and Effects Division (EFED) memorandum is a drinking water 

exposure assessment for the registration review of aldicarb. Aldicarb may be used on cotton, dry 

beans, peanuts, soybean, sugar beets, and sweet potatoes. This assessment provides estimated 

drinking water concentrations (EDWCs) for the total toxic residues (TTR) including aldicarb and 

two structurally similar degradates, aldicarb sulfoxide and aldicarb sulfone. Tier II surface water 

EDWCs were estimated with the Surface Water Concentration Calculator (SWCC). The 

Pesticide Root Zone Model-Groundwater (PRZM-GW) was used to estimate groundwater 

EDWCs at a pH of 6. TTR degradation varies across pH; therefore, slight acidic conditions 

yielded the highest concentration of aldicarb TTR in groundwater. Available monitoring data 

were also evaluated, however, the monitoring studies were non-targeted. Thus, these data are not 

expected to provide an upper bound estimate of the potential exposure to aldicarb TTR and it is 

recommended that the Health Effects Division adopt the EDWC generated from the modeling in

this assessment. Surface water and groundwater monitoring data indicated that aldicarb and its 

degradates were monitored since February 1986 to December 2014. Based on the analysis of the 

data, even with the mitigation implemented in 2009, there is no discerning trend of decline in 

concentrations in groundwater.
2

The groundwater EDWCs are less than those for surface water; therefore, it is 

recommended that the EDWCs for surface water be used in future assessments conducted by the 

Health Effects Division. The highest one-in-ten year peak, annual mean, and 30-year mean

EDWCs (187, 16, and 5.3 μg/L, respectively) are based on the labeled use of aldicarb on sugar 

beets at 4.05 lbs a.i./acre per year. Please note that the application rates for modeling inputs on 

SWCC and PRZM-GW are different due to application instructions on the label. Application rate 

for PRZM-GW was based on the highest application rate that is allowed for labeled use in sugar 

beets but the granules have to be covered with soil or drilled to a specified soil depth. 

Meanwhile, the application rate used for SWCC modeling was the highest rate for sugar beets 

that can be applied without soil cover, which significantly increases the risks of surface water 

exposure. Results are summarized in Table 1.

Table 1. Screening-Level TTR EDWCs for Proposed Uses of Aldicarb A

Source (Model) Use Site

(Max. Annual App. Rate)

1-in-10-year 

30-Year Mean

Peak (μg/L) Annual Mean

(μg/L)

Surface water 

(SWCC) Sugar beets (4.05 lbs a.i./A)B 187 16 5.3

Peak Post-Breakthrough Average

Ground water 

(PRZM-GW) (pH 6) Sugar beets (4.95 lbs a.i./A)B 93.2 40

A Maximum values in bold.

B Application rates are different for both surface and ground water modeling because application instructions on the label

specified that the 4.95 lbs a.i./A rate is covered with soil, thus minimizing surface runoff exposure, while 4.05 lbs a.i./A is the 

highest application rate that can be applied over irrigation furrow without soil cover, which increases potential surface water 

exposure.

Label Clarification:

There are some uncertainties in this assessment due to label ambiguities. The vague application 

instructions on the MEYMIK 15G product label are listed in the following table. The ambiguities 

of the instructions highly influenced the model input of the SWCC parameters and resulted in 

which crop was modeled, as well as the labeled application use rate. There would be less 

uncertainty in the exposure assessment if the label application instructions were clarified or clearly 

worded to eliminate confusion. 

Instruction Issues Description Crop Uses Pages

“Apply granules in the seed 

furrow and immediately cover 

with soil by mechanical means”

No specification of the depth 

of soil needed to cover the 

granules or the depth of the 

application

Cotton,

Dry Beans,

Peanuts,

Soybeans

At Planting 

(Aphids, 

Fleahoppers, 

Nematodes, 

Seedcorn 

maggot, 

Thrips)

7, 9, 

10, 12

“Apply granules in a 4 to 6-inch 

band (T-Band) over open seed 

furrow and immediately cover 

No specification of the depth 

of soil needed to cover the 

granules and no specification 

Cotton Nematodes 7
3

with soil by mechanical means” on the time of application

“Apply in seed furrow and 

cover with soil”

No specification of the depth 

of soil needed to cover the 

granules and no specification 

on the time of application

Cotton Aphids 7

“Side dress granules in a furrow 

that is 6 to 10 inches to one or 

both sides of plant row to a 

depth of 2 to 3 inches. Adjust 

applications to minimize root 

pruning”

No instruction on whether to 

cover the granules with a 

given depth of soil

Cotton Side Dress

(except 

California)

7

“Apply granules in a 4 to 6-inch 

band and immediately cover 

with soil by mechanical means. 

Plant into treated zone”

No specification of how 

much soil is needed to cover 

the granules or the depth of 

the application

Dry Beans,

Peanuts,

Soybeans,

Sugar Beets

At Planting / 

Split 

Application

9, 10, 

12, 13

“Where furrow irrigation is 

used, apply granules 3 to 4 

inches deep and 3 inches from 

seed row on the water furrow 

side”

The depth of soil or 

irrigation needed to 

incorporate the granules is 

not provided.

Dry Beans At Planting 9

“Apply granules in a 2 to 3 inch 

band over seed row and 

immediately cover with soil by 

mechanical means”

No specification of the depth 

of soil needed to cover the 

granules or the depth of the 

application

Sugar Beets At Planting 

(Sugar beet 

root maggot)

13

“Where furrow irrigation is 

employed side-dress granules 4 

to 8 inches to water furrow side 

of plant row at furrow depth. 

Irrigate soon after application. 

Apply within 60 days after 

planting”

Instructions indicated no soil 

cover and thus expose 

granules to terrestrial 

animals or surface runoff 

after irrigation or 

precipitation event

Sugar Beets Post 

Emergence

14
4

1. Use Characterization

Aldicarb is an insecticide, acaricide, and nematicide that is applied as granules during atplanting and/or post-emergence and in various application methods including planting in seed 

furrow, side dress, T-Band, and into plant canopy. There is currently only one end use product 

label for aldicarb, Meymik® brand 15G (Reg. No. 87895-1) which was registered in December, 

2011. There are six crops listed for use of aldicarb on the Meymik label: cotton, dry beans, peanuts, 

soybeans, sugar beets, and sweet potatoes. Table 2 lists the use pattern of maximum exposure for 

the labeled uses of aldicarb. Only ground applications are permitted. Well-setbacks are required 

including a 50 ft well-setback for use in ID, OR, WA; 300 ft well-setback for vulnerable soils in 

CO; 500 ft well-set back for vulnerable soils in MT, NE, WY. A list of the vulnerable soils 

provided on the Meymik 15G label is attached in Appendix C.

Table 2. Maximum Use Patterns for Labeled Aldicarb Use

Use

Max. Single App. 

Rate

(lbs a.i./A)

Max. Annual 

App. Rate 

(lbs a.i./A)

Min.

App. 

Interval 

(d)

App. Method Labeled Use 

States

Cotton C

1.05 (At Planting)

0.75 (Side Dress)

2.1 (Side Dress)*

1.8 A

3.15* A 21

at-plant: in furrow and Tband

post-emergent: in furrow

U.S.

*[CA only]

Dry Beans 2.1 2.1 A 0 at-plant: in furrow CO, ID, MI, OR, 

WA only

Peanuts B 1.05 (At Planting)

1.5 (Post-Emergence) 2.55 A 14

at-plant: in furrow, 

incorporated band or Tband

post-emergent: banded 

over foliage

U.S.

[Split application 

only in AL, FL, 

GA, NC, OK, TX, 

VA]

Soybeans 1.05 1.05 A 0 at-plant: in furrow or Tband

GA, NC, SC, VA

only

Sugar Beets D

4.95 (At Planting)

3.0 (Post-Emergence)

4.05 (Post-Emergence)

2.1 (At Planting)*

2.1 (Side Dress)*

4.95 A

4.2* A 14

at-plant: in furrow, 

incorporated band or Tband

post-emergent: in furrow, 

incorporated side band or 

side dress

[CO, ID, MT, NE, 

OR, WA, WY 

only]

*[CA only]

Sweet Potatoes E 3.0 3.0 A 0 pre-plant or at-plant: band 

covered by hilling LA, MS only

A Labeled use directions provide a seasonal application rate limit that approximates an annual limit. B Post-emergent applications must be irrigated immediately after application. Post-emergent applications must be 

made to dry foliage.

C Second application is restricted to 0.75 lb and must be placed in furrow at least 2 inches deep. Applications must 

be between March 1 and September 1 in California. D Applications must be made within 60 days of planting.

E Application must be made with positive displacement applicators.

2. Previous Drinking Water Exposure Assessments
5

There have been a number of drinking water exposure assessments for aldicarb. In addition, 

aldicarb was a component of the cumulative risks assessment, which considered all the N-methyl 

carbamate pesticides (Health Effects Division, 2005; OPP, 2007). Drinking water assessments 

conducted since 1999 are summarized below. Estimated drinking water concentrations have varied 

considerably across different assessments based on the available data, approved models, and 

labeled use patterns.

In 1999, a drinking water assessment was completed that provided estimates of aldicarb in ground 

water based on monitoring data, which had been summarized and analyzed by the registrant and 

model EDWC for surface water (Dutta, 1999). The maximum surface water EDWC as calculated 

by GENEEC was 88.5 μg∙L-1

. Maximum concentrations detected in monitoring data in ground 

water by region ranged from no detections in the Southwest to 187.2 μg∙L-1 in New England. The 

GENEEC results were further refined in a separate assessment using PRZM-EXAMS modeling, 

which calculated EDWCs for cotton, potatoes, and citrus. Citrus had the highest EDWCs with a 

1-in-10-year peak EDWC of 2.3 μg∙L-1 (DP 247759).

Surface water estimates were updated again in the Re-Registration Eligibility Decision (RED) (DP 

246901). EDWCs were calculated for citrus in Florida, potatoes in Idaho, and cotton in 

Mississippi. In this assessment, the highest 1-in-10-year peak EDWC was for Idaho potatoes with 

17.4 μg∙L-1. The ground water assessment was the same as that presented in the previous 

assessments.

The drinking water assessment in the 2003 EFED RED chapter was updated in 2005 (DP 316754). 

This update included an assessment of surface-water source drinking water using the total toxic 

residues method (TTR) for estimating the exposure from aldicarb, aldicarb sulfoxide and aldicarb 

sulfone combined. For surface water, 3 crops were assessed: cotton, potatoes, and citrus. Cotton 

had the highest 1-in-10-year peak EDWC with 14.6 μg∙L-1

. For ground water, SCI-GROW 

estimates were calculated for the same 3 crops, with citrus having the highest EDWC at 4.95 μg∙L1

. The ground water monitoring data were reassessed and some newer data were added to previous 

assessments. These newer data showed that concentrations in ground water in excess of 20 μg∙L-1

were being found in the early 1990s.

The drinking water exposure assessment for aldicarb was updated in 2006 (DP 333309). This 

assessment included aldicarb sulfoxide and sulfone as well as parent aldicarb. This was done to be 

consistent with the N-methyl carbamate cumulative assessment. Typical use rates were assessed 

rather than maximum label rates. Both surface and ground water sources were assessed. A refined

modeling approach was used for both ground water and surface water. Peanuts, cotton, citrus and 

potatoes were the uses assessed. For ground water, well setback distances were estimated using a 

high-end estimate of lateral ground water movement. The maximum EDWCs were for citrus in 

Florida for surface water with 10.2 μg∙L-1 for a 30 year maximum concentration and for peanuts 

in Georgia for ground water with 6.5 μg∙L-1 for a 30 year maximum concentration with a 30 ft 

buffer in place around the well.

Aldicarb was considered as part of two cumulative risk assessments for the N-methyl carbamate 

insecticides. A preliminary assessment (Health Effects Division, 2005) included aldicarb, carbaryl, 

carbofuran, formetenate, methomyl, oxamyl, propoxur, methiocarb, pirimicarb, and thiodicarb. 

The assessment looked at three routes of exposure; dietary from food, dietary from drinking water, 

and residential exposure. 
6

The drinking water component of the preliminary assessment focused on areas where combined 

N-methyl carbamate (NMC) exposure is likely to be among the highest within each region as a 

result of total NMC usage and vulnerability of drinking water sources. This analysis was based on 

a probabilistic modeling approach that considers the full range of data. Exposures in drinking water 

to individuals were incorporated into the cumulative exposure assessment on a regional- and 

source water-specific basis (i.e., ground water and surface water, by region). The regional drinking 

water exposure assessments are intended to represent exposures from vulnerable drinking water 

sources resulting from typical NMC usage and reflect seasonal variations as well as regional 

variations in cropping and NMC use. In most of the country, NMC residues in drinking water 

sources are at levels that are not likely to contribute substantially to the multi-pathway cumulative 

exposure. However, it was found that NMC residues estimated for vulnerable private wells in some 

areas of Florida (primarily along the central ridge) and the southeastern coastal plain are major 

contributors to the cumulative NMC exposures.

The revised N-methyl carbamate cumulative assessment (OPP, 2007) reflected some changes 

due to updates in the fate and transport data for some compounds due to the completion of the 

single chemical assessments, but also reflected changes in use patterns that had been 

implemented or were expected to occur as a result of the re-registration process. These included 

restrictions on the use of aldicarb in Florida and the Atlantic Coastal Plain to protect ground 

water, the expected cancellation of carbofuran and the restrictions of the use of other N-methyl 

carbamates. The methods used in the revised assessment were essentially the same as those used 

in the preliminary assessment. This assessment that cumulative risks were below levels of 

concern if carbofuran was cancelled and certain uses for pesticides other than aldicarb were 

removed (e.g., methomyl on grapes).

The current assessment reflects use directions on the only registered label for aldicarb and 

utilizes the current risk assessment methods and models.

3. Environmental Fate Characterization

Aldicarb degrades to aldicarb sulfone and aldicarb sulfoxide, primarily by aerobic soil 

metabolism (parent half-lives range from 1 to 28 days in a variety of soils). Aerobic soil 

metabolism half-lives for the combined residues (i.e., aldicarb, sulfoxide, sulfone) range from 11 

to 136 days, with a 90th percentile upper bound on the mean of 55 days. This is within the range 

observed in published field studies, where dissipation half-lives for total toxic residues ranged 

from approximately 0.3 to 5 months in the unsaturated zone, and 1 to 36 months in the saturated 

zone (Jones and Estes, 1995). 

Aldicarb is relatively stable to hydrolysis, slowly hydrolyzing only at a pH of 9 (MRID 

00102065). Aldicarb sulfoxide hydrolyzed more quickly (t1/2 = 2 - 3 days) at pH 9 than at pH 7 

(about 6% at 28 days) (MRID 00102066). Aqueous photolysis rapidly degraded aldicarb to oxime 

and nitrile forms (i.e. with a t1/2 of 4 days: MRID 42498201). However, this process will only be 

dominant in clear, shallow waters, and will not affect residues in the subsurface. 

Aldicarb and its degradates are highly mobile in soil. Freundlich Kads values ranged from 

0.20 to 0.60 mL/g for aldicarb (MRID 42498202), 0.17 to 0.36 mL/g for aldicarb sulfoxide (MRID 

43560301), and 0.12 to 0.22 mL/g for aldicarb sulfone (MRID 43560302). 
7

The lines of evidence from available registrant-submitted studies, published literature, and 

monitoring data indicate that the total toxic residues of aldicarb will degrade slowly in upper soil 

layer, move fairly rapidly into the subsurface (the rate of movement depending upon the 

permeability of the soil and amount of excess water that moves through the soil), and potentially 

persist in the subsurface and ground water under acidic (pH<7) conditions. The sulfoxide and 

sulfone degradates will hydrolyze rapidly in alkaline soils, so the ultimate fate in ground water 

will depend upon the pH of the soil, vadose zone, and aquifer.

Table 3 include the environmental fate data for aldicarb (parent only) and total residues

while Table 4 lists the environmental fate data of aldicarb sulfoxide and aldicarb sulfone.

Table 3. Chemical Properties and Environmental Fate Parameters of Aldicarb

Parameter Value Reference

Physical/Chemical Parameters

Molecular mass 190.26 g/mol Calculated

Vapor pressure (23°C) 6.25 x 10-6 torr MRID 4822504

Henry’s Law constant (23°C) 3.0 x 10-10 atm·m3/mol Calculated

Water solubility (pH 7, 25°C) 6,000 mg/L MRID 4822504

Octanol-water partition coefficient 

( KOW)

11.48 MRID 4822504

Persistence in Water

Hydrolysis half-life pH 5: no significant degradation @ 30 d

pH 7: no significant degradation @ 30 d

pH 9: < 10% degradation of parent @ 30 d

 T1/2 < 197 d

MRID 00102065

Aqueous photolysis half-life 4 d MRID 42498201

Persistence in Soil

Aerobic soil metabolism half-life 

[25°C]

parent only:

 NJ sandy loam: 2.3 d

 Houston clay: 11 d

 Lakeland sandy loam: 17 d

 Norwood silty clay: 12 d

 unspecified: 1 d

 Illinois silt: 6 d

 NC loamy sand: 10 d

total toxic residues:

 Houston clay: 28 d

 Lakeland sandy loam: 47 d

 Norwood silty clay: 136 d

unspecified: 44 d

MRID 44005001

MRID 00093642

MRID 45602904

MRID 45739801

MRID 00093642

MRID 45602904
8

Parameter Value Reference

Mobility

Fruendlich Adsorption 

Coefficients (Kf)

parent

 sandy loam: 0.186 L∙kg-1

 silt: 0.36 L∙kg-1

 clay: 0.6 L∙kg-1

 sand: 0.2 L∙kg-1

MRID 42498202

MRID 43560301

MRID 43560302

Table 4. Environmental Fate Parameters for Aldicarb Sulfoxide and Aldicarb Sulfone 

Fate Endpoint Aldicarb sulfoxide Aldicarb sulfone

Hydrolysis – pH 5 495 d (MRID 45592104)

Hydrolysis – pH 7 6% loss at 30 d (MRID 

00102066)

63 d (MRID 45592104)

Hydrolysis – pH 9 2.3 d (MRID 00102066) 1 da @ 25oC; 32 d @ 5oC (MRID 

45592104)

Hydrolysis in published 

literature: Lemley & Zhong, 

1983 (45602901); Hansen & 

Spiegel, 1983 (45602902); 

Lemley & Zhong, 1984 

(45602903)

Hydrolysis is sensitive to hydroxide concentration (base-catalyzed), with 

sulfone most sensitive and aldicarb least (Lemley & Zhong, 1983).

Aldicarb hydrolysis rates increase at pH levels >7.5; sulfoxide and 

sulfone hydrolyze more readily and are affected by pH and temperature 

(results for 5, 15 o

C) (Hansen & Spiegel, 1983).

Both pH and temperature dependence seen in hydrolysis of all 3 

chemicals. Rates for sulfone at 25 o

C 60 d @ pH7, 6 d @ pH8 (Lemley & 

Zhong, 1984)

Aqueous photolysis 123 d (12 hr light/dark) 

(MRID 45592105)

Aerobic soil metabolism 

(MRID 44005001)

Concentrations fluctuated 

between 9-86% of applied from 

7-60 day post treatment

Concentrations fluctuated between 3-

80% of applied from 7-60 day post 

treatment

Aerobic soil metabolism 

range (MRID 00101934)

Total carbamate residues (parent, sulfoxide, sulfone) 11 – 110 d in 2 soils 

x 3 pH x 2 moisture contents; avg 34 d; 90% upper confidence bound 48 

d 

Aerobic soil metabolism 5 d (MRID 45592108) 3.33 d half-life (pH 6.7 soil)

(MRID 00053370)

Total carbamate residues (parent, sulfoxide, sulfone)

28, 47, 136 for 3 soils

(MRIDs 00093642, 00080820, 00093640, 00053366)

Lab studies of all 3 forms 

(Lightfoot et al, 1987; Bank 

& Tyrrell, 1984) A

Combined residues (aldicarb, sulfoxide, sulfone) degraded to oximes, 

nitrile with half-lives up to 3 months; soil-catalyzed hydrolysis, not 

aerobic metabolism was driving factor.

Lightfoot et al, 1987 (MRID 

45602904)

Combined (parent+degradate): 44 (unsterilized) – 10 (sterilized) d surface 

soil

123 (unsterilized) – 16 (sterilized) d subsurface soil
9

Aerobic soil metabolism, 

2002 registrant submissions

(MRID 45739802)

15.2 d in IL silt (pH 7.9); 91.2 d in 

NC loamy sand (pH 6.2). 

Aerobic soil metabolism 

literature (Smelt et al, 1983)

sulfone & sulfoxide half-lives in Dutch subsoils from 2-131 d under 

anaerobic cond., 84-1100 d under aerobic condition

Aerobic aquatic metabolism, 

2002-3 registrant 

submissions 

5 d (total system) in pH 7.0 

water / pH 6.3 sediment (MRID 

45592108)

3.5 d (total system) in pH 7.0 water / 

pH 6.3 sediment (MRID 45592109)

Anaerobic aquatic 

metabolism

3.4 d (MRID 45592110) 3.5 d (MRID 45592111)

Published field studies 

(Jones & Estes, 1995)

Summarized results of 32 field studies for aldicarb in 24 locations. Halflife of total carbamate residues (aldicarb, sulfoxide, sulfone) in surface 

soil ranged from 0.3 to 3.5 months; mean 1.3 mo (40 d) & 90% upper 

confidence bound on mean 1.5 mo (45 d). In 2 studies, estimated 

subsurface half-life of 5 months.

Fruendlich Adsorption 

Coefficients (Kf)

(MRID 42498202, 

43560301, 43560302)

aldicarb sulfoxide (L∙kg-1):

 Tujunga loamy sand: 0.22 

 Wedowee sandy loam: 0.17 

 Huntington silt loam: 0.26 

 Huntington sandy clay loam: 0.26 

aldicarb sulfone (L∙kg-1):

 Tujunga loamy sand: 0.09 

 Wedowee sandy loam: 0.12 

 Huntington silt loam: 0.22 

 Huntington sandy clay loam: 0.22 

A Study looks at degradation of aldicarb and total carbamates (parent, sulfoxide & sulfone) in surface soil, soil water, distilled water, 

saturated zone soil in sterilized/unsterilized conditions

4. Exposure Modeling

The available physical/chemical and environmental fate properties of aldicarb and its 

degradates of concern were used to calculate exposure model input parameters to derive 

EDWCs.

4.1. Residues of Concern (TTR)

The aldicarb residues of concern include the parent compound and two structurally similar 

degradates: aldicarb sulfoxide and aldicarb sulfone (Health Effects Division, 2005; Reregistration 

Eligibility Decision for Aldicarb, 2007). Since both degradates exhibit similar fate characteristics 

and toxicity to that of aldicarb, a Total Toxic Residue (TTR; Ruhman, M., draft document)

approach was used for modeling exposure to all three residues. To account for total toxic aldicarb 

residues, each relevant environmental fate study (hydrolysis, aqueous photolysis, aerobic soil 

metabolism, etc.) are used to calculate the amount of aldicarb, aldicarb sulfoxide, and aldicarb 

sulfone present in each study at each sampling interval. The total concentrations are used to 

recalculate the rate constant and the corresponding half-life value for each study.

4.2. Surface Water

The TTR modeling approach was used to estimate aquatic exposure using TTR half-life 

values (from Table 4), and aldicarb soil mobility and chemical properties (from Table 3). 
10

Chemical property and environmental fate input values were chosen in accordance with current 

input parameter guidance (USEPA, 2009).

Surface water source drinking water exposure was estimated using the Tier II exposure 

model SWCC (v1.106). Chemical input parameters for SWCC follow in Table 5.

Aldicarb use on peanuts, cotton, dry beans, soybeans, and sugar beets were modeled 

considering maximum single and annual application rates, as well as minimum retreatment 

intervals. The rates and uses in corresponding states are listed on Table 2. A drinking water intake 

percent cropped area (PCA) adjustment factor of 1 was utilized in this assessment because aldicarb 

may be used on multiple crops (Brady, 2014). Regional EDWCs were derived based on HUC 2 

region drinking water intake PCAs, considering the geographic limitation of aldicarb use. The 

results are listed in Appendix B.

Aldicarb use on sweet potatoes were not modeled because the application instruction 

requires the granules to be covered to a sufficient soil depth (8-10 inches hilling or bed forming 

process) limiting runoff, thus reducing the potential surface water exposure1

. In addition, since 

drift is not expected from granular application of aldicarb, offsite exposure is expected to be 

minimal for this use.

Table 5. SWCC Chemical Input Parameters for Aldicarb TTR A

Input Parameter Value Justification Source

Kd (mL/g) 0.16 Mean value for aldicarb, its sulfoxide 

and its sulfone

MRID

42498202

43560301

43560302

Aerobic aquatic metabolism 

half-life (days) [Temp. (°C)]

12

[25]

Single acceptable guideline study for 

aldicarb TTR (4 days) x 3

MRID 

44592107

Anaerobic aquatic 

metabolism half-life (days) 24 No data; use 2X aerobic aquatic halflife Calculated

Aqueous photolysis half-life 

(days) [Ref. Latitude (°)]

4

[40]

Represents the single value for the 

residues of concern

MRID 

42498201

 1 The SWCC only considers runoff in the top 4 cm for ground applications; therefore, no runoff would result from 

modeling this scenario.
11

Input Parameter Value Justification Source

Hydrolysis half-life (days)

pH 5: 0

pH 7: 0

pH 9: 60

Represents the value for aldicarb TTR MRID 

00102065

Aerobic soil metabolism 

half-life (days)

[Temp. (°C)]

55

[25]

Represents the upper 90% confidence 

bound on the mean for combined 

aldicarb TTR half-lives from 19 soils

MRID

00102051, 

00093642, 

00080820, 

00093640, 

00053366, 

00101934, 

00035365, 

00102071

Foliar half-life (days) 0 Default value in the absence of data USEPA, 2012

Molecular mass (g/mol) 190.3 Molecular mass of aldicarb Calculated

Vapor pressure (torr)

(25°C) 6.3 × 10-6 Study value for aldicarb MRID 00152095

Solubility in water (mg/L)

(25°C) 6,000 Study value for aldicarb Acc 255979

A Source data are in Tables 3 and 4.

Use Pattern Inputs

SWCC use pattern inputs are listed in Table 6. Modeled SWCC scenarios were those 

applicable to the labeled use sites that are expected to result in the highest exposure. Maximum 

labeled application rates and numbers of applications per year along with minimum retreatment 

intervals allowed on the label were modeled. Dates of initial application were selected within the 

scenario crop season and characterized by vulnerability to runoff. The date resulting in the 

highest exposure estimates is reported. This is expected to produce high-end exposure estimates 

that are conservative.

Table 6. SWCC Scenarios and Input Parameters Describing Maximum Patterns of 

Aldicarb Use on Representative Use Sites A

Use Site 

(Labeled Use)

SWCC

Scenario

Date of 

App.

App. Rate in lbs 

a.i./A

(App. Time)

App. 

per 

Year

App. 

Interval 

(days)

CAM 

Input

PCA

(%) 

Application 

Efficiency/ 

Spray Drift

Cotton

CA cotton Apr. 4

Apr. 25

1.05 (At Planting)

2.1 (Side Dress)

2 21 1

100 0.99/0

NC cotton Sep. 1

Sep. 22 1.05 (At Planting)

0.75 (Side Dress) MS cotton Apr. 1

Apr. 22

Dry Beans

MI beans

Apr. 1 2.1 (At Planting) 1 NA 1

OR snbeans

Peanuts NC peanuts Apr. 1

Apr. 15

1.05 (At Planting)

1.5 (Post Emergence) 2 14 72
12

Use Site 

(Labeled Use)

SWCC

Scenario

Date of 

App.

App. Rate in lbs 

a.i./A

(App. Time)

App. 

per 

Year

App. 

Interval 

(days)

CAM 

Input

PCA

(%) 

Application 

Efficiency/ 

Spray Drift

Soybeans MS soybeans Apr. 1 1.05 (At Planting)

1 NA 1

Sugar Beets MN sugar beets Apr. 15 4.05 

(Post Emergence)

*NA = Not Applicable

A Source data are in Table 2.

Surface Water Results

The 1-in-10-year peak, 1-in-10-year peak annual average, and 30-year mean exposure 

estimates in surface water drinking water sources for aldicarb TTR are listed in Table 7. Model 

input and output files are attached in Appendix A. The maximum labeled use pattern on sugar

beets resulted in the highest EDWCs. These exposure estimates are adjusted by the national

PCA applicable to the use.

Table 7. SWCC Output (PCA-adjusted) for Aldicarb TTRs A

Use Site PRZM 

Scenario PCA C pH B 1-in-10-year Peak (μg/L)

1-in-10-year 

Annual 

Average

(μg/L)

30-year 

Mean (μg/L)

Cotton

CA cotton

100

7

23.1 1.75 0.45

NC cotton 51.1 3.65 1.71

MS cotton 84.1 5.64 2.18

Dry Beans

MI beans 73.1 7.35 2.68

OR snbeans 70.3 6.52 1.83

Peanuts NC peanuts 50.4 4.01 1.29

Soybeans MS soybeans 63.7 3.72 1.09

Sugar beets MN sugar beets

7 187 16 5.3

9 187 12 3.87 A Maximum values are in bold

B pH is based on the value of hydrolysis half-lives of aldicarb TTR C The PCA is the national PCA applicable to the use. 

For characterization, surface water exposure was estimated for aldicarb TTR, taking into 

account for degradates, sulfoxide and sulfone. Since degradation of aldicarb TTR is driven by 

pH-dependent hydrolysis (especially in alkaline conditions), both pH 7 and 9 hydrolysis values 

of aldicarb TTR were assessed, where hydrolysis input rate of pH 7 is 0 days (no significant 

degradation) and pH 9 is 60 days. Using sugar beets as an example, SWCC output shows similar

peak concentrations of pH 7 and 9, both at 187 μg/L. Larger differences were shown with 

annual average and 30-year average, where pH 7: 9 (16:12 μg/L) is 25% and pH 7: 9 (5.3:3.9

μg/L) is 26%, respectively. These results however, show that hydrolysis has minimal impact on 

the resulting surface water exposure estimate. 
13

4.3. Ground Water

4.3.1. PRZM-GW

PRZM-GW inputs are listed in Table 8. Aldicarb use on sugar beets were modeled because 

it has the highest application rates (Table 2). Application inputs represent the use pattern of sugar 

beets for maximum exposure, which is two applications per year, each at 2.774 kg a.i./hectare, 14

days apart. The initial date of application (April 1) is within the application season and selected 

to result in high-end concentrations in ground water due to vulnerability to precipitation.

PRZM-GW was used to simulate transport processes through high leaching potential soils 

to a shallow unconfined aquifer with a water table at 9 meters (~ 33 feet) below the surface. The 

well screen extended an additional 1 m below the water table. This assessment follows the refined 

ground water exposure approach used for the aldicarb RED (USEPA OPP EFED, 2006; USEPA 

OPP, 2007a), the N-methyl carbamate cumulative risk assessment (USEPA OPP, 2007b), the 

Drinking Water Exposure Assessment for proposed expansion of aldicarb use on potatoes into 6 

additional states (CO, MI, MN, ND, SD, WY) (USEPA OPP EFED, 2008), and the Tier 2 Drinking 

Water Assessment Tobacco Uses of aldicarb and its major degradates aldicarb sulfoxide and 

aldicarb sulfone (USEPA OPP EFED, 2009). 

The well concentration is the average pore water concentration across the length of the 

screen. PRZM was set up to deliver the average pore water concentration in the ‘saturated’ soil 

profile in the upper meter of the ground water zone. 

The modes and rates of degradation for aldicarb residues changed through the soil profile. 

The aerobic soil metabolism rate for the top 25 cm is used with linearly rate decrease with 

increasing depth to 1 m. Below that, only the rate of hydrolysis. Table 8 summarizes the pertinent 

aldicarb properties used for this assessment. These properties came from an evaluation of 

registrant-submitted studies. Properties for aldicarb represent total residue (parent aldicarb, plus 

the degradates aldicarb sulfoxide and aldicarb sulfone) properties.
14

Table 8. PRZM-GW Input Parameters for Aldicarb A

Input Parameter Value Justification Source

Application Rate

(kg a.i./ha) 2.774

Maximum labeled single split 

application rate for sugar beets: 

Meymik® brand 15G Aldicarb 

label (EPA Reg. No. 87895-1)

Meymik 15G

labeled use Applications per Year 2; every year

Maximum number of 

applications per year at the 

maximum application rate

Reapplication interval

(days) 14 Minimum labeled intervalbetween pre- and post-emergence

Initial application date Apr. 1

Selected within application

season and for high-end 

vulnerability due to precipitation

Estimated

Application Method @ Depth (# 5) As stated on label as to be 

applied at plant as granules in 

bands or furrows and then 

covered with soil for the 

estimated incorporation depth

Meymik 15G

labeled use and 

estimated depth

Incorporation Depth 

(cm) 2

Efficiency 0.99 Label stated exclusively for 

ground use only Meymik 15G

labeled use

Drift 0

Label stated that active 

ingredient and formulation are in 

granular form, thus no spray drift

Hydrolysis Half-life

(days)

495 d @ pH 5 (measured)

152 d @ pH 6 (estimated)

63 d @ pH 7 (measured)

6 d @ pH 8 (measured)

1 d @ pH 9 (measured)

Represents the value for the total 

residues of concern (TTR). 

Based on sulfone rates for 

combined degradates, below 100 

cm. Parent hydrolyzed only at pH 

9. Sulfoxide 2-3 days @ pH9

MRID 00102065

Surface Soil Half-life

(days) 55

Represents the upper 90% 

confidence bound on the 

combined parent + sulfoxide +

sulfone (TTR) half-life from 19 

soils, for the top 25 cm. 

Decreased linearly from 25 to 

100 cm.

MRID 

00102051 

00093642 

00080820 

00093640 

00053366 

00101934 

00035365 

00102071

Kd (ml/g) 0.12

KOC= 10 mL/g

Represents the value for aldicarb 

sulfone MRID 43560302

Additional Notes Modeled total aldicarb 

residues (TTR)

Half-life values used in inputs based on combined 

aldicarb + sulfone + sulfoxide residues; lowest Kd of 

the 3 chemicals used for mobility. Assumes equal 

toxicity of parent, degradates A Source data are in Tables 2, 3, and 5.
15

Hydrolysis half-life of combined aldicarb residues in groundwater was estimated based 

on aldicarb sulfone because parent compound only hydrolyzes at pH 9 and aldicarb sulfoxide 

hydrolyzes rapidly only at pH 9 but only 6% at 30 days on pH 7. Furthermore, aldicarb sulfone is 

the terminal toxic degradate of parent aldicarb and is of core concern due to its mobility and 

persistence in subsurface conditions.

EPA estimated the hydrolysis half-life at pH 6 using the measured rates at pH values of 5, 

7, and 9 and the following equations to solve for the acid- (ka), neutral- (kn) and base- (kb) 

catalyzed hydrolysis rate constants:

(1) KpH5 = ka(10-5) + kn + kb(10-9)

(2) KpH7 = ka(10-7) + kn + kb(10-7)

(3) KpH9 = ka(10-9) + kn + kb(10-5)

Once the three rate constants are determined, the overall hydrolysis rate at any pH can be 

determined using the following equation:

(4) KpHX = ka[H+] + kn + kb[OH-]

This resulted in a rate constant of 0.00456 and a T1/2 of 152 days for aldicarb sulfone at pH 6. 

Estimated aldicarb residues in ground water are based on the labeled maximum annual 

application rate of 4.95 lb ai/acre for sugar beets, applied twice (with split applications of 2.774 

lb ai/acre) during at plant and post-emergence as granules in bands or furrows and covered with 

soil. 

To account for the well setback distances specified on the Meymik 15G label, EFED used 

a plug flow model to simulate the additional travel time for a pesticide to reach a drinking water 

well from point of application. This is explained in detail in the preliminary NMC cumulative 

assessment (USEPA/FIFRA SAP, 2005). Well setback distances result in additional travel time 

for the chemical to move laterally to the well. This results in additional degradation. Reductions 

in concentration are calculated in these assessments by a plug flow approximation:





 



 = − k

v

L

C

C

exp

0

where C = concentration at well [mass/volume]

C0= concentration at point of application [mass/vol]

L = well setback distance [length]

v = lateral ground water velocity [length/time]

k = degradation rate in aquifer [time-1]

For the ground water exposure assessment, EFED used the reduction factor associated 

with several of the corresponding well-setback distances on the Meymik 15G label (50 ft for 

soils in ID, OR, WA; 300 ft for vulnerable soils in CO; 500 ft for vulnerable soils in MT, NE, 

WY). The reduction factor is based on a typical high-end lateral ground water velocity of 0.305

m/da (1 ft/da) as recommended in the PRZM-GW guidance document (USEPA. 2012b).
16

 Estimated Total Aldicarb Residues in Ground Water

PRZM-GW outputs are listed in Table 9. EFED compared the distributions of total 

aldicarb residues in groundwater over the environmentally relevant pHs of 6, 7, and 8 because 

degradation of aldicarb residues is heavily driven by pH-dependent hydrolysis in the subsurface, 

specifically in alkaline conditions. These pH ranges serves a proper representation of the 

groundwater pH scenarios in Idaho, Oregon, and Washington State. These states have a minimum 

well setback distance of 50-foot well setback was specified on the label. Despite the soil types in 

Idaho, Oregon, and Washington state being different than that of the modeled scenarios, EFED 

considers these scenarios as the best surrogates to represent vulnerable soils. 

EFED recognizes that the scenarios used in modeling aldicarb has its limitations and some 

of the soil names used in the model scenarios are listed in the Meymik label with additional 

restrictions and could be disputed for use in modeling. However, these PRZM-GW scenarios and 

soil types were developed and simulated as proxies with conservative approach to best represent 

the most vulnerable soils with high leaching potential and shallow groundwater table in order to 

account for groundwater contamination risks. 

PRZM-GW outputs for the minimum 50-foot well setback for labeled use in Idaho, Oregon, 

and Washington yielded the highest estimated concentration with FL Central Ridge scenario in the 

range of 1.62 – 93.2 μg/L and 0.0033 – 40 μg/L for maximum daily concentration and postbreakthrough mean, respectively, within the environmentally relevant groundwater pH range of 6, 

7, and 8. However, the highest mean breakthrough time is 11.9 years with the Wisconsin Central 

Sands scenario. These results should be interpreted in the context of the pH range because 

groundwater pH can vary even within the same region or aquifer. 
17

Table 9. PRZM-GW Output for Aldicarb TTRA

Use 

Crop

Modeled Scenario

(ID, OR, WA)

Well 

Setback 

(ft)

Ground

water 

pH

Max. Daily 

Conc. (μg/L)

Mean 

Breakthrough 

Time (yrs)

Postbreakthrough 

Mean (μg/L)

Sugar 

Beets

DEMARVA 50

6 54

5.5

33

7 9.3 3.5

8 3.8E-03 2.7E-05

FL Central Ridge 50

6 93.2

3.4

40

7 33.6 5.8

8 1.62 3.3E-03

FL Jacksonville 50

6 53

2.7

25

7 15.1 4.2

8 1.09 3.0E-03

GA Southern Coastal 

Plain 50

6 6.6

5.4

2.5

7 0.46 0.06

8 2.0E-07 5.8E-10

NC Eastern Coastal Plain 50

6 4.2

9.0

2.6

7 0.26 0.08

8 8.84E-05 5.9E-07

WI Central Sands 50

6 21

11.9

15.9

7 0.85 0.43

8 1.0E-06 1.9E-08 A Maximum values are in bold.

PRZM-GW outputs for varying distance of well setbacks which were specifically stated 

on the label for sugar beets use in the states of CO, MT, NE, and WY are listed in Table 10. The 

highest concentration of total aldicarb residues generated with Florida Central Ridge scenario at 

pH 6 illustrated that increasing distance in well setback resulted in significant decreased of 

aldicarb concentration. 

Table 10. Estimated concentrations of total aldicarb residues in different well setback 

distances in states specified on the label. 

Use 

Crop Modeled Scenario

Well 

Setback 

(ft)

Ground

water 

pH

Max. Daily 

Conc. (μg/L)

Mean 

Breakthrough 

Time (yrs)

Postbreakthrough 

Mean (μg/L)

Sugar 

Beets

FL Central Ridge 

(CO) 300 6 4.0 3.4 1.72

FL Central Ridge 

(MT, NE, WY) 500 6 0.32 3.4 0.14
18

Figure 1. Groundwater EDWCs (μg/L) per Time (years) for the Florida Central Ridge (pH 6)

Figure 2. Groundwater EDWCs (μg/L) per Time (years) for the Florida Central Ridge (pH 7)

Figure 3. Groundwater EDWCs (μg/L) per Time (years) for the Florida Central Ridge (pH 8)
19

Figure 1, 2, & 3 displays ground water concentrations over time for the Florida citrus scenario in 

slight acidic, neutral, and slight alkaline conditions (pH 6, 7, & 8). Figure 1 shows that under 

slight acidic condition, aldicarb TTR is persistent, hydrolyzes slowly and averaged between 50 to 

100 μg/L with a peak of ~175 μg/L over 100 simulated years. Under neutral condition (pH 7) in 

Figure 2, aldicarb TTR follows the pattern of pH 6 but with concentrations fluctuate within 10 to 

over 20 ppb with the spike of over 60 ppb. In slight alkaline conditions (Figure 3), aldicarb TTR 

hydrolyzes quickly to under 0.1 ppb but peaked at 3 ppb in a high precipitation event.

5. Modeling Results Summary

The reported EDWCs are upper bound estimates that were derived using conservative 

model input assumptions related to the environmental fate of aldicarb as well as the proposed use 

patterns. The EDWCs represent the potential exposure to aldicarb in a rural drinking water well 

beneath an agricultural field (a high pesticide use area), which draws water from an unconfined, 

high water-table aquifer that is used as source drinking water. Vulnerable groundwater supplies 

are highly localized; therefore, the EDWCs are not expected to represent actual drinking water 

concentrations resulting from the proposed use across the entire country but rather provide an 

upper bound exposure estimate for use in the new chemical dietary risk assessment that represent 

the potential exposure to a subset of the U.S. population. The USGS indicates that 14% 

(42,900,000) of the US population derives their drinking water from self-supplied sources with 

groundwater being the dominant source.1 Moreover, the EDWCs are not intended to represent the 

exposure to individuals drinking from publically supplied water that is sourced from confined 

aquifers. However, confined aquifers may be vulnerable to aldicarb contamination if natural or 

man-made preferential flow pathways exist. In addition, high-volume pumping (e.g., irrigation) in 

confined aquifers can create a significant downward hydraulic gradient between an overlaying 

unconfined aquifer and a confined aquifer. 1

Table 11 summarizes the screening-level exposure model results for aldicarb TTRs.

Table 11. Screening-Level TTR EDWCs for Aldicarb Uses A

Source (Model) Use Site

(Max. Annual App. Rate)

1-in-10-year 

30-Year Mean

Peak (μg/L) Annual Mean

(μg/L)

Surface water 

(SWCC) Sugar beets (4.05 lbs a.i./A)B 187 16 5.3

Peak Post-Breakthrough Average

Ground water 

(PRZM-GW) (pH 6) Sugar beets (4.95 lbs a.i./A)B 93.2 40

A Maximum values in bold. “N/A” means “not available.” B Application rates are different for both surface and ground water modeling because application instructions on the label 

specified that the 4.95 lbs a.i./A rate is covered with soil, thus minimizing surface runoff exposure, while 4.05 lbs a.i./A is the 

highest application rate that can be applied over irrigation furrow without soil cover, which increases potential surface water 

exposure.

6. Monitoring Data
20

Included in this assessment are available data on aldicarb, aldicarb sulfone, and aldicarb 

sulfoxide (aldicarb residues of concern) from non-targeted monitoring conducted in the 

following water monitoring programs and registrant submitted studies: the California 

Department of Pesticide Regulation (CDPR) surface water database 

(http://www.cdpr.ca.gov/docs/emon/surfwtr/surfcont.htm, the USGS NAWQA surface and ground 

water database (http://cida.usgs.gov/nawqa_queries_public/), the USEPA STORET Data Warehouse 

(http://www.epa.gov/storet/), and the Bayer CropScience monitoring studies.

6.1. USEPA STORET Data Warehouse

STORET data indicate that all 50 states in the U.S. including the District of Columbia

were monitored for aldicarb, aldicarb sulfone, and aldicarb sulfoxide at various times 

from February 1986 to December 2014. A total of 12310 samples were collected from 

7041 sites, with parent aldicarb, sulfoxide, and sulfone sample collection numbered at 

3966, 4219, and 4125, respectively. Aldicarb residues were detected in 222 samples 

with a detection percentage of 1.8% out of the total samples. The lowest range of 

detection level was 0.0009 μg/L and the highest detected concentration was 9.0 μg/L. 

6.1.1. USEPA STORET Surface Water Data

On surface water data, a total of 9,045 samples were collected for aldicarb and its 

residues. The greatest frequencies of detections for surface water were in the 

Southwestern U.S. and California. Parent aldicarb and sulfone was detected 

simultaneously in one surface water sample with a concentration of 0.5 and 0.4 μg/L, 

respectively in San Miguel County, New Mexico on August 2001. Sulfoxide was 

detected in a total of five samples with the highest concentration at 0.3 μg/L in San 

Miguel, New Mexico on August 2001. The other four samples were found within the 

range of 0.0173-0.111 μg/L between May 2004 to April 2006 in Mohave, San Diego, and 

Alameda Counties, California (U.S. Geological Survey 2015).

6.1.2. USEPA STORET Ground Water Data

A total of 3,265 samples were collected for aldicarb and its residues. The vast majority of 

detection frequencies were in the Southeastern U.S., especially in Collier County, 

Florida. Parent aldicarb was found in 151 samples from different sites in Collier County, 

except for one from Glades County, Florida. Parent aldicarb was detected twice at 62 

different sites in Collier County, Florida at the concentration of 0.18μg/L between 

February to October 2008, prior to implementation of mitigation plan. Aldicarb, aldicarb 

sulfoxide, and aldicarb sulfone were detected once in 29 different sites in Collier County, 

Florida between February to May 2012 at the concentration of 0.64, 0.30, and 0.35 μg/L, 

respectively. The earliest and highest detection of sulfoxide was measured at 2.6 μg/L in 

Yuma, AZ on January 1997. All other 29 sulfoxide samples were at 0.3 between March 

– May 2012 in Collier County, Florida. Aldicarb sulfone was first detected on January 

1997 in Yuma, Arizona with the highest concentration of 9.0 μg/L. All the subsequent 

detections of sulfone (30 samples) were in Collier County, Florida within the months of

February to May 2012 at concentration 0.35 μg/L (U.S. Geological Survey 2015).
21

6.1.3. USEPA STORET Monitoring Data Summary

Monitoring data for both STORET surface and ground water results indicated that the 

monitoring is non-targeted and while some sites were sampled twice or more than ten 

times but the overwhelming majority were sampled only once. The timing of the 

monitoring was irregular as well. Some sites were monitored for several consecutive 

years, however, many sites with detected aldicarb and residues were only sampled once 

and no follow-up monitoring. Hence, the data cannot be correlated with aldicarb use. 

6.2. USGS NAWQA Surface and Ground Water Data

NAWQA data indicate that 50 states in the U.S. and the District of Columbia except for 

Kentucky were monitored for aldicarb, aldicarb sulfoxide, and aldicarb sulfone at various times 

from May 1992 to December 2013. A total of 44298 samples were collected from 6587 sites. 

The total number of parent aldicarb, sulfoxide, and sulfone detections and percentage per total 

number sampled were 231 and 0.5%, respectively.

Parent aldicarb, sulfoxide, and sulfone detections in surface and ground water monitoring 

data are summarized in their individual sections in the following: 

6.2.1. Aldicarb

6.2.1.1. Surface Water Monitoring Data

Criteria Data

Number of Surface Water Detections 54 (8,456 Total Samples)

Lowest Surface Water Detection 0.08 μg/L (Weld County, CO; July 1994)

Highest Surface Water Detection 2.21 μg/L (Sumter County, GA; September 1993)

Earliest Detection 0.34 μg/L (Beaufort County, NC; April 1993)

Latest Detection 0.1625 μg/L (Washington County, MS; May 2005)

State County Detection 

Numbers

Concentration

(μg/L)

Collection Date

Range

AL Russell, Houston, Henry 4 0.28 - 0.37 June 1993

CA Merced 1 0.46 April 1993

CO Weld 1 0.08 July 1994

GA

Baker, Carroll, etc. (21 Counties) 41 0.26 - 0.9 Jun – Nov 1993

Cobb* 1 1.47 Nov 1993

Sumter* 1 2.21 Sep 1993

MS Washington 1 0.1625 May 2005

NJ Somerset 1 0.13 Jul 1997

NC Beaufort 1 0.34 Apr 1993

SC Orangeburg 1 0.48 May 1996

WY Big Horn 1 0.37 Apr 1999

*Location were listed specifically due to concentration over 1μg/L. Numbers are also bolded.

6.2.1.2. Ground Water Monitoring Data
22

Criteria Data

Number of Ground Water Detections 4 (6,408 Total Samples)

Lowest Ground Water Detection 0.005 μg/L (Collier County, FL; April 2009)

Highest Ground Water Detection 0.25 μg/L (Sumter County, GA; September 1993)

Earliest Detection 0.25 μg/L (Sumter County, GA; September 1993)

Latest Detection 0.005 μg/L (Collier County, MS; April 2009)

State County Detection 

Numbers

Concentration

(μg/L)

Collection Date

Range

FL Collier 1 0.005 Apr 2009

GA Sumter 1 0.25 Sep 1993

IN Delaware, Hancock 2 0.1 – 0.8 Oct 93 – Aug 94

6.2.2. Aldicarb Sulfoxide

6.2.2.1. Surface Water Monitoring Data

Criteria Data

Number of Surface Water Detections 33 (8,334 Total Samples)

Lowest Surface Water Detection 0.0009 μg/L (Hancock County, IN; July 2010)

Highest Surface Water Detection 1.91 μg/L (Madison, LA; May 1997)

Earliest Detection 0.92 μg/L (Sumter County, GA; April 1994)

Latest Detection 0.0024 μg/L (St. Mary County, LA; May 2011)

State County Detection 

Numbers

Concentration

(μg/L)

Collection Date

Range

AL Madison 14 0.0033-0.1674 Apr 2000 – Apr 2010

CA San Joaquin 1 0.0047 Feb 2002

CO Weld 1 0.98 Aug 1994

GA Sumter 1 0.92 Apr 1994

IN Hancock 1 0.0009 Jul 2010

LA Madison 4 0.5 – 1.91 May 1997

St. Mary 1 0.0024 May 2011

MS Warren, Washington 6 0.004 - 0.1009 May 2005 – Jun 2010

OR Marion 2 0.0042 - 0.008 Jun – Jul 2002

SC Orangeburg 1 1.2 May 1996

NY Suffolk 1 0.0183 Jul 2007

*Concentrations >1 μg/L are bolded.

6.2.2.2. Ground Water Monitoring Data

Criteria Data

Number of Ground Water Detections 67 (6,316 Total Samples)

Lowest Ground Water Detection 0.0031 μg/L (Madison County, AL; Jan 2001)

Highest Ground Water Detection 2.6858 μg/L (Collier County, FL; April 2009)

Earliest Detection 0.42 μg/L (Edgecombe County, NC; August 1993)

Latest Detection 0.0639 μg/L (Madison County, AL; March 2012)
23

State County Detection 

Numbers

Concentration

(μg/L)

Collection Date

Range

AL

Autauga, Colbert, Elmore, Lawrence, 

Limestone, Madison, Montgomery, 

Tuscaloosa

36 0.0031 - 0.0853 Jun 1999 – Mar 

2012

CO Weld 1 0.43 Mar 1994

CT Hartford 1 0.007 Aug 1993

FL Collier, Hendry 5 0.0559 - 2.6858 Apr – Jun 2009

GA Miller, Sumter, Tift, Turner, Worth 10 0.0045 - 0.83 Sep 93 – Sep 03

ID Minidoka 4 0.008 - 0.26 Jun 93 – Jul 05

NJ Ocean 1 0.23 Sep 1998

NY Suffolk 1 0.1189 Jul 2007

NC Edgecombe, Greene, Lenoir 4 0.0367 - 0.42 Aug 93 – Apr 02

SC Hampton, Lexington 2 0.1061 - 0.14 Jun 97 – Aug 07

TN Carroll, Madison 2 0.0032 - 0.018 Mar 2011

*Concentrations >1 μg/L are bolded.

6.2.3. Aldicarb Sulfone

6.2.3.1. Surface Water Monitoring Data

Criteria Data

Number of Surface Water Detections 12 (8,344 Total Samples)

Lowest Surface Water Detection 0.065 μg/L (Madison County, AL; October 2000)

Highest Surface Water Detection 0.1574 μg/L (Denver, CO; April 2002)

Earliest Detection 0.07 μg/L (Washoe County, NV; July 1994)

Latest Detection 0.0059 μg/L (Sarpy County, NE; August 2010)

State County Detection 

Numbers

Concentration

(μg/L)

Collection Date

Range

AL Madison 8 0.065 - 0.1035 Apr 2000 – Apr 2010

CO Denver 1 0.1574 Apr 2002

NE Sarpy 1 0.0059 Aug 2010

NV Washoe 1 0.07 Jul 1994

NY Suffolk 1 0.0287 Jul 2007

6.2.3.2. Ground Water Monitoring Data

Criteria Data

Number of Ground Water Detections 61 (6,331 Total Samples)

Lowest Ground Water Detection 0.035 μg/L (Hendry County, FL; May 2009)

Highest Ground Water Detection 0.9412 μg/L (Collier County, FL; June 2009)

Earliest Detection 0.32 μg/L (Edgecombe County, NC; August 1993)

Latest Detection 0.0844 μg/L (Limestone County, AL; March 2012)

State County Detection 

Numbers

Concentration

(μg/L)

Collection Date

Range
24

AL

Autauga, Colbert, Lawrence, 

Limestone, Madison, Montgomery, 

Tuscaloosa

38 0.089 - 0.1592 Jun 1999 – Mar 

2012

FL Collier, Hendry 5 0.0035 - 0.9412 Apr – Jun 2009

GA Miller, Sumter, Tift, Turner, Worth 8 0.085 - 0.0946 May 95 – Sep 03

ID Minidoka 1 0.0073 Jul 2005

NY Suffolk 1 0.1571 Jul 2007

NC Edgecombe, Greene 3 0.032 - 0.32 Aug 93 – Apr 02

SC Hampton, Lexington, Sumter 4 0.04 - 0.14 May 97 – Aug 07

TN Madison 1 0.0094 Mar 2011

6.2.4. USGS NAWQA Monitoring Data Summary

Monitoring data from USGS NAWQA was more extensive than that of USEPA 

STORET. Results shows that aldicarb was detected predominantly in surface water (54 samples), 

while sulfone and sulfoxide were mostly in the groundwater (61 & 67 samples). The bulk of the 

detection frequencies for parent aldicarb in surface water were in the Southeastern U.S., where 

out of 54 samples, 43 were in Georgia. Except for 2 samples were from the same sites, all of 

them were from different sampling sites. A few sites in Alabama, specifically Madison County 

were monitored for aldicarb, sulfone, and sulfoxide in groundwater for once a month from March 

2000 to March 2001. The detection frequencies for both aldicarb sulfone and sulfoxide were also 

in the Southeastern U.S.

USGS NAWQA database follows similar trend to that of USEPA STORET where it is 

non-targeted monitoring and the timing of monitoring is irregular. Further, the sample collection 

was not targeted for aldicarb use and the data cannot be correlated with use. 

6.3. California Department of Pesticide Regulation (CDPR) Surface Water Database

The CDPR Surface Water Database indicates that aldicarb TTR was analyzed at 293

surface water sites in California at various times from February 1991 to October 2010. A total of 

6795 samples were collected. While some sites were sampled for a total of 16 times over the span 

of 4 years, most of the sites were sampled at least 3 or more times at various times. Aldicarb and 

its residues were detected in a total of eleven samples, where eight were of parent aldicarb. The 

earliest detection of aldicarb was in San Joaquin River, Stanislaus in July 1991 and the most recent 

was in two storm drain samples in Sacramento on August 2009 with the lowest range concentration 

of 0.084-0.086 μg/L. Aldicarb was detected in the same sampling point twice (Miles Creek, 

Merced County) with the highest measured concentration of 5.4 μg/L on June 2007 but decreased 

10-fold to 0.53 in June 2008. Other detections of aldicarb occurred in Colusa Basin drain, Yolo 

(0.7 μg/L) on April 2000, Deadman Creek, Merced (1.2 μg/L) on June 2007, and Logan Creek, 

Colusa (1.5 μg/L) on May 2008. 

Aldicarb sulfone was detected in two samples, 0.05 μg/L on August 1991 in San Joaquin 

River and 0.258 μg/L on February 1992 in Turlock Irrigation District drain, both on Stanislaus

County. Meanwhile, sulfoxide was measured in one sample at 0.28 μg/L on July 1991 in San 

Joaquin River. 

6.4. Bayer CropScience Monitoring Studies
25

In 2006, Bayer CropScience, submitted five retrospective ground water monitoring studies 

to look for residues of aldicarb and its sulfoxide and sulfone metabolites in potable water from 

private wells in aldicarb use areas. This study monitored 1,673 drinking water wells and collected 

information on ground-water depth, well depth, casing depth, well type and age, soil types, recent 

aldicarb use history, crops, and distance of the well from the treated field. The study sampled 

drinking water wells in five regions of the country: the Southeastern US (800 wells), the 

Mississippi Delta (169 wells), the Pacific Northwest (303 wells), Texas (201 wells), and California 

(200 wells). The study found that aldicarb residues – predominantly the sulfoxide and sulfone 

metabolites – were detected in 10 percent of the wells sampled. The greatest frequencies of 

detections were in the Southeastern US (16%, with a maximum detect of 2.9 μg/L) and the 

Mississippi Delta (9%, with a maximum detect of 2.6 μg/L) regions. Because the single samples 

represent a snapshot in time, the Agency assumed that the measured concentrations reflected a 

median concentration for that particular well. Frequency and magnitudes of detection for aldicarb 

residues were generally greater for wells located within 300 feet of a field (~10% of wells had 

detections); aldicarb residues were detected in 4-6% of wells located >300 feet from the field, 

although detections were < 1 μg/L. A comparison of wells located near fields with restricted soils 

(as identified in the previously registered Temik 15G label) to those where the surrounding fields 

contained no restricted soils showed that, while the frequency of aldicarb detections was greater 

for wells near restricted soil types, the magnitude of aldicarb residues was greater for wells with 

no restricted soil types.

6.5. Monitoring Data Summary

Aldicarb, aldicarb sulfoxide, and aldicarb sulfone were monitored in non-targeted sites for 

surface and groundwater in all 50 states in the U.S. including the District of Columbia from 

February 1986 to December 2014. Note that much of this monitoring data was collected prior to 

mitigation and use reduction associated with reregistration of aldicarb. The mitigation was 

implemented in 2009. 

Concentrations of aldicarb detected in surface water were higher than that of groundwater 

and inversely, its sulfoxide and sulfone were higher in groundwater than surface water. The highest 

detections of aldicarb residues of concern in these databases are 5.4 μg/L in surface water (parent 

aldicarb) and 9.0 μg/L in ground water (sulfone). These concentrations are within an order of 

magnitude of modeled chronic exposure estimates (5.68 μg/L surface water and 21 μg/L ground 

water) for aldicarb residues of concern.

Overall, the 2009 mitigation implementation may have caused the decrease in the number 

of detections and concentrations of aldicarb, aldicarb sulfoxide, and aldicarb sulfone in surface 

water. However, since the monitoring databases were non-targeted, especially for aldicarb use, the 

observation cannot be verified by the lack of detections of aldicarb and its residues in surface water 

samples post 2009. Further, the monitoring results following mitigation has not indicated a clear 

trend of decline on aldicarb residues concentrations in groundwater. Aldicarb was still detected at 

0.64 μg/L on April 2012, aldicarb sulfoxide at 0.3 μg/L on May 2012, and aldicarb sulfone at 0.35 

μg/L on May 2012. Hence, the monitoring results further supports the submitted studies and 

published literatures that aldicarb residues are highly mobile in the soil profile and exhibit 

persistence in subsurface environment and groundwater. 

 
26

7. References

Food and Agriculture Organization of the United Nations (FAO). 2014. Assessing soil 

contamination A reference manual; Parameters of pesticides that influence processes in 

the soil. Agriculture and Consumer Protection Department. 

http://www.fao.org/docrep/003/x2570e/x2570e06.htm

Health Effects Division. 2005. Estimation Of Cumulative Risk From N-Methyl Carbamate 

Pesticides: Preliminary Assessment. United States Environmental Protection Agency 

EPA-HQ-OPP-2003-0360-0013.

U.S. Department of Agriculture (USDA). 2008. Crop Profiles. NSF Center for Integrated Pest 

Management (host). U.S. Department of Agriculture, Cooperative State Research, 

Education and Extension Service. Last updated: Sep. 4, 2008. Online at: 

http://www.ipmcenters.org/cropprofiles/CP_form.cfm

U.S. Environmental Protection Agency (USEPA). 2005. Golf Course Adjustment Factors for 

Simulated Aquatic Exposure Concentrations. Environmental Fate and Effects Division. 

Internal memorandum. Dec. 7, 2005.

USDA. 2008a. 2007 Census Publications, Ag Atlas Maps, Crops and Plants. U.S. Department 

of Agriculture, National Agricultural Statistics Service. Accessed on May. 08, 2015. 

Online at: 

http://www.agcensus.usda.gov/Publications/2002/Ag_Atlas_Maps/Crops_and_Plants/ind

ex.asp

USEPA. 2007. Reregistration Eligibility Decision for Aldicarb. U.S. Environmental Protection 

Agency. Office of Pesticide Programs, Aldicarb Reregistration Eligibility Decision 

Team: Special Review and Reregistration Division, Health Effects Division, 

Environmental Fate and Effects Division, Biological and Economic Analysis Division, & 

Registration Division. September, 2007.

USEPA. 2009. Guidance for Selecting Input Parameters in Modeling the Environmental Fate 

and Transport of Pesticides. Version 2.1. U.S. Environmental Protection Agency, Office 

of Pesticide Programs, Environmental Fate and Effects Division, Oct. 22, 2009. 

http://www.epa.gov/oppefed1/models/water/input_parameter_guidance.htm

USEPA. 2012. NAFTA Guidance for Evaluating and Calculating Degradation Kinetics in 

Environmental Media. Office of Chemical Safety and Pollution Prevention, 

Environmental Fate and Effects Division. Internal guidance memorandum. Dec. 17, 

2012.

USEPA. 2012a. Identification and Evaluation of Existing Models for Estimating Environmental 

Pesticide Transport to Groundwater. Final Report (Draft). U.S. Environmental Protection 

Agency; Health Canada. Jan. 27, 2012.
27

USEPA. 2012b. Guidance for Selecting Input Parameters for Modeling Pesticide Concentrations 

in Groundwater Using the Pesticide Root Zone Model. Version 1.0. U.S. Environmental 

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

Division; Health Canada, Pesticide Management Regulatory Agency, Environmental 

Assessment Directorate. Oct. 15, 2012.

USEPA. 2012c. Guidance on Development and Use of Percent Cropped Area and Percent Turf 

Area Adjustment Factors in Drinking Water Exposure Assessments: 2012 Update. 

Internal Environmental Fate and Effects Division memorandum. U.S. Environmental 

Protection Agency, Office of Chemical Safety and Pollution Prevention. Mar. 16, 2012.

USEPA. 2012d. Approval of PRZM-GW for Use in Drinking Water Exposure Assessments. 

Internal Environmental Fate and Effects Division memorandum. U.S. Environmental 

Protection Agency, Office of Chemical Safety and Pollution Prevention. Dec. 11, 2012. 

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

USEPA. 2014. Dodd, N. and W. Phang. Abamectin: Recommendation for the Residue of 

Concern in Drinking Water. DP barcode 420073. Memorandum from the Health Effects 

Division to the Environmental Fate and Effects Division. Apr. 25, 2014.

USEPA. 2014a. Water Models. U.S. Environmental Protection Agency, Pesticides, Science and 

Policy, Models and Databases. Last updated Jul. 9, 2013. 

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

USEPA. Ruhman, M., Hetrick, J., Jones, R. Guidance for Modeling Pesticide Total Toxic 

Residues. (Draft Document)

USEPA. 2014. Brady, D. Guidance on Development and Use of Community Water System 

Drinking Water Intake Percent Cropped Area Adjustment Factors for Use in Drinking

Water Exposure Assessments: 2014 Updated, September 12, 2014.

United States Geological Survey (USGS). 2015. National Water-Quality Assessment (NAWQA) 

Program, Pesticide National Synthesis Project, Pesticide Use Maps – Aldicarb. 

http://water.usgs.gov/nawqa/pnsp/usage/maps/show_map.php?year=2011&map=ALDIC

ARB&hilo=L&disp=Aldicarb (accessed June. 3, 2015)

Health Effects Division. 2005. Estimation Of Cumulative Risk From N-Methyl Carbamate 

Pesticides: Preliminary Assessment. United States Environmental Protection Agency EPA-HQOPP-2003-0360-0013.

Office of Pesticide Programs. 2007. Revised N-Methyl Carbamate Cumulative Assessment.

United States Environmental Protection Agency. 

http://www.epa.gov/oppsrrd1/REDs/nmc_revised_cra.pdf

Dutta, Subijoy. 1999. Drinking Water Memorandum for Aldicarb for the Reregistration

Eligibility Decision Document (RED). Internal EPA Memorandum to Robert McNally dated 

April 4, 1999.
28

D247759. Dutta, Subijoy. 1999. Updated Drinking Water Assessment for Aldicarb (Temik®

15G). Internal EPA Memorandum dated September 21, 1999. Same as D254590.

D246901. Environmental Fate and Effects Division. EFED Chapter for the Reregistration 

Eligibility Document for Aldicarb. Dated May 15, 2001.

D316754. Angier, Jonathan. 2005. Tier 2 Drinking Water Assessment for Aldicarb and its Major 

Degradates Aldicarb Sulfoxide and Aldicarb Sulfone. Internal EPA Memorandum to Robert 

McNally dated April 4, 2005.

D333309. Thurman, Nelson and Jonathan Angier. 2006. Drinking Water Exposure Assessment 

for Total Aldicarb Residues (Parent, Aldicarb Sulfoxide, and Aldicarb Sulfone) Based on the NMethyl Carbamate Cumulative Risk Assessment. Internal EPA Memorandum to Sherri Kinard 

and Felicia Fort dated October 23, 2006.

D299881. Shanaman, Lucy. Refinement to Tier 2 Drinking Water Assessment Tobacco Uses of 

Aldicarb and its Major Degradates Aldicarb Sulfoxide and Aldicarb Sulfone. Internal EPA 

Memorandum to Christine Olinger dated April 10, 2009.

D348436. Thurman, Nelson and Jonathan Angier. 2008. Drinking Water Exposure Assessment 

for Proposed Expansion of Aldicarb Use on Potatoes Into 6 Additional States (CO, MI, MN, ND, 

SD, WY). Internal EPA Memorandum to John Hebert and Christine Olinger dated August 26, 

2008.

7.1. Submitted Environmental Fate and Product Chemistry Studies

MRID Citation Reference

131083 Maynard, M.; Ku, C.; Gruber, V.; et al. (1982) Hydrolysis of Avermectin B1a (MK-0936). 

(Unpublished study received Jan 3, 1983 under 618-EX-10; submitted by Merck & Co., Inc., 

Rahway, NJ; CDL:249152-F)

159163 MSD Agvet Inc. (1983) Residue and Environmental Data: [MK-936]. Unpublished compilation. 

160 p.

41191501 Wehner, T. (1989) Additional Soil Residue Data in Support of Applications for Registration of 

Abamectin Soil Leaching and Dissipation Study: Project ID: Merck No. 001-87-6045R; ADC No. 

992. Unpublished study prepared by Merck Sharp & Dohme Research Laboratories and Analytical 

Development Corp. 18 p. 

42627601 Wertz, P. (1993) Soil Residue Data in Support of an Application for Registrations of Abamectin: 

Soil Leaching and Dissipation Study 001-87-6045R: A Supplement: Lab Project Number: 618-936-

6045. Unpublished study prepared by Analytical Development Corp. 603 p. 

46877502 Friis, M. (2006) Product Chemistry - Abamectin Technical (CHA 204) - EPA Reg. No. 4787 -

(none yet) Group B - Physical /Chemical Properties. Project Number: 

MVF/060500/ABA/204/B/USA, PYC/170, PYC/171. Unpublished study prepared by Cheminova 

Agro A/S. 399 p.
29

MRID Citation Reference

47436204 Wagner, J. (2008) Abamectin Technical Herbicide: Stability to Normal and Elevated 

Temperatures, Metals, and Metal Ions: Oxidation/Reduction: Flammability: Explodability: Storage 

Stability: Miscibility: Corrosion Characteristics: Dielectric Breakdown Voltage: Viscosity: Boiling 

Point: Dissociation Constants in Water: Particle Size, Fiber Length, and Diameter Distribution: 

Partition Coefficient: Water Solubility: Vapor Pressure. Unpublished study prepared by Wagner 

Regulatory Associates, Inc. 6 p.

49071001 Phaff, R. (2001) NOA422601 - Soil Photolysis of [23-(Carbon 14] - Labelled NOA422601 

(Avermectin B1a) - Under Laboratory Conditions: Final Report. Project Number: 

TK0176242/OCR, 00RP04. Unpublished study prepared by Syngenta Crop Protection, AG. 85p.

49071002 Morgenroth, U. (2001) NOA422601 - Adsorption/Desorption of [23-(Carbon14)]-NOA422601 

(Avermectin B1a) in Various Soils: Final Report. Project Number: TK0176241/OCR, 99MO05. 

Unpublished study prepared by Syngenta Crop Protection, AG. 83p.

49071004 Buckel, T. (2002) NOA422601: Metabolism and Rate of Degradation of [23-(Carbon 14)] -

Labelled NOA422601 (Avermetin B1a) Under Aerobic and Anaerobic Laboratory Conditions in 

Aquatic Systems: Final Report. Project Number: TK0176250/OCR, 01TB01. Unpublished study 

prepared by Syngenta Crop Protection, AG. 181p.

49071005 Adam, D. (2001) Aqueous Photolysis of [23-(Carob 14)] - Labelled NOA422601 (Avermectin 

B1A) Under Laboratory Conditions (Including Amendment No. 1 to Report on Study 01DA01): 

Final Report. Project Number: TK0176249/OCR, 01DA01. Unpublished study prepared by 

Syngenta Crop Protection, AG. 104p.

49071006 Adam, D. (2001) NOA422601: Rate of Degradation of [23-(Carbon 14)] - Labelled NOA422601 

(Avermectin B1A) in One Soil Under Various Laboratory Conditions at 10 (Degrees Celsius), 20 

(Degrees Celsius) and 30 (Degrees Celsius): Final Report. Project Number: TK0176246/OCR, 

00DA07. Unpublished study prepared by Syngenta Crop Protection, AG. 92p.

49071007 Nicollier, G. (2001) NOA422601: Metabolism and Rate of Degradation of [23-(Carbon 14)] -

Labelled NOA422601 (Avermetin B1a) Under Aerobic and Anaerobic Laboratory Conditions in

One Soil at 20 (Degrees Celsius): Final Report. Project Number: TK0176252/OCR, 99AG07. 

Unpublished study prepared by Syngenta Crop Protection, AG. 158p.

49071013 Jacobson, B.; Hampton, R.; Perez, R.; et al. (2013) Abamectin - Dissipation of Abamectin SC 

(020) Applied to Turf in New York: Final Report. Project Number: TK0047099/OCR, 796/43, 

903/TK0047099. Unpublished study prepared by Waterborne Environmental, Inc. (WEI), Syngenta 

Crop Protection, LLC and ADPEN Laboratories, Inc. 702p.

49071014 Jacobson, B.; Hampton, R.; Perez, R.; et al. (2013) Abamectin - Dissipation of Abamectin SC 

(020) Applied to Turf in Georgia: Final Report. Project Number: TK0047101/OCR, 796/44, 

903/TK0047101. Unpublished study prepared by Waterborne Environmental, Inc. (WEI), ADPEN 

Laboratories, Inc. and Syngenta Crop Protection, LLC. 704p.

49071015 Jacobson, B.; Hampton, R.; Perez, R.; et al. (2013) Abamectin - Dissipation of Abamectin SC 

(020) Applied to Turf in the Central Valley of California: Final Report. Project Number: 

TK0047103/OCR, 796/42, 903/TK0047103. Unpublished study prepared by Waterborne 

Environmental, Inc. (WEI), Syngenta Crop Protection, LLC and ADPEN Laboratories, Inc. 710p.

49178901 Zbaeren, A.; Nicollier, G. (2012) Rate of Degradation of [23-(Carbon 14)] - Labelled NOA422601 

(Avermectin B1a) - in Various Soils under Aerobic Laboratory Conditions at 20 Degrees Celsius 

(Including Amendment No. 1 to Final Report 01RP02): Final Report. Project Number: TK0176243 

01RP02. Unpublished study prepared by Syngenta Crop Protection, AG. 104p.
30

Appendix A. Model Output Files

SWCC Output Files.zip PRZMGW FL Central Ridge.zip
31

Appendix B. Regional PCA Refinement

Standard percent cropped areas (PCA) are used as conservative default estimates of the 

extent of watershed on which agricultural crops of unknown specific PCA are grown (USEPA, 

2012c). The exposure estimates from PRZM/EXAMS were multiplied by regional PCA factors 

for HUC-2 watershed basins of the U.S. in order to account for the highest extent of watershed in 

the regions on which agricultural crops are grown (Effland et al., 1999). Figure B1 displays the 

18 HUC-2 watershed basins of the contiguous U.S. for which regional PCA factors are 

calculated.

Figure B1. The Eighteen HUC-2 Watershed Basins of the Contiguous United States.

The first step in this process was to use 2002 AgCensus data (i.e, dot-density maps) to 

ascertain the states in which the modeled crops are grown at a density sufficient to be mapped 

(USDA, 2008a). These data and the geographic limitations imposed by the labels were used to 

tabulate states per PCA region where aldicarb might be applied to the modeled uses (Table B1). 

The second step was to assign a PRZM/EXAMS scenario for modeling each use-PCA region 

combination where aldicarb might be applied (Table B3). The strategy for assigning surrogate 

scenarios was to attempt to use current scenarios to represent areas of similar meteorological and 

agronomic conditions. For uses where there are limited numbers of currently approved 

scenarios, current scenarios representing areas west of the Rockies were used to represent large 

regions west of the Rockies that were generally to the south and/or east of the scenario location. 

Similarly, current scenarios representing areas east of the Rockies were used to represent large 
32

regions east of the Rockies that were generally to the south and/or west of the scenario location. 

However, scenarios representing areas of South Texas or Florida were used to represent the 

HUC-2 watershed basin in which they are located as well as watershed basins further north 

where alternative scenarios were less representative.

Following the assignment of model scenarios to each use-PCA region combination, the 

modeling was conducted and the regional PCA-adjusted 1-in-10-year peak, 1-in-10-year annual 

average, and 30-year average EDWCs were tabulated for each combination of use and PCA 

region (Table B7), as discussed in the following sections.

Table B1. Aldicarb Labeled Use Summary Table

HUC-2 Basin Name Soybeans Cotton

Other Row Crops 

(tobacco, sugarbeets, 

peanut)

Vegetables and 

Ground Fruit

East of Eastern Divide

1 New England

2 Mid Atlantic Soybean Cotton Peanuts

3 South Atlantic Soybean Cotton Peanuts

Mid-Continent (Mississippi River Basin)

4 Great Lakes Dry Beans

5 Ohio Soybean Cotton

6 Tennessee Soybean Cotton

7 Upper 

Mississippi Cotton

8 Lower 

Mississippi Cotton Peanuts

9 Souris

10 Missouri Cotton Sugarbeets Dry Beans

11 Arkansas Cotton Sugarbeets, Peanuts Dry Beans

12 Texas Gulf Cotton Peanuts

13 Rio Grande Cotton Sugarbeets, Peanuts Dry Beans

West of Western Divide

14 Upper Colorado Cotton Sugarbeets Dry Beans

15 Lower Colorado Cotton

16 Great Basin Cotton Sugarbeets

17 Pacific 

Northwest Cotton Sugarbeets Dry Beans

18 California Cotton Sugarbeets Dry Beans
33

Table B2. DWI PCA Calculations

HUC-2 Soybeans Cotton Other Row Crops (tobacco, 

sugarbeets, peanut)

Vegetables and 

Ground Fruit DWI PCA

1

2 0.11 0.06 *0.82 0.82

3 0.2 0.08 *0.52 0.52

4 0.04 0.04

5 0.59 0.02 0.59

6 0.1 0.04 0.1

7 0 0

8 *0.75 0.75

9

10 0 *1.0 0.02 1

11 0.07 *0.79 0.01 0.79

12 0.21 *0.77 0.77

13 0.01 *0.52 0.01 0.52

14 0 *0.37 0.01 0.37

15 0.04 0.04

16 0 *0.04 0.04

17 0 *0.72 0.01 0.72

18 0.05 *0.74 0.16 0.74

*Default All-Ag PCA (no individual DWI PCA available)
34

Table B3. PRZM Scenario Identification to each combination of use and HUC-2 region.

HUC-2 Soybeans Cotton

Other Row Crops 

(tobacco, sugarbeets, 

peanut)

Vegetables and 

Ground Fruit

1

2 1PA Corn NC Cotton NC Peanuts

3 MS Soybean NC Cotton, 2

MS Cotton NC Peanuts

4 MI Beans

5

1,5IL Corn, IN Corn, 

OH Corn, PA Corn NC Cotton

6 MS Soybean NC Cotton, 2

MS Cotton

7 MS Cotton

8 MS Cotton NC Peanuts

9

10 MS Cotton MN Sugar beets MI Beans

11 MS Cotton ID Potato, 4NC Peanuts MI Beans

12 MS Cotton NC Peanuts

13 CA Cotton ID Potato, 4NC Peanuts OR Sn Beans

14 CA Cotton 3ID Potato OR Sn Beans

15 CA Cotton

16 CA Cotton 3ID Potato

17 CA Cotton 3ID Potato OR Sn Beans

18 CA Cotton 3ID Potato OR Sn Beans

* Bold indicate the scenario was selected. 1 Soybean is rotated with corn in the same field, thus corn scenarios are selected as surrogates for soybeans in their respective 

HUC 2 region.

2 MS Cotton is selected over NC Cotton when both share the same HUC2 because MS Cotton provides a more conservative 

estimate.

3 Potato scenario were chosen as surrogate in absence of appropriate representation of the HUC region. Potato is a root crop 

which is deemed similar to that of sugar beets.

4 NC Peanuts were chosen over ID Potato when both overlapped because the model yielded higher output. 5 IL Corn was selected because it yielded the highest estimates.
35

Table B4. Adjusted EDWCs (μg/L) Peak by use and by regional DWI PCA specific to each HUC-2 region

HUC2 Soybeans Cotton

Other Row 

Crops (tobacco, 

sugarbeets, 

peanut)

Vegetables 

and Ground 

Fruit

MAX 

EDWCS 

Peak

DWI 

PCA

Adjusted 

EDWCS Peak

1

2 29.5 51.1 50.4 51.1 0.82 41.90

3 26.7 84.1 50.4 84.1 0.52 43.73

4 73.1 73.1 0.04 2.92

5 80.6 51.1 80.6 0.59 47.55

6 26.7 84.1 84.1 0.1 8.41

7 84.1 84.1 0 0.00

8 84.1 50.4 84.1 0.75 63.08

9

10 51.1 187 73.1 187 1 187.00

11 84.1 50.4 73.1 84.1 0.79 66.44

12 84.1 50.4 84.1 0.77 64.76

13 23.1 50.4 70.3 70.3 0.52 36.56

14 23.1 11.5 70.3 70.3 0.37 26.01

15 23.1 23.1 0.04 0.92

16 23.1 11.5 23.1 0.04 0.92

17 23.1 11.5 70.3 70.3 0.72 50.62

18 23.1 11.5 70.3 70.3 0.74 52.02

Table B5. Adjusted EDWCs (μg/L) Annual Average by use and by regional DWI PCA specific to each 

HUC-2 region

HUC2 Soybeans Cotton

Other Row 

Crops (tobacco, 

sugarbeets, 

peanut)

Vegetables 

and Ground 

Fruit

MAX 

EDWCS 

Annual 

AVG

DWI 

PCA

Adjusted 

EDWCs

Annual AVG

1

2 2.92 3.65 4.01 4.01 0.82 3.29

3 1.96 5.64 4.01 5.64 0.52 2.93

4 7.35 7.35 0.04 0.29

5 7.8 3.65 7.8 0.59 4.60

6 1.96 5.64 5.64 0.1 0.56

7 5.64 5.64 0 0.00

8 5.64 4.01 5.64 0.75 4.23

9

10 1.75 16 7.35 16 1 16.00

11 5.64 4.01 7.35 7.35 0.79 5.81

12 5.64 4.01 5.64 0.77 4.34

13 1.75 4.01 6.52 6.52 0.52 3.39

14 1.75 1.3 6.52 6.52 0.37 2.41

15 1.75 1.75 0.04 0.07

16 1.75 1.3 1.75 0.04 0.07

17 1.75 1.3 6.52 6.52 0.72 4.69

18 1.75 1.3 6.52 6.52 0.74 4.82
36

Table B6. Adjusted EDWCs (μg/L) 30-Year Average by use and by regional DWI PCA specific to each 

HUC-2 region

HUC2 Soybeans Cotton

Other Row 

Crops (tobacco, 

sugarbeets, 

peanut)

Vegetables 

and Ground 

Fruit

MAX 

EDWCS 30-

Yr AVG

DWI 

PCA

Adjusted 

EDWCs 30-

Yr AVG

1

2 0.89 1.71 1.29 1.71 0.82 1.40

3 0.578 2.18 1.29 2.18 0.52 1.13

4 2.68 2.68 0.04 0.11

5 2.21 1.71 2.21 0.59 1.30

6 0.578 2.18 2.18 0.1 0.22

7 2.18 2.18 0 0.00

8 2.18 1.29 2.18 0.75 1.64

9

10 0.45 5.3 2.68 5.3 1 5.30

11 2.18 1.29 2.68 2.68 0.79 2.12

12 2.18 1.29 2.18 0.77 1.68

13 0.45 1.29 1.83 1.83 0.52 0.95

14 0.45 0.29 1.83 1.83 0.37 0.68

15 0.45 0.45 0.04 0.02

16 0.45 0.29 0.45 0.04 0.02

17 0.45 0.29 1.83 1.83 0.72 1.32

18 0.45 0.29 1.83 1.83 0.74 1.35

Table B7. Regional PCA Adjusted EDWCs Summary (μg/L)

HUC-2 PCA USED 1-in-10 Year Peak 1-in-10 year Annual Average 30 year Average

1 0.00 0.00 0.00 0.00

2 0.82 41.90 3.29 1.40

3 0.52 43.73 2.93 1.13

4 0.04 2.92 0.29 0.11

5 0.59 47.55 4.60 1.30

6 0.1 8.41 0.56 0.22

7 0 0.00 0.00 0.00

8 0.75 63.08 4.23 1.64

9 0.00 0.00 0.00 0.00

10 1 187.00 16.00 5.30

11 0.79 66.44 5.81 2.12

12 0.77 64.76 4.34 1.68

13 0.52 36.56 3.39 0.95

14 0.37 26.01 2.41 0.68

15 0.04 0.92 0.07 0.02

16 0.04 0.92 0.07 0.02

17 0.72 50.62 4.69 1.32

18 0.74 52.02 4.82 1.35
37

Appendix C. List of Vulnerable Soils and Soil Restrictions on Meymik 15G Label

Adobe Acrobat 

Document
c c

MEYMIK 15G EPA Reg. No. 87895-

RESTRICTED USE PESTICIDE

DUE TO ACUTE ORAL TOXICITY and TO GROUND WATER CONTAMINATION

For retail sale to and use only by Certified Applicators or persons under the direct supervision of a Certified Applicator, and only

for those uses covered by the Certified Applicator's Certification.

MEYMIK 15G

EPA Reg. No. 87895-

Environmental Precautions and Soil Type Restriction Tables

Refer to the container label for additional use precautions and directions.

Ag Logic LLC

121 S. Estes Drive, Suite 101

Chapel Hill, NC 27514

ENVIRONMENTAL PRECAUTIONS

GENERAL USE RESTRICTIONS

AGRICULTURAL CHEMICALS HAVE THE POTENTIAL TO MOVE INTO SHALLOW GROUND WATER.

THE FOLLOWING RESTRICTIONS HAVE BEEN DEVELOPED TO PROTECT DRINKING WATER SUPPLIES.

DO NOT APPLY WITHIN 50 FEET OF ANY DRINKING WATER WELL TO MINIMIZE CONTAMINATION BY SURFACE RUNOFF.

MORE STRINGENT RESTRICTIONS MAY BE REQUIRED, AS DISCUSSED BELOW.

Do not wash, load, or empty application equipment near any well, as this practice is a potential source of ground water contamination.

In fields having soils with less than 15% field moisture holding capacity, special care must be taken not to over-irrigate, since substantial

over-irrigation promotes the leaching of chemicals.

Contact your state pesticide regulatory authority for further information on state requirements for the use of this product.

Some states have or may be developing more restrictive regulations regarding the use and application of MEYMIK 15G. Follow all state

regulations restricting the use and application of this product, including limitations on applications near drinking water sources. In all

cases, the more restrictive requirements must be followed. It is the responsibility of the applicator to document the construction of wells

claimed not to be shallow.

STATE SPECIFIC GROUND WATER LIMITATIONS

Do not apply this product in the states of Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York,

Pennsylvania, Rhode Island, Vermont or Wisconsin, or in Del Norte or Humbolt counties in California or in Curry County,

Oregon.

FOLLOW THE LISTED "ADDITIONAL RESTRICTIONS" if the following conditions are present:

18
i

MEYMIK15G EPA Reg. No. 87895-

STATE

SOILS FOR WHICH

RESTRICTIONS APPLY ADDITIONAL RESTRICTIONS

CO, DE, KS, KY, LA,

MD, MO, MS, NC,

TN, VA, WV

Loamy sand or sand surface soils

and subsoils with an average

organic matter in the upper 12

inches of less than 2% by weight.

See SOIL TYPE RESTRICTION

TABLES for specific soil types.

If a vulnerable soil is present and the water table is less than 25 feet below

ground surface, do not apply within 300 feet of a drinking water well unless it is

known or reasonably believed based upon authoritative sources that such wells

are either cased to 100 feet below ground level or a minimum of 30 feet below

the water table. If it is not known whether the water table is greater than 25

feet below ground surface, assume that the water table is less than 25 feet

below ground surface.

IA, IL, IN, Ml. MN.

MT, ND, NE, OH,

SD, WY

Sandy loam, loamy sand, or sand

surface soils, and loamy sand or

sand subsoils, with an average

organic matter in the upper 12

inches of less than 2% by weight.

See SOIL TYPE RESTRICTION

TABLES for specific soil types.

If a vulnerable soil is present and the water table is less than 25 feet below

ground surface, do not apply within 500 feet of a drinking water well unless it is

known or reasonably believed based upon authoritative sources that such wells

are either cased to 100 feet below ground level or a minimum of 30 feet below

the water table. If it is not known whether the water table is greater than 25

feet below ground surface, assume that the water table is less than 25 feet

below ground surface.

AL, GA, SC Vulnerable Cotton and Peanut Soils

in AL, GA and SC and Vulnerable

Soybean Soils in GA and SC.

Loamy sand or sand surface soils

and subsoils with an average

organic matter in the upper 12

inches of less than 2% by weight

See SOIL TYPE RESTRICTION

TABLES for specific soil types.

At planting application only to cotton, peanuts or soybeans

If MEYMIK 15G is applied to cotton, peanuts or soybeans as an At-plant

application and a vulnerable soil is present and the water table is less than 25

feet below ground surface, do not apply within 700 feet of a drinking water well

unless it is known or reasonably believed based upon authoritative sources that

such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater

than 25 feet below ground surface, assume that the water table is less than 25

feet below ground surface.

Side Dress Application Only or Split Application to cotton

If MEYMIK 15G is applied to cotton as a Side Dress application only and a

vulnerable soil is present and the water table is less than 25 feet below ground

surface, do not apply within 700 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are

either cased to 100 feet below ground level or a minimum of 30 feet below the

water table. If it is not known whether the water table is greater than 25 feet

below ground surface, assume that the water table is less than 25 feet below

ground surface.

If MEYMIK 15G is applied to cotton as an At-Plant application and a Side Dress

application and a vulnerable soil is present and the water table is less than 25

feet below ground surface, do not apply within 1000 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources

that such wells are either cased to 100 feet below ground level or a minimum of

30 feet below the water table. If it is not known whether the water table is

greater than 25 feet below ground surface, assume that the water table is less

than 25 feet below ground surface.

At-Planting and/or Post emergence application to peanuts

If MEYMIK 15G is applied to peanut as an At-Plant application and/or a Post

emergence (Pegging) application and a vulnerable soil is present and the water

table is less than 25 feet below ground surface, do not apply within 1100 feet of

a drinking water well unless it is known or reasonably believed based upon

authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether

the water table is greater than 25 feet below ground surface, assume that the

water table is less than 25 feet below ground surface. Do not make a post

emergence application to peanuts in South Carolina.

FL Vulnerable Peanut and Cotton Soils

Loamy sand or sand surface soils

and subsoils with an average

organic matter in the upper 12

inches of less than 2% by weight.

Any soil classified with a soil

hydrologic group of C or D is not

considered a restricted soil

regardless of other properties.

At planting application only.

If MEYMIK 15G is applied At-planting to peanuts or cotton and a vulnerable soil

is present (see soils listed below) and the water table is less than 25 feet below

ground surface, do not apply within 700 feet of a drinking water well unless it is

known or reasonably believed based upon authoritative sources that such wells

are either cased to 100 feet below ground level or a minimum of 30 feet below

the water table.

Side Dress Application Only or Split Application to cotton

If MEYMIK 15G is applied to cotton as a Side Dress application only and a

vulnerable soil is present and the water table is less than 25 feet below ground

19
MEYMIK15G EPA Reg. No. 87895-

STATE

FL

SOILS FOR WHICH

RESTRICTIONS APPLY

Other Soils, All Crops

ADDITIONAL RESTRICTIONS

surface, do not apply within 700 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are

either cased to 100 feet below ground level or a minimum of 30 feet below the

water table. If it is not known whether the water table is greater than 25 feet

below ground surface, assume that the water table is less than 25 feet below

ground surface.

If MEYMIK 1 5G is applied to cotton as an At-Plant application and a Side Dress

application and a vulnerable soil is present and the water table is less than 25

feet below ground surface, do not apply within 1000 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources

that such wells are either cased to 100 feet below ground level or a minimum of

30 feet below the water table. If it is not known whether the water table is

greater than 25 feet below ground surface, assume that the water table is less

than 25 feet below ground surface.

At-Planting and/or Post emergence application to peanuts

If MEYMIK 15G is applied to peanut as an At-Plant application and/or a Post

emergence (Pegging) application and a vulnerable soil is present and the water

table is less than 25 feet below ground surface, do not apply within 11 00 feet of

a drinking water well unless it is known or reasonably believed based upon

authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether

the water table is greater than 25 feet below ground surface, assume that the

water table is less than 25 feet below ground surface. Do not make a post

emergence application to peanuts in South Carolina.

Additional Information

In Florida, it is the responsibility of the applicator to document the construction

of wells claimed not to be shallow. This must consist of: (a) a copy of the well

completion report issued by the appropriate water management district; or (b) a

statement certified as to accuracy by a licensed well contractor. The U.S.D.A.

Natural Resources Conservation Service which serves your county can tell you

if the soils on your farm fall within the following types of vulnerable soils. If it is

not known whether the water table is greater than 25 feet below ground

surface, assume that the water table is less than 25 feet below ground surface.

See Section 5E-2, 028, Florida Administrative Code (F.A.C.), for additional

restrictions.

Adamsville Eglin Lake Penney

Alaga Florahome Lakeland Quartzipsamments

Alpin Fort Meade Neilhurst Satellite

Archbold Foxworth Orlando Tavares

Astatula Gainesville Orsino Valdosta

Bigbee Kershaw Ortega

Candler Klej Paola

State regulations require that MEYMIK 15G not be applied within 300 feet of

any drinking water well. See Section 5E-2, 028, F.A.C., and additional

restrictions for peanut and cotton above.

20
MEYMIK15G EPA Reg. No. 87895-

SOIL TYPE RESTRICTION TABLE

FOLLOW THE LISTED ADDITIONAL RESTRICTIONS IF THE SOIL TYPES ARE PRESENT IN YOUR STATE:

ALABAMA

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. At planting application only: if MEYMIK 15G is applied to cotton or peanuts as an

At-plant application and a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 700

feet of a drinking water well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to

100 feet below ground level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet

below ground surface, assume that the water table is less than 25 feet below ground surface. Side Dress Application Only: If MEYMIK

15G is applied to cotton as a Side Dress application only and a vulnerable soil is present and the water table is less than 25 feet below

ground surface, do not apply within 700 feet of a drinking water well unless it is known or reasonably believed based upon authoritative

sources that such wells are either cased to 100 feet below ground level or a minimum of 30 feet below the water table. If it is not known

whether the water table is greater than 25 feet below ground surface, assume that the water table is less than 25 feet below ground surface.

Split Application: If MEYMIK 15G is applied to cotton as an At-Plant application and a Side Dress application and a vulnerable soil is

present and the water table is less than 25 feet below ground surface, do not apply within 1000 feet of a drinking water well unless it is

known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a

minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume

that the water table is less than 25 feet below ground surface. At-Planting and/or Post emergence application to peanuts: If MEYMIK

15G is applied to peanut as an At-Plant application and/or a Post emergence (Pegging) application and a vulnerable soil is present and the

water table is less than 25 feet below ground surface, do not apply within 1100 feet of a drinking water well unless it is known or reasonably

believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30 feet below the

water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water table is less than

25 feet below ground surface.

alaga

alpin

americus

bassfield

bigbee

blanton

bruno

buncombe

chipley

chipola

corolla

crevasse

duckston

eustis

flomaton

foxworth

fripp

garcon

gorgas

jones

lakeland

latonia

leon

nugent

osier

pactolus

plummer

saffell

scranton

tarboro

COLORADO

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

bangston

bankard

barcus

baroid

batterson

bijou

blakeland

boel

brad

breece

bresser

canlodore

cascajo

chappell

chaseville

clarK fork

columbine

comad

corlena

corlett

costilla

cotopaxi

coyet

crestman

crustown

dailey

dix

dunday

dunul

dwyer

eachuston

ecklund

eghelm

ellicott

els

elsmere

falcon

farb

farisita

gilcrest

gracot

gretdivid

grieves

grimm

grimstone

gunbarrel

hiwan

inavale

ipage

ironsprings

juget

julesburg

kandaly

kassler

kerber

kettle

kippen

laird

laney

las animas

layoint

legault

lincoln

littlebear

lonetree

luning

mathis

maybell

medano

mespun

mido

mirror lake

moenkopie

moosed

mosca

munjor

mysten

nakai

nesda

newcomb

osgood

ouray

pando

patna

peetz

pescar

pineguest

platte

redcreek

resort

roswell

ruedloff

ruhe

ryark

san Isabel

sawcreek

schamber

schooner

sheppard

siebert

southace

space city

sphinx

spool

stapleton

stecum

tassel

thoroughfare

tipper

tipperary

tivoli

tomah

tomichi

trail

tricera

tullock

valent

valentine

wigton

willwood

yetull

zeona

DELAWARE

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

downer

evesboro

fort mott

galestown

hammonton

hooksan

hurlock

kenansville

klej

osier

plummer

pocomoke

rumford

21
MEYMIK15G EPA Reg. No. 87895-

SOILTYPE RESTRICTION TABLE (continued)

GEORGIA

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. At planting application only: if MEYMIK 15G is applied to cotton, peanuts or

soybeans as an At-plant application and a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not

apply within 700 feet of a drinking water well unless it is known or reasonably believed based upon authoritative sources that such wells are

either cased to 100 feet below ground level or a minimum of 30 feet below the water table. If it is not known whether the water table is

greater than 25 feet below ground surface, assume that the water table is less than 25 feet below ground surface. Side Dress Application

Only: If MEYMIK 15G is applied to cotton as a Side Dress application only and a vulnerable soil is present and the water table is less than

25 feet below ground surface, do not apply within 700 feet of a drinking water well unless it is known or reasonably believed based upon

authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30 feet below the water table. If it is

not known whether the water table is greater than 25 feet below ground surface, assume that the water table is less than 25 feet below

ground surface. Split Application: If MEYMIK 15G is applied to cotton as an At-Plant application and a Side Dress application and a

vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 1000 feet of a drinking water well

unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level

or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface. At-Planting and/or Post emergence application to peanuts: If

MEYMIK 15G is applied to peanut as an At-Plant application and/or a Post emergence (Pegging) application and a vulnerable soil is present

and the water table is less than 25 feet below ground surface; do not apply within 1100 feet of a drinking water well unless it is known or

reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

americus

bigbee

blanton

boulogne

buncombe

cainhoy

centenary

chipley

chipola

duckston

echaw

eustis

flomaton

foxworth

fripp

gorgas

hurricane

Johns

kershaw

kingsferry

kureb

lakeland

leon

lynn haven

mandarin

meadowbrook

molena

osier

ousley

penney

plummer

pottsburg

ridgeland

ridgewood

sapelo

scranton

valdosta

wateree

ILLINOIS

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within

or reasonably believed based upon authoritative sources that such wells are either cased

feet below the water table. If it is not known whether the water table is greater than 25

table is less than 25 feet below ground surface.

500 feet of a drinking water well unless it is known

to 100 feet below ground level or a minimum of 30

feet below ground surface, assume that the water

algansee

alviri

beavercreek

billet

bloomfield

boone

boyer

brems

burkhardt

carmi

carr

casco

Chelsea

chute

coloma

dickinson

disco

el dara

eleva

flagler

grable

granby

hodge

homer

hononegah

hoopeston

lamont

landes

lanier

lorenzo

matherton

minneiska

morocco

oakville

oshtemo

plainbo

plainfield

princeton

roby

rodman

saffell

sarpy

seafield

sparta

spinks

stonelick

thetford

watseka

zumbro

INDIANA

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within

or reasonably believed based upon authoritative sources that such wells are either cased

feet below the water table. If it is not known whether the water table is greater than 25

table is less than 25 feet below ground surface.

500 feet of a drinking water well unless it is known

to 100 feet below ground level or a minimum of 30

feet below ground surface, assume that the water

abscola

algansee

alvin

billet

bloomfield

bobtown

boyer

brady

branch

brems

bronson

bruno

carmi

casco

chatterton

Chelsea

coloma

conotton

conrad

desker

dickinson

elston

granby

gravelton

hanna

homer

hononegah

hoopeston

junius

kosciusko

landes

leoni

maumee

morocco

moundhaven

nesius

newton

oakville

ormas

oshtemo

ouiatenon

plainfield

princeton

prochaska

riverdale

roby

rodman

saugatuck

seafield

shipshe

sisson

sparta

spinks

stockland

stonelick

ted row

thetford

tyner

wasepi

watseka

zaborosky

zadog

22
C

MEYMIK15G EPA Reg. No. 87895-

SOIL TYPE RESTRICTION TABLE (continued)

IOWA

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within 500 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

backbone

billet

boone

brady

buckney

burkhardt

carr

chelsea

chute

dickinson

dickman

elrick

estherville

finchford

flagler

fruitfield

granby

hawick

hoopeston

klum

lament

lands

lilah

montieth

oesterle

perks

salida

sarpy

sparta

toolesboro

watseka

zenor

KANSAS

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

aline

bankard

dillwyn

dix

dwyer

els

elsmere

goltry

goodnight

gracemore

haxtun

inavale

kanza

las animas

likes

lincoln

pratt

sarpy

schamber

Simeon

thurman

tivoli

valent

valentine

KENTUCKY

If a vulnerable soil is present and the-water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

bruno

crevasse .

flomaton

iuka

lakin

molena

potomac

saffell

smithdale

LOUISIANA

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

alaga

bassfield

betis

bienville

bigbee

bruno

cheniere

crevasse

darden

eustis

felicity

flo

hackberry

haggerty

hainesville

kenney

lakeland

latonia

lotus .

nugent

osier

palm beach

peveto

MARYLAND

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

aura

carteret

colts neck

downer

dragston

duckston

evesboro

fisherman

fort mott

fripp

galestown

hammonton

hooksan

hurlock

ingleside

klej

lakeland

leetonia

leon

molena

newhan

osier

plummer

pocomoke

remlik

runclint

23
r r

MEYMIK15G EPA Reg. No. 87895-

SOIL TYPE RESTRICTION TABLE (continued)

MICHIGAN

If a vulnerable soil is present and the water table is less than 25, do not apply within 500 feet of a drinking water well unless it is known or

reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

abbaye

abscota

adams

alcona

algansee

allouez

alpena

alvin

arcadian

arkport

au gres

banat

battlefield

bixler

blue lake

bohemian

boyer

brady

branch

brems

bronson

channing

Chatham

Chelsea

chesaning

coloma

covert

croswell

cunard

deer park

deerton

desker

dickinson

dixboro

duel

dunbridge

east lake

eastport

eleva

elston

ensign

esau

evart

fabius

finch

freesoil

gilchrist

gladwin

granby

grattan

graycalm

grayling

guardlake

halfaday

hodenpyl

ingalls

ionia

ishpeming

kalkaska

karlin

kawbawgam

keweenaw

kingsville

kiva

klacking

koontz

kosciusko

landes

leelanau

leoni

liming

lode

mahtomedi

mancelona

manitowish

matherton

maumee

mecosta

menahga

millersburg

monico

montcalm

morocco

nadeau

newton

nottawa

oakville

oconto

ocqueoc

omega

onota

ormas

oshtemo

otisco

ottokee

paavola

padus

pelkie

pemene

pence

pequaming

perrin

peshekee

pipestone

plainfield

rapson

richter

ridgeville

riverdale

rodman

rousseau

rubicon

sarona

saugatuck

sayner

seafield

shawano

shelldrake

sisson

sparta

spinks

springlake

st. ignace

steuben

sturgeon

summerville

sundog

ted row

tekenink

thetford

trimountain

tyre

velvet

vilas

wainola

waiska

Wallace

wasepi

watseka

winterfield

zeba

Zimmerman

MINNESOTA

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within 500 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

abscota

alban

algansee

alvin

andrusia

anoka

arvilla

beavercreek

becker

bellchester

bergkeller

billet

boone

burkhardt

burnsville

carmi

caryville

Chelsea

chetek

claire

cloquet

conic

copaston

cormant

cowhorn

cromwell

deer park

dickinson

dickman

egeland

eleva

emmert

evart

faunce

finchford

flagler

fossum

friendship

gotham

granby

graycalm

hamar

hawick

hecia

hiwood

hoopeston

insula

kanaranzi

karlstad

kost

lamont

langola

lasa

leola

lilah

lino

lohnes

maddock

mahtomedi

marquette

meehan

menahga

mesaba

minneiska

nemadji

northfield

nymore

oesterle

omega

osakis

pierz

plainbo

plainfield

poppleton

quetico

red by

renshaw

rosholt

rosy

salida

sanburn

sartell

serden

shawano

sioux

soderville

sparta

spinks

sugarbush

torning

ulen

venlo

verndale

wamduska

watseka

waupaca

wawina

winterfield

zenor

Zimmerman

zippel

zumbro

MISSISSIPPI

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

alaga

bassfield

beulah

bigbee

bruno

crevasse

eustis

flomaton

lakeland

latonia

nugent

osier

pactolus

plummer

saffell

st. lucie

MISSOURI

If a vulnerable soil is oresent and the water table is less than 25 feet below around surface, do not aoolv within 300 feet of a drinking water

well unless.it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

alvin

beulah

bruno

canalou

carr

clana

crevasse

diehlstadt

eustis

finchford

hodge

landes

maiden

plainfield

sandbur

sarpy

scotco

shelldrake

sparta

wideman

24
MEYMIK15G EPA Reg. No. 87895-

SOIL TYPE RESTRICTION TABLE (continued)

MONTANA

If a vulnerable soil is present and the water table is less than 25, do not apply within 500 feet of a drinking water well unless it is known or

reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

alberton

ambrant

apeldorn

ashbon

ashuelot

assinniboine

bangston

bankard

banks

baxendale

bearmouth

beaverton

beenom

beisigl

belain

biglake

blackball

blanchard

bonner

brandenburg

branham

busby

cabba

calicott

castner

cheadle

Cheyenne

Chinook

dark fork

cohagen

colburn

comad

como

cowood

cozberg

dast

dayschool

dominie

dwyer

elkner

elmira

ervide

flasher

fleak

glaciercreek

glenberg

glendive

hanly

haskili

haverdad

haverly

havrelon

hiwan

jugson

kalsted

kirby

krause

laporte

larim

lihen

lisk

lolopeak

lone rock

lowercreek

macfarlane

manning

mccaffery

mcilwaine

mires

mirror

moiese

nelson

nemote

nesda

nippt

oceanet

oraid

ovando

pend orielle

poin

redcreek

rencot

rentsac

rhame

ridge

riedel

riverside

rivra

rochester

ryell

ryorp

sacheen

sachet

sawcreek

scravo

selle

selway

seroco

sheege

shingle

shook

shurley

splitro

stecum

tally

tamely

tassel

terry

tinsley

tipperary

tomichi

travessilla

travson

treble

trembles

trey

tullock

turnercrest

tusier

twilight

upsata

usine

utica

valentine

vebar

victor

virgelle

wabek

wilsonville

woodgulch

woodside

worland

yellowbay

yetull

zeona

NEBRASKA

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within 500 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

alda

almeria

anselmo

bankard

barney

bigwinder

blendon

boel

bolent

boone

brunswick

busher

calamus

canyon

carr

cass

chappell

Cheyenne

craft

dailey

darr

dickinson

dix

doger

draknab

duda

dunday

dwyer

eckley

els

elsmere

fonner

gannett

glenberg

gothenburg

haverson

hedville

hersh

hoffland

holt

inavale

ipage

laird

las animas

lute

manter

marlake

mckelvie

meadin

munjor

o'neill

ord

orphan

ortello

orwet

phiferson

pivot

platte

ronsoh

sarpy

schamber

selia

shingle

simeon

talmo

tassel

thurman

trelona

treon

tryon

tuthill

valent

valentine

white lake

wildhorse

NORTH CAROLINA

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

alaga

alpin

baymeade

biltmore

blanton

bojac

buncombe

butters

cainhoy

candor

carteret

centenary

Charleston

chipley

conetoe

corolla

dragston

duckston

echaw

eustis

foreston

fripp

galestown

immokalee

Johns

kenansville

klej

kureb

lakeland

leon

lillington

louisburg

lynn haven

mandarin

molena

nansemond

newhan

norfolk

ona

osier

.ostin

ousley

pactolus

plummer

pocomoke

potomac

pottsburg

remlik

rimini

rumford

seabrook

st. lucie

suncook

tarboro

toisnot

tomahawk

valhalla

wake

wakulla

wando

wateree

25
MEYMIK15G EPA Reg. No. 87895-

SOIL TYPE RESTRICTION TABLE (continued)

NORTH DAKOTA

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within 500 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

appam

arvilla

aylmer

banks

bantry

beisigl

binford

blackball

blanchard

brandenburg

breien

cabba

Chinook

claire

coe

cohagen

cormant

dast

desart

egeland

ekalaka

falsen

flasher

fleak

fossum

glendive

hamar

hanly

haskill

havrelon

hecla

inkster

karlsruhe

ladner

lemert

lihen

lohnes

maddock

manning

metigoshe

minnewaukan

osakis

poppleton

renshaw

rhame

ruso

schaller

serden

seroco

sioux

stirum

telfer

tinsley

trembles

trey

tusler

twilight

ulen

vebar

venlo

verendrye

virgelle

wabek

wamduska

yecross

yetull

zeona

OHIO

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within 500 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

abscota

algansee

alvin

arkport

barkcamp

bixler

boyer

brady

bronson

casco

coloma

colonie

conotton

dekalb

dixboro

dunbridge

elnora

galen

granby

hazleton

homer

hoopeston

ionia

kingsville

lakin

landes

lanier

maumee

oakville

oshtemo

otisville

ottokee

pernn

pinegrove

plainfield

princeton

rodman

schaffenaker

sisson

sparta

spinks

Stafford

steinsburg

stonelick

ted row

tyner

watertown

SOUTH CAROLINA

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. At planting application only: if MEYMIK 15G is applied to cotton, peanuts or

soybeans as an At-plant application and a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not

apply within 700 feet of a drinking water well unless it is known or reasonably believed based upon authoritative sources that such wells are

either cased to 100 feet below ground level or a minimum of 30 feet below the water table. If it is not known whether the water table is

greater than 25 feet below ground surface, assume that the water table is less than 25 feet below ground surface. Side Dress Application

Only: If MEYMIK 15G is applied to cotton as a Side Dress application only and a vulnerable soil is present and the water table is less than

25 feet below ground surface, do not apply within 700 feet of a drinking water well unless it is known or reasonably believed based upon

authoritative sources that such wells are either cased to 100 feet below ground level or a minimum of 30 feet below the water table. If it is

not known whether the water table is greater than 25 feet below ground surface, assume that the water table is less than 25 feet below

ground surface. Split Application: If MEYMIK 15G is applied to cotton as an At-Plant application and a Side Dress application and a

vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 1 0OP feet of a drinking water well

unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground level

or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

alaga

alpin

baratari

baymeade

blanton

brogdon

buncombe

butters

cainhoy

candor

carteret

centenary

Charleston

chipley

corolla

crevasse

dragston

duckston

echaw

elloree

eustis

foreston

foxworth

fripp

Johns

kenansville

kershaw

kureb

lakeland

leon

louisburg

lynn haven

molena

mouzon

murad

nansemond

newhan

olanta

osier

ousley

pactolus

plummer

pocomoke

ridgeland

rimini

rosedhu

scranton

seabrook

seewee

tarboro

tomahawk

wakulla

wando

wateree

witherbee

26
MEYMIK15G EPA Reg. No. 87895-

SOIL TYPE RESTRICTION TABLE (continued)

SOUTH DAKOTA

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within 500 feet of a drinking water well unless it is known

or reasonably believed based upon author tative sources that such wells are either cased to 1 00 feet below ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

almeria

alwilda

anselmo

arvilla

assinniboine

aylmer

bankard

banks

bantry

beisigl

blackball

blendon

boel

butche

cabba

canyon

cass

chappell

Chinook

cohagen

claire

craft

dailey

dix

doger

dogiecreek

duda

dunday

dwyer

eckley

egeland

ekalaka

els

elsmere

evridge

fedora

flasher

fleak

fossum

gannett

glenberg

glendive

hamar

hanly

hecla

henkin

holt

hopdraw

inavale

ipage

kirby

ladner

las animas

lihen

lute

maddock

manning

manter

marlake

mawer

mccaffery

meadin

minnewaukan

munjor

murdo

o'neill

orton

orwet

platte

renshaw

reva

rhame

rockoa

ronson

sarpy

schamber

serden

seroco

shingle

Simeon

sioux

stirum

storia

talmo

tassel

telfer

thurman

travessilla

trembles

trey

tryon

tusler

tuthill

twilight

ulen

valent

valentine

vebar

venlo

wabek

whitelake

yecross

zeona

TENNESSEE

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

barkcamp

bigbee

bruno

buncombe

crevasse

eustis

nugent

 :

potomac

VIRGINIA

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

alaga

assateague

aura

biltmore

bojac

buncombe

camocca

carteret

catpoint

chipley

conetoe

corolla

dragston

drall

duckston

fisherman

fripp

galestown

Johns

kenansville

klej

kureb

lakehurst

lakeland

lakin

leetonia

leon

magotha

millrock

molena

nansemond

newhan

osier

ousley

pactolus

plummer

pocomoke

remlik

rumford

schaffenaker

seabrook

spessard

tarboro

wakulla

wando

wateree

WEST VIRGINIA

If a vulnerable soil is present and the water table is less than 25 feet below ground surface, do not apply within 300 feet of a drinking water

well unless it is known or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet below ground

level or a minimum of 30 feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface,

assume that the water table is less than 25 feet below ground surface.

drall lakin landes leetonia potomac schaffenaker

27
MEYMIK15G EPA Reg. No. 87895-

SOIL TYPE RESTRICTION TABLE (continued)

WYOMING

If a vulnerable soil is present and the water table is less than 25 feet, do not apply within 500 feet of a drinking water well unless it is known

or reasonably believed based upon authoritative sources that such wells are either cased to 100 feet beiow ground level or a minimum of 30

feet below the water table. If it is not known whether the water table is greater than 25 feet below ground surface, assume that the water

table is less than 25 feet below ground surface.

ashbon

adilis

alcova

alflack

anasazi

anselmo

apeldorn

assinniboine

bankard

banks

barcus

barnum

baroid

barrett

bearmouth

beaverton

bigwin

bigwinder

billycreek

blackball

bobtail

bodorumpe

hosier

bottle

boyle

branham

breece

brownsto

bruja

busher

butche

byrnie

calico tt

cambarge

canwall

carbol

cass

castner

cathedral

cestnik

chappell

cheadle

Chinook

clarkelen

comad

conpeak

cordes

corlett

cotha

cotopaxi

cowestglen

cowood

coyet

cragosen

crestman

crownest

cryluha

curabith

dailey

dast

derrick

devore

dix

draknab

dunday

dunul

dwyer

eckley

edlin

elk mountain

ellicott

emblem

enos

ethelman

eyre

farisita

farson

feltner

fleak

folavar

frontier

gas creek

glenberg

glendive

glenton

grenoble

grieves

grimm

grimstone

gunbarrel

handran

hanks

hanly

hapjack

haterton

haverdad

haverly

havermom

hazton

hechtman

henrieville

herbman

hiland

hiwan

hoot

huguston

irigul

julesburg

kandaly

koonich

labou

lamarsh

lambman

laney

laporte

lariat

larim

las animas

lazear

littlebear

littsan

lone rock

macfarlane

manter

mathers

mccaffery

meadowlake

means

millburne

milok

mishak

mosroc

motoqua

mudray

nathale

nelson

nesda

newfork

nizina

norriston

nolle

oceanet

onason

orphan

otterson

ouray

pahlow

peetz

pendergrass

pepton

pescar

phiferson

pilotpeak

pineguest

poin

preatorson

pugsley

quealman

quealy

randman

ratake

redbank

redcreek

redfeather

rekop

relsob

rencot

reno

rentsac

rivra

rogert

rohonda

roxal

ryark

ryorp

sachet

sawcreek

schamber

schooner

scravo

seedskadee

sharland

sheege

shingle

shoshone

shurley

sobson

southace

southfork

space city

splitro

spool

stecum

sudworth

sunup

taluce

tassel

tasselman

teagulf

teewinot

tellman

tenorio

terada

terro

terry

tetonville

theedle

thermopolis

tieside

tine

tipper

tipperary

tolman

travessilla

travson

trelona

trembles

treoff

treon

trook

troutville

tullock

turnback

turnercrest

twilight

valent

valentine

vible

vonason

walcott

walden

wall

wardboro

wendover

wetmore

whaley

wiggleton

willwood

wilsonville

wint

worf

worfka

worfman

worfstone

worland

yetull

youjay

zeomont

zeona

28