Document ID: EPA-HQ-OPP-2007-0300-0009
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2008-01-09T05:00Z

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460

                                                                     
OFFICE OF 

                                                                 
PREVENTION, PESTICIDES AND

                                                                   
TOXIC SUBSTANCES

  SEQ CHAPTER \h \r 1 								PC Code 	129064, 109702

				DP Barcode	D334937, D334939

MEMORANDUM

DATE:	February 8, 2007

SUBJECT:	Tier I Estimated Environmental Concentrations of
zeta-Cypermethrin for the Use in the Human Health Risk Assessment:  IR-4
Petition for the Use of the Chemical on Okra, Wild Rice, Safflower, and
Citrus (Group 10)

TO:		Sidney Jackson, Risk Manager Reviewer

		Barbara Madden, Team Leader

		Daniel Rosenblatt, Chief 

		Risk Integration Minor Use and Emergency Response Branch

		Registration Division (7505P)

AND:		Dennis McNeilly

		Paula Deschamp, Chief

		Registration Action Branch II

		Health Effects Division (7509P)

FROM:	José Luis Meléndez, Chemist

		Environmental Risk Branch V

		Environmental Fate and Effects Division (7507P)

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

Environmental Risk Branch V

		Environmental Fate and Effects Division (7507P)

This memo presents the Tier I Estimated Surface Drinking Water
Concentrations and Estimated Ground Water Concentrations (EDWCs) for
cypermethrin and zeta-cypermethrin, calculated using the Tier II aquatic
model PRZM/EXAMS and the Tier I aquatic model SCI-GROW, respectively,
for use in the human health risk assessment.  Based on an inspection of
all the uses of zeta-cypermethrin and cypermethrin, it was found that
the use of cypermethrin on cotton is still the use with the major
exposure, and, therefore, the drinking waters assessment results do not
change from the previous one.  An electronic copy of the previous
assessment is attached.  It is noted that the application rates of
zeta-cypermethrin are around half those of cypermethrin.  The maximum
application rate per season of zeta-cypermethrin is 0.3 lb
a.i./A/season, while the maximum application rate of cypermethrin is 0.6
lb a.i./A/season.  Therefore, the drinking waters assessment for
cypermethrin should cover both, zeta-cypermethrin, and cypermethrin.

The Estimated Drinking Water Concentrations (EDWCs) for cypermethrin
were calculated based on a maximum application rate of 0.6 lb
a.i./A/season of cypermethrin. The acute drinking water concentration in
surface water is 1.04 ppb of cypermethrin, based on applications of the
chemical to cotton.  The cancer/chronic drinking water concentration is
0.013 ppb (based on applications of cotton, with the highest application
rate).  The SCI-GROW generated EDWC is 0.0036 ppb of cypermethrin, which
is recommended for use, both for acute and chronic exposures. 

Table 1 provides a summary of the Tier II modeled drinking water
concentrations. 

Table 1.  Maximum Tier II Estimated Drinking Water Concentrations
(EDWCs) for drinking water risk assessment based on aerial application
of cypermethrin on cotton.

DRINKING WATER SOURCE (MODEL USED) 	USE (rate modeled)	MAXIMUM ESTIMATED
DRINKING WATER CONCENTRATION  (EDWC)  ( ppb) 

Groundwater (SCI-GROW)	Cotton (0.6 lb. a.i./A/season)	Acute and Chronic
0.0036

Surface water  (PRZM/EXAMS)	NC cotton (0.6 lb. a.i./A/season)	Acute	1.04

	NC cotton (0.6 lb. a.i./A/season)	Chronic	              0.013          

Use Characterization

Table 2 is an updated summary of all agricultural use patterns for
zeta-cypermethrin.  The bolded uses are those proposed new ones.  The
use information was obtained from the proposed labels for Fury 2EC
Insecticide and Mustang Insecticide.

Table 2.  Summary use information for zeta-cypermethrin, based on labels
for Fury® EC Insecticide and Mustang® Insecticide (proposed new uses
are in bold).

Use	

Single  App. Rate (lb a.i./A)	

Number of Apps.	

Seasonal App. Rate (lb a.i./A)	Interval Between Apps. (days)	

App. Method	Incorpo-ration Depth (inches)

Already existing crops in the labels for zeta-cypermethrin:

Alfalfa	0.05	3	0.15	7	G, A, ULV	0

Brassica Vegetables	0.05	6	0.3	7	G, A	0

Bulb Vegetables	0.05	5	0.25	7	G, A	0

Sweet corn	0.05	6	0.3	3	G, A	0

Corn	0.05	4	0.2	3	G, A	0

Cotton	0.05	6	0.3	3	G, A	0

Fruiting Vegetables	0.05	6	0.3	7	G, A	0

Legume Vegetables	0.05	6	0.3	5	G, A	0

Head lettuce	0.05	6	0.3	NS	G, A	0

Pecans	0.05	6	0.3	NS	G	0

Rice	0.05	4	0.2	7	G, A	0

Sorghum	0.05	5	0.25	10	G, A	0

Soybeans	0.05	6	0.3	7	G, A	0

Sugarcane	0.05	4	0.2	21	G, A	0

Wheat	0.05	5	0.25	14	G, A	0

Cilantro	0.05	6	0.3	7	G, A	0

Head and Steam Brassica Vegetables	0.05	6	0.3	7	G, A	0

Leafy Vegetables (except Brassica)	0.05	6	0.3	7	G, A	0

Sunflowers	0.05	5	0.25	NS	G, A	0

Grass forage, fodder, hay group	0.05	4	0.2	7	G, A	0

Canola, Rapeseed	0.05	4	0.2	7	G, A	0

Barley	0.05	5	0.25	14	G, A	0

Grapes	0.05	6	0.3	7	G, A	0

Tree nut group (almond, pecan)	0.05	5	0.25	7	G, A	0

Berries	0.05	6	0.3	7	G	0

Peanuts	0.05	6	0.3	NS	G, A	0

Root and Tuber Vegetables	0.05	6	0.3	NS	G, A	0

Cucurbit Vegetable Group	0.05	6	0.3	NS	G, A	0

Non-grass animal feeds (forage, fodder, straw and hay)	0.05	3	0.15	7	G,
A	0

Turf1	0.225	1	0.225	N/A	G	0

Pome fruits	0.05	6	0.3	7	G	0

Stone fruits	0.05	6	0.3	7	G	0

Citrus 

(Group 10)	0.05	4	0.20	14	G, A	0

Wild Rice	0.05	4	0.20	7	G, A	0

Okra	0.05	6	0.3	7	G, A	0

Safflower	0.05	3	0.15	14	G, A	0

G=ground; A=aerial; ULV=ultra low volume application; NS=Not specified.

1 For use on residential lawns, home perimeter, ornamental and flower
gardens.





UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460

                                                                     
OFFICE  OF 

                                                                 
PREVENTION, PESTICIDES AND

                                                                   
TOXIC SUBSTANCES

PC Code 	109702

DP Barcode	D289428

COPY

MEMORANDUM

DATE:	May 02, 2005

SUBJECT:	Tier II Estimated Environmental Concentrations of Cypermethrin
for the Use in the Human Health Risk Assessment.

TO:		Cathryn O’Connell, Chemical Review Manager

Margaret Rice, Branch Chief

Reregistration Branch II

Special Review and Reregistration Division (7508C)

AND:		William Donovan, Risk Assessor

Reregistration Branch III

Health Effects Division (7509C)

FROM:	José Luis Meléndez, Chemist

Environmental Risk Branch V

Environmental Fate and Effects Division

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

Environmental Risk Branch V

Environmental Fate and Effects Division (7507C)

This memo presents the Estimated Surface Drinking Water Concentrations
and Estimated Ground Water Concentrations (EDWCs) for CYPERMETHRIN,
calculated using the Tier 2 aquatic model PRZM/EXAMS and the Tier 1
aquatic model SCI-GROW, respectively, for use in the human health risk
assessment.

The Estimated Drinking Water Concentrations (EDWCs) for cypermethrin
were calculated based on a maximum application rate of 0.6 lb
a.i./A/season. The acute drinking water concentration in surface water
is 1.04 ppb of cypermethrin.  The cancer/chronic drinking water
concentration is 0.013 ppb, using the NC cotton scenario.  These values
represent the mean value over a 30-year period.  Various other scenarios
were also explored (CA, MS and TX cotton, CA onion and CA lettuce), but
they consistently yielded lower EDWCs.  The SCI-GROW generated EDWC (for
cotton or lettuce, highest application rate) is 0.0036 ppb of
cypermethrin, which is recommended for use, both for acute and chronic
exposures.



1.	Introduction 

Cypermethrin is a pyrethroid insecticide with both agricultural and non
agricultural applications. For agricultural uses in the United States,
cypermethrin is predominantly used to control pests on cotton, lettuce,
pecans and onions, with the predominant use being cotton (80% of the
total agricultural usage).  It may be used alone or in conjunction with
organophosphate pesticides to control pests such as budworm and bollworm
populations on cotton and worms and aphids on lettuce.  Application
rates and the timing of these applications vary by crop type.  Non
agricultural uses of cypermethrin include pest management inside
greenhouses, food processing, storage, and dairy facilities (non contact
food uses only), wood treatment applications, animal kennels, commercial
storage facilities, automobile and taxi services, and applications to
drainage systems.

Cypermethrin is expected to have little mobility in soil surfaces and
leaching into groundwater is not expected to be an important
environmental fate process (mean Koc=141,700).  Volatilization is not
expected to be an important transport process since cypermethrin has a
relatively low vapor pressure and Henry’s Law constant (2.5x10-9 mm Hg
and 3.4x10-7 Atm-m3/mole, respectively).  Cypermethrin is moderately
persistent in the environment and degrades through a combination of
biotic and abiotic mechanisms.  Cypermethrin hydrolyzes slowly at acidic
and neutral pH, but degrades in a matter of days under alkaline
conditions.  Cypermethrin is more light stable than the first or second
generation pyrethroids like allethrin and resmethrin, but still
undergoes photolysis in water, with half-lives of about a month or more
in distilled water (half-life 36.2 days).  The rate of photolysis
appears to be enhanced in natural waters (which contain photosensitizing
agents like humic and fulvic acids), where the accelerated degradation
results in half-lives of a few days or less.  Under both aerobic and
anaerobic soil metabolism conditions, cypermethrin biodegrades
relatively slowly, with half-lives on the order of about 2 months, but
in aquatic metabolism conditions, it biodegrades more rapidly, with
half-lives on the order of one to two weeks.  The primary degradation
products of cypermethrin are cis- and trans-DCVA [(±)cis- or
trans-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane carboxylic acid],
3-phenoxybenzaldehyde, and 3-PBA [3-phenoxybenzoic acid].  They result
from cleavage of the ester linkage of the cypermethrin molecule.

Estimated Drinking Water Concentrations (EDWC) were calculated for
groundwater and surface water utilizing the tier 1 aquatic model
SCI-GROW, and tier 2 aquatic model PRZM/EXAMS, respectively.

2.	SCI-GROW

The tier 1 aquatic model SCI-GROW was employed to estimate levels of
cypermethrin that may potentially reach groundwater.  SCI-GROW is a
screening model which is used to estimate pesticide concentrations in
vulnerable ground water.  Pesticide concentrations estimated by SCI-GROW
represent conservative or high-end exposure values because the model is
based on ground-water monitoring studies which were conducted by
applying pesticides at maximum allowed rates and frequency, to
vulnerable sites (i.e., shallow aquifers, sandy, permeable soils, and
substantial rainfall and/or irrigation to maximize leaching). In most
cases, the majority of the use areas will have ground water that is less
vulnerable to contamination than the areas used to derive the SCI-GROW
estimate.  The SCI-GROW input parameters for cypermethrin are shown in
Table 1.  The SCI-GROW output file is shown in Appendix C.

Table 1.  SCI-GROW Input Parameters and Estimated Environmental
Concentration of Cypermethrin in Groundwater

PARAMETER	

VALUE	

SOURCE

Application rate (lbs a.i./A)	

0.1			

Product Label: Ammo 2.5 EC (EPA Reg. No. 279-3027), and Mustang (EPA
Reg. No. 279-3126)

Number of applications	

6	

Product Label: Ammo 2.5 EC (EPA Reg. No. 279-3027), and Mustang (EPA
Reg. No. 279-3126)

Koc	

20,800	

MRID 42129002 and 42129003 (lowest value, there is greater than
three-fold variation among values)

Soil aerobic half-life (days)	

60.2	

MRID 42156601

Estimated Groundwater concentration (ppb)	

0.0036	

Output value from SCI-GROW

For the SCI-GROW model, if the Koc range has greater than 3-fold
variation in the values, the lowest value is employed.  It is also noted
that estimated concentrations of chemicals with Koc values greater than
9995 mL/g  are beyond the scope of the regression data used in SCI-GROW
development.  The maximum application rate for cypermethrin of 0.1 lbs
a.i./A for six applications per season was chosen.  This maximum
seasonal application rate is representative of various crops such as
cotton and lettuce, considered in this assessment.

3.	PRZM/EXAMS Drinking Water Concentrations

The tier 2 linked model PRZM/EXAMS was employed to calculate surface
water concentrations (EDWCs) of cypermethrin in an index reservoir,
which is used for assessment of vulnerable surface drinking water
sources.  The Index Reservoir is intended as a drop-in replacement for
the standard pond for use in drinking water assessments.  It is used in
a manner similar to the standard pond except that flow rates are
calibrated to be consistent with local weather conditions. The
morphology of the reservoir and its watershed are designed to correspond
with those of Shipman City Lake, a small reservoir in Illinois selected
to represent small runoff-vulnerable drinking water surface supplies in
agricultural areas. It is noted that the surface water concentrations
generated from EXAMS were multiplied by Percent Crop Area (PCA) factors.
 In 1999, EFED proposed using PCA factors in pesticide exposure
assessments to account for the fact that a watershed of sufficient size
to supply a drinking water source is not likely to be devoted entirely
to growing crops (EPA 2003a).  Generally a PCA factor of 0.87 is
employed in drinking water assessments unless the assessment is for a
crop for which there is a refined PCA estimate.  In this Drinking Water
Assessment, the EDWCs were obtained by multiplication of the output
concentration of PRZM/EXAMS by 0.20 for the cotton scenarios and 0.87
for the CA onion and CA lettuce crop scenarios.  The PRZM/EXAMS input
parameters are shown in Tables 2 and 3.  They were selected according to
current EFED guidelines for the selection of input parameters for
aquatic models.  The output files from the PRZM/EXAMS runs are provided
in Appendix C.

Table 2.  PRZM/EXAMS Input Parameters for Cypermethrin used in the
Drinking Water Assessment.

PARAMETER	

VALUE	

SOURCE

Maximum Individual Application Rate/ Number of Applications Per Season/
Minimum Interval Between Applications/ Application Date	

Refer to Table 3 for details.	

Crop specific.  According to the label and, application date according
to common agricultural practices.

Aerobic soil metabolism	

	62 days	

MRID 42156601 (90% C.L. on the mean, n = 2 observations)

Koc	

	141,700

	

MRID 42129002 and 42129003 (mean value, n = 4)

Henry’s law constant	

	3.4x10-7 atm-m3/mol	

Laskowski (2002)

Aerobic Aquatic Metabolism	

      11.3 days

	

MRID  44876106 (90% C.L. on the mean, n = 2 observations)

Anaerobic Aquatic Metabolism	

	19.3 days

	

MRID  44876105 (90% C.L. on the mean, n = 2 observations)

Aqueous photolysis	

	36.2 days	

MRID  42395701

Hydrolysis half-life (days)	pH 5

	pH 7

	pH 9	

	stable

stable

1.90 days	

MRID  42620501

Molecular weight	

	416.3 g/mole	

Laskowski (2002)

Solubility (WSOL)	

	0.040 ppm	

Laskowski (2002) (solubility x 10)

Vapor pressure (VP)	

	2.5x10-9 mm Hg	

Laskowski (2002)

PLDKRT (foliage pesticide rate constant)	

0.13 days-1	

Willis and McDowell 1987

FEXTRC (foliar extraction)	

0.5

	

EFED Model Input Guidance, Version II (2002)

FILTRA (filtration parameter; required if CAM set to 3)	

NA	

--

PLVKRT (pesticide decay rate on plant foliage)	

0/day 	

EFED Model Input Guidance, Version II (2002)

CAM (chemical application method)	

2 	

Reflects foliar application

UPTKF (plant uptake factor)	

0	

EFED Model Input Guidance, Version II (2002)

IPSCND	

                            1	

Surface Applied

Application efficiency	

	0.95	

EFED Model Input Guidance, Version II (2002)

spray drift	

	0.16	

EPA (2003a). Default used for Drinking Water Assessments for aerial
applications 

PCA	

                  Cotton - 0.20

         Lettuce and Onion - 0.87	

EPA (2003a). 

Four PRZM scenarios were modeled for cotton crop usage : California,
Mississippi, North Carolina and Texas.  Each of these were modeled using
the same application rates and use patterns.  The California scenario is
based on data from Fresno County in the Central Valley region.  The
Mississippi scenario arises from Yazoo County.  The North Carolina PRZM
scenario is representative of the Piedmont/Coastal Plain region.  The
Texas scenario is typically planted in the spring with crop maturity
occurring roughly 4 months after the planting date.  While late season
planting can occur up to June in many southern states, it is not
advisable to begin planting after mid May because of the steep decline
in yield (the best yields usually occur with early season planting,
optimal soil temperature and moisture and air temperature).  Harvest
typically occurs from September 1, through December.  It is not
advisable to use pyrethroid insecticides on cotton crops prior to July 1
unless infestations are high in order to avoid insect resistance later
in the season (Roof 2004).

The field used to represent onion production in California is located in
Kern County in the San Joaquin Valley, although onion production areas
are quite extensive (San Joaquin, Coastal-Intermediate Region, Imperial
Valley, southern and central coastal regions, the high desert areas of
Los Angeles County and the northern mountain valleys).  Bulb onions are
planted from September through May and harvesting begins in April or May
and completed by September.

Only one validated PRZM scenario currently exists for lettuce
(California).  Lettuce is a year-round crop in California, so the
application timing of cypermethrin can vary (Jackson et.al. 1996).

Table 3.  Crop Usage Patterns for Cypermethrin on Cotton, Onions, and
Lettuce1

Crop or

Crop Group	

Maximum Individual

Application Rate

(lb a.i./A)	

Number of

Applications

per season	

Minimum

 Application Interval

(days)	

Application Date

(typical agricultural practices)

Cotton	

0.1 (0.112 kg/ha)	

6	

3	

July 1st

Onion	

0.1 (0.112 kg/ha)	

5	

7	

May 10th

Lettuce	

0.1 (0.112 kg/ha)	

6	

7	

August 1st

(1). Data obtained from label for Ammo 2.5 EC (EPA Reg. No. 279-3027).

EDWCs are summarized in Table 4.  

  EDWC for Cypermethrin (ppb or μg/L) Obtained from PRZM/EXAMS.

Site and Crop		

Peak	

Annual Average (Cancer/Chronic)

Californiaa Cotton	

0.12	

0.003

Mississippia Cotton	

0.47	

0.009

North Carolinaa Cotton	

1.04	

0.013

Texasa Cotton	

0.24	

0.005

Californiab Onion	

0.45	

0.013

Californiab Lettuce	

0.60	

0.027

a.  PRZM/EXAMS EDWC multiplied by 0.20 (PCA for cotton).

b.  PRZM/EXAMS EDWC multiplied by 0.87 (PCA for other crops).

Appendix A.	Background Information on SCI-GROW and PRZM/ EXAMS, and
PRZM Scenarios

BACKGROUND INFORMATION ON SCI-GROW

SCI-GROW  V.2.3 provides a groundwater screening exposure value to be
used in determining the potential risk to human health from drinking
water contaminated with the pesticide.  Since the SCI-GROW
concentrations are likely to be approached in only a very small
percentage of drinking water sources, i.e., highly vulnerable aquifers,
it is not appropriate to use SCI-GROW for national or regional exposure
estimates.

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

Estimated concentrations of chemicals with KOC values greater than 9995
ml/g are beyond the scope of the regression data used in SCI-GROW
development.  If there are concerns for such chemicals, a higher tier
groundwater exposure assessment should be considered, regardless of the
concentration returned by SCI-GROW.

BACKGROUND INFORMATION ON PRZM/EXAMS

The Tier II aquatic model employs PRZM (Pesticide Root Zone Model;
version 3.12 Beta compiled May 24, 2001) and EXAMS (Exposure Analysis
Modeling System; version 2.98.04 compiled November 12, 2002).  PRZM
simulates processes such like runoff and erosion from an agricultural
field on a daily time step.  The runoff and erosion flux output data
from PRZM are used as chemical loadings to the EXAMS surface water
program in order to predict the EECs.  A graphical user interface
(pe4v01.pl) developed by the EPA (http://www.epa.gov/oppefed1/
models/water) was used to facilitate inputting chemical and use specific
parameters into the appropriate PRZM input files (inp) and EXAMS
chemical files.

PRZM is a one-dimensional, dynamic, compartmental model that can be used
to simulate chemical movement in unsaturated soil systems within and
immediately below the plant root zone.  It has two major components: 
hydrology (and hydraulics) and chemical transport.  The hydrologic
component for calculating runoff and erosion is based on the Soil
Conservation Service curve number technique and the Universal Soil Loss
Equation.  Evapotranspiration is estimated either directly from pan
evaporation data, or based on an empirical formula.  Water movement is
simulated by the use of generalized soil parameters, including field
capacity, wilting point, and saturation water content.  

The chemical transport component can simulate pesticides or other
chemicals.  For pesticides, the transport component can simulate
pesticide application on the soil or on the plant foliage. 
Biodegradation can also be considered in the root zone.  Dissolved,
adsorbed, and vapor-phase concentrations in the soil are estimated by
simultaneously considering the processes of pesticide uptake by plants,
surface runoff, erosion, decay, volatilization, foliar washoff,
advection, dispersion, and retardation.  For nitrogen, simulation of
surface applications, atmospheric deposition, and septic effluent
discharge may all be simulated.

EXAMS is a model that has a set of process modules that link fundamental
chemical properties to limnological processes that control the kinetics
and transport of chemicals in aquatic systems. It provides facilities
for steady state or long-term evaluation of chronic chemical discharges,
initial-value approaches for studying short-term contaminant releases,
and full kinetic simulations that allow for monthly variation in mean
climatological factors, and changes in contaminant loadings on daily
time scales.  It is fairly and relatively complex model that requires
more input variables, ranging from hydro-geological and weather data to
pesticide physicochemical properties, mobility coefficients, and
degradation rate constants in the aqueous and sediment phases.

PRZM CROP SCENARIOS:

Four PRZM scenarios exist for cotton crop usage : California,
Mississippi, North Carolina and Texas.  Each of these were modeled using
the same application rates and use patterns.  The California scenario is
based on data from Fresno County in the Central Valley region using a
Twisselman clay as the representative soil for this region.  This soil
is a fine, mixed, calcareous, thermic Typic Torriorthents of hydrologic
group C.  The Mississippi scenario arises from Yazoo County and uses a
Loring silt loam as the representative soil. Loring silt loam is a
fine-silty, mixed, active, thermic, Qxyaquic Fragiudalfs of hydrologic
group C.  The representative soil in the North Carolina PRZM scenario is
a Boswell fine sandy loam of hydrologic group D, characteristic of the
Piedmont/Coastal Plain region.  The soil selected to simulate the Texas
scenario is a Crockett fine sandy loam. Crockett fine sandy loam is a
fine, smectitic, thermic Udertic Paleustalfs of hydrologic group C. 
Since cotton growth requires a relatively long period of warm
temperatures (190-210 days at temperatures of 60 oF and above), it is
typically planted in the spring with crop maturity occurring roughly 4
months after the planting date.  While late season planting can occur up
to June in many southern states, it is not advisable to begin planting
after mid May because of the steep decline in yield (the best yields
usually occur with early season planting, optimal soil temperature and
moisture and air temperature).  Harvest typically occurs from September
1, through December.  It is not advisable to use pyrethroid insecticides
on cotton crops prior to July 1 unless infestations are high in order to
avoid insect resistence later in the season (Roof 2004).  

The field used to represent onion production in California is located
in Kern County in the San Joaquin Valley, although onion production
areas are quite extensive (San Joaquin, Coastal-Intermediate Region,
Imperial Valley, southern and central coastal regions, the high desert
areas of Los Angeles County and the northern mountain valleys). 
According to the 1997 Census of Agriculture, California is the major
producer of onions for the market.  Bulb onions are planted from
September through May and harvesting begins in April or May and
completed by September. Onions are cools season, biennial plants that
are commercially grown as an annual.  Plant canopy can approach 100
percent in some narrow row fields grown under drip irrigation. 
Irrigation is required to avoid seed or plant dry out.  Onions can grow
on a wide range of soils.  The soil selected to represent the field is
Ciervo clay.  Ciervo clay, is a fine, semetic, thermic Vertic
Haplocambids.  These soils are often used for onion and other truck crop
production under irrigation.  The Ciervo clay has very slow
permeability.  Ciervo clay is a Hydrologic Group D soil.

Only one validated PRZM scenario currently exists for lettuce
(California).  The representative soil type is a Placentia sandy loam
(hydrologic Group D).  Lettuce is a year-round crop in California, so
the application timing of cypermethrin can vary (Jackson et al. 1996). 
Lettuce is usually planted at depths of approximately 1/8 to 1/4 inches
primarily on 40-inch raised beds with 2 seedlines per bed.  For a
midsummer planting, the harvest usually begins 70-80 days later and
cypermethrin is typically foliar applied as needed following emergence.

Appendix B.  References

EPA 2003a.  Use of Regional Percent Crop Area Factors in Refined
Drinking Water Assessments.  US EPA Office of Pesticide Programs (OPP)
Environmental Fate and Effects Division (EFED) Water Quality Technical
Team (WQTT) July 25, 2003

EPA 2003b.  Pesticide Root Zone Model Field and Orchard Crop Scenario
Metadata.  February 06, 2003

Gorsuch CS.  Clemson University Pest Management Handbook. Fruits and
Nuts (last updated 3-11-2003).  
http://cufan.clemson.edu/pmguide/main.htm		

Jackson L., Mayberry K., Laemmlen F., Koike S., Schulbach K., Chaney W. 
Iceberg lettuce production in California.  Vegetable Research and
Information Center Univ of California Div of Agriculture and Natural
Resources.  Publication Number 7215 (1996).

Laskowski D.A.  2002.  Physical and Chemical Properties of Pyrethroids. 
Rev. Environ. Contam. Toxicol.  174:49-170

NCFAP. 2003.  National Center for Food and Agricultural Policy, National
Pesticide Use Database.  Information taken on February 28, 2005 from the
website: http://www.ncfap.org/database/default.htm.

Roof ME.  Clemson University Pest Management Handbook. Cotton Insect
Control (last updated 5-26-2004).  
http://cufan.clemson.edu/pmguide/main.htm

Tomlin C.  1994.  Pesticide Manual 10th edition.  British Crop
Protection Council.  The Royal Society of Chemistry, Cambridge U.K.

Willis and McDowell 1987, as cited in Carsel, R.F., et.al., “PRZM-3, A
Model for Predicting Pesticide and Nitrogen Fate in the Crop Root and
Unsaturated Soil Zones: User’s Manual for Release 3.0.”  National
Exposure Research Laboratory USEPA, Athens, GA; AQUA TERRA Consultants,
Mountain View, CA; and Waterborne Environmental, Inc., Leesburg, VA. p.
5-12. 



Appendix C.  Output files from SCI-GROW and PRZM/EXAMS

SCI-GROW

                           SCIGROW

                          VERSION 2.3

            ENVIRONMENTAL FATE AND EFFECTS DIVISION

                 OFFICE OF PESTICIDE PROGRAMS

             U.S. ENVIRONMENTAL PROTECTION AGENCY

                        SCREENING MODEL

                FOR AQUATIC PESTICIDE EXPOSURE

 

 SciGrow version 2.3

 chemical:Cypermethrin

 time is  5/ 2/2005  14:37:25

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

  Application      Number of       Total Use    Koc      Soil Aerobic

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

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

      0.100           6.0           0.600      2.08E+04       60.2

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

 groundwater screening cond (ppb) =   3.60E-03*

 *Estimated concentrations of chemicals with Koc values greater than
9995 ml/g

 are beyond the scope of the regression data used in SCI-GROW
development.

 If there are concerns for such chemicals, a higher tier groundwater
exposure

 assessment should be considered, regardless of the concentration
returned

 by SCI-GROW.

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

 

PRZM/EXAMS

Note:  The output concentrations have not been adjusted by the PCA
factor in these files. The adjustment is reflected in table 4

Cotton California

stored as CottonCA.out

Chemical: Cypermethrin					

PRZM environment: CAcottonC.txt	modified Friday, 6 December 2002 at
06:50:06

EXAMS environment: ir298.exv	modified Thuday, 29 August 2002 at 10:34:12

Metfile: w93193.dvf	modified Wedday, 3 July 2002 at 04:04:24

Water segment concentrations (ppb) 

Year	Peak	96 hr	21 Day	60 Day	90 Day	Yearly

1961	0.6109	0.3484	0.2565	0.0991	0.06724	0.01687

1962	0.6129	0.3508	0.2589	0.1006	0.06837	0.01731

1963	0.6166	0.3549	0.2622	0.1028	0.06998	0.01773

1964	0.6127	0.3504	0.2586	0.1004	0.06829	0.01724

1965	0.6149	0.3529	0.2606	0.1017	0.06925	0.01755

1966	0.6157	0.3539	0.2614	0.1019	0.06919	0.01751

1967	0.6085	0.3457	0.2548	0.09772	0.06605	0.01661

1968	0.6109	0.3484	0.257		0.09969	0.06785	0.01713

1969	0.6128	0.3506	0.2587	0.1005	0.06825	0.01748

1970	0.6093	0.3466	0.2555	0.09847	0.0668	0.01694

1971	0.611		0.3486	0.2571	0.09934	0.06738	0.01701

1972	0.6121	0.3497	0.2581	0.09996	0.06788	0.01715

1973	0.6133	0.3511	0.2592	0.1008	0.06857	0.0174

1974	0.6124	0.3501	0.2584	0.1002	0.06803	0.01717

1975	0.6161	0.3544	0.2618	0.1027	0.07004	0.01773

1976	0.6148	0.3528	0.2605	0.1023	0.07011	0.01797

1977	0.6108	0.3483	0.2569	0.09921	0.06726	0.017

1978	0.6102	0.3476	0.2563	0.0988	0.06713	0.01693

1979	0.611		0.3485	0.2571	0.09938	0.06733	0.01688

1980	0.6087	0.3458	0.2549	0.09805	0.06642	0.01666

1981	0.6073	0.3443	0.2537	0.09711	0.06564	0.01646

1982	0.6129	0.3507	0.2588	0.1004	0.0683	0.01731

1983	0.6154	0.3536	0.2611	0.1016	0.06884	0.01743

1984	0.6034	0.3398	0.25		0.09496	0.06402	0.01595

1985	0.6052	0.3419	0.2517	0.09617	0.06512	0.01636

1986	0.611		0.3485	0.2571	0.09891	0.0669	0.01686

1987	0.6182	0.3567	0.2637	0.1034	0.07033	0.0177

1988	0.6054	0.3422	0.2519	0.09625	0.06509	0.01629

1989	0.6098	0.3472	0.256		0.09878	0.06705	0.01685

1990	0.608		0.3451	0.2543	0.09766	0.06612	0.01662

Sorted results

Prob.	Peak		96 hr		21 Day	60 Day	90 Day	Yearly

0.1	0.61606	0.35435	0.26176	0.10266	0.070034	0.017727

Average of yearly averages:	0.01707

Inputs generated by pe4.pl - 8-August-2003

Data used for this run:

Output File: CottonCA

Metfile:	w93193.dvf

PRZM scenario:	CAcottonC.txt

EXAMS environment file:	ir298.exv

Chemical Name:	Cypermethrin

Description	Variable Name	Value	Units	Comments

Molecular weight	mwt	416.3	g/mol

Henry's Law Const.	henry	3.4e-7	atm-m^3/mol

Vapor Pressure	vapr	2.5e-9	torr

Solubility	sol	0.04	mg/L

Kd	Kd		mg/L

Koc	Koc	141700	mg/L

Photolysis half-life	kdp	36.2	days	Half-life

Aerobic Aquatic Metabolism	kbacw	11.3	days	Halfife

Anaerobic Aquatic Metabolism	kbacs	19.3	days	Halfife

Aerobic Soil Metabolism	asm	62	days	Halfife

Hydrolysis:	pH 5	0	days	Half-life

Hydrolysis:	pH 7	0	days	Half-life

Hydrolysis:	pH 9	1.9	days	Half-life

Method:	CAM	2	integer	See PRZM manual

Incorporation Depth:	DEPI	0	cm

Application Rate:	TAPP	0.112	kg/ha

Application Efficiency:	APPEFF	0.95	fraction

Spray Drift	DRFT	0.16	fraction of application rate applied to pond

Application Date	Date	1-7	dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1	interval	3	days	Set to 0 or delete line for single app.

Interval 2	interval	3	days	Set to 0 or delete line for single app.

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

Interval 4	interval	3	days	Set to 0 or delete line for single app.

Interval 5	interval	3	days	Set to 0 or delete line for single app.

Record 17:	FILTRA	

IPSCND	1

UPTKF	

Record 18:	PLVKRT	

PLDKRT	0.13

FEXTRC	0.5

Flag for Index Res. Run	IR	IR

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

Write Benthic Porewater File?	benthic	0

Write Benthic Sediment File?	benthicsed	0

Cotton Mississippi

stored as CottonMS.out

Chemical: Cypermethrin

PRZM environment: CAonionC.txt	modified Monday, 23 December 2002 at
05:48:48

EXAMS environment: ir298.exv	modified Thuday, 29 August 2002 at 10:34:12

Metfile: w03940.dvf	modified Wedday, 3 July 2002 at 04:05:46

Water segment concentrations (ppb) 

Year	Peak		96 hr		21 Day	60 Day	90 Day	Yearly

1961	1.294		0.8689	0.4102	0.2243	0.1601	0.04901

1962	0.7856	0.4131	0.2657	0.1317	0.1018	0.03352

1963	2.187		1.036		0.4336	0.1766	0.1212	0.03677

1964	1.24		0.5311	0.3216	0.1919	0.1415	0.05652

1965	2.26		1.176		0.3197	0.1456	0.1579	0.05247

1966	1.734		0.7583	0.2785	0.2056	0.1549	0.04914

1967	0.687		0.3941	0.3014	0.1571	0.1182	0.03941

1968	0.6447	0.3617	0.2586	0.1339	0.09727	0.03297

1969	1.509		0.6197	0.3031	0.181		0.1295	0.03999

1970	1.036		0.4287	0.2561	0.1404	0.1331	0.05081

1971	1.138		0.5153	0.335		0.1948	0.1612	0.05147

1972	0.6268	0.355		0.2627	0.1317	0.0973	0.03513

1973	0.6045	0.3406	0.2508	0.1086	0.08734	0.03431

1974	0.6383	0.3615	0.2591	0.1352	0.1185	0.04385

1975	3.933		1.602		0.5744	0.325		0.2379	0.07385

1976	0.8993	0.5919	0.3304	0.1707	0.1447	0.04671

1977	1.08		0.6076	0.3262	0.175		0.1371	0.04835

1978	0.9796	0.56		0.315		0.1313	0.09914	0.03721

1979	3.381		1.565		0.7158	0.3673	0.2747	0.08552

1980	0.612		0.3393	0.2636	0.1153	0.08078	0.03044

1981	1.287		0.6196	0.3348	0.1415	0.1139	0.03842

1982	2.043		0.9086	0.513		0.3084	0.216		0.07078

1983	1.08		0.4434	0.272		0.149		0.1118	0.04244

1984	1.492		0.7043	0.3354	0.1887	0.1363	0.05006

1985	2.36		0.9698	0.3074	0.2285	0.1714	0.05328

1986	1.327		0.5493	0.3526	0.1695	0.1274	0.04415

1987	0.6063	0.3427	0.2592	0.1366	0.09617	0.03237

1988	0.9502	0.5307	0.3062	0.1462	0.1057	0.04024

1989	0.8184	0.48		0.3186	0.1355	0.1048	0.04127

1990	0.6208	0.3517	0.2592	0.103		0.08958	0.03481

Sorted results

Prob.	Peak	96 hr	21 Day	60 Day	90 Day	Yearly

0.1	2.35	1.162	0.50506	0.30041	0.21154	0.069354

Average of yearly averages:	0.0458423333333333

Inputs generated by pe4.pl - 8-August-2003

Data used for this run:

Output File: CottonMS

Metfile:	w03940.dvf

PRZM scenario:	CAonionC.txt

EXAMS environment file:	ir298.exv

Chemical Name:	Cypermethrin

Description	Variable Name	Value	Units	Comments

Molecular weight	mwt	416.3	g/mol

Henry's Law Const.	henry	3.4e-7	atm-m^3/mol

Vapor Pressure	vapr	2.5e-9	torr

Solubility	sol	0.04	mg/L

Kd	Kd		mg/L

Koc	Koc	141700	mg/L

Photolysis half-life	kdp	36.2	days	Half-life

Aerobic Aquatic Metabolism	kbacw	11.3	days	Halfife

Anaerobic Aquatic Metabolism	kbacs	19.3	days	Halfife

Aerobic Soil Metabolism	asm	62	days	Halfife

Hydrolysis:	pH 5	0	days	Half-life

Hydrolysis:	pH 7	0	days	Half-life

Hydrolysis:	pH 9	1.9	days	Half-life

Method:	CAM	2	integer	See PRZM manual

Incorporation Depth:	DEPI	0	cm

Application Rate:	TAPP	0.112	kg/ha

Application Efficiency:	APPEFF	0.95	fraction

Spray Drift	DRFT	0.16	fraction of application rate applied to pond

Application Date	Date	1-7	dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1	interval	3	days	Set to 0 or delete line for single app.

Interval 2	interval	3	days	Set to 0 or delete line for single app.

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

Interval 4	interval	3	days	Set to 0 or delete line for single app.

Interval 5	interval	3	days	Set to 0 or delete line for single app.

Record 17:	FILTRA	

IPSCND	1

UPTKF	

Record 18:	PLVKRT	

PLDKRT	.13

FEXTRC	0.5

Flag for Index Res. Run	IR	IR

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

Write Benthic Porewater File?	benthic	

Write Benthic Sediment File?	benthicsed	

Cotton North Carolina

stored as CottonNC.out

Chemical: Cypermethrin

PRZM environment: NCcottonC.txt	modified Friday, 6 December 2002 at
08:14:40

EXAMS environment: ir298.exv	modified Thuday, 29 August 2002 at 10:34:12

Metfile: w13722.dvf	modified Wedday, 3 July 2002 at 04:05:50

Water segment concentrations (ppb) 

Year	Peak		96 hr		21 Day	60 Day	90 Day	Yearly

1961	1.822		0.8207	0.3655	0.269		0.2069	0.05829

1962	2.846		1.274		0.7578	0.353		0.2549	0.0783

1963	1.125		0.494		0.2877	0.1376	0.09743	0.04555

1964	2.09		0.968		0.4298	0.275		0.238		0.07862

1965	2.719		1.323		0.5334	0.3374	0.2443	0.07185

1966	2.355		0.9852	0.4319	0.2559	0.1913	0.05691

1967	1.998		0.8431	0.3812	0.2716	0.2119	0.063

1968	3.412		1.608		0.6143	0.3001	0.2309	0.07346

1969	3.211		1.57		0.5946	0.3667	0.2779	0.0824

1970	2.937		1.317		0.6014	0.3466	0.2494	0.07206

1971	1.855		0.9675	0.4636	0.323		0.2495	0.0745

1972	2.971		1.419		0.6904	0.3872	0.2837	0.08212

1973	2.265		1.054		0.4831	0.3214	0.235		0.06792

1974	1.949		0.9601	0.3797	0.2457	0.1932	0.05781

1975	5.266		3.391		1.008		0.4438	0.32		0.08925

1976	1.786		0.7545	0.2605	0.1168	0.1261	0.04423

1977	1.448		0.6314	0.2886	0.2049	0.1745	0.05664

1978	5.485		2.272		0.6986	0.3195	0.2252	0.06654

1979	3.411		1.432		0.6556	0.3246	0.2565	0.07655

1980	1.348		0.5586	0.2685	0.1511	0.1383	0.04554

1981	2.625		1.114		0.5066	0.3323	0.2575	0.07694

1982	0.8976	0.3848	0.2617	0.1604	0.1161	0.04308

1983	0.6274	0.3517	0.2599	0.1095	0.07946	0.03825

1984	5.433		2.728		1.104		0.5139	0.3621	0.1022

1985	4.779		2.035		0.6108	0.3809	0.2769	0.07982

1986	1.824		0.9156	0.4323	0.342		0.2514	0.07123

1987	2.371		0.9961	0.371		0.1901	0.1816	0.0567

1988	1.435		0.6042	0.3041	0.1963	0.1802	0.05817

1989	2.823		1.287		0.5291	0.3507	0.2616	0.07916

1990	0.8369	0.4513	0.295		0.1372	0.096		0.04047

Sorted results

Prob.	Peak	96 hr	21 Day	60 Day	90 Day	Yearly

0.1	5.2173	2.2483	0.75188	0.38657	0.28312	0.082372

Average of yearly averages:	0.066252

Inputs generated by pe4.pl - 8-August-2003

Data used for this run:

Output File: CottonNC

Metfile:	w13722.dvf

PRZM scenario:	NCcottonC.txt

EXAMS environment file:	ir298.exv

Chemical Name:	Cypermethrin

Description	Variable Name	Value	Units	Comments

Molecular weight	mwt	416.3	g/mol

Henry's Law Const.	henry	3.4e-7	atm-m^3/mol

Vapor Pressure	vapr	2.5e-9	torr

Solubility	sol	0.04	mg/L

Kd	Kd		mg/L

Koc	Koc	141700	mg/L

Photolysis half-life	kdp	36.2	days	Half-life

Aerobic Aquatic Metabolism	kbacw	11.3	days	Halfife

Anaerobic Aquatic Metabolism	kbacs	19.3	days	Halfife

Aerobic Soil Metabolism	asm	62	days	Halfife

Hydrolysis:	pH 5	0	days	Half-life

Hydrolysis:	pH 7	0	days	Half-life

Hydrolysis:	pH 9	1.9	days	Half-life

Method:	CAM	2	integer	See PRZM manual

Incorporation Depth:	DEPI	0	cm

Application Rate:	TAPP	0.112	kg/ha

Application Efficiency:	APPEFF	0.95	fraction

Spray Drift	DRFT	0.16	fraction of application rate applied to pond

Application Date	Date	1-7	dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1	interval	3	days	Set to 0 or delete line for single app.

Interval 2	interval	3	days	Set to 0 or delete line for single app.

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

Interval 4	interval	3	days	Set to 0 or delete line for single app.

Interval 5	interval	3	days	Set to 0 or delete line for single app.

Record 17:	FILTRA	

IPSCND	3

UPTKF	

Record 18:	PLVKRT	

PLDKRT	.13

FEXTRC	0.5

Flag for Index Res. Run	IR	IR

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

Write Benthic Porewater File?	benthic	

Write Benthic Sediment File?	benthicsed	

Cotton Texas

stored as CottonTX.out

Chemical: Cypermethrin

PRZM environment: TXcottonC.txt	modified Friday, 6 December 2002 at
08:25:18

EXAMS environment: ir298.exv	modified Thuday, 29 August 2002 at 10:34:12

Metfile: w13958.dvf	modified Wedday, 3 July 2002 at 04:06:24

Water segment concentrations (ppb) 

Year	Peak		96 hr		21 Day	60 Day	90 Day	Yearly

1961	1.577		0.8782	0.4497	0.1831	0.1439	0.03805

1962	1.133		0.4547	0.2521	0.1278	0.09677	0.02687

1963	0.6046	0.3411	0.251		0.09555	0.06487	0.01705

1964	0.6067	0.3434	0.2531	0.09779	0.0755	0.02353

1965	0.6073	0.3442	0.2536	0.0995	0.07863	0.02501

1966	0.6066	0.3434	0.2529	0.1351	0.09717	0.026

1967	0.6067	0.3435	0.2537	0.1036	0.08379	0.02615

1968	1.039		0.5805	0.3312	0.1303	0.09437	0.02719

1969	0.6044	0.3408	0.2509	0.126		0.08919	0.02477

1970	0.6084	0.3454	0.2546	0.09779	0.07011	0.02002

1971	0.8563	0.427		0.2516	0.1392	0.09671	0.02576

1972	0.6115	0.349		0.2642	0.1044	0.07122	0.02036

1973	0.9996	0.5834	0.3205	0.1256	0.1002	0.03466

1974	1.198		0.5005	0.254		0.1549	0.1141	0.03354

1975	0.6942	0.4443	0.2827	0.116		0.08549	0.02562

1976	0.7866	0.4442	0.3059	0.1208	0.09663	0.02871

1977	0.6061	0.3428	0.2524	0.09641	0.06923	0.01932

1978	0.6041	0.3405	0.2506	0.1138	0.08269	0.02342

1979	2.672		1.104		0.5084	0.2583	0.179		0.04727

1980	0.6012	0.3371	0.2478	0.09418	0.06786	0.01897

1981	0.6692	0.4145	0.2779	0.1068	0.0844	0.02623

1982	0.6038	0.3401	0.2503	0.09516	0.06434	0.01757

1983	1.098		0.4808	0.3043	0.1247	0.08769	0.02373

1984	0.6059	0.3425	0.2522	0.09644	0.06549	0.02177

1985	0.6443	0.3542	0.2625	0.1009	0.07352	0.02417

1986	0.6045	0.341		0.251		0.09583	0.07742	0.02613

1987	0.8617	0.3565	0.2732	0.1097	0.09496	0.02722

1988	0.6083	0.3458	0.2547	0.09938	0.06712	0.0176

1989	0.6061	0.3428	0.2525	0.1035	0.07118	0.01902

1990	0.8209	0.4617	0.2883	0.113		0.07683	0.02324

Sorted results

Prob.	Peak	96 hr	21 Day	60 Day	90 Day	Yearly

0.1	1.1915	0.58311	0.33013	0.15333	0.11271	0.034548

Average of yearly averages:	0.0252983333333333

Inputs generated by pe4.pl - 8-August-2003

Data used for this run:

Output File: CottonTX

Metfile:	w13958.dvf

PRZM scenario:	TXcottonC.txt

EXAMS environment file:	ir298.exv

Chemical Name:	Cypermethrin

Description	Variable Name	Value	Units	Comments

Molecular weight	mwt	416.3	g/mol

Henry's Law Const.	henry	3.4e-7	atm-m^3/mol

Vapor Pressure	vapr	2.5e-9	torr

Solubility	sol	0.04	mg/L

Kd	Kd		mg/L

Koc	Koc	141700	mg/L

Photolysis half-life	kdp	36.2	days	Half-life

Aerobic Aquatic Metabolism	kbacw	11.3	days	Halfife

Anaerobic Aquatic Metabolism	kbacs	19.3	days	Halfife

Aerobic Soil Metabolism	asm	62	days	Halfife

Hydrolysis:	pH 5	0	days	Half-life

Hydrolysis:	pH 7	0	days	Half-life

Hydrolysis:	pH 9	1.9	days	Half-life

Method:	CAM	2	integer	See PRZM manual

Incorporation Depth:	DEPI	0	cm

Application Rate:	TAPP	0.112	kg/ha

Application Efficiency:	APPEFF	0.95	fraction

Spray Drift	DRFT	0.16	fraction of application rate applied to pond

Application Date	Date	1-7	dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1	interval	3	days	Set to 0 or delete line for single app.

Interval 2	interval	3	days	Set to 0 or delete line for single app.

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

Interval 4	interval	3	days	Set to 0 or delete line for single app.

Interval 5	interval	3	days	Set to 0 or delete line for single app.

Record 17:	FILTRA	

IPSCND	1

UPTKF	

Record 18:	PLVKRT	

PLDKRT	.13

FEXTRC	0.5

Flag for Index Res. Run	IR	IR

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

Write Benthic Porewater File?	benthic	

Write Benthic Sediment File?	benthicsed	

California Onions

stored as Cypermethrin.out

Chemical: Cypermethrin

PRZM environment: CAonion0C.txt	modified Tueday, 8 June 2004 at
12:01:56

EXAMS environment: ir298.exv	modified Thuday, 29 August 2002 at 15:34:12

Metfile: w23155.dvf	modified Wedday, 3 July 2002 at 09:04:20

Water segment concentrations (ppb)

Year	Peak	96 hr	21 Day	60 Day	90 Day	Yearly

1961	0.5165	0.2212	0.1443	0.08728	0.05929	0.01474

1962	0.5173	0.2224	0.146	0.08886	0.06069	0.0152

1963	0.5178	0.2231	0.1462	0.08936	0.06143	0.01545

1964	0.5175	0.2223	0.1461	0.08905	0.06087	0.01516

1965	0.5181	0.2239	0.1464	0.08958	0.06154	0.01545

1966	0.5158	0.2193	0.1435	0.08722	0.05968	0.01505

1967	0.5175	0.2227	0.1458	0.08897	0.06077	0.01522

1968	0.515	0.219	0.1429	0.08647	0.05872	0.01463

1969	0.5156	0.2197	0.1429	0.08675	0.05911	0.01471

1970	0.5143	0.2166	0.1413	0.08545	0.05797	0.01449

1971	0.5184	0.2244	0.1477	0.0893	0.0608	0.01516

1972	0.5444	0.2289	0.1448	0.08722	0.05937	0.01479

1973	0.513	0.2146	0.1395	0.08411	0.05709	0.01423

1974	0.5145	0.2175	0.1418	0.0858	0.05832	0.01492

1975	0.5145	0.2175	0.1419	0.08583	0.0584	0.01462

1976	0.5144	0.217	0.1413	0.08549	0.05818	0.01447

1977	0.516	0.2202	0.1434	0.08672	0.05883	0.01513

1978	0.515	0.218	0.1424	0.08629	0.0587	0.01495

1979	0.5136	0.2158	0.1405	0.08481	0.05763	0.01432

1980	0.5184	0.2238	0.1471	0.08993	0.0616	0.01532

1981	0.514	0.2171	0.141	0.08507	0.05767	0.01438

1982	0.5145	0.2176	0.1415	0.08574	0.05833	0.01457

1983	0.5171	0.2215	0.1453	0.08861	0.06085	0.01572

1984	0.5164	0.2212	0.1441	0.08772	0.05989	0.01493

1985	0.5156	0.2203	0.1439	0.08719	0.05931	0.01489

1986	0.516	0.2197	0.1439	0.08741	0.05976	0.01495

1987	0.5155	0.2187	0.1431	0.08686	0.05955	0.01523

1988	0.5173	0.2216	0.1457	0.08876	0.06053	0.01509

1989	0.5166	0.2205	0.1447	0.08808	0.0602	0.01502

1990	0.5166	0.2208	0.1448	0.08807	0.06007	0.01496

Sorted results

Prob.	Peak	96 hr	21 Day	60 Day	90 Day	Yearly

0.032258064516129	0.5444	0.2289	0.1477	0.08993	0.0616	0.01572

0.0645161290322581	0.5184	0.2244	0.1471	0.08958	0.06154	0.01545

0.0967741935483871	0.5184	0.2239	0.1464	0.08936	0.06143	0.01545

0.129032258064516	0.5181	0.2238	0.1462	0.0893	0.06087	0.01532

0.161290322580645	0.5178	0.2231	0.1461	0.08905	0.06085	0.01523

0.193548387096774	0.5175	0.2227	0.146	0.08897	0.0608	0.01522

0.225806451612903	0.5175	0.2224	0.1458	0.08886	0.06077	0.0152

0.258064516129032	0.5173	0.2223	0.1457	0.08876	0.06069	0.01516

0.290322580645161	0.5173	0.2216	0.1453	0.08861	0.06053	0.01516

0.32258064516129	0.5171	0.2215	0.1448	0.08808	0.0602	0.01513

0.354838709677419	0.5166	0.2212	0.1448	0.08807	0.06007	0.01509

0.387096774193548	0.5166	0.2212	0.1447	0.08772	0.05989	0.01505

0.419354838709677	0.5165	0.2208	0.1443	0.08741	0.05976	0.01502

0.451612903225806	0.5164	0.2205	0.1441	0.08728	0.05968	0.01496

0.483870967741936	0.516	0.2203	0.1439	0.08722	0.05955	0.01495

0.516129032258065	0.516	0.2202	0.1439	0.08722	0.05937	0.01495

0.548387096774194	0.5158	0.2197	0.1435	0.08719	0.05931	0.01493

0.580645161290323	0.5156	0.2197	0.1434	0.08686	0.05929	0.01492

0.612903225806452	0.5156	0.2193	0.1431	0.08675	0.05911	0.01489

0.645161290322581	0.5155	0.219	0.1429	0.08672	0.05883	0.01479

0.67741935483871	0.515	0.2187	0.1429	0.08647	0.05872	0.01474

0.709677419354839	0.515	0.218	0.1424	0.08629	0.0587	0.01471

0.741935483870968	0.5145	0.2176	0.1419	0.08583	0.0584	0.01463

0.774193548387097	0.5145	0.2175	0.1418	0.0858	0.05833	0.01462

0.806451612903226	0.5145	0.2175	0.1415	0.08574	0.05832	0.01457

0.838709677419355	0.5144	0.2171	0.1413	0.08549	0.05818	0.01449

0.870967741935484	0.5143	0.217	0.1413	0.08545	0.05797	0.01447

0.903225806451613	0.514	0.2166	0.141	0.08507	0.05767	0.01438

0.935483870967742	0.5136	0.2158	0.1405	0.08481	0.05763	0.01432

0.967741935483871	0.513	0.2146	0.1395	0.08411	0.05709	0.01423

0.1	0.51837	0.22389	0.14638	0.089354	0.061374	0.015437

Average of yearly averages:	0.014925

Inputs generated by pe4.pl - 8-August-2003

Data used for this run:

Output File: Cypermethrin

Metfile:	w23155.dvf

PRZM scenario:	CAonion0C.txt

EXAMS environment file:	ir298.exv

Chemical Name:	Cypermethrin

Description	Variable Name	Value	Units	Comments

Molecular weight	mwt	416.3	g/mol

Henry's Law Const.	henry	3.4e-7	atm-m^3/mol

Vapor Pressure	vapr	2.5e-9	torr

Solubility	sol	0.040	mg/L

Kd	Kd		mg/L

Koc	Koc	141700	mg/L

Photolysis half-life	kdp	36.2	days	Half-life

Aerobic Aquatic Metabolism	kbacw	11.3	days	Halfife

Anaerobic Aquatic Metabolism	kbacs	19.3	days	Halfife

Aerobic Soil Metabolism	asm	62	days	Halfife

Hydrolysis:	pH 5	0	days	Half-life

Hydrolysis:	pH 7	0	days	Half-life

Hydrolysis:	pH 9	1.9	days	Half-life

Method:	CAM	2	integer	See PRZM manual

Incorporation Depth:	DEPI	0.0	cm

Application Rate:	TAPP	0.112	kg/ha

Application Efficiency:	APPEFF	0.95	fraction

Spray Drift	DRFT	0.16	fraction of application rate applied to pond

Application Date	Date	10-05	dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1	interval	7	days	Set to 0 or delete line for single app.

Interval 2	interval	7	days	Set to 0 or delete line for single app.

Interval 3	interval	7	days	Set to 0 or delete line for single app.

Interval 4	interval	7	days	Set to 0 or delete line for single app.

Record 17:	FILTRA	

IPSCND	1

UPTKF	0

Record 18:	PLVKRT	0

PLDKRT	0.13

FEXTRC	0.5

Flag for Index Res. Run	IR	IR

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

California Lettuce

stored as lettuce_California.out

Chemical: Cypermethrin

PRZM environment: CAlettuceC1.txt	modified Thuday, 17 February 2005 at
15:15:33

EXAMS environment: ir298.exv	modified Thuday, 29 August 2002 at 10:34:12

Metfile: w23273.dvf	modified Wedday, 3 July 2002 at 08:04:22

Water segment concentrations (ppb) 

Year	Peak		96 hr		21 Day	60 Day	90 Day	Yearly

1961	0.527		0.237		0.1567	0.1122	0.0809	0.02578

1962	0.5292	0.24		0.1592	0.1148	0.08369	0.0327

1963	0.5276	0.2367	0.1575	0.113		0.08325	0.02755

1964	0.5292	0.2398	0.1593	0.1146	0.08867	0.03054

1965	0.5456	0.2472	0.1588	0.1143	0.08266	0.03201

1966	0.5291	0.2394	0.1593	0.1146	0.08291	0.03206

1967	0.5293	0.2394	0.1594	0.1147	0.08298	0.0318

1968	0.5279	0.2379	0.1578	0.1133	0.09006	0.02681

1969	0.53		0.2406	0.1601	0.1155	0.08383	0.03498

1970	0.5298	0.2402	0.16		0.1152	0.08366	0.03189

1971	0.529		0.2393	0.159		0.1144	0.08307	0.02759

1972	0.5286	0.2391	0.1586	0.114		0.08388	0.03002

1973	0.5301	0.2406	0.1603	0.1156	0.08391	0.0385

1974	0.7126	0.3176	0.16		0.1154	0.08593	0.04074

1975	0.5298	0.2405	0.1599	0.1153	0.08394	0.03005

1976	0.7596	0.3508	0.1932	0.1564	0.1256	0.039

1977	0.5282	0.2382	0.1581	0.1137	0.08211	0.02933

1978	1.148		0.6764	0.2604	0.1586	0.1181	0.04938

1979	0.5287	0.2382	0.1588	0.1144	0.08294	0.02996

1980	0.5284	0.2385	0.1583	0.1139	0.08233	0.03276

1981	0.528		0.2379	0.1578	0.1135	0.08285	0.03021

1982	0.5276	0.2368	0.1574	0.113		0.08169	0.02908

1983	0.5244	0.2317	0.1534	0.1098	0.08225	0.03662

1984	0.524		0.2308	0.153		0.1092	0.07765	0.0257

1985	0.5272	0.2368	0.157		0.1126	0.08133	0.02821

1986	0.5285	0.239		0.1584	0.1175	0.08587	0.02933

1987	0.5282	0.2384	0.1581	0.1137	0.0839	0.03015

1988	0.5276	0.238		0.1573	0.1131	0.08173	0.02862

1989	0.5284	0.2387	0.1583	0.114		0.08255	0.02523

1990	0.5265	0.2362	0.1561	0.1122	0.08074	0.02415

Sorted results

Prob.	Peak	96 hr	21 Day	60 Day	90 Day	Yearly

0.1	0.6959	0.31056	0.16028	0.11731	0.089921	0.03895

Average of yearly averages:	0.0313583333333333

Inputs generated by pe4.pl - 8-August-2003

Data used for this run:

Output File: lettuce_California

Metfile:	w23273.dvf

PRZM scenario:	CAlettuceC1.txt

EXAMS environment file:	ir298.exv

Chemical Name:	Cypermethrin

Description	Variable Name	Value	Units	Comments

Molecular weight	mwt	416.3	g/mol

Henry's Law Const.	henry	3.4e-7	atm-m^3/mol

Vapor Pressure	vapr	2.5e-9	torr

Solubility	sol	0.04	mg/L

Kd	Kd		mg/L

Koc	Koc	141700	mg/L

Photolysis half-life	kdp	36.2	days	Half-life

Aerobic Aquatic Metabolism	kbacw	11.3	days	Halfife

Anaerobic Aquatic Metabolism	kbacs	19.3	days	Halfife

Aerobic Soil Metabolism	asm	62	days	Halfife

Hydrolysis:	pH 5	0	days	Half-life

Hydrolysis:	pH 7	0	days	Half-life

Hydrolysis:	pH 9	1.9	days	Half-life

Method:	CAM	2	integer	See PRZM manual

Incorporation Depth:	DEPI	0	cm

Application Rate:	TAPP	0.112	kg/ha

Application Efficiency:	APPEFF	0.95	fraction

Spray Drift	DRFT	0.16	fraction of application rate applied to pond

Application Date	Date	1-8	dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1	interval	7	days	Set to 0 or delete line for single app.

Interval 2	interval	7	days	Set to 0 or delete line for single app.

Interval 3	interval	7	days	Set to 0 or delete line for single app.

Interval 4	interval	7	days	Set to 0 or delete line for single app.

Interval 5	interval	7	days	Set to 0 or delete line for single app.

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Record 17:	FILTRA	

IPSCND	1

UPTKF	

Record 18:	PLVKRT	

PLDKRT	0.13					

FEXTRC	0.5

Flag for Index Res. Run	IR	IR

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

Write Benthic Porewater File?	benthic	0

Write Benthic Sediment File?	benthicsed	0

( PAGE  10 (