NEIC
i
PESTICIDE USE OBSERVATION
ADEL, IOWA
August 1981
November 1981
vvEPA
national enforcement investigations center
denver federal center bldg 53, box 25227 denver, co 80225
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF ENFORCEMENT
PESTICIDE USE OBSERVATION
ADEL, IOWA
August 1981
November 1981
Bruce A. Binkley
NATIONAL ENFORCEMENT INVESTIGATIONS CENTER
Denver, Colorado
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CONTENTS
EXECUTIVE SUMMARY
INTRODUCTION
SUMMARY OF INVESTIGATION
CONCLUSIONS
TECHNICAL REPORT
STUDY DESCRIPTION
PESTICIDE STORAGE
MIXING AND LOADING OPERATIONS
APPLICATION
POST APPLICATION
1
2
2
DISCUSSION OF FINDINGS
PESTICIDE STORAGE
MIXING AND LOADING
DRIFT ASSESSMENT
SPRAY PATTERN EVALUATION
EFFICACY OF APPLICATION .
10
10
11
12
23
26
TABLES
1 Station Descriptions
2 Chemical Analysis 2,4-D Residue
3 Droplet Card Counts
4 Comparative Droplet Penetration
FIGURES
7
18
20
27
1 Sampling Devices and Locat ons
2 Label Instructions A1baugh 2 f -D LV-6—D
3 Label Instructions EsteroD 99
4 Label Precautions Albaugh 2,4-D LV-6-D
5 Windspeed and Direction
6 Droplet Image Characterization
. . S I I I I I
4
6
8
8
9
5
13
14
16
21
25
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EXECUTIVE SUMMARY
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INTRODUCTION
At the request of the Environmental Protection Agency, Region VII
office, the National Enforcement Investigations Center (NEIC), in
cooperation with the Iowa Department of Agriculture, conducted a pesti-
cide use observation study in Adel, Iowa, during August 1981. The Iowa
Department of Agriculture through its Pesticide Section operates a
comprehensive certification and enforcement program regulating the use
of agricultural chemicals throughout the state.
A common practice among Iowa growers is the use of aerial applica-
tions of the herbicide 2,4-D to maturing corn crops. The rationale is
that a pre-harvest application of the herbicide will aid in the control
of broadleafed weeds during the following spring growing season. The
corn is often grown in proximity to other broadleaf agricultural crops,
such as soybeans, that are sensitive to the herbicide 2,4-D. The Iowa
Department of Agriculture has in the past received complaints from
growers alleging crop damage to soybeans as a result of aerial appli-
cations of 2,4-D to nearby cornfields.
Through the efforts of a State of Iowa pesticide inspector a test
field was located where corn was being grown adjacent to a sensitive
soybean field. The state solicited the cooperation of the grower and
the aerial applicator scheduled to apply 2-4,D to the corn field to
participate in a use observation study. The objectives of the monitoring
program were to:
• determine if the application of 2,4-D to corn resulted in
pesticide drift into non—target sensitive soybean fields.
• determine users general compliance with pesticide label
instructions and state and federal regulations (FIFRA).*
* Federal Insecticide, Fungicide, and Rodenticide Act as amended
(Public Law 92-516 October 21, 1972, as amended by Public Law
94-140, November 28, 1975 and Public Law 95-396, September 30,
1978).
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2
SUMMARY OF THE INVESTIGATION
On August 25, 1981, NEIC and Iowa inspectors conducted a pesticide
use investigation at Adel, Iowa. A 27-acre corn field was treated with
the herbicide 2,4-D as a pre-harvest control for broadleaf weeds. The
target field was bordered on the south by sensitive soybeans. Twelve
sampling stations were established on and surrounding the target field
for the measurement of herbicide drift. In addition, pesticide storage,
mixing and loading practices were evaluated.
CONCLUSIONS
As a result of the pesticide use observation conducted in Adel,
Iowa on 25 August 1981 by the NEIC in cooperation with the State of Iowa
Department of Agriculture, the following conclusions were reached:
Despite jiearly ideal meterological conditions and obvious
concern and care exercised by the applicator, some of the
herbicide 2,4-D ester drifted from the target corn field into
an adjacent sensitive soybean field. Drift into sensitive
areas, or more severe drift under less ideal conditions, can
be expected unless adequate buffer zones are established
between the target fields and sensitive areas.
The general operation of Campbell, Inc., aerial applicator,
was found to be acceptable. The applicator was knowledgeable
of the potential problems associated with aerial application.
Equipment and working areas were well maintained, clean and
orderly. Mixing and loading, storage and disposal operations
observed were performed in an efficient and safe manner.
An apparent inconsistency with label instructions was noted.
The label instruction for the 2,4-D product applied specifies
1/3 pint per acre, whereas this application consisted of
approximately 1 1/3 pints per acre. This is a violation of
FIFRA, as amnended, Section 12a(2)(G) which states it is
unlawful “to use any registered pesticide in a manner in-
consistent with its labeling.”
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ObservatThns of t ie target corn field by EPA and State of Iowa
Inspectors suggests that this application was unwarranted and
of little economic benefit to the grower. The major portion
of the weed growth observed was wild grass, which is not
susceptible to control by 2,4-D.
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TECHNICAL REPORT
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4
STUDY DESCRIPTION
On August 24, 1981 EPA and State of Iowa inspectors met with the
aerial applicator, Mr. Dean Campbell of Campbell, Inc. and discussed the
use observation study. Mr. C ’ 11 indicated the application of 2 4-D
ester for weed control in the corn field was scheduled for approximately
0800 on August 25, 1981. It was learned that the grower of the corn
field also maintained a soybean field directly south of the target
field. Mr. Campbell indicated he was aware that the soybean field was a
sensitive area. The intended sampling locations and locations of
accessory equipment were explained to Mr. Campbell and he agreed they
would not interfere with his normal application of the 2,4-D ester.
Since some sampling equipment would be located on airport property and
secondary runways, permission was given by Mr. Campbell for such dis-
tribution. Permission to enter on the target and surrounding fields was
granted to a State Inspector by the grower’s family.
The test field suggested by State of Iowa personnel was located at
Adel, Iowa. On 24 August 1981 EPA and state inspectors visited the test
site and found it to be satisfactory for conducting a use observation
study. The test field was cultivated with maturing corn and was scheduled
to be treated with 2,4-D for broadleaved weed control. The target corn-
field encompassed approximately 27 acres and was generally rectangular
in shape (Figure 1). The field was bordered almost entirely to the
south by a sensitive field of maturing soybeans. Non-sensitive corn and
hay fields bordered the target field to the north and east respectively.
The entire western edge of the target field was bordered by the airstrip
and various hangar facilities associated with the Adel Airport. Campbell,
Inc., the aerial applicator responsible for treating the target field,
maintains hangar space and a mixing and loading operation at the Adel
Airport.
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5
0
®AIRSTRIP
FIGURE 1
SAMPLING DEVICES AND LOCATIONS
ADEL, IOWA
25 August 1981
HANGER SPACE
MIXING & LOADING AREA
0
CORN FIE ( •)
— — —
0 01
* * . ARGET FIELD j
I CORN .1
• 1
•1
I I
SOYBEAN FIELD I
542 I
*‘- *-— — --I
I
I I*•
- 1 I
I
I
_ I • I
______ I I.
________ I I
__ _J_I •.
______ •;I•• •‘ ‘• • 1
________ (ii 1 . . I
I a • —
HAY ___________ ________
* FIELD MEASUREMENTS _______________________
INFEET _____________ FIELD
N
0. Spr iy ara Liuster
High Volume Air
* Sampler
Sep Pak Ai.r
Sampler
CORN
FIELD
I
I
I
I
I
I
I
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A total of twelve sampling locations were established on and
surrounding the target field to monitor herbicide drift resulting from
the aerial application (Figure 1, Table 1). Air sampling devices were
placed on and surrounding the target field on August 24, 1981. Three
types of air sampling devices were used: paper spray droplet cards,
High Volume Air Samplers, and solid adsorption columns (C-18 SEP. PAKT l).
Specific details concerning these sampling devices are included in the
Appendix. Spray cards were placed at all twelve sampling locations
(Figure 1). At Stations 8 and 9 on the target field spray cards were
placed on platforms elevated approximately 8 feet from the ground to a
level even with the tops of the corn stalks. Four additional spray
cards were placed around the base of each platform at ground level to
determine the penetration of spray droplets through the corn canopy.
High Volume Air Samplers and SEP_PAKT t columns were installed at Stations
1, 2, 7, 10, 11, and 12. Air samples were taken at Station 2 on
August 24 using High Volume and SEP_PAKTM sampling devices to determine
if background levels of 2,4-D existed prior to the aerial application.
A walk-through inspection was made on the target field by EPA and State
of Iowa inspectors to determine the degree of weed infestation that
existed.
Pesticide Storage
The applicator’s facility was inspected to determine if proper
practices were employed in storing on—hand pesticides. At this period
of the growing season, this applicator’s operation is restricted pri-
marily to the use of the herbicide 2,4-0, 2 ethyihexylester. The
herbicide is purchased in bulk quantities and stored in a 500 gallon,
cylindrical, plastic tank located outside near the aircraft hangar. The
product is pumped into the tank through an access port in the top and
removed through a loadout spigot located at the base of the tank. The
loadout spigot was not locked at this time, nor was a locking device
evident. A label affixed to the top of the tank claimed the contents to
be ALBAIJGHR 2,4-D LV-6-D herbicide. No other pesticides were observed
being stored on the property.
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TABLE 1
STATION DESCRIPTIONS
Adel, Iowa
August 1981
Station No. Location
1 Northwest corner of soybean field 50 feet into field
on the diagonal line.
2 Southwest corner of soybean field 30 feet into field
from west border 520 feet south of Station 1.
3 Midway along northwest—southeast airstrip 20 feet
from the target field.
4 North-south airstrip 150 feet south of intersection
with southeast airstrip 20 feet from cornfield
southeast of the target field.
5 20 feet west of the southwest corner of target field.
6 20 feet west of the northwest corner of target field.
7 25 feet from the north border of target field 750 feet
west of northeast corner of field.
8 Target field 100 feet from north border south of
Station 7.
9 Target field 100 feet from east bord r west of
Station 10.
10 Hayfield 50 feet east of the eastern edge of target
field 278 feet south of the northeast corner.
11 Northeast corner of soybeans field 50 feet into field
on the diagonal line.
12 Soybean field: 90 feet into field from the north edge
680 feet west of the northeast corner.
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Mixing and Loading Operations
The mixing and loading operation used by this applicator was
essentially a closed system. The formulated herbicide is pumped from
the bulk container into a 600 gallon tank trailer which also serves as a
“nurse-rig” when airstrips other than the Adel facility are used. Water
is added to the tank and mixing is accomplished by a recirculating pump
system. Large quantities of herbicide are mixed at one time and the
“nurse-rig” used to service multiple loadings. At the time of the
inspection, sufficient diluted herbicide was available in the “nurse-
rig” to accomplish this application so no actual mixing operation was
observed.
Loading of the aircraft was accomplished by pumping the diluted
material from the “nurse-rig” through heavy gauge hose coupled into the
aircraft. It was noted that when the delivery hose was disconnected
from the aircraft, a plastic pail was held under the hose coupling to
prevent spillage onto the ground. After the mixture was loaded, 8 oz.
of a detergent was added to the spray hopper to act as a surfactant.
An official sample of the herbicide formulation was taken by a
state inspector (Appendix). Because mixing of the herbicide solution
and detergent on board the aircraft was dependent on wind driven vane
pump, the use dilution sample was taken after the application from
material remaining in the spray tank.
Application
The aircraft used for this application was a Piper Pawanee, FAA
registration number N7181Z. The aircraft appeared well-maintained and
exceptionally clean. The spray boom was equipped with 26 DELAVAN foam
nozzles (DF 3_800) directed back into the airstream. Mr. Campbell
stated this configuration provided a 45 foot spray swath when operated
at 40 pounds boom pressure. It was observed that the spray nozzles were
removed from the boom, cleaned and inspected prior to the loading of the
aircraft.
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Because of deteriorating weather conditions the 0800 application
was cancelled by Mr. Campbell. The weather conditions improved sufficiently
by 1300 hr to permit rescheduling the application for 1500 hrs on August 25,
1981. At approximately 1500 hr, filters were placed in the NEIC sampling
devices and spray card clusters installed at all sampling stations.
Electrically operated devices were turned on at this time. The appli-
cation began at 1520 hr when the pilot, Mr. Dean Campbell circled the
field to make last-minute visual observations. The major portion of the
application consisted of passes being made from east to west and west to
east along the long axis of the field. Additional passes were made
along the north-south axis as required to trim the ends of the field.
The aircraft appeared to fly at an altitude of approximately 10-12 feet.
The pilot used both an auto-flagging device and a ground flagger to
maintain position. The ground flagger drove a pickup truck ahead of the
aircraft from north to south along the west perimeter of the target
field. The truck was equipped with a marker flag which allowed the
pilot to observe wind movement at ground level. It was observed that
the spray boom was turned off before leaving and on after entering the
target field. A single load was sufficient to complete the application,
and the treatment was finished by 1537 hrs. Meteorological conditions
monitored during the application showed a ground temperature of 84°F,
relative humidity of 62% and a southeasterly (123°—165°) wind gusting
from 1-3 knots (1.2-3.4 mph).
Post Application
Spray droplet cards were retrieved immediately following the
application. Each card was wrapped separately in aluminum foil, sealed
in a plastic bag and returned to IIEIC for analysis. High-volume air
samplers were allowed to run for approximately 30 minutes after completion
of spraying. Filters were then removed, folded inward and placed in
paper envelopes. SEP_PAKTM cartridges were exposed for approximately
four hours after the application. The cartridges were then removed,
placed in the original foil packet and sealed in plastic bags.
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Clean-up and disposal practices which are normally monitored were
not observed during this study. The applicator was applying only 2,4-D,
2 ethyihexylester at this time, making it unnecessary to rinse and flush
the spray system between applications. Disposal of pesticide containers
was not observed since the herbicide was purchased and stored in bulk
quantities.
DISCUSSION OF FINDINGS
General Overview
Campbell, Inc. conducted an efficient and professional applicating
operation. Aircraft and other equipment were well-maintained, clean and
stored in an orderly manner. The applicator was conscientious, as
indicated by his cleaning and visually inspecting each spray nozzle
before the application. When weather conditions deteriorated, the
applicator cancelled the treatment. The applicator was knowledgeable of
the potential problems associated with 2,4-D into sensitive broadleaved
crops and made the application under weather conditions that specifically
favored drift away from the adjacent soybean field.
The application of 2,4-D ester to the target field occurred without
incident and appeared in all respects to be a routine application. The
use of a ground flag to maintain visual contact with ground level wind
direction is a good practice and an effective means of preventing drift
into sensitive areas.
Pesticide Storage
The purchase and storage of bulk pesticides is an excellent practice
and benefits the applicator in several ways. By incorporatin9 the bulk
storage container into a closed mixing system, worker exposure is
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minimized. A very desirable feature of this practice is the elimination
of disposal of used pesticide containers; a problem that plagues many
commercial applicators. Lastly, but of concern to both applicator and
grower, pesticides purchased in bulk quantities are less expensive.
It was noted that the loadout spigot to the bulk container did not
appear to have a locking device. This does not constitute an inconsistency
since this product bears only a caution warning on the label. However,
because of the accessibility of this tank to the general public, it
would be prudent to install a locking device to prevent vandalism or a
spill.
Mixing and Loading
The actual mixing of the herbicide to a use dilution concentration
was not observed. The mixing of large quantities of use diluted material
is a good practice as it minimizes worker contact with the formulated
material and saves time. In addition, this practice allows for a more
accurate dilution since it is easier to meter larger volumes of pesticide
and water. The applicator does need to assure the product active
ingredient is not subject to rapid deterioration when diluted. In this
instance, 2,4-0 ester remained quite stable in the diluted state. The
applicator indicated that the material in the aircraft spray tank was
equivalent to 5.5 gallons 2,4-0 product, 27.5 gallons water and 8 oz.
detergent. Chemical analysis of the use dilution sample showed this
mixture to contain 15.9% (calculated from equivalent of 59.4% 2,4-D
acid) 2,4-D compared to the calculated claim of 17%. This is within
acceptable limits for a use dilution. Chemical analysis of the formu-
lation product (ALBAUGHR 2,4-0 LV-6-D) showed it was also within acceptable
limits of the label claim. The label claim of 89.5% of active ingredient
(2-ethyihexylester of 2,4 dichlorophenoxyacetic acid) was found to be
89.3%.
Inspection of the label attached to the bulk container indicates
this product was used in a manner inconsistent with the label instructions
which constitutes a violation of FIFRA, as amended, Section 12a(2)(G).
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This section of the regulation states it is an unlawful act “to use any
registered pesticide in a manner inconsistent with its labeling.” The
label for ALBAUGHR 2,4-D LV-6-D (EPA Reg. No. 39511-81) does permit the
use of this product on corn (Figure 2). However the label instruction
states 1/3 pint product per acre, whereas this application provided
approximately 1 1/3 pints product per acre. The label instruction is
intended for a ground-rig application during the early growing season
when weeds are small and corn is 4-18 inches tall. No recommendation or
instruction is given for use of this product as a pre-harvest weed
control for corn. This does not constitute an inconsistency since FIFRA
[ Sec. 2(ee)(3)] amended states the term inconsistent shall not include
“employing any method of application not prohibited by the labeling”.
To summarize; the product could lawfully be applied to mature corn by
aerial methods but only at the recommended dose rate of 1/3 pint per
acre. Other formulations of 2,4-D (Dos, Chemical ESTERONR 99 R concen-
trate) are marketed that do recommend product use for pre—harvest weed
control in corn at dose rates similar to those used by this applicator
(Figure 3). However, this product is a different 2,4-D ester and
marketed under a different EPA Registration Number (464-201). Label
instructions are not interchangeable unless they bear the same EPA
Registration Number.
The loading of the herbicide into the aircraft was açcomplished in
an efficient and careful manner. Even though the 2,4-0 product is of
low toxicity, extreme care was taken to prevent dripping or spillage
onto the ground.
Drift Assessment
Pesticide drift can be defined as any particle of pesticide,
regardless of size, that is transported by air currents to any area
other than the intended target field as a result of an aerial or ground
application. Experience has shown that during an aerial application,
assuming the entire target field is treated, some drift off of the
target field is inevitable. The seriousness of drift is a function of
the relative amount of pesticide being translocated and the sensitivity
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DIRECTIONS FOR USE
Add ft. rocoanwoo,dod amount of product to absut otto -half itt. colons, of
woler to be used in spraying Mix welt, then edd rena ming waler and mu
until spray mislure is uniform Agitate thoroughly while spraying to assure
jnitorm emulsion.
Ueit rosette or. obtalood whon opplicotlano are nsado whit. thu plants era
well leafed and actively grOwing
Do Fall-Plentod Wiaoot, Oets, and Iarley—ttso Va to ½ plot of peodoct In
3 to 10 gallons at waler to cover one acre Apply in early spring when
weeds are small end betore crop has reached the boot sta;t
Do Sprla -Ploota4 WInes, Oats, end Boetay—Uet Va plot of product hi
3 to tO gallons of water It cover ene acre Applg alter the lulls tittered
slfle, eacrpt during the boot to dough stage
co NOT fueago or grato treated grate flolde withIn 2 woOe otter teeatwent
wish 2,4-0 D C NOT feed treated straw to livestock
a - -
ond Sargham—tlae ½ p t n t of product in 3 to 10 gallons .f w ler
so cover ate acre when weeds ace in active growth tocal climatic can
floitions determine when treatment should be made Bose trsstts are usually
ottaunrd when weeds are sttsatt and corn is 4 10 is inches tall Do not
apply learn tasseling to dough stage Troat sorghum whyn t to I ) inches
Pall Uso drop norotee when e,thre crop is over tO inches tall
lot pro—emergent. on torn—Ui. 5i/ to 2%S pints of product lii 3 to 10
gallons of waler per acee Use It t 1 higher late CA heavy soils Do not
roe on sandy toils Plant corn as deep as feasible
Do Tort —Depending on typo . 1 woods and stage of growth, uet Va ta 2
pints and enough water to give o.jffic,ent corerayr to one acre on eslub
tithed stands of perennial grasses DO NOT stir on creeping graises such
as bent ficepi for spot spraying Newly seeded lu ll should Aol be treated
until after the second mowing, and ttso towre dosage rate should be cased
Div tongstsod, Pastures, and ten Cenoeat Weed Control—Van ii’i to D 1 3 p Into
of product in cut licient water to give good coverage to one act,, depending
on type of weeds and stage of growth Use only on nlablished stands of
oorenruiol grasses
DO NOT apply to grass front early boot to mIlk stago where teats seed
production is desieed
DO ff01 apply to newly scadS erect or alter heading begnn.
DO NOT trsoo daIry onlmelt oat treated aeeas wIthin tenon dais stow
opplica lion
For AquatIc Woede In fakee, pondo, drelnage dttchoo, and macthea—Vie
1A to 3 pints of peoducl in 30 to tOO gallons . 1 water and apply to one
acre. Applications should be made when leaves air fully deaetcped above
wator line and plantt are actively growing
DO HOT apply to mora thee t/ to th of lalto yr pond In ony otto month,
because cacnsiva decaying of vegetation may de itrlc susgen Isnlrnt of
waIst, halting fish,
Peraanlef ond Olhor Hord-to .Conlrol Weode nay require a repoat opotleotion
On o; . adeosaale control
FIGURE 2
LABEL tISTRUCTIO [ ’1S
ALBAUGH 2,4—D LV-6-D
August 1981
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FIGURE 3
LABEk I MURUCTIOUS
ESTERON 99 CONCENTRATE
August 1981
moisture is sutticient to cause succutent weed growth NOTE’ Do not teed treated straw to
livestock
WEED CONTROL IN CORN’ Use one ot the following three programs Preemergence Apply Ito 2
quarts per acre to soil anylime after planting but before corrn:meri)es Do not use on light sandy
:il Emergence. Apply; pint per acre lust as corn plants are breaking ground Poslemereence
After emergence ol corn, use 14 pint per acre Application ol ¾ 101 pint per acre may be needed br
masirnum control ol someweeds but such rates are more likely to injure the corn It corn is over 8
inches tall, use drop nossles to keep the spray ott the corn foliage as much as possible Do riot
apply horn the tasseling to dough stage Do not use with oil. atrazine or other ad 1 uvants Crop
Injury is more likely to occur if corn is growing rapidly under high temperature and high soil
lilOisiilry conditions To reduce breakage ot stalks trom temporary brittleness caused by 2 4 ’D
6 ‘ 1 reltivat.on br 8 to 10 days alter treatment Do not torage or teed corn todder br 7 days
‘SllC.”ng application NOTE Hybrids vary in response to 2 4-D and some are easily inlured Spray
ir ty varieties known to be tolerant to 2,4-D Contact seed company or your Agricultural
Cvnsriment S:alinn or Fxtencinn Service weed crweiatislc br lhic inli-irmaiicin
I ‘ IARVEST CORN TREATMENT. After the hard dough ordanting stage, apply t to 2 pints per
ecre by air or ground equipment to suppress perennial weeds, decrease weed seed production
and control tall weeds such as bindweed, cocklebur, dogbane. jimsonweed ragweed suntlower,
velvelleat and vines that interlere with harvesting Do not torsge or teed corn todder br 7 days
following soolicalion
CONTROL OF WILD GARLIC IN STUBBLE GRAIN FIELDS’ Following the harvestol small grain or
corn wild garlic often produces new tall growth This should be sprayed with 2 io3 quarts per acre
of ESTU-RON 99 Concentrate This is a usetul practice as one part ol a wild garlic control program
Do not forage tori days following application
WEED CO’ITROL IN SORGNUM (MILO) Apply 14 pint per acre whensorghum m 5 to 15 inches tat l
A higher rate ot 42101 pint per acre may be needed bocontrol some weeds but thechance for crop
injury m likewise increased Do not use with oil Do not treat before the sorghum is 5 inches tall nor
during the boot, flowering or early dough stages It sorghum is taller than 8 inchcs use drop
nozzles lo keep the spray ott the foliage as much as possible Temporary crop in ury may occur
under conditions of high soil moisture and high air temperatures Varieties vary in tolerance to
2 4-D and some hybrids are quite sensitive Spray only varieties known to be tolerant to 2 4-0
Contact seed company or your Agricultural Experiment Station or Estension Service weed
specialists for this information
GRASS SEED CROPS’ Use ito 1½ pints per acre in the amount of water required for uniform
application by air or ground equipment Apply to established stands in spring trom the tiller to
ea,ry boot stage Do not spray in boot stage New spring seedings may be treated with the lower
rate after the grasses hsi e at least five leaves Perennial weed regrowth may be treated in the tall
WEED ANO BRUSH CONTROL IN RANGELAND AND GRASS PASTURES: NOTE Do not grase
dairy animals on treated areas within 7 days alter application Do not use on bent grsss. alfalta,
clover, or other legumes Do not use on newly seeded areas until grass is welt established Do not
use from early boot to milk stage where grass seed production is desired
Bitferweed, Broomweed, Croton Docks, Kochia, Marshelder, Muskshistle and Other Broadleaf
Weeds’ Use 2 quarts of ESTERON 99 Concentrate per acre in the amount of water needed for
uniform application lithe weeds am young and growing actively 1 quart per acre will provide
control of some species Deeprooted perennial weeds may requi’s repeated treatments in the
same year or in subsequent years
Witd Garlic and Wild D&on’Apply2 to3quaits peracre making three applicationb (fall-spring-fall
or apring’fafl’spring) starting tn late tall or early spring
Weed Control In Newly Sprigged Coastal Bermudagress: Apply 1 to 2 quarts per acre pre-
emergence andtor postemergenca
Send Shinnery Oak and Send Sagebrush On the oak, usel quart inS gallons of oil or in 4 gallons
of water plus 1 gallon of oil per acre Apply by aircraft between May 15 end June tS On the
sagebrush, use t quart in 3 gallons of oil per acre end apply by aircraft when foliage is fully
expanded and the brush is acfrvely growing
Big Sagebrush and Rabbilbrush: Use 2 to 3 quarts r r acre in 2 to3 gallons of oil or in 3 to 5
gallons of oil-water emulsion spray For rabbitbrush the 3 quart rate is usually required Brush
shoutd be leafed out and growing actively when treated Retreatment may be needed
Chemise, Mansenita, Buckbruah, Coastal Sega, Coyotebrush and Cart sin Other Chaparral
Species Use2 to 3qaarts per acre in5 tolOgat Ions of water One gallon of fuel oil maybe included
in the spray mixture for added etfecliveness Make applications by aircraft or ground equipment to
obtain unitorm spray coverage For effective control the brush must be fuly leafed out and
growing actively when sprayed Retreatment may be needed
WOODY PLANT CONTROL IN NON-CROP AREAS: To control species suscaptibte to 2 4-0 in
rights-of-wag fencerowa, roadsides, and along drainage ditchbanks, spray brush up 105108 feet
L I afler a;- ng foliage is well developed, using 3 to 4 quarts 01 ESTERON 99 Concentrate in 100
c • of r,ler and wetting all parla of the brush including foliage, stems and bark This may
raqL.’i t.g. o 400 gallons of spray par acre for adequate coverage of solid stand of brush Make
appuication in such away as to prevent driftot the apiayoff the area beinqtreat f Spraying can be
effective at any time up to 3 weeks belore frost as long as soil rnostura is sufficient for active
growth of the brush Control wilt be less effective in midsummer during hot dry weather when soil
moisture is deficient and plants are noi actively growing Oil or wetting agent may be added to the
spray, if needed for increased effectiveness
FDRESTCONIFER RELEASE’Afler northernconifersjack pine, red pine black spruce and white
spruce cease growth and harden of I in late summer e spray of t’rrto 3 quarts of ESTERON 99
Concentrate inS to 25 gallons of water per acre may be applied by air to control certain competing
hardwood species such as alder, aspen, birch, hazel and willow Since this treatment may cause
occasional conifer injury do not use if such injury cannot be tolerated Consult your regional or
extension forester or state herbicide speciefist for recommendations to fit local conditions
WEED CONTROL IN NON-CROP AREAS SUCH AS LAWNS, GOLF COURSES, CEMETERIES,
PARKS, AIRFIELDS, ROADSIDES, VACANT LOTS, DRAINAGE DITCH BANKS’ Appfyl fo3 quarts
01 ESTERON 99 Concentrate per acie in the amount of wafer needed for uniform application
Usually 2 qaarla per acre provides good weed control under average conditions Treal when
weedeere young and growing welt Do not use on golf gre s norondichondreor other bioadleal
herbaceous ground covers Do not useon creeping gressessuch esbant and St Augustine except
fcr spot treating. nor on newly seeded turf until grass is well estabfishad
14
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15
of the area receiving the drift. A sensitive area is largely determined
by the characteristics of the particular pesticide being applied and
will usually be defined on the pesticide label. In the case of this
application the sensitive area was a soybean field directly south of the
target field. The label instructions for the 2,4-D product applied
states: “Do not apply this product to susceptible broad-leaved plants
that are desirable such as cotton, soybeans ...“ (Figure 4).
The physical characteristics of the spray droplets and local
meteorological conditions determine the rate of transport of airborne
spray particles from the target area. The larger the spray droplet, the
less potential it has to drift from the area of intended application.*
Meteorological conditions affecting drift are: wind direction and
velocity, turbulence, relative humidity, air temperature, and atmospheric
stability. Wind velocity and direction are primarily responsible for
lateral transport of particles, whereas turbulence induces verticle
movements. Re1ati ve humidity and temperature determine the rate of
evaporation and thus influence the size of liquid droplets. Atmospheric
stability characterizes the degree of turbulence associated with certain
meteorological conditions. The most stable atmospheric condition is
known as an inversion, which occurs when the overhead layer of air is
warmer than the air at ground level and is characterized by little or no
air velocity. Such a condition is condusive to pesticide drift as small
particles tend to not descend, but rise into the warmer overlying air
mass. To minimize drift, aerial application is most desirable when the
weather conditions provide a cool temperature, a relatively high humidity
and light wind velocity (2-3 mph) away from any sensitive areas.
Meteorological conditions at the time of the application were good
with a ground temperature of 84°F and a relative humidity of 62%. This
condition would limit evaporation of falling droplets minimizing the
formation of fine particles prone to drifting. The wind velocity of
* Environmental Protection Agency, 1975. U.S. EPA Report No. 540/
9-75-025, 240p.
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16
FIGURE 4
LAI3ELRPRECAUTIO;IS
ALBAUGI I 2,4—0 LV-6—D
August 1981
CAUTION
ThIa product n .y cause shin iryitatlon. Avoid inhaling spray
mist Harmful if swallowed Avoid contact with the eyes, skin.
or ctothing Flush eyes with clear water and get prompt medical
attest ion
DO NOT apply this product to susceptible broad.lesvod plants
that are desirable such as cotton, soybeans, tomatoes, grapes.
clover, or samentals (scessive amounts ot this product in the
soil may leiiiporarily inliihil seed germination and all plant
growth _______
Minute quaetites may cause severs Injury by drift. Avoid drift
of spray and use a coarse spray, s hich it lest likely to drift
Although this product contains an ester of low volatility.
sate ii with caution where the spreading of vapors con damage
nearby susceptible plants.
DO NOT contaminate water In Irrigation ditches or water uted
for ‘domestic purposes
gO NOT contaminate wafer used for Irrigation pr domestic per
poses
Users should note that herbicide teeatsnesst ef public wafers
requires a permit from appropriate state agencies in most states
Your Stale Conservation Department or Game and Fish Commission
will aid you in securing a permit if required in your state
DO NOT store this product near fertlilsers, seeds, lnsecticidm, • ,
fungicides DO NOT contaminate teed or foodsrutts
DO NOT use spray equipment contaminated with this product
for any other purpose untms it has been cleaned very carefully
with a suitable chemical cleaner.
If stored below freesing, it may be necessary ts warm to 4O 1
and agitate before using’ This does not aftect the efficiency of
the product
DO NOT reuse empty containers. Destroy by burying in an
isolated place away from netee s.ippties
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17
1-3 mph from the southeast was away from the sensitive soybean field.
Drift from the target field resulting from this application was
detected in some form at all sample stations (Tables 2,3). Chemical
analysis of spray cards showed 2,4-D ester residue at stations 8 and 9
on the upraised platforms on the target field to be 530 and 610 j.ig per
card (125 crTl 2 ). Assuming these two values are representative of the
field coverage the herbicide was applied at an average concentration of
570 .ig per 125 cm 2 area. As would be expected, pesticide drift was
highest at downwind stations 5, 6, and 7 where residues of 110, 250, and
200 i.tg per card respectively were found (Tab1e 2). These residues
represent 19.3, 43.8, and 35.1 percent of the 2,4-D ester found on the
upraised spray cards on the target field (stations 8 and 9). Since
these stations were directly downwind (Figure 5) and only 20 to 25 feet
from the edge of the target field, these seemingly high residue values
are not surprising. Furthermore drift in this direction (northwest) was
away from the soybean field intQ non-sensitive areas. Stations 1 and 11
in the sensitive soybean field also received some pesticide drift.
Herbicide residues at these stations were 33 and 12 g per card res-
pectively, representing 5.8 and 2.1 percent of the residue found on the
field cards (Table 2). A vegetation sample consisting of soybean leaf
material taken from station 1 contained 5 pg/g 2,4-D ester residue. No
2,4-0 ester residue was detected on spray cards at stations 2 and 12,
also located on the soybean field.
Chemical analysis of the air samplers confirmed that small amounts
of 2,4-0 did drift into the soybean field. Both the high-volume and
SEP_PAKTM air samplers captured herbicide residue at stations 1 and 2
(Table 2). Residue captured by the SEP_PAKTr 4 columns at stations 1 and
2 were 9.2 and 2.5 Mg, respectively, as compared to 5.0 and 1.0 pg
captured at these stations by the high-volume air samplers. It may seem
surprising that the SEP_PAKTM columns captured more 2,4—D residue when
in fact the high-volume air samplers filtered approximately S times more
air volume. Three combined factors may be operating to produce this
apparent discrepancy:
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18
TABLE 2
CHEMICAL ANALYSIS 2,4-0 RESIDUE
ADEL, IOWA
August 1981
Station No. Description Date Concentration of
2,4-0 2-ethyl hexyl ester
VEGETATION ( j ig/g)
01 Soybean leaf 8/25/81 5.0
HIGH VOLUME AIR FILTERS (jig/filter)
02 Background Sample 8/24/81 ND*
01 Soybean Field 8/25/81 5.0
02 Soybean Field 8/25/81 1.0
07 8/25/81 480
10 8/25/81 72
11 Soybean Field 8/25/81 ND*
12 Soybean Field 8/25/81 ND*
SEP-PAK CARTRIDGES (jig/set)
02 Background Sample 8/24/81 ND*
01 Soybean Field 8/25/81 9.2
02 Soybean Field 8/25/81 2.5
07 8/25/81 68
10 8/25/81 7.0
11 Soybean Field 8/25/81 ND*
12 Soybean Field 8/25/81 ND*
n v (jig/drift card)
01 Soybean Field 8/25/81 33
02 Soybean Field 8/25/81 ND*
03 8/25/81 1.2
04 8/25/81 ND*
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19
TABLE 2 (Cont.)
CHEMICAL ANALYSIS 2,4-D RESIDUE
August 1981
Station Ho. Description Date Concentration of
2,4-D 2-ethyihexylester
SPRAY DRIFT CARDS (Cont. ) (pg/drift card)
05 8/25/81 110
06 8/25/81 250
07 8/25/81 200
08 Upraised Platform 8/25/81 530
(target field)
08 N.E. Ground Level 8/25/81 84**
08 S.E. Ground Level 8/25/81 340
08 N.W Ground Level 8/25/81 440
08 S.W. Ground Level 8/25/81 330
09 Upraised Platform 8/25/81 610
(target field)
09 N.E. Ground Level 8/25/81 180
09 S.E. Ground Level 8/25/81 310
09 N.W. Ground Level 8/25/81 40**
09 S.W. Ground Level 8/25/81 240
10 8/25/81 26
11 8/25/81 12
12 8/25/81 ND*
* ND = t on detected. Detection limits were 1.0 pg/high volume filter,
1.0 iig/set and 1.0 iig/drift card.
* These values were not used in calculating averages. Cards were
badly blurred indicating some damage had occurred not related to the
application.
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20
Table 3
DROPLET CARD COUNTS
(Linagraph Paper)
Adel, Iowa
25 August 1981
STATION NO. LOCATION CARD COUf IT (150 CM 2 )
1 Soybean Field 15
2 Soybean Field 8
3 Perimeter 1
4 Perimeter 4
5 Perimeter 220
6 Perimeter 229
7 Perimeter 221
8 Target Field Upraised 1545
8 S.E. Target Field Ground 185
8 S.W. Target Field Ground 229
8 N.E. Target Field Ground 60 (fogged card)
8 N.W. Target Field Ground 303
9 Target Field Upraised 862
9 SE. Target Field Ground 352
9 S.W. Target Field Ground 253
9 N.E. Target Field Ground 167
9 N.W. Target Field Ground 36 (fogged card)
10 Perimeter 39
II Soybean Field 12
12 Soybean Field 4
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21
HANGER SPACE
FIGURE
.iIMDSPEED* NLD DIRECTIG 1
ADEL, IOUA
25 August 1981
[ J iLO ING AREA
Ft ELD MEASUREMENTS
IN FEET
(ii) AIRSTRIP
CORN
F I ELD
HAY
F I ELD
Vector equals 1 mph
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22
1) The SEP_PAKTM column is most efficient in collecting aerosol
and very fine (50p or less) sized particles. Since both stations 1 and
2 were essentially up-wind from the application it is most likely that
pesticide residue in this area was primarily in the form of fine and
aerosol-sized particles that are more likely to drift as a result of
wind turbulence than larger particles that impact quickly. The SEP-
PACTM samplers were therefore allowed to operate approximately four
hours after the completion of the application. Pesticide material
remaining airborne for this length of time is most likely to be in the
form of very fine to aerosol-sized particles.
2) The media used in SEP_PAKTM columns captures the herbicide by
absorption. Once the capture of the particle is made the herbicide
remains quite stable and is little effected by subsequent passage of
additional air flow. In other words, the herbicide has a much greater
affinity for the C-18 media than it does for air so that once the 2,4-D
ester is captured it remains stable in the column.
3) The high-volume air samplers (40 CFM) were only operated 30
minutes after the application. This sampler is most efficient in
capturing large liquid droplets which occur during and shortly after an
aerial application. The fiberglass filter used in this sampler does not
have the absorption quality associated with the SEP_PAKTII. Once pesticide
is captured the additional large airflow is conducive to vaporation and
sublimation of the particle from the filter media back into the air
column. For this reason, this sampler may not always be efficient in
capturing and retaining fine or aerosol-sized particles.
It was previously stated that 9.2 ig of 2,4-D ester residue was
captured by the SEP-PAK T 1 sampler at station 1. During the field
activity, it was discovered 30 minutes after the application was complete
that because of a poor electrical connection this sampler had not been
in operation. At this time the sampler was turned on. All large
pesticide particles would have settled from the air column by this time,
which reinforces the hypothesis that the SEP-PAK 1 samplers were capturing
very fine or aerosol-sized particles.
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23
Station 7, directly north and downwind of the target field had the
highest lev& of 2,4-D residue for both high-volume and SEP_PAKTM
samplers at 480 and 68 pg respectively (Table 2 and Figure 5). The
high-volume sampler at station 10, east and somewhat upwind of the
target field captured 72 pg 2,4-0 residue. Because of the upwind
location, and being approximately 50 feet from the target field this
level seems somewhat high. However, a field inspector noted that this
eastern border of the target field contained a large patch of weeds
extending from the edge of the corn field into the adjacent hay field.
It was observed that when treating this section the pilot intentionally
sprayed off the target field over the weed patch. The hay field is not
a sensitive area and the 2,4-0 product is registered for use on pasture-
land, so intentionally spraying off the target field to treat the weed
patch is not inconsistent and probably benefited the grower.
These data indicate that despite nearly ideal nieterological condi-
tions and a conscientious effort on the part of the applicator, some
drift did occur into a sensitive area. This did not occur as a result
of any observed act of carelessness or negligence on the part of the
applicator. The fact that these fields were adjacent with no buffer
zone made it virtually impossible to treat the corn field completely and
not get some drift into the sensitive soybean field. Since both fields
are the property of the same grower, it is likely that even if_’limited
crop damage was sustained to the bordering rows of soybeans it is still
more economical than losing the acreage required to establish an effective
buffer zone. This would obviously not be the case, however, if different
landowners were involved.
Spray Pattern Evaluation
The characteristics of a spray droplet pattern is usually a com-
promise between the pattern most effective in controlling the target
pest and a droplet pattern that minimizes drift. Finer spray droplets
often provide the most effective kill but also promote a greater pro-
bability of drift leaving the target field. For instance, assuming a
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24
wind velocity of 3 mph and a release height of 10 feet (very similar to
the conditions observed during this application) a course spray with
400-micron droplets will drift laterally for about 8.5 feet; a fine
spray with 100 micron droplets will drift approximately 40 feet. Fine
aerosol-sized droplets could be expected to drift 3/4 mile. For herbicidal
effectiveness as well as adequate drift control a droplet pattern of at
least 72 drops/sq. inch (11 drops/cm 2 ) consisting of particles in the
400-800 micron range (spherical diameter) appears to be optimum.* Drop-
lets less than 200 microns should be minimized.
Analysis of the droplet characterization resulting from this
application must be done with some care. The data is based on spray
droplets sized by measurement of the diameter of the droplet impression
on the spray droplet cards. Actual droplet characteristics effecting
particle drift are dependent on the spherical diameter of the liquid
particle. Because of the nature of spray droplet paper, a spherical
droplet when impacting tends to spread and leave a droplet impression
somewhat larger than the droplet itself. The difference between the
diameter of the liquid droplet and the diameter of the visual impression
left on the spray card is known as the spread factor. The calculated
spread factor is a function of the pesticide formulation, the size range
of the droplets, and the physical characteristics of the droplet paper.
If the effect of all these variables is known a conversion (spread)
factor can be calculated allowing estimation of the spherical diameter
of the original liquid droplet. Typical spread factor values generally
range from 1.5 to 3.
Based on droplet impression diameter measurements the following
evaluations were made. Droplet measurements were made and the values
combined from the elevated platform spray cards at stations 8 and 9 on
the target field. These were assumed to represent the average droplet
characteristics for the application at approximately the height of the
corn. The measurements indicate approximately 36% of the spray droplets
were in the range of 400-700 microns with an equal 36% being less than
400 microns (Figure 6). The remaining 28% ranged from 800-2100 microns.
* Behrens, R., 1957. Influence of Various Components on the Effective-
ness of 2,4,5—T Sprays. Weeds 5:183-196.
-------
Stations 8 and 9 Upraised Platforms
QD
II I 2 13 14 15 16 17 I 8 19 110 Iii 112 113 114 uS 121 I
Droplet Image Diameter in 100 ii Units
25
FIGURE 6
DROPLET It•IAGE CHARACTERIZATIOII
ADEL, IOUA
25 Auçju t 1981
Stations 8 and 9 Ground Level
Southeast Cards
14
12
10
8
6
4
2
0
10
- I -
8
6
4
2
0
12
10
8
6
4
2
0
In
4 -J
c i )
0
C D
4-
0
In
c i i
-r
In
4-,
a)
0-
0
4—
0
C l
0
E
2:
4- )
ci)
I—
0.
0
C D
4-
0
In
ci)
0
Stations 8 and 9 Ground Level
Southwest Cards
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26
Considering these values are inflated for lack of a spread factor the
probable spherical diameter of the droplets would be characteristic of a
medium spray pattern (250-400 microns). The average droplet density for
the two stations was calculated to be 52 droplets per sq. inch or 28%
less than 72 droplets per sq. inch needed for maximum effectiveness.
Measurements of droplet diameters on spray cards on the ground
surrounding the upraised platforms demonstrated that the larger droplets
were more successful in penetrating the corn leaf canopy. These larger
droplets would be the ones reaching weed growth close to ground level.
Droplet measurements were made on four ground level cards; two from
station 8 and two from station 9. The combined data showed only 8% of
the droplets were less than 400 microns as compared to the 36% on the
cards exposed at corn top level (Figure 6). In addition, 60% of the
droplets were in the more desirable 400-700 micron range as compared to
36% in this range on the upraised platforms.
The practical advantage of the greater penetration of the larger
droplets can be seen by comparing the percentage of droplets reaching
the ground cards to those impacting the upraised platforms based on the
actual numbers of droplet impressions visible. This comparison indicates
that 22.7% of the herbicide penetrated the corn leaf canopy to ground
level (Table 4). When this same comparison is made using actual 2,4-D
ester residue on the spray cards the data shows 54.8% of the herbicide
was successful in penetrating the corn leaf canopy. The differing per-
centages are explained when considering that siniply doubling the diameter
of a spherical droplet increases its liquid volume by 8 times. These
data indicate the applicator might benefit by using a courser spray
pattern if the height of target weeds is below that of the corn canopy.
Additionally, increasing the droplet size would reduce the potential
drift.
Efficacy of Application
Inspection of the target corn field by EPA and State inspectors
prior to the application did not reveal that any significant broad-
leaved weed infestation existed. While ground level weed growth was
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27
TABLE 4
COMPARATIVE DROPLET PENETRATION
ADEL, IOWA
25 August 1981
STATION NO. DESCRIPTION DROPLET CQUNT % PENETRATION
( 150 cm’ )
08 Upraised Platform 1545
08 S.E. Ground Level 185 12
08 S.11. Ground Level 229 15
08 N.E. Ground Level 60*
08 N.W. Ground Level 303 20
09 Upraised Platform 862
09 S.E. Ground Level 352 41
09 S.W. Ground Level 253 29
09 N.E. Ground Level 167 19
09 N.W. Ground Level 36* 4
AVERAGE PENETRATION 22.7%
STATION NO. DESCRIPTION 2,4-D RESIDUE % PENETRATION
( pg/card )
08 Upraised platform 530
08 S.E. Ground Level 340 64
08 S.W. Ground Level 330 62
08 N.E. Ground Level 84*
08 N.U. Ground Level 440 83
09 Upraised Platform 610
09 S.E. Ground Level 310 51
09 S.W. Ground Level 240 39
09 N.E. Ground Level 180 30
09 .t. 4Q4 .
AVERAGE PENETRATION 54.8%
* These values were not used in calculating averages - cards were badly
blurred indicating some damage had occurred not related to the application.
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28
very evident, the vast majority of those weeds observed were various
types of wild grasses that would not be effected by the application of
2,4-D ester. It is questionable that this application was of signifi-
cant economic benefit to the grower. Closer field inspections should be
made by the grower to determine if such an application is warranted.
Because of sparsity of broad-leaved weed growth, no evaluation of
efficacy was possible.
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29
APPENDIX
SAMPLING AND ANALYTICAL METHODS
Spray Droplet Cards
Three types of sensitive spray droplet papers were used to deter-
mine drift potential and spray droplet characteristics (Kromecote,
Linagraph 480, and Thermofax 209 copy type 640). Because the sensi-
tivity of the papers varies with the chemical characteristics of the
pesticide, clusters were constructed by stapling one of each types of
paper to a one foot square of poster board and exposing the cards as a
single unit. All spray card clusters off the target field were exposed
atop 4 foot horizontally placed plywood platforms to prevent ground
contamination and raise the cards above existing vegetation. Spray
cards at stations 8 and 9 were elevated approximately 8 feet to a height
level with the corn tassels. Each upright platform at stations 8 and 9
was surrounded by four additional spray cards at ground level under the
corn canopy.
All spray droplet counts were made from the linagraph paper cards
as this material produced the best visual image. Except for stations 8
and 9, (upraised platforms), and station 9 S.E. (ground level) droplet
counts represent the entire spray card (150 cm 2 ). Droplé’t counts from
stations 8 and 9 and 9 S.E. were made by counting the droplets in 5
random 4 cm 2 areas and extrapolating the values to 150 cm 2 . Three
randomly selected cards were recounted to determine droplet count
accuracy. All three recounts agreed within 5% of the original droplet
count.
Droplet sizes were estimated by measuring a minimum of 25 droplet
images per card at the widest visible diameter. Measurements were made
with a bii ocu1ar dissecting nhircoscope using a micrometer measuring grid
at 12X.
Prior to the application, spray card clusters were kept in plastic
bags to prevent contamination. Spray cards removed from field stations
-------
30
after the application were wrapped in aluminum foil, sealed in plastic
bags and returned to NEIC for analysis.
Chemical analysis for 2,4-0 residue on spray cards represented in
the text was done on Kromecote paper. This paper produces the least
background interference when chemically extracted.
Thermofax copy paper cards were not used to produce any data used
in this report.
High Volume Air Samplers
Six high-volume air samplers were used to monitor spray drift.
These samplers draw air through a fiberglass filter media by using an
electrically driven blower. The sampling units were powered by portable
generators and 12 volt battery systems. All units were calibrated to
determine air flow using a linear mass flow meter prior to installation
at the study site. Fiberglass filters were kept in the original box
until just prior to the application. An air sample taken at station 2
prior to the application was chemically analyzed and found to be free of
contamination or background 2,4-D residue. Sampling units were turned
on just prior to and allowed to run approximately 30 minutes after the
application. The fiberglass filters were then removed, folded inward
and sealed in paper envelopes until analyzed at the NEIC laboratory.
SEP _ PAKTM Samplers
SEP_PAKTM samplers are solid adsorbent columns using C-lB as the
active capture media. Air is drawn through the SEP_PAKIIl cartridge by
means of a vacuum pump connected to the cartridge by tygon tubing. Four
cartridges are connected in a parallel series using plastic tees. The
use of four cartidges increases the available air flow and all four
units are composited for chemical analysis. All sampling trains were
calibrated to determine air flow using a dry-flow gas meter. Sample
trains were elevated approximately 4 feet above the ground by attaching
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31
them to wooden stakes. SEP_PAKTM cartridges remained in the original
sealed foil packages until their installation on the sampling device
just prior to the application. Sampling trains were operated from just
prior to until approximately 4 hours after completion of the appli-
cation. After sampling the cartridges were replaced in the original
foil packets, sealed in plastic bags, and returned to NEIC for residue
analysis. An air sample taken at station 2 prior to the application was
analyzed and found to be free of contamination or background 2,4-D ester
residue.
Meterological Measurements
Meterological parameters measured include ground temperature,
relative humidity, wind direction and velocity. Temperature measure-
ments were made with a thermocouple thermometer calibrated against an
NBS thermometer. Relative humidity was taken with a hand held sling
phychrometer. Wind speed and direction were measured with a hand held
anemometer aligned to magnetic north. Readings are given in uncorrected
magnetic degrees.
Formulation and Use Dilution Sampling
Formulation and use dilution samples of the herbicide used for the
application were taken by a State of Iowa Pesticide Inspector. The
attached sample collection reports detail the methods used by this
inspector.
Chain of Custody Procedures
Sample chain of custody and document control methods used during
this study are those detailed in the NEIC Policies and Procedures Manual
(EPA-330/9/78/OOl -R).
-------
SAMPLE COLLECTION REPORT 32
PESTICIDE SECTION SAMPLE NUMBER N I A 0 0 4 1
IOWA DEPARTMENT O) AGRICULTURE
HENRY A. WALLACE BUILDING LABORATORY NUMBER
DES MO)N S, IOWA 50319 DATE RECEIVED
E C0.LECTED lNsP C1OR 5 IDENIIFICAIION Hjv J
03—25--SI 1312
PROD ,(T DESCRIPTION (ndme.brantJ .a.I .cluluiaon r Li .1j, r . g.n . ..rvstdut ‘de:iI ’iy.trcj
One/3 oz. glass sample of the tank mix of “ALBAUG}I 2,4—D LV—6D Herbjcjde +
water ÷ detergent”
RIASO’. FO. COLLECTION
Use Nonitor
METHOD OF CO1L CIION . -
One/8 oz. sample taken frora the applicators spray tank located in front the plane
coc ?it on the airplane owned by-Dean Campbell
S-\\ r’L: . EPARATION
Sa lc lerit. “Sample 1IIA—0041, JLC, 8—25—81., James L. Christensen”
O SUBSAMPLES RELATED SAMPILS
173997
:S REQUESTED
2,4—B (Active Ingredient: 2—Ethylhexy]. Ester+ of
2 ,’i—Dichlorophenoxyacetjc Acid) -
COLLECTiON
Name
Address/Phone
SITE
INFORM.\TION
APPLICATOR
I FORM . T:ON
Dean Campbell
Box 66 Adel, Iowa 50003
Phone 515—993-4147
Firm
Dean Campbell LTD
Where Sample Taken:
Applicators spray tank located in front the airplane cockpit owned by
Name Address/Phone
Dean Campbell Box 66
Firm Adel, Iowa
Dean Campbell LTD
Cerrification Number
2067.01
Carat
.
REMA 5: -
Saziple submitted to Bruce Binkley—Aquatic Brologist with EPA Enforcement Denver
Federal Center, Denver, Colorado
Analysis being done by Denver Lab
\OIICE OF I SPEC lION ISSUED IXIRICEIPI FOR SAMPLES ISSUED
\ HERE S9IPPED !DA ‘pw IHOW siiimu .4r\LsIIG . 1o ,s .NA1ur .F.
‘—j . . 2 . - — - - - -‘ — -. - —
[ rLver Lab j 5—25—81 (Devereri I m Christensen
ft.
I (‘ ) C). ,.bu!,on- !I bh.Ir. S nipteR .covd (cpa’
-------
- 33. -
- U.S. ENVIRONMENTAL PROTECTION AGENCY
COLLECTION REPORT .
II. TYPE SAMPLE
u
I
I 2. SAYPL tlO.
i73 9
7
3.
9.
DATE COLLECT 14. PROJ CODE IS. REGION
08—25—8 1 H—4 IN0. 07
D..TE(S) SHIPPED
08—21—81
Is. INSP NO.
I 1312
110. FLAG
I
Ii. REGISTRATION NO.
[ 39511—81—42750
19• ESTAOLISHMEUT
‘i2750—IA—1
NO.
% 1. P DDUCT IDENTIFICATION (IVarn.. Br nd Q.C. SC.stement, Aclivc In edu.pts, Firm 1Vam and Addre otc.J
One/4 oz. glass sample of “ALBAUGIE 2,4—D LV—6D HERBICIDE 2,4—D L0 7 VOLATILE***
ACTIVE INGREDIENTS: 2—Ethyihexyl Ester+ of 2,4—Diehiorophenoxyacetic Acid 89.57a***
EPA Rag. No. 39511_81_42750* * NET CONTENTS: BULK **
L N1JTACThRED FOR ALBAUCH CHEMICAL C0RP \ .TION ANKENY, I0 -1A 50021”
iza. P ODUCER E5TA L1SHMENT
tUbau h Chemical Corporation
b. ST EET ADDRESS (c. CITY . d. STATE le. ZIP CODE
70! S E Creekview Dr. Iowa [ 50021
3 .. S-I PER
Sa- a
b. STREET ADO ESS • C. CITY d. STATE C. ZIP CODE
14a. D .ALE .
Dean Campbell LTD
b. STREET ADDRESS —
Bo: 66 ‘• ‘
C. Ct1 Y
Adel
d. STATE le. ZI CODE
Towa 150003
RECORDS / ND SAMPLE SCNT TO (Spec ,ty loca lion)
a. O IGINAL RECO°O5
Ia. Dapt Agriculture Chemical Lab
b. PRODUCING RFGIO COPY
Kansas City, MO
C. SAMPLE
Iowa Dept Ag
TO •
‘Ia. Dept Agriculture Chemical Lab
C. DATE
1. R/L NO.
D 3 !oi: .t? : 7 Ioua
IS. LOT O COOE P 10 5.
?:IA.
17. A.IQW.T B!FO E SAMPLING
150 c n1ll r
13. DESRI TIOM OF SAMPLE ANC METHOD OF COLLECTION
One 14 oz. sample taken from the loadout spigot on the bulk storage tank located
at the Adel Airport operated by Dean Campbell
19. SAMPLE PREPARE9 IN THE FO ,LOWINGM iNN R _________________________________________
Label ident. ‘Sample 1r173997, JLC, 8—25—81” and placed in an inverted polybag
and sealed with EPA seal ident. “Sample I 173997, 8—25—81, Janes L. Christensen t ’
2 . LATED SAMPLES COLLECTED FROM SAME SHIPMENT OR AT THE SAME PP0OucEPESTAaLISHME , IT
IA— 0041
21. R ASO4 FOR COLLECTION
Use Monitor
22. P.OTICE OF WSDECTION ISSUED x I 23. RECEIPT FOR SAMPLES I5SU D
24. REMAP.
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34
Formulation and Use-Dilution Analyses
The NEIC Pesticide Formulation Laboratory analyzed a formulation
sample and a use dilution sample of 2-ethyihexylester of 2,4 dichloro-
phenoxyacetic acid. The samples were diluted with acetone and analyzed
by gas chromatography using 3% OV -l at 180°C oven with a flame ionization
detector. Samples were also screened for contaminants by thin layer
chromatography for chlorinated hydrocarbons, organophosphates and
carbamates.
Residue Analyses
The vegetation was analyzed by the NEIC Method For Chlorinated
Phenoxy Acid Herbicides in Soil and Vegetation . The high-volume filters
were analyzed by extraction with 2N NaOH and hydrolysis to the acid form
of 2,4-D. The extracts were then methylated and analyzed according to
the vegetation method. In both cases the presence of 2,4-0 was con-
firmed by analysis on two columns of different polarities and the
methylester results were calculated back to the 2-ethyihexylester.
The Sep-Paks were each eluted with 1 ml of methanol which was
combined with the methanol extracts from the other three Sep-Paks in
each set. The combined extracts were then evaporated in the presence of
excess cyclohexane. The cyclohexane was concentrated to 10 ml and
analyzed on an electron-capture gas chromatograph.
The drift cards were extracted with hexane which was then con-
centrated to 10 ml and also analyzed on an electron-capture gas chroma-
tograph. The Sep-Paks and drift cards were analyzed directly as the 2-
ethyl hexyl ester.
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35
Quality Control
The vegetation was analyzed in duplicate, the results were 6.0 pg/g
and 4.1 j.ig/g.
The high-volume filter field blank, #752-02 (8/24/81), showed no
significant interference. High-volume sample 757-07 was analyzed both
as described in the Methodology Section and by direct hexane extraction
of the 2-ethylhexylester similarly to the drift cards; the hexane
extraction gave a result of 580 pg/filter compared to 480 jig/filter for
the stated methodology.
A spike of the Sep-Paks with 10 pg of 2,4—D 2-ethylhexylester gave
76% recovery and both a laboratory and a field blank gave no significant
interferences.
A laboratory blank of a drift card gave no significant interference
and a spike with 10 pg of 2,4-D 2-ethyihexylester yielded 89% recovery.
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