ASTM E2686-09(2015)

Standard Test Method for Volatile Organic Compound (VOC) Solvents Absorbed/Adsorbed By Simulated Soil Impacted by Pesticide Emulsifiable Concentrate (EC) Applications

SIGNIFICANCE AND USE
5.1 This test method is designed specifically for emulsions of pesticide emulsifiable concentrates.  
5.2 This test method provides information on the absorption/adsorption of solvents by simulated organic soil and inorganic soil impacted by pesticide EC emulsion applications.  
5.3 The amount of solvent lost by volatilization at 40ºC as determined by this method is an indirect measure of the atmospheric availability of the solvent to potentially react with nitrogen oxides to form tropospheric ozone, a major air pollutant.
SCOPE
1.1 This test method simulates the application of an emulsion of a pesticide emulsifiable concentrate (EC) to soil with high organic matter (corn cob granules) and to soil with high inorganic matter (clay granules) and determines the amount of solvent retained by the granules, and withheld from the atmosphere, before and after exposure to 40ºC in a vented oven. The granules simulate two extremes of soil composition, and the 40ºC exposure simulates high temperature weathering. Solvent loss from organic substrates other than corn cob may also be determined by repeating the 40°C exposure tests with the chosen substrate replacing corn cob. The results with corn cob, however, are a reference that must be reported with the alternate substrate results. The difference in solvent content of the granules before and after weathering is an indication of the emission of the solvent from soil impacted by emulsions or solutions during pesticide applications using common practices such as spraying and drip irrigating. Analysis of the granules for solvent content is by high pressure liquid chromatography (HPLC), gas chromatography (GC), or other methods tested and proven to be accurate and reproducible.
Note 1: Since it evaluates soil surface sorption, this test method will underestimate soil sorption from pesticide applications made below the soil surface. Sub-soil surface treatments may include, but are not limited to, mechanical soil injection and soil incorporation applications. In these cases, the increased depth of the sub-soil treatments reduce the soil surface exposure and facilitate increased levels of soil sorption.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 30-Sep-2015
• ICS: 13.080.10 - Chemical characteristics of soils
• Technical Committee: E35 - Pesticides, Antimicrobials, and Alternative Control Agents
• Drafting Committee: E35.22 - Pesticide Formulations and Delivery Systems

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:E2686 −09 (Reapproved 2015)
Standard Test Method for
Volatile Organic Compound (VOC) Solvents Absorbed/
Adsorbed By Simulated Soil Impacted by Pesticide
Emulsifiable Concentrate (EC) Applications
This standard is issued under the fixed designation E2686; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
1.1 This test method simulates the application of an emul-
sion of a pesticide emulsifiable concentrate (EC) to soil with
2. Referenced Documents
high organic matter (corn cob granules) and to soil with high
inorganic matter (clay granules) and determines the amount of
2.1 Other Standards:
solvent retained by the granules, and withheld from the
40 CFR 51.100(s) Protection of Environment—
atmosphere, before and after exposure to 40ºC in a vented
Requirements for Preparation,Adoption, and Submittal of
oven.The granules simulate two extremes of soil composition,
Implentation Plans—Definitions
and the 40ºC exposure simulates high temperature weathering.
Solvent loss from organic substrates other than corn cob may
3. Terminology
also be determined by repeating the 40°C exposure tests with
3.1 Definitions:
the chosen substrate replacing corn cob. The results with corn
3.1.1 absorb, v—a process in which one material (the
cob, however, are a reference that must be reported with the
absorbent) takes in, and retains, through its pores and inter-
alternate substrate results. The difference in solvent content of
stices the molecules of another material (the absorbate).
the granules before and after weathering is an indication of the
3.1.2 adsorb, v—a process in which one material (the
emission of the solvent from soil impacted by emulsions or
adsorbent) attracts to, and retains on, its surface the molecules
solutionsduringpesticideapplicationsusingcommonpractices
of another material (the adsorbate).
such as spraying and drip irrigating. Analysis of the granules
for solvent content is by high pressure liquid chromatography 3.1.3 emulsifiable concentrate, n—asingle-phaseliquidsys-
(HPLC), gas chromatography (GC), or other methods tested tem having the property of forming an emulsion when mixed
and proven to be accurate and reproducible. with water.
NOTE 1—Since it evaluates soil surface sorption, this test method will
3.1.4 emulsifying agent, n—a surfactant that promotes the
underestimate soil sorption from pesticide applications made below the
suspension of one liquid in another.
soil surface. Sub-soil surface treatments may include, but are not limited
to, mechanical soil injection and soil incorporation applications. In these 3.1.5 gas or liquid chromatography, n—a process in which
cases,theincreaseddepthofthesub-soiltreatmentsreducethesoilsurface
a chemical mixture carried by a mobile liquid or gas is
exposure and facilitate increased levels of soil sorption.
separated into components as a result of different affinities of
1.2 The values stated in SI units are to be regarded as thecomponentsfortheliquidorgasandtheadsorbingmedium
standard. No other units of measurement are included in this through which they pass.
standard.
3.1.6 inorganic matter, n—substances of mineral origin that
are not characterized by primarily carbon-based structures.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3.1.7 organic matter, n—in soil, organic matter consists of
responsibility of the user of this standard to establish appro-
plant and animal material that is in the process of decompos-
ing.
3.1.8 tropospheric ozone, n—an air pollutant formed by the
sunlightcatalyzedreactionbetweenhydrocarbonsandnitrogen
This test method is under the jurisdiction of ASTM Committee E35 on
Pesticides, Antimicrobials, and Alternative Control Agents and is the direct
responsibility of Subcommittee E35.22 on Pesticide Formulations and Delivery
Systems.
Current edition approved Oct. 1, 2015. Published November 2015. Originally AvailablefromU.S.GovernmentPrintingOfficeSuperintendentofDocuments,
approved in 2009. Last previous edition approved in 2009 as E2686–09. DOI: 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
10.1520/E2686-09R15. www.access.gpo.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2686−09 (2015)
oxides present in the troposphere, the layer of the atmosphere 6.3 Glass bottle or jar,round,withscrew-threadcap,foruse
closest to the earth’s surface. with roller system. Typical size is 1 to 4 L.
3.1.9 volatile organic compound (VOC), n—anycompound
6.4 Oven, vented, mechanical convection, 40 6 2ºC, 2.0 ft
of carbon, excluding carbon monoxide, carbon dioxide, car-
minimum inside capacity, 50 to 90 air exchanges per hour.
bonic acid, metallic carbides or carbonates, and ammonium
6.5 125-mL laboratory media bottles, glass, round, outside
carbonate, which participates in atmospheric photochemical
diameter about 55 mm, height about 123 mm, inside diameter
reactions; excluded is a list of organic compounds which have
opening about 30 mm, with screw-thread caps.An example is
been determined to have negligible photochemical reactivity
Wheaton brand, available from many laboratory supply com-
(40 CFR 51.100(s)).
panies.
3.1.10 volatilize, v—to pass off as vapor; to evaporate.
6.6 Apparatus required by the analytical test method.
4. Summary of Test Method
7. Reagents and Materials
4.1 A pesticide EC (emulsifiable concentrate) is simulated
with a concentrate consisting only of solvent plus emulsifying
7.1 Corn cob granules, 20/40 Mesh
agent(s). The concentrate is then mixed with water, and the
7.2 Montmorillonite clay granules, LVM, 12/24 Mesh.
emulsion is applied to corn cob granules (organic substrate)
7.3 Solvent to be tested.
andmontmorilloniteclaygranules(inorganicsubstrate),which
absorb/adsorb the liquid.
7.4 Emulsifying agent(s) suitable for emulsifying the sol-
4.2 Other organic substrates, like corn stover, straw, or vent.
sphagnum peat, for example, may simulate the harvest debris
7.5 Reagents and materials required by the analytical test
from some crops better than corn cob, and the test method can
method.
beusedwithanyofthistypesubstratereplacingcorncob.Care
must be taken to select a substrate appropriate for the crop of
8. Hazards
concern,andtheresultswithcorncobareareferencethatmust
8.1 Before testing, read the precautionary statements on
be reported with the alternate substrate results. The treated
product labels and the Material Safety Data Sheets (MSDS).
granules are placed in a vented 40ºC oven in uncapped bottles.
Take proper precautions to prevent skin contact and inhalation
The uncapped bottles allow for loss of the solvent by volatil-
of fumes or dust. Take care to prevent contamination of the
ization. Each bottle is left in the oven for a different, and ever
surrounding area. Always wear the appropriate safety equip-
increasing,timeperiod.Thetimeperiodforthefirstbottlemay
ment and, where indicated, wear respiratory devices approved
be as little as two hours, and that for the last bottle may be as
by the National Institute of Occupational Safety and Health
much as one-hundred twenty hours or longer. After the 40ºC
(NIOSH) for the product being tested.
exposure,thegranulesareanalyzedtodeterminetheamountof
solvent still retained. Successive time periods continue until
8.2 Store, handle, and dispose of test materials with consid-
theamountofsolventfoundintwoormoresuccessivesamples
eration for health and environmental safety, and in accordance
indicates more exposure time is not expected to cause signifi-
with federal, state, and local regulations.
cantlymorelossofsolvent.Analysisisbyhighpressureliquid
chromatography (HPLC), gas chromatography (GC), or other
9. Sampling, Test Specimens, and Test Units
methods tested and proven to give accurate and reproducible
9.1 The uniform mixing of the roller system procedure
results.
ensures any size sample taken from the roller system jar is a
5. Significance and Use
representative sample. Do not use riffling to reduce a gross
sampleofthetreatedgranulestoarepresentative,suitablesize.
5.1 This test method is designed specifically for emulsions
Significant volatilization of the solvent may occur during
of pesticide emulsifiable concentrates.
riffling or any other time the granules are not in a sealed
5.2 This test method provides information on the
container.
absorption/adsorptionofsolventsbysimulatedorganicsoiland
inorganicsoilimpactedbypesticideECemulsionapplications.
10. Preparation of Apparatus
5.3 The amount of solvent lost by volatilization at 40ºC as
10.1 For all apparatus, see the manufacturers’ instructions
determined by this method is an indirect measure of the
for proper operation and maintenance.
atmosphericavailabilityofthesolventtopotentiallyreactwith
nitrogen oxides to form tropospheric ozone, a major air
11. Calibration and Standardization
pollutant.
11.1 See the analytical test method to be used for determin-
6. Apparatus
ing solvent content for information relative to calibration and
adjustment of the apparatus necessary for the use of the
6.1 Balance, sensitivity of 0.01 g.
method.
6.2 Roller System, two or more rollers with a drive bed,
capable of rotating a glass bottle or jar, about 1 to 4 L in size, 11.2 See the analytical test method for the standardization
at 20 to 60 r/min. and use of reference standards and blanks used in the method.
E2686−09 (2015)
12. Procedure of the granules inside. Rotate 10 min. Repeat the increment
additions of emulsion and 10 min rotating two more times.
12.1 Prepare an emulsifiable concentrate consisting only of
solvent plus emulsifying agent(s). A typical formula is 90 to
12.9 Use an analytical method tested and proven to give
92% solvent and 8 to 10% emulsifying agent(s). Check the accurateandreproducibleresults.HPLCandGCmethodshave
emulsion performance by adding 1 part concentrate to 14 parts
been used successfully.
water. Stir the mixture to form the emulsion. The emulsion
12.10 Determinebytrialanderrorthenumberofsuccessive
should form easily, remain free of separation for 15 min, and
time periods needed for tracking the loss of solvent from the
re-emulsifyeasilyaftersitting24h.Iftheconcentratedoesnot
granulesbyvolatilizationat40ºCtoaplateauindicatingfurther
meet these performance limits, reformulate using a different
loss is not expected to be significant. A minimum of five
emulsifyingagent(s).Keeptheconcentrateandtheemulsionin
successive time periods is needed to conclude the plateau
closed containers, regardless of the ambient temperature, to
occurs; two of those periods must be 0 h and 72 h.Tracking is
prevent loss of solvent by volatilization. Open the containers
completed when the results from any two of three successive
only for the time needed to perform a necessary task.
time periods do not differ from each other by more than the
12.2 Analyze the concentrate for weight % solvent, using accuracy of the test method. See 15.2 for repeatability and
the same analytical method to be used for the treated granules.
reproducibility standard deviation and the 95% repeatability
Repeat the analysis. The two analyses must not differ more and reproducibility limits on the difference between test
than 4% from each other. Use the average to calculate the
results.
makeup of the emulsion to be used for treating the granules.
In the rare event it is concluded that a plateau for loss by
vaporization will not be seen, the half-life for biodegradation
12.3 Prepare one batch of emulsion treated corn cob gran-
of the solvent in soil can be used as a second tier end-point.
ules and one batch of emulsion treated clay granules as
Stop the testing after exposure time at 40°C equals 3× the
described below. These are the primary sampling units. Test
biodegradation half-life.The determination of soil biodegrada-
unit samples are sub-units taken from these primary units.
tion half-life, itself, is beyond the scope of this test.
12.4 Keep all treated granules in closed containers, regard-
12.11 A suggested sequence of successive time periods at
less of the ambient temperature, to prevent loss of solvent by
40ºC for starting trial and error tests is: 0 h, 8 h, 24 h, 48 h, 72
volatilization. Open the containers only for the time needed to
h, 96 h, and 120 h.
perform a necessary task.
12.12 A suggested testing protocol is as follows: Prepare
12.5 Typically,thedesiredweight%solventingranulesfor
threesetsofseven125-mLmediabottlescontainingthetreated
analysis by HPLC or GC is about 1%%.Asuggested protocol
granules. Trial and error results may reduce or increase the
for the preparation of granules with 1% solvent is as follows:
number of samples actually needed.
Prepare a concentrate of 90% solvent plus 10% surfactant(s).
Add 1.1 parts concentrate to 14 parts water.Add the resulting
12.13 Weigh the empty bottle and cap to the nearest 0.01 g.
emulsion to 85 parts granules and mix to uniformity. Deter-
Add a test unit (nominal weight) of granules to the bottle.
mine the initial solvent content of the granules by extracting a
Typically,thenominalweightofgranulesforHPLCanalysisis
sample with a suitable analytical solvent followed by analysis
5 g, and the nominal weight for GC analysis is 5 to 20 g. Use
of the extract. The weight of the sample, or test unit, for 40°C
the nominal weight specified by the analytical method for all
exposure and subsequent analysis is the weight determined to
40ºC exposures and solvent extractions.
be nominal for the analytical method.
12.14 Weigh the bottle and granules and cap to the nearest
12.6 Begin preparation of the two batches of treated gran-
0.01 g. Determine the exact weight of the granules to the
ulesbyaddinguntreatedgranulestotheglassbottleorjartobe
nearest 0.01 g.
rotatedontherollersystem.Thegranulesshouldfillone-fourth
12.15 Foreachsetofsevenbottles,labelbottle#1forWt%
to one-half the container for the best mixing by rotation to
Solvent after0h@ 40ºC, label bottle #2, #3, #4, #5, #6, and
occur.
#7forWt%Solventafter8,24,48,72,96,and120h@40ºC,
12.7 Add the emulsion to the granules in three equal
respectively.
increments using enough total emulsion to give good distribu-
12.16 For each set of seven bottles, remove the caps from
tionoftheliquidbutnotenoughtowetthegranulestothepoint
bottles #2 through #7 and place the uncapped bottles in the
of
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E2686 − 09 E2686 − 09 (Reapproved 2015)
Standard Test Method for
Volatile Organic Compound (VOC) Solvents Absorbed/
Adsorbed By Simulated Soil Impacted by Pesticide
Emulsifiable Concentrate (EC) Applications
This standard is issued under the fixed designation E2686; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method simulates the application of an emulsion of a pesticide emulsifiable concentrate (EC) to soil with high
organic matter (corn cob granules) and to soil with high inorganic matter (clay granules) and determines the amount of solvent
retained by the granules, and withheld from the atmosphere, before and after exposure to 40ºC in a vented oven. The granules
simulate two extremes of soil composition, and the 40ºC exposure simulates high temperature weathering. Solvent loss from
organic substrates other than corn cob may also be determined by repeating the 40°C exposure tests with the chosen substrate
replacing corn cob. The results with corn cob, however, are a reference that must be reported with the alternate substrate results.
The difference in solvent content of the granules before and after weathering is an indication of the emission of the solvent from
soil impacted by emulsions or solutions during pesticide applications using common practices such as spraying and drip irrigating.
Analysis of the granules for solvent content is by high pressure liquid chromatography (HPLC), gas chromatography (GC), or other
methods tested and proven to be accurate and reproducible.
NOTE 1—Since it evaluates soil surface sorption, this test method will underestimate soil sorption from pesticide applications made below the soil
surface. Sub-soil surface treatments may include, but are not limited to, mechanical soil injection and soil incorporation applications. In these cases, the
increased depth of the sub-soil treatments reduce the soil surface exposure and facilitate increased levels of soil sorption.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2.1 Other Standards:
40 CFR 51.100(s) Protection of Environment—Requirements for Preparation, Adoption, and Submittal of Implentation
Plans—Definitions
3. Terminology
3.1 Definitions:
3.1.1 absorb, v—a process in which one material (the absorbent) takes in, and retains, through its pores and interstices the
molecules of another material (the absorbate).
3.1.2 adsorb, v—a process in which one material (the adsorbent) attracts to, and retains on, its surface the molecules of another
material (the adsorbate).
3.1.3 emulsifiable concentrate, n—a single-phase liquid system having the property of forming an emulsion when mixed with
water.
3.1.4 emulsifying agent, n—a surfactant that promotes the suspension of one liquid in another.
This test method is under the jurisdiction of ASTM Committee E35 on Pesticides, Antimicrobials, and Alternative Control Agents and is the direct responsibility of
Subcommittee E35.22 on Pesticide Formulations and Delivery Systems.
Current edition approved April 1, 2009Oct. 1, 2015. Published June 2009November 2015. Originally approved in 2009. Last previous edition approved in 2009 as
E2686–09. DOI: 10.1520/E2686-09.10.1520/E2686-09R15.
Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
www.access.gpo.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2686 − 09 (2015)
3.1.5 gas or liquid chromatography, n—a process in which a chemical mixture carried by a mobile liquid or gas is separated
into components as a result of different affinities of the components for the liquid or gas and the adsorbing medium through which
they pass.
3.1.6 inorganic matter, n—substances of mineral origin that are not characterized by primarily carbon-based structures.
3.1.7 organic matter, n—in soil, organic matter consists of plant and animal material that is in the process of decomposing.
3.1.8 tropospheric ozone, n—an air pollutant formed by the sunlight catalyzed reaction between hydrocarbons and nitrogen
oxides present in the troposphere, the layer of the atmosphere closest to the earth’s surface.
3.1.9 volatile organic compound (VOC), n— any compound of carbon, excluding carbon monoxide, carbon dioxide, carbonic
acid, metallic carbides or carbonates, and ammonium carbonate, which participates in atmospheric photochemical reactions;
excluded is a list of organic compounds which have been determined to have negligible photochemical reactivity (40 CFR
51.100(s)).
3.1.10 volatilize, v—to pass off as vapor; to evaporate.
4. Summary of Test Method
4.1 A pesticide EC (emulsifiable concentrate) is simulated with a concentrate consisting only of solvent plus emulsifying
agent(s). The concentrate is then mixed with water, and the emulsion is applied to corn cob granules (organic substrate) and
montmorillonite clay granules (inorganic substrate), which absorb/adsorb the liquid.
4.2 Other organic substrates, like corn stover, straw, or sphagnum peat, for example, may simulate the harvest debris from some
crops better than corn cob, and the test method can be used with any of this type substrate replacing corn cob. Care must be taken
to select a substrate appropriate for the crop of concern, and the results with corn cob are a reference that must be reported with
the alternate substrate results. The treated granules are placed in a vented 40ºC oven in uncapped bottles. The uncapped bottles
allow for loss of the solvent by volatilization. Each bottle is left in the oven for a different, and ever increasing, time period. The
time period for the first bottle may be as little as two hours, and that for the last bottle may be as much as one-hundred twenty
hours or longer. After the 40ºC exposure, the granules are analyzed to determine the amount of solvent still retained. Successive
time periods continue until the amount of solvent found in two or more successive samples indicates more exposure time is not
expected to cause significantly more loss of solvent. Analysis is by high pressure liquid chromatography (HPLC), gas
chromatography (GC), or other methods tested and proven to give accurate and reproducible results.
5. Significance and Use
5.1 This test method is designed specifically for emulsions of pesticide emulsifiable concentrates.
5.2 This test method provides information on the absorption/adsorption of solvents by simulated organic soil and inorganic soil
impacted by pesticide EC emulsion applications.
5.3 The amount of solvent lost by volatilization at 40ºC as determined by this method is an indirect measure of the atmospheric
availability of the solvent to potentially react with nitrogen oxides to form tropospheric ozone, a major air pollutant.
6. Apparatus
6.1 Balance, sensitivity of 0.01 g.
6.2 Roller System, two or more rollers with a drive bed, capable of rotating a glass bottle or jar, about 1 to 4 L in size, at 20
to 60 r/min.
6.3 Glass bottle or jar, round, with screw-thread cap, for use with roller system. Typical size is 1 to 4 L.
6.4 Oven, vented, mechanical convection, 40 6 2ºC, 2.0 ft minimum inside capacity, 50 to 90 air exchanges per hour.
6.5 125-mL laboratory media bottles, glass, round, outside diameter about 55 mm, height about 123 mm, inside diameter
opening about 30 mm, with screw-thread caps. An example is Wheaton brand, available from many laboratory supply companies.
6.6 Apparatus required by the analytical test method.
7. Reagents and Materials
7.1 Corn cob granules, 20/40 Mesh
7.2 Montmorillonite clay granules, LVM, 12/24 Mesh.
7.3 Solvent to be tested.
7.4 Emulsifying agent(s) suitable for emulsifying the solvent.
7.5 Reagents and materials required by the analytical test method.
E2686 − 09 (2015)
8. Hazards
8.1 Before testing, read the precautionary statements on product labels and the Material Safety Data Sheets (MSDS). Take
proper precautions to prevent skin contact and inhalation of fumes or dust. Take care to prevent contamination of the surrounding
area. Always wear the appropriate safety equipment and, where indicated, wear respiratory devices approved by the National
Institute of Occupational Safety and Health (NIOSH) for the product being tested.
8.2 Store, handle, and dispose of test materials with consideration for health and environmental safety, and in accordance with
federal, state, and local regulations.
9. Sampling, Test Specimens, and Test Units
9.1 The uniform mixing of the roller system procedure ensures any size sample taken from the roller system jar is a
representative sample. Do not use riffling to reduce a gross sample of the treated granules to a representative, suitable size.
Significant volatilization of the solvent may occur during riffling or any other time the granules are not in a sealed container.
10. Preparation of Apparatus
10.1 For all apparatus, see the manufacturers’ instructions for proper operation and maintenance.
11. Calibration and Standardization
11.1 See the analytical test method to be used for determining solvent content for information relative to calibration and
adjustment of the apparatus necessary for the use of the method.
11.2 See the analytical test method for the standardization and use of reference standards and blanks used in the method.
12. Procedure
12.1 Prepare an emulsifiable concentrate consisting only of solvent plus emulsifying agent(s). A typical formula is 90 to 92 %
solvent and 8 to 10 % emulsifying agent(s). Check the emulsion performance by adding 1 part concentrate to 14 parts water. Stir
the mixture to form the emulsion. The emulsion should form easily, remain free of separation for 15 min, and re-emulsify easily
after sitting 24 h. If the concentrate does not meet these performance limits, reformulate using a different emulsifying agent(s).
Keep the concentrate and the emulsion in closed containers, regardless of the ambient temperature, to prevent loss of solvent by
volatilization. Open the containers only for the time needed to perform a necessary task.
12.2 Analyze the concentrate for weight % solvent, using the same analytical method to be used for the treated granules. Repeat
the analysis. The two analyses must not differ more than 4 % from each other. Use the average to calculate the makeup of the
emulsion to be used for treating the granules.
12.3 Prepare one batch of emulsion treated corn cob granules and one batch of emulsion treated clay granules as described
below. These are the primary sampling units. Test unit samples are sub-units taken from these primary units.
12.4 Keep all treated granules in closed containers, regardless of the ambient temperature, to prevent loss of solvent by
volatilization. Open the containers only for the time needed to perform a necessary task.
12.5 Typically, the desired weight % solvent in granules for analysis by HPLC or GC is about 1% %. A suggested protocol for
the preparation of granules with 1 % solvent is as follows: Prepare a concentrate of 90 % solvent plus 10 % surfactant(s). Add 1.1
parts concentrate to 14 parts water. Add the resulting emulsion to 85 parts granules and mix to uniformity. Determine the initial
solvent content of the granules by extracting a sample with a suitable analytical solvent followed by analysis of the extract. The
weight of the sample, or test unit, for 40°C exposure and subsequent analysis is the weight determined to be nominal for the
analytical method.
12.6 Begin preparation of the two batches of treated granules by adding untreated granules to the glass bottle or jar to be rotated
on the roller system. The granules should fill one-fourth to one-half the container for the best mixing by rotation to occur.
12.7 Add the emulsion to the granules in three equal increments using enough total emulsion to give good distribution of the
liquid but not enough to wet the granules to the point of significantly changing their flow properties. Use a transfer pipette to add
the emulsion to the inside wall of the container while the container is being tilted and rotated by hand. The goal is to spread the
liquid in a thin film on the wall so that the liquid does not contact the granules in a concentrated area as would happen by just
pouring the liquid on the granules. Concentrating the area where the liquid contacts the granules may cause clumps, which then
require extra mixing care to re-fragment .
12.8 Add the first emulsion increment, promptly cap the container, and place it on the roller system at, typically, 30 to 50 r/min
for a good cascading motion that gives good mixing of the granules inside. Rotate 10 min. Repeat the increment additions of
emulsion and 10 min rotating two more times.
12.9 Use an analytical method tested and proven to give accurate and reproducible results. HPLC and GC methods have been
used successfully.
E2686 − 09 (2015)
12.10 Determine by trial and error the number of successive time periods needed for tracking the loss of solvent from the
granules by volatilization at 40ºC to a plateau indicating further loss is not expected to be significant. A minimum of five successive
time periods is needed to conclude the plateau occurs; two of those periods must be 0 h and 72 h. Tracking is completed when
the results from any two of three successive time periods do not differ from each other by more than the accuracy of the test
method. See 15.2 for repeatability and reproducibility standard deviation and the 95 % repeatability and reproducibility limits on
the difference between test results.
In the rare event it is concluded that a plateau for loss by vaporization will not be seen, the half-life for biodegradation of the
solvent in soil can be used as a second
...