D18.06 - Physical-Chemical Interactions of Soil and Rock

SIGNIFICANCE AND USE
5.1 Where sulfates are suspected, subgrade soils should be tested as an integral part of a geotechnical evaluation because the possibility that sulfate induced heave may occur if calcium containing stabilizers are used to improve the soils and sulfate reactions may also cause deterioration in concrete structures. When planning to treat a soil used in construction with lime, testing the soil for water soluble sulfates prior to treatment becomes very important (Note 2).  
5.2 When sulfate containing cohesive soils are treated with calcium-based stabilizers for foundation improvements, sulfates and free alumina in natural soils react with calcium and free hydroxide to form crystalline minerals, such as ettringite and thaumasite.4 Thaumasite forms when ettringite undergoes changes in the presence of carbonates at low temperatures.5 The sulfate minerals expand considerably when they are hydrated.
Note 2: For more information on the effect of treating soils containing water soluble sulfates, refer to the following publication: Little, D.N., Stabilization of Pavement Subgrades and Base Course with Lime, Kendal/Hunt Publishing Co., Dubuque, IA, 1995.
Note 3: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 These methods determine the water soluble sulfate content of cohesive soils used in construction by using the colorimetric technique. Two methods are presented in this standard. Method A is for use in the field and Method B is for use in the laboratory. The colorimetric technique involves measuring the scattering of a light beam through a solution that contains suspended particulate matter. Measurements of sulfate concentrations in construction soils can be used to guide professionals in the selection of appropriate stabilization methods and to assist in assessment of potential deterioration in concrete structures.
Note 1: These test methods are partially based on the research conducted by Texas A & M University.  
1.2 The field method, Method A, is used as a screening test for the presence of sulfates and their concentration. The laboratory method, Method B, provides better resolution than the field method.  
1.3 Ion chromatography is also an acceptable alternative method that can be used to evaluate results, however, it is outside the scope of this standard.  
1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this test method.  
1.5.1 The procedures used to specify how data are collected/recorded and calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering data.  
1.6 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 appropri...

SIGNIFICANCE AND USE
4.1 The soluble salt content may be used to correct the index properties of soils such as water content, void ratio, specific gravity, degree of saturation, and dry density.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 These test methods cover a rapid procedure for squeezing pore water from fine-grained soils for the purpose of determining the amount of soluble salts present in the extracted pore water.  
1.2 These test methods were developed for soils having a water content equal to or greater than approximately 14 %, for example, marine soils. An extensive summary of procedures for extracting pore water from soils has been presented by Kriukov and Manheim (1).2  
1.3 These test methods are not generally applicable for determining the soluble salt content of the pore water extracted from coarse-grained soils, such as clean sands and gravels.  
1.4 Test Method A provides a procedure using a refractometer with a refraction index scale; Test Method B provides a procedure using a refractometer with a parts per thousand (ppt) scale.  
1.5 Units—The values stated in SI units are to be regarded as the standard.  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 unless superseded by these test methods.  
1.6.1 The procedures used to specify how data are collected/recorded and calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering data.  
1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
5.1 Granular material being used in embankments, subgrades, and retaining wall backfill must often meet certain specifications relating to corrosion potential, such as pH and electrical resistivity. This standard is used by manufacturers, suppliers, and recipients of the materials to measure the pH of the material for acceptance for its intended use.  
5.2 Retaining wall manufactures often use a granular material specification similar to: 100 % passing the 100 mm (4 in.) sieve, 75-100 % passing the 75 mm (3 in.) sieve, and 0-15 % passing the 75 μm (No. 200) sieve. The specification may vary depending on availability of local materials.  
5.3 Since the total surface area of the material being tested affects the test results, the sample and specimen must have the same grading as the material specified or proposed for use. Reducing the particle size by crushing is not permitted since this process may alter the pH of the material and will likely not be representative of the material actually being placed in the field.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 This test method uses a pH meter to measure the pH of as-received granular material that represents what will be used in the field for embankments, subgrades, and retaining wall backfill applications. The principal use of the test method is to supplement soil resistivity measurements to identify conditions under which the corrosion of metal embedded in granular material, or in contact with the granular material may be sharply accentuated.  
1.2 The pH of granular material is often specified by agencies to meet criteria that are necessary to prevent or reduce corrosion of metal objects embedded in the granular material used in embankments, subgrade, and retaining wall backfill.  
1.3 The types of granular material that can be tested for pH using this standard are natural or manufactured coarse sand, natural or crushed stone, natural or crushed gravel, air-cooled blast furnace slag, and aggregates: lightweight, heavyweight, or normal weight. According to AASHTO M 145, these granular materials generally fall into AASHTO classification groups A-1, A-2-4, A-2-5, or A-3. The ideal material is a well-graded, free draining material that has less than 10-15 % passing the 75 μm (No. 200) sieve.  
1.4 This test is based on the volumetric method because the unit weight of the fill material will vary depending on source and project specifications.  
1.5 Units—The values stated in SI units are to be regarded as standard. Except the sieve designations, they are identified using the “alternative” system in accordance with Specification E11, such as 3 in. and No. 200, instead of the “standard” of 75 mm and 75 µm, respectively. No other units of measurement are included in this standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this test method.  
1.6.1 The procedures used to specify how data are collected/recorded and calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations fo...

SIGNIFICANCE AND USE
5.1 This test method is used to determine the presence and quantity of carbonate in a soil or soft rock specimen in terms of the calcite equivalent. The method is generally intended for use as an index of approximate carbonate content to assist with characterizing marine soils, but can be used for other soils and soft rock. Other test methods exist (such as Method C25 and Test Method D3042) to evaluate calcium carbonate equivalency for purposes of characterizing use of calcareous materials as soil modifiers or agricultural lining materials.  
5.1.1 Calcium carbonates (CaCO3) are known cementing agents, are water soluble at pH  
5.2 This test method has limitations as follows:  
5.2.1 If low carbonate contents (calcite equivalents) are measured, the user does not know whether the soil is low in carbonate content or contains cerrusite, witherite, and the like, which are carbonate species whose reactions with hydrochloric acid are either very slow or limited.  
5.2.2 Testing times may be extensive (longer than 1 hour) for some carbonate species (such as dolomite) if calcite equivalents within about 1 % are required.  
5.2.3 The effects of specimen grain size, duration of testing, pH and specimen mass are discussed in the literature.3
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection, etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 This test method covers the determination of carbonate content of soils and soft rock which can be readily broken down by mechanical effort. It is a gasometric method that uses a simple portable apparatus. Results should be clearly stated as the calcite equivalent in percent because different carbonate species cover a wide range of percent calcite equivalent as shown below for a number of carbonates:    
Species  
Cation  
Calcite
Equivalent, %  
Magnesite  
Mg  
117.0  
Dolomite  
Ca, Mg  
108.6  
Calcite  
Ca  
100.0  
Aragonite  
Ca  
100.0  
Rhodocrosite  
Mn  
87.1  
Siderite  
Fe  
86.4  
Smithsonite  
Zn  
79.8  
Witherite  
Ba  
50.7  
Cerrusite  
Pb  
37.5
For example, a 100 % dolomite would be expected to yield 108.6 % calcite equivalent while 100 % siderite would yield only 86.4 % calcite equivalent. Calcite and aragonite reactions will typically complete within about 10 minutes. This method does not distinguish between the carbonate species and such determination must be made using quantitative chemical analysis methods such as atomic absorption.  
1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information only and are not considered standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard  
1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.3.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user's objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digit...

SIGNIFICANCE AND USE
5.1 The crumb test provides a simple, quick method for field or laboratory identification of a dispersive clayey soil. The internal erosion failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (5).  
5.2 The crumb test, as originally developed by Emerson (6), was called the aggregate coherence test and had seven different categories of soil-water reactions. Sherard (5) later simplified the test by combining some soil-water reactions so that only four categories, or grades, of soil dispersion are observed during the test. The crumb test is a relatively accurate positive indicator of the presence of dispersive properties in a soil. The crumb test, however, is not a completely reliable negative indicator that soils are not dispersive. The crumb test can seldom be relied upon as a sole test method for determining the presence of dispersive clays. The double-hydrometer test (Test Method D4221) and pinhole test (Test Method D4647/D4647M) are test methods that provide valuable additional insight into the probable dispersive behavior of clay soils.
Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depends on several factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 Two test methods are provided to give a qualitative indication of the natural dispersive characteristics of clayey soils: Method A and Method B.  
1.1.1 Method A—Procedure for Natural Soil Crumbs described in 10.1.  
1.1.2 Method B—Procedure for Remolded Soil Crumbs described in 10.2.  
1.2 The crumb test, while a good, quick indication of dispersive soil, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods D4647/D4647M and D4221, respectively. Since this test method may not identify all dispersive clay soils, other tests such as, pinhole dispersion (Test Methods D4647/D4647M), double hydrometer (Test Method D4221) and the analysis of pore water extraction (Test Methods D4542) may be performed individually or used together to help verify dispersion.  
1.3 The crumb test has some limitations in its usefulness as an indicator of dispersive soil. A dispersive soil may sometimes give a non-dispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems, have shown non-dispersive reactions in the crumb test (1).2 However, if the crumb test indicates dispersion, the soil is probably dispersive.  
1.4 These test methods are applicable only to soils where the position of the plasticity index versus liquid limit plots (Test Methods D4318) falls on or above the “A” line (Practice D2487) and more than 12 % of the soil fraction is finer than 2-μm as determined in accordance with Test Method D7928.  
1.5 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion (2).
Note 1: In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. The crumb test is a better indicator of dispersive soils than of non-dispersive soils (3).  
1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.7 All observed and calculated values shall conform to the guidelines for significant digits and rounding establish...

SIGNIFICANCE AND USE
5.1 The pinhole test provides one method of identifying the dispersive characteristics of clay soils that are to be or have been used in earth construction. The piping failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to the colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (2).  
5.2 This test method models the action of water flowing along a crack in an earth embankment. Other indirect tests, such as the double hydrometer test (Test Method D4221), the crumb test (3, 4), that relates the turbidity of a cloud of suspended clay colloids as an indicator of the clay dispersivity, and chemical tests that relate the percentage of sodium to total soluble salt content of the soil are also used as indicator tests of clay dispersibility (2). The comparison of results from the pinhole test and other indirect tests on hundreds of samples indicates that the results of the pinhole test have the best correlation with the erosional performance of clay soils in nature.  
5.3 Method A and Method C of the pinhole test require the evaluation of cloudiness of effluent, final size of the pinhole, and computation of flow rates through the pinhole in order to classify the dispersive characteristics of the soil. Method B requires only the evaluation of the cloudiness of effluent and final size of the pinhole to classify the dispersive characteristics of the soil. The computation of flow rates through the pinhole in Method A serves primarily as a guide to the proper equipment and specimen performance under sequential pressures applied during the test. All methods produce similar results and any method can be used to identify dispersive clays.  
5.4 The use of Method A or Method C results in the accumulation of data relative to sequential flow rates through the pinhole and consequent enlargement or erosion of the hole. The pinhole erosion test was dev...
SCOPE
1.1 This test method presents a direct, measurement of the dispersibility and consequent colloidal erodibility of clay soils by causing water to flow through a small hole punched in a specimen. The results of the tests are qualitative and provide general guidance regarding dispersibility and erodibility. This test method is complemented by Test Method D4221.  
1.2 This test method and the criteria for evaluating test data are based upon results of several hundred tests on samples collected from embankments, channels, and other areas where clay soils have eroded or resisted erosion in nature (1).2  
1.3 Three alternative procedures for classifying the dispersibility of clay soils are provided as follows:  
1.3.1 Method A and Method C, adapted from Ref  (1), classify soils into six categories of dispersiveness as: dispersibility (D1, D2), slight to moderately dispersive (ND4, ND3), and nondispersive (ND2, ND1).  
1.3.2 Method B classifies soils into three categories of dispersiveness as: dispersibility (D), slightly dispersive (SD), and nondispersive (ND).  
1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 This international standard was developed in accordance with internationally recognized principles...

SIGNIFICANCE AND USE
5.1 This test method is intended for use in determining the volume and the volume distribution of pores in soil and rock with respect to the apparent diameter of the entrances of the pores. In general, both the size and volume of the pores affects the performance of soil and rock. Thus, the pore volume distribution is useful in understanding soil and rock performance and in identifying a material that can be expected to perform in a particular manner (1, 2).3  
5.2 The intrusion process to determine the volume of a pore proceeds from the outside of a specimen toward its center. Comparatively large interior pores can exist that have smaller outside openings as the only means of access. Mercury intrusion porosimetry will incorrectly register the entire volume of these “ink-bottle” pores as having the apparent diameter of the smaller access pores. In a test specimen, exterior specimen pores can exist in addition to intra-specimen pores (see 3.2 for definitions). The inter-fragment pores will vary in size and volume depending on the size and shape of the soil or rock fragments and on the manner in which the fragments are packed together. It is possible that some exterior specimen pores can have the same apparent diameter as some intra-specimen pores. When this occurs, this test method cannot distinguish between them. Thus, the test method yields an intruded pore volume distribution that is in part dependent upon the packing of multifragment specimens. However, most soils and rocks have intra-fragment pores much smaller than the inter-fragment pores. This situation leads to a bi-modal pore size distribution and the distinction between the two classes of pores can then be made (see Figs. 1 and 2). The intr-fragment pore concentration is shown to the left of the plot; the inter-fragment concentration is to the right.
FIG. 1 Example of Cumulative Pore Volume Distribution Plot  
FIG. 2 Example of Differential Pore Volume Distribution Plot  
Note 1: The quality of the re...
SCOPE
1.1 This test method covers the determination of the pore volume and the pore volume distributions of soil and rock by the mercury intrusion porosimetry method. The range of apparent diameters of pores for which this test method is applicable is fixed by the operating pressure range of the testing instrument. This range is typically between apparent pore entrance diameters of about 400 μm and 2.5 nm (0.0025 μm). Larger pores must be measured by another method.  
1.2 Mercury intrusion porosimetry is useful only for measuring pores open to the outside of a soil or rock fragment; mercury intrusion porosimetry will not give the volume of any pores completely enclosed by surrounding solids. This test method will give only the volume of intrudable pores that have an apparent diameter corresponding to a pressure within the pressurizing range of the testing instrument.  
1.3 Mercury intrusion may involve the application of high pressures to the specimen. This may result in a temporary or permanent alteration or both in the pore geometry. Generally, soils and rocks are composed of comparatively strong solids and are less subject to these alterations than certain other materials. However, the possibility remains that the use of this test method may alter the natural pore volume distribution that is being measured.  
1.4 Warning—Mercury has been designated by EPA and many state agencies as a hazardous material that can cause central nervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA’s website (http://www.epa.gov/mercury/faq.htm) for additional information. Users should be aware that selling mercury or mercury-containing products or both into your state may be prohibited by state law.  
1.5 Units—The valu...

SIGNIFICANCE AND USE
5.1 Dispersive clays are those which normally deflocculate when exposed to water of low-salt concentration, the opposite of aggregated clays that would remain flocculated in the same soil-water system  (3, 4, 7). Generally, dispersive clays are highly erosive, possibly subject to high shrink-swell potential, may have lower shear strength, and have lower permeability rates than aggregated clays.  
5.2 When the percent dispersion equals 100, it indicates a completely dispersive clay-size fraction. When the percent dispersion equals 0, it indicates completely nondispersive clay-size fraction.  
5.3 Available data (1) indicates that the test method has about 85 % reliance in predicting dispersive performance (85 % of dispersive clays show more than 35 % dispersion).  
5.4 Since this test method may not identify all dispersive clays, design decisions based solely on this test method may not be conservative. It is often run in conjunction with the crumb test (D6572) (4, 7), the pinhole test (D4647/D4647M), or the analysis of the pore water extract (D4542) (4, 7), or combination thereof, to identify possible dispersive clay behavior.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personal performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depends on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 This test method provides an indication of the natural dispersive characteristics of clay soils by comparing the amount of particles finer than 2-μm as determined by this method compared to the amount of particles finer than 2-μm as determined by Test Method D7928 (1).2 In order to do this comparison, two similar specimens must be obtained from the sample.  
1.2 This test method follows the procedure given in Test Method D7928 with the exception that the soil slurry is not mechanically dispersed and no dispersing agent is added.  
1.3 This test method is applicable only to soils where the position of the plasticity index versus liquid limit plots (Test Methods D4318) falls on or above the “A” line (Practice D2487) and more than 12 % of the soil fraction is finer than 2-μm as determined in accordance with Test Method D7928 (2).  
1.4 Since this test method may not identify all dispersive clay soils, other tests such as, pinhole dispersion (Test Methods D4647/D4647M), crumb (Test Methods D6572) (3-5) and the analysis of pore water extraction (Test Methods D4542) (4-7) may be performed individually or used together to help verify dispersion.  
1.5 Units—The values stated in SI units are to be regarded as the standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this test method.  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.6.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user's objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.  
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use...

SIGNIFICANCE AND USE
5.1 The crumb test provides a simple, quick method for field or laboratory identification of a dispersive clayey soil. The internal erosion failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (5).  
5.2 The crumb test, as originally developed by Emerson (6), was called the aggregate coherence test and had seven different categories of soil-water reactions. Sherard (5) later simplified the test by combining some soil-water reactions so that only four categories, or grades, of soil dispersion are observed during the test. The crumb test is a relatively accurate positive indicator of the presence of dispersive properties in a soil. The crumb test, however, is not a completely reliable negative indicator that soils are not dispersive. The crumb test can seldom be relied upon as a sole test method for determining the presence of dispersive clays. The double-hydrometer test (Test Method D4221) and pinhole test (Test Method D4647/D4647M) are test methods that provide valuable additional insight into the probable dispersive behavior of clay soils.
Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depends on several factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 Two test methods are provided to give a qualitative indication of the natural dispersive characteristics of clayey soils: Method A and Method B.  
1.1.1 Method A—Procedure for Natural Soil Crumbs described in 10.1.  
1.1.2 Method B—Procedure for Remolded Soil Crumbs described in 10.2.  
1.2 The crumb test, while a good, quick indication of dispersive soil, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods D4647/D4647M and D4221, respectively. Since this test method may not identify all dispersive clay soils, other tests such as, pinhole dispersion (Test Methods D4647/D4647M), double hydrometer (Test Method D4221) and the analysis of pore water extraction (Test Methods D4542) may be performed individually or used together to help verify dispersion.  
1.3 The crumb test has some limitations in its usefulness as an indicator of dispersive soil. A dispersive soil may sometimes give a non-dispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems, have shown non-dispersive reactions in the crumb test (1).2 However, if the crumb test indicates dispersion, the soil is probably dispersive.  
1.4 These test methods are applicable only to soils where the position of the plasticity index versus liquid limit plots (Test Methods D4318) falls on or above the “A” line (Practice D2487) and more than 12 % of the soil fraction is finer than 2-μm as determined in accordance with Test Method D7928.  
1.5 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion (2).
Note 1: In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. The crumb test is a better indicator of dispersive soils than of non-dispersive soils (3).  
1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.7 All observed and calculated values shall conform to the guidelines for significant digits and rounding establish...

SIGNIFICANCE AND USE
5.1 Dispersive clays are those which normally deflocculate when exposed to water of low-salt concentration, the opposite of aggregated clays that would remain flocculated in the same soil-water system  (3, 4, 7). Generally, dispersive clays are highly erosive, possibly subject to high shrink-swell potential, may have lower shear strength, and have lower permeability rates than aggregated clays.  
5.2 When the percent dispersion equals 100, it indicates a completely dispersive clay-size fraction. When the percent dispersion equals 0, it indicates completely nondispersive clay-size fraction.  
5.3 Available data (1) indicates that the test method has about 85 % reliance in predicting dispersive performance (85 % of dispersive clays show more than 35 % dispersion).  
5.4 Since this test method may not identify all dispersive clays, design decisions based solely on this test method may not be conservative. It is often run in conjunction with the crumb test (D6572) (4, 7), the pinhole test (D4647/D4647M), or the analysis of the pore water extract (D4542) (4, 7), or combination thereof, to identify possible dispersive clay behavior.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personal performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depends on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 This test method provides an indication of the natural dispersive characteristics of clay soils by comparing the amount of particles finer than 2-μm as determined by this method compared to the amount of particles finer than 2-μm as determined by Test Method D7928 (1).2 In order to do this comparison, two similar specimens must be obtained from the sample.  
1.2 This test method follows the procedure given in Test Method D7928 with the exception that the soil slurry is not mechanically dispersed and no dispersing agent is added.  
1.3 This test method is applicable only to soils where the position of the plasticity index versus liquid limit plots (Test Methods D4318) falls on or above the “A” line (Practice D2487) and more than 12 % of the soil fraction is finer than 2-μm as determined in accordance with Test Method D7928 (2).  
1.4 Since this test method may not identify all dispersive clay soils, other tests such as, pinhole dispersion (Test Methods D4647/D4647M), crumb (Test Methods D6572) (3-5) and the analysis of pore water extraction (Test Methods D4542) (4-7) may be performed individually or used together to help verify dispersion.  
1.5 Units—The values stated in SI units are to be regarded as the standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this test method.  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.6.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user's objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.  
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use...

SIGNIFICANCE AND USE
4.1 The soluble salt content may be used to correct the index properties of soils such as water content, void ratio, specific gravity, degree of saturation, and dry density).  
4.2 Minimize the time period between sampling and testing to reduce chemical changes, which may occur within the soil sample.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
Note 2: Hulbert and Brindle (2) and Torrance (3) have shown that prolonged storage should be avoided as unpredictable and non-reproducible chemical changes may occur.
SCOPE
1.1 These test methods cover a rapid procedure for squeezing pore water from finegrained soils for the purpose of determining the amount of soluble salts present in the extracted pore water.  
1.2 These test methods were developed for soils having a water content equal to or greater than approximately 14 %, for example, marine soils. An extensive summary of procedures for extracting pore water from soils has been presented by Kriukov and Manheim (1).2  
1.3 These test methods are not generally applicable for determining the soluble salt content of the pore water extracted from coarse-grained soils, such as clean sands and gravels.  
1.4 Test Method A provides a procedure using a refractometer with a refraction index scale; Test Method B provides a procedure using a refractometer with a parts per thousand (ppt) scale.  
1.5 Units—The values stated in SI units are to be regarded as the standard.  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 unless superseded by these test methods.  
1.6.1 The procedures used to specify how data are collected/recorded and calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering data.  
1.7 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.  
1.8 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.

SIGNIFICANCE AND USE
5.1 This test method is used to determine the presence and quantity of carbonate in a soil specimen in terms of the calcite equivalent. The method is generally intended for use as an index of approximate carbonate content to assist with characterizing marine soils. Other test methods exist (such as Method C25 and Test Method D3042) to evaluate calcium carbonate equivalency for purposes of characterizing use of calcareous materials as soil modifiers or agricultural lining materials.  
5.1.1 Calcium carbonates (CaCO3) are known cementing agents, are water soluble at pH  
5.2 This test method has limitations as follows:  
5.2.1 If low carbonate contents (calcite equivalents) are measured, the user does not know whether the soil is low in carbonate content or contains cerrusite, witherite, and the like, which are carbonate species whose reactions with hydrochloric acid are either very slow or limited.  
5.2.2 Testing times may be extensive (longer than 1 hour) for some carbonate species (such as dolomite) if calcite equivalents within about 1 % are required.  
5.2.3 The effects of specimen grain size, duration of testing, pH and specimen mass are discussed in the literature.3Note 1—The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection, etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 This test method covers the determination of carbonate content of soils and soft rock which can be readily broken down by mechanical effort. It is a gasometric method that uses a simple portable apparatus. Results should be clearly stated as the calcite equivalent in percent because different carbonate species cover a wide range of percent calcite equivalent as shown below for a number of carbonates:    
Species  
Cation  
Calcite
Equivalent, %  
Magnesite  
Mg  
117.0  
Dolomite  
Ca, Mg  
108.6  
Calcite  
Ca  
100.0  
Aragonite  
Ca  
100.0  
Rhodocrosite  
Mn  
87.1  
Siderite  
Fe  
86.4  
Smithsonite  
Zn  
79.8  
Witherite  
Ba  
50.7  
Cerrusite  
Pb  
37.5
For example, a 100 % dolomite would be expected to yield 108.6 % calcite equivalent while 100 % siderite would yield only 86.4 % calcite equivalent. Calcite and aragonite reactions will typically complete within about 10 minutes. This method does not distinguish between the carbonate species and such determination must be made using quantitative chemical analysis methods such as atomic absorption.  
1.2 Units—The values stated in SI units are to be regarded as the standard.  
1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.3.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user's objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.
1.4 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 p...

SIGNIFICANCE AND USE
5.1 The crumb test provides a simple, quick method for field or laboratory identification of a dispersive clayey soil. The internal erosion failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (5).  
5.2 The crumb test, as originally developed by Emerson (6), was called the aggregate coherence test and had seven different categories of soil-water reactions. Sherard (5) later simplified the test by combining some soil-water reactions so that only four categories, or grades, of soil dispersion are observed during the test. The crumb test is a relatively accurate positive indicator of the presence of dispersive properties in a soil. The crumb test, however, is not a completely reliable negative indicator that soils are not dispersive. The crumb test can seldom be relied upon as a sole test method for determining the presence of dispersive clays. The double-hydrometer test (Test Method D4221) and pinhole test (Test Method D4647) are test methods that provide valuable additional insight into the probable dispersive behavior of clay soils.Note 2—The quality of the result produced by these test methods is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of these test methods are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depends on several factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 Two test methods are provided to give a qualitative indication of the natural dispersive characteristics of clayey soils: Method A and Method B.  
1.1.1 Method A—Procedure for Natural Soil Crumbs described in 10.2.  
1.1.2 Method B—Procedure for Remolded Soil Crumbs described in 10.3.  
1.2 The crumb test, while a good, quick indication of dispersive soil, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods D4647 and D4221, respectively.  
1.3 The crumb test has some limitations in its usefulness as an indicator of dispersive soil. A dispersive soil may sometimes give a non-dispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems, have shown non-dispersive reactions in the crumb test (1).2 However, if the crumb test indicates dispersion, the soil is probably dispersive.  
1.4 These test methods are not applicable for soils with 12 % or less of the particles passing 0.005 mm and having a plasticity index less than or equal to 8, as determined by Test Method D4318.  
1.5 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion (2).Note 1—In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. The crumb test is a better indicator of dispersive soils than of non-dispersive soils (3).  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.6.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this stan...

SIGNIFICANCE AND USE
5.1 The crumb test provides a simple, quick method for field or laboratory identification of a dispersive clayey soil. The internal erosion failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (5).  
5.2 The crumb test, as originally developed by Emerson (6), was called the aggregate coherence test and had seven different categories of soil-water reactions. Sherard (5) later simplified the test by combining some soil-water reactions so that only four categories, or grades, of soil dispersion are observed during the test. The crumb test is a relatively accurate positive indicator of the presence of dispersive properties in a soil. The crumb test, however, is not a completely reliable negative indicator that soils are not dispersive. The crumb test can seldom be relied upon as a sole test method for determining the presence of dispersive clays. The double-hydrometer test (Test Method D4221) and pinhole test (Test Method D4647) are test methods that provide valuable additional insight into the probable dispersive behavior of clay soils.Note 2—The quality of the result produced by these test methods is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of these test methods are cautioned that compliance with Practice D3740 does not in itself ensure reliable testing. Reliable testing depends on several factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 Two test methods are provided to give a qualitative indication of the natural dispersive characteristics of clayey soils:. Method A and Method B.  
1.1.1 Method A—Procedure for Natural Soil Crumbs described in 10.2.  
1.1.2 Method B—Procedure for Remolded Soil Crumbs described in 10.3.  
1.2 The crumb test, while a good, quick indication of dispersive soil, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods A6 and A5, respectively.  
1.3 The crumb test has some limitations in its usefulness as an indicator of dispersive soil. A dispersive soil may sometimes give a non-dispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems, have shown non-dispersive reactions in the crumb test (1).2 However, if the crumb test indicates dispersion, the soil is probably dispersive.  
1.4 These test methods are not applicable for soils with 12 % or less of the particles passing 0.005 mm and having a plasticity index less than or equal to 8, as determined by Test Method A9.  
1.5 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion (2).Note 1—In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. The crumb test is a better indicator of dispersive soils than of non-dispersive soils (3).  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.6.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to ...

SIGNIFICANCE AND USE
5.1 The crumb test provides a simple, quick method for field or laboratory identification of a dispersive clayey soil. The internal erosion failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (5).  
5.2 The crumb test, as originally developed by Emerson (6), was called the aggregate coherence test and had seven different categories of soil-water reactions. Sherard (5) later simplified the test by combining some soil-water reactions so that only four categories, or grades, of soil dispersion are observed during the test. The crumb test is a relatively accurate positive indicator of the presence of dispersive properties in a soil. The crumb test, however, is not a completely reliable negative indicator that soils are not dispersive. The crumb test can seldom be relied upon as a sole test method for determining the presence of dispersive clays. The double-hydrometer test (Test Method D4221) and pinhole test (Test Method D4647) are test methods that provide valuable additional insight into the probable dispersive behavior of clay soils.
Note 2: The quality of the result produced by these test methods is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of these test methods are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depends on several factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 Two test methods are provided to give a qualitative indication of the natural dispersive characteristics of clayey soils: Method A and Method B.  
1.1.1 Method A—Procedure for Natural Soil Crumbs described in 10.2.  
1.1.2 Method B—Procedure for Remolded Soil Crumbs described in 10.3.  
1.2 The crumb test, while a good, quick indication of dispersive soil, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods D4647 and D4221, respectively.  
1.3 The crumb test has some limitations in its usefulness as an indicator of dispersive soil. A dispersive soil may sometimes give a non-dispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems, have shown non-dispersive reactions in the crumb test (1).2 However, if the crumb test indicates dispersion, the soil is probably dispersive.  
1.4 These test methods are not applicable for soils with 12 % or less of the particles passing 0.005 mm and having a plasticity index less than or equal to 8, as determined by Test Method D4318.  
1.5 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion (2).
Note 1: In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. The crumb test is a better indicator of dispersive soils than of non-dispersive soils (3).  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.6.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of t...

SIGNIFICANCE AND USE
5.1 The pinhole test provides one method of identifying the dispersive characteristics of clay soils that are to be or have been used in earth construction. The piping failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to the colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (2).  
5.2 This test method models the action of water flowing along a crack in an earth embankment. Other indirect tests, such as the double hydrometer test (Test Method D4221), the crumb test (3, 4), that relates the turbidity of a cloud of suspended clay colloids as an indicator of the clay dispersivity, and chemical tests that relate the percentage of sodium to total soluble salt content of the soil are also used as indicator tests of clay dispersibility (2). The comparison of results from the pinhole test and other indirect tests on hundreds of samples indicates that the results of the pinhole test have the best correlation with the erosional performance of clay soils in nature.  
5.3 Method A and Method C of the pinhole test require the evaluation of cloudiness of effluent, final size of the pinhole, and computation of flow rates through the pinhole in order to classify the dispersive characteristics of the soil. Method B requires only the evaluation of the cloudiness of effluent and final size of the pinhole to classify the dispersive characteristics of the soil. The computation of flow rates through the pinhole in Method A serves primarily as a guide to the proper equipment and specimen performance under sequential pressures applied during the test. All methods produce similar results and any method can be used to identify dispersive clays.  
5.4 The use of Method A or Method C results in the accumulation of data relative to sequential flow rates through the pinhole and consequent enlargement or erosion of the hole. The pinhole erosion test was d...
SCOPE
1.1 This test method presents a direct, measurement of the dispersibility and consequent colloidal erodibility of clay soils by causing water to flow through a small hole punched in a specimen. The results of the tests are qualitative and provide general guidance regarding dispersibility and erodibility. This test method is complemented by Test Method D4221.  
1.2 This test method and the criteria for evaluating test data are based upon results of several hundred tests on samples collected from embankments, channels, and other areas where clay soils have eroded or resisted erosion in nature (1).2  
1.3 Three alternative procedures for classifying the dispersibility of clay soils are provided as follows:  
1.3.1 Method A and Method C, adapted from Ref  (1), classify soils into six categories of dispersiveness as: dispersibility (D1, D2), slight to moderately dispersive (ND4, ND3), and nondispersive (ND2, ND1).  
1.3.2 Method B classifies soils into three categories of dispersiveness as: dispersibility (D), slightly dispersive (SD), and nondispersive (ND).  
1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.6 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.

SIGNIFICANCE AND USE
5.1 The crumb test method provides a simple, quick method for field or laboratory identification of a dispersive clay soil. The internal erosion failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (5).  
5.2 The crumb test method, as originally developed by Emerson (6), was called the aggregate coherence test and had seven different categories of soil-water reactions. Sherard (5) later simplified the test by combining some soil-water reactions so that only four categories, or grades, of soil dispersion are observed during the test. The crumb test is a relatively accurate positive indicator of the presence of dispersive properties in a soil. The crumb test, however, is not a completely reliable negative indicator that soils are not dispersive. The crumb test can seldom be relied upon as a sole test method for determining the presence of dispersive clays. The double-hydrometer test (Test Method D4221) and pinhole test (Test Method D4647) are test methods that provide valuable additional insight into the probable dispersive behavior of clay soils.Note 2—The quality of the result produced by these test methods is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of these test methods are cautioned that compliance with Practice D3740 does not in itself ensure reliable testing. Reliable testing depends on several factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 Two test methods are provided to give a qualitative indication of the natural dispersive characteristics of clayey soils. Method A is for natural soil clumps and method B for remolded soil.  
1.2 These test methods are not applicable for soils with less than 12 % finer than 0.005 mm and with a plasticity index less than or equal to 8.  
1.3 The crumb test method has some limitations in its usefulness as an indicator of dispersive clay. A dispersive soil may sometimes give a non-dispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems have shown non-dispersive reactions in the crumb test (1)2. However, if the crumb test indicates dispersion, the soil is probably dispersive.  
1.4 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion (2).  
1.5 The crumb test method, while a good quick indication of dispersive clay, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods D4647 and D4221, respectively.Note 1—In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. Crumb test methods are a better indicator of dispersive clays than of nondispersive clays (3).  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.6.1 The method used to specify how data are collected, calculated, or recorded in this standard is not directly related to the accuracy to which the data can be applied in design or other uses, or both. How one applies the results obtained using this standard is beyond its scope.  
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.8 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 limitat...

SIGNIFICANCE AND USE
Dispersive clays are those which normally deflocculate when exposed to water of low-salt concentration, the opposite of aggregated clays that would remain flocculated in the same soil-water system  (3, 4, 7). Generally, dispersive clays are highly erosive, possibly subject to high shrink-swell potential, may have lower shear strength, and have lower permeability rates than aggregated clays.
Available data (1) indicates that the test method has about 85 % reliance in predicting dispersive performance (85 % of dispersive clays show more than 35 % dispersion).
Since this test method may not identify all dispersive clays, design decisions based solely on this test method may not be conservative. It is often run in conjunction with the crumb test (4, 7), the pinhole test given in Test Method D4647, or the analysis of the pore water extract (4, 7), or combination thereof, to identify possible dispersive clay behavior.
Note 1—Notwithstanding the statement on precision and bias contained in this test method; the precision of this test method is dependent on the competence of the personal performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of this test method are cautioned that compliance with Practice D3740 does not in itself ensure reliable testing. Reliable testing depends on several factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 This test method, when used in conjunction with a test performed by Test Method D422 on a duplicate soil sample, provides an indication of the natural dispersive characteristics of clay soils (1).  
1.2 This test method is applicable only to soils with a plasticity index greater than 4 as determined in accordance with Test Method D4318 and more than 12 % of the soil fraction finer than 5-μm as determined in accordance with Test Method D422 (2).  
1.3 This test method is similar to Test Method D422, except that this method covers the determination of percent of soil particles smaller than 5-μm in diameter in a soil-water suspension without mechanical agitation and to which no dispersing agent has been added.  
1.4 The amount of particles smaller than 5-μm determined by this method compared with the total amount of particles smaller than 5-μm determined by Test Method D422 is a measure of the dispersive characteristics of the soil.
1.5 This test method may not identify all dispersive clay soils. Pinholes (Test Method D4647 and crumb tests, or both, (3-5)or the analysis of pore water extract (4-7) may be performed to help verify dispersion.
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.8 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.

SIGNIFICANCE AND USE
This test method can be used to make reliable and reproducible measurements in soil in the range from the detection level to the percent levels of each of seven explosive compounds.
This test method does not attempt to quantify the reactivity or mobility of the explosive content, only the concentration of these compounds in the soil.
This test method can be used to determine the extent of contamination resulting from the use, misuse, or spillage of explosive compounds. It is useful to determine the effectiveness of clean-up actions at disposal sites, and to determine the environmental impact at explosives disposal, manufacturing, or storage sites.
SCOPE
1.1 This test method describes a procedure for the laboratory determination of the concentration of nitroaromatic and nitramine explosives in soil. The explosives involved in this test method are as follows: HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), RDX (hexahydro-1,3,5-trinitrol-1,3,5-triazine), TNT (2,4,6-trinitrotoluene), TNB (1,3,5 trinitrobenzene), DNB (1,3 dinitrobenzene), tetryl (methyl-2,4,6-trinitrophenylnitramine), and 2,4-DNT (2,4-dinitrotoluene).  
1.2 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026  
1.2.1 The method used to specify how data are collected, calculated, or recorded in this standard is not directly related to the accuracy to which the data can be applied in design of other uses, or both. How one applies the results obtained using this standard is beyond its scope. (See Practice D3740)
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 This standard does not purport to address the safety concerns 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.

SIGNIFICANCE AND USE
This test method is intended for use in determining the volume and the volume distribution of pores in soil and rock with respect to the apparent diameter of the entrances of the pores. In general, both the size and volume of the pores affects the performance of soil and rock. Thus, the pore volume distribution is useful in understanding soil and rock performance and in identifying a material that can be expected to perform in a particular manner (1, 2).  
The intrusion process to determine the volume of a pore proceeds from the outside of a specimen toward its center. Comparatively large interior pores can exist that have smaller outside openings as the only means of access. Mercury intrusion porosimetry will incorrectly register the entire volume of these “ink-bottle” pores as having the apparent diameter of the smaller access pores. In a test specimen, exterior specimen pores can exist in addition to intra-specimen pores (see Section 3 for definitions). The inter-fragment pores will vary in size and volume depending on the size and shape of the soil or rock fragments and on the manner in which the fragments are packed together. It is possible that some exterior specimen pores can have the same apparent diameter as some intra-specimen pores. When this occurs, this test method cannot distinguish between them. Thus, the test method yields an intruded pore volume distribution that is in part dependent upon the packing of multifragment specimens. However, most soils and rocks have intra-fragment pores much smaller than the inter-fragment pores. This situation leads to a bi-modal pore size distribution and the distinction between the two classes of pores can then be made (see Figs. 1 and 2).
Note 1—Notwithstanding the statement on precision and bias contained in this test method: The precision of this test method is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies which meet the criteria ...
SCOPE
1.1 This test method covers the determination of the pore volume and the pore volume distributions of soil and rock by the mercury intrusion porosimetry method. The range of apparent diameters of pores for which this test method is applicable is fixed by the operating pressure range of the testing instrument. This range is typically between apparent pore entrance diameters of about 100 μm and 2.5 nm (0.0025 μm). Larger pores must be measured by another method.
1.2 Mercury intrusion porosimetry is useful only for measuring pores open to the outside of a soil or rock fragment; mercury intrusion porosimetry will not give the volume of any pores completely enclosed by surrounding solids. This test method will give only the volume of intrudable pores that have an apparent diameter corresponding to a pressure within the pressurizing range of the testing instrument.
1.3 Mercury intrusion may involve the application of high pressures to the specimen. This may result in a temporary or permanent alteration or both in the pore geometry. Generally, soils and rocks are composed of comparatively strong solids and are less subject to these alterations than certain other materials. However, the possibility remains that the use of this test method may alter the natural pore volume distribution that is being measured.
1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.
1.5 WarningMercury has been designated by EPA and many state agencies as a hazardous material that can cause central nervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA’s website (http://www.epa.gov/mercury/faq.htm) for additional information. Users should be...

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1.1 This test method covers the determination of carbonate content of soils and soft rock which can be readily broken down by mechanical effort. It is a gasometric method that utilizes a simple portable apparatus. Results should be clearly stated as the calcite equivalent in percent because different carbonate species cover a wide range of percent calcite equivalent as shown below for a number of carbonates:
For example, a 100 % dolomite would be expected to yield 108.6 % calcite equivalent while 100 % siderite would yield only 86.4 % calcite equivalent. Calcite and aragonite reactions will typically complete within about 10 min. This method does not distinguish between the carbonate species and such determination must be made using quantitative chemical analysis methods such as atomic absorption.
1.2 The values stated in SI units are to be regarded as the standard.
1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D 6026.
1.4 The method used to specify how data are collected, calculated, or recorded in this standard is not directly related to the accuracy to which the data can be applied in design or other uses, or both. How one applies the results obtained using this standard is beyond its scope.
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. For specific precaution statements, see Section 8.

SIGNIFICANCE AND USE
The soluble salt content may be used to correct the index properties of soils (water content, void ratio, specific gravity, degree of saturation, and dry density).
It is necessary to minimize the time period between sampling and testing due to chemical changes which may occur within the soil sample.
Note 1—The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D 3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D 3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D 3740 provides a means of evaluating some of those factors.
Note 2—Hulbert and Brindle (2) and Torrance (3) have shown that prolonged storage should be avoided as unpredictable and nonreproducible chemical changes may occur.
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1.1 This test method covers a rapid procedure for squeezing pore water from fine-grained soils for the purpose of determining the amount of soluble salts present in the extracted pore water.
1.2 This test method was developed for soils having a water content equal to or greater than approximately 14 %, for example, marine soils. An extensive summary of procedures for extracting pore water from soils has been presented by Kriukov and Manheim  (1).
1.3 This test method is not generally applicable for determining the soluble salt content of the pore water extracted from coarse-grained soils, such as clean sands and gravels.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
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.
1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D 6026.

SCOPE
1.1 This test method presents a direct, qualitative measurement of the dispersibility and consequent colloidal erodibility of clay soils by causing water to flow through a small hole punched in a specimen. This test method is complemented by Test Method D 4221.
1.2 This test method and the criteria for evaluating test data are based upon results of several hundred tests on samples collected from embankments, channels, and other areas where clay soils have eroded or resisted erosion in nature (1).
1.3 Three alternative procedures for classifying the dispersibility of clay soils are provided as follows:
1.3.1 Method A and Method C, adapted from Ref  (1), classify soils into six categories of dispersiveness as: dispersibility (D1, D2), slight to moderately dispersive (ND4, ND3), and nondispersive (ND2, ND1).
1.3.2 Method B classifies soils into three categories of dispersiveness as: dispersibility (D), slightly dispersive (SD), and nondispersive (ND).
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.
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.

SIGNIFICANCE AND USE
This test method can be used to make reliable and reproducible measurements in soil in the range from the detection level to the percent levels of each of seven explosive compounds.
This test method does not attempt to quantify the reactivity or mobility of the explosive content, only the concentration of these compounds in the soil.
This test method can be used to determine the extent of contamination resulting from the use, misuse, or spillage of explosive compounds. It is useful to determine the effectiveness of clean-up actions at disposal sites, and to determine the environmental impact at explosives disposal, manufacturing, or storage sites.
SCOPE
1.1 This test method describes a procedure for the laboratory determination of the concentration of nitroaromatic and nitramine explosives in soil. The explosives involved in this test method are as follows: HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), RDX (hexahydro-1,3,5-trinitrol-1,3,5-triazine), TNT (2,4,6-trinitrotoluene), TNB (1,3,5 trinitrobenzene), DNB (1,3 dinitrobenzene), tetryl (methyl-2,4,6-trinitrophenylnitramine), and 2,4-DNT (2,4-dinitrotoluene).
1.2 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D 6026
1.2.1 The method used to specify how data are collected, calculated, or recorded in this standard is not directly related to the accuracy to which the data can be applied in design of other uses, or both. How one applies the results obtained using this standard is beyond its scope.
1.3 The values stated in SI units are to be regarded as the standard.
This standard does not purport to address the safety concerns 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.

SIGNIFICANCE AND USE
The crumb test method provides a simple, quick method for field or laboratory identification of a dispersive clay soil. The internal erosion failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (5).
The crumb test method, as originally developed by Emerson (6), was called the aggregate coherence test and had seven different categories of soil-water reactions. Sherard (5) later simplified the test by combining some soil-water reactions so that only four categories, or grades, of soil dispersion are observed during the test. The crumb test is a relatively accurate positive indicator of the presence of dispersive properties in a soil. The crumb test, however, is not a completely reliable negative indicator that soils are not dispersive. The crumb test, can seldom be relied upon as a sole test method for determining the presence of dispersive clays. The double-hydrometer test (Test Method D 4221) and pinhole test (Test Method D 4647) are test methods that provide valuable additional insight into the probable dispersive behavior of clay soils.
Note 2—The quality of the result produced by these test methods is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D 3740 are generally considered capable of competent and objective testing. Users of these test methods are cautioned that compliance with Practice D 3740 does not in itself ensure reliable testing. Reliable testing depends on several factors; Practice D 3740 provides a means of evaluating some of those factors.
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1.1 These test methods provide a qualitative indication of the natural dispersive characteristics of clayey soils.
1.2 These test methods are not applicable for soils with less than 12 % fraction finer than 0.005 mm and with a plasticity index less than or equal to 8.
1.3 The crumb test method has some limitations in its usefulness as an indicator of dispersive clay. A dispersive soil may sometimes give a nondispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems have shown nondispersive reactions in the crumb test (). However, if the crumb test indicates dispersion, the soil is probably dispersive.
1.4 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion ().
1.5 The crumb test method, while a good quick indication of dispersive clay, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods D 4647 and D 4221, respectively.Note 1
In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. Crumb test methods are a better indicator of dispersive clays than of nondispersive clays ().
1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
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.

SIGNIFICANCE AND USE
The pinhole test provides one method of identifying the dispersive characteristics of clay soils that are to be or have been used in earth construction. The piping failures of a number of homogeneous earth dams, erosion along channel or canal banks, and rainfall erosion of earthen structures have been attributed to the colloidal erosion along cracks or other flow channels formed in masses of dispersive clay (2).
This test method models the action of water flowing along a crack in an earth embankment. Other indirect tests, such as the double hydrometer test (Test Method D 4221), the crumb test (3, 4), that relates the turbidity of a cloud of suspended clay colloids as an indicator of the clay dispersivity, and chemical tests that relate the percentage of sodium to total soluble salt content of the soil are also used as indicator tests of clay dispersibility (2). The comparison of results from the pinhole test and other indirect tests on hundreds of samples indicates that the results of the pinhole test have the best correlation with the erosional performance of clay soils in nature.  
Method A and Method C of the pinhole test require the evaluation of cloudiness of effluent, final size of the pinhole, and computation of flow rates through the pinhole in order to classify the dispersive characteristics of the soil. Method B requires only the evaluation of the cloudiness of effluent and final size of the pinhole to classify the dispersive characteristics of the soil. The computation of flow rates through the pinhole in Method A serves primarily as a guide to the proper equipment and specimen performance under sequential pressures applied during the test. All methods produce similar results and any method can be used to identify dispersive clays.
The use of Method A or Method C results in the accumulation of data relative to sequential flow rates through the pinhole and consequent enlargement or erosion of the hole. The pinhole erosion test was developed for the pu...
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1.1 This test method presents a direct, qualitative measurement of the dispersibility and consequent colloidal erodibility of clay soils by causing water to flow through a small hole punched in a specimen. This test method is complemented by Test Method D 4221.  
1.2 This test method and the criteria for evaluating test data are based upon results of several hundred tests on samples collected from embankments, channels, and other areas where clay soils have eroded or resisted erosion in nature (1).  
1.3 Three alternative procedures for classifying the dispersibility of clay soils are provided as follows:
1.3.1 Method A and Method C, adapted from Ref  (1), classify soils into six categories of dispersiveness as: dispersibility (D1, D2), slight to moderately dispersive (ND4, ND3), and nondispersive (ND2, ND1).
1.3.2 Method B classifies soils into three categories of dispersiveness as: dispersibility (D), slightly dispersive (SD), and nondispersive (ND).
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.
1.5 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.

SCOPE
1.1 This test method presents a direct, qualitative measurement of the dispersibility and consequent colloidal erodibility of clay soils by causing water to flow through a small hole punched in a specimen. This test method is complemented by Test Method D4221.  
1.2 This test method and the criteria for evaluating test data are based upon results of several hundred tests on samples collected from embankments, channels, and other areas where clay soils have eroded or resisted erosion in nature (1).  
1.3 Three alternative procedures for classifying the dispersibility of clay soils are provided as follows:  
1.3.1 Method A and Method C, adapted from Ref (1), classify soils into six categories of dispersiveness as: dispersibility (D1, D2), slight to moderately dispersive (ND4, ND3), and nondispersive (ND2, ND1).  
1.3.2 Method B classifies soils into three categories of dispersiveness as:dispersibility (D), slightly dispersive (SD), and nondispersive (ND).  
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.  
1.5 This standard does not purport to address all of the safety problems, 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.

SIGNIFICANCE AND USE
Dispersive clays are those which normally deflocculate when exposed to water of low-salt concentration, the opposite of aggregated clays that would remain flocculated in the same soil-water system  (3, 4, 7). Generally, dispersive clays are highly erosive, possibly subject to high shrink-swell potential, may have lower shear strength, and have lower permeability rates than aggregated clays.
Available data (1) indicates that the test method has about 85 % reliance in predicting dispersive performance (85 % of dispersive clays show more than 35 % dispersion).
Since this test method may not identify all dispersive clays, design decisions based solely on this test method may not be conservative. It is often run in conjunction with the crumb test (4, 7), the pinhole test given in Test Method D 4647, or the analysis of pore water extract (4, 7), or combination thereof, to identify possible dispersive clay behavior.
Note 1—Notwithstanding the statement on precision and bias contained in this test method; the precision of this test method is dependent on the competence of the personal performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D 3740 are generally considered capable of competent and objective testing. Users of this test method are cautioned that compliance with Practice D 3740 does not in itself ensure reliable testing. Reliable testing depends on several factors; Practice D 3740 provides a means of evaluating some of those factors.
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1.1 This test method, when used in conjunction with a test performed by Test Method D 422 on a duplicate soil sample, provides an indication of the natural dispersive characteristics of clay soils ().
1.2 This test method is applicable only to soils with a plasticity index greater than 4 as determined in accordance with Test Method D 4318 and more than 12 % of the soil fraction finer than 5-m as determined in accordance with Test Method D 422 ().
1.3 This test method is similar to Test Method D 422, except that this method covers the determination of percent of soil particles smaller than 5-m in diameter in a soil-water suspension without mechanical agitation and to which no dispersing agent has been added.
1.4 The amount of particles smaller than 5-m determined by this method compared with the total amount of particles smaller than 5-m determined by Test Method D 422 is a measure of the dispersive characteristics of the soil.
1.5 This test method may not identify all dispersive clay soils. Pinholes (Test Method D 4647 and crumb tests, or both, ()or the analysis of pore water extract () may be performed to help verify dispersion.
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.

SCOPE
1.1 This test method describes a procedure for the laboratory determination of the concentration of nitroaromatic and nitramine explosives in soil. The explosives involved in this test method are as follows: HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), RDX (hexahydro-1,3,5-trinitrol-1,3,5-triazine), TNT (2,4,6-trinitrotoluene), TNB (1,3,5 trinitrobenzene), DNB (1,3 dinitrobenzene), tetryl (methyl-2,4,6-trinitrophenylnitramine), and 2,4-DNT (2,4-dinitrotoluene).
1.2 The values stated in SI units are to be regarded as the standard.
This standard does not purport to address the safety concerns 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.

SCOPE
1.1 This test method describes a procedure for the laboratory determination of the concentration of nitroaromatic and nitramine explosives in soil. The explosives involved in this test method are as follows: HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), RDX (hexahydro-1,3,5-trinitrol-1,3,5-triazine), TNT (2,4,6-trinitrotoluene), TNB (1,3,5 trinitrobenzene), DNB (1,3 dinitrobenzene), tetryl (methyl-2,4,6-trinitrophenylnitramine), and 2,4-DNT (2,4-dinitrotoluene).
1.2 The values stated in SI units are to be regarded as the standard.
This standard does not purport to address the safety concerns 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.

SIGNIFICANCE AND USE
This test method is intended for use in determining the volume and the volume distribution of pores in soil and rock with respect to the apparent diameter of the entrances of the pores. In general, both the size and volume of the pores affects the soil or rock performance. Thus, the pore volume distribution is useful in understanding soil and rock performance and in identifying a material that can be expected to perform in a particular manner (1, 2).4
SCOPE
1.1 This test method covers the determination of the pore volume and the pore volume distributions of soil and rock by the mercury intrusion porosimetry method. The range of apparent diameters of pores for which this test method is applicable is fixed by the operant pressure range of the testing instrument. This range is typically between apparent pore entrance diameters of about 100 [mu]m and 2.5 nm (0.0025 [mu]m). Larger pores must be measured by another method.  
1.2 Mercury intrusion porosimetry is useful only for measuring pores open to the outside of a soil or rock fragment; mercury intrusion porosimetry will not give the volume of any pores completely enclosed by surrounding solids. This test method will give only the volume of intrudable pores that have an apparent diameter corresponding to a pressure within the pressurizing range of the testing instrument.  
1.3 The intrusion process proceeds from the outside of a fragment toward its center. Comparatively large interior pores can exist that have smaller pores as the only means of access. Mercury intrusion porosimetry will incorrectly register the entire volume of these "ink-bottle" pores as having the apparent diameter of the smaller access pores. In a test sample, inter-fragment pores can exist in addition to intra-fragment pores (see Section 3 for definitions). The inter-fragment pores will vary in size and volume depending on the size and shape of the soil or rock fragments and on the manner in which the fragments are packed together. It is possible that some inter-fragment pores can have the same apparent diameter as some intra-fragment pores. When this occurs this test method cannot distinguish between them. Thus, the test method yields an intruded pore volume distribution that is in part dependent upon the packing of multifragment samples. However, most soils and rocks have intra-fragment pores much smaller than the inter-fragment pores. This situation leads to a bi-modal pore size distribution and the distinction between the two classes of pores can then be made (see Figs. 1 and 2).  
1.4 Mercury intrusion may involve the application of high pressures to the sample. This may result in a temporary, or permanent, or temporary and permanent alteration in the pore geometry. Generally, soils and rocks are composed of comparatively strong solids and are less subject to these alterations than certain other materials. However, the possibility remains that the use of this test method may alter the natural pore volume distribution that is being measured.  
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precaution statements, see Section 8.

SCOPE
1.1 This test method covers the determination of carbonate content of soils and soft rock which can be readily broken down by mechanical effort. It is a gasometric method that utilizes a simple portable apparatus. Results should be clearly stated as the calcite equivalent in percent because different carbonate species cover a wide range of percent calcite equivalent as shown below for a number of carbonates:SpeciesCationCalciteEquivalent, %MagnesiteMg117.0DolomiteCa, Mg108.6CalciteCa100.0AragoniteCa100.0RhodocrositeMn87.1SideriteFe86.4SmithsoniteZn79.8WitheriteBa50.7CerrusitePb37.5
For example, a 100 % dolomite would be expected to yield 108.6 % calcite equivalent while 100 % siderite would yield only 86.4 % calcite equivalent. Calcite and aragonite reactions will typically complete within about 10 min. This method does not distinguish between the carbonate species and such determination must be made using quantitative chemical analysis methods such as atomic absorption.
1.2 The values stated in SI units are to be regarded as the standard.
1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D 6026.
1.4 The method used to specify how data are collected, calculated, or recorded in this standard is not directly related to the accuracy to which the data can be applied in design or other uses, or both. How one applies the results obtained using this standard is beyond its scope.
1.5 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. For specific precaution statements, see Section 8.

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1.1 These test methods provide a qualitative indication of the natural dispersive characteristics of clayey soils.
1.2 These test methods are not applicable for soils with less than 12 % fraction finer than 0.005 mm and with a plasticity index less than or equal to 8.
1.3 The crumb test method has some limitations in its usefulness as an indicator of dispersive clay. A dispersive soil may sometimes give a nondispersive reaction in the crumb test. Soils containing kaolinite with known field dispersion problems have shown nondispersive reactions in the crumb test (1). However, if the crumb test indicates dispersion, the soil is probably dispersive.
1.4 Oven-dried soil should not be used to prepare crumb test specimens, as irreversible changes could occur to the soil pore-water physicochemical properties responsible for dispersion (2).
1.5 The crumb test method, while a good quick indication of dispersive clay, should usually be run in conjunction with a pinhole test and a double hydrometer test, Test Methods D4647 and D4221, respectively.
Note 1--In some cases, the results of the pinhole, crumb, and double-hydrometer test methods may disagree. Crumb test methods are a better indicator of dispersive clays than of nondispersive clays (3).
1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.7 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.

SCOPE
1.1 This test method, when used in conjunction with a test performed by Method D422 on a duplicate soil sample, provides an indication of the natural dispersive characteristics of clay soils (1).  
1.2 This test method is applicable only to soils with a plasticity index greater than 4 as determined in accordance with Method D4318 and more than 12% of the soil fraction finer than 5-[mu]m as determined in accordance with Method D422 (2).  
1.3 This test method is similar to Method D422, except that this method covers the determination of percent of soil particles smaller than 5-[mu]m in diameter in a soil-water suspension without mechanical agitation and to which no dispersing agent has been added.  
1.4 The amount of particles smaller than 5-[mu]m determined by this method compared with the total amount of particles smaller than 5-[mu]m determined by Method D422 is a measure of the dispersive characteristics of the soil.  
1.5 This test method may not identify all dispersive clay soils.  
1.6 This standard does not purport to address the safety problems 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.

SCOPE
1.1 These test methods cover the determination of the bulk density of both peat in its natural state and peat products (Note 1). These test methods consist of defining a volume of peat and determining the mass of that specific volume. The difference in the respective methods is in the procedures employed to determine the peat volume.  Note 1-Test Method D2978 is used for specifying the volume represented by a quantity of loose processed peat or the volume of a peat bale.
1.2 Method A -This method, the core method, covers the determination of the bulk density of an undisturbed core of peat taken with a piston sampler or other suitable core sampler (Sections 6 and 7).  
1.3 Method B -This method, the paraffin wax method, covers the determination of the bulk density of undisturbed clods or irregular pieces of wet peat and compressed peat products (Sections 8 and 9).  
1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This test method covers the determination of the pore volume and the pore volume distributions of soil and rock by the mercury intrusion porosimetry method. The range of apparent diameters of pores for which this test method is applicable is fixed by the operant pressure range of the testing instrument. This range is typically between apparent pore entrance diameters of about 100 [mu]m and 2.5 nm (0.0025 [mu]m). Larger pores must be measured by another method.  
1.2 Mercury intrusion porosimetry is useful only for measuring pores open to the outside of a soil or rock fragment; mercury intrusion porosimetry will not give the volume of any pores completely enclosed by surrounding solids. This test method will give only the volume of intrudable pores that have an apparent diameter corresponding to a pressure within the pressurizing range of the testing instrument.  
1.3 The intrusion process proceeds from the outside of a fragment toward its center. Comparatively large interior pores can exist that have smaller pores as the only means of access. Mercury intrusion porosimetry will incorrectly register the entire volume of these "ink-bottle" pores as having the apparent diameter of the smaller access pores. In a test sample, inter-fragment pores can exist in addition to intra-fragment pores (see Section 3 for definitions). The inter-fragment pores will vary in size and volume depending on the size and shape of the soil or rock fragments and on the manner in which the fragments are packed together. It is possible that some inter-fragment pores can have the same apparent diameter as some intra-fragment pores. When this occurs this test method cannot distinguish between them. Thus, the test method yields an intruded pore volume distribution that is in part dependent upon the packing of multifragment samples. However, most soils and rocks have intra-fragment pores much smaller than the inter-fragment pores. This situation leads to a bi-modal pore size distribution and the distinction between the two classes of pores can then be made (see Figs. 1 and 2).  
1.4 Mercury intrusion may involve the application of high pressures to the sample. This may result in a temporary, or permanent, or temporary and permanent alteration in the pore geometry. Generally, soils and rocks are composed of comparatively strong solids and are less subject to these alterations than certain other materials. However, the possibility remains that the use of this test method may alter the natural pore volume distribution that is being measured.  
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precaution statements, see Section 8.

SCOPE
1.1 This test method presents a direct, qualitative measurement of the dispersibility and consequent colloidal erodibility of clay soils by causing water to flow through a small hole punched in a specimen. This test method is complemented by Test Method D4221.  
1.2 This test method and the criteria for evaluating test data are based upon results of several hundred tests on samples collected from embankments, channels, and other areas where clay soils have eroded or resisted erosion in nature (1).  
1.3 Three alternative procedures for classifying the dispersibility of clay soils are provided as follows:  
1.3.1 Method A and Method C, adapted from Ref (1), classify soils into six categories of dispersiveness as: dispersibility (D1, D2), slight to moderately dispersive (ND4, ND3), and nondispersive (ND2, ND1).  
1.3.2 Method B classifies soils into three categories of dispersiveness as:dispersibility (D), slightly dispersive (SD), and nondispersive (ND).  
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.  
1.5 This standard does not purport to address all of the safety problems, 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.

SCOPE
1.1 This test method describes a procedure for the laboratory determination of the concentration of nitroaromatic and nitramine explosives in soil. The explosives involved in this test method are as follows: HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), RDX (hexahydro-1,3,5-trinitrol-1,3,5-triazine), TNT (2,4,6-trinitrotoluene), TNB (1,3,5 trinitrobenzene), DNB (1,3 dinitrobenzene), tetryl (methyl-2,4,6-trinitrophenylnitramine), and 2,4-DNT (2,4-dinitrotoluene).
1.2 The values stated in SI units are to be regarded as the standard.
1.3 This standard does not purport to address the safety problems 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.

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1.1 This classification is a system for subdividing and assigning nomenclature to peat samples through laboratory tests.  Note 1-A field classification of peat is presently being developed by Subcommittee D18.18.

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1.1 This practice uses a technique of probing to estimate the thickness of surficial peat deposits overlying mineral soil or bedrock. These estimates may be needed for energy, horticultural, or geotechnical purposes.  
1.2 This standard does not purport to address all of the safety problems, 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 .  
1.3 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word "Standard" in the title of this document means only that the document has been approved through the ASTM consensus process.

SCOPE
1.1 This test method covers the quantitative determination of the calcium carbonate (CaCO3) content of soils. It is a gasometric method that utilizes a simple portable apparatus. The test method is quickly performed for soils containing calcium carbonate.  
Note 1-The presence of dolomite CaMg(CO3)2 and reducing minerals such as sulfide and sulfate in the soil will interfere with the determination of the amount of CaCO3 present. Therefore, this test method is an approximate method.
1.2 The values stated in SI units are to be regarded as the 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. For specific precaution statements, see Section 6.

SCOPE
1.1 This test method covers a rapid procedure for squeezing pore water from fine-grained soils for the purpose of determining the amount of soluble salts present in the extracted pore water.  
1.2 This test method was developed for soils having a water content equal to or greater than approximately 14 %, for example, marine soils. An extensive summary of procedures for extracting pore water from soils has been presented by Kriukov and Manheim (1).  
1.3 This test method is not generally applicable for determining the soluble salt content of the pore water extracted from coarse-grained soils, such as clean sands and gravels.  
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.5 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.

SCOPE
1.1 This test method covers a rapid procedure for squeezing pore water from fine-grained soils for the purpose of determining the amount of soluble salts present in the extracted pore water.  
1.2 This test method was developed for soils having a water content equal to or greater than approximately 14 %, for example, marine soils. An extensive summary of procedures for extracting pore water from soils has been presented by Kriukov and Manheim (1).  
1.3 This test method is not generally applicable for determining the soluble salt content of the pore water extracted from coarse-grained soils, such as clean sands and gravels.  
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.5 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.

SIGNIFICANCE AND USE
4.1 This test method can be used to make reliable and reproducible measurements in soil in the range from the detection level to the percent levels of each of seven explosive compounds.  
4.2 This test method does not attempt to quantify the reactivity or mobility of the explosive content, only the concentration of these compounds in the soil.  
4.3 This test method can be used to determine the extent of contamination resulting from the use, misuse, or spillage of explosive compounds. It is useful to determine the effectiveness of clean-up actions at disposal sites, and to determine the environmental impact at explosives disposal, manufacturing, or storage sites.
SCOPE
1.1 This test method describes a procedure for the laboratory determination of the concentration of nitroaromatic and nitramine explosives in soil. The explosives involved in this test method are as follows: HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), RDX (hexahydro-1,3,5-trinitrol-1,3,5-triazine), TNT (2,4,6-trinitrotoluene), TNB (1,3,5 trinitrobenzene), DNB (1,3 dinitrobenzene), tetryl (methyl-2,4,6-trinitrophenylnitramine), and 2,4-DNT (2,4-dinitrotoluene).  
1.2 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.2.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 This standard does not purport to address the safety concerns 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.
WITHDRAWN RATIONALE
This test method describes a procedure for the laboratory determination of the concentration of nitroaromatic and nitramine explosives in soil. The explosives involved in this test method are as follows: HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), RDX (hexahydro-1,3,5-trinitrol-1,3,5-triazine), TNT (2,4,6-trinitrotoluene), TNB (1,3,5 trinitrobenzene), DNB (1,3 dinitrobenzene), tetryl (methyl-2,4,6-trinitrophenylnitramine), and 2,4-DNT (2,4-dinitrotoluene).
Formerly under the jurisdiction of Committee D18 on Soil and Rock, this test method was withdrawn in February 2023. This standard is being withdrawn without replacement due to its limited use by industry.

SCOPE
1.1 This test method covers the determination of distribution ratios of chemical species for site-specific geological media by a batch sorption technique. It is a short-term laboratory method primarily intended for ionic species subject to migration in granular porous material, and the application of the results to long-term field behavior is not known. Distribution ratios for radionuclides in selected geomedia are commonly determined for the purpose of assessing potential migratory behavior at waste repositories. This test method is also applicable to studies of intrusion waters and for parametric studies of the effects of variables and of mechanisms which determine the measured distribution ratios.
1.2 The values stated in acceptable metric units are to be regarded as the standard.
1.3 This standard does not purport to address all of the safety problems, 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.
WITHDRAWN RATIONALE
This test method covers the determination of distribution ratios of chemical species for site-specific geological media by a batch sorption technique. It is a short-term laboratory method primarily intended for ionic species subject to migration in granular porous material, and the application of the results to long-term field behavior is not known. Distribution ratios for radionuclides in selected geomedia are commonly determined for the purpose of assessing potential migratory behavior at waste repositories. This test method is also applicable to studies of intrusion waters and for parametric studies of the effects of variables and of mechanisms which determine the measured distribution ratios.
Formerly under the jurisdiction of Committee D18 on Soil and Rock, this test method was withdrawn in September 2007.