ASTM E2243-13(2019)

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.
Designation: E2243 − 13 (Reapproved 2019)
Standard Guide for
Use of Coal Combustion Products (CCPs) for Surface Mine
Reclamation: Re-contouring and Highwall Reclamation
This standard is issued under the fixed designation E2243; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.5 Regulations governing the use of CCPs vary by state.
The user of this standard guide has the responsibility to
1.1 This guide covers the use of coal combustion products
determine and comply with applicable regulations.
(CCPs) for surface coal mine reclamation applications, as in
beneficial use for reestablishing land contours, highwall 1.6 The values stated in inch-pound units are to be regarded
reclamation, and other reclamation activities requiring fills or as standard. The values given in parentheses are mathematical
soil replacement. The purpose of this standard is to provide conversions to SI units that are provided for information only
guidance on identification of CCPs with appropriate engineer- and are not considered standard.
ing and environmental performance appropriate for surface
1.7 This standard does not purport to address all of the
mine re-contouring and highwall reclamation applications. It
safety concerns, if any, associated with its use. It is the
does not apply to underground mine reclamation applications.
responsibility of the user of this standard to establish appro-
There are many important differences in physical and chemical
priate safety, health, and environmental practices and deter-
characteristics among the various types of CCPs available for
mine the applicability of regulatory limitations prior to use.
use in mine reclamation. CCPs proposed for each project must
1.8 This international standard was developed in accor-
be investigated thoroughly to design CCP placement activities
dance with internationally recognized principles on standard-
to meet the project objectives. This guide provides procedures
ization established in the Decision on Principles for the
for consideration of engineering, economic, and environmental
Development of International Standards, Guides and Recom-
factors in the development of such applications, and should be
mendations issued by the World Trade Organization Technical
used in conjunction with professional judgement. This guide is
Barriers to Trade (TBT) Committee.
not intended to replace the standard of care by which the
adequacy of a given professional service must be judged, nor 2. Referenced Documents
should this guide be applied without consideration of a
2.1 ASTM Standards:
project’s unique aspects.
C188 Test Method for Density of Hydraulic Cement
1.2 The utilization of CCPs under this guide is a component C311 Test Methods for Sampling and Testing Fly Ash or
Natural Pozzolans for Use in Portland-Cement Concrete
of a pollution prevention program; Guide E1609 describes
pollution prevention activities in more detail. Utilization of D75 Practice for Sampling Aggregates
D420 Guide for Site Characterization for Engineering De-
CCPs in this manner conserves land, natural resources, and
energy. sign and Construction Purposes
D422 Test Method for Particle-SizeAnalysis of Soils (With-
1.3 This guide applies to CCPs produced primarily from the
drawn 2016)
combustion of coal.
D653 Terminology Relating to Soil, Rock, and Contained
1.4 The testing, engineering, and construction practices for
Fluids
using CCPs in mine reclamation are similar to generally
D698 Test Methods for Laboratory Compaction Character-
accepted practices for using other materials, including cement
istics of Soil Using Standard Effort (12,400 ft-lbf/ft (600
and soils, in mine reclamation. For guidance on structural fills
kN-m/m ))
to be constructed at mine sites, see applicableASTM guide for
D854 Test Methods for Specific Gravity of Soil Solids by
coal ash structural fills.
Water Pycnometer
1 2
ThisguideisunderthejurisdictionofASTMCommitteeE50onEnvironmental For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Assessment, Risk Management and CorrectiveAction and is the direct responsibil- contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
ity of Subcommittee E50.03 on Beneficial Use. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Sept. 1, 2019. Published September 2019. Originally the ASTM website.
approved in 2002. Last previous edition approved in 2013 as E2243-13. DOI: The last approved version of this historical standard is referenced on
10.1520/E2243-13R19. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2243 − 13 (2019)
D1195 Test Method for Repetitive Static Plate Load Tests of T 290 Determining Water Soluble Sulfate Ion Content in
Soils and Flexible Pavement Components, for Use in Soil
Evaluation and Design of Airport and Highway Pave- T 291 Determining Water Soluble Chloride Ion Content in
ments Soil
D1196 Test Method for Nonrepetitive Static Plate Load
2.3 Other Methods():
Tests of Soils and Flexible Pavement Components, for
EPA Method 1312 Synthetic Precipitation Leaching Proce-
Use in Evaluation and Design of Airport and Highway 5
dure (SPLP) (1)
Pavements
EPAMethod 1320 Multiple Extraction Procedure (MEP) (2)
D1452 Practice for Soil Exploration and Sampling byAuger
EPAMethod Monofill Waste Extraction Procedure (MWEP)
Borings
(3)
D1557 Test Methods for Laboratory Compaction Character-
Synthetic Ground water Leaching Procedure (SGLP) (4)
istics of Soil Using Modified Effort (56,000 ft-lbf/ft
Long-Term Leaching Procedure (LTL) (4)
(2,700 kN-m/m ))
D1586 Test Method for Standard PenetrationTest (SPT) and
3. Terminology
Split-Barrel Sampling of Soils
3.1 Definitions—For definitions related to coal combustion
D1883 Test Method for California Bearing Ratio (CBR) of
products, see Terminology E2201. For definitions related to
Laboratory-Compacted Soils
geotechnical properties, see Terminology D653.
D2166 Test Method for Unconfined Compressive Strength
of Cohesive Soil 3.2 Definitions of Terms Specific to This Standard:
D2216 Test Methods for Laboratory Determination of Water
3.2.1 internal erosion—piping; the progressive removal of
(Moisture) Content of Soil and Rock by Mass soil particles from a mass by percolating water, leading to the
D2435 Test Methods for One-Dimensional Consolidation
development of channels.
Properties of Soils Using Incremental Loading
3.2.2 permeability—the capacity to conduct liquid or gas. It
D3080 Test Method for Direct Shear Test of Soils Under
is measured as the proportionality constant, k, between flow
Consolidated Drained Conditions
velocity, v, and hydraulic gradient, i; v = ki.
D3550 Practice for Thick Wall, Ring-Lined, Split Barrel,
Drive Sampling of Soils
4. Background
D3877 Test Methods for One-Dimensional Expansion,
4.1 Significance and Use—CCPs can be effective materials
Shrinkage, and Uplift Pressure of Soil-Lime Mixtures
3 for use for reclamation of surface mines. Following are key
(Withdrawn 2017)
scenarios in which CCPs may be utilized beneficially in a
D4253 Test Methods for Maximum Index Density and Unit
mined setting:
Weight of Soils Using a Vibratory Table
Structural fill
D4254 Test Methods for Minimum Index Density and Unit
Road construction
Weight of Soils and Calculation of Relative Density
Soil modification or amendment for revegetation (5-9)
D4429 Test Method for CBR (California Bearing Ratio) of
Isolation of acid forming materials (5)
Reduction of acid mine drainage (AMD) (5,10-15)
Soils in Place (Withdrawn 2018)
Highwall mining (16,17)
D4448 Guide for Sampling Ground-Water Monitoring Wells
4.1.1 These options represent most, but not all, scenarios
D4767 Test Method for Consolidated Undrained Triaxial
under which CCPs would be returned to the mine. This guide
Compression Test for Cohesive Soils
discusses issues related to highwall mining and recontouring.
D4972 Test Methods for pH of Soils
Because of the chemical and physical characteristics of CCPs
D5084 Test Methods for Measurement of Hydraulic Con-
and the benefits derived from the use of CCPs in these
ductivity of Saturated Porous Materials Using a Flexible
applications, placement of CCPs in a surface mine setting
Wall Permeameter
qualifies as a beneficial use as defined in Terminology E2201.
D5239 Practice for Characterizing Fly Ash for Use in Soil
4.1.2 CCPs are ideally suited for use in numerous fill
Stabilization
applications. Structural fills and other high-volume fills are
D5851 Guide for Planning and Implementing aWater Moni-
significant opportunities for placement of CCPs in mine
toring Program
situations for reclamation, recontouring, and stabilizing slopes.
E1609 Guide for Development and Implementation of a
These applications are the focus of this guide.
Pollution Prevention Program (Withdrawn 2010)
4.1.3 Any type of CCP may be evaluated for use in mine
E2201 Terminology for Coal Combustion Products
reclamation, even fly ash with high carbon content. Project-
2.2 AASHTO (American Association of State Highway and
specific testing is necessary to ensure that the CCPs selected
Transportation Offıcials) Standards:
for use on a given project will meet the project objectives. The
T 288 Determining Minimum Laboratory Soil Resistivity
use of CCPs can be cost effective because they are available in
T 289 Determining pH of Soil for Use in Corrosion Testing
bulk quantities and reduce expenditures for the manufacture
Available from American Association of State Highway and Transportation
Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001, The boldface numbers in parentheses refer to the list of references at the end of
http://www.transportation.org. this guide.
E2243 − 13 (2019)
and purchase of borrow material, Portland cement, or quick- 4.3.2.1 Fly ash, FGD material, and FBC ash are typically
lime. Large-scale use of CCPs for mine reclamation conserves placed and compacted in a manner similar to noncohesive
landfillspacebyrecyclingavaluableproduct,providedthatthe fine-grained soils. Smooth-drum vibratory rollers or pneumatic
CCPisenvironmentallyandtechnicallysuitableforthedesired tired rollers typically compact these materials most effectively.
use. Although not always, fly ash and FGD material typically
exhibit a measurable moisture-density relationship that can be
4.2 Use of CCPs for Mine Reclamation—E2201 the Stan-
utilized for compaction quality control. To take full advantage
dard on Fly ash, bottom ash, boiler slag, FGD material, and
of the self-hardening properties of some fly ash, FGD material,
FBC ash or combinations thereof can be used for mine
and FBC ash, compaction soon after the addition of water is
reclamation. Each of these materials typically exhibits general
recommended. If hardening or cementation has occurred prior
physicalandchemicalpropertiesthatmustbeconsideredinthe
to compaction, cementitious bonds may need to be disrupted to
design of a mine reclamation project using CCPs. The specific
relocate the grains into a more dense state (18). Strength and
properties of these materials vary from source to source, so
permeability will not be the same for self-hardening materials
environmental and engineering performance testing is recom-
compacted before cementation has occurred as for those
mended for the material(s) or combinations to be used in mine
compactedaftercementationhasoccurred.Compactioncriteria
reclamation projects. Guidance in evaluating the physical,
are usually not specified for FGD material that exhibits
engineering, and chemical properties of CCPs is given in
thixotropic properties.
Sections 6 and 7.
4.3.2.2 Bottom ash is generally placed and compacted in a
4.3 Engineering Properties and Behavior—Depending on
manner similar to noncohesive coarse-grained soils or fine
the mine reclamation application, fly ash, bottom ash, boiler
aggregate. Smooth-drum vibratory rollers typically are most
slag, FGD material, FBC fly ash, FBC bottom ash, or combi-
effective for the compaction of these materials. Bottom ash
nations thereof may have suitable and/or advantageous prop-
may or may not exhibit consistent moisture-density relation-
erties. Each of these materials typically exhibits general
ships. Bottom ash typically compacts best when saturated.
engineering properties that must be considered in engineering
Bottom ash should be compacted to a specified density.
applications. These general engineering properties are dis-
4.3.2.3 Boiler slag is generally placed and compacted in a
cussed in the following subsections; however, it should be
manner similar to noncohesive coarse-grained soils or fine
noted that the specific engineering properties of these materials
aggregate. Smooth-drum vibratory rollers typically are most
can vary greatly from source to source and must be evaluated
effective for the compaction of these materials.As with bottom
foreachmaterial,orcombinationofmaterials,tobeutilizedfor
ash, boiler slag may or may not exhibit consistent moisture-
a structural fill.
density relationships. Boiler slag typically compacts best when
4.3.1 Unit Weight—Many CCPs have relatively low unit
saturated.
weights. This is sometimes referred to as “bulk density” in the
4.3.3 Strength:
literature. The low unit weight of these materials can be
4.3.3.1 Shear Strength—For non-self-hardening fly ash and
advantageous for some structural fill applications. The lighter-
bottom ash, shear strength is derived primarily from internal
weightmaterialwillreducetheloadonweaklayersorzonesof
friction. Typical values for angles of internal friction for
soft foundation soils such as poorly consolidated or landslide-
non-self-hardening fly ash are higher than those for many
pronesoils.Additionally,thelowunitweightofthesematerials
natural soils. These ashes are non-cohesive, and although the
may reduce transportation costs, since less tonnage of material
ash may appear cohesive in a partially saturated state, this
is hauled to fill a given volume. Lower density fills of equal
effect is lost when the material is either completely dried or
internal angle of friction will exert less lateral pressure on
saturated.
retaining structures.
(1) Because of its angular shape, the shear strength of
4.3.1.1 Fly ash is typically lighter than the fill soil it
bottomashistypicallygreaterthanthatofflyashandissimilar
replaces, with unit weight ranging from about 50 to 100 pcf (8
to the shear strength of natural materials of similar gradation.
to 16 kN/m ).
However, friable bottom ash may exhibit lower shear strength
4.3.1.2 Bottom ash is also typically less dense than coarse-
than natural materials of similar gradation.
grained soils of similar gradation, with unit weight ranging
(2) The shear strength of boiler slag may be higher than
from about 70 to 90 pcf (11 to 14 kN/m ).
that of natural materials of similar gradation, owing in part to
4.3.1.3 Boiler slag is typically as heavy as, if not heavier
the typically angular shape and hardness of the particles.
than, natural soils of similar gradation, with unit weight
4.3.3.2 Compressive Strength—Self-hardening CCPs and
ranging from about 90 to 110 pcf (14 to 18 kN/m ).
stabilized FGD material undergo a cementing process that
4.3.1.4 Oxidized and/or fixated FGD materials are also
increases with time. Hydration of dry self-hardening CCPs
relatively lightweight, with unit weights ranging from about 50
commences immediately upon exposure to water and can
to 100 pcf (8 to 16 kN/m ).
cement the CCP particles in a loose state, reducing the
4.3.2 Compaction Characteristics—Most CCPs can be compacted density and strength. High compressive strengths
placed and compacted in a manner very similar to soil and can be achieved if the CCPs are compacted immediately after
aggregate fill materials. In fact, most CCPs exhibit very little incorporation of water. Unconfined compressive strengths
cohesion and are not as sensitive to variations in moisture greater than 2000 psi have been reported for a cementitious
content as are natural soils. ash-water mixture after 248 days (18).
E2243 − 13 (2019)
4.3.4 Consolidation Characteristics—Structural fills con- 4.3.8 Liquefaction and Frost Heave—Although fine-grained
structed of fly ash or FGD material typically exhibit small and noncohesive materials such as fly ash are susceptible to
amounts of time-dependent, postconstruction consolidation. liquefactionandfrostheavewhensaturated,theseproblemsare
This is because excess pore water pressures dissipate relatively readily controlled by design practices that allow for drainage
away from the ash fill. Because of fly ash sensitivity to
rapidly, and thus most of the embankment settlement or
deformation occurs as a result of elastic deformation of the moisture, it is standard practice to design fills to be well
drained. Typically, drainage blankets to provide internal drain-
material rather than by classical consolidation. Most deforma-
tion due to the mass of the fill or structure thereof generally age and serve as a capillary barrier are included at the base of
fills. Also, locating fills in areas where they are not subject to
occurs during construction.
saturation or infiltration by surface water or ground water is
4.3.4.1 Bottom ash and boiler slag are free-draining mate-
normally considered in design. Self-hardening and stabilized
rialsthatcanbecompactedintoarelativelydense,incompress-
fly ash and FGD material are not susceptible to liquefaction.
ible mass. For this reason, structural fills constructed of bottom
Non-stabilized wet FGD material is highly susceptible to frost
ash or boiler slag also typically exhibit small amounts of
heave.
time-dependent, postconstruction consolidation or
4.3.8.1 Well-compacted bottom ash and boiler slag are not
deformation, with the most deformation occurring during
typically susceptible to either liquefaction or frost heave.
construction.
However, some of the finer bottom ash materials may behave
4.3.4.2 Self-hardening fly ash and FGD material typically
quite similarly to fly ash and would require the same consid-
exhibit minimal postconstruction consolidation or deformation
eration for design as fly ash embankments.
because of cementing and solidification of the CCPs.
4.3.9 Specific Gravity—Specific gravity is the ratio of the
4.3.5 Permeability—The values for permeability of CCPs
weightinairofagivenvolumeofsolidsatastatedtemperature
range greatly depending on the type of CCP, the degree of
to the weight in air of an equal volume of distilled water at a
compaction, and other placement variables.
stated temperature. The particle specific gravity of fly ash is
4.3.5.1 The permeability values for non-self-hardening fly
relatively low compared to that of natural materials and
ash are similar to those observed for natural silty soils.
generally ranges from 2.1 to 2.6 (19).
4.3.5.2 Self-hardening fly ash and FGD material are rela-
4.3.10 Grain-Size Distribution—Grain-size distribution de-
tively impermeable, with permeability values similar to those
scribes the proportion of various particle sizes present in a
for natural clays. Self-hardening fly ash and some FGD
material. Fly ash is a uniformly graded product with spherical,
material may be susceptible to cracking in the environment.
very fine-grained particles.
Cracking can produce a conduit for liquids through the placed
4.3.11 Moisture Content—Moisture content is the ratio of
material and change the measured permeability.
the mass of water contained in the pore spaces of soil or rock
4.3.5.3 Bottom ash and boiler slag are typically as perme- material to the solid mass of particles in that material,
able as granular soils of similar gradation.
expressedasapercentage.MostCCPshavealmostnomoisture
whenfirstcollectedafterthecombustionofcoal.Nonstabilized
4.3.6 Erosion Characteristics:
wet FGD material has a high moisture content. Power plant
4.3.6.1 Internal Erosion (Piping)—Non-self-hardening fly
operators sometimes add moisture to facilitate transport and
ash is subject to internal erosion because of its fine-grained,
handling, a process termed conditioning.
noncohesive nature. Internal erosion can be controlled by
4.3.12 Thixotropy—The property of some gels to become
providing adequate surface water controls to minimize infil-
fluids when disturbed by energy events such as vibration. This
tration and by providing internal drainage when warranted.
property may be exhibited by some FGD materials.
(1) Bottom ash and boiler slag typically are well graded
and capable of being compacted to a stable mass. These
4.4 Chemical Properties:
attributes usually preclude any problems arising from internal
4.4.1 Elemental Composition—The major elemental com-
piping of material.
ponents of CCPs are silicon, aluminum, iron, calcium,
(2) Self-hardeningflyashandFGDmaterialareusuallynot
magnesium, sodium, potassium, and sulfur.These elements are
subject to internal erosion.
present in various amounts and combinations dependent pri-
4.3.6.2 Surface Erosion—All CCPs may be eroded by wind
marily on the coal type (bituminous, subbituminous, or lignite)
or water and require use of erosion controls similar to those and type of CCP(coal fly ash, FBC fly ash, FGD material, and
commonly used on earthwork construction projects. Wind
so forth). Trace constituents may include trace elements such
erosion may be controlled by use of wind breaks. Dusting may as arsenic, boron, cadmium, chromium, copper, chlorine,
becontrolledbyadditionofwater,orconditioning,tonon-self-
mercury, manganese, molybdenum, selenium, or zinc (20).
hardening materials. Water erosion can be limited by control-
4.4.2 Phase Associations—The primary elemental constitu-
ling water at the site by using sedimentation, sloping, and
ents of CCPs are present either as amorphous (glassy) phases
run-off controls meeting regulatory requirements. These con-
or crystalline phases. Coal combustion fly ash is typically
trols should be put in place under the supervision of a qualified
70+ % amorphous material. FGD and FBC products are
professional.
primarily crystalline, and the crystalline phases typically in-
clude calcium-based minerals.
4.3.7 Swelling—Some self-hardening CCPs may swell with
time. Paragraph 6.3.8 provides guidance on evaluating the 4.4.3 Pozzolanic Activity—Most fly ash is characterized as
swelling potential of CCPs. pozzolanicbecauseofthepresenceofsiliceousorsiliceousand
E2243 − 13 (2019)
aluminous materials that in themselves possess little or no regulatory determination that the characteristics and manage-
cementitious value but will, in finely divided form and in the ment of the four large-volume fossil fuel combustion waste
presence of moisture, chemically react with calcium hydroxide
streams (that is, fly ash, bottom ash, boiler slag, and flue gas
at ordinary temperatures to form compounds possessing ce-
emission control waste) do not warrant hazardous waste
mentitious properties.
regulation under RCRAand that utilization practices for CCPs
4.4.4 Hygroscopy—Most CCPs are captured and then appear to be safe. In addition, EPA “encourage[d] the utiliza-
handled in conditions that either create or preserve dehydrated tion of coal combustion byproducts and support[ed] State
conditions. Some CCPs have distinctive stable states of hydra-
efforts to promote utilization in an environmentally beneficial
tion.This stable hydration state needs to be considered in some
manner.” In the second phase of the study, EPAfocused on the
applications of CCPs.
byproducts generated from FBC boiler units and the use of
CCPs from FBC and conventional boiler units for mine
4.5 Environmental Considerations:
reclamation, among other things. Following completion of the
4.5.1 Regulatory Framework:
study, EPA issued a regulatory determination that again con-
4.5.1.1 Federal—TheU.S.DepartmentoftheInteriorOffice
cluded that hazardous waste regulation of these combustion
of Surface Mining (OSM) is charged with the responsibility of
residues was not warranted. However, EPA also decided to
ensuring that the national requirements for protecting the
develop national solid waste regulatory standards for CCPs,
environment during coal mining are met and making sure the
including standards for placement of CCPs in surface or
land is reclaimed after it is mined. When the use of CCPs
underground mines, either under RCRA, SMCRA, or a com-
occurs at surface coal mines, state or federal coal-mining
bination of the two programs (65 CFR 32214, May 22, 2000).
regulators are involved to the extent that SMCRA (Surface
4.5.1.2 State and Local—There is considerable variation in
Mining Control and Reclamation Act) requires the mine
state-mandated permitting and other regulatory requirements
operator to ensure that:
for CCP utilization. Some states have specific beneficial use
(1) All toxic materials are treated, buried, and compacted,
policies, while other states have no regulations or guidance
or otherwise disposed of, in a manner designed to prevent
addressing beneficial use.Although the NEPA(National Envi-
contamination of ground or surface water (30 CFR 816/
817.41). ronmental Policy Act) strictly applies only to federally funded
(2) The proposed land use does not present any actual or projects, many states have similar mechanisms for assessing
probable threat of water pollution (30 CFR 816/817.133). the environmental impacts of non-Federal projects. These
(3) The permit application contains a detailed description mechanismsmayrequirestatepermitsthataddressanyorallof
of the measures to be taken during mining and reclamation to
the following issues: wetlands/waterways, National Pollutant
assure the protection of the quality and quantity of surface and
Discharge Elimination System (NPDES) discharge, under-
ground water systems, both on- and off-site, from adverse
ground injection, erosion and sediment control, air quality
effectsoftheminingandreclamationprocess(30CFR780.21).
considerations, and storm water management.
(4) The rights of present users of such water are protected
4.5.2 Water Quality—When planning to use CCPs for mine
(30 CFR 816/817.41).
reclamation, one should consider the potential impacts on
(5) Any disposal of CCPs at mine sites must be in
ground water and surface water to ensure protection of human
accordance with those standards and with applicable solid
health and the environment.
waste disposal requirements (30 CFR 816/817.89).
4.5.2.1 Ground Water—The design and implementation of a
(a) SMCRA gives primary responsibility for regulating
mine reclamation project should consider the potential ground
surface coal mine reclamation to the states, and 24 coal-
water impacts of CCPs to ensure the protection of human
producingstateshavechosentoexercisethatresponsibility.On
health and the environment. Considerable research has been
federallandsandIndianreservations(Navajo,Hopi,andCrow)
conducted to assess and predict the potential impacts of CCP
and in the coal states that have not set up their own regulatory
utilization on ground water quality. An assessment of ground
programs (Tennessee and Washington), OSM issues the coal
water quality impacts should be performed by a qualified
mine permits, conducts the inspections, and handles the en-
professional and should take into account project-specific
forcement responsibilities. As a result of the activities associ-
considerations such as composition of CCPs, the typically
ated with the SMCRA, coal mine operators now reclaim as
limited leachability of CCPs, presence of acid forming mate-
they mine, and mined lands are no longer abandoned without
rials or acid mine drainage, placement of CCPs relative to the
proper reclamation. OSM also collects and distributes funds
ground water table, rates of infiltration, the type of placement
from a tax on coal production to reclaim mined lands that were
used for the CCP, and constituent migration, attenuation in
abandoned without being reclaimed before 1977. OSM has a
ground water, and location of sensitive receptors (that is,
Coal Combustion Residues Management Program that focuses
wells). Where protection of ground water is a special concern,
on providing expert technical information on the use of CCPs
the leaching characteristics of the CCP should be evaluated as
in mine reclamation for the mining industry, regulatory
partoftheassessmentofconstituentmigrationandattenuation.
agencies, and other stakeholders.
Consideration should be given to the leachability of the CCPin
(b) In 1999, U.S. Environmental Protection Agency
(EPA) completed a two-phased study of CCPs for the U.S. the presence ofAMD. Some states may require a groundwater
protection plan be prepared outlining controls that will limit
Congress as required by the Bevill Amendment to RCRA. At
the conclusion of the first phase in 1993, EPA issued a formal potential impact to groundwater.
E2243 − 13 (2019)
4.5.2.2 Surface Water—CCPs may affect surface water bod- reclamation is required under the Surface Mining Law, and the
ies during and after placement activities as a result of erosion reclamation plan is a required part of the permit granted either
and sediment transport. The engineering and construction by the state or OSM.
practices recommended to minimize these effects on surface
5.2 Geologic and Hydrogeologic Investigation—The site
waters include storing the CCPs in stockpiles employing
conditions must be understood. This typically involves a
effective storm water management controls to maximize runoff
review of mine maps and other available information to aid in
and minimize run-on.
understanding the site hydraulic conductivity, ground water
4.5.3 Air Quality—When planning to use CCPs for mine
flow and recharge, water table, and other pertinent information
reclamation, one should consider the potential impacts to air
as determined by a qualified professional.
quality including dusting.
5.3 Environmental Resources—The water supply must be
4.5.3.1 Dust Control—Dusting must be controlled during
considered in evaluating environmental resources at a specific
the transport and handling of CCPs in order to avoid fugitive
site. Additionally, many sensitive environmental resources
dust and to ensure worker safety. Dust control measures
such as wetlands, flood plains, surface water bodies, rare and
routinely used on earthwork projects are effective in minimiz-
endangered species, and cultural resource areas are afforded
ing airborne particulates at CCP storage sites. Typical controls
protection by federal, state, and local regulations and ordi-
include appropriate hauling methods, use of windbreaks, mois-
nances.Appropriate action should be taken to comply with the
tureconditioningoftheCCPs,storageinbinsorsilos,covering
requirements of the regulatory agencies having jurisdiction at
the CCPs with large tarpaulins, wetting or covering exposed
the mine site.
CCP surfaces, and paving or wetting unpaved high-traffic haul
roads with coarse materials.
5.4 Mine Characterization—Two key components of site
4.5.3.2 Radionuclides—Coal and fly ash are not signifi-
characterization for mine reclamation applications are (1)
cantly enriched in radioactive elements or in associated radio-
identification of the mine configuration and geometry and (2)
activity compared to common soils or rocks (21). Certain
evaluation of mine hydrology.
radioactive elements including radium and uranium are known
5.4.1 Mine Configuration—Typical surface-mining methods
to occur naturally in CCPs (15) and other fill materials. The
includeareamining,contourmining,andmountaintopremoval
U.S.DepartmentofEnergyestimatedtheradiumconcentration
mining. Each of these methods requires specific types of
of fly ash to be no more than 3.0 pCi/g (22). Radon emissions
reclamation activities.
from the CCPs are not likely to exceed the naturally occurring
5.4.1.1 Area mining is commonly used in flat or moderately
ambient emissions.
rolling terrain. The overburden is excavated, and the mine is
expanded horizontally. Topsoil and overburden need to be
4.6 Economic Benefits—The use of CCPs for mine reclama-
replaced as the mined area expands. CCPs can be used to
tion can have economic benefits.These benefits are affected by
augment overburden and/or topsoil.
local and regional factors, including production rates, process-
5.4.1.2 Contour mining is typically used in mountainous
ing and handling costs, transportation costs, availability and
terrain.Acut is made into the side of the hill or mountain, and
cost of competing materials, environmental concerns, and the
the mine is expanded by further cuts into the mountain and
experience of materials specifiers, design engineers, purchas-
around the perimeter of the mountain. Highwall areas result
ing agents, contractors, legislators, regulators, and other pro-
from the cuts into the mountain, and these are good candidate
fessionals. CCPs are competing as manufactured materials and
areas for reclaiming with CCPs. CCPs can also be used in
not as waste products, however in the event that CCPs do not
stabilizing the slope of the reclaimed contour mine and in the
meet beneficial use requirements or cannot be utilized, they
preparation of the surface for ground cover required to mini-
should be managed at an appropriate waste facility. Since
mize erosion.
CCPs are produced in the process of manufacturing electricity,
5.4.1.3 Mountaintop removal mining is similar to area
these materials can present an advantage when utilized as raw
products for finished goods. This is primarily due to the low mining, except that the entire top of a mountain is mined.
Topsoil and overburden need to be replaced as the mined area
overheads involved with the material production cost and the
fact that some, but not all coal-fired power plants have expands. CCPs can be used to augment overburden and/or
topsoil.
immediate access to low-cost transportation. The transport of
coal to the power plant can provide an excellent opportunity to 5.4.2 Mine Hydrology—The hydrology of the mine must be
return CCPs to a mine site to aid in mine reclamation projects. understood so that reclamation can be optimized and water
quantity and quality protected. The techniques used to charac-
5. Site Characterization terize mine hydrology are similar to those for a geologic and
hydrogeologic investigation.
5.1 General—The siting and design of a mine reclamation
project requires the identification and resolution of site access 5.5 Environmental Monitoring—Environmental monitoring
and environmental issues and completion of a geologic and provides a means of documenting whether the CCPs used in
hydrogeologic investigation to characterize the subsurface and reclamation activities have impacted the site or surrounding
mine conditions. The degree to which these activities are area. Baseline monitoring should be conducted during site
needed to support the engineering design will vary for each characterization activities and should include the parameters
mine site, depending upon whether the sites are abandoned or (metals and non-metals) attributable to CCPs. At a minimum,
active. In the case of surface coal mines, contemporaneous the monitoring should include the collection of precipitation
E2243 − 13 (2019)
quantity, mine drainage and surrounding surface water quality 6.3.2 Specific Gravity—Test Method D854 is normally used
and quantity, and ground water elevation and quality. Guides for CCPs. For some fly ash and FGD samples, a significant
D5851 and D4448 discuss sampling techniques. All water
portion of the particles may have a density less than water, and
quality samples should be submitted for laboratory analysis of
these will float. Agitation of the slurry may be needed to keep
those chemical parameters deemed appropriate to characterize
the particles in suspension so that the average specific gravity
the baseline water quality of the mine and surrounding site.
canbeobtained.Alternatelyforthisash,self-hardeningflyash,
Monitoring should be conducted at the appropriate frequency
and FGD material, Test Method C188, which uses kerosene as
to ensure that any seasonal variations in water quality and flow
the fluid, may be used.
are characterized. Both the chemical parameters and the
6.3.3 Water Content—Test Method D2216 is normally used
samplingfrequencyshouldbeinaccordancewithrequirements
for CCPs. For self-hardening fly ash and FGD material,
of appropriate governing agencies.
lowering the drying temperature to 140°F (60°C) may be
considered to avoid driving off the water of hydration.
6. Laboratory Test Procedures
6.3.4 Compaction:
6.1 General—Laboratory testing of the proposed CCPs is
6.3.4.1 Fly Ash and FGD Material—Test Methods D698 or
needed to determine and confirm material properties for
D1557 may be used, depending on end use. For dry self-
design. Test results also provide documentation that may be
hardening fly ash and FGD material, the time interval between
requested or required by site owners and regulatory agencies.
wetting and compaction in the laboratory should be similar to
The tests to be conducted should be determined on the basis of
thatanticipatedduringconstructiontoaccountfortheinfluence
site conditions, knowledge of the CCPs, end use, and local
of the rate of hydration on compaction characteristics. Com-
environmental considerations.
paction criteria are not typically developed for FGD material
6.2 Sampling and Handling—Sampling CCPs for testing
that exhibits thixotropic properties, because excessive compac-
purposes should conform to Practice D75 or Test Methods
tion may cause the material to liquefy.
C311, as appropriate. Guide D420 with sample extraction
6.3.4.2 Bottom Ash and Boiler Slag—Test Methods D4253
conducted in accordance with Practice D1452, Test Method
andD4254maybeusedforthedeterminationofmaximumand
D1586, or Practice D3550, as appropriate, should be consid-
minimum density of coarse-grained CCPs that do not exhibit a
ered. Proper laboratory protocols for handling fine-grained
moisture-density relationship.
material should be followed.
6.3.5 Strength—Material strength is defined by shear
6.3 Physical and Engineering Characteristics—Several
strength and compressive strength.
standard test methods developed for soils may be used to
6.3.5.1 Shear Strength—Test Method D3080 can be used to
determine CCPproperties for use in surface mine applications.
determine the shear strength parameters of compacted CCP
These test methods define physical and engineering parameters
specimens under drained conditions. This test is preferred
for use in design and construction control and for comparison
because it models the drained conditions that typically exist in
to other materials. Because of the noncohesive nature of some
astructuralfillconstructedofCCPs.WhenTestMethodD3080
CCPs, extra care in sample handling may be required. These
is used, the method is modified in that the shear box is not to
tests and/or other tests may be warranted depending on the
be filled with water as required by Test Method D3080.
specific mine application for CCPs and should be selected
based on the professional judgement of a qualified scientist or
6.3.5.2 Compressive Strength of Non-Self-Hardening
engineer.
CCPs—Test Method D4767 can be used to predict the as-
6.3.1 Grain-Size Distribution—Test Method D422 is com-
constructed compressive strength of the CCP fill and to design
monly used for determining the grain-size distribution of
forspecificsiteconditions,loadingconditions,andfinalheight.
CCPs. For fly ash and FGD material, a substantial portion of
Specimenstestedforstrengthparametersshallbecompactedto
the material will be finer than the No. 200 sieve, and hydrom-
the densities and water contents required by the project
eteranalyseswillalsoberequired.Distilledwaterisusedinthe
compaction specifications.
hydrometer test, with a deflocculating agent added to prevent
6.3.5.3 Compressive Strength of Self-Hardening Fly Ash
fly ash or FGD material from forming flocs. Self-hardening fly
and FGD Material—Test Method D2166 can be used to
ash(es) and FGD material may require use of alcohol or
determine the unconfined compressive strength at various ages
another nonreactive solution in place of the standard solution.
to evaluate short-term and long-term strength development.
Fly ash often has a relatively uniform particle size, and
6.3.6 Hydraulic Conductivity—Test Method D5084 is com-
precautions against overloading sieves are warranted. Speci-
monly used to determine the hydraulic conductivity of satu-
men loss through dusting can also be a problem. Specific
rated CCPs.
gravity may vary with particle size. Specific gravity values
6.3.7 Compressibility—Samples should be prepared at the
used in hydrometer analyses should be appropriate to the
degree of compaction specified for construction and at the
portion of the sample being tested. Test Method D422 is not
optimum water content determined by the compaction test.
applicable to fly ash with a specific gravity less than 1 unless
This is because fly ash and FGD material tend to lose surface
a nonaqueous solvent is used. Grain-size or particle size
distribution may also be determined by use of dry powder laser stability in the field when compacted at water contents greater
than the optimum for compaction. Special considerations may
diffraction, retention of particles on sieves, or optical particle
counters. be required for wet FGD material which is typically produced
E2243 − 13 (2019)
TABLE 1 Leaching Methods Applicable to Stabilized Materials
at 15 to 20 % above optimum moisture. Test Method D2435
can be used to determine the compressibility of saturated or Leaching Liquid: Leaching
Solution Solid Ratio Duration
unsaturated samples.
MEP (2) Multiple 20:1 24 h/ extraction
6.3.8 Swelling—Test Method D3877 can be used to deter-
solutions
mine the swelling potential of self-hardening fly ash and FGD
(acetic acid,
sulfuric
material. Reactions producing the expansive properties do not
acid, and
commence for a period of more than 30 days after initial ash
nitric acid)
hydration. The test procedures must address this delayed
MWEP (3) Distilled/ 10:1 18 h/ extraction
deionized
reaction. The procedure should be modified to extend the
water or other
wetting and drying cycles to a frequency determined by a
for
qualified design engineer.
specific silt
ASTM D3987 Distilled/ 20:1 24 h
6.4 Chemical Characteristics—Chemical analyses are rou-
deionized wa-
tinely conducted by many CCP producers as a means of ter
SGLP (4)/ Synthetic ground 20:1 18 h/ 30, 60,
determining material variation. The mine reclamation design-
LTL (4) water dictated 90 days
er(s) and other professionals should obtain or evaluate the
by
chemical characteristics of candidate CCPs so they can be site or
distilled/
considered in design, particularly with regard to assessing
deionized wa-
chemical interaction between fill and other materials or struc-
ter
SPLP (1) Sulfuric acid 20:1 18 h
tures. Tests for soluble species, generally accomplished
throughleachingtests,mayalsoberequiredbylocalregulatory
agencies.
6.4.1 Chemical Composition—Test Method C311 is often
7.2.1 Conceptual Site Model—Initially, a conceptual site
used to determine the major chemical constituents of CCP
model should be developed that identifies specific characteris-
samples.
tics with regard to the geology, hydrogeology, and topography
6.4.2 pH—Test Method D4972 or Practice D5239 may be
of the project site, as well as the configuration and discharge
used to determine CCP pH. In assessing the test results,
characteristics of the mine. Pertinent CCP characteristics such
consideration should be given to the possibility that the pH of
as density, pozzolanic or cementitious activity, buffering
the CCP may vary with age, water content, and other condi-
capacity, and permeability should be determined for design
tions.
use. The model should address the changes in CCP properties
6.4.3 Sulfate—Sulfate content as determined from the CCP
thatmayoccurovertime,suchasstrengthgainorloss.Siteand
chemical analysis by Test Method C311 or other method is
CCP characteristics
...