ASTM D6523-22

Standard Guide for Evaluation and Selection of Alternative Daily Covers (ADCs) for Sanitary Landfills

SIGNIFICANCE AND USE
4.1 This guide provides information which the regulator/permit officials, engineers, waste disposal operators, and others will find helpful to (1) understand and distinguish between the many choices available, (2) understand the performance feature considerations for living up to EPA regulations for landfill daily covers, and (3) understand the various requirements and differences for putting these covers into practice at landfills.
SCOPE
1.1 This guide is intended to assist specifiers and end users in assessing the different options available for sanitary landfill daily cover materials described as alternative (non-soil) daily covers (ADCs). Traditional daily cover consists of at least 6 in. (15 cm) of soil spread over the working faces of sanitary landfills. Alternative systems are attractive to landfill operations in order to conserve landfill disposal space, among other reasons.  
1.2 This guide assists in understanding different performance features of broad classifications of ADCs, and determining the extent and degree to which different ADCs are able to “control disease vectors, fires, odors, blowing litter, and scavenging, without presenting a threat to human health and the environment,” as intended by United States Environmental Protection Agency (USEPA) regulations.  
1.3 This guide is not intended to provide cost information regarding the various ADCs. As a standard guide, it does not dictate a protocol for the practice and testing of ADCs, but rather provides valuable information, guidance, and recommendations to interested parties concerning the many options available.  
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.4.1 Exception—Metric units are used in 6.2.9.2.  
1.5 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.

General Information

• Status: Published
• Publication Date: 30-Nov-2022
• ICS: 13.030.40 - Installations and equipment for waste disposal and treatment
• Technical Committee: D35 - Geosynthetics
• Drafting Committee: D35.03 - Permeability and Filtration

Relations

• Refers: ASTM E96/E96M-24 - Standard Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
• Effective Date: 01-Mar-2024
• Refers: ASTM E96/E96M-23 - Standard Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
• Effective Date: 15-Nov-2023
• Refers: ASTM E96/E96M-15 - Standard Test Methods for Water Vapor Transmission of Materials
• Effective Date: 01-May-2015
• Refers: ASTM E96/E96M-14 - Standard Test Methods for Water Vapor Transmission of Materials
• Effective Date: 15-Oct-2014
• Refers: ASTM E96/E96M-13 - Standard Test Methods for Water Vapor Transmission of Materials
• Effective Date: 01-Nov-2013
• Refers: ASTM E96/E96M-12 - Standard Test Methods for Water Vapor Transmission of Materials
• Effective Date: 15-Dec-2012
• Refers: ASTM E96/E96M-10 - Standard Test Methods for Water Vapor Transmission of Materials
• Effective Date: 01-Oct-2010
• Refers: ASTM D4982-95(2007) - Standard Test Methods for Flammability Potential Screening Analysis of Waste
• Effective Date: 01-Feb-2007
• Refers: ASTM E96/E96M-05 - Standard Test Methods for Water Vapor Transmission of Materials
• Effective Date: 01-May-2005
• Refers: ASTM D4982-95 - Standard Test Methods for Flammability Potential Screening Analysis of Waste
• Effective Date: 01-Jan-2001
• Refers: ASTM D4982-95(2001) - Standard Test Methods for Flammability Potential Screening Analysis of Waste
• Effective Date: 01-Jan-2001

Overview

ASTM D6523-22 is the internationally recognized standard guide for the evaluation and selection of alternative daily covers (ADCs) for sanitary landfills. Developed by ASTM International, this guide provides valuable information and recommendations for landfill regulators, permit officials, engineers, and waste management operators working to identify and implement effective non-soil daily cover options. The standard emphasizes key performance criteria for ADCs, including the ability to control disease vectors, fires, odors, blowing litter, and scavenging, in accordance with requirements of the United States Environmental Protection Agency (USEPA) and other environmental bodies. By exploring a broad range of ADC material options, the guide encourages cost-effective strategies that conserve landfill airspace while ensuring robust environmental protection.

Key Topics

Core Areas Addressed by ASTM D6523-22:

• Types of ADCs:
  • Foams: Synthetic materials applied to the landfill working face using specialized foam equipment.
  • Spray-On Slurries: Paper-based slurries are sprayed using hydro-seeding equipment, forming a hardened shell.
  • Geosynthetics:
    • Reusable: Membrane panels placed and removed daily.
    • Nonreusable: Disposable films left in place.
  • Indigenous Materials: Locally available processed waste products (e.g., sludges, shredded tires, foundry sands).
• Performance Features:
  • Disease vector control
  • Odor and air emission management
  • Fire barrier and combustibility
  • Dust and wind-blown litter suppression
  • Water infiltration and leachate management
  • Aesthetic improvements at the landfill working face
• Practical Factors:
  • Methods of application and retrieval
  • Climate and weather adaptability (rain, wind, freezing, heat)
  • Operational considerations and equipment needs
  • Compatibility with site-specific regulatory and environmental guidelines

Applications

Practical Uses for ADCs in Landfills:

• Regulatory Compliance:
  Assists landfill operators in meeting USEPA requirements for daily cover performance, reducing risks associated with disease vectors, fires, and airborne contaminants.
• Space Conservation:
  Use of alternative daily covers can conserve valuable landfill airspace compared to traditional soil covers, extending landfill operational lifespan.
• Cost-effective Waste Management:
  Implementing ADCs may reduce the need for imported soil, minimize operational disruption, and leverage local materials, resulting in logistical and environmental benefits.
• Operational Flexibility:
  Selection from a range of ADC options enables site managers to tailor cover strategies to fit site-specific climatic, waste stream, and regulatory conditions.
• Environmental Stewardship:
  Proper ADC selection and implementation support reduction of leachate generation, minimize odor and gas emissions, and improve the visual impact of landfill operations.

Related Standards

When evaluating and selecting daily cover systems in accordance with ASTM D6523-22, consider referencing additional standards and regulations to ensure comprehensive coverage of all technical requirements:

• ASTM D4982: Test Methods for Flammability Potential Screening Analysis of Waste
• ASTM E96/E96M: Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
• USEPA 40 CFR 258: Technical requirements for municipal solid waste landfills, including daily cover criteria
• California Environmental Protection Agency: Title 27, Section 20680 & 20690: State-specific daily and alternative daily cover regulations

Keywords: alternative daily covers, ADCs, sanitary landfill, landfill daily cover materials, landfill performance, geosynthetics, landfill cover evaluation, waste management standards, ASTM D6523-22, environmental compliance, landfill best practices.

Standards Content (Sample)

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: D6523 −22
Standard Guide for
Evaluation and Selection of Alternative Daily Covers (ADCs)
for Sanitary Landfills
This standard is issued under the fixed designation D6523; 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 2. Referenced Documents
2.1 ASTM Standards:
1.1 This guide is intended to assist specifiers and end users
D4982 Test Methods for Flammability Potential Screening
in assessing the different options available for sanitary landfill
Analysis of Waste
daily cover materials described as alternative (non-soil) daily
E96/E96M Test Methods for Gravimetric Determination of
covers (ADCs).Traditional daily cover consists of at least 6 in.
Water Vapor Transmission Rate of Materials
(15 cm) of soil spread over the working faces of sanitary
2.2 Other Standards:
landfills. Alternative systems are attractive to landfill opera-
Solid Waste Disposal Facility Criteria, USEPA, Technical
tions in order to conserve landfill disposal space, among other
Manual EPA 530-R-93-017, Cover Material
reasons.
Requirements, 40 CFR 258 21, Nov 1993
1.2 This guide assists in understanding different perfor-
“The Use of Alternative Materials for Daily Cover at
mance features of broad classifications of ADCs, and deter-
Municipal Solid Waste Landfills” EPA 600/R-93/172 PB
mining the extent and degree to which differentADCs are able
92-227197, July 1993
to “control disease vectors, fires, odors, blowing litter, and
Alternative Daily Cover Regulations, California Environ-
scavenging, without presenting a threat to human health and
mental Protection Agency, Title 27, Division 2, Subdivi-
the environment,” as intended by United States Environmental
sion 1, Chapter 3, Subchapter 4, Article 2, Section 20680
Protection Agency (USEPA) regulations.
CIWMB Daily Cover and Section 20690 CIWMB Alter-
native Daily Cover
1.3 This guide is not intended to provide cost information
regarding the various ADCs. As a standard guide, it does not
3. Terminology
dictate a protocol for the practice and testing of ADCs, but
3.1 Definitions:
rather provides valuable information, guidance, and recom-
3.1.1 alternative daily cover, n—an alternative to the tradi-
mendations to interested parties concerning the many options
tional 6 in. (15 cm) soil cover required by the USEPA for
available.
landfill working faces to “control disease vectors, fires, odors,
1.4 The values stated in inch-pound units are to be regarded
blowing litter, and scavenging, without presenting a threat to
as standard. The values given in parentheses are mathematical
human health and the environment.”
conversions to SI units that are provided for information only
3.1.2 foam, n—a synthetic material sprayed and combined
and are not considered standard.
with air to form closed-cell air pockets.
1.4.1 Exception—Metric units are used in 6.2.9.2.
3.1.3 gas emissions, n—a release of landfill gas generated
1.5 This international standard was developed in accor-
within the waste mass into the atmosphere through cover
dance with internationally recognized principles on standard-
materials.
ization established in the Decision on Principles for the
3.1.4 geosynthetic, n—a planar product manufactured from
Development of International Standards, Guides and Recom-
polymeric material used with soil, rock, earth, or other geo-
mendations issued by the World Trade Organization Technical
technical engineering related material as an integral part of a
Barriers to Trade (TBT) Committee.
man-made project, structure, or system.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
This guide is under the jurisdiction ofASTM Committee D35 on Geosynthetics contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
and is the direct responsibility of Subcommittee D35.03 on Permeability and Standards volume information, refer to the standard’s Document Summary page on
Filtration. the ASTM website.
Current edition approved Dec. 1, 2022. Published December 2022. Originally AvailablefromU.S.GovernmentPrintingOfficeSuperintendentofDocuments,
ɛ1
approved in 2000. Last previous edition approved in 2014 as D6523 – 00 (2014) . 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
DOI: 10.1520/D6523-22. www.access.gpo.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6523 − 22
3.1.5 indigenous, adj—native to a particular region. 5.4 Indigenous Materials—Indigenous ADCs consist of
various types of locally available waste products for disposal
3.1.6 leachate, n—contaminated water resulting from the
(for example, sludges, ash, shredded tires, shredded green
combination of waste with precipitation.
waste, pulverized construction and demolition debris, automo-
3.1.7 nonreusable, adj—in geosynthetics, a fabric or film
bile recycling fluff, foundry sand, and so forth) placed onto the
intended to be placed once and then disposed of, discarded, or
workingfaceoflandfillsinamannersimilartosoilcover.They
left in place.
often require physical or chemical modification for consistency
3.1.8 reusable, adj—in geosynthetics, a fabric or membrane and workability, and evaluation for the presence of potentially
hazardousconstituents.Processedindigenousmaterialssuchas
material intended to be retrieved and installed more than once
to perform the cover function. treated sludges and asphalt-stabilized soils are available from
manufacturers who are able to provide such products with
3.1.9 sanitary landfill, n—a regulated disposal site for the
consistent properties. Manufacturers should have the necessary
deposition of commercial and household wastes.
supporting data available for review. Unprocessed ADCs can
3.1.10 working face, n—the area of a landfill in which waste
vary significantly with respect to physical and chemical char-
is actively being deposited.
acteristics and composition, depending on the particular
source. In addition, suitability and acceptability are dependent
4. Significance and Use
on site-specific climatic and operational conditions and regu-
latory requirements. Because of the wide variety of processed
4.1 This guide provides information which the regulator/
and unprocessed indigenous materials, only key factors and
permit officials, engineers, waste disposal operators, and others
considerations related to the use and performance of these
will find helpful to (1) understand and distinguish between the
materials can hereby be presented.
many choices available, (2) understand the performance fea-
ture considerations for living up to EPAregulations for landfill
6. Features and Considerations (see Table 1)
daily covers, and (3) understand the various requirements and
differences for putting these covers into practice at landfills.
6.1 Summary—See discussion for clarification.
6.2 Discussion:
5. Classifications of ADCs
6.2.1 Methods of Application:
5.1 Foams—FoamADCs are applied to the working face of
6.2.1.1 Manifold-equipped units apply foam as equipment
sanitary landfills using foam generation and application equip- traverses the working face. Self-propelled units with manifold
ment specifically designed for that particular foam. Both applicator applies foam as the unit backs down the working
hardening and non-hardening foams are currently available. face. Handheld hose-equipped units apply foam as the crew
These foam layers are effectively broken up by the placement walks next to or across the working face, or both.
ofadditionalwastesonthenextoperatingday,andthereforedo 6.2.1.2 Most slurries use truck-mounted or trailer-mounted
not interfere with fluid movement.
standard hydro-seeding equipment with little or no modifica-
tion. It is applied through the spray tower located on the
5.2 Spray-On Slurries—Most slurries are paper-based. The
platform of the hydro-seeding equipment using appropriate
paper-based slurry ADCs are applied to the working face of
nozzles.The use of a handheld hose may be suitable for certain
sanitary landfills using standard hydro-seeding equipment.
applications. In at least one case, a specially designed storage
Certain types of slurries may require some modification of the
unit and mobile applicator is required by the manufacturer.
hydro-seedingequipment.Theslurriesareallowedtohardento
Care must be taken to avoid skimping on the thickness of
form a crust or shell over the working face. This covering is
application.
also broken up by the placement of additional wastes on the
6.2.1.3 At some sites, ancillary equipment (for example,
next operating day.
tow bar, lifting bar, reel, or rollers) are used to facilitate
5.3 Geosynthetics:
placement of geosynthetic panels (both reusable and nonreus-
5.3.1 Reusable—Reusable geosynthetic ADCs consist of
able) and reduce wear and tear. Tires, sandbags, or ballast soil
various types of fabric or plastic membranes that have either are placed along the edges to anchor the panels.
been developed or adapted for use as a daily cover material.
6.2.1.4 The preparation of the working face prior to place-
Panels fabricated from these materials are placed over the
ment of a geosynthetic panel and the care taken in placement
working face at the end of the day, and retrieved prior to the
of the panel can have a significant impact on the effective life
start of the next operating day. Some landfills use special
of a panel. Consequently, operators should ensure that the
mechanized equipment to facilitate the placement and retrieval
working face is properly compacted to provide a smooth
of panels.
surface, and that protruding objects which could damage
5.3.2 Nonreusable—Nonreusable geosynthetic ADCs con- panels are eliminated. In addition, during placement of panels,
measures should be taken to prevent unnecessary stress on the
sist of less durable disposable films or fabrics, intended to be
left in place without retrieval. Special equipment also exists to material and minimize snagging while dragging the panel
across the working face.
facilitate the placement and anchoring of these materials to
cover the working face of landfills. The cover may contain 6.2.1.5 Most indigenous materials may be spread and com-
pro-degradant additives to accelerate degradation within the pacted in the same manner as traditional sands and gravels.
waste to cease the interception of fluids. Dozers and front-end loaders are usually used to spread the
D6523 − 22
TABLE 1 Features and Considerations (see Section 6)
Feature/Consideration Foams Spray-on Slurries Reusable Geosynthetics Nonreusable Geosynthetics Indigenous Materials
Methods of Application Self propelled or towed Truck mounted or trailer Manually, towed with Manually, or spread Most often spread with
equipment with manifold mounted hydro-seeding compactors, or spread w/ specialty unwinder dozers as with traditionally
distribution, or truck equipment w/ spray tower w/ specialty wide panel attached to dozer/ daily cover. Varied.
mounted with handheld and nozzle. deployment equipment. compactor and placing
hose. ballast soil to anchor.
Post-Application
Requirements
a) Equipment Clean-up/ High Low Low if placed Low if placed Low
Maintenance w/ equipment w/ equipment
b) Remove Cover? No No Yes No No
Application in Different Some not recommended Can apply in light rain. Some have no constraints Rain tends to help anchor Generally OK, but sludge
Climates for use during rain. Once cured, can with- while others can absorb cover. and mulch are unsuitably
Others can withstand stand moderate to heavy water, increasing panel applied in rain due to
a) Rain drizzle/light rainfall or light rainfall. weight. excessive run-off.
to moderate rainfall.
b) Wind Can apply in 20 to 40 Can generally apply in Depends on ballast Increase ballast material. Most forms OK but yard
mph winds. Adheres to winds up to 45 mph. mechanism. High winds Small panels, disposable waste and auto fluff are
working face. can pick and destroy. nature reduce impact of excessively effected.
wind damage.
c) Freezing Temp/Snow Can apply under freezing Can apply in freezing Some have no constraints. Shift to different ballast Generally no constraints.
conditions, but equipment temperatures or snow. In others, if moisture has material w/ no moisture Sludge and mulch have
must be protected. Some been absorbed, panels content (for example, some difficulty in snow.
equipment has freeze can freeze, making their crushed glass instead of
protection system. placement and retrieval sand).
more difficult.
d) Hot Weather No constraints No constraints No constraints No constraints Dust generation in many
cases (that is,
unprocessed materials).
Disease Vector Control? Discourages insects and If proper thickness, Can completely cover Can completely cover Must be applied at
(Access by insects, birds from landing; discourages insects and waste so as not to attract; waste so as not to attract. sufficient thickness.
vermin, pathogen rodents from digging. birds from landing; Careful for pathogens in
contact.) rodents from digging. human rehandling.
Fire Control a) Most no, some yes. a) Some no, some yes. a) Yes a) Yes a) Some yes, others no.
a) Combustible? Materials should be
tested per Test Methods
D4982.
b) Barrier to air/gas Low Medium High High Low to High
movement?
Odor and Air Emission Uniform coverage is key. Uniform coverage of suffi- Trap odors and other Trap odors and other Dependent on thickness of
Control? cient thickness is key. emissions while in place; emissions; can be tested application and compac-
Material can be tested release odors and other by Test Methods tion. Dredged materials
by Test Methods emissions when removed; E96/E96M permeation. can themselves be odor-
E96/E96M permeation. can be tested by Test ous. Material can be
Methods E96/E96M tested by Test Methods
permeation. E96/E96M permeation.
Dust Control? Yes Yes Yes Yes Many unprocessed materi-
als generate dust.
Blowing Litter Control? Yes Yes Yes Yes Auto fluff among others
unprocessed materials can
generate litter.
Water Infiltration Control Certain foams can shed Hardening slurries shed Shed rainwater very effec- Shed rainwater effectively Many processed materials
(sheds rainwater) water during moderate water. tively when in place; for several layers of cover. can shed water once com-
rains, once cured. allows infiltration when pacted. Others are too
removed. permeable to shed much
water.
Landfill leachate and gas No interference. No interference. No interference; unless No interference with de- Ash-based wastes,
migration interference? left or buried in place. gradable material dredged soils, clayey soils
(containing a and cementitious foundry
prodegradant); will products can all create
interfere if non-degradable intervening layers.
film.
D6523 − 22
TABLE 1 Continued
Feature/Consideration Foams Spray-on Slurries Reusable Geosynthetics Nonreusable Geosynthetics Indigenous Materials
Life expectancy Varies according to type Some last up to 14 days. Some are 20 to 30 days, Varies from days to Varies. Many processed
of foam. Some last 15 to while others are 10 to 12 months depending on materials will last
20 h while others are from months. additives and conditions. indefinitely.
3 to 7 days.
material. Compaction can be accomplished with single-drum tion of all indigenous materials should be avoided during
rollers, dozer tracks, or loader tires, or combination thereof. periods of significant precipitation.Also, contaminants present
6.2.2 Post-Application Requirements: in unprocessed materials can be leached by infiltrating
6.2.2.1 When equipment is used to apply ADCs there is rainwater,possiblyaffectingthecompositionanddispositionof
cleanup and maintenance. Cleanup often takes place by hosing leachate.As with any engineered facility, proper installation is
with water or compressed air, or both. important for adequate performance.
6.2.2.2 ManyADCs have no other post-application require- 6.2.5 Wind:
ments but are simply broken up by the placement of wastes on 6.2.5.1 Impact of wind during application of foams is
subsequent days. primarily dependent upon the proximity of the discharge
6.2.2.3 Reusable geosynthetic panels are normally removed nozzle to the working face. A
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation: D6523 − 00 (Reapproved 2014) D6523 − 22
Standard Guide for
Evaluation and Selection of Alternative Daily Covers (ADCs)
for Sanitary Landfills
This standard is issued under the fixed designation D6523; 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.
ε NOTE—Units statement was inserted in Section 1.4 editorially in January 2014.
1. Scope
1.1 This guide is intended to assist specifiers and end users in assessing the different options available for sanitary landfill daily
cover materials described as alternative (non-soil) daily covers (ADCs). Traditional daily cover consists of at least 6 in. (15 cm)
of soil spread over the working faces of sanitary landfills. Alternative systems are attractive to landfill operations in order to
conserve landfill disposal space, among other reasons.
1.2 This guide assists in understanding different performance features of broad classifications of ADCs, and determining the extent
and degree to which different ADCs are able to “control disease vectors, fires, odors, blowing litter, and scavenging, without
presenting a threat to human health and the environment,” as intended by United States Environmental Protection Agency
(USEPA) regulations.
1.3 This guide is not intended to provide cost information regarding the various ADCs asADCs. As a standard guide, it does not
dictate a protocol for the practice and testing of ADCs, but rather provides valuable information, guidance, and recommendations
to interested parties concerning the many options available.
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.4.1 Exception—Metric units are used in 6.2.9.2.
1.5 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.
2. Referenced Documents
2.1 ASTM Standards:
D4982 Test Methods for Flammability Potential Screening Analysis of Waste
E96/E96M Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
This guide is under the jurisdiction of ASTM Committee D35 on Geosynthetics and is the direct responsibility of Subcommittee D35.03 on Permeability and Filtration.
Current edition approved Jan. 1, 2014Dec. 1, 2022. Published January 2014December 2022. Originally approved in 2000. Last previous edition approved in 20092014
ɛ1
as D6523–00(2009).D6523 – 00 (2014) . DOI: 10.1520/D6523-00R14E01.10.1520/D6523-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6523 − 22
2.2 Other StandardsStandards:
Solid Waste Disposal Facility Criteria, USEPA, Technical Manual EPA 530-R-93-017, Cover Material Requirements, 40 CFR
258 21, Nov 1993
“The Use of Alternative Materials for Daily Cover at Municipal Solid Waste Landfills” EPA 600/R-93/172 PB 92-22719792-
227197, July 1993
Alternative Daily Cover Regulations, California Environmental Protection Agency, Title 27, Division 2, Subdivision 1, Chapter
3, Subchapter 4, Article 2, Section 20680 CIWMB Daily Cover and Section 20690 CIWMB Alternative Daily Cover
3. Terminology
3.1 alternative daily cover, n—an alternative to the traditional 6-in. (15-cm) soil cover required by the USEPA for landfill working
faces to “control disease vectors, fires, odors, blowing litter, and scavenging, without presenting a threat to human health and the
environment.”
3.1 Definitions:
3.1.1 alternative daily cover, n—an alternative to the traditional 6 in. (15 cm) soil cover required by the USEPA for landfill
working faces to “control disease vectors, fires, odors, blowing litter, and scavenging, without presenting a threat to human health
and the environment.”
3.1.2 foam, n—a synthetic material sprayed and combined with air to form closed-cell air pockets.
3.1.3 gas emissions, n—a release of landfill gas generated within the waste mass into the atmosphere through cover materials.
3.1.4 geosynthetic, n—a planar product manufactured from polymeric material used with soil, rock, earth, or other geotechnical
engineering related material as an integral part of a man-made project, structure, or system.
3.1.5 indigenous, adj—native to a particular region.
3.1.6 leachate, n—contaminated water resulting from the combination of waste with precipitation.
3.1.7 nonreusable, adj—in geosynthetics, a fabric or film intended to be placed once and then disposed of, discarded, or left in
place.
3.1.8 reusable, adj—in geosynthetics, a fabric or membrane material intended to be retrieved and installed more than once to
perform the cover function.
3.1.9 sanitary landfill, n—a regulated disposal site for the deposition of commercial and household wastes.
3.1.10 working face, n—the area of a landfill in which waste is actively being deposited.
3.2 foam, n—a synthetic material sprayed and combined with air to form closed-cell air pockets.
3.3 geosynthetic, n—a planar product manufactured from polymeric material used with soil, rock, earth, or other geotechnical
engineering related material as an integral part of a man-made project, structure, or system.
3.4 indigenous, adj—native to a particular region.
3.5 leachate, n—contaminated water resulting from the combination of waste with precipitation.
3.6 nonreusable, adj—in geosynthetics, a fabric or film intended to be placed once and then disposed of, discarded, or left in place.
Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
www.access.gpo.gov.
D6523 − 22
3.7 reusable, adj—in geosynthetics, a fabric or membrane material intended to be retrieved and installed more than once to
perform the cover function.
3.8 sanitary landfill, n—a regulated disposal site for the deposition of commercial and household wastes.
3.9 working face, n—the area of a landfill in which waste is actively being deposited.
4. Significance and Use
4.1 This guide provides information which the regulator/permit officials, engineers, waste disposal operators, and others will find
helpful to (1) understand and distinguish between the many choices available;available, (2) understand the performance feature
considerations for living up to EPA regulations for landfill daily covers, and (3) understand the various requirements and
differences for putting these covers into practice at landfills.
5. Classifications of ADCs
5.1 Foams—Foam ADCs are applied to the working face of sanitary landfills using foam generation and application equipment
specifically designed for that particular foam. Both hardening and non-hardening foams are currently available. These foam layers
are effectively broken-up broken up by the placement of additional wastes on the next operating day, and therefore doesdo not
interfere with fluid movement.
5.2 Spray-On Slurries—Most slurries are paper-based. The paper-based slurry ADCs are applied to the working face of sanitary
landfills using standard hydro-seeding equipment. Certain types of slurries may require some modification of the hydro-seeding
equipment. The slurries are allowed to harden to form a crust or shell over the working face. This covering is also broken-up broken
up by the placement of additional wastes on the next operating day.
5.3 Geosynthetics:
5.3.1 Reusable—Reusable geosynthetic ADCs consist of various types of fabric or plastic membranes that have either been
developed or adapted for use as a daily cover material. Panels fabricated from these materials are placed over the working face
at the end of the day, and retrieved prior to the start of the next operating day. Some landfills use special mechanized equipment
to facilitate the placement and retrieval of panels.
5.3.2 Nonreusable—Nonreusable geosynthetic ADCs consist of less durable disposable films or fabrics, intended to be left in place
without retrieval. Special equipment also exists to facilitate the placement and anchoring of these materials to cover the working
face of landfills. The cover may contain pro-degradant additives to accelerate degradation within the waste to cease the interception
of fluids.
5.4 Indigenous Materials—Indigenous ADCs consist of various types of locally available waste products for disposal (for
example, sludges, ash, shredded tires, shredded green waste, pulverized construction and demolition debris, automobile recycling
fluff, foundry sand, and so forth) placed onto the working face of landfills in a manner similar to soil cover. They often require
physical or chemical modification for consistency and workability, and evaluation for the presence of potentially hazardous
constituents. Processed indigenous materials such as treated sludges and asphalt-stabilized soils are available from manufacturers
who are able to provide such products with consistent properties. Manufacturers should have the necessary supporting data
available for review. Unprocessed ADCs can vary significantly with respect to physical and chemical characteristics and
composition, depending on the particular source. In addition, suitability and acceptability are dependent on site-specific climatic
and operational conditions and regulatory requirements. Because of the wide variety of processed and unprocessed indigenous
materials, only key factors and considerations related to the use and performance of these materials can hereby be presented.
6. Features and Considerations (see Table 1)
6.1 Summary—See discussion for clarification.
6.2 Discussion:
6.2.1 Methods of Application:
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TABLE 1 Features and Considerations (see Section 6)
Feature/Consideration Foams Spray-on Slurries Reusable Geosynthetics Nonreusable Geosynthetics Indigenous Materials
Methods of Application Self propelled or towed Truck mounted or trailer Manually, towed with Manually, or spread Most often spread with
equipment with manifold mounted hydro-seeding compactors, or spread w/specialty unwinder dozers as with traditionally
distribution, or truck equipment w/spray tower w/specialty wide panel attached to dozer/ daily cover. Varied.
mounted with handheld and nozzle. deployment equipment. compactor and placing
hose. ballast soil to anchor.
Methods of Application Self propelled or towed Truck mounted or trailer Manually, towed with Manually, or spread Most often spread with
equipment with manifold mounted hydro-seeding compactors, or spread w/ specialty unwinder dozers as with traditionally
distribution, or truck equipment w/ spray tower w/ specialty wide panel attached to dozer/ daily cover. Varied.
mounted with handheld and nozzle. deployment equipment. compactor and placing
hose. ballast soil to anchor.
Post-Application
Requirements
a) Equipment Clean-up/ High Low Low if placed Low if placed Low
Maintenance w/equipment w/equipment
a) Equipment Clean-up/ High Low Low if placed Low if placed Low
Maintenance w/ equipment w/ equipment
b) Remove Cover? No No Yes No No
Application in Different Some not recommended Can apply in light rain. Some have no constraints Rain tends to help anchor Generally OK, but sludge
Climates for use during rain. Once cured, can while others can absorb cover. and mulch are unsuitably
Others can withstand withstand moderate to water, increasing panel applied in rain due to
a) Rain drizzle/light rainfall or heavy rainfall. weight. excessive run-off.
light to moderate rainfall.
Application in Different Some not recommended Can apply in light rain. Some have no constraints Rain tends to help anchor Generally OK, but sludge
Climates for use during rain. Once cured, can with- while others can absorb cover. and mulch are unsuitably
Others can withstand stand moderate to heavy water, increasing panel applied in rain due to
a) Rain drizzle/light rainfall or rainfall. weight. excessive run-off.
light to moderate rainfall.
b) Wind Can apply in 20 to 40 Can generally apply in Depends on ballast Increase ballast material. Most forms OK but yard
mph winds. Adheres to winds up to 45 mph. mechanism. High winds Small panels, disposable waste and auto fluff are
working face. can pick and destroy. nature reduce impact of excessively effected.
wind damage.
c) Freezing Temp/Snow Can apply under freezing Can apply in freezing Some have no constraints. Shift to different ballast Generally no Constraints.
conditions, but equipment temperatures or snow. In others, if moisture has material w/no moisture Sludge and mulch have
must be protected. Some been absorbed, panels content (for example, some difficulty in snow.
equipment has freeze can freeze, making their crushed glass instead of
protection system. placement and retrieval sand).
more difficult.
c) Freezing Temp/Snow Can apply under freezing Can apply in freezing Some have no constraints. Shift to different ballast Generally no constraints.
conditions, but equipment temperatures or snow. In others, if moisture has material w/ no moisture Sludge and mulch have
must be protected. Some been absorbed, panels content (for example, some difficulty in snow.
equipment has freeze can freeze, making their crushed glass instead of
protection system. placement and retrieval sand).
more difficult.
d) Hot Weather No constraints No constraints No constraints No constraints Dust generation in many
cases (that is,
unprocessed materials).
Disease Vector Control? Discourages insects and If proper thickness, Can completely cover Can completely cover Must be applied at
(Access by insects, birds from landing; discourages insects and waste so as not to attract; waste so as not to attract. sufficient thickness.
vermin, pathogen rodents from digging. birds from landing; Careful for pathogens in
contact.) rodents from digging. human rehandling.
Fire Control a) Most no, some yes. a) Some no, some yes. a) Yes a) Yes a) Some yes, others no.
a) Combustible? Materials should be
tested per Test Methods
D4982.
b) Barrier to air/gas Low Medium High High Low to High
movement?
Odor and Air Emission Uniform coverage is key. Uniform coverage of suffi- Trap odors and other Trap odors and other Dependent on thickness of
Control? cient thickness is key. emissions while in place; emissions; can be tested application and compac-
Material can be tested release odors and other by Test Methods tion. Dredged materials
by Test Methods emissions when removed; E96/E96M permeation. can themselves be odor-
E96/E96M permeation. can be tested by Test ous. Material can be
Methods E96/E96M tested by Test Methods
permeation. E96/E96M permeation.
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TABLE 1 Continued
Feature/Consideration Foams Spray-on Slurries Reusable Geosynthetics Nonreusable Geosynthetics Indigenous Materials
Dust Control? Yes Yes Yes Yes Many unprocessed
materials generate dust.
Blowing Litter Control? Yes Yes Yes Yes Auto fluff among others
unprocessed materials can
generate litter.
Water Infiltration Control Certain foams can shed Hardening slurries shed Shed rainwater very Shed rainwater effectively Many processed materials
(sheds rainwater) water during moderate water. effectively when in place; for several layers of cover. can shed water once
rains, once cured. allows infiltration when compacted. Others are too
removed. permeable to shed much
water.
Landfill leachate and gas No interference. No interference. No interference; unless No interference with Ash-based wastes,
migration interference? left or buried in place. degradable material dredged soils, clayey soils
(containing a and cementitious foundry
prodegradant); will products can all create
interfere if non-degradable intervening layers.
film.
Life expectancy Varies according to type Some last up to 14 days. Some are 20 to 30 days, Varies from days to Varies. Many processed
of foam. Some last 15 to while others are 10 to 12 months depending on materials will last
20 h while others are months. additives and conditions. indefinitely.
from 3 to 7 days.
Life expectancy Varies according to type Some last up to 14 days. Some are 20 to 30 days, Varies from days to Varies. Many processed
of foam. Some last 15 to while others are 10 to 12 months depending on materials will last
20 h while others are months. additives and conditions. indefinitely.
from 3 to 7 days.
6.2.1.1 Manifold-equipped units apply foam as equipment traverses the working face. Self-propelled units with manifold
applicator applies foam as the unit backs down the working face. Handheld hose-equipped units apply foam as the crew walks next
to or across the working face, or both.
6.2.1.2 Most slurries use truck-mounted or trailer-mounted standard hydro-seeding equipment with little or no modification. It is
applied through the spray tower located on the platform of the hydro-seeding equipment using appropriate nozzles. The use of a
hand-heldhandheld hose may be suitable for certain applications. In at least one case, a specially designed storage unit and mobile
applicator is required by the manufacturer. Care must be taken to avoid skimping on the thickness of application.
6.2.1.3 At some sites, ancillary equipment (for example, tow bar, lifting bar, reel, or rollers) are used to facilitate placement of
geosynthetic panels (both reusable and nonreusable) and reduce wear and tear. Tires, sandbags, or ballast soil are placed along the
edges to anchor the panels.
6.2.1.4 The preparation of the working face prior to placement of a geosynthetic panel and the care taken in placement of the panel
can have a significant impact on the effective life of a panel. Consequently, operators should ensure that the working face is
properly compacted to provide a smooth surface, and that protruding objects which could damage panels are eliminated. In
addition, during placement of panels, measures should be taken to prevent unnecessary stress on the material and minimize
snagging while dragging the panel across the working face.
6.2.1.5 Most indigenous materials may be spread and compacted in the same manner as traditional sands and gravels. Dozers and
front-end loaders are usually used to spread the material. Compaction can be accomplished with single-drum rollers, dozer tracks,
or loader tires, or combination thereof.
6.2.2 Post-Application Requirements:
6.2.2.1 When equipment is used to apply ADCs there is clean-upcleanup and maintenance. Cleanup often takes place by hosing
with water or compressed air, or both.
6.2.2.2 Many ADCs have no other post-application requirements but are simply broken up by the placement of wastes on
subsequent days.
6.2.2.3 Reusable geosynthetic panels are normally removed from the working face prior to the start of the next operating day.
D6523 − 22
Hence, the necessary personnel and equipment have to be available, and sufficient time allowed, for this activity to be performed
prior to the arrival and disposal of waste at the working face. This may require
...