GeoSynthetic Clay Liners - Solid Waste Association of North America

SWANA/A&WMA’s
Third Annual Landfill Operator’s Training
Geosynthetics in Landfills
February 13, 2013
Geosynthetics
Products
Applications
Current Lining Requirements
Tips
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Geosynthetics
polymeric products used to solve civil engineering
problems. This includes eight main product
categories: geotextiles, geogrids, geonets,
geomembranes, geosynthetic clay liners, geofoam,
geocells and geocomposites.
planar product manufactured from a polymeric
material that is used with soil, rock, or other
geotechnical-related material as an integral part of a
civil engineering project, structure, or system.
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PRODUCTS
Products
Geomembranes
Geomembranes are the most
widely used products for solid
waste containment (such as
landfill liners), mining, and water
containment applications. GeoSynthetic
Clay Liners
Geosynthetic clay liners (GCLs) combine
geosynthetics with sodium bentonite clay
to form a highly impermeable barrier that
often replaces thick layers of expensive
compacted clay. Geonets and
Geocomposites
GSE offers a broad range of quality
geonet and geocomposite drainage
liners designed to complement or
replace sand, stone and gravel.
Geotextiles
GSE produces the most uniform,
consistent and versatile nonwoven
geotextile products on the market.
Our products are available in many
weights and thicknesses to meet your
specific project requirements.
Concrete Protection
Protect your investments
with GSE StudLiner, a line of high
density polyethylene (HDPE) concrete
protection products with studs on one
side that lock the liner into the surface to
prolong the life of the concrete.
Specialty Products
GSE has developed specialty products
to provide for unique solutions. Whether
it is for environmental, aquaculture, civil,
tunnel or other demanding applications,
GSE products are easy to install and
built to last.
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Geomembranes - Barrier
Less permeable than clay (10-14cm/s v 10-7cm/s)
Space savings v clay
Proven performance >30 years
Easier/Quicker to install than clay
especially on slopes
Consistent MQA & CQA
2 - 10 acres per truck
20mil – 100mil
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Geosynthetic Clay Liners - Barrier
Space Savings - Replaces 1’ – 2’ of clay
Less permeable than clay (10-9cm/s v 10-7cm/s)
Easier/Quicker to install than clay liners
especially on slopes
Consistent MQA & CQA
1 acre per truck
1lb/sf of bentonite
3oz/sy – 6oz/sy geotextiles
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Geonets & Geocomposites – Liquid Transmission
Equal to 12” sand drainage
Space savings v sand/aggregate
Proven performance >30 years
Easier/Quicker to install than sand/aggregate
Especially on slopes
Consistent MQA & CQA
1.5 - 3 acres per truck
160mil – 300+mil
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Geotextiles – Filtration, Cushion, Separation
Replaces graded granular filter
Space savings v sand
Proven performance >30 years
Easier/Quicker to install than sand
especially on slopes
Consistent MQA & CQA
2 - 15 acres per truck
4oz/sy – 32oz/sy
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APPLICATIONS
Power
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Mining
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Water/Waste Water Containment
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Other Applications
Agriculture
Civil
Industrial
Floating Covers
Superfund Remediation
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Waste Containment
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Waste Containment Applications
Landfill Base Liners
Landfill Closures
Leachate Collection
Temporary Covers
Leachate Recirculation
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Waste Containment – Base Liner
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Waste Containment – Leachate Collection
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Waste Containment - Closures
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CURRENT
LINING
REQUIREMENTS
Current Lining Requirements in the USA
Resource, Conservation and Recovery Act (RCRA)
guidelines for waste containment:
Subtitle C - Hazardous Waste Liner Systems
Subtitle C - Hazardous Waste Cover Systems
Subtitle D - Nonhazardous Waste Liner Systems
Subtitle D - Nonhazardous Waste Cover Systems
Federal regulations set minimum technology guidance
(MTG) for the permitting agency (state regulators) to
follow
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Subtitle C Liner System
Leachate Removal System
(i.e. perforated pipe network)
Solid Waste
Filter Layer
 12”
 12”
Permeability 1x10-2 cm/sec
Leachate Collection
Permeability 1x10-2 cm/sec
Primary Geomembrane  30 mils
if HDPE then  60 mils
Leak Detection
Secondary Geomembrane  30 mils
if HDPE then  60 mils
 24”
Permeability 1x10-7 cm/sec
Compacted Clay Liner (CCL)
or approved alternate
Soil Subgrade
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Subtitle C Cover System
 24”
Top Soil
Filter Layer
 12”
 24”
Permeability 1x10-2 cm/sec
Permeability
k  bottom liner  1x10-5 cm/sec
Drainage Layer (or geosynthetic drainage
Geomembrane  20 mils
if HDPE,  40 mils is most common
Compacted Clay Liner (CCL)
or approved alternate
Solid Waste
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Subtitle D Liner System
Solid Waste
Leachate Removal System
(i.e. perforated pipe network)
Filter Layer
 12”
Permeability 1x10-2 cm/sec
Leachate Collection
Geomembrane  30 mils
if HDPE then  60 mils
 24”
Permeability 1x10-7 cm/sec
Compacted Clay Liner (CCL)
or approved alternate
Soil Subgrade
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Subtitle D Cover System
 6”
 18”
Top Soil
Permeability
k  bottom liner  1x10-5 cm/sec
Geomembrane  20 mils
if HDPE,  40 mils is most common
Compacted Clay Liner (CCL)
or approved alternate
Gas Vent (if necessary)
Solid Waste
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Average Primary Leakage Rates
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4 THINGS YOU
SHOULD DO!
4 Things You Should Do
• Subgrade evaluation: gas generation, water table movement,
subsurface uplifting pressures
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Geomembrane Whales
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4 Things You Should Do
• Subgrade evaluation: gas generation, water table movement,
subsurface uplifting pressures
• Approved installation subcontractor (IAGI – International
Association of Geosynthetic Installers) and Certified CQA
(Construction Quality Assurance) staff
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Repairs and Repairs of Repairs…
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4 Things You Should Do
• Subgrade evaluation: gas generation, water table movement,
subsurface uplifting pressures
• Approved installation subcontractor (IAGI – International
Association of Geosynthetic Installers) and Certified CQA
(Construction Quality Assurance) staff
• Soil/Cover Placement is critical and the source of ~ 2/3 of the
problems
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Cover Soil Placement – not so good
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Cover Soil Placement – great
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4 Things You Should Do
• Subgrade evaluation: gas generation, water table movement,
subsurface uplifting pressures
• Approved installation subcontractor (IAGI – International
Association of Geosynthetic Installers) and Certified CQA
(Construction Quality Assurance) staff
• Soil/Cover Placement is critical and the source of ~ 2/3 of the
problems
• Do post installation liner integrity testing (leak location)
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GSE Leak Location Liner
Leak Location Liner has
historically been used in
applications where leakage is
critical. It has also enjoyed great
success where standard liners
have previously failed.
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GSE Leak Location Liner
Exposed
• Repeat testing as needed
Soil Covered
• Dipole test method
Testing
• Sweep area with wand
• Audible tone and spark
• Mark damage for repair
Summary
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•
•
•
Does not require water
Slopes can be tested
Fast, easy & accurate
Performed by liner field crew
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Final Thought
Savings
Space
Undercut
Installation time
Natural materials
Truck traffic
Improved Performance
Lower permeability
Consistent MQA
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