Municipal Solid Waste

• Defined in 40 CFR Part 258.2

• Regulated by 40 CFR Part 258:

RCRA Subtitle D

Landfill DiagramSolid Waste

Liner

Compacted Clay Liner HDPE Liner

Liner

Purposes• To prevent leachate from seeping into

groundwater• To prevent landfill gas from migrating out

of the landfill below grade

Liner

Purposes• To prevent leachate from seeping into

groundwater• To prevent landfill gas from migrating out of

the landfill below grade

Typical Materials• 3-foot layer of compacted soil, underlying• 60-mil high density polyethylene (HDPE)

Leachate Drainage Blanket and Collection System

LeachateDrainage Blanket Collection

Pipes

Leachate Drainage Blanket and Collection System

Purposes• To enhance the effectiveness of the liner by

minimizing leachate head• To protect the liner from puncture

Leachate Drainage Blanket and Collection System

Purposes• To enhance the effectiveness of the liner by

minimizing leachate head• To protect the liner from puncture

Typical Materials• Blanket: 1 foot of sand or gravel, underlying• Collection System: HDPE or PVC piping

Final Cover System

Protective Layer

Vegetation

Low Permeability Layer

FML Liner

Final Cover System

Composed of:

• Low Permeability Layer

• Protective Layer

Low Permeability Layer of Final Cover SystemPurposes• To minimize leachate production by

shedding

precipitation rather than allowing it to

percolate through waste

Low Permeability Layer of Final Cover SystemPurposes• To minimize leachate production by

shedding precipitation rather than allowing it to percolate through waste

• To prevent leachate popouts

Low Permeability Layer of Final Cover SystemPurposes• To minimize leachate production by shedding

precipitation rather than allowing it to

percolate through waste• To prevent leachate popouts• To provide a barrier (along with the protective

layer) between the waste and receptors

Low Permeability Layer of Final Cover System

Purposes• To minimize leachate production by shedding

precipitation rather than allowing it to percolate through waste

• To prevent leachate popouts• To provide a barrier (along with the protective

layer) between the waste and receptors• To prevent uncontrolled emission of landfill

gas into atmosphere through top of landfill

Low Permeability Layer of Final Cover System

Typical Materials• Compacted soil and• 30 or 40-mil polyethylene or PVC flexible

membrane liner (FML)

Protective Layer of Final Cover SystemPurposes• To protect the low permeability layer from

freeze/thaw, desiccation cracking, root penetration and puncture

• To provide a durable, low maintenance surface

Protective Layer of Final Cover System

Typical Materials• Uncompacted soil with• Grass on surface

Gas Monitoring SystemPurposes• To characterize gas production within the

landfill• To detect any methane moving out of the

landfill either below grade or through the final cover system

Groundwater Monitoring System

GroundwaterMonitoring Well

Groundwater Monitoring System

Purpose• To detect any groundwater contamination

caused by the landfill

Surface Water Control System

Purposes• To enhance the effectiveness of the final

cover system in shedding precipitation, and • To prevent surface water contamination

Landfill Operation• Dry Entombment

Attempt to prevent introduction of water or air to the landfill – Minimal degradation.

Landfill Operation

• Dry EntombmentAttempt to prevent introduction of water or air to the landfill – Minimal degradation.

• BioreactorAny liquid (other than leachate) is added in a controlled fashion into the waste to accelerate or enhance the anaerobic (without oxygen) biodegradation of the waste.

Gas Production Graph