CPWM Landfill Design and Operations 2

Question 1

What is the primary purpose of a leachate collection and removal system (LCRS) in a municipal solid waste landfill?

Accepted Answer

To collect and remove contaminated liquid that percolates through waste

Answer

To prevent stormwater from entering the landfill

Answer

To distribute gas evenly throughout the landfill

Answer

To monitor groundwater levels beneath the facility

Question 2

Under RCRA Subtitle D, what minimum slope is typically required for the bottom liner of a municipal solid waste landfill to ensure proper leachate drainage?

Accepted Answer

2%

Answer

1%

Answer

5%

Answer

10%

Question 3

Which type of soil is most commonly specified as a component of composite liner systems because of its low hydraulic conductivity?

Accepted Answer

Compacted clay

Answer

Sandy loam

Answer

Silty sand

Answer

Gravel

Question 4

What is the function of a geomembrane in a landfill liner system?

Accepted Answer

To act as a primary barrier preventing leachate migration

Answer

To provide structural support for heavy equipment

Answer

To promote biodegradation of organic waste

Answer

To filter suspended solids from leachate

Question 5

Daily cover is required at active landfills primarily to:

Accepted Answer

Control odors, vectors, and fire, and reduce litter

Answer

Increase the compaction density of waste

Answer

Accelerate methane gas generation

Answer

Improve leachate quality before collection

Question 6

A landfill operator notices that the leachate collection pipes are draining more slowly than usual. What is the most likely cause?

Accepted Answer

Biological clogging or sedimentation in the drainage layer

Answer

Increased rainfall causing diluted leachate

Answer

Elevated landfill gas pressure suppressing flow

Answer

Geomembrane expansion reducing pipe diameter

Question 7

Which landfill operational practice helps maximize the airspace utilization and structural stability of the waste mass?

Accepted Answer

Compacting waste in 2-foot lifts using a landfill compactor

Answer

Spreading waste in thin lifts without compaction

Answer

Placing waste in large uncontrolled mounds

Answer

Mixing waste randomly to improve settlement