Compacted Clay

GCLs

More material required (resulting in more equipment, more noise, more dust)

Far less material required

Installation time is usually longer

Very rapid installation

Installation is extremely weather-sensitive

Installs in a variety of weather conditions

Difficult to control quality of raw materials

Made with pure, processed bentonite

Difficult to control quality of installation; rigid CQA program required

Pre-manufactured product, rigidly controlled, much less CQA needed

Hydraulic performance is severely compromised by desiccation

Desiccation does not affect hydraulic performance

Cannot withstand differential settlement without cracking

Can undergo settlement with no impact on permeability

Significant freeze/thaw effects

Unaffected by freeze/thaw cycles

Difficult to achieve necessary compaction on soft landfill surface

No compaction required

Heavy construction equipment required

Only light equipment required

Substantial liner construction experience is essential for proper performance

Inexperienced field crews can be trained to install properly

Test pad typically required

No test pad needed

Difficult to repair

Easy to repair using patches

Thickness results in increased space requirements

Very thin and occupies little space

Unpredictable costs

Completely predictable cost

Preferential flow paths likely

No preferential flow paths possible

Roots can open permanent cracks

Swelling bentonite seals around roots

If not available on site, clay soils must be delivered (resulting in excess noise, road deterioration, traffic, air pollution)

One truckload of Bentomat is enough to cover 3,000m².

Additional water must be added during construction

Installed dry, no additional water needed