Commercial

Pyrite removal (commercial)

Problems

Pyrite

The presence of pyrite in the backfill under the concrete slabs or in the concrete produces sulfuric acid, a substance which causes the bursting of the stone and swelling of the backfill.

Fuel (Oil)

Earth contaminated with fuel that pollutes indoor air and the groundwater.

Symptoms

Pyrite

  • Cracks in the basement and in the garage foundations.
  • Cracks and uprising of the basement and the garage floors.
  • Presence of white powder near the cracks

Oil

  • Fuel odors (fumes) in the air
  • Presence of oil on the surface

Causes

Pyrite

Use of backfill containing pyrite (stone non DB certified)

Oil

Old heating oil tanks buried or leaking.

Solutions

Pyrite

A laboratory test shows if the stone in the backfill has a high swelling potential. If this is the case, you must excavate the backfill and replace with crushed stone – DB certified (without swelling potential).

Oil

The backfill should absolutely be removed.

Work to be performed

Pyrite and/or oil.

  1. Crush the damaged existing concrete
  2. Remove the backfill or any contaminated soil
  3. Spread and compact a new backfill of stone DB certified
  4. Make a new concrete slab