Using a variety of geophysical survey methods, GeoModel, Inc. can locate and delineate the extent of a landfill up to 50 feet deep.
Our instruments can detect and determine the size and extent of:
- Burial trenches
- Landfill cells and waste pits
- Buried metal (i.e. steel drums)
- Inorganic or salt water (brine) plumes
One of the methods that GeoModel, Inc. uses to locate buried landfill cells and burial trenches is an electromagnetic conductivity survey, also called terrain conductivity or EM survey. Electromagnetic conductivity can measure both the variations in ground conductivity and the amount of buried metal in a landfill or burial trench.
Ground conductivity in landfill cells and burial trenches can decrease in areas that contain non-metallic construction debris, such as wall board or non-reinforced concrete, or general paper products. Ground conductivity in landfill cells and burial trenches can increase due to concrete reinforced with rebar or wire mesh, metal paint cans, steel drums, or other metallic objects, or due to high total dissolved solids from acids or salts in the soils or groundwater.
EM surveys can be useful for delineation of both the landfill debris and of any conductive or inorganic groundwater plumes emanating from the landfill or burial trench and migrating downgradient and possibly offsite from the landfill.
Results from an electromagnetic conductivity (EM) survey for landfill detection is shown below. The orange and red colors represent buried metal and high conductivity debris in the landfill cells and trenches. The blue and green colors represent lower conductivity areas outside of the landfill cells and trenches.
GeoModel, Inc. also uses ground penetrating radar (GPR) for locating landfills, waste pits, and burial trenches. GPR utilizes an antenna (or transducer) to introduce signals into the ground that reflect from buried landfill materials and create an image of the subsurface onto a field computer. An example of a GPR profile showing two landfill burial trenches is shown below. GPR images can assist in the determination of not only the extent, but the depth of landfill cells and burial trenches.
Click on an image for a larger view.