Case Study: 3D Mobile Scanning used in Reserve Calculation and Mineable Modeling

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“He inquired of Firmatek, LLC to see if there was a way to quantify his reserves and help him establish a profitable plan for excavating and updating the operation as the new mine progressed.”

In April of 2010 Firmatek performed services for a client who’d purchased a piece of property with the intention of mining it out.  By drilling core samples throughout the 500+ acre property it was determined that beneath a rolling layer of overburden lay reserves of sand and gravel.  The owner had geotechnical core sample data but no useful way of determining how much sand and gravel he had or how it was distributed.  He had rough GPS coordinates from a handheld device for the locations of the drill holes but was lacking accurate elevations.  He inquired of Firmatek, LLC to see if there was a way to quantify his reserves and help him establish a profitable plan for excavating and updating the operation as the new mine progressed.

The first step in our process was to model the topography with data from a mobile scanner.  With the property cleared enough for navigation with a 4WD vehicle the laser survey was complete in a matter of hours.  A 3D point cloud was created of the landscape, complete with fields, trees, fences, roads, and buildings.  Post-processing involved removing the noise and marking the perimeter of the mine site.  This left us with a clean topography making the changing slopes visible.

The next step was to take the GPS coodinates of the sample drill holes and attach them to the topography so that the collar (or top) of each drill hole was at it’s proper elevation on the surface.  This being done, we now had all the information we needed to calculate the reserves by fusing the surface with geotechnical core sample data to develop a three-dimensional model of the subsurface geologic reserves. This model was used to estimate the boundaries and calculate the volume of usable reserves on the property.

These calculations were helpful, but further discussions revealed that the client had a more complex need.  The 3D models revealed that although good mineable material was distibuted throughout the property, certain areas required the excavation of too much overburden to make the recovery of thinner layers of the choice material economically logical.  What was needed was a way to isolate the portions of the property that failed to meet a chosen criteria.  To meet this need, the property was sectioned into grids with a 50′ spacing and areas where a 3:1 ratio (of overburden to sand and gravel) was exceeded were rejected and called non-mineable. Using this information the recovery rate for mined areas is increased substantially and those areas that could have been money-suckers are avoided.

Although calculations for reserves and mine modeling have been used in industry for years, the introduction of mobile mapping has made the process faster and much more accurate.  The client was very satisfied.  He now has a better strategy to make money as well as a base model which will allow him to accurately track and model his operation as the excavation progresses.

Firmatek, LLC gets excited about providing its clients with greater opportunities for success through technology and a trustworthy service relationship.