"PASSION FOR PRECISION"

© 2019 Pretorius Group of Companies 

OUR SERVICES

EUGENE PRETORIUS AND ASSOCIATES (EPA)
 

We have a reputation of delivering services on time, within budget and with an excellent safety record, underpinned by the commitment by Pretorius Group of Companies leadership and teams to service excellence.

Available Technology

Mine and Engineering Survey Services

 

​EPA survey is flexible to offer mine and engineering services that suites the Client’s requirements. These survey services range from:

  • Providing a Mine Surveyor on site

  • Pit alignment (i.e. staking out of cut lines)

  • Survey of overburden and pit voids for quantity determination

  • Establishment of reinstatement levels for spoil grade as detailed in the EMPR (Subject to the availability of a Rehabilitation Model)

  • Survey of rehabilitation status plans and submission of these plans

  • Survey of surface features and infrastructure for updating of mine plans

  • Updating mine plans as required in Chapter 17 of Mine Health and Safety Act no 29 of 1996

  • ROM and product stockpile survey

  • Surveying and quantifying material handling quantities

  • Staking out of blast patterns

  • Underground vent and rescue plans

  • Underground alignment

  • Calculation of opencast/underground volumes and reporting

  • Topographical surveys

  • Aerial surveys

  • Setting out of engineering Work

  • Setting out of exploration Boreholes

  • Draughting of plans (i.e. mine plans, general working plans, risk assessment plans and traffic management plans)

  • EPA will be responsible for Mine Survey in Terms of Mine Health and Safety Act No. 29 of 1996 (including retention of data, attending to mine plan inspections, application for exemptions).

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Geospatial Services

LiDAR Services

 

Volumetric surveys of stock yard and mine dumps:

 

Method: GPS RTK survey and a Trimble MX2 mobile mapper mounted on an LDV. The system collects up to 72 000 points per second.

 

Engineering surveys of road and rail:

 

Method: Total station, electronic level and Teledyne Optech Lynx mobile mapper mounted on an LDV. The system collects up to 1 000 000 points per second.

 

Engineering survey of industrial plants:

Method: Total station and static laser scanner. Setting out and alignment using a total station.

 

RPAS (Drone) Services

EPA has a RPAS Operators Certificate (ROC) issued by the SACAA. This means EPA can legally fly RPAS (Drones) and offer services to its clients.

Orthophoto (Photo Map)

 

Method: GPS RTK control survey and aerial photo acquisition using RTK/PPK enabled RPAS (drones).

 

Digital Terrain Model (DTM)

Method: Processing of flight data to extract a ground model. Accuracy is accessed against surveyed check points. The DTM is filtered to remove above ground features.

 

Plots and Plans

Line mapping from orthophoto and RTK GPS surveys.

Contour generation.

Prospecting and mining right application plans.

 

Satellite Image Services

Small scale mapping

Line mapping (digitizing) of roads and buildings from archive satellite images.

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Aviation/RPAS Services

 

EPA procured aerial imaging Remotely Piloted Aircraft Systems to further expand on our capabilities as a complete survey solutions company. These powerful tools allow for unprecedented overview of operations. These devices are deployed and operated safely minimizing risk and producing fast reliable results. Our team specialize in data handling procedures and processing techniques to optimize data quality and speed of delivery.

Aerial photography offers insight for managers, farmers and production teams where conventional survey is not able to produce the level of detail visible from photography. By combining aerial photography with conventional survey, we can produce superimposed plans with vital survey information draped over an aerial photo. This process makes plans easier to understand and very little interpretation is needed to convey information. By having regular up to date photographs, plans can be compared and updated as operations progress. EPA employs 2 types of RPAS:

 

RTK capable Remotely Piloted Aircraft (RPAS)

The RTK RPAS has the capability of interfacing with a static base station sending real-time differential corrections to the device greatly increasing the accuracy of the produced Digital Surface Model. Combined with sufficient and carefully planned ground control markers the resulting data is comparable in accuracy to conventional survey GPS survey methods in areas clear of vegetation. By utilizing the skills obtained from years of LiDAR processing techniques EPA is able to effectively manage this data and produce valuable and accurate data.

Standalone Remotely Piloted Aircraft (RPAS)

This RPAS operates independently from any conventional survey equipment and relies heavily on correctly planned and placed ground control markers. These markers play a critical role in the final deliverable accuracy achievable. This RPAS is designed and designated primarily for ortho-image production and overview DSM creation. This resulting data can be used for plan updates, progress monitoring and data presentation purposes.

The EPA aviation services can delivers the following:​

  • General Surface Plans

  • Blasting Radius Plans

  • Quarry Updates

  • Pit Updates

  • OGL Surveys

  • Heritage Site Surveys

  • Construction Progress

  • Precision Agricultural Information (NDVI index)

  • Rural Area Development Plans

  • High resolution printed photographs

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Geological Services

EPA employs a committed team of geological personnel including a full-time geologist, grade controller and geotechnical assistants. The geological team are well suited and trained to fulfil the needs of its respective clients. The team has over 40 years of experience in the coal mining industry and are transitioning to service other commodity clients too.

 

The geological services include:

  • Exploration management (Geological drilling and logging)

  • Geophysical wireline services

  • Geophysical magnetometer surveys

  • In-pit grade controlling

  • Stockpile management and quality assurance

  • Geological database management

  • Geological 3D modelling

  • Resource and reserve estimations

  • Competent Persons Report

 

The geological services department does employ two (2) Robertsons Geophysical probes fitted onto 2 LDV’s. The geophysical probes consist of a Long Spaced Density, High Resolution Density and Natural Gamma Sonde with a built in caliper arm to determine sidewall formation competencies. The data of the geophysical probes are interpreted by the geologist to determine the footwall and hanging wall of an ore body or roof and floor contacts of coal seams.

 

A Ceasium-vapour Magnetometer is used to collect anomalous magnetic data, crucial in determining dolerite dyke and sill positioning.

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