In today’s blog post, I’ll discuss Pit Reconciliation using GEOVIA InSite. A pit balance is commonly used at open pit operations to adjust the recorded output from the pit, which has the benefit of being able to calculate volumes of waste production.
The InSite Material Balance is used to redistribute discrepancies between daily movements and reconciled end of month values.
InSite records all material movements at a mining operation, from the mine sources to the plant, or even beyond to the final product delivered to the customer. However these recorded values contain inaccuracies due to the use of factors (truck / loader), weightometer calibration or human data recording issues. The InSite Material balance adjusts the movement and grade numbers for the month, using a high confidence measurement to over-ride the lower confidence measurements.
A common technique for reconciling month end differences is to “push back from the crusher” using the high confidence plant feed to correct the numbers back to the mine source, but a flaw in the technique is that it only handles ore and won’t provide any information about waste movements – while Pit Reconciliation using InSite Material balance will be able to calculate accurate waste numbers for the month.
A survey is made of the pit, often on a bench basis, to record the growth of the pit void. The difference between the last end of month and the current end of the month represents the volume of material mined. To set this up in InSite, we create an envelope to represent the Pit, and select the movement location type, probably at the block level. A parent child relationship must exist between the location types.
When the Material balance is run, we expand the pit to reveal the bench then adjust the outputs from the bench. Every movement will be proportionally adjusted by the difference between the original value and the pit survey.
The Material balance can be saved and every single haulage movement will have a new “Actual” value to represent how much material was really moved. The difference between the original amount of material moved and the true reconciled volume can be analyzed to provide managers with the information they need to improve their decision making.
Benefits of using Pit Reconciliation:
- Detecting whether trucks are fully loaded
- Faster performance of reconciliation process frees geology and engineering staff to perform other tasks
- Analysis of individual equipment and operator efficiency
- Double-checking contractors are moving stated volumes of material
- Detecting patterns of under-performance
Any open-pit InSite customer is able to use this feature without any extra licensing – all that’s required are some configuration changes and a little training.
Learn more about the InSite Material Balance reconciliation process or watch an InSite video here.
Our previous InSite tips also include:
- InSite Reporting Explained: Mobile, Power BI and Paginated Reports
- How to Control Application Pool Recycling
- InSite Reporting Explained: Dashboards & KPIs
