Optimize your grade control system in eight steps

In both open pit and underground mining operations, grade control is essential. For mining businesses to keep correct grade information, they must monitor ore quality while managing a deposit’s grade and variability. Plans for the mine, the allocation of resources, and eventually the mine’s return on investment are all influenced by this.

Geologists are not the only ones in charge of grade control. It includes data gathering, analysis, modelling, and the creation of workable excavation plans, among other phases of the mining value chain. A daily, weekly, or monthly reporting and reconciliation stage may also be included, along with stockpile sampling and checks at strategic locations, such as belt, truck, and face samples.

An effective grade control system can reduce dilution, maximise recovery, enhance the reconciliation of actual and projected production, create consistency in operations, guarantee knowledge continuity, and foster greater cooperation among geology, planning, and production. Effective grade control, on the other hand, can lower a mining operation’s total productivity and profitability.

There are some fundamental best practices to maximise efficiency and get the most out of your grade control system, even if each site defines grade control differently through duties and procedures unique to that operation.

Establish a consistent, repeatable and customisable framework 

The secret to a successful grade control system is careful planning. In the early phases of the grade control planning process, put up detailed procedures and predetermined parameters. This establishes expectations for results and helps guarantee consistency in procedures. Your framework can be modified to accommodate your operation’s evolving needs as you proceed through later stages of the mining cycle.

Document your workflows 

Make written, step-by-step method documents after you have built your framework. In addition to facilitating internal alignment and enabling you to validate your processes and criteria with other departments, this also aids in giving grade control staff training and reference materials.

As the workflow is improved and improvements are made, be careful to update your documentation frequently. This will significantly aid in the transfer of knowledge to new hires that need onboarding as a result of retirements and resignations.

Validate your data 

The quality of the data that enters your grade control system determines its effectiveness. Make sure your data is reliable and legitimate before adding it to your grade control system to maintain proper data hygiene. To guarantee accurate and trustworthy sample data, this involves carrying out an efficient quality assurance/quality control (QA/QC) procedure.

Depending on the platform you use, this can occasionally be done within the database itself when the data is entered. The best outcomes will come from automating the procedure to cut down on errors and save time.

Enforce consistent interpretations across your team 

When interpreting grade information, consistency is crucial. For instance, even minor changes to the guidelines and standards used to define dig sites could have significant repercussions, thereby increasing ore loss and dilution.

To make interpretation easier, grade information should instead be categorised and coloured based on predetermined ranges and cut-offs. Establishing precise norms and regulations for defining interpolation domains and dig limitations is necessary to achieve this. This procedure can be automated, depending on the software your grade control system uses.

Work from a single source of truth 

All team members and departments do not always have easy access to the most recent grade control data. Instead, it is kept on a local hard disc in a static document. Furthermore, the document loses its relevance as soon as the original is altered, even if it is distributed to the appropriate team members.

To guarantee that every team member always has real-time access to pertinent data, digital platforms are now available that can ingest, integrate, or index data. Decision-making is enhanced and expedited by this visibility, which also helps with internal validation and alignment.

Facilitate collaboration 

Making the right decisions requires cooperation between departments and team members in addition to a single source of truth. All team members, whether or not they are on the same team, should have open channels of communication. Collaboration tools that are integrated into some sophisticated company platforms will make this process simple. Even in the absence of this, it’s critical to dismantle departmental silos and motivate team members to examine documents and offer candid, open comments.

Centralise and structure your data storage 

Although it might seem simple, be sure to set up efficient file name conventions and structured data storage guidelines. Nothing is worse than data that cannot be located due to a disorganised file structure or an unintelligible file name. Establishing appropriate naming conventions will guarantee uniformity, boost data accessibility, and increase searchability. Additionally, it facilitates automation, which can save you and your business a great deal of time.

Don’t neglect reconciliation 

Lastly, any activity must include reconciliation. Compare your actual production with the grade control system’s expected results on a regular basis (e.g., weekly or monthly). You can comfortably proceed with your mine plan if there are no problems. To improve future grade and tonnage estimates, adjust your workflows, parameters, and settings if there are disparities. By doing material reconciliation on a regular basis, you can keep your business profitable and on track while also adjusting to any changes that may arise over the course of mining.

Author: Stephanie Philips, GEOVIA Industry Process Consultant Senior Manager, Dassault Systèmes (an AusIMM Industry Partner).