Whether a mine is situated in a tropical net positive or desert net negative environment, proper planning, design and stewardship is key to maintaining mine site water balance continuity. Maintaining a proper water balance on the mine site requires staff with a thorough understanding of the site’s key variables. This requires understanding the environmental seasonal hydrological possibilities, supported by a solid groundwater model, projecting future site process demands, site water treatment standards, among others.

These inputs, and the data that informs complex site decisions, need to be periodically reviewed and are important during all phases of a mine’s life cycle. Over time, a site’s needs regarding water balance require constant stewardship and updating. Initial hydrological assessments can have limited datasets, and as more climate data becomes available these must be incorporated. The same principles are true for a site’s changing boundaries, process flow demands and disturbed ground.

It is easy to fall into the trap of only looking at the current state of the site and not the variable life stages of the mine, from construction to expansion to closure. Designing for yearly averages, sizing for operations when closure needs are marginally larger, and not being appropriately conservative for sediment control management are some common pitfalls that plague mine operators.

Planning Ahead

A predictive, probabilistic simulation software model, such as GoldSim, can provide a range of likely extreme weather events such as a long drought or major hurricane that could lead to a significant effect on water infrastructure. This data will identify the expected performance of pumps, pits and channels during most years. Planning and designs are often based on the average precipitation in a region. However, a 50- or 100-year precipitation event may lead to a lack of ability to treat or store the water. An extended drought period could be equally devastating to the continuity of operations. These events could result in a plant closure or limited water for nearby communities.

By conducting a thorough stormwater evaluation, water treatment quality can be improved and mine operators can minimize costly repairs or unpermitted discharges. Planning ahead for necessary infrastructure can be as minimal as incorporating a channel or pump with capacity to handle a larger precipitation event. This could prevent plant shutdowns and issues with migration of untreated water off-site.

Mines may start with personnel having in-depth knowledge of site processes and factors unique to that mine; however, understanding can wane over time as personnel turnover results in a smaller group of people with adequate understanding. This can be a factor particularly in instances of increasingly complicated process flow. Not clearly communicating site goals and decisions can often result in wasted money or time throughout the water management process.

Even during situations where there are increased risks to operations, hidden opportunities may be identified that can be leveraged with timely and prudent communication. For example, a thorough stormwater evaluation completed by an integrated team can help with a mine expansion plan. A timely audit of an operational facility can provide detailed recommendations to reduce risk, save money or improve water efficiencies.

Social License to Operate

The concept of social license to operate is well-established, and its impacts go far beyond one specific operation. If a mining operation were to lose social acceptance, it is difficult to recover and be welcomed into other regions for future projects, leading to a negative impact on the reputation of the corporate owner. Upholding environmental standards and minimizing community impacts also helps mine owners maintain a social license to operate. Integrating these practices with corporate environmental, social and governance (ESG) strategies is considered a standard practice. Mine owners can focus on maintaining ESG standards and their social license to operate by hiring local labor, procuring materials from nearby communities, and mitigating noise and dust, in addition to maintaining water quality and discharge commitments.

By asking questions about original mine design intent, water flow and quality parameters, owners can bridge the gap between operators and technical staff for more efficient and effective mine water management systems. Raising these necessary questions unlocks the opportunities for savings and leads to improved water quality. A well-conceived plan mitigates risk involved throughout the process of managing water in a mine.

 

Planning for water scarcity is vital for maintaining a balanced water management approach for mining. Discover how having a thorough understanding of how to uphold water quality can lead to efficient water management strategies and help mine owners avoid operating issues.

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Dan Richards is a project manager at Burns & McDonnell. With more than 15 years of experience, he specializes in program and project management for mining clients, helping them achieve their goals through studies, capital management and operational improvement.