Process Safety Indicators on Mining – Focus on Geotechnical Asset

For many years, large companies in the industrial sector evaluated safety performance focused on occupational aspects, with indicators based on injuries rates. After the occurrence of major industrial accidents, it was observed that most occupational indicators associated with injuries did not necessarily demonstrate an improvement in the prevention of industrial accidents. Therefore, there was a need to monitor the safety performance of industrial processes safety with specific indicators.

Historically, this monitoring has been carried out in the oil & gas and petrochemical industries, which subsidized international references such as the Process Safety Indicators Guide of Center for Chemical Processes Safety (CCPS) and the standard of the American Petroleum Institute (API 754) Process Safety Performance Indicators for Refining and Petrochemical Industries. The mining industry, due to the absence of specific references, uses these materials as guidelines for the implementation of process safety indicators.

After tailings storage facilities break down on Brumadinho, we percept that mineral sector production chain has characteristics that could result in major accident, which consequences as several as P-36 Platform explosion – Brazil (2001), sugar refinery explosion – Georgia (2008), coal mine accident – China (2014), and others.

On this way, Vale`s have been working daily to identify lesson learning related to Brumadinho, drives the cultural transformation on the company, foment the application of continuous lesson in the management system and reduce risk event of different operational nature.

Due to the specificities of Vale's operations in relation to mining and ore processing when compared to chemical and petrochemical industries, the need was identified to adapt to the concept of process safety events and the adoption of a methodology to identify indicators related to safety of operations

As a result of this adaptation, was elaborated a methodology to identify, record an classification events, resulting on indicators related to operational safety, considering – including – criteria to identification events related to geotechnical assets.

Considering CCPS requirements, assumptions were established that allow for the incorporation of the concept into the management system through a specific definition and well-defined criteria for identifying and classification occurrences, as well as making adaptations into the internal procedures, computerized system for recording occurrences and communication plan for the company.

The definition of the concept to identify process safety events for Vale was not limited to considering “loss of primary containment” of hazardous material, which is normally practiced in industries. The concept was expanded to also consider the unplanned and uncontrolled release of hazardous energy whose consequence could result on damage on health, environmental, property and the community – with loss containment material or not. Such considerations become the trigger for identifying these events and transcend the application of the concept beyond industrial process plants in organizations.

More than definitions customizing, the systematic were organized in to important steps. The first refers to flowchart with three strategic questions that, through the key word, conduct the employee to think about and result, or not, an identification the occurrence as process safety event.

It should be noted that Vale already has a robust system for identifying and dealing with accidents of different sizes, with the new facilities incorporated into the global event management standard. Events that do not fit into the concept are treated with the same rigor and importance as process events.

Answering the three questions as “yes” in the flow, there is the second step where a list of criteria is made available for each level of severity, aligned with the CCPS guidelines for each Tier. With the participation of a multidisciplinary team, the description of the criteria represents the breakdown of guidelines for the reality of Vale's operations.

In this context, specific criteria were established in order to identify events related to geotechnical assets, which are structures such as water storage, tailings and sediment containment dams, mining waste storage facilities, piles of materials, pits and underground works with critical risks to operations.

Professionals with expertise in geotechnical and process safety issues worked on the development of criteria such as “Dam or dike failure with total or partial uncontrolled release of reserved material” as a Tier1 severity event.

The parameters established in the CCPS as well as other documents such as the Global Industry Standard on Tailings Management (GISTM), which is structured into 15 principles that strengthen a holistic view on the management of tailings storage structures, also served as a source of reference. Principle 11 Develop an Organizational Culture that Promotes Learning, Communication and Early Recognition of Problems stands out, which encourages the implementation of lessons learned from the process of internal investigations into incidents and relevant external reports.

In addition to the criteria associated with dams, parameters were developed considering ore piles, pits and slopes, further encompassing the possibility of identifying events in geotechnical assets, making it possible to identify their causes as a lesson to prevent similar accidents.

Therefore, the objective of this work is to present Vale's methodology for identifying process safety events for mining, considering the general context for equipment and operational assets as well as the specific approach for geotechnical assets.

By identifying, recording and handling process safety events, Vale aims to transform the company's organizational culture by adding other actions to current practices that can promote the prevention of serious industrial accidents, bringing visibility to leadership. Through work aimed at promoting the integrity of its facilities, Vale is strengthened to reach another level of safety and operational excellence, becoming a safer and more reliable company, a reference in mining.