The Molybdenum Abatement Plant (PAMo) has been in operation for seventeen years. It was designed and built by Codelco's Vice Presidency of Projects (VP) in 2007. It currently operates under the administration of the Dams, Tailings and Water Resources Management of the El Teniente Division.

Gravity-fed, so its energy consumption is minimal, the plant treats clear water from the Carén Reservoir, in the commune of Alhué, Metropolitan Region, to then be discharged into the Carén and Alhué estuaries.

Its process plays an essential role in reducing molybdenum and regulating the pH (degree of acidity) of the water, ensuring compliance with the RILes (Liquid Industrial Waste) standard. In 2023 alone, 24 million cubic meters of water were treated at the facilities.

Today, the facility stands out as an industry leader, having achieved ISO 50001 certification. This achievement represents a commitment to efficient energy management and rigorous compliance with all applicable legislative and regulatory requirements.

Andrés Campos, Head of Tailings Operations at El Teniente, explained that “five years ago, within the framework of energy efficiency, not only the process and the service provider were certified, but also the plant as a whole. Our operations are subject to constant regulation and monitoring, both internal and external.”

Germán Sandoval, Sustainability and External Affairs Manager, highlighted that “the Molybdenum Plant is an innovation. Since its inception, it has become an absolutely unprecedented contribution to the Division. With its workers, we have generated an increasingly safe and sustainable process.”

Efficiency and safety in the process

Thanks to the copper company's commitment, the PAMo plant complies with the regulations described in Supreme Decree No. 90 for molybdenum, which limits the concentration to a maximum of 1.0 ppm (particles per million) in the discharged water and a pH between 6 and 8.5, on a scale ranging from 0 to 14.

Omar Medina, manager of Tranques, Relaves y Recursos Hídricos, explained that “PAMo plays a fundamental role in the mining business chain. It not only supports copper extraction, but also generates significant social and environmental value. The treatment of wastewater and the proper disposal of mining tailings are key actions that are highly valued by our local communities.”

With an initial investment of US$42 million (original plant and its expansion), PAMo, which measures more than 1.5 hectares and processes 2,500 liters of water per second, has become one of the largest plants of its kind worldwide.

In addition, to ensure safe and efficient operation, the plant has its own tools and online monitoring systems from the Integrated Operations Center (CIO) of El Teniente, in Rancagua.

Sergio Guzmán, head of the Division’s Tailings Operations unit, added that “the process is subject to continuous online monitoring to ensure its ongoing compliance and water quality. We also have an automatic reporting system that facilitates the delivery of water quality parameters to the authorities.”

It also has a positive impact on community development by ensuring compliance with emission standards for water used by communities for agricultural activities. Over the past few years, awareness campaigns and guided tours have been organised so that community representatives can learn more about their facilities.