161-10 Filtered Tailings in Indonesia: The Catastrophic Failure of a Disruptive Technology

Session: Dynamics of Natural and Built Environments

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Abstract:

From 2015 to 2024 production of nickel in Indonesia increased from 5.7% to 59.5% of world production with the opening of seven high-pressure acid leaching (HPAL) projects from 2021 to 2025. An additional 14  and 12 HPAL projects have been permitted and proposed, respectively. Although HPAL and filtered tailings combine the demand for nickel with the less environmentally destructive alternative of filtered tailings to create the complete “green” package, the explosion of HPAL and filtered tailings in Indonesia has been a catastrophic failure. Target water contents for HPAL tailings are 30-35%, so that the use of the name “Dry Stack Tailings Facility” (DSTF) for the PT Halmahera Persada Lygend (HPL) project on Obi Island is a marketing term. Two 2020 reports showed that, in response to seismic activity, the DSTF,  the foundation, and the rockfill buttresses will all be unstable. A 2022 report noted the lack of any monitoring data and described the failure of the DSTF as an “uncontrolled risk.” The DSTF was constructed without quality control with water contents ranging from 8-36% and compacted densities ranging from 0.93-2.20 t/m³. Revision 1 of the 2022 report included a photo with the heading “View of DSTF area with significant water ponding” plus the statement “During the site visit, some issues with water ponding and poor drainage appeared to be present … given the height of the facility (57 m), the lack of quality control in the placement of tailings, and the observed surface water issues, further study is required.” By the final version, the caption had become “View of dry stack tailings facility area,” and “During the site visit, some issues with water ponding and drainage appeared to be present,” as well as “and the observed surface water issues” were removed. On March 16, 2025, the PT Huayue Nickel Cobalt (HYNC) filtered tailings facility on Sulawesi Island failed by liquefaction. On March 21, 2025, a landslide occurred at the adjoining PT Qing Mei Bang (QMB) New Energy Materials facility, resulting in three deaths. More failures have occurred since earlier satellite imagery shows a landslide from the PT HYNC facility with channels leading to the Bahodopi River. The response from PT QMB was that the rainfall that triggered the fatal landslide was “beyond human control.”

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-7180

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