Submarine Tailings in Chile—A Review

Abstract

This review aims to understand the environmental impact that tailings produce on the land and marine ecosystem. Issues related to flora, fauna, and the environment are revised. In the first instance, the origin of the treatment and disposal of marine mining waste in Chile and other countries is studied. The importance of tailings’ valuable elements is analyzed through mineralogy, chemical composition, and oceanographic interactions. Several tailings’ treatments seek to recover valuable minerals and mitigate environmental impacts through leaching, bioleaching, and flotation methods. The analysis was complemented with the particular legislative framework for every country, highlighting those with formal regulations for the disposal of tailings in a marine environment. The available registry on flora and fauna affected by the discharge of toxic metals is explored. As a study case, the “Playa Verde” project is detailed, which recovers copper from marine tailings, and uses phytoremediation to neutralize toxic metals. Countries must regularize the disposal of marine tailings due to the significant impact on the marine ecosystem. The implementation of new technologies is necessary to recover valuable elements and reduce mining waste.

An Assessment of the Metal Removal Capability of Endemic Chilean Species

“…The problems generated by these environmental liabilities are deepening due to the limited resources of the municipalities that must take charge of these residues, which imposes the need to develop an economic, easy, and environmentally friendly technology to remediate the tailings. In 2019, the Chilean government detected 37 abandoned tailing impoundments with a potential risk for nearby towns, which constitutes less than 25% of the total abandoned impoundments and 5% of the total impoundments [ 3 , 49 ].…”

Past, Present, and Future of Copper Mine Tailings Governance in Chile (1905–2022): A Review in One of the Leading Mining Countries in the World

“…There is competition for land use between agriculture, livestock production, cities, and mining. While the limited land area for tailings disposal may drive consideration of the ocean as an alternative, it is important to recognize that local communities depend on the ocean as a major supplier of food and many livelihoods [ 9 ]. Environmental impact assessments of tailings disposal on land and at the bottom of the ocean are usually limited by budgets and time frames, resulting in a limited capacity to understand longer-term environmental risks to underground aquifers and marine ecosystems, including interactions between land and sea ecosystems (food chains) [ 10 , 11 , 12 , 13 ].…”

Development of an analytical model for copper heap leaching from secondary sulfides in chloride media in an industrial environment

“…Currently, 19.7 million tons of copper are produced worldwide [2], 75 % of which are processed by pyrometallurgical processes, while the rest is processed by hydrometallurgical routes [3][4][5]. Pyrometallurgical processes generate large environmental liabilities, such as tailings dams [6][7][8] produced by flotation processes, which can affect acid rains and increase local pollution [9,10]. Hydrometallurgical processes, together with copper bioleaching processes [11][12][13], have proven to be more environmentally friendly.…”