Biowastes and inorganic additives are acknowledged efficient but site-dependent alternatives for in situ metal immobilization. The present study evaluates food waste-based compost, a particularly abundant type of biowaste in South Korea, and zeolite as amendments for increasing pH and reducing metal leaching potential in weathered tailings from an abandoned mine site. Two types of biowaste were used: food waste compost (60 % food waste and 40 % sawdust) and market compost (50 % food waste, 10 % agricultural waste, 10 % manure, and 30 % lime). Materials were thoroughly characterized. Leaching tests were then performed in reactors filled with various mixtures of organic–inorganic amended tailings, over a 4-week period. The in situ metal immobilization efficiency of compost was evaluated based on collected leachate quality. Results indicated that both organic and inorganic materials were successful for increasing pH (from 3.0 to up to 8.1) and metal immobilization, except for Pb and As, with which leaching potential increased in most amended reactors relative to un-amended tailings (up to 43 and 158 %, respectively). Over the duration of the experiment, the cumulative reduction of metal leaching potential ranked as follows: Zn (44–91 %) > Mn (4–76 %) > Cr (20–53 %) > Fe (34–44 %) > Cd (17–43 %) > Al (0.5–24 %). Among mixtures, combined biowaste and zeolite-amended tailings showed the best performance for increasing pH (7.5–8.1) and for metal immobilization. Chemical and biological processes, such as sorption and precipitation processes, were predominant. Overall, the study provides useful data on the efficient use of food waste compost for acid mine drainage prevention in South Korea.

Current patterns of agricultural expansion and intensification are bringing unprecedented environmental externalities, including impacts on water quality. While water pollution is slowly starting to receive the attention it deserves, the contribution of agriculture to this problem has not yet received sufficient consideration. We need a much better understanding of the causes and effects of agricultural water pollution as well as effective means to prevent and remedy the problem. In the existing literature, information on water pollution from agriculture is highly dispersed. This repost is a comprehensive review and covers different agricultural sectors (including crops, livestock and aquaculture), and examines the drivers of water pollution in these sectors as well as the resulting pressures and changes in water bodies, the associated impacts on human health and the environment, and the responses needed to prevent pollution and mitigate its risks.