| Bucket-line gold dredges vanished from North America but are thriving in China, Mongolia, Siberia and the Russian Far East... | ABSTRACT The study set out to determine the current status of bucket-line gold dredges in the placer gold industry. The article shows that this type of mining dredge is still of great economic importance. Bucket-line dredges continue to be built for placer gold mining, particularly small-sized dredges but also large dredges. Bucket-line dredges continue to be the most important placer gold machines in Siberia, Russian Far East, China and Mongolia.
The ‘digging end’ of the bucket-line dredge is the peak of Best Available Techniques (BAT) from the standpoint of operational efficiency, production cost and minimal environmental impact. The ‘disposal end’ of the bucket-line dredge is almost BAT when fitted with rear stacker conveyor, but a major advance can be made by pumping waste fines from the wash-plant over the stacked coarse tailings to encourage soil formation and trigger natural colonisation by plants.
Bucket-line gold dredges have had “100 years of bad press” from contamination by mercury lost from on-board wash-plants, and from failure to rehabilitate the mined areas after dredging. However rehabilitation to very high standards are now published, and there is a fresh awareness among ecologists of the very high ecological value of abandoned dredge tailings in displaying seral change with a high degree of naturalness. DOWNLOAD ARTICLE
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