ABSTRACT
The two pilot areas selected for researching suitable strategies and methodologies for rehabilitating mine tailings were the Mao Jia Wan tailings pond in Zhong Tiao Shan, a mountain range about 1,000 km south of Beijing, and the Wu Gong Li tailings pond in the floodplain of the Yangtsg River on the outskirts of Tong Ling, a major copper-producing center and city 180 km southwest of Nanjing. In earlier rehabilitation works in the Zhong Tiao Shan area, some older tailings ponds had been covered with 1 to 1.5 m of locally quarried reddish brown loess material, with a dominantly silty clay loam texture (34% clay), prior to release of the remade land to farmers. A few samples of this material proved to have a cation exchange capacity of about 40 meq 100 g−1 and between 0.2 and 4.0% finely disseminated calcium carbonate and occasional gypsum crystals. It is understood that cropping on these rehabilitated tailings ponds was successful from the start. However, covering tailings with such a thick layer of imported soil material entails major costs. Moreover, the loess is not necessarily as plentiful in other locations where it could be used for rehabilitation.
