The land was largely abandoned, or just held for speculation to transform it to residential and industrial use.

土地大量的被遗弃或者被转成居住或工业的用途。

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Also abandoned shaft and mined-out area repaired can be used for depositing waste slag from mine itself and other industrial waste to mitigate a contradiction between waste site and cultivation land.

修复利用废弃巷道和采空区，储存矿山自身产生的废渣和工业废渣，缓解废石场与耕地争地的矛盾。

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