Study on ecological restoration status and treatment countermeasures of abandoned mines left over from history

China has about 800,000 mines, of which about 400,000 are in need of restoration due to ecological damage. The "China Mineral Resources Report (2020)" and the "2020 Coal Industry Development Report" pointed out that about 40% of the old problems have not been treated, but the annual control rate of newly damaged land is only about 40%. In the early stage of economic development, the mining development mode is simple and extensive, and the environmental pollution control is not paid enough attention. After the establishment of the Ministry of Land and Resources in 1998, the state level supported the restoration and management of mining geological environment. In 2006, the Ministry of Finance, the Ministry of Land and Resources and the State Environmental Protection Administration jointly issued the Guiding Opinions on Gradually Establishing the Responsibility Mechanism for Mine Environmental Management and Ecological Restoration, which put forward the basic ideas of the deposit system for mine geological environment restoration and management. The difficulty of mine environmental management is the low level of restoration technology and the relative lack of professional personnel.

In order to solve the outstanding problems existing in the process of ecological restoration of mines, national and local policies have been introduced, for example, Notice on carrying out the National Verification Work of Historical Mines, Opinions on Exploring the use of market-oriented methods to promote the ecological restoration of Mines, Notice on Supporting the ecological restoration Demonstration Project of Historical abandoned Mines, Measures for the Implementation and Management of Ecological Restoration of Mines in Shandong Province, Action Plan for Comprehensive Management of Mines in Hebei Province, and on Strengthening the control and protection of mineral development Decision of state environment, etc. According to the overall framework of ecological civilization construction, follow the principle of government-led and market operation, encourage social capital to participate in the ecological restoration and management of mines through concept changes and policy guidance, adopt a systematic, scientific and standardized governance model, improve the ecological restoration capacity of mines, and achieve the ecological restoration goal.

The abandoned mines left over from history destroy the natural landscape, and there are hidden dangers of geological disasters such as landslides and collapses. The environmental pollution caused by mining reduces the local biological population, so it is imperative to restore the ecological management of mines. There are many deficiencies in the main aspects of the restoration system, such as the restoration mechanism, the restoration fund, the restoration mode, the restoration project, and the restoration technology, which lead to the low quality and slow speed of the restoration. Therefore, summarizing the problems of the mine ecological restoration and putting forward targeted measures and suggestions are conducive to forming a complete mine restoration system and accelerating the progress of the mine restoration.

l. Management status of historical mines

1.1 Large inventory and heavy task

Remote sensing survey and monitoring data show that by the end of 2018, the country's mining occupied about 3.60×l04km2 of damaged land; The land occupied and damaged by historical and mining mines is about 2.27×l04km2 and 1.33×l04km2 respectively. The storage of solid waste such as state-owned tailings ponds and waste slag fields occupies a large amount of land, and many environmental problems are left after private mining. Most of the mines left over from history are small and medium-sized mines with disorderly exploitation and scattered distribution, which have serious ecological damage and wide influence. Mine restoration is a complex systematic engineering, involving geology, hydrology, environment and many other aspects, the engineering amount is huge, the restoration period is long.

1.2 Strong governance needs

Mining is mostly open-pit mining, the mountain and vegetation damage is more serious, the natural habitat of wild animals and plants is damaged, the mountain collapse and landslide, flash floods and debris flows and other disasters occur from time to time, seriously affecting the life of the people around the mining area. To restore the geological environment and ecological environment of the mine, control the pollution caused by mining, and make it coordinate with the surrounding natural environment, the public has an urgent need for the treatment of abandoned mines. In 2021, the second round of central ecological environmental protection inspectors received a large number of complaints from the masses about pollution caused by mining, some mines illegally occupied woodlands, large areas of mountains were exposed, dust polluted the atmosphere, heavy metal polluted orchards and other serious phenomena, which have been reported on the official website of the Ministry of Ecology and Environment as typical cases of inspectors.