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

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.

1.3 Low land reclamation rate

Some developed countries have a long history of mining, and their governance concepts, measures and technologies started earlier. Since 1940, Germany has been reducing the destruction of the ecological environment in the mining process, while taking into account the ecological changes and residents' requirements for the environment from a macro perspective to carry out mine restoration and management. After 1960, some countries began to develop a variety of restoration methods for ecological restoration, and technology was at the forefront. Land reclamation is the main way of ecological restoration in mining areas. The land reclamation rate in European and American countries is more than 80%, while the land reclamation rate in Chinese mining areas is only about 20%, which is far lower than the international average level of 50%-70%. The State Council promulgated the "Regulations on Land Reclamation" in 1989, the "Regulations on Land Reclamation" in 2011, and the "Measures for the Implementation of the Regulations on Land Reclamation" in 2019. In the same year, the "Regulations on the Protection of the Geological Environment of Mines" were revised, and the State's policies, funding, governance methods and priorities for mine restoration have gradually improved and improved with the development of The Times.

1.4 Construction Difficulties

Before the mine restoration construction, a series of data such as start-up procedures, planning instructions, environmental impact reports and approvals, geological disaster assessment reports, geological exploration reports, etc., are the "blocking points" of mine treatment projects, such as tedious data preparation and approval procedures, difficult approval, and time-consuming handling. During the construction process, the local government needs to coordinate multiple relationships among departments, construction units, mining areas, and villagers. Most of the land occupied by the mining area is collective land. After construction, farmers need to deal with the issue of land transfer rent payment. Villagers are worried about the quality of land after reclamation and are unwilling to accept reclaimed land and other social problems.

2. Repair existing problems and improve measures

2.1 Repair Mechanism

The central and local governments attach great importance to the ecological restoration of mines, and have introduced more detailed systems to promote mine restoration. Local governments should strengthen the implementation of policies to maximize the enthusiasm of mining enterprises and various social resources. Local governments have rationalized the powers and obligations among departments related to mine restoration, formed a scientific and standardized system with natural resources departments as the main body and the active participation of ecological environment, forestry, water conservancy and other departments, refined the constraint and incentive mechanism, promoted coordination and communication among departments, and improved the enforcement power of ecological environment and forestry departments in the evaluation and supervision of ecological restoration quality. Improve the restoration speed and treatment rate of historical mining areas.