Present situation of mine environmental management

1.2. 1 Project implementation and capital investment

Before 1990s, due to system, management and historical reasons, China's mineral resources development was in a state of extensive management. Most mines sacrifice the environment, which leads to increasingly prominent mine environmental problems and frequent mine geological disasters, which not only threaten the safety of production and life of residents in mining areas, but also cause huge economic losses, seriously affecting and restricting the sustainable development of China's mining economy. At the beginning of 1990s, the trend of repeated destruction and deterioration of mine environment aroused widespread concern of the central government and governments at all levels, and the work of mine environmental management and ecological restoration was gradually put on the agenda. The former State Bureau of Land Management has successively established more than 20 different types of land reclamation pilot projects in coal, petroleum, nonferrous metals, gold and other mines, coal-fired power generation, brick burning and so on. The State Environmental Protection Administration, in combination with the pilot project of national ecological demonstration zone construction, has carried out the pilot project of environmental protection and ecological reconstruction in mining areas in Maanshan, Huaibei, Qian 'an and other cities and counties 10. Metallurgical, coal, chemical, non-ferrous metals and other departments have also started the pilot work of mine environmental restoration and management from the reality of their own industries. For example, since the Shenfu Dongsheng mining area was developed by 1986, Shenhua Group Company has adhered to the simultaneous implementation of development, construction and pollution control, and successively built a number of environmental protection facilities such as sewage treatment plant and slime water treatment system of coal preparation plant, creating a shelterbelt in the mining area, which not only effectively improved the water environment and atmospheric environment quality in the mining area, but also increased the vegetation coverage rate in the mining area from the original 14% to 39%. Another example is Nanshan Iron Mine in Maanshan, an old mine with a mining history of more than 80 years, and the surface vegetation has been completely destroyed. In order to do a good job in land reclamation, the mine established a reclamation leading group and a full-time reclamation team. After several years of efforts, the reclamation rate of abandoned land has reached 70%. Wangzhuang Coal Mine of Lu Shanxi Mining Bureau adopts the new technology of artificial afforestation and greening, which explores a new way for the greening of waste hills. Not only did it control the "three wastes" in mines, reclaimed the land and restored the ecology, but it also set an example and made contributions to promoting the environmental protection work in mining areas throughout the country.

From 200/kloc-0 to 2002, the Ministry of Finance and the Ministry of Land and Resources invested 23.5 million yuan from the royalties and prices of exploration and mining rights, and the local self-raised funds were 3052 1.6 million yuan. Select 16 provinces (autonomous regions and municipalities) with outstanding mine environmental problems in China, and arrange 18 state-owned old mines to carry out mine environmental control pilot projects (two pilot projects are arranged in Shandong and Hunan). The types of mining areas to be controlled include iron ore, coal mine, lead-zinc mine, copper mine and stone mine, and the control targets include mine environmental restoration and geological disaster control. The results of project acceptance show that due to the mutual support of the central and local matching funds, 90% of the projects have exceeded the design quantity, and the project quality of 18 has reached the expected requirements, and all of them have passed the acceptance. Through the implementation of the project, geological disasters, such as ground subsidence and debris flow, which have long threatened the safety of residents' production and life, have been treated, long-term abandoned and abandoned land has been reclaimed, and the ecological environment of the riddled mining area has been restored. Good economic and social benefits have laid a solid foundation for the smooth development of subsequent projects.

On the basis of the pilot experience, in June 2003, 5438+065438+ 10/0, the Ministry of Finance and the Ministry of Land and Resources issued the Notice on the Administrative Measures for the Use Fee and Price of Exploration and Mining Rights (for Trial Implementation), and officially began to use two special funds for mine environmental control. The main treatment targets are the state-owned mines built during the planned economy period, with the key points as follows: ① the treatment of mine geological environment damage such as ground cracking, settlement and collapse caused by mining activities; (2) Dealing with the decline of regional groundwater level, groundwater depletion and dangerous tailings dams caused by mining activities; ③ Treatment and comprehensive utilization of tailings formed by mining activities.

In recent years, the Ministry of Finance and the Ministry of Land and Resources have increased their investment in mine environmental management year by year. In 2003, 22 provinces (autonomous regions and municipalities) approved and implemented 74 mine environmental control projects, with a central investment of 654.38+72 billion yuan. In 2006, 3 1 provinces (autonomous regions and municipalities) approved and implemented 339 mine environmental control projects, and the central government invested 1, 31.60 billion yuan. Judging from the number of approved projects, there was a great increase in 2004 and 2006, with an increase of 129.73% and 75.77% respectively. The central government's investment in this project shows a steady growth trend, with an average annual growth rate of 66.30%. By the end of 2003 ~ 2007, 3 1 provinces (autonomous regions and municipalities) had approved the implementation of118 mine environmental restoration projects, and the central government invested a total of 376,543.8 billion yuan.

At the same time, with the strengthening of China's comprehensive national strength, according to the objectives of mine environmental governance in various provinces (autonomous regions and municipalities), according to the relevant requirements of the state and the need to ensure sustainable economic development, the investment of local finance in mine environmental governance is also increasing year by year. Moreover, because the state has issued a series of preferential policies to encourage participation in mine environmental governance, it has greatly mobilized the enthusiasm of enterprises and individuals to invest in mine environmental governance. According to incomplete statistics, since 2000, the local financial funds for mine environmental control in China have reached 400 million yuan, and the self-raised funds of enterprises have reached155438+0 million yuan.

1.2.2 Governance effectiveness

With the gradual improvement, perfection and further implementation of laws and regulations on mine environmental protection and supervision and management in China, as well as the increasing attention and supervision of national and provincial (autonomous regions and municipalities) administrative departments, and with the continuous improvement of public and mining enterprises' awareness of mine environmental protection, the trend of mine developers focusing on development but neglecting protection, wantonly destroying and polluting the mine environment has been effectively curbed. Especially after the Ministry of Finance and the Ministry of Land and Resources officially launched two special funds for mine environmental management, comprehensive management of mine geological environment was carried out in all parts of the country in an orderly manner, and the geological environment of some large and medium-sized state-owned mines, closed pit mines and mines without responsible persons was gradually restored and managed, which received good economic, social and environmental benefits. At the same time, the demonstration role of the implemented projects and the introduction of relevant encouragement policies have greatly inspired and stimulated the enthusiasm of enterprises and individuals to participate in mine environmental protection and governance, making the capital investment in mine environmental protection and governance more diversified, wider in scope and more remarkable in effect.

1.2.2. 1 Restoration and treatment of land destroyed by mine occupation

By the end of 2007, the total area of destroyed land occupied by mines in China had been restored155,000 hectares, with a control rate of 9.35%. At present, in the process of land restoration and treatment damaged by mine occupation, China generally follows the principle of unity of ecological benefits, economic benefits and social benefits, and requires that land reclamation planning should be coordinated with the overall planning of land use and the planning of basic farmland protection areas, and the reclaimed land should be mainly agricultural, suitable for grain, forest, grazing and fishing. Secondly, it is used for the construction of theme parks, artificial lakes and other ecological landscape restoration and other construction land.

(1) current situation of goaf subsidence control

Mining subsidence areas in China are mainly distributed in coal mines, followed by gypsum mines and gold mines. The treatment measures of subsidence areas are treated differently according to the scale of subsidence: for perennial waterlogged areas with deep burial depth, measures such as dredging and expanding capacity and reclaiming silt are generally taken to build artificial lakes, fish ponds and paddy fields; For seasonal waterlogging areas, it is necessary to dig ditches and drain water, build terraces and strips, and develop characteristic planting; The subsidence and deformation of the land, cut high sag, backfill leveling, replanting, planting trees and grass or as other construction land. For example, Huating County, Gansu Province reclaimed the subsidence area of Donghua Coal Mine and transformed it into a People's Square with an area of 86,400 square meters, which became a gathering and leisure place for county residents. Qitaihe city City, Heilongjiang Province comprehensively improved the subsided waters of coal mines, treated 9.26 hectares of subsided land, and built a scenic spot of Luoyan Lake with leisure and entertainment functions. Zaozhuang City, Shandong Province, in view of the collapse of gypsum mine, insisted on digging ponds to make land as a breakthrough, developed famous breeding industry, expanded mulberry planting area, and built a three-dimensional and efficient collapse control demonstration area combining planting, breeding and processing. More than 3,000 mu of subsided land has been treated, and fish ponds 133 have been excavated, covering an area of nearly 900 mu, and more than 2,700 mu of cultivated land has been transformed and leveled. The whole gypsum mining area began to enter the track of coordinated development of resource development and environmental protection.

(2) Current situation of open-pit mine management

With the development of construction activities in ecological provinces (autonomous regions and municipalities), administrative departments at all levels have treated damaged mountains and abandoned quarries within the visual range of "three areas and two lines" (namely, urban planning areas, scenic spots, geological relics protection areas, important roads or railways, and coastal coastline).

The principle of open pit mine management is to reduce the possibility of sudden geological disasters such as collapse and landslide, and to ensure the safety of life and property of residents in mining areas; Restore the destroyed surface vegetation in the stope to make it in harmony with the surrounding environment. At present, the main control measures are to unload unstable rock and soil first to eliminate the hidden danger of disaster, and then clean up and level the slopes and pits of soil mining to facilitate reclamation and greening; The bare mining face will turn green quickly by digging holes to backfill foreign soil or covering the net with foreign soil and spraying foreign soil on the rock slope. On the premise of cleaning up unstable rock mass, the Wangshan open pit in Suzhou, Jiangsu Province, which has a good treatment effect, adopts the method of guest soil spraying for bedrock slope with poor soil quality and large slope, and adopts construction techniques such as thick matrix method and greening technology for mountain with good soil quality and small slope ratio, which effectively protects the original exposed slope, reduces soil erosion and landslide hazards, and quickly changes the landscape. After three years of management, a natural population of mixed trees, shrubs and land has been formed, with vigorous vegetation growth, hardened roots and obvious biological protection. The reformed open pit mine has become a beautiful landscape in Suzhou Wuzhong Economic Development Zone. Weihai City, Shandong Province, according to the natural environmental conditions and local conditions, adopted a comprehensive control method combining earthwork engineering, plant engineering and spraying engineering to control the open pit mine. In 2000, * * * sprayed a steep slope of 300,000 square meters, with a total weir length of 9,000 meters, a fill volume of 1.8 million cubic meters, a stonework volume of 9,000 cubic meters, and planted 30,000 vines 1.5 million trees and shrubs. According to the vegetation restoration plan compiled by the mine every year, Shanghang Zijin Mining in Longyan City, Fujian Province follows the principle of "stability and restoration". At present, the combination of grass, shrub, arbor and vine has been implemented, and vegetation restoration has been carried out by artificial planting and mechanical spraying. 200 1 gold mining area, with 45,000 square meters of turf and 80,000 trees, the survival rate is over 85%. At the end of 20001,Zijin Mining started to implement the industrial tourism project of Zijinshan in order to implement the mine sustainable development strategy of "developing in protection and protecting in development". After 1 years of development and construction, it has invested 20 million yuan to build a unique emerging tourist area in Fujian Province. From 2002 to 2003, * * * received 68,000 tourists, and achieved a total tourism income of 865,438+500,000 yuan.

(3) The treatment status of tailings ponds and solid waste dumps.

In order to reduce dust, purify the air environment in the mining area, prevent and control geological disasters such as soil and water pollution, soil erosion and debris flow, increase the availability of land in the mining area, build green mines with beautiful environment, and control tailings ponds and solid waste dumps, which has become the main work of mine environmental management at present.

At present, the management principles of tailings ponds and solid waste dumps in China are diversified development, turning waste into treasure, improving utilization rate, reducing hoarding, reclaiming land and restoring ecology. Under the existing economic and technical conditions, tailings and solid wastes are widely used in construction, power generation and other industries, such as processing into new building materials or making bricks, paving roads and filling subsidence areas. Daye Iron Mine of Wuhan Iron and Steel Company, Hubei Province uses tailings to make new glass-ceramic granite building materials and antique ceramic handicrafts, and uses fine limestone powder tailings crushed by ore to produce high-grade cement. Anhui Tongling Nonferrous Metals Co., Ltd. belongs to the five-kilometer tailings pond, and a demonstration site of soilless reclamation has been built. Nowadays, the sandy tail "beach" has become a green belt along the river. The tailings pond of Zuoshan Mine Factory of Yunnan Tin Industry Group Co., Ltd. has been reclaimed into 225 mu of bamboo forest. For tailings and solid wastes that cannot be used, stopes and pits can be backfilled on the spot, covered with soil, used for artificial afforestation and restored to cultivated land. Or make full use of microbial technology to recover directly on the slag heap. Through various forms of control measures to control soil erosion, improve the ecological environment and restore the natural landscape. For example, in the reclamation of solid wastes from mines such as Xiaoyi in Shanxi and Pingguo in Guangxi, a series of accelerated green soil solidification technologies have been adopted, and a new process combining stripping, dumping and reclamation has been established. The microbial engineering technology of endophytic mycorrhizal fungi was used to increase soil activity, and the engineering reclamation and biological reclamation were organically combined, and the vegetation restoration of the dump was successfully realized.

1.2.2.2 Mine wastewater treatment

At present, the annual output of mine wastewater and waste liquid in China is about 6.088 billion cubic meters, the annual treatment capacity is 6.5438+0.68/kloc-0.000 billion cubic meters, the annual comprehensive utilization capacity is 6.5438+0.744 billion cubic meters, and the comprehensive utilization rate is 28.64%.

Mine wastewater can be divided into mining wastewater and mineral processing wastewater according to production technology; According to the pH value of wastewater, it can be divided into acidic wastewater and alkaline wastewater. Mine acid wastewater mainly comes from pit water, waste rock heap leaching filtrate and so on. Mine alkaline wastewater is mainly produced in mineral processing operations. The main pollutants in mine wastewater include heavy metals, acids, organic pollutants, petroleum pollutants, cyanide, fluoride and soluble salts. Heavy metal pollution and acid pollution are the most common waste water pollution. The heavy metal elements in wastewater mainly include lead, zinc, nickel, copper, mercury, chromium, cadmium, cobalt, manganese, titanium, vanadium and bismuth. At present, the treatment methods of mine wastewater in China mainly include neutralization method, microbial method and constructed wetland method. The treatment process is advanced and mature. For example, Jinchuan Company of Gansu Province has successively built treatment stations for precious metal ions and other wastewater discharged from different production processes such as mines, mineral processing, metallurgy, chemical power and so on, with an annual treatment capacity of 5 million tons, and the unused wastewater is discharged into tailings ponds, thus reducing the pollution and damage to the water and soil near the mining area.

1.2.2.3 mine geological disaster control

Since 1980s, there have been more than 2000 geological disasters 12000 caused by mining in China, with an affected area of 339,800 hectares and a control area of 67,900 hectares, with a control rate of 19.98%.

According to the development status, disaster-causing mechanism and harm degree of various mine geological disasters in China, combined with the level of national economic development and technical conditions, the principles and engineering measures of mine geological disasters control in China at this stage are as follows: ① For geological disasters with serious harm, great difficulty in control and unsatisfactory return on investment in control, relocation and avoidance measures are generally adopted. In June, 2003, when Premier Wen Jiabao of the State Council visited Liaoning, he issued "four military orders" on the management of mine geological environment: to implement it as soon as possible, to be open and transparent, to assign responsibility to people, and to increase investment. Soon, the relevant state departments began to arrange special funds for the treatment of subsidence areas in coal cities in Northeast China, and the governments of the three northeastern provinces went all out to invest in the treatment project of coal mining subsidence areas, with a total area of more than 900 square kilometers. Governance projects include the construction of residential quarters, maintenance and reinforcement of residential quarters, new supporting facilities such as schools, hospitals and kindergartens, and maintenance and reinforcement of some damaged schools, hospitals, roads, water supply (drainage) pipelines and heating pipelines. At present, Liaoning has resettled 28,000 affected residents in subsidence areas, accounting for more than 70% of the resettlement households. More than 2.4 million square meters of residential buildings and 250,000 square meters of supporting facilities such as schools and hospitals have been built. The newly-built residential area in the coal mining subsidence area of Jilin Province has a completed area of more than 820,000 square meters, accommodating10.36 million residents, and various supporting building facilities have also been carried out simultaneously. Heilongjiang province covers an area of more than 400 square kilometers. By the end of May, 2006, 2.23 million square meters of housing had been newly started, accounting for 78% of the issued plan. After the completion of the project, it is estimated that 33 1 12 households will be relocated in the subsidence area, accounting for 70% of the issued plan. (2) For sudden geological disasters such as point-distributed collapse, landslide and debris flow, measures should be taken, such as deploying group monitoring and prevention monitoring systems, implementing control projects, and carrying out special monitoring in key areas. For example, the deformation area of unstable slope (potential landslide) in Xiaochangba Lead-Zinc Mine 1 138 adit in Gansu Province is about 654.38+10,000 square meters, and the main inducing factor is the deformation and creep of residual slope gravel soil on high and steep bedrock slope due to the rise of groundwater level in flood season. On the basis of regular monitoring of slope displacement, engineering measures such as lattice reinforcement, retaining wall construction, surface drainage and planting trees and grass have been taken, which effectively inhibited the further development of slope creep deformation.

Problems in 1.2.3

In recent years, although China's mine environment restoration and management work has made some achievements, because the work has just started, policies and regulations, management mechanism, financial guarantee and technical standards need to be improved and improved. The main problems are as follows:

1.2.3. 1 mine environmental protection and governance has not yet entered the legal track, and the management mechanism is not perfect.

In recent years, although China has formulated and promulgated a series of laws and regulations related to mine environmental protection and governance, most of these laws and regulations are limited to the requirements of principle, and their operability is poor, so it is difficult to implement them concretely. In the management system, there are overlaps and gaps between law enforcement units. In particular, the relationship between the main unit of governance and the higher authorities and related units has not been clearly defined in many aspects, whether legally or economically. In the process of mine environmental management, what principles should be followed to establish the relationship between responsibilities, rights and interests of all parties? How to establish and protect the achievements after governance, that is, the ownership and use right of environmental property rights and reclaimed land? These problems are not covered by the original law and need to be improved urgently.

1.2.3.2 China's mining has a long history, with serious environmental damage and more difficult control.

For a long time, due to the weak awareness of environmental protection, imperfect laws and regulations on mine environmental protection, lagging management, and the influence of comprehensive factors such as mining conditions, mining methods, production technology, technical level and equipment conditions, the mine environment in China has been seriously damaged. China's mine environmental problems are widely distributed, with complex types, high disaster probability, strong suddenness, many hidden dangers and serious disasters. It not only seriously affects and restricts the development of the national economy, but also threatens the safety of people's lives and property, causing a series of social problems and contradictions. However, China's mine environment restoration and management started late, with small scale and limited investment. With the increase of mining scale and intensity, mine environmental problems will become increasingly prominent, and the control difficulty will become more and more difficult.

1.2.3.3 There is a shortage of funds for mine environmental protection and governance, and the investment mechanism is not perfect.

At present, the funds for mine environmental protection and governance in China mainly come from three parts: first, the central government arranges certain funds from the royalties and prices of the two rights, which is far from meeting the needs of mine environmental governance because of too many historical debts. Second, the local finance arranges some funds from the collected price and mineral resources compensation fees, which are mainly used for mineral resources exploration and other expenditures, and the expenditure for mine environmental management is extremely limited. The third is the deposit paid by mining enterprises for mine environment restoration and governance. Due to the large investment in mine environmental governance projects, its economic benefits are not prominent or lagging behind, and the lack of incentive policies and measures related to mine environmental governance leads to a small return on investment in mine environmental governance, so other funds are invested less and the investment mechanism is not smooth, and a diversified and multi-channel investment mechanism for mine environmental governance has not yet been formed.

1.2.3.4 technical standards and specifications for mine environmental protection and management need to be formulated urgently.

Although China has carried out scattered research work on mine restoration and management at different levels, and also carried out demonstration projects of different types of abandoned mines, there is still a big gap between the accumulated experience and data of these work and the standards and norms of the formation system, which leads to unclear objectives and tasks of mine environmental restoration and management in China, lack of basis for management effectiveness and irregular management technology. Therefore, the layout of mine environmental restoration and treatment projects is random, the technical content is low, and the treatment effect of some treatment projects is not obvious, so it is difficult to achieve the expected benefits. In order to improve the technical level of mine environmental protection and governance in China as soon as possible, and standardize the technical route selection, workload layout, quality control, budget preparation and expected achievement target setting of restoration and governance projects, it is suggested that the relevant state departments set up special funds and concentrate a group of technical forces to study and formulate methods, standards or norms for mine restoration and governance as soon as possible to guide the mine restoration and governance work in the whole society.

1.2.3.5 Emphasis on pre-treatment and light on post-treatment, which affects the effect of mine environmental treatment.

Since 200 1, a large number of mine environmental control projects have been carried out one after another. Most of the projects are in the early stage of governance. Because of the financial guarantee, the competent units and implementing units are very enthusiastic, not only strictly follow the design and construction, but also have great supervision. However, after the project was examined and accepted, due to the lack of follow-up financial support, the later maintenance work of some governance projects was in a state of stagnation, and the administrative supervision was also in a state of absence, which affected the governance effect to some extent.