1. Analysis of factors affecting the development trend of mine geological environment
(A) favorable factors to promote the improvement of mine geological environment
1. The overall planning of mineral resources in Hunan Province and other related plans were gradually implemented.
In the past ten years, Hunan Province, cities and counties have formulated the "Eleventh Five-Year" and "Twelfth Five-Year" plans for mineral resources. Mineral resources planning at all levels has clearly planned resource development and mine geological environment protection. The general principle is "developing in protection and protecting in development", which promotes the coordinated development of resource development and environmental protection, and changes the growth mode of mining economy from extensive management mode that relies on consuming a lot of resources and sacrificing the environment to intensive management mode that relies on scientific and technological progress and improves economies of scale. Some mineral development projects with small scale, poor economic benefits, great environmental damage and many potential safety hazards will no longer be approved. In the future, existing mines will be closed, indigenous mining and smelting will be banned, new and rebuilt coal mines with sulfur content greater than 1.5% will be restricted, and new coal mines with sulfur content greater than 3% will be prohibited. The 2008-20 15 Hunan Mine Environmental Protection and Restoration Plan defined the objectives, tasks and specific indicators of mine geological environmental protection. The implementation of these plans will help to ensure that the mine geological environment in this province will gradually develop in a good direction.
2 mine geological protection and restoration management system, laws and regulations and monitoring institutions gradually improved.
On June 24, 2002, the 27th meeting of the Standing Committee of the Ninth National People's Congress of Hunan Province passed the Regulations on the Protection of Geological Environment in Hunan Province, in which Articles 9, 10, 11, 12 and 13 put forward relevant regulations on the protection of geological environment in mines. Decree No.44 of the Ministry of Land and Resources issued the Regulations on Mine Geological Environment Protection, which came into effect on May 1 2009.
According to the requirements of the Regulations on Geological Environment Protection in Hunan Province, Hunan Province has vigorously promoted two systems: one is the mine geological environment impact assessment system, and the technical specification for mine geological environment impact assessment in Hunan Province has been issued. Only when the evaluation conclusion in the mine geological environment impact assessment report is basically suitable-suitable, can the mining license be processed, and at the same time, a protection plan is set up in the report to guide the mine to carry out the mine geological environment protection and management; Second, according to the deposit system for mine geological environment restoration and treatment, the corresponding acceptance methods and standards have been formulated, requiring mines to pay the deposit for mine geological environment restoration and treatment in full, and the production mines can only be carried forward after they are basically qualified or qualified by relevant qualification units in stages, while the deposit can only be returned to the mining right holder after the closed pit mines are qualified.
According to the requirements of the Regulations on the Protection of Mine Geological Environment, Hunan Province requires all mining rights holders to prepare a plan for the protection and restoration of mine geological environment (including land reclamation) and restore it according to the planning requirements. The scheme of mine geological environment protection, treatment and restoration (including land reclamation) provides technical support for mine restoration and treatment.
In addition, Hunan Province requires strict implementation of the "three simultaneities" system for mine construction, so as to ensure that all environmental protection and treatment facilities are designed, constructed and put into operation simultaneously with the main project.
The concrete implementation of these management systems has restrained the occurrence of mine geological environment problems to a certain extent, and managed to restore the damaged mine geological environment at the same time.
In recent ten years, cities (states) and most counties (cities) in Hunan Province have set up special geological environment management institutions to strengthen the protection of mine geological environment, exercise supervision and management duties over mine geological environment, urge the concrete implementation of the "three simultaneities" system, regularly check the implementation, and order mining enterprises with serious geological environment damage to treat within a time limit. According to the principles and policies of the state, we should comprehensively use economic, legal and necessary administrative means to close mines with poor product quality, waste of resources, serious pollution and no conditions for safe production.
3. Mining management has been gradually strengthened, and the mining order has gradually entered the right track.
In recent years, Hunan Province has intensified its efforts to rectify the order of mineral resources management. Since 2000, more than 2,000 illegal mines have been banned in the province, and the phenomenon of indiscriminate mining and excavation in some places has been effectively stopped; According to the spirit of "Notice of the State Council on Comprehensively Rectifying and Standardizing the Order of Mineral Resources Development" (Guo Fa [2005] No.28), Hunan Province has formulated the overall plan of mineral resources integration in Hunan Province. After the implementation of the plan, the number of mines in the province has decreased significantly. Compared with 2003, the number of mines decreased by more than 1500, which gradually changed the situation of small mines and many mines, upstairs and downstairs.
According to the spirit of Opinions of the General Office of the State Council on Further Strengthening the Work of Coal Mine Safety Production (Guo Ban Fa [2065438+03] No.99), on the one hand, it is required to speed up the closure and withdrawal of backward small coal mines, focusing on the closure of 90,000 tons/year and below coal mines that do not have safe production conditions, serious disasters such as coal and gas outburst, and major and above accidents, and refuse to return to ultra-deep cross-border areas and run out of resources, and refuse to implement the order to stop production and rectify. On the other hand, the safety access conditions for coal mines are strict, and the approval of new coal mines with a capacity of less than 300,000 tons/year and coal and gas outburst mines with a capacity of less than 900,000 tons/year is stopped. ..
4. Efforts to restore and control the mine ecological environment have been gradually increased.
With the deterioration of ecological environment and the instability of local order caused by mine geological environment problems, the state, local governments and mining enterprises have gradually increased their investment in the restoration and management of mine geological environment. For the problems of mine geological environment and the loss of responsible persons left over from history, the central and local governments have gradually raised funds to carry out a number of governance work in accordance with the principle of priority; For mines with responsible subjects, with the institutional constraints of mine geological environment in Hunan Province and the improvement of local people's awareness of rights protection, mines are gradually carrying out the restoration and management of mine geological environment. In the past ten years, the funds raised by the central and local governments for mine restoration and management have increased from tens of millions to hundreds of millions of yuan each year, and the funds raised by mining enterprises have also increased from tens of millions to hundreds of millions of yuan each year.
By the end of 20 13, there were nearly 200 mine restoration projects funded by the central and local governments in the province, and all production mines in the province started mine environmental restoration projects to varying degrees. A series of demonstration projects of mine geological environment restoration and management, such as Shizhuyuan in Chenzhou, are being carried out gradually. At present, Hunan 17 mine has successfully declared the second and third batch of national green mines, and is actively preparing for construction. In response to the spirit of "vigorously promoting the construction of ecological civilization" at the 18th National Congress of the Communist Party of China, Hunan Province has compiled a provincial-level "mine greening" action plan, organized cities and states to prepare corresponding greening action plans, and organized and implemented a number of typical mine greening demonstration projects. The above-mentioned mine geological environment restoration and treatment projects and related schemes are beneficial to the restoration of mine geological environment in Hunan Province.
5. Improvement of mine geological environment control technology
At present, the technology of waste treatment, waste recovery and comprehensive utilization in Hunan Province is constantly improving, such as coal gangue power generation, brick making, waste stone road construction, foundation accessories, solid waste used for goaf filling and so on. In recent years, the comprehensive utilization effect of coal gangue is the most obvious, and a large amount of coal gangue is consumed. At present, Hunan Province is exploring some control technologies for complex mine geological environment problems, such as heavy metal contaminated land remediation technology, tailings cemented filling goaf technology, ground deformation monitoring technology and so on. The perfection of these new technologies for mine geological environment control will help to gradually restore and control some complex mine geological environment problems.
6. The mining depth of some underground mines has gradually increased, and the impact on the surface has gradually weakened.
Over the years, mining activities have prevailed, and the shallow resources of some underground mining mines have been completely exploited, which will gradually extend to the deep in the future, thus gradually reducing the disturbance impact on the surface, and the ground deformation zone formed in the goaf is becoming more and more stable. For example, in some large-scale water mining areas such as Ningxiang Coal Dam, with the deepening of mining, karst gradually weakens, and the probability of water inrush events decreases, thus reducing the possibility of karst ground collapse.
(B) unfavorable factors that promote the deterioration of mine geological environment
1. The development of national economy is highly dependent on the development of mining industry, and the development of local mineral resources is further intensified.
Hunan province is in the stage of sustained and rapid development of industrialization and urbanization, which will be characterized by a large consumption of natural resources. At present, the guarantee of mineral resources to the national economic and social development of the province has become a bottleneck, the demand for mineral products continues to be strong, and social funds have poured into mining development. It can be predicted that the development intensity of mineral resources in the province will be further increased in the future, and the mine geological environment will inevitably be adversely affected. In particular, some areas rich in mineral resources are listed as key mining areas, and the geological environment problems of mines are bound to increase.
2. Poor mineral resources endowment conditions and fragile geological environment of the mine.
Hunan province is rich in mineral resources. Except for a few large-scale nonferrous metal deposits, it has the characteristics of small scale, thin thickness, low grade, deep burial, many associated minerals and complex occurrence state of useful components, which makes it difficult to concentrate mining on a large scale, complicated beneficiation and smelting process and low recovery rate. Most coal mines and gypsum mines have poor engineering geological conditions, and most coal mining areas and major large and medium-sized non-ferrous metal deposits have complex hydrogeological conditions and poor mining technical conditions. Most metal minerals are distributed in mountainous areas with poor topographic conditions, such as southern Hunan, and another area where coal resources are mainly mined. There are many important construction projects, such as surface residential projects and cultivated land. Mine ecological environment is fragile, and mining activities are easy to cause mine geological environment problems.
3. It will take some time to improve the mine geological environment management system.
At present, the phenomenon of illegal mining and indiscriminate mining of mineral resources has been effectively curbed, but it still needs a process to put an end to this phenomenon; There is still a process to implement the reserve fund for mine geological environment management, improve the acceptance method and management system for mine geological environment restoration and management, and it also needs a process to show the management effect.
4. The awareness of mine environmental protection of mining right holders needs to be strengthened.
The understanding and enthusiasm of mining enterprises in Hunan Province for mine environmental protection and governance are unbalanced. Most large and medium-sized mining enterprises have a high degree of understanding, but a considerable number of township collective or private small mining enterprises generally attach importance to resource development and ignore environmental protection and governance.
5. The geological environment management organization and monitoring system of mining enterprises are not perfect.
A few years ago, due to the decline in economic benefits of mining enterprises, environmental protection workers in state-owned and state-controlled mining enterprises and large private mines became the main targets of layoffs, and some environmental protection posts and functional departments were either merged or revoked. However, most township collective mines and individual mines have basically not set up special environmental protection institutions, and there is no special person to dynamically monitor and manage the geological environment problems of mines.
At present, although some cities and counties (cities) in the province have established mine geological environment management institutions, such as geological environment departments (institutes) and geological environment monitoring stations, there are still some gaps in staffing, technical strength, equipment and lack of funds, and the construction of dynamic monitoring system of mine geological environment in the province needs to be strengthened.
6. The compensation mechanism of mine geological environment restoration is not perfect.
Due to the constraints of mining methods, resource endowments and mining conditions of mineral deposits in Hunan Province, the most prominent and serious mine geological environment problems in Hunan Province are still ground deformation in mined-out areas and karst ground collapse. Especially in some fields, it is common to replace governance with compensation. Mining enterprises pay the management funds to the person in charge of damaged houses, but the damaged households are not used for house reinforcement. Even dangerous houses, or because the compensation funds did not meet the requirements of the damaged households, or because it was difficult to relocate and locate, some damaged households did not attract enough attention. Some mining areas have ground subsidence, and even if mining enterprises are willing to raise funds for remediation and restoration, they cannot do so because of the obstruction of local villagers. Therefore, how to completely solve the situation of replacing governance with compensation remains to be actively explored and studied at the institutional and legislative levels.
Second, the development trend of mine geological environment
(A) the overall development trend of mine geological environment
With the increase of investment in governance, the improvement of governance technology, the enhancement of management binding force, the improvement of relevant systems and the improvement of environmental awareness of mining rights holders and affected objects, the speed of mine geological environment restoration and governance in the province is obviously faster than that of destruction, and the new area of governance is greater than the expanded area of destruction, and the overall mine geological environment is gradually improving.
However, in areas where local mineral resources are concentrated, such as Lianshao coalfield in central Hunan, Shaoshan coalfield in central Hunan, Chen Lei coalfield and non-ferrous mining area in southern Hunan, and antimony mining area in central Hunan, a large number of mine geological environment problems have appeared in recent years, such as the increase of three wastes discharge, the intensification of water and soil pollution, especially heavy metal pollution, the intensification of ground deformation and karst ground collapse in goaf, and the deterioration of mine geological environment to a certain extent.
(2) Forecast the development trend of mine geological environment problems.
1. Development trend prediction of mine geological disasters
(1) The ground deformation, ground fissures and karst ground collapse in mined-out areas will gradually decrease.
By the end of 20 13, 826 mines in the province had caused 1620 geological disasters, mainly distributed in Lianshao coalfield in central Hunan, Chen Lei coalfield in southern Hunan, Huangfengqiao-Taoshui coalfield in eastern Hunan, Hekou-Zhatian coalfield in northern Hunan, gypsum coalfield, Ningxiang coal dam coalfield and Chenxi coalfield in western Hunan. According to the analysis of mineral resources and mine production capacity in the main ground deformation areas, the mining areas with service life of more than 10 mainly include the coal mining areas in Loudi City, Jiaodi-Shaodong Niumasi in Shaoyang City, the coal mining areas and gypsum mining areas in Changle, the coal mining areas in Tanjiashan, leiyang city, Yongxing County, Changning City, Beihu District in southern Hunan, Yuanjia Coal Mining Area in Jiahe County and Baoshan-Huangsha Coal Mining Area in Guiyang County. These mining areas will be exploited for a long time in the future, which will aggravate and cause ground deformation disasters. However, because most of the reserved resources are located in the deep, the damage to the surface is less than that of shallow resources, so the ground deformation is on the rise but generally slows down. At present, there are few mineral resources in Xiangtan Manganese Mine, Huang Feng Bridge-Lancun Coal Mine, Zixing Sandu Coal Mine, Ningxiang Coal Mine, lengshuitan Coal Mine, Qiyang Coal Mine, Changde Coal Mine, Shuikoushan Lead-zinc Mine and other mines (regions) with serious ground deformation. According to the existing production scale, most of them have a service period of less than 15 years, usually within two to seven years, and most of them have retained resources. Loudi Enkou and Qiaotouhe coal mines with serious ground subsidence have all been closed, and the disaster of mine ground subsidence has been obviously alleviated, which will continue to improve in the future.
(2) The incidence of geological disasters such as landslides and collapses in mines will decrease.
Landslide and collapse disasters in mines are mainly related to open-pit mining, and the general trend is that the existing open-pit mining is deepening and increasing. According to the current management mode of open-pit mining, this kind of disaster will be aggravated. However, the number of open-pit stopes such as sand yards and brick factories will be closed for policy reasons, and some open-pit stopes will be turned into underground mining due to resource exhaustion or difficulty in mining, and the number of stopes will show a downward trend, leading to the overall decline of mine landslides and collapses.
(3) The local debris flow in the mine is still likely to intensify.
Mine debris flow is mainly caused by nonferrous metal mines in southern Hunan. After years of mining, a lot of waste residue and tailings have been accumulated. At the same time, most mines are rich in resources, and a large amount of mine solid waste will still be discharged to the surface for a long time. Southern Hunan is often affected by tropical storms, and heavy rainfall often occurs. Therefore, if effective preventive measures are not taken, the mine debris flow will be intensified.
2. The destruction of mine groundwater resources will continue to intensify.
The destruction of groundwater resources is an unavoidable mine environmental problem in mining development, especially underground mining. With the depletion of shallow resources, the mining depth is getting deeper and deeper, the water level is falling deeper and deeper, and the range of groundwater drainage is getting wider and wider. Except for closed pit mines such as Enkou Coal Mine and Qiaotouhe Coal Mine in Loudi, the destruction of groundwater resources in most underground mining mines will be intensified.
3. Analysis of the development trend of mine occupation and destruction of land
Mining activities in Hunan Province occupy and destroy land through four ways: mine ground construction, mining field, solid waste discharge (including tailings pond) and ground deformation. According to the occupation and destruction modes, they are described as follows:
(1) The area occupied by mine ground construction projects is reduced.
By the end of 20 13, the land occupied and destroyed by the construction of mine ground facilities in the whole province was the most, with an area of about 6680hm2, accounting for 32.65% of the total occupied and destroyed land area. In recent years, mine integration has been very strong. By the end of 20 13, 6 120 mines were under construction and put into operation in the whole province. Compared with 2008, the number of mining enterprises decreased by 1857. According to the national industrial policy, mine integration will be normalized, the number of mines will be further reduced, and the ground construction projects required for mine production will also be reduced accordingly.
(2) The land occupied and destroyed by the mine field will show a downward trend.
The land resources occupied and destroyed by mining areas are mainly caused by building materials mining, among which clay brick factories and quarries are the main mines that occupy and destroy land. Since September 2003, our province has gradually banned the use of solid clay bricks in urban construction projects in the province. At present, the number of clay brick factories has been significantly reduced, and will be further reduced in the future, and the occupation and destruction of land resources by clay brick factories will show a decreasing trend. In recent years, the infrastructure construction in Hunan Province is strong, the urbanization process is rapid, and the demand for building stones is great. A number of large cement production lines have been built, which will increase the occupation and destruction of land by quarries. However, most of these quarries are located in hilly areas with exposed bedrock, and the occupation and destruction of land are mostly exposed rocks, with limited increase in area. Therefore, the occupation and destruction of land in mining areas will generally show a downward trend.
(3) The growth trend of solid waste occupying and destroying land will slow down.
By the end of 20 13, the annual discharge of solid waste in the province was about 47.3 million tons, the accumulated storage was about 610.7 million tons, and the annual comprehensive utilization was about15.3 million tons. At present, the annual comprehensive utilization of mine solid waste is less than the annual output, and its occupation and destruction of land resources are increasing, but the comprehensive utilization of mine solid waste will increase.
(4) The deformation of mined-out ground and the collapse of karst ground will reduce the damage to the land as a whole, and may be aggravated locally.
According to incomplete statistics, by the end of 20 13, mined-out ground deformation and karst ground collapse destroyed land resources by about 4 100hm2, accounting for 19. 17% of the destroyed land occupied by mining activities in the whole province. In the above-mentioned mines (regions) where the ground deformation and karst ground collapse are aggravated, the destruction of land resources will also show an upward trend, while in other mines (regions).
In a word, Hunan Province is located in the monsoon climate zone, which is conducive to the growth of vegetation. Some gangue hills with high carbon and argillaceous components are easy to turn green naturally after weathering. Coupled with the gradual improvement of relevant laws, regulations and technical standards, mine environmental management has been strengthened, the awareness of mine owners to protect mine environment has been gradually improved, and the initiative of mine occupation to destroy land reclamation has been enhanced. Therefore, the overall situation of mine occupation and destruction of land resources in Hunan Province will show a downward trend, but in some concentrated mining areas with large mine reserves, due to strong mining activities, the situation of ground deformation and solid waste discharge in mine goaf will still show an upward trend.
4. The overall pollution of mine water and soil environment will tend to improve.
With the strengthening of management, the improvement of management system, the implementation of mine environmental control projects such as water pollution control and land restoration, the overall environmental pollution in mines will tend to improve. However, in the middle and high sulfur coal mining areas such as Huanglancun coal mining area in Youxian County, Qingtangpu coal mining area in Anhua County, Shaping coal mining area in Lianyuan County, Shizilu coal mining area in Xinshao County, Wenping coal mining area in Wugang County and Shejiao coal mining area in Xinning County, the mine drainage is large, and most of them are untreated acidic-strong acidic, which will aggravate the pollution of surface water and land resources flowing through this area in a short time. Shizhuyuan Metal Mining Area, Xianghualing Nonferrous Metal Mining Area, Baoshan-Huangshaping Nonferrous Metal Mining Area, Qitianling Nonferrous Metal Mining Area, Shangbao Pyrite Mining Area, Xiangxi (North) Yuanling-Chenxi Metal Mining Area, Hongjiang Vanadium Mining Area, Sangzhi Baishi Coal and Pyrite Mining Area, Hu Da Nickel-Molybdenum Mining Area, Shimen Xionghuang Mining Area, Dingcheng Stone Coal Mining Area, Anhua County 7 15 Mine and Although some mines in these mining areas have taken measures to prevent and control mine environmental pollution, they are far from meeting the needs of mine environmental pollution prevention and control, and mine environmental pollution will still show an upward trend in the short term. Mine environmental pollution in other areas will be generally improved.