Five major regional mine environmental geological problems

2. Macro construction of mine environmental restoration and governance model

The mode of mine environmental restoration and management is a tool to prevent and solve the contradiction between mine environment and problem restoration. Based on the conditions of mine development and utilization and the geological environment background of mine, it is necessary to grasp the law of problem occurrence and put forward preventive measures on the one hand, and repair and control the existing mine environmental problems on the other hand. Therefore, the model is based on the practice of mine environmental restoration to carry out theoretical research, with both typical mine environmental restoration project cases as the technical research background and specialized research on restoration technology, combining the mine environmental restoration experience in different regions of China with the mine restoration theory. A set of mine environmental restoration model with reasonable technical composition, suitable for mines in different areas and complete system has been formed.

The primary task of mine environmental restoration and management model research is to deeply understand the mine environmental problems. Domestic scholars have many classification schemes for mine environmental problems, such as classification based on mine development stage, classification based on mineral species, classification based on the manifestation and impact results of mine environmental geological problems, and classification based on the characteristics of mine environmental geological problems. In the study of model objects, the author focuses on the comprehensive classification scheme of problem nature, and divides common mine environmental problems into: Ground collapse problem, solid waste problem, liquid waste problem, open-pit slope stability problem, water layer structure damage problem and mine secondary geological disaster problem.

According to the functional requirements of the model, the author divides it into three functional sub-modules: engineering disaster elimination module, ecological restoration module and biological restoration module. The functional module of mine environmental restoration and governance mode is shown in Figure 2, in which the main function of the engineering disaster elimination module is to eliminate or prevent regional disaster hazards. The technical types of the module include disaster elimination and restoration technology and engineering restoration technology, which are mainly used to strengthen and transform surface rock and soil bodies and prevent unsafe hazards such as rock and soil bodies and geological bodies. The main function of the two sub-modules, ecological restoration module and biological restoration module, is to promote the restoration of rock and soil mass and ecological environment, and use ecological restoration technology and biological restoration technology to cooperate with the engineering disaster elimination module to complete the mine environmental restoration, so as to achieve the land restoration and ecological restoration goals of the model.

According to the decomposition of mode function modules, the author sets the code for the engineering disaster elimination module, ecological restoration module and biological restoration module in the order of constituting technologies as follows: Disaster elimination and restoration technology (Ai ~ Di), ecological restoration technology (Ei), biological restoration technology (Bei), the code is conducive to the systematic description of the composition of the model, and the macro construction of the mine environmental restoration management model such as "Ai+Bi+Ci+Di+Ei+Bei" and other organic construction of mine environmental restoration technology.

3. Establishment process of mine environmental restoration and management model

The establishment process of mine environmental restoration and governance model is shown in Figure 3. "Restoration of mine environmental problems" is the first step, which goes through the study of technology and objectives, and constitutes the establishment process of the model in a clockwise cycle. In this process, the restoration and governance technology and problems, and the restoration and governance objectives and problems have mutually feeding effects of benefit feedback, and each step has different influence characteristics on the model.

The restoration of mine environmental problems, namely: the understanding of the restoration object, mainly includes the investigation of mine geological environment, the assessment of geological environmental problems, and the typical treatment project cases. Mine environmental investigation refers to five aspects: mine geological environment investigation, mine water environment investigation, mine ecological environment investigation, mine atmospheric environment investigation and mine space environment investigation. This paper focuses on the geological environment survey of mines, and provides basic data on the scale, characteristics, background and occurrence rules of environmental geological problems to illustrate the establishment process of the model. Mine geological environment assessment is a quantitative and qualitative evaluation carried out on the basis of field investigation. It takes into account the complexity of geological environment background and the degree of restoration of mine environmental problems, weighs a number of mine environmental indicators, and evaluates the harm degree of problems and the impact of mining activities on the environment. Therefore, it plays a guiding role in the application scope and application objects of the restoration model. The collection of mine environmental restoration cases is the basis of the extraction and sublimation model, which is helpful to discuss the benefits and effects of the model. There are great differences in the remediation methods for similar mine environmental problems in different regions. Therefore, the remediation and governance cases become the best test method for the pertinence and universality of the remediation and governance model.