1.0.1 This code was formulated in order to implement each law and regulation and policy of national development coal industry, promote and apply tried and true advanced technology and management experience of open pit mine, promote the scientific and technical progress, maintain the sustainable development of coal industry, improve the economic benefit of open pit mine, and achieve safety production and rational exploitation of coal resources.
1.0.2 This code is applicable to the pre-feasibility study, feasibility study and engineering design for the construction, renovation and extension of large and medium open pit mines. The pre-feasibility study, feasibility study and engineering design of small open pit mines may be carried out referring to this code.
1.0.3 For the constituent of open pit mine construction engineering project, the major works shall be the first and the principles of coordination based on specialization and socialization service shall be insisted.
1.0.4 For the engineering design of open pit mine, the economic benefit shall be the focus, and the sustainable development principle shall be put into effect, the high-yield and high-efficiency are the target, modern technical equipments shall be adopted, the informatization management shall be carried out and the policy of centralized production and environment burden reduce shall be put into effect. The engineering relation between short-term and long-term and short-term as the first shall be treated well.
1.0.5 For the pre-feasibility study and feasibility study of open pit mine, the necessity, feasibility and reasonableness of open pit mine construction shall be analyzed and researched comprehensively according to excavation field resource conditions, outside construction conditions, possible adopted exploitation process, technical equipments, groundwater control methods and market demand, financing and investment effect.
1.0.6 The policy of comprehensive utilization must be put into effect for the engineering design of open pit mine to effectively utilize resources and protect resources. The paragenetic and associated mineral resources shall be recycled or protected.
1.0.7 For the engineering design of open pit mine, the environmental protection engineering, soil and water conservation engineering and land reclamation project must be designed with main engineering together.
1.0.8 Except for the requirements stipulated in this code, those in the current relevant standards of the nation also shall be complied with for the pre-feasibility study, feasibility study and engineering design of open pit mine.
2 Basic Provisions
2.1 Exploitation Ambit
2.1.1 The economic stripping ratio of open pit mine shall be determined according to such conditions as occurrence of coal seam, capping characteristic, coal quality, technical equipments, resource recovery, production costs and product sale price and shall meet the following specifications:
1 The economic stripping ratio of lignite, mill coal and coke should respectively not be larger than 6m3/t, 10m3/t and 15m3/t;
2 The economic stripping ratio shall be calculated according to the product sale price for exploiting the lower heating coal with lower economic value;
3 The economic stripping ratio shall be calculated according to the comprehensive value for exploiting the open pit mine with multiple valuable minerals.
2.1.2 The openwork ambit shall be determined according to ambit stripping ratio less than or equal to economic stripping ratio. The open pit mine with coal seam occurrence condition and complicated topography shall be checked according to average stripping ratio.
2.1.3 For the engineering design of open pit mine, the feasibility of combined exploitation with open and mine may be considered according to the actual conditions of mines.
2.1.4 The coal pillar ambit shall be set up between openwork ambit and adjacent mine exploitation ambit.
2.1.5 The floor area of excavation field should be determined according to the final ground ambit of exploitation exceeding 50m. If there are such facilities as transmission line, communication line, road, dewatering hole and pipe network and anti-drainage, the corresponding width may be increased according to requirements.
2.2 Resources/Reserves
2.2.1 The pre-feasibility study of open pit mine shall be carried out according to approved detailed survey or open excavation field geology exploration report, the feasibility study and preliminary design shall be carried out according to approved open excavation field geology exploration report, and the design assessment shall be worked out according to exploration degree, resource reliability, coal quality condition, engineering geology, hydrological geology and economic significance.