Predicting Discharge In Southern Area Of Sijiaying Iron Mine

The hydrogeological condition in southern area of Sijiaying iron mine is complicated, which is not clear in the pre-mining. Many shafts are affected by yielding water, resulting project delays.Therefore, it is of great significance to determine the hydrogeological conditions of the mining area and discharge forecast for mines production guidance, mine safety, water prevention and control schemes determining.The paper has identified aquifer type and boundary condition by interpreting porous pumping test data via time-drawdown and time-drawdown rate curves which use Aquirfer Test software. On this basis identifying hydrogeological parameters; through analysis of the groundwater dynamic data, accurately dividing the hydrogeological units and determining hydraulic connection, the water filling conditions, then,fully understanding the complexity of hydrogeological conditions in the south of Sijiaying; investigating the roadway construction of each shaft, normal drainage and water inrush of mine; through generalizing water system and drainage system, established the hydrogeological model of three-dimensional transient flow, using numerical, analogy and equilibrium method to predict the water inflow in different mining segments.Interpretation and analysis results show that the regional water control structure of Sijiaying iron mine in the southern area has developed. The type of aquifer exsits the character of region zoning. The aquifer is divided into the Quaternary upper strong aquirfer, low of quaternary, weathering fissure aquifer, structural fissure aquifer according to aquifer medium. In vertical, the”skylight” is the channel that contact quaternary water with weathering of bedrock fissure water, the structural fracture zone is a water filled channel that contact the bedrock weathering zone with the construction working face. On the plane, the southern area of Sijiaying iron mine show the division of the center of Tianxing mine, New River fault zone, Dajiazhuang mining. Bedrock aquifers of three hydrological geological units existing low permeability zone weaken the hydraulic connection, only New River fault zone,the structural fracture in the hole CGK03-NK12 has developed, which become the channel that contact each unit. The central area of the Tianxing mine have a shortage of recharge in side and vertical direction, underground water inflow tends to be stable; the New River fault zone is watery strongly, fractured uniform and the pressure of bedrock fissure water transmission is fast, lateral supply good, frequently occurred region of water bursting; Dajiazhuang mining fracture is not uniform, water pressure transmission is obvious between bedrock fissure water and lower Quaternary aquifer water, quaternary transfluence is the main water burst source for Dajiazhuang mine.The south of Sijiaying, aquifer system form a typical complex three-dimensional flow system which has a multi layer structure, aquifers are connected with each other, the boundary conditions and the water structures are complex. By numerical, analogy and equilibrium method, predicting the water inflow in the-250~-450 m level is 6.93×104~11.26×104 m3/d. According to the analysis results, water control should seal mainly under the condition of under pressure mining, "skylight" shallow layer of water should be closure. Then put forward transecting the hydraulic connection between New River fracture zone and southern water rich zone in the hole CGK03-NK12 and important roadway engineering should avoid new river fracture zone.