EXPERIMENT OF HYDROGEOLOGY PARAMETERS IN THE YONGDING RIVER

The in-situ hydrogeological test is a variety of experiments which is indispensable in a hydrogeological investigation in order to obtain the hydrogeological parameters and find out the groundwater movement conditions. In recent years, human activities and urban development changed the hydrogeological conditions of riverbed in Yongding River, followed by the changed hydrogeological parameters. In this paper, different hydrogeological parameters of the Yongding River bed are obtained by six double-ring infiltration tests, two percolation pit tests, four pumping tests. It was found that, the vertical average permeability coefficients of the exterior and the middle of the surface river bed are 2.155md-1, 1.469md-1, 0.557md-1 and 0.3865md-1,respectively. The permeability coefficients of the deep layers of the Lianshi Lake and the thermal power plant were 5.92md-1, 2.68md-1.The permeability coefficients of Zhaocun, Efang, Lugou Bridge and Lianshi Road were 10md-1, 28md-1, 70md-1, 124md-1,respectively. According the dispersion test conducted in the section of the Lugou Bridge of Yongding River, the longitudinal dispersion coefficient(DL),actual groundwater flowrate(U) and dispersion degree(a) are 0.772m2h-1, 0.146mh-1 and 5.287m, respectively. The acquisition of hydrogeological parameters under the present conditions provides an important basis for groundwater resources calculation and evaluation, groundwater numerical simulation and forecasting, groundwater exploitation, protection and scientific management, and provides support for the construction of the green ecological development zone in Yongding River.