Waste soil and residue induced by project construction is one of the main ground materials.Based on field scouring experiment

the processes of runoff and sediment yield on waste soil and residue in the Banduo hydropower station project area in the Yellow River were studied and following results were obtained.(1)Under different flow rates

runoff yield varied with souring time and the relat ionships can be described by power equations.Runoff yield changed great ly in initial 5 m in

then changed slowly

and tended to be steady eventually.(2)Under different flow rates

sediment yield decreased with souring time and the relationships can be described by logarithmic equations.(3)Under dif ferent flow rates

sediment concent ration varied with so uring time and the relationships can be described by logarithmic equations.The variations for different flow rates had the same trend

basically.(4)Depth of single runoff yield and modulus of single sedi-mentyield increased with different flow rates and can be described by logarithmic equations.The averaged sediment concentration varied with so uring time and the relationship can be described by a parabola equation. Critical flow rate was found to be 7.17 L/min.(5)The relationship between depth of single runoff yield and modulus of single sediment yield showed a positive correlation.Modulus of single sediment yield increased with depth of single runoff yield and the relationship can be described by a logarithmic equation.