The attenuation properties of the clay samples considered and evaluated were hydraulic conductivity, permeability characteristics and geochemical properties (pH,OMC,CEC,Iron Oxide and AEC). Attenuation results were analyzed in conjunction with that of Total and WAD CN obtained from field leaching tests at five sites. Low hydraulic conductivity and a combination of low acidic pH, relatively high AEC and low CEC were identified to be the major driving attenuation properties that favour cyanide attenuation. The average concentration of Total CN concentration detected within a radius of 3m is 0.02 mg/l, constituting 99.9% attenuation of CN introduced. The hydraulic conductivity and permeability values computed from grain size analyses of the sub-strata material are 6.2 x 10-3to 1.4 x 10-2m/day and 6.1 x 10-12 to 1.39 x 10-11m2 respectively. The TSF sub-strata material has a pH range of 4.3 to 4.8, a CEC range of 1.92 to 2.89 meq/100g and an AEC range of 881.25 to 1278.25 meq/l. The attenuation rate of CN at the five (5) stations remained constant at 0.021 mg/l/hr as time increased. This book is targeted at mining industry professionals and academia.