Alkalinity landfill leachate

A more simple treatment is the pH correction, very often used for regulation compliance (the pH value of the treated effluent must be between 5.5 and 8.5). A pH modification can also be used for metallic compound precipitation usually as hydroxide forms, in alkaline conditions, or for humic substances removal, in acidic conditions. The effect of this last treatment can be shown for landfill leachates treatment in Chapter 10. 

Fig. 11.6 Concentration contour plots of the Borden Landfill, Canada, leachate plume with respect to chloride, sulphate, alkalinity (HCO3-) and calcium (Nicholson et al. 1983)...

In principle the material properties identified in Table 1 allow an attenuation liner to be engineered for any given landfill. The ideal liner recipe which maximizes the attenuation of the key contaminants in leachate is deduced to be high clay and organic carbon content plus adequate alkaline pH buffering capacity. 

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