Table 1 Generalised relationships between the environmental conditions, as categorised by pH and Eh, and the mobility of elements (data from [11])
Relative mobility of element | Environmental condition | |||
|---|---|---|---|---|
Oxidising | Acidic (low pH) | Neutral (pH 7)—alkaline (high pH) | Reducing | |
Very high | I | I | I, Mo, U, Se | I |
High | F, Mo, U, Ra, Se, Zn | Co, Cu, F, Hg, Mo, Ni, U, Ra, Se, Zn | F, Ra | F, Ra |
Moderate | As, Cd, Co, Cu, Hg, Ni | As, Cd | As, Cd | Â |
Low | Be, Bi, Pb, Sb, Tl | Be, Bi, Fe, Mn, Pb, Sb, Tl | Be, Bi, Fe, Mn, Pb, Sb, Tl | Â |
Very low (immobile) | Al, Cr, Fe, Mn | Al, Cr | Al, Co, Cr, Cu, Hg, Ni, Zn | Al, As, Be, BiCd, Co, Cr, Cu, Hg, Mo, Ni, Pb, U, Sb Se, Tl Zn |