Distribution coefficients (K d ) were measured for cadmium (Cd) and nickel (Ni) in laboratory batch experiments for 18 sandy aquifer materials at environmentally relevant solute concentrations (Cd: 0.1-15 μg/l; Ni: 4-200 μg/l). The K d -values ranged three orders of magnitude: Cd: 2-1770 l/kg and Ni: 3-7250 l/kg. Correlating observed K d -values to characteristics of the aquifer materials (particle size fractions, organic-C content, surface area, pH) revealed very good correlation with pH in the pH range 4.9 to 8.9 (Cd: r 2 = 0.942; Ni: r 2 = 0.929). Including any other of the measured aquifer material characteristics did not improve the correlation significantly. The results indicate that at the same pH-values, the K d -values for aquifer materials are 4-10 times lower than K d -values for soils reported in the literature. However, the mobility of Cd and Ni, as reflected in the K d -values, is still very limited in sandy aquifers, unless the pH is very low. The results indicate that at pH 6 the relative mobility of both Cd and Ni is of the order of 1%.