A PES Study of Factors Influencing Metal Partitioning in Aquatic Systems “Design of Experiment As, Cd, Co, Cr, Cu, Pb, Ni, and Zn”
Eid A. Alkhatib, John Rapaglia, Leon Theim
Abstract
Mobility and bioavailability of heavy metals are related to their partitioning amongst suspended sediment and
water. A Particle Entrainment Simulator (PES) is used to simulate sediment resuspention in natural surface water
systems. The simulations were carried out under various conditions of water/suspended solids conditions. Five
factors, each at various levels, are tested collectively: the pH of water at two levels (4 and 8), shear stress on
bottom sediment at three levels (0.1, 0.3, and 0.5 N/m2) salinity of water at two levels (0.01 and 14.0 ppt), organic
matter in sediment at three levels (0.50, 1.93, and 3.80%) and temperature at three levels 6, 15, and 30oC). The 33
x 22 factorial experiment was generated using Mini Tab 16® software. The metals evaluated in this study are the
top eight metals commonly found in New England sediments. Each metal concentration was simulated at a level
slightly higher than its Effective Range Median (ERM), above which, detrimental effects are frequently observed
when exceeded. For the eight metals tested in this study, multiple regression equations are generated to predict
the partition coefficient Kd of each metal under the various conditions of the five factors studied. The most
significant factors influencing partitioning of each metal and the interactions between the factors were evaluated
and validated.
Full Text: PDF