K d in Screening-Level Ground-Water Contaminant-Transport Model

This paper describes the use of system-specific and literature values for the distribution coefficient ( K d ) in a screening-level ground-water contaminant-transport model. A comparison of observed contaminant transport (Cd 2+ ) in a laboratory soil column with predicted contaminant transport using a computer model is described and discussed. The results indicate that measured K d values and K d values taken from the literature can provide useful approximations of the sorption of inorganic ions in screening-level ground-water contaminant-transport models if experimental conditions (especially pH and electrolyte composition) and soil type are similar to those being modeled.