Simulating fate and transport of chromium in saturated sediments

A mathematical model has been developed to improve our understanding of how the transport and bioavailability of chromium are affected by complex sets of microbiological and geochemical reactions. Simulations are performed to illustrate the effect of biotic and abiotic reactions on the fate and distribution of chromium in a saturated sediment and to identify the key process of the reductive transformation of Cr(VI). The results showed that chromium transport and bioavailability could be greatly affected by microbially mediated Cr(VI) reduction. The distribution of chromium in sediments was relatively insensitive to abiotic reaction parameter changes but was sensitive to biotic reaction changes. Because of the finite capacity of biological Cr(VI) reduction, transformation of Cr(VI) into Cr(III) can be most effective in the remediation of chromium contamination under the optimal Cr(VI) concentration and remediation duration.