A major challenge of developing accurate predictive models is understanding the coupled nonlinear physical, chemical, and biological subsurface processes that control the movement and transformation of reactive contaminants and other constituents in heterogeneous vadose zones and aquifers. Fundamental studies of these coupled biogeochemical processes are going on worldwide. Some examples include: chemical speciation, elucidation of micro-organisms metabolic co-metabolicreactions, and biodegradation or immobilization of contaminates.
A number of barriers make it difficult to accurately predict contaminant mobility or to optimize subsurface treatment. Knowledge of equilibrium chemical speciation and sorption reactions does not account for the rates of forward and reverse reactions, or the irreversibility of some reactions (especially adsorption). A related problem is that the rates of mircobially mediated processes observed in the laboratory are generally believed to be orders of magnitude faster than those observed in the field. Possible reasons for this discrepancy are unknown concerning natural ecological structure, mass transfer limitations, and controls on nutrients and contaminant bioavailability.
Other problems include undeveloped contaminants, more expensive tools due to advanced technology, new approaches, not being able to extensively test assemblies, etc.
- Contacts:
- Mark Ankeny, (208) 526-5748, Send E-mail