| acamedia.info
by Joachim Gruber
ARTS KUNST
|
acamedia
Geosciences |
|
Contaminant Behavior in the Environment
A summary of my research on contaminant migration A coupled geohydraulic/geochemical transport model is solved numerically. Even when the leakage from a waste repository produces negligible concentrations in the escaping water ("primary leakage"), a considerable contaminant inventory can become associated with the solid phase of the porous medium ("secondary repository"). A simple process is shown to be able to both remobilize that secondary repository and achieve soluble contaminant concentrations far in excess of those in the primary leakage.
I hope you'll find the above papers helpful. They seem quite exotic in environmental geochemistry, and I'll be happy to help you when you think you have problems in following the formalism. Also, have a look at the research at the Dept. of Petroleum Engineering, School of Earth Sciences, Stanford University, Stanford, CA 94307, USA, e.g. at Analytical Multicomponent Displacements by Birol Dindoruk and Lynn Orr's research on carbon dioxide injection into deep geological formations. A coupled geohydraulic/geochemical model shows that waste components may accumulate during migration from the repository. Geochemistry puts upper limits to the concentrations of natural elements in biosphere compartments, and thus also the degree of the mentioned accumulation (after the long-lived radioisotopes have become geochemically indistinguishable from their naturally occurring stable isotopes). When those upper concentration limits are below the permissible concentratons -defined by the International Commission on Radiological Protection- the natural geochemical isolation might be considered sufficient and no further man-made containment of the waste element necessary. Nickel is chosen as an example of a dominant radioisotope.
The Baltic Sea is continuously being fed with large amounts of contaminants. They adsorb to the particulate matter suspended in the sea water. This particulate matter is constantly generated and settling onto the sea bed. This way the contaminants are continuously being removed from the mobile phase of the Baltic ("sedimentation"). If one knows the particulate removal rates one can -on the basis of a balance between feed and removal- calculate the stationary mobile contaminant inventory as a function of the parameters determining the settling process. The presented research shows a method to determine the particulate removal rate. |