Investigating the Potential for Long-Term Permeable Reactive Barrier (PRB) Monitoring from the Electrical Signatures Associated with the Reduction in Reactive Iron Performance

Slater, Lee

Rutgers University, Newark, NJ (United States)

关键词: Precipitation;    Oxidation;    Surface Area;    Monitoring;    Electron Exchange;   

DOI  :  10.2172/838635
RP-ID  :  EMSP-88615--2003a
RP-ID  :  FG07-02ER63508
RP-ID  :  838635

美国|英语

来源: UNT Digital Library

【 摘 要 】

The objective of this project is to quantify the ability of the electrical induced polarization (IP) method to non-invasively monitor the reduction in reactive iron performance that is known to reduce the effectiveness of the permeable reactive barrier (PRB) with time. The primary scientific goals include: (1) fundamental laboratory studies to evaluate the sensitivity of the IP method to: Fe0 total surface area Fe0 surface chemistry physical/chemical changes to the Fe0 surface resulting from oxidation and precipitation (2) monitoring of the electrical tomographic response of the Kansas City PRB over a three-year period and assessment, via correlation with aqueous geochemical data and extracted iron cores, of whether electrical signatures associated with reduced PRB performance are resolvable in field studies (3) optimization of a three-dimensional tomographic imaging algorithm for application to highly conductive, high electrical contrast environments as represented by a PRB IP theory and empirical data resulting from the original development of the method for mineral exploration suggests that the method is highly relevant in the study of reactive iron barriers. Laboratory and field IP studies on mineral deposits illustrate the sensitivity of IP parameters to metal concentration, particle size and metal surface chemistry. IP theory, based on electrical (Warburg) impedance associated with diffusive ion transfer to/from the electrolyte to electron exchange sites on the metal surface, provides a framework for interpreting IP signatures of PRBs as a function of redox chemistry.