June 22, 1994

The documents in this directory detail a new technique for cleanup of
contaminated soil and groundwater. The process is accomplished in-situ by
the introduction of a biologically active reductant into the contaminated
zone via hollow soil probes. This treatment causes radical changes in the
chemistry of the contaminated system. 

Called "Bio-Anaerobic Reduction and Reoxidation" (abbreviated BARR) this
is a method to create repetitive sequential environments (reducing and
oxidizing) in the proximity of a subsurface contaminated formation. BARR
will theoretically degrade ANY organic contaminant, including halogenated
compounds, such as PCB's. 

This is not strictly "bioremediation". The technique utilizes biological
and physical processes to create radical changes in fundamental
thermodynamic parameters such as the redox potential, pH and temperature
as it builds conditioned biomass with the ability to grow in the presence
of the target pollutant. This increase in biomass decreases the specific
toxicity of the pollutant. Thermodynamic gradients are used to destabilize
the target chemicals in the presence of diverse enzymatic catalysts. 
Indirect metabolism, or "cometabolism" is relied upon to transform
pollutant compounds into reactive states that can be ultimately
mineralized.  The redox environment is manipulated in a cyclic manner by
alternate introductions of reductant and oxidant; repeatedly. This
dissolves and reforms many of the soil minerals (chiefly iron and
manganese), to create a high surface-area, biocatalytic matrix. 
 
This process is currently undemonstrated, but the feasibility is widely
supported by the current literature and common knowledge. It capitalizes
on existing technology and offers a new hope for in-situ remediation
of contaminated soil and groundwater. 

There are three parts to the documentation presented here. 
A Report, a Technical Appendix and a Bibliography. 
Please retrieve all three documents. Please do not fragment or edit any 
material to be distributed. Please credit the Author.

The Report contains a description of the process and provides relevant
information to support the actual implementation of the process. The 
Report also describes a novel technique for contaminant isolation using a 
slowly biodegradable wax layer which is injected as a heated liquid and 
becomes solid at ambient temperature.

The Technical Appendix provides fundamental background and explains much
of the terminology and concepts assumed by the Report. 

The Bibliography provides background and relevant literature citations. 

The Report is a somewhat speculative foray into technological
possibilities, based on current knowledge. This is not a report of
research results, it is rather a "synthetic information" document produced
from collected knowledge and creative intuition. 

For information about the Author, get the document "About the Author" in
this directory, or request info via email. 
Larry Dieterich
Internet address is water@well.sf.ca.us. 
Mailing address is 405 E 7th St. Davis, California, 95616 USA 
Telephone 916-758-9260. 

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