Cap,

why not trap the soil CO2 in an alkaline solution rather than 
freezing everything? That should avoid all the problems with 
hydrocarbons. This technique has been used by quite some people, 
and has been continuously improved over the years. It also has 
the advantage of easy CO2 storage for a long time as precipitated 
carbonate.

Cheers,

Frank








----------------------------
Frank Pawellek
Stable Isotope Laboratory
Department of Geography
University of Wales, Swansea
Singleton Park
Swansea SA2 8PP
Wales / GB

Tel. +44 1792 295148
Fax. +44 1792 205556
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