Environmental Soil and Ground Water Assessment Using High Resolution Passive Soil-Gas Samplers - Petrex Method: Methodology and Results of a Case Study Performed in Brazil

The PETREX Passive Soil Gas Technique - applied successfully to environmental projects for 10 years - is the ideal primary investigative tool for soil and groundwater contaminations, since it is rapid, easy to apply and covers large areas. It is more sensitive and cost effective than other methods (e.g. active soil gas techniques). Passive collectors combined with high-resolution mass spectrometry permit direct mid reliable identification of over 9,000 volatile (VOCs) and semi-volatile organic compounds (SVOCs). PETREX is capable of providing comprehensive problem delineation during the initial stages of the site investigation, allowing for greater cost effectiveness in the planning of remediation programs and in the selection of appropriate monitoring well locations and other methodologies which may be needed to complete the environmental evaluation. PETREX therefore finds wide use in the investigation of contaminants, in the determination of pollution sources, as well as in audits connected to real estate transactions. This paper describes a case-study developed in Brazil, showing PETREX's usefulness and its correlation with soil and groundwater contamination plumes established from traditional direct sampling methods.