Site Characterization

The Manual and Reports on Engineering Practice Number 99 published by ASCE titled "Environmental Site Characterization and Remediation Design Guidance" was completed by the Environmental Engineering Division, Remedial Investigation/Feasibility Study/Remediation Design Manual Task Committee in 1999. This paper provides a summary of information contained within the "Site Characterization" Chapter of the Manual. Site characterization is one of several phases of an investigation and cleanup program for a given location. Before embarking upon the evaluation of remedial alternatives, it is important that the site be adequately characterized. A poorly characterized site could result in delays and other problems during remediation implementation. Before carrying out a site characterization, the investigator must first identify the purpose and define the scope of the investigation. Available background information is reviewed to focus the characterization and assist in the interpretation of data. Information to be considered as part of the planning process includes site history, physical features, and contamination source characteristics. Methods for obtaining site characterization data can be evaluated in terms of practicality, economics, simplicity, versatility and safety. Methods commonly used for obtaining and analyzing samples to characterize soil, surface water, groundwater, and air are presented. Methods presented for collecting soil samples include geophysical techniques, grab soil sampling, hand augering methods, trenching, soil vapor surveys, direct push methods, and drilling. Some techniques for collecting samples of sediment, surface water, groundwater, and air samples are presented. Data obtained as part of the site characterization is reviewed to verify consistency with objectives of the characterization investigation.