For all remedial investigation and cleanup sites, the vertical and horizontal contaminant profiles should be defined as much as possible. Information on the overall range and diversity of contamination across the site is critical to treatment technology selection. Obtaining this information generally requires taking samples and determining their physical and chemical characteristics. If certain types of technologies are candidates for use, the specific data needs for these technologies can be met during the initial stages of the investigation. The data requirements are technology-specific and not risk-based. The following subsections present a partial list of the characteristics and rationale for collection of treatment technology preselection data for each of the three media. A matrix of characteristics affecting treatment cost or performance versus technologies is provided in Appendix D. This matrix is also an effort by FRTR.