A Phase I ESA (Preliminary Environmental Site Assessment in Brazil) is a report prepared for a real estate property that identifies potential or existing environmental contamination liabilities. The actual sampling of soil, air, groundwater and/or building materials is typically not conducted during a Phase I ESA. The Phase I ESA is generally considered the first step in the process of environmental site assessment. If a site is considered contaminated, a Phase II environmental site assessment may be conducted, a more detailed investigation involving chemical analysis for hazardous substances and/or petroleum hydrocarbons. Anyway, within a few years the increasing popularization of some measuring devices may improve the Phase I ESA, making it more than a query to documents and visual observation.