The Stage II Preliminary Site Investigation or Phase II Environmental Site Assessment is the second step of the environmental site assessment process. The scope of work for this type of an investigation is intrusive in nature involving sample collection of various matrices (soil, groundwater, air, etc.) and a chemical analysis program. The main objective of the study is to confirm or refute the conclusions of the Stage I PSI study. The scope of work required to complete the Stage II PSI may include sampling and chemical analysis of the subsurface soil and groundwater in order to determine the extent of potential contaminants at the site. This information is utilized to determine if the site is contaminated and whether further work is warranted. In addition, the information helps estimate the volume of any contaminated soil/groundwater. The sampling and chemical analysis program is based on the existing and historic use of the site and vicinity and is usually defined by the Stage I PSI study. The targeted contaminants of concern are based on the potential sources of contamination.
The samples of subsurface soil are collected from auger holes advanced at strategic locations around the site to depths determined by the type of contaminant and soil geology. The groundwater samples are collected from the monitoring wells installed in auger holes advanced for soil sampling.
Our staff routinely conduct Stage II PSIs at simple and complex sites with a wide range of land uses and activities involving different types of contaminants. Our experienced personnel have the knowledge and experience to ensure that the investigations are comprehensive yet focused in order to minimize costs.