Overcoming Obstacles in Phase II Environmental Site Assessment


Overcoming Obstacles in Phase II Environmental Site Assessment

Each Phase II Environmental Site Assessment (ESA) is unique and often requires the use of multiple assessment techniques in order to achieve the objectives.  Dependent upon the Phase II ESA objectives, the collection of soil and/or groundwater samples is often difficult.  Obstacles typically encountered during Phase II ESA activities include, but are certainly not limited to subsurface utilities (e.g. natural gas, sewer, electric), overhead or nearby powerline concerns (arc sparking), heavy vegetation, variable topography, or the presence of structures in the areas to be assessed.  In many cases, environmental consulting firms are unable to collect samples in suspect areas of a property, which were identified as environmental concerns during the course of the preceding Phase I ESA.

As shown in the photograph for this discussion, access limitations (width and height) resulted in the inability to utilize typical soil boring equipment, such as a track mounted Geoprobe.   Prior to choosing this boring location, as with all Phase II ESA boring locations, the required utility locate was called in and significant document review and research was performed.   The in-depth review of building plans, such as blueprints and as-built drawings, was conducted in an effort to mitigate the potential for impacting subsurface utilities or impediments.  In addition, the review of building plans was conducted to identify a foundation depth that could be penetrated with the limitations of a portable concrete coring device.

Without the option of direct push or heavy auger machinery, we cored the 10-inch concrete foundation and then used a hand auger in an attempt to reach the target depth for the soil sample, while constantly screening the excavated soil for evidence of contamination with a photoionization detector.   During the hand auger activities, an area of concrete spoils was encountered at approximately five feet below the foundation.  Although this subsurface obstruction was not identified on the building plans or known/reported by the building owner, it is not uncommon to encounter limitations as a result of variable techniques or deviations utilized during the initial construction or renovation of a building.

To borrow a common phrase, the best laid plans of mice and men often go awry.  No matter how carefully a project is planned, unforeseen issues often exist and are encountered.   As with all Phase II ESAs conducted by Farmer Environmental Group, Plan B is put into action when needed in order to complete the objectives.