Sites impacted by petroleum hydrocarbons, in particular, free-phase petroleum in the subsurface (light nonaqueous phase liquids/LNAPL), represent a significant proportion of existing contaminated land inventories. Poorly planned and executed site characterizations will likely result in additional project expense during the investigative phase and subsequent remedial actions, and may provide inadequate or misleading data, which can result in an increased risk to human health and the environment. “Traditional” characterization methodologies often are unable to adequately identify controlling in-situ heterogeneities, leading to significant errors in the estimation of the quantity and spatial distribution of LNAPLs in the subsurface.
High-Resolution Site Characterization (HRSC) are strategies and methodologies that use scale-appropriate measurements and sample density to define contaminant distributions, and the physical context in which they reside, with greater certainty, supporting faster and more effective site cleanup. The use of HRSC can improve the management and remediation of LNAPL-impacted sites and reduce long-term costs associated with cleanup and closure. Several innovative direct-push technologies have been developed, which can provide qualitative or semi-quantitative results in real-time and also identify the hydrostratigraphic/hydrogeologic environment in which they reside. When used over an extended area, they can provide a three-dimensional characterization of contaminant distribution.
Primary Author / Conference Presenter:
Environmental Services Manager
San Leandro, California, USA