Light, nonaqueous-phase liquid (LNAPL) management (LNAPL assessment and remediation) presents some of the greatest corrective action and cleanup compliance challenges to petroleum manufacturing, storage, and handling facilities such as refineries, bulk product terminals, gas stations, airports, and military bases The management of LNAPL requires to first identify the specific LNAPL composition and saturation concerns the … Continue reading
The presence of LNAPL and the characterization of LNAPL in the subsurface is often determined primarily by the measurement and observation of LNAPL in monitoring wells. It is noted, however, that the relative measure of apparent thickness of LNAPL in a well, while indicative of LNAPL presence, has been shown to be a poor … Continue reading
The LNAPL Conceptual Site Model (LCSM) is the body of information describing aspects of the LNAPL and site setting necessary to satisfy the LNAPL remedial objectives. The LCSM is similar to a conceptual site model, which includes the source, pathway, and receptors, but the emphasis in the LCSM is on the source component (i.e., … Continue reading
To begin proper management of an LNAPL site, one must first determine the problems or concerns that the LNAPL poses at the site. A complete site characterization and LCSM will help to identify these concerns. Once the concerns are identified, appropriate “LNAPL remedial objectives” are set to eliminate the LNAPL concerns at … Continue reading
Once the remedial action is implemented, monitoring is required to assess the protectiveness and effectiveness of the chosen interim remedial measures (IRM). The type and frequency of monitoring should be based on the CSM developed for the site which identifies the LNAPL type, source and distribution, site specific receptor issues, hydrogeologic influences on LNAPL behavior … Continue reading
