Practice question

Bioslurping represents hybrid technology merging vacuum-enhanced free product recovery with bioventing to address sites where light non-aqueous phase liquid LNAPL such as gasoline, diesel and jet fuel accumulates as floating layer 2 to 100 centimeter thick on top of water table, serving as persistent secondary source dissolving into groundwater. Technique deploys adjustable slurp tube inside well connected to high-vacuum blower generating 20 to 30 inches mercury, extracting groundwater, free-phase hydrocarbon and soil vapor simultaneously through same conduit via Venturi effect; liquid rises into knockout separator where LNAPL skimmed for off-site recycling or disposal while water treated via air stripping or carbon adsorption. High vacuum expands capture zone radius 10 to 30 feet enhancing mobility of floating product toward extraction well through increased hydraulic gradient. Concurrent soil gas extraction induces airflow through smear zone stimulating aerobic biodegradation of residual sorbed phase via alkB bearing microbes, polishing source zone after bulk liquid removal. Unlike heavy metal or chlorinated solvent DNAPLs denser than water, floating hydrocarbons uniquely amenable because they reside at air-water interface accessible to slurp tube. Pilot tests measuring transmissivity and product thickness determine viability versus dual-phase extraction.