NAPL Detection Methods

A couple of conventional methods are available to measure the apparent LNAPL product thickness in a monitoring well. The apparent thickness of LNAPL product in a well is typically determined using either a steel tape with water-and-oil-finding 

Drilling Techniques for the Construction and Installation of Monitoring, Recovery, and Injection Wells 

Drilling Technique Geologic Material3 Depth Limitations (ft) Well Typeb Remarks 

Geoprobe U 50 M Geologic and hydrogeologic characterization only excellent sampling and analytical capabilities (soil, 

Hand-augered U 15 M,R water, or vapor) l-in.-diameter well screen capability accessibility excellent Accurate sampling difficult in coarse sediments or loose sand physically demanding fluid levels easily 

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A variety of methods and approaches have been developed over the past decade to address these issues. This chapter takes a look at these methods, and focuses on the occurrence, detection, monitoring, and overall characterization of the subsurface lateral and vertical extent of free-phase NAPLs. Problems and limitations associated with the measurement and determination of apparent vs. actual thickness, empirical and field methods, volume determinations, recoverability, and time frame for recovery are discussed. 

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