Methods and systems for quantification of NAPL transmissivity

A method of evaluating a distribution and a recoverability of a dense non-aqueous phase liquid (DNAPL) comprising:

• testing a transmissivity of the dense non-aqueous phase liquid (DNAPL), wherein the testing the transmissivity of the dense non-aqueous phase liquid (DNAPL) comprises:
• placing a first transducer in the dense non-aqueous phase liquid (DNAPL);
• recording a first pressure measurement from the first transducer;
• calculating an elevation of the dense non-aqueous phase liquid;
• placing a second transducer in a water column near the dense non-aqueous phase liquid (DNAPL);
• recording a second pressure measurement from the second transducer;
• calculating an elevation of the water column;
• and
• comparing the elevation of the dense non-aqueous phase liquid (DNAPL) to the elevation of the water column to determine a thickness of dense non-aqueous phase liquid (DNAPL);
• determining a mobile interval definition of the dense non-aqueous phase liquid (DNAPL), wherein the determining a mobile interval definition of the dense non-aqueous phase liquid (DNAPL) comprises:
• measuring a first specific gravity of the dense non-aqueous phase liquid (DNAPL);
• measuring a second specific gravity of a water column;
• and
• performing a calibration using the first and second specific gravity measurements;
• integrating the definition into a conceptual site model;
• and
• quantifying a recoverability of the dense non-aqueous phase liquid (DNAPL),
• wherein a subsurface for recoverability comprises a fractured porous media or a layered arrangement of granular porous media and non-porous media.

A method of evaluating a distribution and recovery of a non-aqueous phase liquid (NAPL) in a subsurface comprising:

• identifying a plurality of mobile non-aqueous phase liquid intervals (MNI) in the subsurface, wherein the identifying comprises:
• removing an amount of non-aqueous phase liquid (NAPL) from the subsurface through a well, wherein the amount of non-aqueous phase liquid (NAPL) removed is substantially all the non-aqueous phase liquid (NAPL) from the well at an equilibrium condition;
• monitoring an apparent drawdown of the non-aqueous phase liquid (NAPL) in the well;
• monitoring a discharge rate of the non-aqueous phase liquid (NAPL) in the well from an area of the subsurface comprising non-aqueous phase liquid (NAPL) near the well;
• analyzing a rate of change for the discharge rate;
• analyzing a rate of change for the drawdown;
• and
• determining when the rate of change for the discharge rate and drawdown are substantially zero;
• determining a transmissivity of a non-aqueous phase liquid (NAPL) in the subsurface wherein determining comprises gauging the subsurface with at least one of a pressure transducer or an electronic interface probe;
• and
• quantifying a recoverability of non-aqueous phase liquid (NAPL) in the mobile non-aqueous phase liquid intervals (MNI).