Finger heaters are used to heat water in a well just below the Free Product.

The Heavy LNAPL skimmers were developed for recovery of high viscosity floating oils like #6 fuel oil, bunker sea fuel oil, PCB oil, and very old #2 fuel oil.

 

High viscosity Free Product recovery is difficult and slow. Steaming the formation has helped move this type of product to extraction wells but at a very high cost, plus a lot of the Free Product ends up in the dissolved state.