From the very start, the amount of material, as well as its relative inaccessibility, made removal a far more difficult task than mere dig out with excavators. Lobbe did a predesign investigation and then designed and implemented a pilot project based on cryogenic technology. Recovering the tar involved injecting liquified nitrogen. The tar hardened, became crumbly, allowing most of it to be removed.

But in the end it turned out that residues in the pits could be cleaned out using conventional removal techniques. Clean-up time, including cleaning of the pit walls, took two months, by working at times in three around-the-clock shifts. Lobbe completed the project and turned over the cleaned facility a week ahead of the projected completion time.