Flow is over and under permafrost. The sub-Arctic is a vast region with long summer days and exceptionally cold winter nights. But below the surface tempertures range a only a few degrees above and below freezing creating a mosaic of frozen and un-frozen ground. Permanently frozen ground is called permafrost, and the study of subsurface hydrology and contamination transport in northern regions must consider this permanent frozen condition. In Alaska, permafrost north of the 66th parallel is continuous, but south of that latitude it is discontinuous.
Permafrost affects soil percolation and human activities including construction.
For decades, underground hydrology has been studied in more temperate regions, but only recently have researchers looked at how permafrost affects these processes in the Far North. Larry Hinzman is the principal investigator for a project characterizing contaminant transport processes on Fort Wainwright, a U.S. army base near Fairbanks, Alaska. Permafrost and the Migration of Contaminants In 1943, above-ground storage tanks were built on Fort Wainwright near Fairbanks, Alaska. These tanks were used through 1993. Discontinuous permafrost exists between the tank farm and the drinking water wells in a nearby neighborhood.