In this paper, a new set of measurements is presented to investigate the relationship between the hydraulic and electromagnetic properties of the Arctic permafrost active layer soil, which includes high organic matter content. Low-frequency dielectric permittivity and the soil water matric potential have been measured for over 50 soil samples collected from northern Alaska for a full range of soil moisture value. The organic matter content is included as a new input parameter and the hydraulic properties of soil have also been taken into account. The result is a new dielectric mixing model for soils containing organic matter and surpassing the range of validity of other existing models.