In cold climates, insulating a septic tank may be necessary to maintain the internal tank temperatures necessary for active digestion and even to prevent freezing of the liquid. As the temperature drops in the tank, the natural bacterial activity drops as well and becomes dormant as temperatures drop below 40 degrees F. Tank walls, lids and risers may all require insulation, and a number of options are available for this purpose. All insulating materials must be resistant to water absorption.Insulation board can be placed along the side and on top of the tank prior to backfilling. When selecting a board,
