as will be observed the relationship between the elapsed time t and the distance d generally follows a non linear curve reaching a maximum distance d m and then decreasing to zero along the horizontal axis with the further passage of time using this relationship it is possible to choose an optimum time t o after a pilot hole of a pre determined diameter is drilled for the purpose of achieving minimum soil resistance to pile driving the invention primarily lies in the utilization of the empirical principles and relationships taught in fig4 and 5 in a new and improved method for driving piles in cold dense permafrost this method begins with drilling a pilot hole usually just short of the design elevation tip of the pile along the desired pile alignment the cross sectional area of the pilot hole is advantageously chosen to be comparable to the cross sectional driving area of the pile when a pile is driven down along the alignment of the pilot hole the soil displaced by the pile is relatively of the same volume as the pilot hole thereby avoiding significant displacement of the immediately neighboring permafrost and undesirable voids a suitable time prior to the driving of the pile dependent upon a the peculiar properties of the local permafrost b the temperature of the water c the cross sectional area of the pilot hole and d the driving area of the pile the pilot hole is filled with water the pile is then driven after an elapsed time calculated a to maximize the distance from the longitudinal axis of the pilot hole at which the temperature of the immediately surrounding permafrost is sufficiently raised by the water and b to minimize the soil 39 s resistance to the pile driving given.