Abstract: A method for development drilling in a mineral producing field such as an oil and gas field wherein a plurality of wellbores are drilled in the earth through at least one mineral containing subsurface geologic formation, the plurality of wellbores being drilled from a central drill site radially outwardly therefrom wherein the wellbores are drilled at varying angles from vertical within the range of from about 30 to about 87.5 degrees from vertical, the wellbores passing through at least one formation at an angle from vertical.

Abstract: A method for completing a well whose wellbore passes through a permafrost zone, the wellbore having at least one annulus in the permafrost zone, the annulus initially containing a freezable liquid. In the method openable and closable apertures are disposed near the bottom of the permafrost zone for achieving access between the interior of the wellbore and the annulus. Using these apertures, a hard collar, for example composed of cement, is emplaced in the annulus in the vicinity of said apertures. Thereafter the freezable liquid is displaced from the annulus above the collar using an essentially nonfreezable liquid which can be left in the annulus in the permafrost zone for the life of the well.