to provide a cement sheath 42 isolating the horizontal target section within formation 12 penetrated by borehole 32 from any overlying water bearing formations incompetent formations or non target sections within formation 12 that may be prone to gas or steam coning the upper end of the lower lateral liner string 36 and some cement initially extends into the vertical portion of well 10 this protruding portion of liner string 36 and cement within the vertical portion of well 10 is removed using a full gauge burning shoe wash pipe fishing tool assembly not shown sized only slightly less than the inside diameter of production casing string 18 to leave a relatively smooth entry opening at the junction of the lower lateral completion 24 and the vertical portion of well 10 the resulting lower drainhole opening or liner window 46 has an elliptical shape with an apex 60 at the top and an apex 64 at the bottom of the window 46 due to the high angle of the lower lateral liner as it meets with the vertical portion of well 10 schematic of fig1 is not drawn to scale or in realistic proportion the lower lateral liner string 36 located adjacent to window 46 preferably includes one or more joints of liner made of a more drillable material than steel ie carbon glass and epoxy composite material to facilitate the removal of said protruding portion of liner extending into the vertical portion of well 10 using a drilling and completion method similar to that described for the lower drainhole completion 24 an upper drainhole completion 22 may be drilled and completed the upper drainhole completion 22 is comprised of a lateral borehole 30 a lateral liner pipe string 34.