SwelLCM® , a patented product developed by Turbo-Chem International, Inc., when used ahead of the cement can substitute as a spacer & can assist in solving cement lost circulation.SwelLCM® can be used ahead of or in the middle of the cement job to ensure returns to surface or the lap of a liner. SwelLCM® , a pH reacted material, expands to fill in voids or fractures and diverts the cement up hole preventing it from being lost to these thief zones. It has been used successfully ahead of cement, for a top set job, to fill the annulus to surface, between drive pipe and surface pipe. Three prior cement jobs were lost to a thief zone in the surface hole. The SwelLCM® was pumped ahead of the cement on the fourth try and the cement remained in place until it hardened and bonded.