Abstract: Disclosed is an apparatus for completion of a well. The apparatus includes a tubular configured to be disposed in a wellbore penetrating the earth where an annulus region is defined between an exterior surface of the tubular and a wall of the wellbore. The apparatus further includes a plurality of sensors disposed in the annulus region and configured to sense hydrocarbons during cementing of the tubular to the wall of the wellbore. A receiver is disposed remote from the wellbore and configured to receive measurement data from the plurality of sensors and to provide an indication if hydrocarbons are sensed in the annulus region.