Abstract: In a method wherein two or more separate zones in a single wellbore are subjected to a consolidation treatment to prevent the production of solid particles from those zones into the wellbore, a tracer material is incorporated into each zone which is subjected to the consolidated treatment, the tracer material being unique to that particular zone. Thereafter, fluid produced from the well is analyzed to determine if any and, if so, which zone or zones are still leaking solid particles into the well. Subsequent consolidation retreatment of the well is then limited to the zone or zones indicated to be leaking solid particles rather than being applied to all zones in the well again.