Another attempt is being made to put out a fire deep below the surface at Guernsey's landfill rubbish tip.
Other attempts to extinguish the fire, which has been smouldering at Mont Cuet for almost three years, have failed.
One of the major difficulties in the past has been pinpointing the exact location of the fire.
Now specialist engineers will drill boreholes up to 35m (115ft) into the waste to allow temperature probes to build up a profile of heat levels.
Tests in December recorded temperatures of up to 70 degrees centigrade at the core.
Experts say the fire does not pose a significant health and safety risk, but if left unchecked there is a danger the rubbish mass within the former quarry could become unstable.