Casing Programme Print

The Barbados National Oil Company (BNOC) uses drilling mud for lubrication when drilling wells, however no lubricating mud is used when drilling through the limestone. When the base of the limestone is reached, a water based drilling mud is used to drill through the underlying formations.

The precaution undertaken to prevent the contamination of the groundwater in the formation and surrounding areas is the implementation of the casing programme. The BNOCL uses internationally accepted casing standards and a strict casing programme is followed for all of the oil wells drilled in Barbados.

It has been agreed by the regulating authorities that no new wells in Zone 1 are to be drilled (Zone 1 is a water protected area). Furthermore, a double casing programme was followed for all of the existing wells in these areas. In the double casing programme, cast iron casing of two (2) different sizes are used. The smaller casing is placed within the larger one and cement is placed between the two (2) casings and between the larger casing and the wall of the borehole that no new wells will be drilled in Zone 1 and Zone 2 area catchments which are protected zones.