Australian-listed FAR Ltd. reports that operator Cairn Energy has been forced to alter its deepwater drilling schedule offshore Senegal due to the need for rig maintenance.

Cairn is currently using Transocean’s Cajun Express to drill the FAN-1 exploration well targeting the North Fan prospect, located in a water depth of 1,427 m (4680 ft) in the Sangomar Deep block about 100 km (62 miles) offshore Senegal.

FAR, which has a 15% equity interest in the drilling program, reports that the rig had reached the 13-3/8-inch casing point in the FAN-1 well, prior to drilling into the two main objectives, but drilling has halted due to essential rig maintenance work that is expected to take approximately 12 days.

As a result the completion date for the FAN-1 well has been delayed, and the estimated cost to complete it is expected to be higher than original estimates. FAR says its 15% participating interest in two Senegalese wells will be covered by future carries from Cairn and another drilling partner, ConocoPhillips.

In early May the Cajun Express was used to drill the tophole section of the FAN-1 well to a depth of 1,200 m (3,936 ft) where it set 20-inch casing and then relocated to spud the tophole section of the SNE-1 well. After setting 20-inch casing at SNE-1 the Cajun Express was to return to FAN-1 to drill the well to its total planned depth.

Offshore