Gran Tierra drills Costayaco-2 in Columbia

Gran Tierra Energy Inc. has initiated drilling Costayaco-2 in the Chaza Block, located in the Putumayo Basin of southern Colombia.

Costayaco-2 is the first of two delineation wells that will be drilled in the Costayaco field. Drilling is anticipated to take approximately one month with completion and testing operations to follow. The second delineation well, Costayaco-3, will be drilled in the first quarter of 2008 following completion of Costayaco-2.

The Costayaco oil field was discovered in the second quarter of 2007. The discovery well, Costayaco-1, tested a maximum of 5,906 barrels of oil per day (bo/d) from four reservoirs. The well has recently been producing approximately 2,200 bo/d from a single zone on natural flow with production trucked to the nearby Toroyaco facility. During this period, infrastructure at Uchupayaco, to handle new production, has been under construction. Testing of a jet-pump that will commingle production from two zones is currently under way.

Crude oil loading and unloading facilities for trucking operations from the Costayaco field to the existing pipeline network at Uchupayaco have been completed and trucking to this facility initiated. Planning for a 15-kilometer 8-inch production line from Costayaco to Uchupayaco is continuing. Construction of the production line is scheduled to start in March, 2008, and be completed in mid-2008.