OREANDA-NEWS. May 29, 2007. The drillers of OAO TATNEFT have drilled the second pair of the horizontal U-shaped wells coming out to the surface at Ahalchinskoe bituminous oil field making another very important step on the way of developing bituminous fields in the Republic of Tatarstan, reported the press-centre of  OAO TATNEFT.

The second well pair of horizontal wells as well as the first one has been drilled with application of a conventional drilling rig BU-75 with the vertical depths of 100 and 95 metes respectively. However, the length of the horizontal wellbores along the productive thickness is about 500 meters making it about one and a half times longer versus the first pair of the wells while the total length of the wellbores amounts to 700 meters each.

Unique technologies and technical solutions having no analogues in the world have been tested in the process of drilling the second horizontal well pair.  A successful completion of the most complicated job resulted from the joint efforts of Tatneft's drillers, the scientists of TatNIPIneft, supervisors and many other experts of the Company.

Meanwhile the commercial production of bitumen already on the way from the first pair of the bituminous wells drilled in April 2006. A daily production rate of the high viscosity oil amounts to 15 tons.  It proves possibility of successful application of the steam assisted gravity drainage technology for formation stimulation and development of the natural bitumen fields.

The next stage plans drilling of the third pair of the horizontal wells with the length of the horizontal sections of 550 meters. The total number of the horizontal well pairs envisaged to be drilled at Ashalchinskoe field is expected to amount to 25.