Tullow Oil said the Awaka-1 exploration well, located in the Butiaba region of Uganda Block 2, has been plugged and abandoned after only encountering water bearing reservoir sands."Although we are disappointed to encounter our first failed trap in a highly successful 23-well campaign, the Awaka-1 well has located a thick new sand fairway which may have significant follow-on potential," said the group.It said in the short to medium term its exploration drilling campaign will focus on the core of the Victoria Nile Delta play and on penetrating the target reservoirs in the large Ngassa prospect.Information gained from the Awaka-1 well will now be used to establish additional leads in this region, it said.Elsewhere in Block 2, the Ngassa-2 exploration well has been drilled to 2,230 metres and is expected to penetrate the reservoir sections encountered in the Kasamene and Kingfisher wells within the next month.