(Sharecast News) - Block Energy rose on Wednesday after beginning sidetrack operations in the existing 16a wellbore at its West Rustavi field in the Republic of Georgia.The works on 16a are part of an initial two-well horizontal sidetrack drilling programme at which the company is targeting combined gross production of 650 barrels of oil per day (bopd) from the proven Middle Eocene formation before the end of June.Works follow December tests that retrieved over 200 barrels in the space of 10 hours from the previously producing reservoir, confirming that it is still an active hydrocarbon system and remains pressurised.Paul Haywood, chief executive of Block, said: "With gross contingent resources of 38 MMbbls of oil, a total of six historic wells identified as suitable candidates for sidetracking, and a legacy gas discovery, the potential for West Rustavi to generate significant cash flow and value for Block is clear."Block currently holds a 25% working interest in West Rustavi, which has an estimated 38 MMbbls of gross contingent resources of oil, according to a report from Gustavson Associates, and stands to increase its interest to 75% upon completion of the two-well sidetrack programme as part of an agreed earn-in.The AIM traded company said that four other wells have been identified at West Rustavi offering similar opportunities for re-entry and sidetracking."With back-to-back drilling planned at West Rustavi and multi-well workovers underway at Norio, we expect the strong momentum behind the company to continue as we focus on hitting our H1 2019 target of 900 bopd," said Haywood.In a statement, the company also announced the departure of finance director Serina Bierer, who is stepping down with immediate effect "to concentrate on her other work interests" after giving "a significant contribution" to the company's IPO and annual report.Block Energy's shares were up 4.18% at 3.49p at 1622 GMT.