Abu Dhabi’s Zakum Development Company (Zadco) has delayed to 15 October the deadline for commercial submissions for an estimated $60m deal to upgrade its oily water treatment and disposal facilities at Zirku Island.

Bids were due to be submitted on 30 September, but Zadco informed bidders that it was pushing back the deadline by 15 days. The company did not give a reason for the delay, according to sources close to the scheme.

Zadco, a subsidiary of state energy firm Abu Dhabi National Oil Company (Adnoc), uses Zirku as its main base of operations. The island is located 140 kilometres northwest of Abu Dhabi.

Technical proposals were submitted on 23 August, with six international and local contractors prequalified to bid on the project.

The engineering, procurement and construction (EPC) contract for the first part of the deal was tendered by Zadco on 14 July, covering the construction of a new 12-inch pipeline to replace the existing transit route (MEED 12:8:10).

The company plans to tender the second part of the project in mid-2011. Details of this part of the scheme are not yet known.

The project is part of Zadco’s wider plans to upgrade the facilities and increase crude oil handling capacity to 750,000 barrels a day (b/d) from the current 550,000 b/d.