Six firms are preparing to submit final bids for a $500m deal to upgrade key gas distribution infrastructure in Abu Dhabi.

The engineering, procurement and construction (EPC) contract covers the installation of a new gas booster station, and the replacement of a natural gas pipeline at the Asab field in the south of the country for Abu Dhabi Gas Industries Company (Gasco).

Dodsal and the National Petroleum Construction Company (NPCC), both based in the UAE, South Korea’s SK Engineering and Construction, Athens-based Consolidated Contractors International Company (CCC), Milan-headquartered Techint, and Paris-based Technip all plan to submit prices for the deal on 6 October.

Gasco hopes the work will increase capacity at the site by 150 million cubic feet a day as part of the wider scheme at the Asab, Bab, Bu Hasa and Ruwais fields, called the ABBR project.

Twelve firms were prequalified to bid on the deal but contractors say the number of projects now being tendered in Abu Dhabi cut down the field of competitors significantly.

“We are going for a lot of tenders at the moment, and Gasco couldn’t push the deadline on bidding back for commercial bids so we decided not to go for it,” says a source at one of the companies prequalified for the bids round. “We asked for extensions, but they just couldn’t do it.”

Abu Dhabi will have awarded more than $30bn of engineering deals for oil and gas projects between the first quarter of 2009 and the first quarter of 2010, according to MEED research.