The Saudi Arabian Mining Company (Maaden) plans to build a 450-kilometre, 20-inch pipeline to take treated sewage effluent from Taif to its gold mines in north-west Saudi Arabia.

“We have decided to take the treated water because it is suitable,” said Hany al-Dabbagh, Maaden’s vice-president of precious metals and exploration at the MEED Saudi Arabian EPC Projects 2011 conference. “The reason to choose Taif rather than Riyadh as the source of water is the altitude. From Taif, we have gravity helping us.”

Al-Dabbagh said that tests showed there were no suitable sources of groundwater in the gold mine region. Maaden also considered the possibility of gathering rock containing gold in a central processing plant close to existing water sources. This approach was rejected as impractical.

Maaden has appointed a project management contractor for the pipeline and the EPC contract for the construction of the pipeline is scheduled to be awarded by the end of 2011. The pipeline is due to be completed in time for the start of production at Maaden’s four new gold mines.

Al-Dabbagh said Maaden reached an agreement with the National Water Company (NWC) about a connection with its sewage treatment plant in Taif, which produces 45,000 cubic metres of water a day. “We started our negotiation to take 10,000 cubic metres a day, which is about 25 per cent of the plant’s capacity,” Al-Dabbagh said. “And they have accepted that on the condition they will double their capacity to 90,000 cubic metres a day.

The Maaden water pipeline is the most ambitious new way of using treated sewage effluent, which is now being supplied commercially by the NWC.