Officials at Turquoise Hill Resources completed a detailed review of the tax ruling by Mongolian government regulators first issued September 10, reducing taxes, interest and penalties claimed payable by Oyu Tolgoi LLC, to $30 million from $127 million. 

The investigation included a repair of the rake and re-commissioning of the tailings thickener for the Oyu Tolgoi copper-gold mine. Turquoise Hill is in a Joint Venture with the Ulan Bataar government to run Oyu Tolgoi; deep in the Gobi Desert, it is expected to constitute 30% of GDP on completion.

Still, “there are aspects of the ruling that require further clarification to resolve outstanding issues,” added representatives of Turquoise Hill, a subsidiary of No. 2 miner Rio Tinto. The rake repair and re-commissioning of the tailings thickener are pending completion by September 30, company officials said in a statement.

The rate failure was linked to operational complications coupled with fabrication-quality problems; relevant controls and protections have been reviewed with changes for both thickeners. During repairs, noted officials, the concentrator continued running at 60% throughput.