INTERVIEW-Hydro unsure when to resume operations at No.1 alumina refiner

BARCARENA, Brazil, March 5 (Reuters) - Norwegian company Norsk Hydro ASA is unsure about when it would be able to resume full operations at the world's largest alumina refiner, Alunorte in Brazil, company Chief Executive Richard Brandtzaeg told Reuters on Monday.

Alunorte, located in the northern Brazilian state of Pará, declared force majeure on Friday after local authorities ordered it to halve its production over fear of water contamination.

Brandtzaeg said the company was working on a complete evaluation of the situation at Alunorte, with the help of independent consultants, and that only after the analysis is finished will it be able to estimate when operations could go back to normal.

"We have launched an independent review and will make any final conclusion when we have the full picture," he told Reuters by phone after visiting the site in the municipality of Barcarena, which can be reached by road traveling around 100 km (60 miles) from Pará's capital, Belém.

Norsk Hydro took other steps on Monday to deal with the situation in Brazil, including naming current Chief Financial Officer Eivind Kallevik as interim head of bauxite and alumina.

It also announced a plan to improve water treatment at the plant.

But the company still disputes the accusations from Brazilian authorities regarding the contamination of water supplies in the Barcarena region.

"We have no indication that we have caused contamination or harm to the environment in Barcarena. Still, our main concern now is to help people with water and health treatment," Hydro's CEO said.

A federal institute linked to Brazil's Health Ministry said earlier that it has indications of overflow of Alunorte's effluents, causing high levels of aluminum in the water.

Brazil is still recovering from its largest ever environmental disaster in 2015 when the collapse of a tailings dam at the Samarco mine killed 19 people. Mud from the dam destroyed a village and polluted the river Doce in two states. (Writing by Marcelo Teixeira; Editing by Jonathan Oatis)