Lawmakers remain wary of a controversial pair of proposed bauxite mines being built in the Central Highlands.

During a weekend inspection of the construction sites, Nghiem Vu Khai, vice chairman of the National Assembly’s Committee for Science, Technology and Environment, demanded that the “red mud” reservoirs – holding pens for the alkaline sludge generated while refining bauxite into alumina – must be positively foolproof.

Khai told representatives of Vinacomin (Vietnam’s nationalized mining body) that he was concerned about the possibility that flooding or earthquakes would cause toxic spills.

The two facilities, Tan Rai and Nhan Co, are under construction in two adjacent provinces of Lam Dong and Dak Nong respectively. The Tan Rai plant is expected to go online next year and yield 650,000 tons of alumina.

The projects garnered widespread opposition, even before they got underway. Further fuel was added to the fire when disaster struck at an iron ore mine in Cao Bang Province, on November 5.

A breach in a slurry reservoir caused a wave of untreated waste to spill into the Duyet Trung Commune, spoiling the farmlands of 50 households.

During the two-day inspection of the proposed mine sites, Duong Van Hoa, Vinacomin’s deputy general director, told the legislative delegation that the company has reviewed the project and is preparing to amend their plans.

“We are willing [to invest more],” he said. “A supplemental investment of VND2 billion (US$102,616) is nothing compared to the project’s investment of more than VND2 trillion.”

In addressing concerns over the extensive foreign control over the project, Hoa announced that the primary Chinese contractors have agreed to hire more Vietnamese sub-contractors.

At the end of the inspection, Dang Vu Minh, chairman of the parliamentary Committee for Science, Technology and Environment, called for continued debate and scrutiny over the safety of the mines as they continue to be built and become operational.