Public submissions on the Environmental Impact Statement closed a few weeks ago, and several locals took the opportunity to share their concerns with me.

I have stated publicly that I wanted the remediation to be world’s best practice.

Some locals have been concerned that the plan to bury spent pot linings and other waste in a containment cell in the ground is not world’s best practice. Some said they preferred the material be recycled; others said they didn’t care what happened as long as it was not buried on the site.

I sought a meeting with Hydro representatives last week, to share these concerns, and hear fully about their plans for the site.

First, they assured me what they were proposing is world’s best practice. 

Second, they point out that it will have to be approved by the regulator, the Department of Environment and Planning, so the decision to go ahead with a containment cell will not be theirs alone.

Third, they do plan to recycle some material, but maintain not all of it can be recycled.

The waste that was piled up as “Mount Alcan” between 1969 and 1993 contains materials that, according to Hydro, cannot be recycled, including asbestos. This material is to be dug up and moved by truck to a new purpose built cell about a kilometre away on the western side of the smelter buildings.

Spent pot-liner was stored in sheds from 1993 onwards, and the goal is to re-use or recycle this material.

The greatest environmental concern from spent pot linings comes from high concentrations of cyanides and fluoride that are readily leached. There are concerns these might leach through the lining of the containment cell. Hydro says, in the unlikely event that could happen, there is a contingency built in to trap and manage leachate.

I raised with Hydro a process I had been told about called plasma-arc solidification, which would treat the waste under very high temperatures to a point where it could be more safely buried.  Hydro said this process was not yet proven, not ideal in the circumstances, and therefore not considered the best option.

While Hydro representatives have assured me they are using best practice and state regulators will have the final say, I, along with many others in the community, will be watching vigilantly.