Hunt for clay delays landfill rehab
DIFFICULTIES finding suitable clay are holding up second stage rehabilitation works at old landfill sites at the Porepunkah tip.
Clay used as a landfill liner has to meet Environment Protection Authority (EPA) requirements.
“We work with the EPA who essentially define a range of requirements that we have to put in place to cap the landfill cells,” Alpine Shire Council director assets Will Jeremy said.
“We’ve got to meet certain standards with the clay that’s impermeable to water so we can’t get water leaking through.”
“We’re struggling to find suitable clay in the local area so it’s slowed down the completion of the works.”
The first stage of rehabilitation works at Porepunkah were done several years ago with clay that was found immediately ad- jacent to the landfill site, located off Roberts Creek Road, used.
But Mr Jeremy said commencement of stage two works were dependent on sourcing more clay.
“We’ve done quite a bit of work to find clay locally and will soon go out to see if anyone has clay that we can use,” he said.
“The cells we are rehabilitating, the thickness of the clay that goes on top needs to be about 700mm which has to be shaped properly and pass testing by the EPA.
“If we can’t find clay of a suitable quality that’s close by we’ll have to look at redesigning.
“There are also other things we can do that reduce the amount of clay, we can put geo-fabric in but essentially a redesign is quite a complicated process.
“Because the design has to go through an independent auditor before being certified by the EPA it would be quite a long and involved process to get a new design done.
“We’ll try and exhaust all possibilities to secure suitable clay for the site before we have to go down that path.”
Running parallel will be rehabilitation works at Myrtleford where Mr Jeremy said good clay had been identified.
Designs for Myrtleford have been done and are currently being reviewed by auditors.
“The auditors have come back with some comments they want us to incorporate in the design but essentially once that’s agreed upon and is sent to the EPA to be rubber stamped it will be ready to deliver,” Mr Jeremy said.
It’s hoped the design will be signed off this financial year with rehabilitation works at Myrtleford estimated to cost $500,000 while stage two works at Porepunkah are coming in at $800,000.
“These are big civil projects,” Mr Jeremy said.