AUTHOR of newly released novel ‘On The Swamp’, Jim Mynard, wants an investigation into the possible reasons for the Nar Nar Goon sink hole.
Noted community leader, Neil Lucas, officially launched the book at Edrington, Berwick, on Sunday 31 July.
Mr Mynard said the book focused very much on flooding concerns, but also discussed land subsidence.
He said the irony of the situation was a story about his book launch that appeared in the Gazette on 10 August with a story about the Nar Nar Goon sink hole in the same edition.
“The sink hole was spot on for timing,” he said.
He said the article described the sink hole as ‘mysterious’, but there was no mystery about it.
“Pumping in the Dalmore Cardinia areas was temporarily stopped in the 1960s and restriction placed on volumes when State Rivers and Water Supply officers said if it wasn’t controlled, land in the area could subside six feet within days.
“The official reason given later for imposing restrictions was ‘to protect against the incursion of sea water from Westernport Bay’.
“Geologists later expressed similar concerns for the Cora Lynn area.
“If there is a mystery about the Nar Nar Goon sink hole, in my mind it is why, in an area I am told, does not have extensive pumping?
“I believe there was high risk during the last drought of land cracking in the Dalmore Cardinia areas, but it didn’t happen, it happened at Nar Nar Goon in a wet season, several kilometres away.
“I have been concerned about the Kooweerup Pakenham Road for several years because of constant filling needed to offset subsidence along the road, and I was really worried about heavy machinery working on the Kooweerup Bypass, but all seems well.
“The Nar Nar Goon properties in the Seven Mile area are billiard table flat, except for a depressed area around the sink hole, which is of grave concern to me, and I imagine to the property owner.
“This sink hole needs to be investigated.
“I believe pumping from the concentrated agricultural area around Kooweerup, Dalmore, and Cardinia, taking into account the recent dry season creates a vacuum.
“This wet season has saturated the Seven Mile area and water finds the easiest pathway, which means it would have been making waterways to the depleted aquifer.
“Extra water at Nar Nar Goon in a wet season means a faster stream and soft swamp earth being washed away to create underground rivers with the unstable wetter-than-usual soil dropping until the roof caves in.
“A community committee needs to be created to build a map of subsoil clay pans because streams would probably flow around the clay.
“Clay also shrinks in groundwater irrigation areas to provide open areas for water movement.
“A study of the subsoil might help discover risk areas,” he said.
