THE owner of the Grantham sand plant which some residents argue worsened the 2011 flood has accepted part of one of the quarry's walls could have been human-made.
After looking at aerial photos from before the flood which killed 12 people, Denis Wagner agreed part of a bund wall appeared to have been built up.
But he told the inquiry into the Lockyer Valley disaster that he could not recall seeing a western or eastern bund before Wagners purchased the quarry in 1998.
Mr Wagner said if he ever saw the bund, he would have assumed it was built for safety purposes.
He maintained quarry workers did not build up the wall because it was near a powerline and the company had strict guidelines about working around powerlines.
Mr Wagner did concede workers might have dumped overburden material there, without his knowledge, out of convenience.
But he remained sceptical that had occurred because company policy was that material be dumped on the southern side of the pit.
In any case, he did not consider the wall would have formed a levee bank because the lowest area where water was likely to enter the quarry was not filled in.
As part of the inquiry, Commissioner Walter Sofronoff must consider whether the existence of the quarry caused or contributed to the flood.
Several current and former employees of Wagners will give evidence to the hearing, which is in its second week.
The inquiry has received a hydrology report the Wagners commissioned that states the quarry did not cause or contribute to the flood.
A report is to be delivered to Premier Annastacia Palaszczuk by August 31.
- APN NEWSDESK
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