A construction union member who instigated an internal corruption investigation says his claims weren’t properly investigated and made him the target of bullying.
CFMEU member Andrew Quirk told the union's National Secretary Michael O'Connor of his concerns of corruption in December last year, prompting an internal investigation.
His allegations related to George Alex, an underworld figure with ties to labour and construction companies, and resulted in him being "treated like an outcast" in the union.
"This is all taking place against a backdrop of going to work every day and dealing with people at your workplace who are pretty experienced thugs who are plainly sizing you up to see which leg they want to break first," Mr Quirk told ABC's 7.30 program.
Mr Quirk claims Mr Alex owed hundreds of thousands of dollars in union member benefits and was at least eight months behind in payments.
He says he found additional evidence to support his corruption claims but got the impression Mr O'Connor was not interested.
The internal investigation found no evidence of corruption.
During the royal commission into union corruption, it was alleged Mr Alex paid CFMEU NSW branch officials to keep them in his pocket.
The internal investigation was labelled a whitewash during the royal commission - an allegation the CFMEU denies.
The CFMEU also denies any corrupt relationship between the union and Mr Alex.
"Neither the union investigation, nor the royal commission with all its coercive powers and its authority to access telephone interceptions, has produced any credible evidence to substantiate that claim," the union said in a statement on Thursday.
"All parties involved have had the opportunity to put their case and considerable resources have been committed to investigating them."
The CFMEU says it's clear there is a faction within the NSW branch that is trying to "destabilise the current leadership".