Cash that was dirty and appeared to have been buried, and money kept in plastic bags, was used in large transactions at the SkyCity Adelaide (SCA) casino, according to court documents.
The allegations are contained in documents submitted to the Federal Court as part of civil proceedings against the casino operator by Australia's financial crimes watchdog.
The Australian Transaction Reports and Analysis Centre (AUSTRAC) has launched the action for alleged serious and systemic non-compliance with Australia's anti-money laundering and counterterrorism financing laws.
The watchdog began investigating the casino last year as part of an industry-wide compliance program.
The court documents state SkyCity "failed to carry out due diligence on 124 customers", a breach of laws that could result in fines of more than $2 billion.
The documents state that the casino recorded $4 billion in combined turnover from those customers from December 2016, with about $74 million in losses by the customers.
"SCA was aware that some of the customers had been charged or arrested in connection with offences, including dealing with the proceeds of crime and money laundering," the AUSTRAC documents state.
"And SCA was aware of information suggesting that some customers were connected to organised crime or that their source of funds or source of wealth may otherwise not be legitimate."
AUSTRAC's statement of claim outlines the cases of 59 customers, including one person whose occupation at one point was listed as "meatpacker".
The person known as "customer 29", who recorded a turnover at the casino of more than $85 million in a four-year period, told casino staff they had recently sold their business and house.
But AUSTRAC alleges one of the customer's parents and two siblings had been convicted for the sale and supply of heroin in 2009.
The documents said those three family members had also been members of SkyCity Adelaide.
SkyCity banned the customer in March 2021.
'Soiled with a strong aroma of dirt'
The documents also contain details about "customer 30", who allegedly told the casino they worked as a chef at a small restaurant, their primary source of funds.
That customer turned over more than $34 million in four years.
"Customer 30's family network included individuals that had been convicted of drug dealing," the court documents allege.
"On several occasions Customer 30's known associates had presented cash that was soiled with a strong aroma of dirt.
"Customer 30 then received chips from these associates after the cash exchange."
The customer was banned from the casino in August 2021.
The documents also outline customers with links to organised crime, some of whom were suspected of loan sharking activities, and another who was believed to have connections to human trafficking and sex slavery.
Another had been detained by a foreign government over corruption and money laundering charges.
Many of the customers were taking part in "junkets" where someone from outside the casino, brings a group of people to the venue.
In a statement to the ASX, SkyCity said it had been informed of AUSTRAC's court proceedings and "will give the allegations … careful consideration before responding".
AUSTRAC has launched a similar prosecution against Star Entertainment, which owns casinos in New South Wales and Queensland.
