According to the Fair Work Ombudsman, the low wage rate resulted in the couple being short-changed more than $86,000.
The Agency announced today that it was taking legal action in the Federal Circuit Court against Delahill Pty Ltd, which trades as ABCO Plastics at Guildford.
Also facing Court is company director and part-owner Guilherme Roque Rebello.
Delahill and Rebello allegedly breached workplace law by failing to comply with a demand to back-pay the two casual factory workers a total of $86,695.
The employees - a husband-and-wife from Sri Lanka, aged in their 50s - were in Australia on bridging visas and spoke limited English.
The husband was allegedly underpaid $10,197 between July, 2009 and June, 2010.
His wife was allegedly underpaid $76,498 between January, 2010 and September, 2014.
The underpayments are the result of the employees allegedly being paid flat hourly rates starting at $8 for a probation period and later increasing to $13 to $14.
The couple was entitled to normal rates of more than $17 an hour and up to $32 an hour for overtime.
Fair Work inspectors investigated after receiving a request for assistance from the couple.
In April, the Fair Work Ombudsman issued a Compliance Notice requiring Delahill and Rebello to rectify the underpayment within 28 days – but they did not comply.
Under the Fair Work Act, business operators must adhere to Compliance Notices issued by Fair Work inspectors or make a court application for a review if they are seeking to challenge a Notice.
Fair Work Ombudsman Natalie James says the Agency made extensive efforts to resolve the matter voluntarily outside of Court, but was unable to secure sufficient co-operation.
Delahill faces a maximum penalty of $25,500 and Mr Rebello faces a maximum penalty of $5100. The Fair Work Ombudsman is also seeking a Court Order for Delahill to back-pay the employees in full.
James says the Fair Work Ombudsman will not tolerate employers failing to promptly back-pay workers who have been underpaid.
"We prefer to assist employers to rectify inadvertent non-compliance issues but we are prepared to take legal action against employers who refuse to co-operate," she said.
Employers and employees seeking assistance can visit www.fairwork.gov.au or contact the Fair Work Infoline on 13 13 94. An interpreter service is available on 13 14 50.
