Cleanaway Waste Management (ASX:CWY) said the Victorian Supreme Court ruled in favor of the Environment Protection Authority (EPA) regarding an alleged historical underpayment of landfill levy at the Melbourne Regional Landfill for the fiscal year 2018, according to a Thursday Australian bourse filing.

The alleged landfill levy underpayment amount for the said fiscal year is AU$6.9 million.

The regulator brought the proceedings against Cleanaway in order to recover an alleged landfill levy underpayment on materials purchased by the firm from the adjacent Boral quarry for use in landfill operations.

Cleanaway's stance was that the type of product purchased from Boral should not be considered "waste" to which landfill levies should apply. It is reviewing the decision and has 42 days to decide whether to appeal the decision.

Its shares rose 1% in recent trading on Thursday.