Singaporeans, Wan Jing Chao (34) and Sim Wei Der (50), and Malaysian Yap Loke Liang (36) are company directors of a used tire processing factory.
The three were accused of failing to conduct air quality monitoring and failing to notify the authorities about the waste disposal in the river.
They were also accused of abetting Malaysian lorry driver N Maridass (35) in dumping the waste into the river at the Sungai Kim Kim Bridge-widening project last March 7 between 12 and 1 in the morning.
Maridass has been charged in March under the Environmental Quality Act 1974 of Malaysia.
Wan and Sim will be charged in the Malaysian court on Dec 4.
If convicted, the directors face a maximum penalty of five years jail along with a RM500,000 (S$163,135) fine.
The polluted waters in Pasir Gudang have been classified as an oil sludge.
Read: 46 potential pollution sites identified in Pasir Gudang via satellite imageryFollow us on Social Media
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