SINGAPORE - Two men have been convicted and fined a total of $6,800 for illegally collecting greasy waste from grease traps.

The National Environment Agency (NEA) said on Thursday that the two men had mixed the greasy waste with cooking oil and then sold the mixture to companies that export used cooking oil for processing into biodiesel.

The first man was fined $3,800 for illegally collecting the greasy waste from traps serving a hawker centre at Bedok North Street 1 and eateries at Yishun Street 81 and Lorong 4 Toa Payoh. He did this four times between September and October last year.

The second man was fined $3,000 for taking the waste from traps serving eateries at Yishun Street 81 and Upper Aljunied Lane on three occasions between October and November last year.

The men could have been fined up to $2,000 for each offence. The NEA said it takes the proper collection and disposal of waste from grease traps seriously, and will act against any unauthorised waste collectors.

The cleaning of grease traps can be done only by licensed general waste collectors. They usually use vacuum trucks to collect the waste from the traps, and then dispose of it at national water agency PUB's designated water reclamation plant. The waste is digested with used water sludge to form biogas.

Anyone who has information on the unauthorised collection of the greasy waste can call NEA's 24-hour call centre on 1800-2255-632, or e-mail Contact_NEA@nea.gov.sg.

The NEA said people should provide details of the date, time and location of the incident, as well as any photos and videos that can provide leads for it to investigate.