The Batam Customs and Excise Office has warned the importers of 49 containers filled with hazardous waste to follow the government’s order of returning the waste to their countries of origin within 90 days.

Office head Susila Brata said the he had sent letters ordering four companies which were responsible for the delivery of the illegal containers—most of which were from the United States—to return them following a recommendation from the Environment and Forestry Ministry.

The containers, which were described as containing plastic scraps for industries on their manifests, turned out to contain diapers and toxic waste, which are illegal to import.

Susila said that according to good importation procedures, the importers had 90 days to begin the return process from their arrival on June 13. This means that the companies have to send the containers back to US, Australia, Germany, France and other European countries by the middle of September.

“If they don’t comply, their import licenses will be revoked and the Trade Ministry and the environment ministry will investigate them,” he said.

The customs and excise office seized 65 containers at Batu Ampar Port following reports that they contained toxic and hazardous waste. An inspection by the environment ministry and local authorities found that only 16 containers met import standards.

The illegal containers are registered to PT Royal Citra Bersama, PT Wiraraja Plastic, PT Tanindo and PT Cakra Abadi.

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Previously, Royal Citra Bersama director Amin said he was surprised by the seizure and inspection at the port because the delivery of plastic scraps was routine for local industries that produced pellets for China.

“The imported waste is from the US and has been surveyed there to meet the standards for pellet production. We have had no problems so far, I wonder why there is an issue now,” he said. He has run a plastic waste processing plant since 2000.

Amin could not be reached for comment after the environment ministry ordered the return of the containers.