Surabaya. The Indonesian government has launched intensive monitoring of four companies operating along the Brantas River basin in East Java after uncovering suspected environmental violations during inspections last month.

The Ministry of Environment and Forestry dispatched an investigative team between August 20 and 23 to assess water quality in the Brantas and its tributaries. Findings indicated multiple breaches of environmental standards.

At Energi Agro Nusantara, investigators reported land expansion without updated environmental approval and direct discharge of waste -- including biofertilizer residue, production machinery runoff, and effluents from its water treatment plant -- into the Ngares and Jinontro rivers.

Molindo Raya Industrial was found to have constructed ethanol tank foundations and a new CO₂ plant, including 12 storage tanks and distillers dried grains with solubles (DDGS) facilities, without proper environmental clearance. The company also lacked technical permits for wastewater treatment.

Etanol Ceria Abadi, another company located near the Brantas, was found inactive and no longer producing wastewater.

Meanwhile, inspectors flagged two sugar plants operated by Sinergi Gula Nusantara. One facility lacked technical approvals for wastewater treatment in employee and mosque toilets and had not conducted mandatory ambient air quality sampling. Another plant stored boiler ash in scrubber water reservoirs instead of designated storage facilities, with technical details omitted from its environmental certification.

Government Warning
“The Brantas River basin is the lifeline for millions of people in East Java. Every company must operate in compliance with environmental documents and quality standards. The suspected violations will be pursued under applicable law,” said Rizal Irawan, Deputy for Environmental Law Enforcement.

Authorities have installed warning boards and monitoring lines at the four company sites.

“These measures -- such as sealing waste outlets, posting supervision signs, and installing PPLH monitoring lines -- serve as initial warnings. We will ensure that companies make tangible corrections and impose sanctions if violations persist,” added Ardyanto Nugroho, Director of Complaints and Supervision at the ministry.

The Brantas River, East Java’s largest, supplies water for agriculture, industry, and daily use to millions. The ministry stressed that strict compliance is crucial to prevent long-term ecological damage and safeguard public health.