A test shipment of containers filled with city refuse that was scheduled to be loaded and sent to the U.S. mainland tonight has been postponed, pending approval from the U.S. Department of Agriculture in Washington, D.C.

Hawaiian Waste Systems LLC president Michael Chutz announced this morning that the company could be loading a barge to leave tonight pending a decision from federal agricultural officials to allow them to ship the trash to the mainland.

 But Chutz said this afternoon that while the business received a favorable recommendation from agricultural inspectors today, the agricultural official in Washington, D.C. who would make the decision to lift the suspension had left for the day, so a decision won’t be made until at least Monday.

He said the next opportunity to send a test shipment will be in about three weeks.

The company plans to ship test containers with bales of city solid waste to the Roosevelt landfill in southwestern Washington. The project has been on hold for months as the company sought federal permission to ship the trash to the mainland.

Chutz said the U.S. Department of Agriculture is concerned about the potential importation of harmful alien pests from Hawaii in the shipments to Washington.

Chutz said the method of plastic bailing, scientifically tested and used worldwide, kills pests in the waste.