The coal was carbonised using the Lurgi process, the result being coke and charcoal, with tar and creosote as by-products.

Waste from the plant was discharged directly into the nearby Awaroa stream, which caused heavy pollution of the waterway.

Following complaints about the pollution, Waikato Carbonisation Limited trialed a waste incineration programme, but the output of the plant exceeded the capacity of the burners.

The excess was pumped into waste pools up until the plant's closure in 1985, when major fire caused a retort to explode.

Following the private sale of NZ Steel, the land on which the plant was located passed onto the local regional administration.