Thomas McGlinchey, from Belfield Park, Derry, was found guilty in Derry Crown Court sitting in Coleraine on three counts of waste offending.
The 62-year-old was a director of Brickkiln Waste Ltd.
On October 14, 2013, officers from the Northern Ireland Environment Agency (NIEA) attended the lands off the Carmoney Road, Derry when they observed a lorry depositing controlled waste.
An intrusive survey under warrant revealed approximately 7600 tonnes of non-compliant waste.
This waste included items of household and commercial waste, food packaging, carpet, plaster board, construction and demolition waste and plastic trommel fines.
Brickkiln Waste Ltd was an authorised waste company at the time of the offence.
The receiving site on the Carmoney Road was not authorised or engineered to accept the waste streams identified during the Department surveys.
This type of waste should be treated in an authorised Materials Recycling Facility or disposed of at an appropriately authorised landfill.
The act of infilling the waste at this unauthorised area ultimately undercuts the legitimate waste industry, evades landfill tax and leads to environmental degradation.
The driver, John Ferguson (68), from Princess Terrace, Derry, was an employee of Brickkiln Waste Ltd and the company had leased the site for the purposes of depositing inert material.
John Ferguson was found not guilty on two waste offences regarding the deposit of this waste.
Sentencing of McGlinchey is due to take place on April 28, 2023, at Coleraine Crown Court.