It is hoped the site will be clear by the end of the month, with the help of machinery breaking down material from the former Sealord factory in Birch St to be used as fill.
Council support services manager Gerard Collings said indications were 90% to 95% of the site's material could be recycled including concrete, steel, insulation panels and cool stores.
Not only was it providing substantial cost savings, it was standing the council in good stead for its Green Star building rating application, he said.
Objections to the council's notice of requirement for the building had been resolved and detailed design and costings were to be considered by the council in November.