More than 4000 tonnes of recycled glass accumulated at the Central Otago WasteBusters site in Boundary Rd at Alexandra.
A 3000-tonne glass mountain was causing problems for the recycling centre, taking up space in the yard which is used to house and sort the entire district's collected recyclable material.
Another 1000 tonnes of sorted glass was also taking up room, and each week between 50 and 100 additional tonnes of glass was being taken in by the centre.
WasteBusters manager Karen Noble said glass had been stockpiled to prevent it from being dumped in landfills, with the hope it could become a useful commodity.
The glass mountain was continually being added to but in the process was rendered useless, she said.
"Whenever we pushed it up to make room for other glass, we actually contaminated it without knowing. Because of the sand and dirt, it could not be used in a glass crushing plant or sold," she said.
Instead, about 1700 tonnes of the contaminated glass was taken to a quarry near Lowburn.
Mrs Noble said new systems would be put in place at the centre to make sure all new glass was sorted and stored in a way to ensure it was not contaminated.
WasteBusters had been in touch with Auckland firm Owens-Illinois, which began buying sorted glass for $15 a tonne.
Mrs Noble said she hoped the company would increase its payment for the glass, although a small remuneration was still beneficial and it would free up space.
An Earnscleugh man's glass-crushing plant, which is expected to be installed at WasteBusters in May, would also put a dent in the stockpiled glass, she said.
Shining Path Ltd owner Mike Olsen said he was almost finished developing his glass crusher, which would be ready for installation and onsite trials soon.
