Firefighters have been at the scene in Balby since 5.15pm yesterday, with 45 firefighters tackling the blaze at its height.
Although the size of the fire in Balby Carr Bank has been massively reduced, a spokesman for South Yorkshire Fire and Rescue said crews were expected to be there for the rest of today.
Three fire engines- plus supporting appliances – remain at the scene.
A spokesman said: “Our message to local people remains the same - please avoid the area and keep windows and doors closed.”
The fire involves mixed metals and industrial waste and covers an area around 100m by 40m in size.
A high volume pump is being set up to support the firefighting operation, with specialist waste fire advisors also in attendance.
An investigation into the the cause of the fire will begin once the fire has been fully extinguished.
A major fire in the same area broke out in April 2021 at Morris Metals in Balby Carr Bank, and firefighters were on the scene for several days then.