Flames and smoke from the blaze at Five Turnings, between Clun and Knighton, could be seen for miles after it broke out on Monday night.
Together with the site owners the crews had to move gas cylinders to avoid explosions and create fire breaks to try to contain the flames.
There were also fears that embers shooting into the sky and landing on parched ground could cause a major wildfire.
Nearby residents were urged to keep doors and windows closed and some roads in the area had to be closed.
Investigations have begun into how the blaze started.
Shropshire Fire and Rescue Service group manager, Lee Baker, praised firefighters from across the county, fire control and crews from Mid Wales and Hereford and Worcester.
"They worked tirelessly to bring the fire under control," group manager Baker said.
"They ensured the fire did not spread to two houses and outbuildings nearby and followed special environmental procedures to protect local water courses and areas of special scientific interest from pollution."
The Environment Agency has been working with the fire service.
Adam Lines, environment manager for Shropshire, who was on duty on Monday, said a fantastic job had been done by crews and agency staff to minimise pollution.
"This could have been catastrophic for some of our most valuable local rivers such as Redlake Clun and Teme," he said.
Group manager Baker said he hoped that the firefighting operation could be scaled down overnight with a larger presence returning on Wednesday.
At its peak there were eight appliances and specialist units on scene as the fire spread through several hundred tonnes of scrap.