Emergency services were called to Oswestry Waste Paper on the Mile Oak Industrial Estate at around 9.30am after reports came in of a leak of a hazardous substance.
Shropshire Fire & Rescue service said four appliances, including the Environmental Protection Unit, were sent from Ellesmere, Oswestry and Tweedale. Operations and Hazmat officers were in attendance.
Attending crews used breathing apparatus and decontamination equipment to deal with the spill, with one appliance still on the scene at 12.30pm.
The fire service said: "This incident involved a substance which has leaked onto the yard. Crews made the area safe and safely contained the substance."
The spillage comes less than 24 hours after a lorry spilt ferric chloride on the Mile End roundabout, leading to long delays on the A5.
Ferric chloride solution is used to treat sewage and industrial waste, to purify water, as an etching agent for engraving circuit boards, and in making other chemicals.