Natural Resources Wales (NRW) is assessing the potential impact on the environment after a fire on Pentrebach Road, Pontypridd yesterday evening.
Officers from NRW were on site last night working with the South Wales Fire and Rescue (SWFR) during the fire which affected several businesses.
NRW staff have found evidence of oil in the River Taff following the blaze and are carrying out sampling work in the area. This is so they can find out the extent of the pollution and find out what can be done to reduce the impact on local wildlife.
The fire was extinguished this morning and SWFR have now left the affected area.
Officers from NRW will also be investigating the site to find out if anything can be done to reduce the risk of a similar incident in the future.
Dai Walters, Natural Resource Management Team Leader for NRW, said:
“Our rivers are incredibly important and part of our job is to protect them when incidents like this happen.
“Fires can affect the environment and local people which is why we respond to incidents as quickly as possible.
“Now that the fire is out we can start looking into what effects this has had on the local environment and the best way to tackle any pollution that’s been caused.”