East Lothian Council and SEPA have claimed that further work will take place following a pollution incident in the River Esk in Musselburgh first reported on Friday.
Pictures surfaced across social media of the River Esk polluted by what appears to be oil running through its murky depths.
Local residents have expressed their concern for the water area, the surrounding wildlife and the pollution’s general impact on the environment.
Shona McIntosh, a local resident said: "Local people are very worried about the wildlife, and angry about how long it took before we saw any action.
"Even after finding the source of the pollutant - which took two days - the policy seemed to be to let all the fuel already spilled flow through the river system into the Firth.
"People are asking why more effort wasn’t made to absorb or pump out the fuel in the burn before it reached the Esk, which might have reduced the terrible impact on our birds, mammals and fish."
The council has said they appreciate the community’s concerns and further booms and inspections will be implemented on the river to contain material, and further protect the environment.
Together with its contractor and SEPA, the council has said it is continuing to assess remediation measures.
An East Lothian Council spokesperson said: “SEPA officers have been on site monitoring the impact and continuing investigations into the cause.
"Close monitoring of wildlife on the river continues, with any distressed birds being taken into care by the Scottish SPCA as space at their National Wildlife Rescue Centre becomes available.
"Given the current national risk of avian influenza (bird flu), it is requested that the public do not touch or handle any birds but instead report these to the Scottish SPCA on 03000 999 999.”
According to the council, SEPA is unable to comment further at this stage “given the matter is a live investigation and due to the potential for enforcement or criminal action.”
SEPA has asked for anyone with information to contact its 24 Hour Pollution Hotline on 0800 80 7060, via sepa.org.uk/report or to contact CrimeStoppers anonymously on 0800 555 111.