Part of South Queensferry was still sealed off as the authorities attempted to resolve a leak of gas in dirty water from BP’s Hound Point Terminal.
The leak, from a pipeline serving the terminal, led to a 100-metre exclusion zone being set up and it was almost eight hours after the alarm was raised that health chiefs declared it did not pose a risk to the public.
Local residents said there was still a heavy smell of “rotten eggs” in the area late last night, however police said no-one had to be evacuated.
Lothian and Borders Police, which coordinated a multi-agency operation after a passerby spotted brightly-coloured water leaking into the Forth around 1:30pm, insisted the incident did not involve oil. However it is not yet known what other materials may have been in the “ballast water,” which was leaking from a tiny hole in a pipe connected to a nearby tank storage facility.
Police chiefs said the Scottish Environment Protection Agency (Sepa) was providing expert advice on any “possible implications of the leak.” Air quality tests were expected to be carried out at hourly intervals overnight, although the exclusion zone was scaled back at 11pm.
Inspector Dougie Stephens said: “The leak has been confined to a field but it has entered a burn which has discoloured the water. Liquid is still exiting the pipeline.”
Edinburgh Western MP Colin Keir said: “The priority now is for all agencies and BP to work together to put a stop to the leak as soon as possible and ensure there is no damage to the Forth. I will be in regular contact with Sepa and the police to ensure the public are kept fully informed of any developments.”
The terminal, which consists of two jetties, is the biggest North Sea oil export terminal in Scotland.
BP insisted the leak from a pipe connected to a tank farm at Dalmeny was of “stagnant sea water”, which is used to help oil tankers keep their balance before they are filled with cargo.
However, police sealed off an area from Standingstane Road, in Dalmeny, to the western end of South Queensferry High Street amid fears of a major chemical incident. As well as Sepa, the city council, the police and fire service were all involved.
One eyewitness, Lisa Dransfield, said: “I called Sepa as I live right next door to the where the leak happened. The discoloured water was bright yellowy-green and was more than trickling – it was gushing.”
A spokesman for NHS Lothian said: “Although this gas has a strong smell, it will have no impact on the health of local residents due to the low levels released. ”
A BP spokesman said: “The leak is of stagnant seawater that the tankers use as ballast to keep them stable. It is then discharged before oil cargo is loaded. It is not a chemical leak or an oil leak.”
Operations manager Tom Moore said: “People will not like it (the smell) and we understand it’s a nuisance but there are no ill affects in those concentrations and there will be no lasting impact.”