FEARS are mounting that toxic contaminants may have leached from the polluted Ravenscraig social housing building site after dirty floodwater spewed out onto a busy Greenock road.

The escape from the sprawling 83-acre estate — which has confirmed 'multiple exceedances' of potentially harmful chemicals — lasted for more than nine hours, according to eyewitnesses.

Developers of the poisoned land insist that the health and safety position on contamination 'has not changed' as a result — but did not explain how they had arrived at this conclusion.

Meanwhile, Inverclyde Council — despite setting a planning condition that 'all surface water originating within the site shall be intercepted within the site' — says it has no remit to act.

The local authority says it is a matter for the Scottish Environment Protection Agency (SEPA).

However, SEPA — in response to a concerned member of the public — said: "Please be advised that the relevant authority on planning permission and contaminated land issues is the local authority.

"Therefore, please forward your concerns to Inverclyde Council."

The council today maintained it has no jurisdiction in the matter, despite that instruction.

A Municipal Buildings spokesman said: "Any water coming from the site is a matter for the developers.

"The regulatory body in this instance is SEPA."

Local residents say the flooding started at around 9am on February 5 and continued until early evening that day.

Householder Alan Cumming has accused the council of a 'dereliction of responsibility'.

Mr Cumming said: "The fact this slurry was allowed to pollute a main road for over nine hours is not only negligent but a danger to public health.

"Inverclyde Council, who have retained control of the site, has said we should contact the developer over issues of concern.

"This dereliction of their responsibility further exposes the danger we face.

"An MSP demanded construction should halt, and so it should."

The council refused to be drawn on the fact that it is responsible for the Neil Street railway bridge which bore the brunt of the flooding.

Photographs of the flooding reveal large pools of discoloured water forming in public areas on Inverkip Road — and a video shows a woman pedestrian unable to negotiate the obstacle.

The Telegraph asked developer Link Group Ltd if it could guarantee the water was not contaminated with particles from confirmed pollutants, which include cadmium, mercury, arsenic and lead.

A spokesman for the company and social housing provider said: "Excessive rainfall has resulted in water emanating from the development site at Ravenscraig, the position on health and safety with regards to contamination has not changed due to this.

"The relevant authorities are satisfied all work continues to be delivered in accordance with the agreed remediation strategy."

Link previously admitted that 'assurances' it gave to the Scottish Government that contaminants were 'not leachable or soluble and will not migrate horizontally' were incorrect.

The concession came after respected contamination expert Professor Andrew Watterson told the Telegraph that 'under various conditions and exposure to various environmental factors, some of the heavy metals found on the site would be leachable' and in some circumstances 'would be soluble and capable of migration'.

With reference to the council's planning condition that all surface water must be 'intercepted within the site', the professor said: "With exceptional rainfall now being the norm, it would be interesting to know how they can guarantee this."

Link Group Ltd — which stands to received £15.3m of public money for developing Ravenscraig — acquired the polluted site in a so-called 'back-to-back' £1 deal involving the Scottish Government and NHS GGC in 2017.

MSP Stuart McMillan last year declared he'd 'lost confidence' in the 198-home development and called for it to be halted while the police probe remains live.

The Scottish Government says the land transfer was conducted 'in accordance with all due process'.