A LONDON-based law firm has written to Transport Secretary Chris Grayling identifying legal concerns over plans by Cromarty Firth Port Authority (CFPA) to transfer up to 8.4million tonnes of oil a year between ships in protected waters of the Cromarty Firth.

Four members of the pressure group Cromarty Rising instructed Bindmans LLP to help in their fight against the plans, which they fear will endanger the marine environment – in particular the breeding grounds for the bottlenose dolphin population. They asked Bindmans to review the evidence they have collated against the CFPA plans.

In a seven-page letter to Grayling, the lawyers set out their legal concerns, mainly relating to potential breaches of the Habitats Directives. They have also written to Douglas Russell, CFPA chair, inviting him to withdraw the application or face “a range of legal options including the possibility of judicial review”.

The port authority’s bid has attracted a range of objections from Whale and Dolphin Conservation, Scottish Wildlife Trust and the RSPB.

A spokesman for Cromarty Rising said: “This is not about nimbyism. Transfers of oil have been undertaken for years in the relatively safety of Nigg Jetty and we would have no objection to them continuing to take place there.

“This is about fighting the wrong development in the wrong place. The proposed anchorages are right in the middle of the bottlenose dolphin feeding and breeding grounds.

“We want to protect the waters around us for future generations and support sustainable development.

“This proposal threatens the viability of the dolphin population and many other aspects of the local environment. It is up to us to provide a voice for those who cannot argue for their place in the sea – the whales, dolphins and seabirds of the inner Moray Firth.”

More than 16,000 people have signed a petition against the transfers, and a crowdfunding page set up to help foot the potentially significant costs of a judicial review has raised over £2,000.

The spokesman added: “We sincerely hope that the CFPA will reconsider this application and work with its stakeholders for the sustainable development of the firth.

“If they choose not to, then we are digging in for a long fight and are prepared to throw the full weight of the law at them. We will work tirelessly until the application is either withdrawn or thrown out. We view the letter as an opportunity for the authority to withdraw gracefully and reset the clock on the relationship with the communities they serve.”

Apart from oil spill fears, campaigners are also worried that indiscriminate dumping of waste ballast water could have an equally disastrous effect on the eco-system.

Nobody from either the CFPA or the Maritime and Coastguard Agency was available for comment last night.