The huge Mountfield Park development in south Canterbury could be stalled after a High Court judge granted calls for a judicial review over pollution concerns.

Clean air campaigners put forward their case on Tuesday, claiming the Secretary of State should have called in the 4,000-home Corinthian Land application to investigate issues caused by extra traffic.

It was their second attempt to persuade the court to hold a review after their first “paper application” in February failed.

Campaigners Emily Shirley and Michael Rundell argue it has not been proven that the housing development will not worsen air pollution in Canterbury, which is already said to claim 100 lives a year.

Led by barrister Robert McCracken QC, they put the latest application in person to a judge, who agreed their case “was arguable”.

The judicial review is now expected to take place at the High Court in mid-to-late July.

If successful, the court could order the government to hold a planning inquiry, potentially stalling the application for months. Mrs Shirley said: “We are delighted, but our aim is simply to have an air quality plan in Canterbury that will actually show new development proposals will not actually make things worse, as is generally recognised with Mountfield Park.

"It will add 28,000 vehicle movements every day around and through Canterbury and it is unacceptable that the government turns a blind eye, especially after being told by the High Court to sort out air pollution nationally."

Recently, cyclist Martin Baker revealed how the filters in the breathing mask he uses to ride to work in Canterbury were turned black by vehicle exhaust emissions.

Mrs Shirley added: “If the city council and Corinthian say we don’t care and go ahead, the judge has also indicated to us that he would issue an injunction to put a stop on it.”

Although outline planning permission for the huge scheme has been granted by the city council’s planning committee, the formal decision notice has yet to be released because of the complicated conditions on developer contributions to the community.

But Corinthian Land has previously said it is "confident" the Secretary of State has not acted unlawfully by not calling in its application.

Boss John Trotter has warned that delaying the development could have "catastrophic" consequences for planning in the district, leaving the city council vulnerable to hostile applications because it had not fulfilled its commitment to identify enough land for housing quotas.

Mrs Shirley and Mr Rundell’s campaign group Switch (Sustainable Ways Integral to Canterbury’s Health) has launched a £25,000 appeal to fight the case and is leafleting the city in a bid to get financial support. They have already raised about £5,000.

City council spokesman Rob Davies says it is disappointing that the judicial review application has been allowed to proceed.

He said: “We fully support the Secretary of State’s decision not to call it in to ensure there are no delays in the implementation of this important development for the residents of Canterbury.

“"his will remain our position at any forthcoming hearing because Mountfield Park is crucial to the delivery of our Local Plan and our vision for providing the homes and jobs for people who want to live and work here.

"The planning application was subject to extensive public consultation and the decision was reached based on a detailed committee report and hours of thorough debate, including an air quality expert being in attendance.

"The decision to approve the Mountfield Park development was subject to the completion of a section 106 legal agreement. This formally specifies the infrastructure and contributions the developer must provide, including £25 million of road junction improvements for the A2, two new schools, a new park and ride site, a new health centre and significant open space.

"We are making good progress on finalising it and once that work is complete, the decision notice formally ratifying the December approval by councillors can be issued.

"Any involvement we now have in the judicial review process will mean spending taxpayers’ cash which we would far rather spend on services for residents.”