(CN) - British authorities may have admitted temporary defeat in their fight against London's air pollution, but that doesn't remove their obligations to submit specific plans on how to meet EU air-quality targets, the European Court of Justice ruled Wednesday.
The EU's air-quality directive required member states to meet air-quality targets limiting nitrogen dioxide by 2010. But the law also allowed European nations that knew they would miss those targets to apply for five-year extensions - provided they also submitted detailed plans for how they would achieve the air quality goals by 2015.
Authorities in Britain realized they would miss the target when in 2010, 40 of the 43 high-pollution zones registered nitrogen dioxide readings above EU limits. In 2011, the U.K. submitted postponement applications with pollution-abatement plans for 24 of the zones and projected compliance by the 2015 deadline.
But for the other 16 zones - including greater London - the British government admitted that pollution targets would not be met until as late as 2025, and did not request a time extension.
Environmental group ClientEarth took the U.K. to court seeking an order to require the British government to revise its plans to show how pollution limits would be met by the 2015 deadline in all zones, including the troubled London area.
The case eventually went to Britain's highest court, which asked the European Court of Justice whether EU law requires a postponement application when pollution targets cannot be met. The U.K. court also asked whether the halfhearted plan by British air-quality authorities - which ignored London and the other trouble areas - complied with the law.
On Wednesday, the Luxembourg-based court acknowledged that member states can request a five-year postponement in cases where - despite the implementation of pollution-abatement measures - acute air-quality problems persist. But the postponement is contingent on both having a plan to improve air quality and the presence of unrelenting pollution despite the measures, the court said.
But in the case of London and other high-pollution zones where the U.K. did not ask for a postponement, the court noted that EU law still requires an effective air-quality improvement plan with details on how to achieve nitrogen dioxide target levels in the shortest time possible.
"Moreover, that provision allows the deadline to be postponed only where the member state is able to demonstrate that it will be able to comply with the limit values within a further period of a maximum of five years," the court wrote. "That portion of the law has, therefore, only limited temporal scope."
The court tasked the U.K. judiciary with deciding whether Britain's air-quality plans meet EU requirements in this case and in future actions brought by environmental groups or concerned citizens.
The European Commission welcomed the high court's ruling, calling it a reminder for all EU states to remain vigilant in the fight against air pollution.
"The commission is now looking closely at today's ruling, which appears to confirm the duty of all EU member states to protect European citizens and deliver on air-quality standards within a reasonable time," the regulatory arm of the EU said in a statement. "It is now for the U.K. Supreme Court to apply the interpretation of the Air Quality Directive to the case before it."
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