Restart of Notre-Dame restoration pushed back to August 19

View of the Notre-Dame Cathedral towers from the forecourt in Paris. EPA

Pressure rises on French authorities after an NGO files a lawsuit accusing them of failing to quickly contain the risks of lead poisoning after the fire that ravaged Notre-Dame cathedral in Paris last April. AFP

This file photo taken on July 17, 2019 shows damage on the nave and rubble during preliminary work in the Notre-Dame de Paris Cathedral three months after a major fire in Paris. AFP

The service entrance of the construction site of the Notre-Dame Cathedral in Paris. The yard has been stopped since analyzes proving an excessive presence of lead and the risks taken by the workers three months after the Cathedral was badly damaged by a huge fire last April. EPA

A worker sprays an anti lead decontamination treatment at the St Benoit Elementary School in Paris, France. EPA

Workers have started decontaminating some Paris schools tested with unsafe levels of lead following the blaze at the Notre Dame Cathedral, as part of efforts to protect children from risks of lead poisoning. AP photo

Worker directs a mechanical shovel grabbing pieces of destroyed surfacing to gather up the lead particles in the school yard of Saint Benoit primary school in Paris, France. AP photo

A worker holds a canvas bag as he takes part in a clean-up operation at Saint Benoit school near Notre-Dame cathedral in Paris during a decontamination operation over lead poisoning fears. AFP

A worker sprays a gel on the ground to absorb lead as he takes part in a clean-up operation at Saint Benoit school near Notre-Dame Cathedral in Paris during a decontamination operation. AFP

Paris officials moved to downplay the risk of lead poisoning from the massive fire that tore through Notre-Dame Cathedral in April, as tests continue to show worrying levels of the toxic metal at nearby schools. AFP

A worker stands next to asphalt waste materials as he takes part in a clean-up operation at Saint Benoit school. AFP

This picture taken on August 6, 2019 shows asphalt waste materials during a clean-up operation over lead poisoning fears at Saint Benoit school. AFP

An excavator removes the ground of Saint Benoit elementary school on August 8, 2019 during a clean-up operation over lead poisoning fears. AFP

Renovation work at Notre-Dame Cathedral in Paris could resume on August 19, a government official said Friday, after the clean-up was halted last month over fears that workers could be exposed to lead poisoning.

Testing revealed dangerously high levels of lead contamination at the site as well as at nearby schools and other buildings, prompting fears that workers and residents risked exposure to the toxic metal.

Hundreds of tonnes of lead in the roof and steeple melted during the April 15 blaze that nearly destroyed the gothic masterpiece, with winds spreading the particles well beyond the church's grounds.

But after weeks of denying any poisoning risks, authorities admitted in late July that anti-contamination measures were insufficient, and two schools near the church were closed after hazardous lead levels were detected.

Since then officials have been racing to implement tougher safety measures for workers at the site, while deploying new methods to remove lead residue from school playgrounds.

Prefect Michel Cadot, the government's top official for the Paris region, will allow work to resume "once there is a guarantee the new measures are in place," his office said in a statement.

Officials had originally said the clean-up could begin next week, but the target date is now set for August 19, it said.

New techniques

This week workers dressed head-to-toe in white hazmat suits sprayed a blue-green gel onto the playground at the two closed schools on the Rue Saint-Benoit, where dozens of children had been attending summer day care programmes.

According to city officials, the gel attracted and trapped the lead particles on the ground as it dried, and was later removed with high-pressure hoses.

That procedure and others will also be used on the square in front of Notre-Dame and on streets in the immediately vicinity.

Readings of more than 70 microgrammes per square meter indicate potential health hazards, but testing has found much higher levels at buildings as far as one kilometre from Notre-Dame.

Last week, the city revealed that some schools and day cares beyond a 500-metre perimeter of the church still showed isolated readings of more than 1,000 microgrammes on playgrounds or windowsills.

Critics have accused the city of failing to notify the public about the worrying results, while an environmental group has filed a lawsuit alleging that officials failed to sufficiently contain the contamination.

Others have urged authorities to cover the entire church with protective cladding to contain the particles, a system often used when removing asbestos.

City officials have rejected the proposal as too costly and complex.

But they have vowed that no schools will reopen in September unless the lead risk has been completely eradicated.