The Paris police headquarters began Monday (August 12th) to set up barriers defining the area around Notre-Dame where an ultra-high-pressure cleaning will take place on Tuesday to decontaminate the ground of the lead that penetrated it, according to the ministry. of the culture. The operation will begin with the Rue de la Cité, which will be closed to passers-by and traffic.
The method used, the ultra-high pressure, is made more efficient by the addition of a detergent, the surfactant, chemical agent for increasing the spreading and wetting capabilities of a liquid. This surfactant should be aspirated and recovered.
Work until August 23
A scrubbing gel will be applied in some places to allow the aspiration of the lead particles. The application of this layer should last a day. It will need to dry for three days and then be phased out, which should take at least five days. The ultra-high pressure solution, which will affect the main surfaces, should be faster than that of frost.
At the end of the operations, a control of their efficiency will be made. According to the police prefecture, the work, in several phases, will last until August 23. The RER station Rue de la Cité and Notre-Dame square will be closed and bus routes diverted.
Hundreds of tons of lead released
The fire, which partly destroyed the cathedral, melted and released on the one hand, and released in the form of particles on the other hand, the hundreds of tons of lead contained in the frame of the spire and the roof.
>> To read also: "Fire of Notre-Dame: 'No immediate instructions to avoid lead contamination'"
Suspended at the end of July, the Notre-Dame construction site should gradually resume on August 19th after the implementation of new drastic protection measures, especially for employees of companies working on the site.
With AFP