Earlier this summer, police in Paris reported high levels of lead on the roads and gardens in front of the Notre Dame Cathedral which was devastated by fire on April 15th, 2019. Last month, cleanup work inside the cathedral itself was halted for safety reasons due to hundreds of tons of lead which melted in the fire. This week, Paris authorities have blocked off the surrounding area of the monument and erected high fences to keep people out. Decontamination is now planned by experts using two different techniques. The first method involves vacuuming the pavement, then scrubbing it, and finally a high pressure cleaning with a mix of water and chemical agents to both rinse the ground and recover the waste water. The second method will involve a lead-absorbing gel which will be put on public benches, street lights and other fixtures. After several days, the gel will dry and then be removed. The decontamination operation is expected to take about three weeks.