Air pollution: it's not good to breathe at the foot of Mont Blanc

In Chamonix, they are proudly called "mules". These electric mini-buses crisscross the streets of the small alpine resort of nearly 10,000 inhabitants. They are part of the measures put in place for six years to try to reduce the use of polluting transport whose emissions literally choke more than 160,000 people in the Arve Valley that connects Chamonix to Contamine-sur-Arve (Haute-Savoie ). Las! it is still not good to live at the foot of Mont Blanc, where the atmosphere exceeds safety standards more than 35 days a year. Like Paris, Lyon or Marseille, this tourist region fails to meet the requirements of European directives. Worse: according to the epidemiological survey published in September 2017 by Public Health of France, exposure to air pollution in the 41 municipalities concerned is the direct cause of 8% of mortality in the valley, or 85 deaths per year . The longevity of an inhabitant now 30 years old will be – if nothing is done – amputated by nine months because of this permanent inhalation of fine particles and oxides of nitrogen. In total, the inhabitants of Arve today lose nearly 1,800 years of existence. "This study appears more alarming than we thought" is outraged Anne Lassman-Trappier, president of the local association Inspire 74 who now places all his hopes in a new Plan of protection of the atmosphere (PPA), more draconian that should be made public in mid-2018.

These poor results sign the failure of the first PPA developed in 2012 to try to fight against pollution peaks. In particular: the intense road traffic, with more than 600,000 trucks leaving each year to attack the Mont Blanc tunnel and responsible for 70% of nitrogen oxide emissions. And wood burning in 18,000 open fireplaces, responsible for 57% of fine particle emissions in winter. Conditions aggravated by the geographical situation of the valley which undergoes during a period of anticyclonic episodes a phenomenon of "thermal inversion"

While the upper layers of the atmosphere are warmed by the sun, the lowest ones remain at a lower temperature, blocking the polluting emissions on the ground. "Not only is the Arve Valley concealed, but also the thermal inversion layer is 50 meters above the ground when it is 300 meters above a city like Paris " , says Jean-Luc Jaffrezo, deputy director of the Institute of Environmental Geosciences (IGE, Grenoble).

But despite the health emergency, "the first PPA was made in a certain general skepticism "remembers Alain Nahmias, president of the Association for the respect of the Mont-Blanc site (ARSMB). "The industrialists, the motor carriers and the elected officials sent the ball back to them, and the public doubted that its heating practices and the use of the personal car could be responsible for the situation." [19659002] Thus, despite incentives in the form of subsidies of up to 2,000 euros, only 2,200 households have opted for a powerful insert against the 3200 expected … And the inhabitants of the valley are quick to incriminate second homes. "It's cultural, people think that the mountain in winter is the fire!" regrets Alain Nahmias. As for heavy goods vehicle traffic, it has progressed to 5,000 trucks a day since the recent economic recovery and, due to a lack of budget, the four communities of communes in the valley have not been able to set up an adequate bus line. 19659002] On the industrial side, the commune of Passy, ​​the black spot of the Arve, does not know how it can regulate the emissions of the household garbage incinerator on its territory, nor those of a factory which – paradoxically – manufactures carbon parts for car batteries … electric! These manufacturers argue, certainly, that they comply with emission standards … but their contributions (12 tons per year for the carbon plant) worsen the situation.