Top start for the renaturation of an unauthorized landfill site

Site clean-up, a key step in healing the landscape

In Boissy l’Aillerie and Puiseux Pontoise, in the Val d’Oise, clean-up operations have begun. This is an essential step in moving on to the landscape restructuring phase. Disposal of the 14,000 m3 of waste began at the end of January 2022. This should take between 4 and 6 months. ECT covers the cost of disposal and treatment.

A look back at the creation of one of the largest unauthorized landfills in the Paris region

  • December 4, 2017: Start of illegal land occupation and intensive illegal dumping activities.
  • May 5, 2018: The Prefecture puts an end to the illegal landfill. The site entrance is secured by concrete blocks at the entrance to the farm road.
  • In 6 months: 6,000 tonnes / 14,000 m3 of waste were deposited on the site.

The unauthorized dumping of waste in the communes of Boissy-l’Aillerie and Puiseux-Pontoise has caused a great deal of damage. If no action is taken, this could lead to irreparable degradation of the site.

Municipalities helpless in the face of illegal dumping

Inert soil for an ambitious project

Extensive consultation was carried out with :

  • the private owner,
  • Agglomération de Cergy-Pontoise,
  • the municipalities of Boissy-l’Aillerie and Puiseux-Pontoise,
  • Val d’Oise department
  • decentralized government departments,

It was thus established that the site had sufficient available surface area to provide a suitable volume of inert soil. The objective? Create a high-quality agricultural and landscaping project. The reuse of inert soil provides ECT with financial capacity for the project. The challenge is precisely to balance the cost of waste disposal and treatment, and site renaturation, with the volume of soil received.

ECT has a number of tasks to carry out in order to rehabilitate the unauthorized landfill site:

  1. Support in taking account of urban planning and environmental constraints linked to the PLU. In consultation with the Val d’Oise Departmental Council and the French government.
  2. Financial and technical responsibility for waste removal and treatment.
  3. Quality redevelopment of the site through a development permit. Planning permission is granted by local authorities. It is accompanied by a request for environmental authorization (Water Law) examined by the French government.
  4. Waste disposal and treatment.

An ambitious project to restructure the landscape

  • The project calls for the restoration of agricultural areas and the recreation of a mosaic of natural environments (grassy, shrubby and wooded).
  • It takes into account the land, heritage and environmental constraints specific to the site and the NRP framework.
  • Given the current instability of the embankment, the project proposes to consolidate it by filling it in, while at the same time restoring suitable hydraulic management.

The former landfill site will give way to an agricultural, landscape and hydraulic renewal project within the framework of the Parc Naturel Régional du Vexin Français.

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