(Quebec) Quebec City hopes to clean up a vacant lot near the incinerator in Limoilou, by growing trees and plants.
This pilot phytoremediation project – a first for the City – was initiated in December. The Environment Service wants to associate with a research center and a university in the coming months to complete it. Once the preparatory studies will be conducted in the spring planting will begin.
“This is a process that is promising, but is long. It may take ten years, because you have to let nature do what she has to do, “says Emilia Bruneau, spokesman for the City of Quebec.
The principle is simple: instead of excavated earth polluted with metals or hydrocarbons and replace it with clean soil, the land is left in place and the trees are planted there, shrubs or grasses, which will be extract soil contaminants or cause to degrade. The type of vegetation that will be planted on the ground at the corner of the road to Canardière and Montmorency Boulevard depend on the technique that will be chosen.
If the plants have a mission to remove contaminants, they will be planted two to three years, the time to capture the maximum possible pollutants before being cut and probably incinerated. “We would not send these plants then in compost, for example,” says Ms. Bruneau.
This technique would eventually save millions of dollars and give new life to the land left behind. In a decision summary dated December 4, the City believes that decontamination of the land in the traditional way would cost $ 4 million. Phytoremediation in turn would cost $ 200,000 initially and $ 100,000 annually for 10 years, for a grand total of $ 1.2 million.
This land of 12,000 square meters was sold to the City at this autumn by the company AIM Québec, which recycles metals. He was selected for this pilot project because it also is part of a larger project, the greening of the industry, identified as an island of warmth and unloved citizens.
“People living near the incinerator would not necessarily like to see it, so we want to put a bit of nature in this area, to improve their quality of life,” says Ms. Bruneau. There will be plants and trees on site over the next 10 years, but the land will remain a research area, not accessible to citizens. “As long as it is polluted, people should not expect a public park with benches and trails,” says Ms. Bruneau.
Phytoremediation is an emerging technique in Quebec interested more municipalities and governments. Conventional decontamination technique has the advantage of being fast but it only postpones the problem, the land is not cleared; only buried elsewhere.
In November, the City of Montreal has an agreement of $ 780,000 with the Plant Biology Research Institute (IRBV) from the University of Montreal to decontaminate plants using four land east of the city for four years.
Agriculture Canada has meanwhile heard for three years with the City of Lévis in May to upgrade a site near the old municipal incinerator. Switchgrass plants erected and reed canary grass were started and will be used as biomass for heating or transportation when they mature.
In a word
Phytoremediation: Phytoremediation is a remediation technique based on plants and their interactions with soil and microorganisms. This technique relates more particularly to water treatment and soil remediation.