Urbanization and the Geoenvironment - Sustainable Practices in Geoenvironmental Engineering - page 259

Nickel

Copper

Zinc

Nickel

Copper

Zinc

Nickel

Removal after
treatment (%) Copper

Zinc

Nickel

Copper

Final concentration in
soil after treatment
(mg/kg)

Zinc

Nickel

Copper

Initial soil
concentration (mg/kg)

Zinc

Nickel

Copper

Zinc

Quebec “B” soil
Criteria concentration
(mg/kg)

Nickel

Copper

Zinc

0 200 400 600 800 1000

Metal content (mg/kg)

FIGURE 7.21
Remediation of a contaminated urban site using biosurfactants. (From Okoro C., Biosurfactant Enhanced
Remediation of a Mixed Contaminated Soil , MASc thesis, Concordia University, Montreal, Canada, 2006.)

7.5.2.1 Case Study of a Sustainable Urban Area

The Federation of Canadian Municipalities (FCM; http://www.fcm.ca) provides various
awards each year for a variety of concerns, including for innovative sustainability practices.
One of the awards for sustainable communities is for restoration of brownields. In 2013,
the Brownield project award was given to the City of Kingston in Canada for Belle Park, a
44-ha, multiuse recreational space. The site is a former landill where the city uses pumps
and extraction wells to capture the leachate that lows into the river. Since 2007, the city
initiated a new practice to plant 12,500 hybrid poplar trees and over 16,000 live stakes,
bareroot seedlings and potted shrubs as a means of capturing the leachate lowing to the
river and in the groundwater. The poplars uptake large volumes of groundwater contain-
ing the contaminants. Less leachate is now reaching the river, and over the long term,
there will be less need for the pump and treat systems. The solution is cost-effective and
the area provides societal beneits due to the transformation of the grass area into one with
many trees, and there are new pathways for walkers. There were various challenges for
the project. Owing to the harsh former landill environment, there were special require-
ments for tree care as regular irrigation methods could not be used as a result of the leach-
ate iniltration. The trees needed to be planted early in the rainy season before the heat of
the summer, to encourage growth as much as possible. In addition, early protection from