remediation is an emerging field, and as such, substantial research
has yet to be done related to the feasibility for community groups of
pursuing remediation options to prepare land for planting. Thus far,
very few grassroots organizations that have undertaken such endeavours
and of the few community groups who have in fact remediating, most are
simply experimenting with process and have rarely planted crops for
consumption post-remediation. Remediating contaminated land remains
a domain largely in the hands of industry and government.
There are no straightforward solutions to the problem of brownfield
remediation for urban agriculture. Feasibility issues including accessibility,
cost, timeframe, effectiveness to remediate soil to agricultural standards
and environmental effects. The selection of an appropriate technique
will depend on the needs, capabilities and constraints of individual
groups as well as the particular soil characteristics, and the type
and degree of contamination present. There is no technique that will
be suitable to all groups and to all sorts of contamination problems.
In light of these limitations, we have identified excavation as the
most appropriate option for community groups to pursue at this time.
Because of the high health risk in the ingestion of food cultivated
in contaminated soil, we recommend that community groups exercise the
precautionary principle and employ excavation, the only feasible solution
guaranteed to provide nutritious produce grown in a contaminant-free
environment. It is accessible, cost- and time-effective, and represents
the least amount of risk in bringing soil up to agricultural standards
as well as maintaining these standards over the long term.
In light of this recommendation, we recognize the great future potential
of biological methods such as microbial and phytoremediation. Microbial
remediation and phytoremediation are very effective in removing the
majority of contamination in a given plot. They are also both cost-effective
and accessible to community groups. However, both techniques have demonstrated
difficulty in removing the final pollutants required to achieve agricultural-grade
soil. With more research and time, these methods have the prospective
of being risk-free and even more cost-effective than excavation, presenting
exciting options for the future.
Finally, by thinking creatively, community groups may wish to recast
the problem of brownfield remediation for urban agriculture as "brownfields
for urban agriculture" and pursue options that are not affected
by urban soil contamination at all. Examples include container gardening
and aquaponics. These techniques enable groups to achieve urban gardens,
but without the cost, time requirements and risk of soil remediation
at this time. Exploring such options makes urban agriculture feasible
in the interim while research into remediation for small-scale, low
budget urban projects develops and matures.
2002 McGill School
3534 University, Montreal, Quebec, Canada H3A 2A7