It's both, because it depends on whether it's just by virtue of its existence, or whether it's actually being used. So in some cases, like a wetland, it will be being used as a purification area.
On March 26th, 2009. See this statement in context.
On March 26th, 2009. See this statement in context.
Acting Assistant Deputy Minister, Environmental Stewardship Branch, Department of the Environment
It's both, because it depends on whether it's just by virtue of its existence, or whether it's actually being used. So in some cases, like a wetland, it will be being used as a purification area.
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