I noticed this weekend a new community garden in the West End of Vancouver BC. The community garden is located on a former Shell gas station. Normally closed gas stations are fenced off and decontaminated over a period of years. I'm really surprised to see a community garden at this location. Does anyone have some insight about this garden?
Huh, not the sort of place I'd want to grow my veggies without some sort of assurances and a thorough knowledge of the reclamation methods on the site.
as long as the storage tanks have been removed and they weren't doing any leaking, before or during removal, and clean back-fill was used to fill in the areas where the tanks were, and any macadam/concrete was removed as well, then it should be fine to use for a garden - of non-edible things. not sure if i'd want to plant edibles the first few years. do you have some gov't group that oversees this kind of thing (removal of toxic stuff)?? if so, i'd check with them to see if the site has been cleaned properly and has been certified as safe to use for the purpose intended. even if the site was cleared properly and is deemed safe, i'd still wait a few years before planting edibles...especially in spots where the tanks were NOT located (where they were located should have nice fresh/clean soil now and shouldn't be a worry).
Doubt leaks from the station's fuel tanks will occur at all (a leaky fuel tank would be far too dangerous to permit it to happen!), but oil leaks from cars stopping at the station will be significant.
Anyplace where cars have come and gone in numbers for years will have asbestos from brake linings, used motor oil spills, maybe lead from when leaded gas was used etc. etc. unless all the soil was taken away and replaced with clean soil.
Leaks from vehicles are inevitable, but modern service stations here are required to have perimeter developments to contain them. Leaks from tanks are VERY common here. And the soil will have been contaminated by old leaks even if the tanks that were there since 1945 were leak-proof: contamination migrates somewhat, but never really goes away (or at least, not in just a few thousand years). But having said all that, development of an ex-service-station site in Vancouver will have required a remediation plan approved by both the provincial environment branch and the City's environmental dept, and actually implemented. It will have been based on test drilling, water sampling, and so on to determine the nature, location, and concentration of the contaminants. If I recall correctly, the environment dept will give you whatever data you want. It used to be located in a falling-down building just North of Broadway and south of City Hall. Don't tell them I sent you.