New provincial soil standards lead to renovations at community garden
By Travis Poland
Gardeners planning to sow their seeds at the city-owned Nanny Goat Hill Community Garden this spring have had their hopes squashed.
Lead and other toxins exceeding provincial standards were found during soil tests last year and now the city will close the garden until mid-summer to rehabilitate the area to mitigate any potential health risks related to soil contamination.
The project, expected to cost $700,000, involves covering the contaminated soil with filter cloth and a half-metre of clean soil before installing raised-bed gardens to prevent direct contact with any contamination, City of Ottawa environmental remediation advisor David Kiar told Centretown News by email.
Other improvement to the patch of green at the corner of Bronson and Laurier avenues, including a new gazebo, lighting, and an accessible shed and picnic table, are also being added during the soil cleanup, said Kiar.
The garden has been growing since 2000. Each year, nearly 1,000 people enter a lottery for one of the garden’s 110 plots.
Qi Wang, one of the garden’s coordinators, welcomes the changes even if it means the gardening season will be cut short.
“Given that we had to remediate the soil, this is a grand opportunity to make the garden as functional and as vibrant for us as a garden, and for us as a community,” said Wang.
“We’re eager to work with the city to firm up the details of what the redesign will look like,” she said.
Wang said the gazebo will be a refreshing resting place for gardeners and reinforce the garden’s role as a community space.
This isn’t the first time the city has dealt with contaminated soil at Nanny Goat Hill.
In 2010, 27 tonnes of contaminated soil and compost were taken from the site to a landfill after soil samples found boron, lead, and petroleum hydrocarbons.
Since then, provincial regulations have changed. Kiar said the new standards are more likely to err on the side of caution and standards for various individual contaminants are more stringent.
In 2016, city staff noticed the previous soil data was only evaluated against the old standards. After reviewing the data from 2009 and 2010, they found contaminants at Nanny Goat Hill that could pose a long-term risk to human health based the new standards.
Of the 54 soil sample locations at the site, including previous sampling, 25 had concentrations of polycyclic aromatic hydrocarbons exceeding provincial standards. Lead concentrations exceeding provincial standards were found in 13 samples in a grassy area and not the garden plots themselves, according to a city report.
Polycyclic aromatic hydrocarbons are a group of chemicals such as creosote that are generated when fuels, waste, and organic substances are not completely burned.
Martha Robinson, a program adviser with Ottawa Public Health, said people are exposed to polycyclic aromatic hydrocarbons on a regular basis via vehicle exhaust, cigarette smoke and camp fires.
“When it’s in the soil, it can cause irritation to the skin,” said Robinson.
“Long-term, it would be very unlikely, but if you were using your hands and it got in through your skin, it could be a carcinogen,” Robinson said.
Wang said gloves were offered to gardeners when the soil issues came to light and a sign at the garden reminds vegetable growers to wash their hands and produce.
The city has owned the property since the early 1980s. It was previously home to residential and office buildings. Records also suggest a private fuel outlet sat at the western edge of the site, the city report said.
Similar soil contamination has been known for decades at nearby LeBreton Flats. Previous decontamination efforts there have costs millions of dollars, and a large swath of the Flats will require millions more in soil remediation before the RendezVous LeBreton project — including a planned new NHL stadium — can proceed.