Soil Picture Mostly Murky

Soil study in St. John's suggests we'll find contaminants if we look

The Issue: Better Grasp Would Be Helpful

Cape Breton Post Editorial
Wed., Mar. 31, 2004

Three years ago, the City of Calgary released an environmental study of the picturesque suburban subdivision of Lynnview Ridge where residents had become concerned about a possible legacy of contamination left when an Imperial Oil refinery closed there in 1975. Sure enough, the report documented levels of lead and benzene exceeding soil quality guidelines of the Canadian Council of Ministers of the Environment, setting events in motion that would culminate in a home buyout costing Imperial tens of millions of dollars.

Among the findings that prompted immediate alarm was a lead concentration as high as 1,260 milligrams per kilogram (or parts per million) of soil, nine times higher than the CCME guideline of 140. Lynnview Ridge thus entered the environmental lexicon as an example where soil contamination in excess of the CCME guidelines had led to costly remediation and relocation. Lynnview Ridge stands in contrast, it could be argued, to the Muggah Creek situation where so-called made-in-Sydney guidelines have been used to rebuff calls for relocation and general remediation in the perimeter of the steel plant and coke ovens footprint.

"It's shocking, isn't it?" said Lynnview resident Brad Smith when the report on his neighbourhood came out. "How many other 1,200 areas are there?" Actually, there could be quite a lot that we just don't know about. That's one implication from the recent work of scientist Trevor Bell and his team at Memorial University in St. John's whose soil testing in the Newfoundland capital last summer has raised new concern about urban soil contamination.

The Bell group took 260 soil samples, finding elevated levels of metals in playgrounds, parks, school grounds, open areas and residential properties around the city. Sixty per cent of the samples exceeded CCME guidelines for lead, and 26 per cent also exceeded the more forgiving U.S. Environmental Protection Agency's guideline of 400 parts per million for soil in play areas.

For residential properties in the downtown core, the median value (half were higher and half were lower) was 1,076, about 7.5 times the CCME guideline, which puts the oldest part of St. John's within the ballpark that caused such a commotion in Calgary. Bell notes that the 60 per cent of tests exceeding CCME guidelines in St. John's compares to only 25 per cent in Victoria, B.C., the only other major city to have such a study done.

The numbers for the St. John's core appear to indicate heavier lead contamination than generally showed up in soil tests around the Sydney cleanup perimeter.

Bell's work so far highlights lead, a known neurological health risk to children, which is assumed to be ubiquitous in urban environments thanks to leaded gasolines (banned only in the 1980s) and paints, as well as coal-burning, some industrial processes and natural occurrences of the metal in bedrock. However, Bell's team did test also for other metals, finding samples exceeding CCME guidelines for arsenic, barium, beryllium, chromium, copper, nickel and zinc. Only cadmium and cobalt stayed under the CCME numbers.

What does it all mean? To some it suggests a need for comprehensive soil testing throughout urban areas of the country. Governments are not eager to open such a potential Pandora's Box but there are sensible, low-cost measures that could be taken to minimize exposure to environmental contaminants if people were more aware of what's actually around them. No one's suggesting that we relocate Toronto.

A better grasp of the distribution of potentially harmful metals and other manmade chemicals in the soil, water and air of typical urban neighbourhoods, and what that means for human health, would provide a helpful context when environmental alarms, such as over the tar ponds or New Waterford hospital renovations, spring upon the public as things unique and unprecedented.