Tuesday, November 24, 2015

GREENWICH-MOHAWK REMEDIATION: Odour woes halt excavation work

Excavation work has been halted in a concentrated area of the Greenwich-Mohawk brownfield remediation site after intense odours were generated over the past two days.

The city announced Wednesday that cleanup work at the north end of the site at 347 Greenwich St. was stopped due to smells emanating from a heavy concentration of petroleum hydrocarbons. The odour had been magnified due to unseasonably mild temperatures combined with humidity and dense fog overnight Tuesday, according to a media release from the city.

On Wednesday morning, two large hand-painted signs on plywood were spotted propped up near the brownfield site, bemoaning the ongoing odour resulting from remediation work.

Red painted letters on one read: "How sick R we of the smell," while a second read: "Please stop. Fumes R making us sick."

The bad smells, which vary in description from heavy oil or asphalt to electrical or burning smells to a chemical stink, first became an issue in July. The stench results from excavation work in an area heavily contaminated by oil or petroleum hydrocarbons over many decades by industries long gone.

Residents in the Eagle Place and Echo Place neighbourhoods have complained about smells permeating their homes and of being unable to enjoy their properties as well as suffering from headaches and sore throats.

One Mohawk Street resident, who preferred her name not be used, said the recent worsening of the odour became "super strong" on Tuesday night.

"I got up this morning and I could still smell it in my garage," she said Wednesday morning.

"People are really tired of it," she said.

The resident said the city has done a good job of keeping neighbours informed and she understands that "before things get better they'll have to get worse."

On Wednesday, the city announced it was taking action to decrease the impact on area residents.

Excavation activities on the concentrated area were halted until further notice. And as of late Tuesday efforts have been focused on odour management and excavation on other areas of the site, further from neighbourhood properties.

The city said that an additional vacuum truck will remain on site and be dedicated to oil skimming operations.

As well, additional daily applications of odour suppressing foam will be used on problem surfaces, including stockpiles and excavation slopes.

The city also announced that it will reassess the work program to ensure that heavily concentrated areas are excavated at a future date when warm temperatures do not worsen odours.

Ministry of Environment representatives visited the site on Oct. 29 in response to odour complaints caused by high winds and a large volume of rain that fell on Oct. 28, said city spokesperson Maria Visocchi.

Officials confirmed that air quality levels remain consistent with ministry standards and all volatile organic compounds data collected to date is within ministry guidelines, she said.

Daily air monitoring is scheduled to continue through November.

As of Nov. 1, 83,000 cubic metres of soil had been treated either through bioremediation or a coarse material wash treatment, according to the city. In addition more than 100,000 litres of oil has been skimmed from the excavation water and recycled.

Last week, area residents also were notified via a letter in their mailboxes of work being done in the northeastern portion of 22 Mohawk St. involving the removal of a small area of xylene-impacted material. Xylene is a solvent found in petroleum, gasoline, coal and wood tar.

The material was taken to 66 Mohawk St. to be treated. That work was estimated to last two to three days and may have resulted in a "magic marker" smell to the air, according to the city.

Additional monitoring of air quality levels was conducted during that work and it was possible that workers in the immediate excavation area would be required to wear respirators, stated the letter to residents. Air monitoring indicated that no applicable ministry standards were exceeded, the city said.

Odour issues have been a concern since July, but smells became overpowering in September when workers hit a heavily contaminated oil pocket at 347 Greenwich St. The oil was nearly a quarter-inch thick. Excavation work was then temporarily stopped and workers concentrated on cleaning efforts and odour control.

The Greenwich-Mohawk site was once home to come of the city's biggest and best-known factories, including Massey, Cockshutt and Sternson. The site was heavily contaminated and the city is conducting a massive cleanup operation.

Remediation is expected to continue to the end of March but if more work is needed, it may continue to the end of December 2016.

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