Client: Henkel Canada Limited
Location: 162 Ward Ave. Hamilton, ON Bounded by TH&B, residences on Ward Ave. and Royal Ave. and a schoolyard
In 1994, Henkel Canada Limited purchased the former organic chemical plant as a "brownfields" site, with contaminants in soil and groundwater from a factory dating from 1945. As Engineering Manager for the international consulting firm retained for the work, John McGlone supervised a team of four professionals to design, construct and operate a Soil Vapour Extraction (SVE) system to vent and treat the vapours from soil and groundwater contaminants. These included chlorinated compounds, and petroleum hydrocarbons such as toluene, ketones and SVOCs.
The work involved public consultation, design, construction, investigation of potential for migration to municipal sewers and the study of the consequence of the presence of methane in the subsurface. The building and equipment were designed as explosion-proof to accommodate the volatile vapors.
Toluene and other volatile compounds were shown to have migrated northeast of the site towards soil below McMaster University, located hydraulically down-gradient. The toluene concentrations were greater than 10,000 ug/L in shallow groundwater, compared to MOE Table B criterion of 5900 ug/L for groundwater below the homes between the site and the University. Residents were concerned.
The SVE system operated effectively to reduce the source of toluene vapour migration in groundwater.
As the operation of the SVE system continued, monitoring and risk assessment by others showed a reduction in vapour concentrations to acceptable levels before reaching any exposure pathway.
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