Ground Water Treatment
Waste and residual materials were disposed of directly in the bed of the St. Lawrence River in Montreal from 1866 to 1967. The governments of Canada and Quebec contracted Sanexen to design, construct, finance, maintain and implement a pumping and treatment system to treat toxic groundwater that was resurging into the St. Lawrence River over a period of 17 years. The average flow rate treated is 240 m3/day and a system of 32 pumping wells ensures hydraulic confinement. The client is Jacques Cartier and Champlain Bridges Incorporated in collaboration with the ministère du Développement durable, de l’Environnement et de la Lutte contre les changements climatiques (MDDELCC).
Decontamination of an Aluminium Smelter Site
Rio Tinto Alcan (RTA) contracted Sanexen to prepare and carry out environmental remediation work at its former plant located in Shawinigan.
The objective of the work consisted in the remediation of areas of the site not being used by RTA to comply with commercial and industrial uses, excavation and off-site disposal of residual materials and all soils presenting concentrations above the limit values identified.
The surface area of the RTA property is 224,300 m2, in which remediation work was carried out on approximately 69,650 m2. Work was performed over a period of 5 months in 2016 and approximately 200,000 m.t. of soils and residual materials were disposed of off site and replaced with clean backfill. Sanexen ensured that at the end of remediation and characterization work, all analytical results of soils samples taken from the excavation walls and bottoms of the remediated areas complied with limit values for the parameters analyzed.
Lac-Mégantic Rail Disaster
Following the derailment of a train with a convoy of 72 tank cars carrying crude oil, Sanexen mobilized their equipment and personnel for the emergency response that took place after the disaster. In the 5 months after the incident, Sanexen managed and treated liquids generated from firefighting and decontamination operations. Over 43 million litres of liquids were treated for clean water discharge into the Chaudière River. Sanexen worked in close collaboration with the government of Quebec, the municipality of Lac-Mégantic and other contractors present to provide professional services within difficult circumstances.