The City of Hamilton has experienced further delays on its massive wastewater treatment plant upgrades after discovering a “significant amount” of polychlorinated biphenyl (PCBs) in the soil around a new chlorine contact tank, a city staff report says.
The staff report by Hamilton Water and Public Works Director Andrew Grice states that in an effort to reduce costs and construction delays on the $340-million upgrades to the Woodward Wastewater Treatment Plant, the City is partnering with the province to separate, sample and haul the hazardous soil.
“The city’s project team is closely monitoring the situation and won’t know the full cost and schedule impacts until the excavation work is complete,” Grice wrote in a public works committee report.
According to inquiries from The Hamilton Spectator to the Ontario Ministry of Environment,Conservation and Parks, the newly discovered 6,000 tonnes of polluted soil came from an old landfill site that closed in the 1970s prior to modern hazardous waste laws.
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While Hamilton’s ongoing wastewater upgrades were expected to be completed by December 2021, city officials say the discovery of PCBs may alter that timeline.
The wastewater treatment plant upgrades represent the city’s largest ever infrastructure project and a major step forward towards delisting Hamilton Harbour as an Area of Concern.
Upwards of 300 workers are currently on site for the upgrade project, which essentially has three primary components: first, is an $88-million new main wastewater pumping station being constructed by Maple Ball Joint Venture and includes the installation of 12 – 700 horsepower pumps for a total firm capacity of 1,700 million litres per day; second, are the $61-million electrical and chlorination upgrades contract being undertaken by Alberici Constructors; third, are the tertiary treatment project upgrades intended to have a major impact on water quality in Hamilton Harbour. It is a $165-million construction contract awarded to North American Construction that involves a number of sub-projects.
Biosolid Management Project Success
In more positive news for the Woodward Wastewater Treatment Plant, city officials announced that a newly-installed thermal drying system will bring 30 years of environmental, social and economic benefits to the City of Hamilton. The new facility will use a thermal drying system that takes nutrient-rich organic materials that results from the wastewater treatment process and turns them into pellets to be sold for fertilizer or fuel.
Hamilton produces about 43,000 wet tonnes of biosolids per year, according to city reports. The new technology involves heating the biosolids in a large Andritz Drum Dryer System and selling the resulting dried product. This will also reduce odours and decrease the volume of the city’s biosolids by approximately 75%, which significantly reduces the number of trucks to haul the material off site.
“The completion of the Biosolid Management Project is an important milestone for the City of Hamilton and we are excited to participate in a sustainably driven, emerging sector,” Hamilton Mayor Fred Eisenberger said in a statement.
The facility is a public-private-partnership funded by Infrastructure Canada under the P3 Canada Fund. Construction and continued maintenance of the new facility will be led by Harbour City Solutions.
The overall life cycle investment by the city over the 30-year term is approximately $245 million.