(Rouyn-Noranda) The Horne Foundry had until now only one limit to respect, for arsenic; she will now be in her twenties, La Presse has learned. The company will also have to put in place a multitude of control measures. And be more transparent.

Reduced releases of many contaminants, increased oversight and transparency; Quebec is tightening the screws on the Horne Foundry in Rouyn-Noranda and requiring it to comply within four years either with the standards in force or with the thresholds deemed acceptable by the National Institute of Public Health of Quebec.

In particular, the company will have to reduce the concentration of arsenic generated by its activities to a maximum annual average of 15 nanograms per cubic meter (ng/m⁠3) by 2027, stipulates its new five-year ministerial authorization that Quebec will unveil this Thursday and of which La Presse obtained the details.

The limit, which is currently 100 ng/m⁠3, will first increase to 65 ng/m⁠3 this year, then to 45 ng/m⁠3 for the years 2024 to 2026 – the concentration of arsenic in the air amounted to 73 ng/m⁠3 in 2022, the company reported last week1.

Quebec is also demanding that the company belonging to the Anglo-Swiss multinational Glencore submit a plan to reach the Quebec standard of 3 ng/m⁠3 by December 31, 2027.

The Horne Smelter will now have to respect limits for a multitude of other contaminants, including cadmium and lead, which are particularly toxic and which it emits in large quantities2.

The maximum authorized annual average concentrations will have to decrease gradually to reach the Québec standards in 2027 for these two contaminants, while the standard for nickel will apply as of this year.

In addition to annual limits, the company will also face daily limits from 2027 on key contaminants it releases, such as arsenic, cadmium, lead and nickel, as well as fine particulates and sulphur dioxide ; an annual limit will also be added for hexavalent chromium.

The Horne Smelter, which was not subject to any of these requirements until now because it began operations before they were adopted, will eventually be subject to operating conditions similar to those of a new industrial establishment, told La Presse an official who had access to the file, but who was not authorized to speak about it publicly.

The new ministerial authorization also tightens the requirements or adds new ones concerning the wastewater from the foundry, in particular concerning its content of copper, cadmium, zinc and hydrocarbons.

In particular, Quebec is demanding actions to reduce the toxicity of “final effluent” number 12, through which water from a foundry settling pond flows into Osisko Creek, then into Lake Rouyn.

Greater transparency is also required of the Horne Foundry, which will be required to publicly disclose the data from its air sampling stations, which it has refused to do until now, contenting itself with publishing an annual average – the measure will be effective 90 days after the issuance of its new authorization, this Thursday.

Sampling stations will be added, both by the Horne Foundry and by the Ministry of the Environment, the Fight against Climate Change, Wildlife and Parks, in order to have data on air quality. “360 degrees” around the company.

The management of the inputs used by the foundry in its process will also be improved: each delivery will be recorded, because the relationship between the arsenic content in the inputs and the arsenic concentration in the air is undeniable, estimates Quebec.

Characterization of the foundry soils and annual monitoring of the quality of groundwater in the area will also be carried out.

The new requirements imposed on the Horne Foundry receive a mixed reception from the Rouyn-Noranda citizens’ committee Stopping discharges and toxic emissions.

“The hopes are in four years”, when the limits imposed will be at their lowest, reacted its spokesperson Nicole Desgagnés.

A certain skepticism also remains as to the achievement of these new requirements: “We were so scalded that we have a hard time believing it,” said Ms. Desgagnés to La Presse.

It nevertheless welcomes the increase in the frequency of air sampling every two days, which will make it possible to partially fill a data gap which could mask certain significant peaks in contaminant releases.

The Horne Foundry declined to comment “on a matter for which no official announcement has been made,” spokeswoman Cindy Caouette said.

Rouyn-Noranda Mayor Diane Dallaire also did not respond, reserving her comments for the official announcement in which she will take part, her office said.