The Gatineau site of one of winter's most popular events in the capital was thrown into doubt earlier this year following the discovery of contaminated soil.
Winterlude's Snowflake Kingdom, the annual ice slide and sculpture event held in Jacques-Cartier Park, will go ahead in the same location this year.
But according to an NCC memo obtained by CBC through access to information, the site was left in a "much deteriorated condition" by the company that staged the MosaïCanada horticultural exhibit there in 2017 and 2018.
"Site conditions were concerning, and various exchanges were made to insist that health and safety requirements be respected onsite," according to the April 29 memo, prepared by NCC staff for CEO Tobi Nussbaum.
"Remediation to ensure safety for park users" was required, according to the memo, which also noted the Department of Canadian Heritage, which runs the Winterlude festivities, "has been informed of the low likelihood that they will be able to use the site for Winterlude 2020."
Canadian Heritage has since confirmed the 2020 event will take place in the park despite the contaminated soil.
In a statement, spokesperson Daniel Savoie said "it has been concluded that the level of contamination present on site … does not in any way affect the planned activities of Winterlude Snowflake Kingdom in Jacques-Cartier Park."
Company left park 'prematurely'
The park has been closed for rehabilitation work since the spring. The NCC said in a statement that the company behind the MosaïCanada event, Mosaïcultures internationales de Montréal, left the site prematurely and failed to return the park to its original condition before turning it over.
According to the NCC, the contamination was due to "historic industrial and commercial use" and existed long before MosaïCanada installed their giant plant sculptures. But when the exhibit upped sticks in 2018, the contaminated soil was exposed.
"While the contaminated soil did not pose any risk at that time to the public, the soil was disturbed and exposed following the Mosaïcultures internationales de Montréal events in 2017 and 2018," the statement reads.
When NCC inspectors visited the park after MosaïCanada wrapped up, they also found construction debris including electrical wires, culverts, rebar and an abandoned pump and shovel. In the memo, staff speculated the contaminated soil may have been exposed "when [Mosaïcultures internationales de Montréal] plowed the debris into the soil."
Mosaïcultures internationales de Montréal did not respond to CBC's request for comment.
According to the NCC memo, the company paid an $80,000 deposit, to be surrendered if the site wasn't returned to its original condition. The cost of the cleanup, which is due to begin in the spring, is expected to exceed that amount.