The twin stacks at the former Nanticoke Generating Station toppled over in a series of spectacular explosions in 2018.
Now, it’s the turn of the powerhouse that the stacks used to vent and which – not long ago – housed eight boiler units in what was the largest coal-fired generating station in North America.
Nanticoke and surrounding area were put on notice this week that the boiler house and turbine hall could be levelled as early as Aug. 19.
Weather will determine the timetable, as Ontario Power Generation and its demolition team want winds from the northwest to blow the dust plume towards Lake Erie.
“These are not the prevailing winds at this time of year,” Karim el-Khatib, director-general of operations for the salvage firm Delsan-AIM Environmental Services, said at a demolition open house on July 29 at the Nanticoke Community Centre. “We may have to wait as long as a week to get the right conditions.”
In recent months, Delsan-AIM has stripped the powerhouse down to its I-beam skeleton. The plan is to set off a number of charges from east to west that will tip the easterly three-quarters of the powerhouse to the north.
At the west end, charges will tip the section of the structure facing north to the north, while the selective catalytic reduction units – the “scrubbers” that were installed to remove nitrogen oxide from the coal-fired emissions – will keel over to the south.
Delsan-AIM’s el-Katib said the operation should be over in under 25 seconds.
“We dropped the stacks like a tree,” he said. “This is a similar structure, except it is much larger and made of steel. The shape charges cut the steel, while the TNT kicks the columns over.”
Rakowski Cartage and Wrecking of Winnipeg set the charges last year that brought down the 650-foot stacks. Rakowski has a lot of experience in western Canada in the mining industry. They will be back in Nanticoke for a return engagement in August.
OPG has played host to an open house in Nanticoke in advance of every critical phase of the demolition.
“That’s what we’ve been doing throughout this process so everyone knows what’s coming and everyone is prepared,” says engineer Joe Mateus, an electricity production manager with OPG.
As with the demolition of the stacks, an exclusion zone around the generating station will be in effect in the runup to the August explosions.
This includes 1,000 metres south into Lake Erie, 850 metres into the lake due west of the powerhouse, and 500 metres east into the former coal yard at the east end.
All roads into the plant will be closed and posted with security when the dynamiting is imminent. Security officers will keep unauthorized watercraft clear of the exclusion zone over the lake.
A series of sirens will signal the five-minute countdown to demolition. A final siren will sound one minute before detonation. Non-electric shock tubes will be used to detonate the charges. This will ensure that lightning or radio signals do not spark premature explosions.
Delsan-AIM has installed a floating membrane over the water intake on the west side of the powerhouse. This was done to prevent dust and debris from landing in water that Haldimand treats in Nanticoke and pumps into the municipal supply in Jarvis, Townsend, Hagersville and elsewhere.
At its peak, the 4,000-kilowatt generating station employed 650 people and paid $3 million a year in property taxes.
The plant burned its last lump of coal in 2013. The former Liberal government boasted that eliminating the Nanticoke station had an impact on air quality similar to taking seven million vehicles off the road.
The province announced the construction of the Nanticoke plant in 1968. OPG continues to produce electricity at the site by means of a 44-megawatt solar installation. OPG intends to have the Nanticoke site cleaned up by the summer of 2020.