The biggest blast in Ottawa’s history was over in seconds on Sunday, reducing the 11-storey John Carling Building to 40,000 tonnes of rubble by 420 kilograms of explosives. <br /> <br />Hundreds of people gathered 300 metres away from the federal office tower at 930 Carling Ave. that overlooked Dow’s Lake to catch a glimpse of the $4.8 million demolition.
