Vale slag dumping causes 'concussion of sound'

Vale said the source of a loud noise heard by many in the city during the afternoon of Jan. 5 was the company's slag dumping operations.

“There was a loud ‘pop’ at our slag dump off Big Nickel Road around 5:30 last night due to the hot slag hitting the cold ground in extreme cold temperatures,” said Angie Robson, manager of corporate affairs for Vale’s Ontario Operations, in an email statement.

“This is not uncommon when we dump slag in cold weather, and the hot slag hitting the cold ground will typically cause a large plume of steam.

“While our operators did report a concussion of sound, we are frankly surprised by the impact that has been reported in the community and we are looking into this. There was no damage to any of our equipment and no injury to our people.”