The floor of Bedford Basin is still littered with ammunition scattered by the explosion of a military magazine more than seven decades ago.
The July 1945 blast started when a barge at the Bedford Magazine jetty caught fire and blew up.
“We know, for sure, that there’s thousands and thousands of rounds of ammunition that were dumped in the Basin that never got recovered,” John McCallum, an explosives expert and chemistry lecturer at the Royal Military College, told a group of oceanographers Tuesday at Dalhousie University.
Some of the large piles of ammunition at the magazine didn’t explode in the fire, said McCallum, a former military ammunition technical officer and retired major who used to be the commanding officer of Canadian Forces Ammunition Depot in Bedford.
“If the depot had completely blown up, we’d probably be referring to Magazine Cove instead of Magazine Hill,” he said.
The blast sent more than 40 types of ammunition flying into the Basin, he said.
“They range from small arms .303 up to six-inch naval artillery,” McCallum said. “There’s torpedo warheads, depth charges, sea mines, anti-submarine mortars and very large numbers of a variety of mid-range cannon ammunition — 20- to 40-millimetre stuff. Most of it was never recovered because divers, at the time, were hardhat divers. So they couldn’t bend over and pick up stuff. If you couldn’t recover it from water up to your chest or by hook-and-line from a boat, it got left behind. So there’s ammunition scattered up and down the shore to this day.”
McCallum, who is working on his PhD, spent time in the Basin in August of 2015 collecting sediment samples.
“I did not drop this anchor,” he said, pointing to a slide of a shiny new dinghy anchor in shallow water near two pieces of old ammunition.
“I reached down over the side of the inflatable boat in a metre of water and placed it there very carefully because right here is a four-inch naval artillery shell, and this is the broken-off nose filled with concrete of an anti-submarine training projectile … If I had stepped out of the boat in chest waders, every place I put a foot I probably would have touched ammunition. It’s that kind of volume along that shore.”
Areas near the shore have been scrubbed clean by wave action, McCallum said.
“So most of (the ammunition) is visible. Lots of encrustation on it, but there’s lots of it there. Lots and lots.”
Two islands in the Basin are also littered with ammunition, he said.
“So there’s a huge footprint out there — probably two kilometres, two-and-a-half kilometres — where that ammunition … is still there, much of it undisturbed.”
McCallum didn’t paint the situation as particularly dire or completely safe.
“There’s not very much chance of stuff blowing up on people,” he said.
“But the problem is that it’s still around, and there’s this sense that everybody thinks that if it’s been in the water for 70 years, it can’t go off. But that’s not the case. The vast majority of munitions, especially the secondary explosives — that’s the TNTs and the RDXs and stuff — that stuff’s as good as the day it was made.”
Weapons on the seafloor all over the Earth
Japan has invested a huge amount of money clearing explosives from a bay where a lot of fishing activity took place, he said.
“The folks were actually eating poisoned seafood,” McCallum said.
“So they went to work and they built equipment and they literally recovered every single item in that bay. And they put it into an explosive chamber and they blew it up inside the chamber. So they could actually do it on board a ship. It was an amazingly expensive process, but they got the bay clean to the point where the marine life was safe again to eat.”
But it’s not clear yet whether cleaning up explosives on the sea floor is the right solution, McCallum said.
If explosives are buried deep in sediment, “you can imagine that it’s not necessarily better to disrupt it further,” he said.
Besides talking about Bedford Basin, he spent much of the talk describing spots off Nova Scotia and other parts of the world including Japan, Australia, the eastern seaboard of North America, and the western coast of Europe, where navies dumped weapons intentionally after the First and Second World Wars.
“If we were lucky and it was in the deep trenches, we’d just wait it out,” McCallum said. “But unfortunately it was put in places around the edge of the continental shelf or on the banks themselves, and that’s the bad news … We don’t even know the problem yet, let alone (whether) the solution is to clean it up.”
That said, McCallum made one particularly scary point about explosives dumped in a deep undersea trench between Ireland and Scotland called Beaufort’s Dyke.
“The Brits have been dumping ammunition into this 312-metre deep submarine canyon for probably 200 years by now,” he said. “The estimates are there’s at least a million tons of a mix of conventional and chemical weapons in there. And other estimates put it as high as two and a half million. So huge, huge amounts.”
The Brits have about a dozen seismic monitoring stations within 150 kilometres of the site, he said.
“A paper was published a few years ago by a geological researcher that basically pointed out that they had taken 20 years worth of seismic events recorded on their equipment and they had crossed referenced it with navy exercises and air force exercises and military and construction events and pipeline seismic survey stuff — everything. And they had eliminated and cross-referenced all these events that they could find. And they came up with about 18 or 20 that were left that they had no explanation for. But interestingly enough, they could all be triangulated back to the Beaufort’s Dyke. So, for those of us that are in the munitions business, we think that with probably tens of millions of shells in there, some of which undoubtedly had iron picrate salts in there, that you’re getting sort of random explosions.”
Two ships a day unloading
McCallum has not been able to find an exact record of how much of the magazine’s ammunition was blown into the Basin.
“I used to be the commanding officer of the joint. To this day, when we get two or three ships that come in one after the other over a three-day period, it will take us a week to sort out the records of what was landed,” McCallum said.
In 1945, “these guys were getting two ships a day coming in and unloading. Huge amounts of that stuff, I’m sure, never got listed in the records. It simply was blown out in the Basin.”
The Bedford Magazine was built after two other military sites on Halifax Harbour passed their best before date.
Fort Clarence, a military installation located in Dartmouth across from Georges Island (where the Imperial Oil refinery was), was an ammunition storage point for the army until 1927, McCallum said.
And the navy had an ammunition storage depot at Georges Island until 1927, he said. “But they hadn’t spent any money on it in … 150 years and the conditions had deteriorated badly.”
The two facilities no longer had any military relevance, other than storing ammunition, McCallum said.
“So there was a decision made in 1919 or 1920 to buy land in the Bedford Basin to establish a new joint services magazine.”
The military later bought two more chunks of land to expand the facility, he said.
“By the time they were done expanding, they were up to about 110 buildings.”
The Second World War “for Canada on the East Coast pretty much came to an end on VE Day on May 8 (1945). So between the end of May and the middle of July, they had 84 ships come back to demobilize and dump all of their ammunition.”
Ships carried huge numbers of depth charges because that was the only way to fight off German U-boats, he said.
“They were used like confetti,” he said.
“There was a story in World War Two of U-427 that survived an attack over a period of 16 or 18 hours of 678 depth charges. You’d think the crew would get tired of counting the bangs. But the submarine survived and went away. Those things had to be within 20 feet of a submarine’s hull to do any serious damage.”
Before the 1945 explosion, ammunition was stacked all over the place at the Bedford Magazine.
“Inside the buildings they were packed floor-to-ceiling, wall-to-wall. It was just an incredible mess in terms of safety concerns.”
The first explosion took place at about 6:10pm on July 18, 1945, said McCallum, flashing a slide on a screen showing a mushroom cloud produced by the blast.
“It carried on all night with that kind of impressive display,” he said.
When dawn arrived, the 120-metre-long jetty where the fire had begun was pretty much gone.
“It was just total, total, total devastation,” McCallum said.
“There wasn’t a single building left in the south end (of the magazine) that was really salvageable. It doesn’t so much remind you of anything so much as World War I battlefield because there was hundreds and hundreds of explosions over a period of 20 hours.”
Surprisingly, only one person was killed by the blasts.
“One of the night patrolmen, a guy named Harry Craig, raced up from the jetty to report the fire at the guard house and get the fire guys on the way, and then took a fire extinguisher and rushed back down to the jetty to do what he could. His body was found the next day under a sheet of corrugated steel, intact, but obviously the concussion had been the death of him.”
People fought fires at the magazine for days afterward, McCallum said.
“Apparently they fought brush fires for almost three weeks with up to 200 sailors at any given time.”
One of several craters created by the explosions was 60 metres across and 27 metres deep, he said. “It took about 250 depth charges at 130 kilos each to dig that crater.”
Some of the timber-framed buildings were completely gone the next day, sometimes leaving neat stacks of unexploded ordnance as telltale sign of where they once stood. “This was a massive, massive devastation.”
The military needed to clear away huge piles of rock, debris, soil, building parts, and ammunition, he said.
“It was a hell of a mess,” McCallum said.
“The only way into it was hydraulic mining because a bulldozer was the kind of thing that, basically, would trigger a fused round. So you couldn’t cut in with a bulldozer.”