An East Kootenay man will hunt for a fabled gold boulder in the deep waters of British Columbia’s Kootenay Lake — using a submarine he built himself. By Vince Hempsall

On April 23, 1894, an article ran in the Nelson Tribune newspaper about a boulder of gold Randal Kemp discovered near Crawford Bay, on the shores of Kootenay Lake. Kemp said it measured 68 x 35 x 30 centimetres, about the size of a microwave, and estimated it was 1,300 kilograms. Its size was never proven because while Kemp was lowering it down a slope onto a boat, his rope snapped. The boulder sank to the bottom of the 400-foot-deep lake. The story could have been a hoax made up by Kemp, but that hasn’t stopped scuba divers from attempting to find the boulder in recent decades. None have been successful. But this spring, a Fairmont Hot Springs, British Columbia, man is hoping to locate it with the help of his homemade submarine.

Hank Pronk started building submersibles as a hobby when he was 16, and now, at the age of 59, he’s created his eighth one. He called it the Elementary 3000 because, he says, “It’s the world’s deepest-diving homemade submarine that’s pressure-tested to 3,000 feet.” The rating comes from a test done at a pressure chamber in Vancouver, but the deepest his submarine has physically travelled is 1,000 feet in the West Kootenay’s Slocan Lake last year. Pronk built the all-electric steel sub to American Bureau of Shipping standards, and it features a robotic arm, dome window, camera, buoyancy tanks, backup air supplies, and thrusters that operate off two golf-cart batteries. The craft is 3.3 × 1.8 metres, weighs 1,360 kilograms, and the interior is big enough to fit Pronk’s six-foot frame comfortably when he’s seated in a cross-legged, upright position. He says he can explore about 1.6 kilometres underwater on one battery charge, and aside from hunting for gold this spring, he’s also planning to shoot footage of the wreck of the SS City of Ainsworth paddlewheeler, which sank in 1898 near Kaslo, British Columbia, and look for a fabled boxcar of silver ingots on the east side of Kootenay Lake.

As for how he transports the submarine, Pronk owns a house-moving company and says he’s used to winching and transporting large objects. For the engineering aspects of building submarines, though, he learned almost everything either online or in books. And how much did the Elementary 3000 cost him to build? “If I told you, you might tell your wife, and then she might tell my wife,” he says, “and then I’d be in trouble.” Unless, of course, he finds that gold boulder.