Discovery Channel HD

Mike Rowe submerges in a murky Florida river to pour concrete jackets around crumbling bridge pilings; in North Carolina, Mike sucks out a concrete washout pit and sprays sediment as he turns toxic sludge into potable water.

A group of four harpooners chase some of the highest-priced fish using only fast boats and aim; Niko must prove he can run a boat while Joe hunts to support his family as the fleet races to land the first bluefin worth thousands.

A vicious storm threatens to end the Misfits' season early; Issy attempts a new black-lighting technique to impress Opal Joe; the Digi Diggers mine is flooded, forcing the pair to scour the Outback for a new claim.

When Alaskan temperatures plunge, Todd and the team are caught by surprise; their biggest wash plant is frozen and the Hoffman's rush to thaw out their other plants before they're iced out for the season.

Hunter takes on the arctic tundra when a geologist's lead points to crazy gold on the edge of the Hoffman claim; Andy works to turn paydirt from an ancient river channel into a big payoff.

The Hoffmans discover a huge vein of gold that could save their season if they can get it out of the ground in time; as the mine equipment fails, pressure mounts on their mechanic, Randy, to keep it all running.

With their million-dollar goal in sight, the Hoffmans' best working wash plant breaks down and can't be repaired; Todd's last shot is to get the Hot Mess up and running during an arctic freeze.

As Alaska's brutal winter threatens to end his season, Todd only needs 47 more ounces of gold to reach his million-dollar goal; Todd works the night shift to keep paydirt moving; the final gold weigh might be a big win for Todd or another disaster.

When Freddy and Juan get an SOS from an Oregon couple's mine, they must unravel an underground mystery buried beneath a dried riverbed; facing misleading dredge tailings and a faulty homemade wash plant, the guys call in all-new tech as a final hope.

An all-female mine crew in Arizona struggles to mine for legendary riches with recycled water; as temps soar, Freddy and Juan scramble to build more efficient solutions and locate higher-grade gold in an attempt to triple the women's production.

Two miners in MT desperately need to double their gold after a disastrous start to the season; battling a personal crisis, Juan rejoins Freddy as they follow signs of old mining tunnels and use new technology to uncover ancient river channel gold.

Despite sitting in the epicenter of a BC gold rush, a mining couple's ground yields no gold; Freddy and Juan's limits are tested as the rescue becomes a two-plant upgrade; they face off against an overcomplicated wash plant nicknamed The Octopus.

Parker unleashes chaos as the team tries to get four wash plants running. Tony splurges on a new wash plant to get more gold. Kevin tries to broker a deal with his dad. Rick fires up at Vegas Valley.

Rick plows through Vegas Valley pay dirt and makes a big score, but an obstacle threatens to stall him; Parker's four-plant blitz stumbles; to keep his hot streak going, Tony pilfers more gear from his son Mike.

Parker drops the hammer as he tries to stop his gold slide. Rick makes a discovery that could end his Vegas Valley dreams. Kevin hires a new free agent and makes a big score at his new Sphinx Cut.

Rick makes a $1M call to open a new cut; Parker tasks Brennan with delivering more gold on Indian River; Tony re-engineers Paradise Hill's water system to get sluicing.

In the Yukon, Freddy and Juan tackle their most extensive treasure hunt yet; 288 claims across 6,000 acres and double the breakdowns; as the seconds tick away on the miner's season, the duo teams up with a local expert to find the gold.

Freddy and Juan return to the mighty Klondike to help a female mine boss and her husband bring their operation back from the brink of bankruptcy; with all-new ingenuity, the gold gurus attempt to upgrade the rusty old washplants efficiency.

Rick makes a $1M call to open a new cut; Parker tasks Brennan with delivering more gold on Indian River; Tony re-engineers Paradise Hill's water system to get sluicing.