The Discovery Channel HD (Pacific)

The I-70 Eisenhower Tunnel closes in both directions as a 78-vehicle pileup creates mass chaos; Mountain Recovery and Stauffer's Towing battle high winds and slick roads to clear wreckage and keep major highways moving.

Parker and Tony set 13,000-ounce gold totals, sparking a battle to see who can mine the most and reigniting an old feud; Rick faces health issues and an uncertain future; a new player enters the Klondike fray.

Tony's crew sinks a bulldozer and two trucks in the Midas Cut while his grandson flirts with a rock truck driver; Parker pushes to get his second wash plant running; Buzz struggles to assemble a new plant.

Rick receives a life-altering diagnosis; Greenhorns push Tony to his breaking point; Parker fires up a third plant and gets surprising gold results.

Tony ambushes Rick with a secret offer. With high hopes, Parker's crew fires up a fourth plant in the Quagmire Cut. Buzz bets on White Channel pay.

Competing companies team up to recover a fully loaded cement truck leaking natural gas; Big Jon heads into avalanche country to rescue a stuck semi carrying hazardous goods; during a sudden blizzard, a crash in Salt Lake City leaves a semi in pieces.