A Mosaic sign stands outside the processing plant on the grounds of the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A mine shaft, right, and potash ore processing facility, left, stand on the grounds of the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A Mosaic logo appears on the hardhat of Ken Berg, production supervisor, at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A Mosaic logo appears on the shirt of Ken Berg, production supervisor, at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Production Manager Ken Berg illuminates the mine shaft wall as an elevator descends 3,000 ft. at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Production Manager Ken Berg waits for the elevator to settle at the bottom of a 3,000 ft. shaft at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A personelle vehicle sits in a tunnel in a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
An overhead light illuminates a section of wall in a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Wires run to a control panel in a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Production manager Ken Berg, right, says hello to a colleague waiting for a delivery of explosives in a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A personelle vehicle sits near the mine shaft in a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Production Manager Ken Berg fills out a vehicle log at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
An overhead crane operates in the maintenance area of a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Production Manager Ken Berg waves to a colleague as he drives through a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Vehicles travel through a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A set of air-lock doors open as a vehicle travels through a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Production Manager Ken Berg pulls a cord to activate a set of air-lock doors as he travels through a Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
The headlights of a Caterpillar underground mining loader shine in an otherwise pitch black Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A table sits in a work area at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Mine Technician Scott Cullins surveys for cutting guides in a section of tunnel being drilled at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
Mine Technician Scott Cullins, left, surveys for cutting guides in a section of tunnel being drilled at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker
A drill machine sits in a tunnell at the Mosaic Co. potash mine in Colonsay, Saskatchewan, Canada, on Tuesday, March 22, 2011. Photographer: Daniel Acker