Chemical that gives natural gas its smell spills in Montana, creating odor but no danger

Officials say there's no danger despite the smell of a gas leak near a northern Montana city. The only thing that leaked is the chemical that gives the gas its odor.

NorthWestern Energy says about 300 gallons of mercaptan (mer-KAP'-ten) spilled near the company's gas-gathering operation near Cut Bank. Natural gas is naturally odorless, so utilities add the chemical to give the gas its sulfuric smell that alerts people to a leak.

NorthWestern officials say the chemical doesn't present any danger to the public, although people nearby will have to put up with the unpleasant odor for a little while.

The cleanup is expected to extend into Thursday evening.