This is 99% invisible. I'm Roman Mars.

Every day workers at grocery stores and convenience stores in Montana carry out a sad ritual.

First thing I do when I come on in is I go check the rotation on my milk and check my dates of course.

That's Ken Carson.

He's a dairy manager at a grocery store in Montana and every day when he gets in he checks the sell-by date on his milk.

If it's past the date, the milk must be thrown out.

These are all 20s that I'm pulling off. This one is dated the 18th and I will have to

pour this one down the drain. I have probably six of them. Ken is originally from

Washington State where he also worked in the grocery business.

When I came here four years ago, I had no idea that they were pouring down as much milk down the drain as they have been.

In fact, it was repulsive and sickening the first couple

of weeks here. It was hundreds of gallons. There's nothing wrong with it.

Pouring out milk happens to some extent in grocery stores all over the country.

That's reporter Meredith Hotenot.

But Montana throws much more of it down the drain than most places, because

the sell-by-date on the milk is required by state law to be just 12 days after pasturization.

The industry standard is 21 days.

After these 12 days, Montana law requires that the milk be thrown away.

It can't be sold or donated.

Seems such a waste.

We've got families that are in need when we're doing this.

Montana is throwing out so much milk, in fact. The price of milk there is about $2 per gallon

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