FORT McCOY, Wis. — Wednesday morning didn’t so much dawn as burn off the fog of southwest Wisconsin.

It was a big day for the 833rd Engineer Company. They drove onto the “lanes” for IED training in sand-colored Humvees.

Improvised explosive devices, or IEDs, are a major threat to soldiers in Iraq. They’re what the 833rd is training to handle. One of the key steps is knowing what to do when, despite all efforts, one goes off.

Wednesday’s IED training involved half the company. The other half runs one day behind. It’s the only way to process so many soldiers through such critical training. The soldiers drove down a yellow dirt road. Clusters of mock buildings suggested small Iraqi towns. People came out of the buildings to greet the convoy each time, waving from the side of the road. Others came out to fight. They hid.

Soldiers heard a loud bang and a plume of smoke from the roadside when the bombs detonated. The bomb used in training isn’t anywhere near as strong as those used by Iraqi insurgents, but you still feel the shock through the armor.

Each convoy pulled back to the stricken vehicle, surrounding it. They towed it clear as fast as possible, clearing the kill zone.

It is sweltering inside the Humvees. Sweat rolls into your eyes and the stink of diesel wafts through the air. It gets louder if insurgents decide to shoot at you. The sound of rifle fire from outside penetrates into the vehicle. Hammering gunfire echoes inside when the gunners sight the insurgents, pounding at your ears.

Our gunner has a sense of humor. It starts sprinkling for a minute.

“That rain feels good,” he calls inside.

Three voices ring out immediately: “Shut up, Wies!”

There’s no guaranteed shower and clean uniform after the training. The soldiers return to their tents, long arches of tan. The temperature inside depends on whether the tent is open or closed. Closed tents are still, close spaces. They smell of damp towels and sweaty uniforms. Open tents smell similar, but they’re cooler.

The soldiers wear 60-pound vests with ceramic plates for protection. They put winter coats to shame with their ability to hold heat in. “Drink water” is the common refrain.

“There’s only one way to get used to it, that’s to wear it all the time,” said Capt. Ben Lampe, the company’s commanding officer. “It’s all about the culture shock.”

The soldiers are upbeat. They laugh and joke during breaks. Their faces light up when they talk about Pella Corp.’s donation that will pay for them to come home for a few days in August.

Pvt. Mark Straube will return to his home just outside Ottumwa. Family in Iowa is his mom and four brothers. His father and two stepsisters are in Florida. Loved ones are always on the soldiers’ minds. They call or write when they can.