West was one of the first of local law enforcement officers to enter the school after dispatchers reported there were two "gunmen" in the building.
Officers knew the exercise was a drill, but they didn't know what to expect.
The exercise, to some degree, took them by surprise.
"Upon the arrival of the first five officers, we did what the first responders usually do," West said. "We went in, we found the people doing the shooting, and we eliminated the threat."
From there, officers worked at securing the school grounds and assisted ambulance and other personnel in removing both "fatalities" and "wounded" subjects found in the building.
"I was with the first team that went into the school," West said. "We've been told this time and time again � the first team's function is to leave the wounded and go on to find the shooter."
That, West discovered, was extremely difficult.
"Leaving the wounded was probably the hardest thing in my mind to do," he said. "You are there, and you hear people begging for help, and you have to bypass them."
Officers knew no one was truly injured. But the atmosphere created by both the planners of the exercise, and local actors who helped stage it by posing as either the two shooters in the building, or the wounded and injured, was surreal.
"When you go into a situation like this, you never know what's going to happen," West said. "Obviously, the people who do this in an actual situation, their mindset is not quite right, but I guess you expect the unexpected, and hopefully we can adapt quick enough to deal with it."
With the drill having been completed for only about an hour, West admitted that he was still comprehending and reflecting on the lessons he learned � while at the same time, trying to battle the personal jangle his body was still feeling from all of the excitement.
"I think I learned that if I'm ever in an actual situation like this, there will be personal feelings I will have to overcome," he said, "and I'll have to do what I'm trained to do.
"We train in a lot of different scenarios," West said, "and one of the first things we learn is that you have to keep yourself under control in order to keep everyone else in control."
Staying in control was extremely difficult, because of the realism that planners added to Friday's exercise.
The wounded were covered in red. It wasn't real blood, of course, but it looked exactly like it.
The injured screamed for help. Although no shots were fired, a tape recorder placed in the building played the sound of pistol shots echoing through the hallways.
"We were constantly reminding each other that we had to go through the building quickly, but at the same time, we had to remain safe," West said. "It's just like any other adrenalin rush you get. It clouds your judgment."
Jolene Reule exited the school and walked to the command center following the exercise; the large splotch of red paint on her neck indicated where she was wounded during Friday's simulation.
"I was victim," she said. "I was just wounded and they got me over to the Vermillion Hospital, and from there they would have shipped me off to a hospital either in Sioux Falls or Sioux City if this had been real."
There were more than local police cars buzzing around the school. Ambulances from Wakonda, Elk Point and Vermillion parked in a line on a nearby street, and transported the wounded to the Sanford Vermillion Hospital's emergency room.
Air ambulances also flew over the scene. Members of the Vermillion Volunteer Fire Department parked their large red trucks at key intersections close to the school building, keeping innocent pedestrians away.
Reule, who volunteered to take part in the drill, said she and other participants received a full briefing in advance from the exercise's planners.
"It was still more intense than I had expected," she said. "It was scary in there, and it was interesting to see how the police responded and how the triage was set up.
"I think something like this, if it really happened, would definitely have an impact on the systems in Vermillion," she said.
In light of the Virginia Tech shootings that occurred earlier this spring, Reule said participating in the mock shooting provided her with some peace of mind.
"I think being in this and seeing how well people respond to this � no matter what, it's going to be dramatic, but it's nice to see the community is actually taking the steps to prepare for it," she said.
"I thought things went very well," Vermillion Police Chief Art Mabry said. "We had some things thrown at us that we weren't necessarily anticipating.
"This scenario was planned by just one person, and nobody else (in law enforcement) knew about the details," he added.
Officers encountered some of the same obstacles that law enforcement at Virginia Tech had to face. Doors were chained, and had to be opened with bolt cutters.
"Unfortunately, you learn from tragedies like Virginia Tech and Columbine," Mabry said. "The nice thing about a mock exercise is we learned a few things here that we could do better, but nobody got hurt in the process."