At 9 a.m. Thursday morning, emergency vehicles surrounded Breckenridge and Dillon Valley elementary schools. One by one, more than 20 people fell victim to a food-borne toxin and were raced to the hospital.

Fortunately, this was only a drill.

The mock emergency was staged by local agencies, a chance for them to practice working as a team and hone response procedures in advance of an actual disaster.

“It is an opportunity for us to see how does it really work in the field,” asst. county manager Scott Vargo said. “We take these as opportunities to put in place what we may have learned on paper. I think it’s well worth all of the effort and time that people put into it.”

Which is considerable.

The exercise, an annual undertaking, brought together dozens of volunteers who played the role of the victims as well as personnel from the Summit County Sheriff’s Office, local fire districts, the coroner’s office, the Summit School District, Summit Medical Center, Summit Ambulance and others.

Each year the plot of the exercise is a little different, allowing the agencies to coordinate in different ways and to respond to different challenges.

The extra hands-on practice has paid off before. Last year’s mock emergency, a chairlift accident, was staged at Keystone Resort just weeks before a real wildfire broke out in the same area.

“We just fell into our roles that we had just practiced,” Lake Dillon Fire-Rescue spokesman Steve Lipsher said of the public information officers who worked on both the practice and the actual emergency. “That worked out beautifully.”

This year’s food-borne illness exercise, reminiscent of the H1N1 outbreak a few years ago, gave local agencies a chance to tackle a new challenge – turning command over from fire and law enforcement over to the departments of environmental health and public health, agencies normally not involved in the emergency exercises.

The exercise imagined a barbecue for an elementary school basketball team at which potatoes tainted with botulism were served. With an incubation period of 12-36 hours, the actors began feeling “symptoms” the following morning, just as the students were arriving at school.

Twenty-one people were transported to Summit Medical Center as part of the exercise and two adult actors, both playing 10-year-old boys, died in the script.

The complex drill allowed emergency agencies to coordinate their efforts, meet and work with individuals from other agencies, test various notification systems and iron out any kinks in the process.

“The value of all of these exercises is their unpredictability,” Lipsher said. “When we have a catastrophe, there are going to be things that don’t work right and we’re going to have to be flexible, responsive, reactive, fast on our feet and we’re going to have to deal with things the best we possibly can. I think one of the great values of an exercise like this is that when the curve balls come, you have to learn to think.”