Imagine if the unthinkable happened - a catastrophe at the Comanche Peak Nuclear Power Plant.

Last week plant workers, city and county public officials, law enforcement authorities and representatives of school districts and hospitals dealt with that very real possibility in a drill that involved Somervell and Hood counties.

This was the scenario:

At 9:53 a.m. last Wednesday, Luminant Power declared a general emergency at Comanche Peak. High radiation levels were detected inside Unit 1, indicative of “failed fuel.” Unit 1 had been shut down, but a radioactive release was taking place.

Local, state and federal officials were notified and kept informed of plant conditions. Plant employees not needed to respond to the emergency were evacuated from the facility.

People within two to 10 miles downwind of the plant were advised to seek shelter indoors and listen to the Emergency Alert System on WBAP, 820 AM.

Adding to the sense of realism was the memory of the March disaster that played out at the Fukushima Dai-ichi Plant in Japan.

The drill began early Wednesday morning with phone calls to public officials, emergency preparedness coordinators, law enforcement authorities and school and medical personnel in Glen Rose and in Granbury. It wasn’t a surprise - participants knew the drill would happen that day - but they didn’t know the exact scenario until the call came.

In Glen Rose, officials rushed to the Emergency Operations Command set up in a room at the Somervell County Sheriff’s Department. In Granbury, Hood County’s EOC was set up in a room at the Law Enforcement Center. A Joint Information Center to disseminate information about the event was staged at Granbury City Hall.

The Glen Rose Reporter visited all three locations as the drill unfolded to get a full picture of the drill’s scope.

At the Law Enforcement Center in Granbury, about 30 people sat at rows of long tables with banks of phones and watched a map on a screen of the area. It felt like Mission Control or a war room.

County Judge Darrell Cockerham stood up to give a briefing at 10:03 a.m.

Residents had not been evacuated, he told the drill participants. Radio and TV stations had been notified, as had school officials. Two people with special needs were taken to the senior center. Road crews were waiting. Traffic was being monitored. Everything was on emergency standby.

Then Matt Bozeman of Comanche Peak got a phone call and announced to the participants that the containment pressure in Unit 1 was still “pretty high."

He added: "So I think they’re doing some radiological assessments associated with that.”

The center received word that the situation has gone to a general emergency because of a loss of two barriers and the potential loss of a third in Unit 1.

“That concludes the briefing,” Judge Cockerham said. “This is a drill.”

The U.S. Nuclear Regulatory Commission requires such exhaustive drills every two years.

“They try to design one that goes through all the levels and exercises everything in the plan,” Bozeman said.

Meanwhile, over at the Joint Information Center, a briefing for the news media was underway at 11 a.m. Comanche Peak Plant Manager Steve Smith and JIC Director Sid Underwood took questions along with Dub Gillum, Texas Department of Public Safety spokesman; Bob Blessing, Hood County’s spokesperson; and Lisa Rudigan, a health physicist with the Texas Department of State Health Services Radiation Control. Fake reporters representing media outlets such as the Fort Worth Star-Telegram, the Austin American-Statesman and the Glen Rose Reporter asked questions.

First, though, Smith gave a quick update.

“We do have a radiation release in Unit 1,” he said. “It’s coming from an emergency airlock.”

A team was working to spray water to mitigate the impact, he said. The current pressure in the containment building was 28 pounds. The spent fuel cooling system also was out of service, he reported. In 31 hours the pool would start to boil.

Relocation centers were set up in Stephenville, Cleburne and Benbrook. The wind was blowing to the northeast, so the folks in Hood County would send their evacuees to Erath County.

At the Somervell County EOC, County Judge Mike Ford and his secretary, Pat Schneider, Mayor Jean King, Councilman Dennis Moore, City Superintendent Ronald Bruce, County Commissioner John Curtis, Sheriff Greg Doyle, sheriff’s department employees Jo Spurger and Melanie Bybee, Glen Rose Medical Center’s Mo Sheldon, Tommy Gibson of GRISD and Luminant/Comanche Peak personnel sat around a big oval table in a room with maps and boards that showed a list of roadblocks.

“It’s all designed to test the organization,” Curtis said.

To further complicate matters, a major accident had occurred on State Highway 144 north of the Mambrino highway intersection. A semi tractor-trailer carrying 8,000 gallons of a liquid and a farm tractor-trailer carrying eight bales of hay had collided and the hay was on fire. Initial reports said the accident was south of Glen Rose, but it was in Hood County.

By 1 p.m. the "disaster" was all over. Officials from the Federal Emergency Management Agency were on hand at each location in the drill taking notes. They will present their recommendations about how to improve response times and reactions.

Meanwhile, all participants said such a drill is invaluable in helping them to understand the complexities of such a scenario — and to be prepared.