An explosion at about 7:15 a.m. today at the Carter Lake Filter Plant occurred as workers unloaded chemicals into the plant, officials said.
This afternoon, officials are using a reverse 911 phone system to tell residents to stay home and to keep doors and windows closed. Residents who want to evacuate may do so, but they will not be allowed to return until the area is deemed safe.
A shelter for those who voluntarily evacuate the area or who are not being allowed to return home has been established at the Berthoud Community Center, 248 Welch Ave., according to a Berthoud Fire Protection District spokeswoman.
The Red Cross is helping fill the needs of evacuees at the community center.
A public information line has been established at 962-2079.
Earlier reports speculated that blasting in the area or static electricity ignited the chemicals, one possibly being chlorine.
But information released at about 1:45 p.m. by the Larimer County Emergency Management Office says officials are looking into the possibility that one chemical product was placed into the wrong container, or into a container with a product that reacted with it.
Four plant workers were treated for inhalation injuries. Two were transported to McKee Medical Center in Loveland.
McKee Medical Center spokeswoman Sara Quale said the hospital received two patients from the explosion. They had been decontaminated at the scene, and as of 11 a.m. were still being evaluated in the hospital's Emergency Department.
At the time of the explosion, a blasting operation was taking place nearby with a live charge set for explosives.
A controlled blast to complete static discharge was planned for about 11 a.m., but it apparently was delayed. Officials later said the blast was to occur at about 12:45 p.m.
Authorities used the "reverse 911" system to alert people in the area that the explosion they may hear is not an additional problem at the water plant, according to Larimer County officials.
After the chemical explosion this morning, people in the plant and immediate area were evacuated. Other area residents were advised to stay inside and close windows and doors.
The plant at 7100 W. County Road 8E, on the south side of Carter Lake, is owned by the Central Weld and Little Thompson water districts.
* Three firefighters were entering decontamination at about 9 a.m.
* A 2 p.m. press release from the Colorado State Patrol says the interior of the building was extensively damaged and windows and doors were pushed outward.
* A hazmat crew entered the building at about 2 p.m.
* Larimer County officials say access to the south end of Carter Lake is restricted. That means there is no access to South Shore and Carter Knolls campgrounds, the South Shore boat ramp, or Saddle Bay. Access to the lake from the north is okay, but not past the swim beach. There are no access restrictions to Eagle, Big Thompson, Lowells, and North Pines campgrounds or the North and North Pines boat ramps, the Carter Lake Marina, and the Carter Lake Sail Club. Boating is allowed on all areas of Carter Lake, although ramp access is limited to the north end of the lake.
