TEMPE (3TV/CBS 5) -- Tempe officials say a portion of the damaged Union Pacific Railroad bridge spanning Tempe Town Lake will be demolished Sunday morning. Surrounding homes and businesses will be evacuated as the demolition takes place.
During a press briefing Saturday, Assistant Tempe Fire Chief Andrea Glass said a 150-foot section, the most heavily damaged portion of the bridge on the south end of the structure, will be removed.
One was hospitalized while the other was treated on the scene.
The announcement comes a day after a pair of workers were exposed to hazardous chemicals as they were in the process of cleaning up train cars that had derailed in the accident.
The bridge was damaged after a Union Pacific train derailed and caught fire while crossing a bridge over Tempe Town Lake Wednesday.
"It looks like a scene from hell, truly. A scene from hell," a witness told Arizona's Family. "The flames are intense and the sky is filled with black smoke."
Glass says on Sunday between 7 a.m. and 9 a.m., "small precision cutting charges placed in predesignated and precut locations around a section of the bridge to demolish and remove a small portion of the bridge."
The section is a 150-foot span on the southern end of the the lake between Tempe Town Lake and Rio Salado Road.
PHOTOS: Train fire, bridge collapse over Tempe Town Lake
"It looks like a scene from hell, truly. A scene from hell," a woman who rode her bike under the train bridge merely moments before the collapse and fire told Arizona's Family.