Scottsdale police said the two workers who died working inside a sewage lift station outside a Scottsdale shopping center on Monday were both from Phoenix.
Jarrod Camp, 41, and Jeremy Johnson, 36, died inside the station in the parking lot of the Promenade shopping center on Frank Lloyd Boulevard and Scottsdale Road.
Scottsdale firefighters said the men weren't wearing protective suits, and were overwhelmed by the high levels of toxic chemicals in the tightly enclosed space.
A third worker, an 18-year-old man, was nearly overcome by sewer gas but managed to climb out and survived.
He was lethargic and covered with sewage when rescuers arrived about 3:45 p.m. and was taken to a Scottsdale hospital for further evaluation.
"He was standing and walking when he came out, but he did look kind of dazed out, out of it," witness Jessica Correa said.
Firefighters in full hazmat suits ventilated the 3 1/2-foot wide and 15-foot deep hole, Scottsdale Fire Division Chief Jay Ducote said. They used a tripod with harnesses to recover the bodies.
The victims were turned over to the Maricopa County Medical Examiner's Office to determine the official cause of death, police said.
All three men worked for Camp Industries, a private sewage maintenance company, and were working on the sewage pumps in the parking lot between the Habit Burger restaurant and Buffalo Wild Wings when two of them called for help.
Ducote said a bystander heard screams coming from the sewer and notified authorities.
The Scottsdale Fire Department said it would investigate why the chemicals inside that sewage line were abnormally high.
"The hazmat materials team had high readings of hydrogen cyanide and hydrogen sulfide," Ducote said. "Hydrogen sulfide is a really bad chemical that is lethal at 250 parts per million, and it was about 200 parts per million with the hazmat teams got out here."
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