GILBERT, Ariz. --
Gilbert Police said this was no April Fool's joke but rather an act of domestic terrorism.
A city of Mesa Water Resources employee is charged with terrorism and making terrorist threats after he turned off numerous waste water treatment operating systems at a facility overnight, Gilbert Police said.
The Greenfield Water Reclamation Plant near Greenfield and Queen Creek Roads is a massive facility. Fourteen buildings on the campus transform sewage from Gilbert, Mesa, and Queen Creek into water suitable for irrigation.
Authorities said 43-year-old Robert Olson was the sole treatment plant operator working the midnight shift Friday. Armed with a handgun, he walked through the facility alone, methodically turning off major operating systems at the plant.
Olson is certified through the Arizona Dept. of Environmental Quality as a waste water treatment operator. Left untreated, the sewage in the system would cause a buildup of methane gas, which could cause a huge explosion.
City workers were emphatic that the public not be alarmed. They said nobody was harmed, and the safety mechanisms in the plant worked as expected.
For an unknown reason, Olson called 911 about 2:40 a.m. Friday, almost three hours after they say he had begun to sabotage the utility. SWAT officers negotiated with him for two hours before arrested him. Police said he had a gun on him when they took him into custody.
During the two-hour standoff, SWAT officers escorted waste water employees through the campus, restarting the major systems.
Olson has worked for Mesa's water resources department since 2007. According to neighbors, Olson is married with two young children. Neighbors said they lost their house in Mesa two years ago to foreclosure.
Dave Melgoza lived next door to Olson since 1999. He said he never knew of any mental instability.
"He wasn't a gun toting radical by no means," said Meldoza. "Robert was never malicious or anything like that. He was a great guy all around. I'm shocked."
Police said he's being booked into Maricopa County's jail in downtown Phoenix.
Police have not released a possible motive.
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