Robert Olson

Robert Olson's booking mug

During the time Robert Olson worked as a senior wastewater plant operator for the city of Avondale, there was never anything outstanding or unusual in his short employment history there, a city spokeswoman said.

But during the three years Olson worked the same job for the city of Mesa, the economic situation worsened and so did Olson’s frame of mind, according to court documents.

Olson, 43, of Gilbert, took the job at Mesa’s Deerfield Wastewater Treatment Plant at 4400 S. Greenfield Road in Gilbert so he could be closer to his home and spend more time with his family, according to the resignation letter he submitted to the city of Avondale. But after all Mesa city workers were required to take a 2 percent pay cut about two years later, with wages remaining frozen today, he gradually became angry at health-care premiums and city spending — including a new spring training facility for the Chicago Cubs, according to Maricopa County Superior Court documents.

And about two years ago, Olson lost his home in east Mesa’s Mesquite Canyon neighborhood to foreclosure and his family moved in with his in-laws, according to one of his former neighbors.

Now, Maricopa County prosecutors are reviewing an intentional act of terrorism case against Olson, who was arrested after a two-hour standoff with the Gilbert police SWAT team Friday morning. Olson had called 911 about 2:30 a.m. to report that he had shut off numerous operating control systems inside the plant’s 14-building facility that caused a buildup of methane gas, according to Gilbert police. Armed with a handgun and knives, Olson was the lone worker inside the plant during the midnight shift and although safety mechanisms kicked in at the plant that would’ve released any excess methane gas into the atmosphere, police say Olson’s actions endangered the lives of first responders and believe he was under the influence of either alcohol or drugs, according to court records. After he retreated to the top of one of the plant buildings prior to the standoff, he told police that a “muzzle flash” from their weapons could cause the building to ignite.

He also told authorities he wanted to show the city that “employees had power,” and that the plant could blow up, the report stated.

Olson, who police believe was “mentally disturbed” according to the report, now is being held in Maricopa County’s Fourth Avenue jail on a $250,000 bond and also faces charges of criminal damage, tampering and criminal harassment.

Gilbert police submitted the case against Olson to the Maricopa County Attorney’s Office on Monday and prosecutors are trying to determine whether and how Olson will be charged.

John McCaffery, a former neighbor of Olson’s in Mesa for about 10 years, told the Tribune he saw news reports of the incident about the wastewater treatment plant being shut down, but did not realize Olson was involved.

“Omigosh,” McCaffery said. “He’s a heckuva a nice guy. I knew he was struggling with his house that went into foreclosure and moved his family in with his in-laws, but I didn’t realize he was having other problems. He was such an easy-going guy, and didn’t have trouble with any of the neighbors. I can’t picture Rob doing anything like that. I hope he’s not in too much trouble.”

It’s not yet clear whether Mesa will revise any specific safety measures for the water treatment plant, which supplies water to nearby golf courses and is used to help irrigate crops, according to information from Mesa.

“Cities are constantly re-evaluating safety practices and where there is room to improve, which is more of a practice than just being done because of an incident” said Steven Wright, a Mesa city spokesman. “Whether this will trigger something, we don’t know because it’s still early on in the investigation.”

The plant is operated by Mesa, but serves parts of Mesa, Gilbert and Queen Creek.

Olson is a U.S. Army veteran from 1986-89 who was certified to work as a wastewater plant operator by the Department of Environmental Services, and passed his FBI background checks at each city he worked for, according to information from Mesa.

Olson also worked for the city of Phoenix in a similar capacity for a time after first working for Mesa a number of years ago, according to authorities. However, no one from Phoenix responded to inquiries from the Tribune regarding his employment history.

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