RIVERSIDE (CBSLA) – Amtrak is set to close a major call center in Riverside which employs about 550 people.

In an email sent to workers Wednesday, Amtrak announced it was closing the Riverside reservation center. The closure will take effect Jan. 18.

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Tim Griffin, Amtrak chief market officer, wrote in the email that the closure was due to the fact that 90 percent of Amtrak customers now book reservations online.

“At our busiest time, only 25 percent of our agents are on the phone at the same time,” Griffin wrote in an email which was obtained by the Press-Enterprise.

The call center’s operations will be consolidated with a call center in Philadelphia and the Riverside property will be sold.

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Amtrak spokesperson Olivia Irwin told CBS2 that 31 management positions are being eliminated as part of the closure. All other Riverside center union employees who want to relocate to the Philadelphia facility will be able to do so “with the same pay and benefits,” Irwin wrote.

The managers will have the option of either accepting severance packages or moving into union positions.

“From an operational efficiency and cash perspective, it is better to have many people at one location than smaller groups of people at multiple locations,” Griffin wrote.

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However, union leaders told the Press-Enterprise that they believe Amtrak is contracting with a third-party company in Florida, whose employees are being paid around minimum wage.