Oak Ridge National Laboratory announced Tuesday that they're cutting 350 jobs by the end of the calendar year.

In a letter sent to employees, ORNL Director Thomas Zacharia said the reductions will be made primarily among staff who charge to indirect accounts, along with some research staff affected by fiscal year 2017 funding who could not be placed elsewhere in the lab.

Zacharia replaced 10-year director Thom Mason on July 1. Mason's departure was announced in February.

"By reducing these positions, ORNL will be able to maintain competitive chargeout rates while freeing resources for discretionary investments that will modernize Lab infrastructure and maintain core research capabilities in the mission areas assigned to ORNL," Zacharia said.

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A Self-Select Voluntary Separation Program, or VSP, will start on Aug. 14. According to the letter, employees can apply from Aug. 14 to Sept. 27. Accepted employees will leave the payroll by Dec. 31.

Meetings will take place this week to explain details on the VSP.

"We are hopeful that the VSP will provide for all necessary staff reductions. If more are needed, an Involuntary Separation Plan (ISP) will be implemented," Zacharia said.