UMATILLA – Staff at the Two Rivers Correctional Institution are calling for changes in the management of prisoners there after two assaults by inmates on security officers within a two-month period.

The assaults took place after the state Department of Corrections changed the way some inmates are managed at the prison. Since October, prisoners who had just been moved out of the high security lock-down unit were being housed together in one section of the prison before being reintegrated into the general prison population. Before the change, high-risk inmates had been distributed throughout the prison. Security staff fear they are more vulnerable to attack because the institution’s most dangerous inmates are now concentrated in one unit, said David Neilson, a spokesman for AFSCME, the union that represents workers at Two Rivers.

“The stress level is immense,” Neilson said. “We’re getting to the point where we feel we need to make some changes or someone’s really going to get hurt, or killed.”

The first assault in the close-supervision unit took place Dec. 26, when an officer was jumped by two inmates and beaten, suffering a broken nose, concussion and severe short-term memory loss. He spent several days in the hospital, but has returned to work. The second assault took place Feb. 22, when another officer was attacked by an inmate with a homemade knife who slashed his face, leaving a two-inch cut. That officer was treated and released from the hospital the same day.

TRCI Superintendent Robert Schiedler said managers met last week to discuss the problem and identify what can be done to reduce the risk of attacks by inmates on security officers.

“We don’t want staff to keep getting injured by inmates,” he said.

Neilson said security officers want the prison to return to its old way of managing dangerous inmates by distributing them in different units. He said the union has been talking with local legislators about its concerns, and hopes to meet with Rep. Bob Jenson, R-Pendleton, who has been invited to tour the prison and talk to staff.

TRCI houses 1,450 inmates, 45 of which are being held in the close-supervision unit where they are evaluated before being approved for release into the general prison population. The close-supervision unit can house a maximum of 76 inmates. The institution’s staff includes 269 security officers.