MONTPELIER, Vt. – Six elderly Massachusetts women are scheduled to go on trial next week on charges they chained themselves to the gate at the Vermont Yankee nuclear power plant two days after the state was hammered by the remnants of Hurricane Irene.

The women, all members of the Shut It Down Affinity Group, traveled to the plant gate in Vernon on Aug. 30, 2011, used a chain and padlock to lock the entrance gate and chained themselves to the fence.

It was one of about 22 protests the group has mounted against the reactor’s continued operation in recent years. There have been five similar protests since the one that triggered the trespass charges on which the women are to be tried next week.

The six were identified as Frances Crowe, 93; Nancy First, 82; and Patricia “Paki” Wieland, 68, all of Northampton; Hattie Nestel, 73, of Athol; Ellen Graves, 69, of West Springfield; and Mary Kehler, also known as Betsey Corner, 64, of Colrain.

Neither Windham County State’s Attorney Tracy Kelly Shriver, nor her deputy, Steven Brown, who is handling the case, would say why that particular protest was selected from nearly two dozen similar events in recent years as the one that would produce charges.

“Historically the Windham County state’s attorney’s office has not filed charges against Vermont Yankee protesters,” Shriver said.

Each defendant faces a potential penalty of three months in jail and a $500 fine.