After a strike and lockout that has lasted a month, Pilgrim Nuclear Plant workers were holding a day-long vote Sunday on a tentative agreement with plant owner, Entergy Corp.
The Utility Workers Union of America Local 369 said the picketing would continue as the voting took place.
The bargaining committee had endorsed the proposal and recommended ratification.
Details of the tentative agreement, reached Friday, have not been disclosed.
At issue were concerns about healthcare, staffing levels, and pay.
Union members had rejected an initial agreement.