G4S Security Lockout Ends @ Xcel Monticello Nuclear Plant After a Show of Solidarity By Labor Unions. https://www.nunso.org/ <br /> <br />Nuclear Security Officers have been picketing this week outside Xcel Energy’s nuclear power plant in Monticello in an ongoing labor dispute that started on August 31, 2019 <br />The 23 union employees work for G4S, a London-based company under contract with Xcel to provide security for the plant. <br /> <br />G4S locked the workers out after their contract expired and they rejected a proposed new contract. The union said the company wants to change the employees’ health plan, which it said would result in higher costs and less coverage for workers.