Northern Indiana Public Service Co. (NIPSCO) signed a settlement agreement in which it has agreed to invest approximately 600 million in pollution control technology to resolve violations of the Clean Air Act. The proposed settlement covers all of NIPSCO's coal fired power plants, located in Chesterton, Michigan City, Wheatfield and Gary, Ind. It will require that NIPSCO spend 9.5 million on environmental mitigation projects and pay a civil penalty of 3.5 million. The state of Indiana has been involved with developing this settlement and is a signatory.