This final rule represents the culmination of the Agency's effort to develop Clean Water Act (CWA) national effluent limitations guidelines and pretreatment standards for wastewater discharges from certain landfills. The final regulation establishes technology-based effluent limitations for wastewater discharges associated with the operation and maintenance of new and existing hazardous and non- hazardous landfill facilities regulated, respectively, under Subtitle C and Subtitle D of the Resource Conservation and Recovery Act (RCRA). Sources of landfill wastewater include, but are not limited to, landfill leachate and gas collection condensate. Today's final rule does not establish pretreatment standards for the introduction of pollutants into Publicly Owned Treatment Works (POTW) from the operation of new and existing landfills regulated under Subtitle C or Subtitle D of RCRA. The rule does not apply to wastewater discharges from "captive" landfills--those landfills associated with other industrial or commercial activities, in most circumstances. For example, it does not apply to captive landfills that only receive wastes generated by the industrial operation directly associated with the landfill. In addition, the rule does not apply to captive landfills that receive both wastes generated by the industrial operation directly associated with the landfill as well as other wastes, so long as the other wastes are similar in nature to the wastes generated by the industrial operation directly associated with the landfill. Further, the regulation does not apply to wastewater discharges associated with treatment of contaminated ground water from hazardous and non-hazardous landfills. The final effluent limitations guidelines will benefit the environment by removing 900,000 pounds of pollutants per year at an estimated annualized cost of $7.6 million.