TRENDS IN REDUCTION OF TOXIC POLLUTANTS

摘要

In 1993, the 103rd United States Congress legislated the Government Performancernand Results Act (GPRA) which requires the United States Environmental ProtectionrnAgency (USEPA) to measure performance of its various programs, and reportrnaccomplishments annually to the President and the Congress. In the spirit of GPRA, arnstudy was conducted to determine the reduction of industrial toxic pollutantsrndischarged to publicly owned treatment works (POTWs), and subsequently to landrnthrough application of biosolids.rnThis paper presents a snapshot of national, regional, and local trends in the massrntransfer of toxic pollutants to POTWs, the metals quality of biosolids generated byrnPOTWs, describes the limitations of data obtained from Toxic Release Inventoryrn(TRI), Region 5 (PCS), and from three different POTWs.rnThe results show that the national, regional, local trends in the transfer of toxicrnpollutants to POTWs exhibit a continuous and consistent reduction. The reduction inrnTRI metals, cyanide, and regulated TTOs transferred to POTWs is about 80%. Thernregion 5 TRI trend for other non-regulated organics transferred to POTWs was 24%.rnThis value is relatively lower than the national TRI value. In terms of metals quality ofrnbiosolids, Part 503 regulated metals show significant reduction in land appliedrnbiosolids. The reduction in emissions of volatile organic compounds (VOCs) from sixrnof the seven water reclamation plants (WRPs) of the Metropolitan Water ReclamationrnDistrict of Greater Chicago (MWRDGC) varied between 10 and 75%. The actualrnannual emissions were in the range of 0.05 to 6.58 tons/year in1997, indicating thatrnnone of the WRPs is a "major source" of VOC emissions.