瀚霖物流:求人帮我翻译

Congress listed 27 pollution sources in the FWPCA for which the EPA was required to
develop performance standards. The EPA was also given the authority to add to this list;

40 sources subsequently were identified in the NPDES Primary Industry Categories
list.19 The EPA is required to periodically review new source requirements and make
amendments reflecting changes in technology and economic conditions.

The system for controlling effluent from public wastewater treatment plants (called
publicly owned treatment works, or POTWs) differs slightly from that of other dis-
chargers. POTWs must meet effluent standards characterized by waste receiving "sec-
ondary treatment." EPA initially defined secondary treatment to effectively limit com-
pliance to communities using activated sludge technology meeting rigorous
performance standards. This requirement was subsequently viewed as excessive in
many situations, particularly where small POTWs were discharging into waters capable
of rapidly assimilating the wastewater. Moreover, it was viewed as economically
impractical and ecologically unnecessary for many small communities. Therefore,
these requirements were modified.