By secondary treatment, the COD, NH4(superscript +)-N, SS and chroma of the landfill leachate can not meet the requirements of the national discharge standard.

• 摘要北京市某垃圾填埋场渗沥液经二级处理后，其出水中COD、NH4(上标+)-N、SS和色度等主要污染物质仍不能达标排放。