ARCHIVE SITE - Last updated Jan. 19, 2017. Please visit www.NACWA.org for the latest NACWA information.
ARCHIVE SITE - Last updated Jan. 19, 2017. Please visit www.NACWA.org for the latest NACWA information.
Over the past few years, several wastewater utilities have experienced elevated pollutant concentrations in their biosolids resulting from the release of legacy pollutants during sewer system cleaning projects. In some cases, the elevated concentrations adversely affected the management of the biosolids end-product. As clean water agencies continue their work to rehab and clean their existing collection and interceptor systems, this scenario may become more common. This Regulatory Alert is intended to ensure the NACWA membership is aware of this potential problem and to provide insight on preventative measures that some agencies are taking. For more information, contact Chris Hornback, NACWA at 202/833-9106 or This e-mail address is being protected from spambots. You need JavaScript enabled to view it . NACWA Members Cautioned to Evaluate Cleaning Project Impacts on BiosolidsNACWA is aware of two specific instances where sewer cleaning operations have been linked to elevated biosolids pollutant concentrations – one involving mercury and the other polychlorinated biphenyls (PCBs). Pollutants such as mercury are especially prone to accumulation in grit and solids in the collection system and may be re-suspended during cleaning operations. While PCB production in the United States ended in the 1970s, their widespread use prior to the ban often resulted in the settling of solids with elevated PCB concentrations in the older portions of many collection systems. The two brief case studies below are only intended to raise awareness of the potential issue for the NACWA membership.
If you or your agency has additional information that may provide added insight for the NACWA membership on this issue, or if you would like additional information on either of these case studies, please contact Chris Hornback, NACWA at 202/833-9106 or chornback@nacwa.org. |