A.29 Hudson River, NY

A.29.1 Summary

Environment:	Freshwater
Contaminants of Concern:	PCBs: hotspots were 50 ppm or greater
Final Remedy:	Cofferdams and sheet piling was used to dewater some of the sediment throughout the river. Contaminated sediment was taken to multiple off-site facilities (Michigan, Texas, and Idaho).

A.29.2 Site Description

Year: 2009-present

Water depth: 0–25 ft

Target volume: 2.4 million yd³

Actual volume removed (as of 2011): 660,000 yd³ 

Contaminated sediment area: 43 miles

A.29.3 Remedial Objectives

Remove substantial amount of PCBs in river.

A.29.4 Remedial Approach

A mechanical dredge with an environmental bucket was used. The area was divided into 8 pools by 8 dams and locks. Forty hotspots are most closely being investigated.

A.29.5 Monitoring

The SWDA standard of 500 ppt used and was exceeded 3 times. Temporary shutdowns when suspension levels were too high. Silt curtains were implemented and dredging continued.

RAOs/project objectives achieved? Dredging was slowed due to logging debris in river. There is currently ongoing dredging at this site. "Spoils" sites have been covered with low permeability1) Characteristic of a material or membrane that allows liquids or gases to pass through it; 2) The rate of flow of a liquid or gas through a porous material. soil caps, with 150,000 tons of cover used for backfill and caps.

A.29.6 References

Cashman. http://www.jaycashman.com/project-details.php?ID=199.

The Hudson River Dredging Project. Dredging of the Hudson River Chronology. http://www.hudsondredging.com/dredging-of-the-hudson-river-chronology/.

EPA Hudson River PCBs Superfund Site Dredging Data Website. http://www.hudsondredgingdata.com/

U.S. EPA. First Five-Year Review Report for Hudson River PCBs Superfund Site. June 2012. http://www.hudsondredgingdata.com/documents/pdf/Hudson-River-First-FYR.pdf.

Major Contaminated Sediment Sites Database; Sept. 2004 as updated 2008. http://www.smwg.org/MCSS_Database/MCSS_Database_Docs.html.

Publication Date: August 2014