Hudson River Dredging Water

Phase 1 Far-Field Water Quality Monitoring (Resuspension)

The monitoring data on this page reflects performance standard monitoring collected during Phase 1 dredging. Phase 1 dredging occurred from May 15, 2009 to October 26, 2009 and the data was collected from May 2009 to December 2009. EPA issued performance standards for Phase 2 dredging based on the knowledge gained during Phase 1 and input from the peer review panel. To return to viewing Phase 2 performance standard monitoring Click Here.

Legend

PCB concentrations in parts per trillion (ppt)

Typical Operations: Far-field PCB concentration is less than the control level (350 ppt) and the standard (500 ppt)

Control Level: Far-field PCB concentration is between 350 ppt and 500 ppt. Additionally, the seven day running average is above 350 ppt.

Exceedance Level: Far-field PCB concentration exceeds the standard (confirmed occurrence)

Phase 1 Weekly Calendar (Please click on data for more information)
Phase 1 dredging occurred between May 15 - Oct 26, 2009. Performance standard monitoring data was collected daily between May-Dec 2009. Once all Phase 1 river activities were completed, and baseline (pre-dredging) water PCB levels were reached, weekly monitoring began (December 28, 2009). Baseline monitoring results are received in accordance with standard lab turnaround time (approx. 21 days).

Phase 1 Calendar

	Rogers Island	Thompson Island	Thompson Island (additional results)	Schuylerville (Lock 5)	Schuylerville (Lock 5) (additional results)	Stillwater	Waterford	Albany	Poughkeepsie
Apr 24	-	-	-	-	-	-	-	-	-
Apr 25	-	31(24 hr Composite Sample) Data may not be representative due to high flows. Data under evaluation.	-	18(24 hr Composite Sample) Data may not be representative due to high flows. Data under evaluation.	-	-	12(24 hr Composite Sample) Data may not be representative due to high flows. Data under evaluation.	-	-
Apr 26	-	-	-	-	-	-	-	-	-
Apr 27	-	-	-	-	-	-	-	-	-
Apr 28	-	-	-	-	-	-	-	-	-
Apr 29	-	-	-	-	-	-	-	-	-
Apr 30	-	-	-	-	-	-	-	-	-

Phase 1 Dredging Monitoring Schedule
Routine Monitoring is performed during typical operations, and Contingency Monitoring is performed when the Control Levels are exceeded.

Sampling Frequency	Rogers Island	Thompson Island	Schuylerville (Lock 5)	Stillwater	Waterford	Albany	Poughkeepsie
Routine	Weekly	Daily	Daily	Weekly	Daily	Monthly	Monthly
Contingency	Daily	Twice Daily	Twice Daily	-	-	Weekly	Weekly

Phase 1 Baseline Monitoring Schedule

Sampling Frequency	Rogers Island	Thompson Island	Schuylerville (Lock 5)	Stillwater	Waterford	Albany	Poughkeepsie
Baseline	Monthly	Weekly	Weekly	-	Weekly	Monthly	Monthly

Engineering Performance Standards: Resuspension

Strict Engineering Performance Standards have been developed to minimize resuspension of PCBs during dredging to limit the transport of PCBs and protect water intakes.

What is the Phase 1 Standard?

The performance standard for dredging resuspension sets a resuspension level of 500 parts per trillion (ppt) Total PCBs – the EPA drinking water standard under the Safe Drinking Water Act.

How is the Phase 1 Standard Measured?

Through an extensive river water quality monitoring program at upstream, “near-field” and “far-field” stations.

near-field: within 300 meters downstream of dredge (turbidity, total suspended solids and metals)
far-field: greater than 1 mile downstream (total suspended solids, metals and PCBs)
(see Far Field Water Monitoring Locations map at left)

Click here to view Phase 2 Monitoring