Far-Field Water Quality Monitoring (Resuspension)

Phase 2 Year 4 dredging occurred between May 7 and November, 2014. Backfilling will continue into December 2014. Performance standard monitoring data is collected daily during the dredging season. The locations of the water monitors are shown on the Far-Field Water Monitoring Locations map at left. View water quality data on the Water Quality Interactive Data Map. Phase 2 dredging operations will resume in spring 2015.

Phase 1 data is available by clicking on the link at the bottom of the page.

Weekly Calendar (Please click on data for more information)

Week of Monitoring: (click on date for different week) View Most Recent Data
Rogers IslandThompson Island Thompson Island (additional results)Schuylerville (Lock 5)Schuylerville (Lock 5) (additional results)StillwaterWaterfordTroyAlbanyPoughkeepsie
Nov 23----------
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Legend:

PCB concentrations in parts per trillion (ppt).

Typical Operations: Far-field PCB concentration is less than the control level (500 ppt Total PCBs).

Control Level: Far-field PCB concentration is greater than 500 ppt Total PCBs. 

Exceedance Level: Far-field PCB concentration has a confirmed exceedance of 500 ppt Total PCBs.


Phase 2 Dredging Monitoring Schedule
Routine Monitoring is performed during typical operations.

In-Season

Sampling FrequencyRogers IslandThompson IslandSchuylerville
(Lock 5)
StillwaterWaterfordTroyAlbanyPoughkeepsie
Routine Monthly As Needed Daily As Needed As Needed Daily Monthly Monthly

 

Off-Season

Sampling FrequencyRogers IslandThompson IslandSchuylerville
(Lock 5)
StillwaterWaterfordTroyAlbanyPoughkeepsie
Off-Season Monthly N/A Weekly N/A Weekly N/A Monthly Monthly

 

Engineering Performance Standards: Resuspension

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 Standard?

The Resuspension Standard for Phase 2 dredging is the control level of 500 parts per trillion (ppt) Total PCBs, the EPA drinking water standard under the Safe Drinking Water Act.  If there is a single exceedance of the Resuspension Standard at one of the monitoring stations located a mile or more downstream of dredging operations, EPA may require GE to conduct evaluations of the dredge operations and/or implement best management practices.

If the 500 ppt Total PCBs standard is exceeded at the first far-field station that is at least one mile or more downstream from dredging operations (currently Schuylerville [Lock 5]) for five days out of any seven-day period or there is a confirmed exceedance at Waterford/Troy, EPA may require GE to slow down or shut down dredging operations upstream. If a slowdown or shutdown is required, normal operations will typically resume when the concentration at the applicable monitoring station is below 500 ppt Total PCBs for two consecutive days.

EPA will use an adaptive management approach to make adjustments to dredging operations and the application of the performance standards, as necessary, as Phase 2 progresses to ensure that cleanup goals are met.

How is the Standard Measured?

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

  • Near-field: 300 meters downstream of dredging (PCBs and total suspended solids)
  • Far-field: greater than one mile downstream of dredging (PCBs and total suspended solids) (see Far-field Water Monitoring Locations map at left)

 

View Phase 1 Monitoring