Update for the Week Ending February 19, 2016

Site Remediation Continues

On-going activities:

  • Continued the application of water and calcium chloride for dust control;
  • Continued the application of odor-suppressant foam and BioSolve for dust and odor control;
  • Maintained erosion and sediment (E&S) controls (Installed waddles - wood chip filled fabric tubes - around the Site perimeter to prevent silt and sediment from leaving the Site and covered all stockpiles);
  • Continued operation of the WTP;
  • Continued the Bucket Soil Mixing (BSM) demonstration test in the Holder No. 2 tank beneath the temporary containment building (TCB); and
  • Initiated pre-trenching and demolition of subsurface obstructions in the alignment of the Support of Excavation (SOE) wall.

Recently completed activities:

  • Completed the removal of asphalt along the SOE wall alignment in preparation for pre-trenching.

Upcoming activities:

  • Conduct full scale BSM in the Holder No. 2 tank;
  • Continue the shipment of impacted shallow soils for treatment and disposal;
  • Ship removed asphalt for recycling;
  • Decommission former monitoring wells on Site;
  • Pre-drill for deep obstruction removal along the SOE wall alignment;
  • Crush clean, reusable concrete for use as backfill in the deep excavation;
  • Install electrical service from Con Edison and demobilize the temporary generator from the Site; and
  • Install dewatering wells and initiate ground water extraction.

Community Air Monitoring Plan Summary

Community air monitoring, initiated on Tuesday, December 1, 2015, continues as intrusive (ground disturbance) activities are conducted.

There were no fifteen-minute Action Limit exceedances of Total Volatile Organic (TVOCs) or odors during this reporting period.

There was one instance of the fifteen-minute average concentration of Particulate Matter (PM-10) [dust] exceeding the applicable Action Limit on February 15, 2016, attributable to offloading a delivery of cement to the storage silo at the on Site grout plant.  Following the offloading, dust levels returned to below the Response Limit.  A shield will be installed over the silo relief port, and a water atomizing mister will be utilized to mitigate dust from the grout plant operations.

There was one instance of the fifteen-minute average concentration of PM-10 [dust] and one instance of odor exceeding the applicable Action Limit on February 18, 2016, attributable to pre-trenching activities.  Work was stopped, and water (with BioSolve) and odor suppressant foam were applied to the pre-trenching area until dust and odor levels returned to below the Response and Action Limits, respectively.

If you have any questions or comments about the work on the Site, please use the Williamsburg MGP Telephone Hotline at (718) 403-3053.

Photos of Activity

Removing asphalt along the SOE wall alignment in preparation for pre-trenching

Removing asphalt along the SOE wall alignment in preparation for pre-trenching

Initiating pretrenching along the SOE wall aligment and applying water with BioSolve for dust and odor control

Pre-trenching along the SOE wall alignment and applying odor suppressant foam for dust and odor control

Pumping water from the Holder No. 2 tank for transfer to the water treatment plant prior to conducting bucket soil mixing

Conducting the bucket soil mixing demonstration test in the Holder No, 2 tank beneath the temporary containment building

Covering the reuse soil stockpile with heavy duty tarps for dust control