A long-term response action to address chlorinated volatile organic compounds in bedrock groundwater.

Since 2020, Nobis has been contracted to EPA Region 3 (ESO TO 68HE0320F0031) with team subcontractor support from GES to perform operation, monitoring and maintenance (OM&M) of the groundwater extraction treatment system (GETS) for Plume 1 and enhanced in situ bioremediation of Plume 2 to support long-term response action (LTRA) at the Ordnance Products, Inc., Superfund Site in North East, Maryland, to address chlorinated volatile organic compounds (CVOCs) in bedrock groundwater.

The team responds to system alarms and/or emergency shutdowns either remotely or in-person as needed in addition to scheduled bi-monthly OM&M visits. The operator collects bi-monthly treatment system data, including instantaneous and average flow rates, flow volume, estimated run time (days), and estimated percentage run time. The project engineer monitors system performance and provides recommendations to the operator for system operational improvements as needed. The GETS operates with uptime performance greater than 85%. A report is prepared and submitted to EPA within 30 days from the end of each month for the month prior.

In addition to routine OM&M of the GETS, field activities performed for this project by Nobis with GES have included: a comprehensive monitoring well inventory and survey effort which integrated multiple historical sources of information; surface water sampling and site visit support for Five-Year Reviews; semi-annual groundwater sampling (low-flow and volumetric methodologies); vegetation removal; and upgrades to the treatment system building and site security.

Currently implementing select recommendations from a recent optimization review completed by EPA in addition to optimization recommendations developed by the project team to increase GETS efficiency and fill a data gap relative to the off-site portion of Plume 1, including: drilling and installation of two new extractions wells (one in the shallow aquifer less than 100 feet below ground surface [bgs] and one for the deep aquifer up to 200 feet bgs) with connection to the GETS; 72-hour pump tests (for both new extraction wells); replacement of the air stripper and all associated components to accommodate the anticipated increase in flow; underground piping jetting; and, pilot testing an iron sequestering agent. All intrusive field work is performed using anomaly avoidance techniques with construction support provided by qualified Unexploded Ordnance Technicians.

challenges

  • Due to the contract between EPA and the incumbent expiring before award of the current contract to the Nobis Team in 2020, a project transfer with the previous contractor did not occur. As a result, we were required to assume operation of the GETS without any assistance from the incumbent.
  • Between February and April 2026, implemented a change in scope on short notice to increase staffing for OM&M from two days per month to two days per week to support a transition between EPA and the State of Maryland for OM&M responsibilities.