Water Quality Outside of Capture Zone Improves with System Operation

Presented on Tuesday, May 6, 2014
Jason R. House, CG, PG1 and Thomas R. Eschner, PG2, (1)Woodard & Curran Inc., Portland, ME, (2)Woodard & Curran, Inc., Portland, ME

A CERCLA site in Central Maine is currently being addressed with source control via containment based on a pump and treat system designed using groundwater modeling of the flow system in fractured bedrock. Appropriately targeted field data collection efforts and monitoring allowed the development of a comprehensive fate and transport model vetted and accepted by State and Federal agencies for use in evaluating plume containment operations. A Technical Impracticability (TI) Evaluation conducted to address whether Source Area Groundwater could be restored to drinking water standards within a reasonable period of time supported the conclusion that a TI Waiver of chemical-specific ARARs would be appropriate for the Source Area portion of the Site.  The final remedy selected for the site included Hydraulic containment of the Source Area Groundwater based on the groundwater flow model and a TI Waiver for the Source Area Groundwater, coupled with continued monitoring of and institutional controls for the Non-Source Area Groundwater. Operational groundwater piezometric monitoring results show strong agreement with model predictions. The data collected to date indicate that capture of the source zone effectively controls migration from the Site. Groundwater quality data from the first Five-Year review since the system became operational suggest that target VOC concentrations in Non-Source Area Groundwater beyond the capture zone are decreasing.


Jason R. House, CG, PG
Woodard & Curran Inc., Portland, ME
Jason House is a Senior Hydrogeologist with experience focused on hazardous waste site investigations and new water supply site investigations utilizing both invasive and non-invasive techniques. His expertise includes all aspects of design, installation, testing, and sampling of groundwater monitoring and pumping wells. Additionally, he has designed, constructed, calibrated, and verified numerous groundwater flow and contaminant transport models that were subsequently employed in hazardous waste investigations and remediation efforts. House is a Certified Geologist in the state of Maine, a Professional Geoscientist in Texas, a Professional Geologist in Pennsylvania, and a Registered Professional Geologist in Georgia.

Thomas R. Eschner, PG
Woodard & Curran, Inc., Portland, ME
Thomas Eschner is a senior project manager with expertise in site characterization and engineering feasibility studies pertaining to groundwater, soil, and surface water and sediment impacts from hazardous waste sites related to both organic and inorganic contamination. He has provided consulting services regarding contamination and remediation of environmental media to state and national governmental agencies and U.S. and international commercial clients. Eschner has participated in regulatory negotiations regarding clean-up levels and scopes of work and has directed investigations related to Remedial Investigations/Feasibility Studies, Remedial Design and Remedial Actions at several Superfund sites.
NGWA may only post those brown bag sessions, Webinars, event sessions, and like for which we have obtained copyright permission from the presenter. Furthermore, by accessing or downloading any of these items, you agree they are for your own personal use and may not be disseminated by any means to others via any medium. Click here to read NGWA's proprietary legend and disclaimers before proceeding.