Improving the Conceptual Site Model with Mass Flux and Mass Discharge Calculations
Presented on Monday, April 29, 2013
Chris Gurr1, Heather Hallett, P.G.2 and Kim Kaster1, (1)CDM Smith, New York, NY, (2)CDM Smith, Latham, NY
Chlorinated ethenes and minerals spirits were released from underground storage tanks at a former paint factory north of New York City. The release was first noticed when an oily sheen was observed seeping into a river 300 feet downgradient of the factory in the 1990s. CDM Smith conducted a remedial investigation and feasibility study at the site. A key element of the remedial investigation was development of a robust conceptual site model (CSM) to support development of remedial alternatives in the feasibility study.
Due to the presence of a commuter railroad located between the facility and the river, groundwater characterization was limited to two transects of monitoring wells—one along the building and another along the river bank. Despite these limitations, the monitoring well configuration was sufficient to calculate mass discharge and mass flux of contaminants between the two transects. The calculations were used to clarify the CSM in three ways: bound the uncertainty of contaminant mass under the railroad tracks, estimate the fate of contaminants in the plume between the source and the river, and estimate the mass of contaminants discharging to the river.
This presentation will discuss the design of the monitoring well transects at the source and the river bank, and the mass flux and mass discharge calculation methodology. The results and associated uncertainty of the analysis will be interpreted, focusing on how the results informed the CSM. The presentation will conclude with a discussion of how mass flux and mass discharge can be useful for the development of measurable and achievable remedial action objectives.
Chris Gurr
CDM Smith, New York, NY
Mr. Gurr is an environmental engineer with expertise in contaminant fate and transport, sediments, remediation technology, and GIS. He is actively involved in site investigation and remediation work at New York State and federal Superfund sites in New York and New Jersey.
Heather Hallett, P.G.
CDM Smith, Latham, NY
Heather Hallett is a hydrogeologist and project manager with CDM Smith in Albany, New York. Her areas of expertise include remedial investigations, contaminant fate and transport, and hydrogeology. She has a BS in geology from Binghamton University and a MS in hydrology from New Mexico Tech.
Kim Kaster
CDM Smith, New York, NY
Kimberly Kaster is an environmental engineer with CDM Smith in New York City. She is an active member of CDM Smith project teams for remedial investigations and designs for contaminated sites in New York, New Jersey, and Puerto Rico. Her interests include remedial technologies, fate and transport, and groundwater contamination. She has a Bachelor of Science in Environmental Engineering Science from the Massachusetts Institute of Technology.
