The closeness of a measured result for an analysis to a known value for the sample.

Dense, Non-Aqueous Phase Liquids are only slightly soluble and therefore do not readily flush away when spilled into the subsurface. They are also denser than water, which allows them to move under the force of gravity in directions that are often different than the the hydraulically driven prevailing flow of groundwater. Very common and nearly ubiquitous, examples include dry cleaning fluid and metal degreasing compounds.

A remedial action for groundwater that relies upon biodegradation processes taking place naturally within the groundwater to achieve specified remedial objectives, wherein those processes are accelerated by introduction of remedial amendments into the subsurface.

Emerging Contaminants (defined here) are difficult challenges for industrial property owners. The site characterization approaches we apply enable understanding of the origin and extent emerging contaminants with a high level of confidence. Our understanding of their fate and transport characteristics, including the tendency for diffusion into and back-diffusion out of, low-permeability matrix materials within heterogeneous aquifers, supports appropriate remedial decision making.

Actually, most bedrock is fractured. This term is used to denote the special importance of fractures in certain aquifers as the dominant pathways for flow. Most bedrock aquifers in the old, well consolidated rocks that are present in the northeast are dominated by fracture flow. In other areas where rocks are less consolidated and cemented, flow takes place to a larger extent through the inter-granular porosity of the rock matrix itself. Where fracture flow is dominant, understanding the orientation of the fractures becomes very important when attempting to trace areas of impact from source along transport pathways to potential receptors, such as supply wells used by humans or rivers or other ecological resources like wetlands. The borehole geophysical logging services that we offer enable understanding of fracture orientations at the level of accuracy required to make such evaluations.

New Jersey’s Industrial Site Recovery Act (described here) is a law which, along with its predecessor, the Environmental Cleanup Responsibility Act of 1983, insured that risks to human health and the environment associated with legacy discharges at industrial sites are investigated and remediated when industrial operations cease or when industrial property is sold or transferred.

A remedial action, usually for groundwater, that relies exclusively upon ambient, naturally occurring processes to achieve specified remedial objectives, coupled with a monitoring program to confirm and document ongoing effectiveness. Natural attenuation processes take place to some extent at many (perhaps most) sites and for many contaminants. As with any other approach, a decision to apply MNA as a remedy is based upon a completed Remedial Investigation and potentially other (pre-design) studies, which support a conclusion that MNA can be relied upon to achieve remedial objectives.

The first evaluative stage of study conducted as part of the remediation of a site requiring a site-wide evaluation in New Jersey. The PA consists of historical ownership and operations review, interviews, records search, and site inspection aimed at identifying Areas of Concern for which follow-up evaluation and/or sampling are required to assess potential for past Discharges. Such follow-up evaluation and/or sampling takes place during a subsequent stage of remediation known as a Site Investigation.

This class of several thousand substances (described here) include several that have begun to receive regulatory attention, with water quality standards being set hundreds to thousands of times lower than have been traditionally applied for other in organic industrial contaminants. Major game changer that is spurring re-evaluation of some previously remediated sites. Also, different from most other contaminants in that industrial discharges to the air pose risk to soil and groundwater contamination via the atmospheric deposition route. Modern life involves use of many products manufacturing using PFAS including Teflon, floor cleaners and waxes and many other consumer and industrial products. As a result wastewater discharges and landfills tend to be accumulating sources for these constituents. Their global ubiquity complicates efforts to understand their extent on industrial sites where they are used for the purpose of defining appropriate remediation.

A planned series of tasks, typically including inspections, sampling, and analysis, that is intended to evaluate, confirm the effectiveness of, or identify the need for modification of a remedial action.

The closeness of agreement among a series of analyses of the same sample; a measure only of the repeatability of the result, not an indication of Accuracy.

A study stage of RCRA Corrective Action during which evaluations are made, usually including sampling and analysis, to determine whether discharges have taken place at a facility.

An investigation at a site where a discharge has been documented, intended to gather information needed to evaluate remediation alternatives and to support design of a selected remedy. A key component of the RI is defining the Nature and Extent of Contamination. Other important items developed during the RI include understanding of the geologic and hydrogeologic setting, fate and transport of the discharged contaminants, presence of and proximity to any human or ecological Receptors and (in some regulatory contexts), engineering or other design parameters necessary to select and plan a remedial action.

Cylindrical sample of consolidated geologic material, extracted from the sub-surface using drill-rig deployed coring device. Inspected at the time of acquisition to identify rock and aquifer matrix conditions, including fracture patterns. Increasingly, rock cores are collected and sub-sampled to provide material for laboratory analyses to quantify physical and geochemical characteristics and to measure contaminant concentrations in support of contaminant back-diffusion studies.

Cylindrical sample of unconsolidated geologic material, extracted from the sub-surface using a manual or drill-rig deployed coring device. Inspected at the time of acquisition to identify soil and aquifer matrix physical conditions and sub-sampled to provide material for laboratory analyses to quantify physical and geochemical characteristics and to measure contaminant concentrations.

The degree of opacity of a liquid, typically a water sample, resulting from suspended clay and silt, as well as fine inorganic and organic matter, algae, dissolved colored organic compounds, and microscopic organisms. Measured in nephelometric turbidity units (NTU). Rapidly flowing surface waters can be turbulent, maintaining particulate and therefore can exhibit significant natural turbidity. Groundwater typically flows at much slower rates and turbidity of most groundwater is very low. Groundwater samples, usually collected under the stress of pumping, which may disturb and introduce aquifer sediment to the sample, often yield non-representative turbidity results, elevated with respect to actual conditions. The turbidity can interfere with accurate analyses for some laboratory parameters (e.g., biasing results high for metals and potentially for organics, which may sorb to aquifer sediments). Accurately measuring turbidity and obtaining samples exhibiting turbidity that is, as closely as practicable, representative of the ambient (undisturbed) conditions of the sampling matrix, are therefore important concerns during site characterization.

Subsurface Vapor Intrusion occurs when vapor-forming chemicals enter into overlying structures inhabited by people. Volatile vapors usually come from plumes of groundwater contamination.