Forensic Evaluation

Arranger Allocation for Radionuclides Contamination

Adam H. Love, Ph.D.


A Superfund site in Pennsylvania has extensive and varied radionuclide contamination. The former site owner/operator has limited funds available to pay for site investigation and clean-up, and the Department of Justice (DOJ) needed to determine what share of the site liability could be expected to be allocated to other PRPs that sent radionuclide-containing products to this site for disposal. The Department of Justice recognized that this evaluation was especially difficult as a result of the complex operational history, limited historical records, variety of radionuclides wastes involved, and multi-component proposed remedy.


Roux provided a detailed reconstruction of the arranger potential contributions to site contamination through:

  1. Evaluation of the waste handling and disposal practices at the site.
  2. Evaluation of radionuclide handling from normal facility operations.
  3. Development of a database detailing the amount of radionuclide activity sent to the facility from each arranger.
  4. Assessment of the specific radionuclides and radionuclide form associated with each arranger.
  5. Evaluation of the fate and transport of radionuclides from locations of normal facility handling locations and location of waste handling and disposal.
  6. Assessment of radionuclide contributions to Operable Units and the drivers for the proposed remedies.

Roux provided the Department of Justice an overall assessment of the contribution-based allocation of arranger liability for each of the PRPs receiving 104(e) letters from US EPA. The arranger liability allocation methodology and basis received praise from DOJ, its recommendations were adopted by DOJ, and DOJ sent the recommendations to US EPA for approval.

Evaluation of Historical Sudden and Accidental Petroleum Releases

Adam H. Love, Ph.D.


Remediation of the location where a former petroleum transfer corridor was operated for approximately 80 years resulted in over $100M in cleanup costs. The responsible party sought coverage from their insurance carriers based on the allegation that the contamination and subsequent remediation was substantially the result of sudden and accidental releases of crude oil, diesel, and gasoline from the petroleum operations. The group of insurance carriers needed an expert to evaluate the quantity and location of contamination that was associated with the alleged sudden ad accidental releases in order to provide a technical basis for their coverage.


Roux defended the joint defense group of insurance carriers against a suit seeking coverage for all remediation costs. Roux used multiple lines of evidence to demonstrate that all of the site contamination could not have resulted from the alleged sudden and accidental releases. Roux was able to conclude that:

  1. There was an extensive history of documented petroleum releases resulting from typical operations.
  2. The remediated petroleum hydrocarbon contamination was not chemically fingerprinted or age dated objectively to specifically attribute the contamination to alleged sudden and accidental release over releases from typical operations.
  3. The geographic extent and depth of remediated contamination were inconsistent with the expected fate and transport of the alleged sudden and accidental releases.
  4. The volumes of remediated petroleum hydrocarbon contamination were inconsistent with descriptions of the alleged sudden and accidental releases.
  5. The amount of degradation that in the remediated petroleum hydrocarbon contamination was inconsistent with the timing of the alleged sudden and accidental releases.

The Roux Expert was deposed on these opinions with needing to modify any opinions. Matter settled on highly favorable terms for each of the carriers.

Highway Fueling Stations

Neil M. Ram, Ph.D., LSP, CHMM

New Jersey

Roux was retained by a major oil company to evaluate the timing of releases at four service stations. Roux utilized a number of forensic tools to identify the approximate date of release at each of the four facilities. These tools included: evaluation of LPH fingerprinting analyses, benzene to xylene ratios, time of travel calculations, tank history, documented release history, degradation analysis, and gasoline additives information. Roux also evaluated the efficacy of current remediation systems and provided system modification changes and improvements.

Municipal Landfill TCE Plume Evaluation

Neil M. Ram, Ph.D., LSP, CHMM


Roux was retained to determine the time frame that a plume of chlorinated volatile organic compounds (CVOCs) first arrived at a Plaintiff’s residence and the concentration of such CVOCs to which the Plaintiff was allegedly exposed.


Using groundwater modeling and site-specific data, Roux’s experts concluded that vinyl chloride was the only CVOC detected in the Plaintiff’s water supply well during an approximate ten year span and that Trichloroethylene (TCE) was never detected in this well.


Regarding the timing of alleged exposures, Roux also determined that plaintiff’s only exposure to vinyl chloride occurred only for a brief period consisting of low concentrations (via drinking water ingestion and inhalation during showering) after which bottled water and a carbon filter system were provided.


Roux determined that the concentrations of vinyl chloride to which the plaintiff was likely exposed during this brief period were in the range of the Maximum Contaminant Level (MCL) in drinking water established by the U.S. Environmental Protection Agency (USEPA).

Paint Manufacturing Facility

Neil M. Ram, Ph.D., LSP, CHMM


Roux was retained by a Paint Manufacturer to determine the time of release for three chemicals identified in groundwater at the site: trichloroethylene, toluene and tetrachloroethylene. These chemicals were released from underground storage tanks at the subject site. Time of travel calculations in conjunction with plume length was used to estimate the timing and associated release of these three chemicals. In addition, biodegradation models (bioplume and biochlor) were also evaluated. Release timing was calibrated using observed field conditions. A sensitivity analysis was also conducted to evaluate the effect of varying model parameters (organic carbon content, hydraulic conductivity, hydraulic gradient) on the predicted release dates. Based upon the calculated release dates, site assessment and remediation costs were allocated to the prior owner of the property since releases had occurred during the prior owner’s tenure at the subject site.

Property Damage – Major Utility

Paul Roux, P.G.

New Jersey

Roux was retained by a major petroleum company to provide forensic analyses of soil and groundwater contamination at four gasoline stations in New Jersey. Roux evaluated all available historical data and deposition testimony of former operators in light of Roux’s own extensive experience with gasoline station operations. Roux then provided expert opinions regarding underground storage tank installation and monitoring, timing and sources of releases, and the investigation and remedial actions taken.


Roux’s expert reports were used to support a reduction in the cost contribution demanded from our client for past work at the sites.

Soil & Groundwater Contamination

Paul Roux, P.G.

New York

Roux was hired to provide a second opinion on a previous environmental investigation at a truck maintenance facility operated by a regional telephone company. As part of an underground storage tank (UST) replacement program, two gasoline USTs were removed and replaced at the site. No leakage or contamination was detected when the tanks were removed. Shortly after the tanks were removed, methyl tertiary butyl ether (MTBE), a gasoline additive, was detected in a nearby public supply well. At the request of the New York State Department of Environmental Conservation (NYSDEC), our client installed several monitoring wells on its property and detected MTBE but no other compounds. Based upon this result, the client’s contractor wrote a report indicating the site was the source of the MTBE. Subsequently the municipality that owned the impacted well filed suit against our client seeking damages. Roux recommended and conducted additional investigations that provided groundwater flow and geochemical data, indicating the source of the contamination was one or more upgradient gasoline service stations.


A report was prepared by Roux. Based on this report the lawsuit against our client was dropped.

Various Service Stations

Neil M. Ram, Ph.D., LSP, CHMM


Roux  was retained to determine the timing of releases that occurred at several gasoline service stations.


Roux utilized a number of forensic tools to identify the approximate date(s) of release(s) at these service stations. These tools included: evaluation of LPH fingerprinting analyses, chemical constituent ratios, time of travel calculations (groundwater modeling), tank history, documented release history, degradation analysis, and gasoline additives information. Lead isotope analysis and geochemical profiling have also been considered as forensic tools in assessing historical release time frames.


Important steps in performing these forensic included: (1) reviewing environmental databases and state and local records, (2) assembling and evaluating data, (3) identifying groundwater flow direction, (4) preparing environmental media contaminant isopleths, (5) evaluating the distribution and content of non-aqueous phase liquids, and (6) determining the presence of gasoline additives.