Joint and several liability provisions and quests to obtain insurance coverage from historic general liability insurance policies for the remediation of contaminated sites have become some of the more effective aspects of environmental litigation. These aspects encourage parties saddled with extensive cleanup problems to pursue former owners, operators, and insurance carriers in an attempt to recoup some of their financial losses. Insurance companies are perhaps the current largest target of the growing environmental litigation industry.
The critical issue in such litigation is the identification of appropriate parties or sources responsible for pollutants found on contaminated properties. EWMA employs a method called plume dating to identify both the parties responsible for and the time of release of contamination. Plume dating can potentially allow the minimization of liability, and an equitable allocation of remedial expenses.
EWMA's version of plume dating consists of a unique, multi-faceted approach to dissect the site information and establish the issues critical to contaminant source, fate, and transport. EWMA's approach consists of four main aspects:
1. a chemical "fingerprint" of the identity, type, and amounts of contaminants present, including an evaluation of relative ratios of contaminants and presence (or absence) of marker compounds;
2. an assessment of site-specific geology and hydrogeology and their impacts on contaminant transport;
3. an evaluation of the parameters necessary for microbial degradation mechanisms and their effects, if any, on contaminant profiles and persistence; and
4. an engineering analysis of the site, including corrosion rates, soil permeability and the feasibility and efficiency of remedial actions.
Overall, the combination of these aspects results in an understanding of important biological, physical, and chemical processes on-site that can have an impact on contaminant profiles and mobilities. More importantly, the assessment facilitates both spatial and temporal modeling of contaminant transport, allowing a comparison and/or correlation with actual site conditions.
To continually refine our ability to assess fate and transport of chlorinated and petroleum-derived contamination, EWMA draws on extensive practical experience in site remediation. Our personnel conduct research on topical issues in the field, such as contaminant transport in fractured media, as well as maintain a current database of relevant literature and forensic testing labs in the field.
Fingerprinting
Practically speaking, identification of a petroleum product based on the presence or absence of marker compounds is optimal for heavier petroleum fractions (various grades of diesel fuel and heating oil). Gasoline mixtures often have proprietary additives and blending agents that allow the estimation of age and identity of the product. Heavier petroleum fractions contain bioresistant compounds that can accurately reflect the crude stock from which the fraction originated. Analysis of these compounds, as well as their relative amounts in a sample, can also reflect the age of a product found during a remedial investigation.
The most famous case using such "fingerprinting" techniques is exemplified by the millions of dollars spent in assessing contamination from the Exxon Valdez oil spill near Alaska's Prince William Sound. In those studies, numerous consultants determined independently that some of the areas with contamination had been impacted by other spills not associated with the Valdez. The pioneering and extensive analytical work associated with the Valdez spill also resulted in an optimization of fingerprinting analytical methods and interpretive techniques, facilitating a better understanding of the effects of weathering processes on a petroleum product's chemical profile.
Case Studies
EWMA's approach to plume dating has been successfully used in cases involving spills or leaks of petroleum (gasoline or heavier fractions) or other chemicals (i.e. chlorinated solvents). The technique can often distinguish between multiple, distinct plumes and plumes resulting from chronic leakage or leaching.
One of EWMA's original applications of the technique was in the determination of the age and source of soil and ground water contamination near a gasoline station in Passaic County, New Jersey. EWMA represented the property owner of the gasoline service station; a major oil company had operated the site for approximately 10 years. A significant number of potable supply wells had been impacted by ground water contamination, and the focus of the litigation was the determination of the approximate date of release from the on-site tanks. To date the plume, EWMA reviewed historical site information and performed site investigations. EWMA also critically analyzed contaminant transport models and assumptions used by the oil company's consultants and reviewed deposition testimony. EWMA was able to show that the contamination resulted from recent spills and/or leaks during the tenure of the oil company, with the net result being a settlement in favor of the property owner.
In another typical case, EWMA was able to demonstrate using biodegradation rates, contaminant profiles, and the presence of certain gasoline additives that contamination on-site was the net result of overlapping new and old plumes. In this way, insurance coverage was obtained to defray some of the remedial expenses.
EWMA has also estimated corrosion rates to determine the approximate formation rate of holes in underground tanks. This information, when paired with estimated transport rates and an assessment of biodegradation rates, gives EWMA's plume dating approach further aspects of flexibility and depth.
The dating of a release involving chlorinated compounds can be particularly complex. In cases involving chlorinated contaminants, EWMA has relied on an in-depth analysis of the site-specific geology and hydrogeology to address contaminant transport rate and removal. Additionally, EWMA focuses its analyses on the known chlorinated degradative pathways, both aerobic and anaerobic, to determine the primary transformation mechanisms occurring at a site. By focusing on hydrogeologic and chemical/microbiological features that are dominant at a particular site, EWMA has been able to correlate a projected or "modeled" plume and its chemical profile with those seen on-site. Importantly, EWMA has been able to analyze similar assessments of other consultants and to critique unsupportable assumptions.
In summary, EWMA's multi-variate analysis allows a broad range of compounds to be "dated" and gives us the flexibility to be able to solve multiple problems within a specified work scope.
For a confidential analysis of your case, please call EWMA at 800-969-3159.