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As analytic instruments and methods have improved over the decades, so too, have insights into the fate and behavior of oil–water mixtures. Particularly relevant are understanding and documenting oil phase signatures that, while yielding forensic insights in our early studies, have led to the recent development of phase-specific methods appropriate for the forensic study of oiled water. The forensic applications of these methods include source matching, weathering, deconfounding background contaminants, distinguishing dissolved and particulate phases within whole water samples, and documenting chemical dispersant effects on polycyclic aromatic hydrocarbons (PAH) profiles. These methods, when collectively applied to deep-sea water of the Gulf of Mexico following the Deepwater Horizon (DWH) blowout, were used to ultimately track the subsurface plume of DWH-impacted water 412 km across the Gulf of Mexico to a final sample confirmed with only a trace dissolved-PAH pattern and supporting information.

After a spill, oil is present in water as both dissolved and particulate (oil-droplet) phases due to entrainment and dissolution/weathering processes. The two phases, capable of physically separating and remixing in a body of water, complicate forensic evaluations but also contribute information on waterborne fate and transport. Identifying and tracking each phase in field samples has high forensic value in developing interpretive scenarios of weathering and exposure processes and for providing data germane to modeling and toxicology studies in damage assessments. Samples can be parsed into phase components either physically in the field using portable filtration equipment or later with data evaluation methods developed to parse out unfiltered samples using a weathered particulate-oil reference series generated from a few field-filtered samples. If done properly, sampling the water column for oil hydrocarbons during or after an oil spill can be highly insightful but the task is challenging and technically demanding with multiple opportunities to get it wrong, especially without feedback until weeks or months later when the data come back from the lab. This chapter presents water-sampling issues (and solutions), methods of forensically assessing quantified data, and adaptive sampling strategies that prove effective in tracking a deep submerged plume.

The need to prove and improve the adequacy of design factors used by the ASME B&PV CODE rules for gaskets has been the subject of an ongoing industry sponsored research program directed by the Pressure Vessel Research Committee (PVRC). Extensive work over the past several years has characterized gasket behavior and extracted new tightness based gasket constants from experimental leakage gasket data. This presentation examines flange facing surface finish effects on the new gasket constants. A PVRC research goal has been to provide industry with more meaningful experimentally supported gasket factors. Since initiated, over three dozen different gasket styles (sheets, jacketed, spiral wound, solid metal, etc.) and material/facing combinations have been studied with hundreds of room temperature leakage tests. Among other parameters, the effect of five flange facing surface finishes ranging from 0.81 to 25.4 micro-m AARH (32 to 1000 micro-in) on the tightness of three gasket styles was experimentally studied by the “Milestone” portion of the PVRC's Gasket Test Program II. Results are reported by Bazergui (1984) in terms of deflection, stress and tightness. This presentation reviews how that data is interpreted in terms of the new gasket constants, B, d and S*.

This paper presents an overview of the Pressure Vessel Research Committee's Flanged Joint Improvement Program. Responding to a request from the ASME Code Committee on the validty of Code gasket factors, the Subcommittee on Bolted Flanged Connections embared on an industry sponsored gasket research program. A goal of the PVRC effort is to provide industry with gasket performance data that is suitable for reduction to more meaningful experimentally supported Code gasket factors. A related goal is to define ASTM type test method enabling manufacturers to certify gasket performance in a widely accepted and standard manner. Significant progress has been made with ambient temperature programs which now reflect the experience of hundreds of individual leakage tests on over three dozen different gasket styles or material/facing combinations. Also an elevated temperature program is now well underway. This paper discusses some of the findings of the “Exploratory Test” program and “Gasket Type Program II.” Procedures are proposed for interpreting gasket data obtained from the “Production Test” for design use. Empirically derived gasket design constants for ASME Code use based on provisional joint tightness criteria and improved procedures for numerically interpreting the test data are presented. Seating, initial preload and joint efficiency are considered among other parameters. The concept of tightness ratio, the idea of ambient tightness and joint assembly are also briefly discussed.