Oil-Specific Properties Summary Sheets for Spill Response

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					                                                                               1997 INTERNATIONAL OIL SPILL CONFERENCE                                  929

                                  SPILL RESPONSE

                            William R. Gala, Gary A. Rausina, Michael J. Ammann, Elizabeth A. Harvey,
                                              Patrick Y. O’Brien, and John P. Suzuki
                                           Chevron Research and Technology Company
                                                         100 Chevron Way
                                                Richmond, California 94802-0627

                                                               Lyman A. Young
                                                            Chevron Corporation
                                                              575 Market Street
                                                     San Francisco, California 94105-2856

                                       John Newman, Michael M. Singer, and Ronald S. Tjeerdema
                                              Department of Chemistry and Biochemistry
                                                University of California—Santa Cruz
                                                    Santa Cruz, California 95064

ABSTRACT: Chevron has developed oil-specific properties summary                 a wide range of environmental conditions on the summary sheet.
sheets for major crude and high-volume oil products to improve our             Another innovative approach used was to provide the aquatic toxicity
ability to provide timely and accurate information for decision-making         data as a function of total petroleum hydrocarbons, the sum of parent
processes in the initial stages of a spill and to help address questions       and alkylated polycyclic aromatic hydrocarbons (PAHs), and the sum
posed by trustees and the public. Each summary sheet is composed of            of monoaromatic hydrocarbons (benzene, toluene, ethyl benzene, and
five modules that denote (1) the oil’s physical and chemical properties;        xylene [BTEX]), so that environmental monitoring data can be com-
(2) the oil’s environmental fate; (3) spill countermeasures; (4) public        pared to relevant toxicity data for predictions on environmental impact
health and ecotoxicology data; and (5) appropriate analytical methods.         and damage.
Identified information gaps (i.e., aquatic toxicity, WAF chemistry, etc.)          The traditional characterization of crude oils is focused on analyses
are being addressed in Chevron-funded research at the University of            associated with the refining process, not oil spill response. The team
California—Santa Cruz.                                                         identified several data gaps for key parameters that are important in
                                                                               understanding the fate and effect of crude oils released into the envi-
                                                                               ronment. Some of these parameters are inherent characteristics, such as
                                                                               PAH and BTEX concentrations of crude oil. In addition, incomplete
Discussion                                                                     data (for example, percent aromatics, naphthenes, total paraffins,
                                                                               asphaltenes/resins, and sulfur) were discovered for many of the screened
   The purpose of this multiyear project is to provide spill responders        oils. Other data gaps included characteristics of the crude oil after it
with fact sheets listing key properties that influence the fate and            comes into contact with water. For example, the environmental impact
effects of Chevron crude oils and products that could be potentially           of an oil spilled on water will, in part, be related to the amount of oil that
released into the environment. The oil property summary sheets will            dissolves into the water (the water-accommodated fraction).
provide critical information on specific oils and products for quick              The Chevron team is working with researchers at the University of
reference in the field during the initial stages of an oil spill, while        California—Santa Cruz (UCSC), to fill the following identified data
more specific information on the oil is being compiled. The summary            gaps:
sheets will enhance the effectiveness of Chevron’s spill responders
by providing the following benefits: (1) they will help determine                • BTEX and PAH concentrations in selected bulk oils
and focus appropriate spill countermeasures and associated environ-              • BTEX, PAH, and TPH concentrations in their water-accommo-
mental monitoring activities; and (2) they will enable spill responders            dated fractions (WAF)
to provide prompt answers, with the best available information,                  • Aquatic toxicity of the WAF to a representative marine fish and
to questions raised by representatives of the incident command,                    invertebrate
agencies, and the public concerning the potential fate and effect of
a spilled oil.                                                                 Researchers at UCSC (Singer et al., 1990) have developed a toxicity test
   The oil-specific properties summary sheets consist of five modules            method that models conditions that occur in the field and that provides
detailing the oil’s physical and chemical properties (including its chem-      realistic results.
ical composition), its expected fate in the aquatic environment, possible
spill countermeasures, public health and ecotoxicology data, and appro-
priate analytical methods for measuring petroleum-related hydrocar-            Conclusions
bons and metals in water, soil, and air. Details of the components of each
module are provided in Table 1. For example, we used the National                 Although the tabulation of physical and chemical properties of
Oceanographic and Atmospheric Administration’s (NOAA) ADIOS                    selected crude oil and oil products is not new (e.g., Environment
model (version 1.1) to provide a predicted evaporation curve range (0 to       Canada, 1990), our approach is innovative because it focuses on pro-
72 hours) for each summary sheet. By including the model results for a         viding spill responders with information in a form that allows them to
high-energy (high water temperature and gale winds, i.e., 27°C, 24-knot        make timely decisions related to the fate and effects of the spilled oil,
winds) and low-energy (low water temperature and calm winds, i.e.,             and to provide guidance on the appropriate countermeasures and ana-
4°C, 5-knot winds) scenario, we could provide realistic evaporation esti-      lytical methods to use. Instead of just providing, for example, specific
mates (the most important loss process in the initial stages of a spill) for   gravity and asphaltene content values, we have translated the physical

  Table 1. Components of oil-specific properties summary sheets              and chemical attributes into the necessary answers to typical questions,
                                                                            such as “Will the oil sink?” or “Will it form an emulsion?”, using stan-
                                                                            dard rules of thumb. Thus these summary sheets will enable spill respon-
Physical chemical properties    Fate processes                              ders to make not only timely decisions, but also informed ones.
Density                         Evaporation
API gravity                     Mousse formation                            Biography
Vapor pressure                  Spill countermeasures
Viscosity                       Burning                                       William Gala has been an environmental toxicologist with Chevron
Pour point                      Dispersability                              for over 7 years, providing expert advice to Chevron facilities world-
Water solubility                Mechanical recovery                         wide on the fate, transport, and ecological effects of constituents in their
Interfacial tension             Toxicology                                  effluents and products. He is also a member of Chevron’s worldwide
Weight % fractions of oil       Worker exposure/public health               Environmental Functional Team for emergency responses.
   Aromatics                    Aquatic toxicity
   Naphthenes                   Suggested chemistry methods                 References
   Total and n-paraffins        EPA/NIOSH methods for extraction
   Asphaltenes/resins             and analysis of BTEX, TPH, PAHs           1. Environment Canada, 1990. A Catalogue of Crude Oil and Oil Prod-
   Sulfur                         and metals in oil, water, soil, and air      uct Properties, 4th edition. Environmental Emergencies Technology
BTEX, PAH and metal                                                            Division, Environment Canada, Ottawa, Canada
   concentrations in bulk oil                                               2. Singer, Michael M., D. L. Smalheer, R. S. Tjeerdema, and M. Mar-
                                                                               tin, 1990. Toxicity of an oil dispersant to the early life stages of four
BTEX and PAH                                                                   California marine species. Environmental Toxicology & Chemistry,
   concentrations in WAF                                                       v9, pp1387–1395


                                                        Jan Rusin and Tim Lunel
                                                          AEA Technology plc
                                               National Environmental Technology Centre
                                                    Culham, Abingdon, Oxfordshire

                                                            Andrew Tyler
                                                  BMT Marine Information Systems LTD
                                                       Southampton, Hampshire

ABSTRACT: On February 15, 1996, the Sea Empress went                        Modeling the short-term fate of the oil
aground at Milford Haven off the Pembrokeshire coast of South               and the surface trajectory
Wales, Great Britain. Between February 15 and 21 some 72,000
tons of Forties blend crude oil were released into the marine envi-            OSIS modeling was implemented within a couple of hours of
ronment. The model OSIS (oil spill information system) was de-              the Sea Empress going aground and was used routinely during the
veloped jointly by AEA Technology and BMT Marine Information                following week while oil was still being released into the marine
Systems. OSIS was successfully used by AEA Technology for the               environment (Lunel et al., 1996a). This modeling provided opera-
U.K. Coastguard Agency’s Marine Pollution Control Unit (MPCU)               tional advantages; predictions of the likely environmental fate of
as a response tool to predict the fate, trajectory, and likely beach-       the oil included information on its expected trajectory and partition-
ing of oil, thus aiding in the decisions and optimizing response            ing from the sea surface to the water column, and the atmosphere.
strategy. The MPCU has subsequently contracted AEA Technol-                 The model predicted the coastline at risk from stranded oil, the time
ogy to develop OSIS to predict the long-term fate of the dispersed          of beaching, and the amount of oil and emulsion expected to
oil and to identify areas of deposition following oil-sediment              beach. Thus the use of the model in conjunction with remote sensing
interaction.                                                                information allowed operators to develop and then execute a re-
                                                                            sponse strategy rather than react only to observed information.