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8.0 SPILL COUNTERMEASURES R&D
8.1 In-situ Burning and the Newfoundland Offshore Burn
Experiment (NOBE)
8.2 Chemical Spill-treating Agents
8.3 Sorbent Evaluation
8.4 Mechanical Containment and Recovery Equipment
Evaluation
8.5 Standards Development
8.1 In-situ Burning and the Newfoundland Offshore Burn
Experiment (NOBE)
Several recent large accidental oil spills have re-confirmed that shoreline oil
contamination causes extensive environmental damage and results in very high cleanup
costs. Analysis of the Exxon Valdez oil spill indicated that perhaps more than half
of the spilled oil could have been burned in-situ without igniting the oil
remaining in the vessel, thereby significantly reducing shoreline contamination.
Intensive laboratory and tank testing on the in-situ combustion of oil indicated
that the nature and concentrations of atmospheric emissions from in-situ burning of
oil offshore would sometimes be preferable when weighed against the environmental damage
and cleanup costs of nearshore and shoreline contamination. Studies on the emissions of in-situ
burns were continued. A series of meso-scale burns were conducted in Mobile, Alabama in
1997. The ETC joined with the U.S. EPA in establishing an extensive monitoring program for
emissions. Data analysis continues.
Data analysis also continued on several extensive burn studies conducted in the past.
These studies show that combustion gases including carbon dioxide, sulphur dioxide, and
carbon monoxide did not reach levels of high concern. These gases were emitted over a
broad area around the fire and were not directly associated with the plume trajectory.
Volatile organic compounds (VOCs) were abundant, but at lower levels than those emitted
from an equivalent non-burning spill. Over 140 compounds were quantified, several at
levels near human health exposure maximums up to 100 m downwind.
Water under the burns was analysed for volatile compounds. No compounds were found at
the detection level of the methods employed.
Airborne particulate material, the starting oil, and subsequent burn residues were
analysed for metals. Metals were not detected on the airborne particulate material - other
than small amounts derived from the fire-resistant boom used to contain and thicken the
slick. Slightly elevated metal concentrations, above that noted in the starting oil, were
found in the residue, indicating that metals are largely deposited in the burn residue,
rather than released in the smoke and soot particles.
Polycyclic aromatic hydrocarbons (PAHs) were found at lower concentrations in the soot
than in the starting oil, and were consumed by the fire to a large degree. Particulate
matter in the air was measured by several means and found to be of concern only up to 150
m downwind at sea level.
8.2 Chemical Spill-treating Agents
Since treatment of oil or chemical spills involves applying additional chemicals to the
environment, it is essential that adequate information is available about the toxicity and
effectiveness of these chemicals. The ETC is developing and implementing tests for this
purpose. Performance tests will ultimately be developed for 12 classes of chemical
spill-treating agents. So far, tests have been developed for dispersants, solidifiers, and
surface-washing agents. Over 100 agents from these three classes have been tested in
recent years. Test have been developed for emulsion breakers, recovery enhancers, and
emulsion preventers. Work is continuing on the testing of new agents.
The chemistry (especially stability over periods approaching days) and physics
(especially dispersant particle size) of dispersants are being studied. In addition, work
is continuing on the development of new dispersants. Some of the prototype formulations
offer potential to disperse heavy oils, including Bunker-C.
Environment Canada and the U.S. Minerals Management Service jointly fund this work.
8.3 Sorbent Evaluation
The ETC has continued to lead a project to develop an improved performance
standard for the testing of oil spill sorbents. A Canadian General Standards Board testing
protocol was developed earlier, which targets performance parameters for sorbents used to
combat oil spills. Additional work was performed to ensure that compatible testing
protocols were developed in the U.S. Results to date have been tabulated in a database
that will be made available as a public resource on the Internet.
Development has also been continued on a similar protocol and test program targeting
sorbents used for chemical spills. Sorbent performance and chemical compatibility were the
initial parameters investigated.
8.4 Mechanical Containment and Recovery Equipment Evaluation
A technical working group led by a Norwegian research institute, SINTEF NHL, and with a
number of international partners has been attempting to improve the current
state-of-the-art technologies for recovery of oil spills in ice-infested waters. The name
of the project is "MORICE", which stands for "mechanical oil recovery
in ice-infested waters". Environment Canada (ETC) and the Canadian Coast Guard
have jointly participated during the report period as members of the working group, in two
workshops designed to review the advantages and limitations of available technologies, and
to examine the feasibility and advantages of potential new designs and concepts. This
study, now entering its third phase, has already completed lab testing of some promising
prototypes and undertaken detailed engineering analyses to improve current techniques.
8.5 Standards Development
Since 1991, the ETC has been involved in a program of standards development for oil
spill cleanup in partnership with agencies such as the U.S. Coast Guard, which is
responsible for administering the Oil Pollution Act, 1990 (OPA 90), and
other research and industrial groups concerned with marine oil spill response
technologies. The standards for mechanical containment and recovery continue to be
developed through the applicable American Society for Testing and Materials (ASTM) F-20
sub-committee to ensure compatible standards for North America, at least. The ETC is also
participating in developing standards for other areas such as sorbents (Section 8.3),
remote sensing, dispersants, communications, and in-situ burning.
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appendices
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