Ref. No. [UMCES]CBL 2013-015
ACT VS12-02
compounds and with compounds at oil to dispersant ratio of 25:1. The test materials were created
experimentally at the Bedford Institute of Oceanography (Department of Fisheries and Oceans,
Halifax, Nova Scotia) using the two source oils and Corexit 9500 dispersant. Experiments were
performed in a step-up addition batch mode with breaking waves to physically disperse the oil
throughout the tank. Oil additions were cumulative to the same batch of water and were made at
six timepoints at approximately one hour intervals. The amount of oil added ranged between 0 to
360 grams and produced oil concentrations of 0, 0.3, 0.6, 1.5, 3.0, 6.0, and 12.0 ppm,
respectively, at each consecutive step. Reference sampling occurred 50 minutes after each new
oil addition. Continuous instrument records were sub-sampled to the last 10 minutes of
equilibrated conditions of the exposure period and corresponding reference sampling times.
A Seabird SBE26+ CTD, SeaPoint chlorophyll fluorometer and LISST particle analyzer
were deployed to provide ancillary time-series data on water quality and to confirm degree of
physical dispersion of added oil. Reference samples were collected from three sampling inlet
ports distributed across the width of the tank and located adjacent to the sensor window. An
aggregate sample was produced for the reference sample analyses, except for hydrocarbon
subsamples which were taken and analyzed independently. Hydrocarbon analysis was conducted
on-site by certified COOGER BIO facility personnel using either gas chromatography with a
flame graphite detector (GCFID) or gas chromatography with a mass spectrometer (GCMS)
depending on concentration levels.
Field Tests
Moored Deployment
A moored application test was conducted at the Maritime Environmental Resource
Center barge facility located within Winans Cove, Baltimore Harbor, MD (39.2614N,
76.6008W). The moored test was planned for a duration of four continuous weeks; however,
the test was cut short after 18 days due to the passage of Hurricane Irene. In addition, the
deployment was interrupted after day two due to a breakage in the mooring structure. The
mooring was re-established on August 18
th
and operated for 9 days prior to retrieval.
Instrument Setup
– The test instruments were programmed to record data at the highest
frequency that the instruments’ battery would maintain over the deployment period. The internal
clock was set to local time and synchronized against the time standard provided by
. A photograph of each individual instrument and the entire instrument rack was
taken just prior to deployment and just after recovery to provide a qualitative estimate of
biofouling during the field tests. Prior to deployment, the test instrument was exposed to freshly
prepared reference solutions (QS and NDSA) made up in DI water both before and after
deployment as an estimate of instrument reliability. The post-deployment reading was taken
after the instruments were cleaned according to manufacturer specifications.
Reference samples were collected on three days of each week at four separate times
spaced at one-hour intervals. Reference field samples were collected within 1 m from the sensor
window. The water samplers were soaked at sampling depth for 1 minute prior to sampling. All
sampling times were recorded on logsheets and entered into a database for final data
comparisons. Two standard 4L Van Dorn trace metal compatible water samplers were used to
collect duplicate water samples for reference measurements. The standard reference sample suite
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