Page 8 - Performance Verification Statement for the Chelsea UV Aquatracka Fluorometer

Ref. No. [UMCES]CBL 2013-014
ACT VS12-01
calibrated RBR 1060 recording thermometers. Each test level began with a 30 minute
equilibration, and reference water samples were collected at 10 minute intervals over the
following 30 minute exposure. Instrument response, reported as the average of 5 minutes of
readings encompassing reference sample times, was used to characterize instrument response at
each challenge level. Instrument response factors are calculated by regression of mean
instrument output against challenge compound concentrations. Precision tests were conducted
by monitoring the variance of instrument response over the 5 minute periods. Originally
proposed turbidity and CDOM interference tests, and temperature response factors, were not
conducted.
Table 1. Challenge compounds for laboratory evaluations of hydrocarbon sensors.
Compound Ex Em Carrier Stock (ppm)
Carbazole 270 342, 358 methanol 5000
1,5-Naphthalene
Disulfonic Acid
270 380 0.05 M H2SO 4 5000
Quinine Sulfate 350 450 0.05 M H2SO 4 5000
Basic Blue 3 250, 320 430 water 5000
Diesel Fuel
SPEX CRM
250-300 350-500 methanol 5000
Performance against crude oils and dispersants in a Wave Tank Test
A test application of instrument response against crude oil compounds, with and without
addition of dispersant, was performed in a simulated water column using the DFO/US EPA
Wave Tank Facility located at the Bedford Institute of Oceanography, Dartmouth, Nova Scotia,
Canada. Reference samples were collected from the tank to allow real-time characterization of
the sample water with three-dimensional Excitation/Emission spectroscopy (EEMS).
Instrument performance was examined against two types of crude oil, Arabian Light
(weathered 7%) and Alaskan North Slope, run under two conditions including the pure oil
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
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