Page 10 - Performance Verification Statement for the Chelsea UV Aquatracka Fluorometer

Ref. No. [UMCES]CBL 2013-014
ACT VS12-01
each profile, reference samples were collected during the upcast at five discrete depths spaced
throughout the water column. On each cast, one of the five discrete depths was sampled in
replicate with two independent water collection bottles. At each of the selected depths, the
rosette was paused for 1 minute to ensure that the test instrument had stabilized prior to water
sampling. The rosette and test instrument assembly were lowered and raised at a standard rate
of approximately 0.25 m/sec. All test instrument and reference sample data are shown for the
upcast only to match up sampling times. Temperature and salinity profiles are taken from the
undisturbed, continuous downcast. If the test instrument was not internally logging, it was
connected to a common WET Labs DH4 datalogger powered with an external battery package.
The reference water sample data were matched up with the hydrocarbon sensor data by
averaging the instrument readings for 10 seconds before and after the specific time the water
bottle was fired.
Ancillary In Situ Environmental Data
In-situ measurements were generated every 15 minutes over the duration of the moored
field tests. A calibrated YSI sonde and three RBR 1060 temperature loggers were attached to the
mooring. In conjunction with each water sample collection, technicians recorded basic site-
specific conditions on standardized log sheets including: date and time, weather conditions (e.g.,
haze, % cloud cover, rain, wind speed/direction), recent large weather events or other potential
natural or anthropogenic disturbances, tidal state and distance from bottom of sensor rack, and
any obvious problems or failures with instruments.
Ancillary data is presented to provide a general history of weather patterns and changes
in ambient water quality conditions. These data were not used for any direct calibration,
correction, or statistical comparison to the reported test data.
Quality Assurance/Quality Control
This Performance Verification was implemented according to the QA test plans and
technical documents prepared during planning workshops and approved by the manufacturer and
the ACT hydrocarbon sensor advisory committee. Technical procedures included methods to
assure proper handling and use of test instruments, laboratory analysis, reference sample
collections, and data. Performance evaluation, technical system, and data quality audits were
performed by QA personnel independent of direct responsibility for the verification test. All
implementation activities were documented and are traceable to the Test/QA plan and to test
personnel.
The main component to the QA plan included technical systems audits (TSA) conducted
by an ACT Quality Assurance Manager of the laboratory tests at MLML and of the field test in
Baltimore Harbor to ensure that the verification tests were performed in accordance with the test
protocols and the ACT Quality Assurance Guidelines. All analytical measurements were
performed using materials and/or processes that are traceable to a Standard Reference Material.
Standard Operating Procedures were utilized to trace all quantitative and qualitative
determinations to certified reference materials. Lastly, ACT’s QA Manager audited
approximately 10% of the verification data acquired in the verification test to assure that the
reported data and data reduction procedures accurately represented the data generated during the
test.
10