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The individual collecting the sample is personally responsible for the handling and custody of the sample
until it is transferred to the individual responsible for analyzing the sample. The MERC PC determines
whether proper custody procedures are followed during the field work and decides if additional samples
are required due to improper sample handling.
Chain-of-custody procedures are strictly followed for all samples that are transported from the Mobile
Test Platform to MERC Partner and contracted analytical laboratories so that the possession of a sample
from the time of its collection until the time of its analysis is traceable and documentable. These
procedures not only guarantee the integrity of a sample (i.e., that it was properly prepared, preserved
and/or handled leading up to analysis), but also alleviate the possibility of sample mix-ups and/or
extraneous contamination.
A person will have custody of a sample when the samples are:
•
in their physical possession;
•
in their view after being in their possession;
•
in their personal possession and secured to present tampering;
•
in a restricted area accessible only to authorized personnel;
•
the person is one of the authorized personnel.
Field custody documentation will consist of both field log books and chain of custody forms. Completed
chain-of-custody forms will be required for all samples to be analyzed. Chain-of-custody forms will be
filled-out by MERC field sampling staff during the sample collection events. The chain-of-custody form
will track sample release from the sampling location to the analysis laboratory. The chain-of-custody
form will contain each sample’s:
•
unique identification number;
•
sample date and time;
•
sample description;
•
sample type
•
sample preservation (if any);
•
analyses required.
The original chain-of-custody form will remain with the samples at all times. Each form will be signed
by the person relinquishing samples once that person has verified that the chain-of-custody form is
accurate. Copies will be made prior to shipment for separate field documentation and retained by the
individual relinquishing the sample.
Upon arrival at the analysis laboratory, chain-of-custody forms will be signed by the person receiving the
samples (if different from the sample collector) once that person has verified that all samples identified on
the chain-of-custody forms are present.
Laboratory sample custody will be performed in accordance with the laboratory's Quality Assurance
Manual and SOPs and will be consistent with the guidelines set forth in this section of the QAPP. The
procedures should include but not be limited to documenting the following information:
•
presence or absence of chain-of-custody forms,
•
presence of absence of bills of lading
•
presence or absence of custody seals on shipping and/or sample containers and their conditions,
•
presence or absence of sample labels,