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CWEA ECI Grade 1 KSA 101-109 Questions and Answers with
Complete Solutions UPDATED!!!
Primary goal of sampling in wastewater management - ANSWER
To obtain representative samples that provide accurate data for
compliance monitoring, process control, or research purposes.
Two main types of samples used in wastewater sampling -
ANSWER Grab samples and composite samples.
When should a grab sample be used - ANSWER When a sample
is needed to represent the conditions at a specific point in time.
What is a composite sample - ANSWER A collection of individual
samples taken at regular intervals over a period, combined to
reflect average conditions.
Why is sample preservation important in wastewater sampling -
ANSWER To prevent changes in the sample composition due to
chemical reactions, biological activity, or physical changes
during storage and transport.
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Common preservatives used in wastewater sampling - ANSWER
Acidification (e.g., with sulfuric acid) to lower pH, refrigeration,
and the use of chemical preservatives to inhibit biological
activity.
Purpose of a Chain of Custody (COC) in sampling - ANSWER It is
a legal record that tracks the possession, handling, and location
of samples from collection to analysis, ensuring sample integrity
and admissibility in legal proceedings.
Safety precautions during sampling - ANSWER Use personal
protective equipment (PPE), follow safety protocols for handling
hazardous materials, and ensure proper training in sampling
procedures.
How should samples be transported to the laboratory -
ANSWER In a manner that preserves their integrity, typically in
coolers with ice packs to maintain a low temperature.
Role of Quality Assurance/Quality Control (QA/QC) in sampling -
ANSWER To ensure the reliability and accuracy of sampling and
analysis by minimizing errors and verifying that methods meet
regulatory standards.
CWEA ECI Grade 1 KSA 101-109 Questions and Answers with
Complete Solutions UPDATED!!!
Primary goal of sampling in wastewater management - ANSWER
To obtain representative samples that provide accurate data for
compliance monitoring, process control, or research purposes.
Two main types of samples used in wastewater sampling -
ANSWER Grab samples and composite samples.
When should a grab sample be used - ANSWER When a sample
is needed to represent the conditions at a specific point in time.
What is a composite sample - ANSWER A collection of individual
samples taken at regular intervals over a period, combined to
reflect average conditions.
Why is sample preservation important in wastewater sampling -
ANSWER To prevent changes in the sample composition due to
chemical reactions, biological activity, or physical changes
during storage and transport.
, 2|Page
Common preservatives used in wastewater sampling - ANSWER
Acidification (e.g., with sulfuric acid) to lower pH, refrigeration,
and the use of chemical preservatives to inhibit biological
activity.
Purpose of a Chain of Custody (COC) in sampling - ANSWER It is
a legal record that tracks the possession, handling, and location
of samples from collection to analysis, ensuring sample integrity
and admissibility in legal proceedings.
Safety precautions during sampling - ANSWER Use personal
protective equipment (PPE), follow safety protocols for handling
hazardous materials, and ensure proper training in sampling
procedures.
How should samples be transported to the laboratory -
ANSWER In a manner that preserves their integrity, typically in
coolers with ice packs to maintain a low temperature.
Role of Quality Assurance/Quality Control (QA/QC) in sampling -
ANSWER To ensure the reliability and accuracy of sampling and
analysis by minimizing errors and verifying that methods meet
regulatory standards.
