Tennessee Wastewater Operator Practice Exam

What characteristics of receiving water must be measured immediately after sample collection?

1. Temperature, pH, and dissolved gases

2. Color, turbidity, and chemical composition

3. Dissolved oxygen, BOD, and temperature

4. Conductivity, nutrients, and temperature

The correct answer is: Temperature, pH, and dissolved gases

The correct answer highlights that temperature, pH, and dissolved gases are critical characteristics of receiving water that must be measured right after sample collection. This is primarily due to the fact that these parameters can change rapidly and may significantly influence the overall health and quality of the water body being tested. Temperature is crucial because it affects the solubility of gases and the metabolic rates of aquatic organisms. pH is important as it can influence chemical speciation, toxicity levels of pollutants, and biological processes. Dissolved gases, particularly oxygen and carbon dioxide, are vital for assessing the biological health of the water body, as they affect the respiration of aquatic life. The immediacy of measuring these characteristics ensures that the data reflects the true conditions of the water at the time of sampling, which is essential for effective water quality management and regulatory compliance. While the other choices include relevant parameters, they do not all necessitate immediate measurement after sample collection. For example, color and turbidity can often be measured with less urgency as they do not change as quickly as temperature or pH, and chemical composition might require more detailed analysis that can be conducted later in a laboratory setting. Similarly, while dissolved oxygen, biochemical oxygen demand (BOD), and nutrients are important,