Wood Destroying Organism (WDO) Home Inspection Practice Exam

What should be tested in a well to determine potential contamination?

1. Turbidity

2. pH and iron

3. Water flow and capacity

4. Coliform bacteria

The correct answer is: Coliform bacteria

Testing for coliform bacteria in a well is essential for determining potential contamination because these bacteria serve as indicators of microbial contamination in water supplies. The presence of coliform bacteria signals that disease-causing organisms may be present, which could pose serious health risks if ingested. Coliforms are naturally found in the environment, particularly in soil and vegetation, but their presence in drinking water suggests that fecal contamination has occurred, potentially introducing pathogens. While turbidity, pH, and iron levels are also important parameters in assessing water quality, they do not specifically address the potential for harmful biological contaminants as effectively as coliform testing. Turbidity might indicate physical impurities, and extreme pH levels can affect the corrosiveness of the water, while iron is more related to aesthetic quality and staining rather than safety. Water flow and capacity tests measure the well's performance and sustainability but do not provide insights into microbiological safety. Therefore, testing for coliform bacteria is the most critical action when evaluating the safety of a well water supply.