Which type of sampling uses probability or chance to assess site contamination cost-effectively?

Which type of sampling uses probability or chance to assess site contamination cost-effectively?

• A. Statistical
• B. Non-statistical
• C. Qualitative sampling
• D. Targeted sampling

Answer: (A)

Using probability to make inferences about contamination across a site is the essence of statistical sampling. When you design a statistical sampling plan, you select sample locations using random or probability-based methods so every part of the site has a known chance of being included. This randomness lets you estimate the overall level of contamination from just a subset of measurements and attach measures of uncertainty (like confidence intervals), which makes the assessment cost-effective because you don’t have to sample everywhere. Other approaches rely on judgment, convenience, or prior knowledge rather than formal probability. They may describe conditions or identify hotspots but don’t support probabilistic generalizations about the whole site, which is why they aren’t the best fit for achieving cost-effective, inference-based assessments.

Using probability to make inferences about contamination across a site is the essence of statistical sampling. When you design a statistical sampling plan, you select sample locations using random or probability-based methods so every part of the site has a known chance of being included. This randomness lets you estimate the overall level of contamination from just a subset of measurements and attach measures of uncertainty (like confidence intervals), which makes the assessment cost-effective because you don’t have to sample everywhere.

Other approaches rely on judgment, convenience, or prior knowledge rather than formal probability. They may describe conditions or identify hotspots but don’t support probabilistic generalizations about the whole site, which is why they aren’t the best fit for achieving cost-effective, inference-based assessments.