Arrange the following steps in performance evaluation in logical order:

Question

Arrange the following steps in performance evaluation in logical order:

I. Compare effluent quality with standards

II. Collect and analyse samples

III. Calculate removal efficiencies (%)

IV. Identify operational issues

Choose the correct sequence:

1. A. II-III-I-IV (Correct answer)
2. B. II-I-III-IV
3. C. III-II-IV-I
4. D. I-II-III-IV

Correct Answer

Option A — II-III-I-IV

Detailed Solution & Explanation

The correct answer is II-III-I-IV.

Key Points

• Performance evaluation follows a fixed logical order, because each step depends on the one before it:
  • II. Collect and analyse samples — nothing can be assessed without data.
  • III. Calculate removal efficiencies — convert influent and effluent figures into percentage removal across each unit.
  • I. Compare effluent quality with standards — judge the results against the statutory discharge limits.
  • IV. Identify operational issues — diagnose the cause of any shortfall and act on it.
• Sampling must come first and diagnosis last; the options that begin with comparison or calculation put the conclusion before the evidence.

Additional Information

• The order mirrors the general monitor → analyse → evaluate → act cycle used in all environmental management systems, and it is the same logic underlying the Plan-Do-Check-Act loop of ISO 14001.
• Sampling technique determines everything downstream. Composite samples taken over 8 or 24 hours represent average loading properly, while grab samples capture a single moment and are appropriate only for parameters that change quickly, such as pH, DO and temperature.
• Removal efficiency is computed unit by unit, not merely across the whole plant, because that is what localises a fault to a particular tank.
• The final step closes the loop: identified issues feed back into operating adjustments — F/M ratio, sludge wasting rate, aeration — and the cycle repeats.