What is the maximum monthly count for E. coli?

• A. 130 monthly average
• B. 240 max
• C. 400 max
• D. 50 max

Answer: (B)

E. coli is used as an indicator of fecal contamination in wastewater, and limits are set as counts per 100 mL. A maximum monthly count represents the highest allowable value for any sample within a month. The monthly maximum commonly used in Kentucky wastewater permits for E. coli is 240 CFU per 100 mL, which is why this option is correct. The other numbers correspond to different metrics or are not aligned with the monthly maximum: a monthly average (130) is a different compliance target, 400 max would be more permissive, and 50 max is unrealistically strict for a monthly limit.