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Test Yourself—Donna Kaluzniak
Test Yourself What Do You Know About Water and Wastewater Disinfection Rules?
Donna Kaluzniak
1. Per Florida Administrative Code (FAC) 62555, Permitting, Construction, Operation, and Maintenance of Public Water Systems, suppliers of water shall maintain a minimum chlorine residual throughout their drinking water distribution system at all times. The minimum free chlorine residual is 0.2 mg/L and the minimum combined chlorine residual is a. 0.3 mg/L. b. 0.4 mg/L. c. 0.5 mg/L. d. 0.6 mg/L.
2. Per FAC 62-555, for each day a supplier of water serving 3,300 or more persons serves water to the public from a drinking water treatment plant using chemical disinfection for virus inactivation, they shall continuously monitor the residual disinfectant concentration (C) before or at the first customer and shall record in the logs the lowest C measured during peak flow, the corresponding disinfectant contact time (T) at the C monitoring point during peak flow, and the resulting lowest CT provided before or at the first customer during peak flow. What other measurements must be taken at least once per day at the C monitoring point? a. pH and E. coli b. pH and Cryptosporidium c. pH and temperature d. Temperature and flow
3. Per FAC 62-550, Drinking Water Standards,
Monitoring, and Reporting, the maximum residual disinfectant levels (MRDLs) for both chlorine and chloramines is 4 mg/L. What is the
MRDL for chlorine dioxide? a. 0.4 mg/L b. 0.6 mg/L c. 0.7 mg/L d. 0.8 mg/L
4. Per FAC 62-600, Domestic Wastewater
Facilities, the criteria required for wastewater facilities to meet high-level disinfection includes any one effluent sample that shall not exceed 25 fecal coliform values per 100 mL of sample.
Over a 30-day period, what percent of fecal coliform values must be below detection limits? a. 50 percent b. 60 percent c. 75 percent d. 90 percent 5. Per FAC 62-555, following disinfection of a new or altered well, a bacteriological survey of the well must be conducted. Unless modified by the Florida Department of Environmental
Protection (FDEP), what is the required minimum number of samples to be collected? a. 10 b. 15 c. 20 d. 25
6. Per FAC 62-555, if the results of a bacteriological survey of a well determines that the well is microbially contaminated or susceptible to microbial contamination, the supplier of water must provide treatment that reliably achieves at least what level of inactivation or removal of viruses? a. One-log b. Two-log c. Three-log d. Four-log
7. Per 62-555, bacteriological evaluations to verify proper disinfection of treatment or storage facilities and water mains requires a total of at least two samples—each taken on a separate day and taken at least six hours apart from the other sample(s) and analyzed for total residual chlorine and for the presence of total coliform. Prior to taking the samples, the total chlorine residual in the facilities or mains must be reduced to no more than a. 1 mg/L. b. 2 mg/L. c. 3 mg/L. d. 4 mg/L.
8. Per the FDEP website, Ultraviolet (UV)
Disinfection for Domestic Wastewater, FDEP will accept UV designs that comply with National
Water Research Institute (NWRI) guidelines, supported with validation testing to provide reasonable assurance that a domestic wastewater treatment facility can meet high-level disinfection criteria. Per the NWRI “Ultraviolet Disinfection
Guidelines for Drinking Water and Water Reuse” (NWRI UV Guidelines), the UV dose is expressed as the product of UV intensity and a. exposure time. b. transmittance level. c. turbidity value. d. volume of water.
9. Per the NWRI UV Guidelines, the design of a
UV disinfection system for water reuse depends on what type of technology preceding it? a. Aeration b. Biological nutrient removal c. Filtration d. Sedimentation 10. Per FAC 62-610, Reuse of Reclaimed Water and Land Application, which type of reuse application requires high-level disinfection? a. Slow-rate land application, restricted public access b. Slow-rate land application, public access areas c. Rapid-rate land application systems d. Overland flow systems
Answers on page 50
References used for this quiz: • Florida Administrative Code 62-550, Drinking
Water Standards, Monitoring and Reporting: https://www.flrules.org/gateway/ChapterHome. asp?Chapter=62-550 • Florida Administrative Code 62-555, Permitting,
Construction, Operation and Maintenance of
Public Water Systems: https://www.flrules.org/gateway/ChapterHome. asp?Chapter=62-555 • Florida Administrative Code 62-600, Domestic
Wastewater Facilities: https://www.flrules.org/gateway/ChapterHome. asp?Chapter=62-600 • Florida Administrative Code 62-610, Reuse of
Reclaimed Water and Land Application: https://www.flrules.org/gateway/ChapterHome. asp?Chapter=62-610 • Florida Department of Environmental Protection website, Ultraviolet (UV) Disinfection for
Domestic Wastewater: https://floridadep.gov/water/domesticwastewater/content/ultraviolet-uv-disinfectiondomestic-wastewater • National Water Research Institute, 2012 –
“Ultraviolet Disinfection Guidelines for Drinking
Water and Water Reuse”: https://www.nwri-usa.org/research
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