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Health Based Targets - Risk Assesement v3

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* LRV - Log Reduction Value

System Name:

System Type: ?

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Choose Source Water Category Category 1 Category 2 Category 3 Category 4   RSource water category - ADWG 6 2011 version 4.0 Updated June 2025, Tables 5.2 and 5.5

LRV

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1. Catchment Protected?

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Choose Highly Protected Moderately Protected Minimally Protected or Unprotected   RCatchment - ADWG 6 2011 version 4.0 Updated June 2025, Table A1.8

LRV

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2. Raw Water Storage Detention  RRaw Water - ADWG 6 2011 version 4.0 Updated June 2025, Table A1.8

Raw water storage capacity

ML

Minimum operating level

%

Peak maximum daily flow out

ML

B

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Storage Retention Time:

days

LRV

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3. Filtration  ?

Choose Type Slow Sand Filtration Conventional Filtration Direct Filtration Micro Filtration Ultra Filtration Ineffective or No Filtration    RFiltration - ADWG 6 2011 version 4.0 Updated June 2025, Table 5.6/USEPA 2006 National Primary Drinking Water Regulations: Long term enhanced surface water treatment rule for Filtration section.

B

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LRV

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4. Ultra Violet Light Disinfection (UV)

Choose Ineffective or No UV Treatment UV Dose (mJ/cm2)    RUltraviolet Light Disinfection (UV) - ADWG 6 2011 version 4.0 Updated June 2025, Table IS1.71

mJ/cm2

B

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LRV

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5. Chemical Disinfection RChemical Disinfection - USEPA Disinfection Profiling and Benchmarking Guidance Manual, Aug 1999/USEPA Disinfection Profiling and Benchmarking Technical Guidance Manual, Jun 2020. ADWG 6 2011 version 4.0 Updated June 2025, table 5.6

Disinfectant

Please Choose Chlorine Chloramine

Disinfectant residual at CWS outlet

Please Choose 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0   mg/L

Minimum water temperature

Please Choose 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25  º C

pH

Please Choose 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5

Clear Water Storage Capacity

ML

Minimum operating level

%

Baffle factor of CWS

Choose 0.1 0.3 0.5 0.7 1.0

Peak outflow rate

L/sec

Outlet water main diameter

mm

Water main length to first customer

m

Pipe Volume

m3     L

Contact Time in Tank

min    hr

Contact Time in Pipe

min    hr

Total Contact Time

min    hr

B

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Total CT

mg.min/L

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B

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Overall Log Removal Achieved

Total Log Removal Required

Further Log Removal Required

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