Sewage Treatment in Campus for Recycling Purpose: A Review
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Table 6
Suggested guidelines for water reuse by US EPA
Reuse category and description
Treatment
Reclaimed water quality
Unrestricted
The use of reclaimed water in nonpotable applications in municipal settings where
public access is not restricted.
Secondary
Filtration
Disinfection
pH
= 6.0–9.0
≤10 mg/L
≤2 NTU
No detectable fecal coliform/100 mL
1 mg/L Cl2 residual (min.)
Restricted
The use of reclaimed water in nonpotable applications in municipal settings where
public access is controlled or restricted by physical or institutional barriers, such as
fencing, advisory signage, or temporal access restriction
Secondary
Disinfection
pH
= 6.0–9.0
≤30 mg/L
≤30 mg/l TSS
≤200 fecal coliform/100 ml
1 mg/L Cl2 residual (min.)
Food crops
The use of reclaimed water for surface or spray irrigation of food crops which are
intended for human consumption, consumed raw.
Secondary
Filtration
Disinfection
pH
= 6.0-9.0
≤10 mg/l BOD
≤2 NTU
No detectable fecal coliform/100 ml
1 mg/l Cl2 residual (min.)
Processed food crops
The use of reclaimed water for surface irrigation of food crops which are intended
for human consumption, commercially processed.
Non-food crops
The use of reclaimed water for irrigation of crops which are not consumed by
humans, including fodder, fiber, and seed crops, or to irrigate pasture land,
commercial nurseries, and sod farms.
Secondary
Disinfection
pH
= 6.0-9.0
≤30 mg/l BOD (7)
≤30 mg/l TSS
≤200 fecal coli/100 ml
1 mg/l Cl2 residual (min.)
Environmental reuse
The use of reclaimed water to create wetlands, enhance natural wetlands, or sustain
stream flows.
Variable
Secondary (and disinfection
(min.)
Variable, but not to exceed:
≤30 mg/l BOD
≤30 mg/l TSS
≤200 fecal coliform/100 ml
1 mg/l Cl2 residual (min.)
(continued)