Table 3.8 (continued) Water quality objectivesc Log Indicative treatment process Log On-site preventive measures Expo- reduction reductions sure targets achievable reduct- ionb (V, P, B)a by treatment (V, P, B) Municipal use, with restricted access and application no 1.0 <20 mg/Ld • minimum 25–30 m buffer to nearest point Secondary treatment with • • access SS <30 mg/ Ld of public access • disinfection after 1.0 Disinfectant residual (eg minimum spray drift control; for example, through • • chlorine residual) or UV dosee low-throw sprinklers (180° inward throw), 2.0–3.0 vegetation screening, or anemometer 1.0 <100 cfu/100 mL E. coli 1.0 • until switching >6.0 dry (1– 4 • 2.0 Restrict public access during irrigation and O one of the following: Municipal use, with enhanced restrictions on access and application 1.0–3.0 during irrigation and combinations of: 0 mg/Ld • Secondary treatment with >25 days • B SS <30 mg/ Ld lagoon detention or primary • Restrict 2.0 D public 1.0–3.0 <2 access treatment with >50 days lagoon 1.0 <1000 cfu/100 mL 3.0–4.0 no access after irrigation, until dry (1– E. coli • detention (disinfection may be required to 4 hours) • minimum 25–30 m buffer to nearest 1.0 this concentration) Secondary treatment 0.5–2.0 • • point of public access 0.5–1.0 1.0–3.0 spray drift control, eg through low throw • sprinklers (180° inward throw), vegetation screening, or anemometer switching 1.0
Table 3.8 (continued) Log Indicative treatment process Log On-site preventive measures Expo- Water quality objectivesc reduction reductions sure targets (V, P, B)a achievable by reduct- ionb treatment (V, P, B) Municipal use, with restricted access and application • Secondary treatment with disinfection 2.0–3.0 1.0 >6.0 Restrict public access during irrigation and one of the following: • no access after until dry (1– 4 • minimum 25–30 m buffer to nearest point of public access • spray drift control; for example, through low-throw sprinklers (180° inward throw), vegetation screening, or anemometer switching 2.0 1.0 1.0 1.0 • <20 mg/Ld • SS <30 mg/ Ld • Disinfectant residual (eg minimum chlorine residual) or UV dosee • E. coli <100 cfu/100 mL Municipal use, with enhanced restrictions on access and application • Secondary treatment with >25 days lagoon detention or primary 1.0–3.0 1.0–3.0 Restrict public access during irrigation and combinations of: 2.0 • mg/Ld • SS <30 mg/ Ld treatment with >50 days lagoon detention 3.0–4.0 • no access after irrigation, until dry (1– 4 hours) 1.0 • E. coli <1000 cfu/100 mL (disinfection may be required to • Secondary treatment 0.5–2.0 0.5–1.0 • minimum 25–30 m buffer to nearest point of public access 1.0 this concentration) 1.0–3.0 • spray drift control, eg through low throw sprinklers (180° inward throw), vegetation screening, or anemometer switching 1.0 B 0 <2 D O
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