CITY OF FAIRFAX — NPDES permit IA0030694: limits, due date and EPA's record

NPDES permit IA0030694 · Minor POTW · effective, expires 2030-04-30 · EPA's file as of 2026-09-19

EPA's record, 2025-09-01 to 2026-08-31

Reporting

Reports are due about 15 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (78)

Outfall	Parameter	Statistic	Limit	Months
002	Oxygen, dissolved [DO]	DAILY MN	>= 4 mg/L	all year
002	BOD, 5-day, 20 deg. C	30DA AVG	report only	all year
002	BOD, 5-day, 20 deg. C	DAILY MX	report only	all year
002	BOD, 5-day, 20 deg. C	30DA AVG	report only	all year
002	BOD, 5-day, 20 deg. C	DAILY MX	report only	all year
002	pH	DAILY MN	>= 6.5 SU	all year
002	pH	DAILY MX	<= 9 SU	all year
002	pH	30DA AVG	report only	all year
002	pH	DAILY MX	report only	all year
002	Solids, total suspended	30DA AVG	<= 30 mg/L	all year
002	Solids, total suspended	7 DA AVG	<= 45 mg/L	all year
002	Solids, total suspended	30DA AVG	<= 150 lb/d	all year
002	Solids, total suspended	7 DA AVG	<= 225 lb/d	all year
002	Solids, total suspended	30DA AVG	report only	all year
002	Solids, total suspended	DAILY MX	report only	all year
002	Solids, total suspended	30DA AVG	report only	all year
002	Solids, total suspended	DAILY MX	report only	all year
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 2.3 mg/L	Jul
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 5.3 mg/L	Oct
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 2.3 mg/L	Jun
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 3.9 mg/L	Apr
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 3.4 mg/L	May
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 10.6 mg/L	Jan
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 2.6 mg/L	Sep
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 6.8 mg/L	Nov
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 2.1 mg/L	Aug
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 12 mg/L	Feb
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 7.9 mg/L	Dec
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 9.2 mg/L	Mar
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 9.7 mg/L	Jul
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 15.9 mg/L	Oct
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 12.7 mg/L	Jun
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 15.9 mg/L	Apr
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 15.4 mg/L	May
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 15.5 mg/L	Jan
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 12.3 mg/L	Sep
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 14.9 mg/L	Nov
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 9.8 mg/L	Aug
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 14.6 mg/L	Feb
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 16.2 mg/L	Dec
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 14.9 mg/L	Mar
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 13 lb/d	Jul
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 20.3 lb/d	Oct
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 13.3 lb/d	Jun
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 19.8 lb/d	Apr
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 19.5 lb/d	May
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 44.6 lb/d	Jan
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 13.7 lb/d	Sep
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 30.3 lb/d	Nov
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 12.4 lb/d	Aug
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 51.3 lb/d	Feb
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 32.3 lb/d	Dec
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 43.8 lb/d	Mar
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 40 lb/d	Jul
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 79.3 lb/d	Oct
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 51.5 lb/d	Jun
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 79.2 lb/d	Apr
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 76.7 lb/d	May
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 77 lb/d	Jan
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 47.5 lb/d	Sep
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 74.1 lb/d	Nov
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 40.5 lb/d	Aug
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 72.2 lb/d	Feb
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 80.6 lb/d	Dec
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 74.4 lb/d	Mar
002	Nitrogen, Kjeldahl, total [as N]	30DA AVG	report only	all year
002	Nitrogen, Kjeldahl, total [as N]	DAILY MX	report only	all year
002	Nitrogen, Kjeldahl, total [as N]	30DA AVG	report only	all year
002	Nitrogen, Kjeldahl, total [as N]	DAILY MX	report only	all year
002	Chloride [as Cl]	30DA AVG	<= 535 mg/L	all year
002	Chloride [as Cl]	DAILY MX	<= 644 mg/L	all year
002	Chloride [as Cl]	30DA AVG	<= 2432 lb/d	all year
002	Chloride [as Cl]	DAILY MX	<= 3196 lb/d	all year
002	E. coli	GEO MEAN	<= 126 #/100mL	Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov
002	BOD, carbonaceous [5 day, 20 C]	30DA AVG	<= 25 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 40 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	30DA AVG	<= 125 lb/d	all year
002	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 200 lb/d	all year