OAK PARK CONSERVANCY DISTRICT

NPDES permit IN0023965 · Major POTW · effective, expires 2028-03-31 · EPA's file as of 2026-09-19

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

1values over a limit
0required values missing, on 0 form(s)
8of 22 forms filed late

Last period with anything received: 2026-07-31. Most often over: Phosphorus, total [as P] (1).

Reporting

Reports are due about 28 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (66)

OutfallParameterStatisticLimitMonths
001pHDAILY MN >= 6 SU all year
001pHDAILY MX <= 9 SU all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedMX WK AV <= 45 mg/L all year
001Solids, total suspendedMO AVG <= 307.9 lb/d all year
001Solids, total suspendedMX WK AV <= 461.9 lb/d all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]MO AVG <= 3 mg/L May, Jun, Jul, Aug, Sep, Oct, Nov
001Nitrogen, ammonia total [as N]MO AVG <= 9.6 mg/L Jan, Feb, Mar, Apr, Dec
001Nitrogen, ammonia total [as N]MX WK AV <= 4.5 mg/L May, Jun, Jul, Aug, Sep, Oct, Nov
001Nitrogen, ammonia total [as N]MX WK AV <= 14.4 mg/L Jan, Feb, Mar, Apr, Dec
001Nitrogen, ammonia total [as N]MO AVG <= 31 lb/d May, Jun, Jul, Aug, Sep, Oct, Nov
001Nitrogen, ammonia total [as N]MO AVG <= 100 lb/d Jan, Feb, Mar, Apr, Dec
001Nitrogen, ammonia total [as N]MX WK AV <= 46.5 lb/d May, Jun, Jul, Aug, Sep, Oct, Nov
001Nitrogen, ammonia total [as N]MX WK AV <= 150 lb/d Jan, Feb, Mar, Apr, Dec
001Nitrogen, Kjeldahl, total [as N]DAILY MX report only all year
001Nitrogen, Kjeldahl, total [as N]DAILY MX report only all year
001Nitrite + Nitrate total [as N]DAILY MX report only all year
001Nitrite + Nitrate total [as N]DAILY MX report only all year
001Phosphorus, total [as P]MO AVG <= 1 mg/L all year
001Phosphorus, total [as P]MO AVG report only all year
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Chlorine, total residualMO AVG < .06 mg/L all year
001Chlorine, total residualDAILY MX < .06 mg/L all year
001E. coli, colony forming units [CFU]MO GEO <= 125 CFU/100mL Apr, May, Jun, Jul, Aug, Sep, Oct
001E. coli, colony forming units [CFU]DAILY MX <= 235 CFU/100mL Apr, May, Jun, Jul, Aug, Sep, Oct
001Coliform, fecal generalMO AVG <= 2000 #/100mL Jan, Feb, Mar, Nov, Dec
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 25 mg/L all year
001BOD, carbonaceous [5 day, 20 C]MX WK AV <= 40 mg/L all year
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 256.6 lb/d all year
001BOD, carbonaceous [5 day, 20 C]MX WK AV <= 410.6 lb/d all year
001Flow, totalMO TOTAL report only all year
002pHDAILY MN >= 6 SU all year
002pHDAILY MX <= 9 SU all year
002Solids, total suspendedMO AVG <= 30 mg/L all year
002Solids, total suspendedMX WK AV <= 45 mg/L all year
002Solids, total suspendedMO AVG <= 307.6 lb/d all year
002Solids, total suspendedMX WK AV <= 461.9 lb/d all year
002Nitrogen, total [as N]MO AVG report only all year
002Nitrogen, total [as N]MO AVG report only all year
002Nitrogen, ammonia total [as N]MO AVG <= 3 mg/L May, Jun, Jul, Aug, Sep, Oct, Nov
002Nitrogen, ammonia total [as N]MO AVG <= 9.6 mg/L Jan, Feb, Mar, Apr, Dec
002Nitrogen, ammonia total [as N]MX WK AV <= 4.5 mg/L May, Jun, Jul, Aug, Sep, Oct, Nov
002Nitrogen, ammonia total [as N]MX WK AV <= 14.4 mg/L Jan, Feb, Mar, Apr, Dec
002Nitrogen, ammonia total [as N]MO AVG <= 31 lb/d May, Jun, Jul, Aug, Sep, Oct, Nov
002Nitrogen, ammonia total [as N]MO AVG <= 100 lb/d Jan, Feb, Mar, Apr, Dec
002Nitrogen, ammonia total [as N]MX WK AV <= 46.5 lb/d May, Jun, Jul, Aug, Sep, Oct, Nov
002Nitrogen, ammonia total [as N]MX WK AV <= 150 lb/d Jan, Feb, Mar, Apr, Dec
002Nitrogen, Kjeldahl, total [as N]DAILY MX report only all year
002Nitrogen, Kjeldahl, total [as N]DAILY MX report only all year
002Nitrite + Nitrate total [as N]DAILY MX report only all year
002Nitrite + Nitrate total [as N]DAILY MX report only all year
002Phosphorus, total [as P]MO AVG <= 1 mg/L all year
002Phosphorus, total [as P]MO AVG report only all year
002Flow, in conduit or thru treatment plantMO AVG report only all year
002Chlorine, total residualMO AVG < .06 mg/L all year
002Chlorine, total residualDAILY MX < .06 mg/L all year
002E. coli, colony forming units [CFU]MO GEO <= 125 CFU/100mL all year
002E. coli, colony forming units [CFU]DAILY MX <= 235 CFU/100mL all year
002Coliform, fecal generalMO AVG <= 2000 #/100mL Jan, Feb, Mar, Nov, Dec
002BOD, carbonaceous [5 day, 20 C]MO AVG <= 25 mg/L all year
002BOD, carbonaceous [5 day, 20 C]MX WK AV <= 40 mg/L all year
002BOD, carbonaceous [5 day, 20 C]MO AVG <= 256.6 lb/d all year
002BOD, carbonaceous [5 day, 20 C]MX WK AV <= 410.6 lb/d all year
002Flow, totalMO TOTAL report only all year

Built from EPA's ECHO bulk files. EPA's file, not the permit document, is the source: read your permit. Check a report before you file it · All states