US GYPSUM COMPANY

NPDES permit IN0003646 · Minor NON-POTW · effective, expires 2028-02-29 · EPA's file as of 2026-09-19

Check this month's numbers before you file
Watch this permit — $79 a month. Every Monday, from EPA's newest files: the next report due and when, whether EPA's file holds your last one, any change to this permit's limits or status, and the renewal date.

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

1values over a limit
1required values missing, on 1 form(s)
1of 59 forms filed late

Last period with anything received: 2026-07-31. Most often over: Sulfate, total [as SO4] (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 (138)

OutfallParameterStatisticLimitMonths
001Oxygen, dissolved [DO]DLYAVMIN >= 5 mg/L May, Jun, Jul, Aug, Sep, Oct, Nov
001Oxygen, dissolved [DO]DLYAVMIN >= 6 mg/L Jan, Feb, Mar, Apr, Dec
001pHDAILY MN >= 6 SU all year
001pHDAILY MX <= 9 SU all year
001Solids, total suspendedMO AVG <= 20 mg/L all year
001Solids, total suspendedDAILY MX <= 30 mg/L all year
001Solids, total suspendedMO AVG <= 6.7 lb/d all year
001Solids, total suspendedDAILY MX <= 10 lb/d all year
001Oil and grease, hexane extr methodMO AVG <= 10 mg/L all year
001Oil and grease, hexane extr methodDAILY MX <= 15 mg/L all year
001Nitrogen, ammonia total [as N]MO AVG <= 3 mg/L Jan, Feb, Mar, Apr, Dec
001Nitrogen, ammonia total [as N]MO AVG <= 1.5 mg/L May, Jun, Jul, Aug, Sep, Oct, Nov
001Nitrogen, ammonia total [as N]DAILY MX <= 6 mg/L Jan, Feb, Mar, Apr, Dec
001Nitrogen, ammonia total [as N]DAILY MX <= 3 mg/L May, Jun, Jul, Aug, Sep, Oct, Nov
001Nitrogen, ammonia total [as N]MO AVG <= .5 lb/d Jan, Feb, Mar, Apr, Dec
001Nitrogen, ammonia total [as N]MO AVG <= 1 lb/d May, Jun, Jul, Aug, Sep, Oct, Nov
001Nitrogen, ammonia total [as N]DAILY MX <= 1 lb/d Jan, Feb, Mar, Apr, Dec
001Nitrogen, ammonia total [as N]DAILY MX <= 2 lb/d May, Jun, Jul, Aug, Sep, Oct, Nov
001Hardness, total [as CaCO3]MO AVG report only all year
001Hardness, total [as CaCO3]DAILY MX report only all year
001Chloride [as Cl]MO AVG report only all year
001Chloride [as Cl]DAILY MX report only all year
001Sulfate, total [as SO4]MO AVG <= 2300 mg/L all year
001Sulfate, total [as SO4]DAILY MX <= 3950 mg/L all year
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantDAILY MX report only 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
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 10 mg/L all year
001BOD, carbonaceous [5 day, 20 C]DAILY MX <= 15 mg/L all year
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 3.3 lb/d all year
001BOD, carbonaceous [5 day, 20 C]DAILY MX <= 5 lb/d all year
001Flow, totalMO TOTAL report only all year
002StreamflowMO AVG report only all year
002StreamflowDAILY MX report only all year
002pHDAILY MN >= 6 SU all year
002pHDAILY MN >= 6 SU all year
002pHDAILY MX <= 9 SU all year
002pHDAILY MX <= 9 SU all year
002Solids, total suspendedMO AVG <= 20 mg/L all year
002Solids, total suspendedMO AVG <= 20 mg/L all year
002Solids, total suspendedDAILY MX <= 30 mg/L all year
002Solids, total suspendedDAILY MX <= 30 mg/L all year
002Oil and grease, hexane extr methodMO AVG <= 10 mg/L all year
002Oil and grease, hexane extr methodMO AVG <= 10 mg/L all year
002Oil and grease, hexane extr methodDAILY MX <= 15 mg/L all year
002Oil and grease, hexane extr methodDAILY MX <= 15 mg/L all year
002Hardness, total [as CaCO3]MO AVG report only all year
002Hardness, total [as CaCO3]MO AVG report only all year
002Hardness, total [as CaCO3]DAILY MX report only all year
002Hardness, total [as CaCO3]DAILY MX report only all year
002Chloride [as Cl]MO AVG <= 470 mg/L all year
002Chloride [as Cl]MO AVG <= 750 mg/L all year
002Chloride [as Cl]DAILY MX <= 810 mg/L all year
002Chloride [as Cl]DAILY MX <= 1300 mg/L all year
002Sulfate, total [as SO4]MO AVG <= 2300 mg/L all year
002Sulfate, total [as SO4]MO AVG <= 4500 mg/L all year
002Sulfate, total [as SO4]DAILY MX <= 3950 mg/L all year
002Sulfate, total [as SO4]DAILY MX <= 7700 mg/L all year
002Flow, in conduit or thru treatment plantMO AVG report only all year
002Flow, in conduit or thru treatment plantMO AVG report only all year
002Flow, in conduit or thru treatment plantDAILY MX report only all year
002Flow, in conduit or thru treatment plantDAILY MX report only all year
002Effluent dilution ratioDAILY MX <= .5 Ratio all year
002Flow, totalMO TOTAL report only all year
002Flow, totalMO TOTAL report only all year
003pHDAILY MN >= 6 SU all year
003pHDAILY MX <= 9 SU all year
003Solids, total suspendedMO AVG <= 20 mg/L all year
003Solids, total suspendedDAILY MX <= 30 mg/L all year
003Oil and grease, hexane extr methodMO AVG <= 10 mg/L all year
003Oil and grease, hexane extr methodDAILY MX <= 15 mg/L all year
003Hardness, total [as CaCO3]MO AVG report only all year
003Hardness, total [as CaCO3]DAILY MX report only all year
003Chloride [as Cl]MO AVG <= 470 mg/L all year
003Chloride [as Cl]DAILY MX <= 810 mg/L all year
003Sulfate, total [as SO4]MO AVG <= 2300 mg/L all year
003Sulfate, total [as SO4]DAILY MX <= 3950 mg/L all year
003Flow, in conduit or thru treatment plantMO AVG report only all year
003Flow, in conduit or thru treatment plantDAILY MX report only all year
003Flow, totalMO TOTAL report only all year
004pHDAILY MN >= 6 SU Jun, Dec
004pHDAILY MN >= 6 SU Jun, Dec
004pHDAILY MX <= 9 SU Jun, Dec
004pHDAILY MX <= 9 SU Jun, Dec
004Solids, total suspendedDAILY MX report only Jun, Dec
004Solids, total suspendedDAILY MX report only Jun, Dec
004Oil and grease, hexane extr methodDAILY MX report only Jun, Dec
004Oil and grease, hexane extr methodDAILY MX report only Jun, Dec
004Nitrogen, Kjeldahl, total [as N]DAILY MX report only Jun, Dec
004Nitrogen, Kjeldahl, total [as N]DAILY MX report only Jun, Dec
004Nitrite + Nitrate total [as N]DAILY MX report only Jun, Dec
004Nitrite + Nitrate total [as N]DAILY MX report only Jun, Dec
004Phosphorus, total [as P]DAILY MX report only Jun, Dec
004Phosphorus, total [as P]DAILY MX report only Jun, Dec
004Sulfate, total [as SO4]DAILY MX report only Jun, Dec
004Sulfate, total [as SO4]DAILY MX report only Jun, Dec
004BOD, carbonaceous [5 day, 20 C]DAILY MX report only Jun, Dec
004BOD, carbonaceous [5 day, 20 C]DAILY MX report only Jun, Dec
004Chemical Oxygen Demand [COD]DAILY MX report only Jun, Dec
004Chemical Oxygen Demand [COD]DAILY MX report only Jun, Dec
004Storm water flowDAILY MX report only Jun, Dec
004Storm water flowDAILY MX report only Jun, Dec
005pHDAILY MN >= 6 SU Jun, Dec
005pHDAILY MN >= 6 SU Jun, Dec
005pHDAILY MX <= 9 SU Jun, Dec
005pHDAILY MX <= 9 SU Jun, Dec
005Solids, total suspendedDAILY MX report only Jun, Dec
005Solids, total suspendedDAILY MX report only Jun, Dec
005Oil and grease, hexane extr methodDAILY MX report only Jun, Dec
005Oil and grease, hexane extr methodDAILY MX report only Jun, Dec
005Nitrogen, Kjeldahl, total [as N]DAILY MX report only Jun, Dec
005Nitrogen, Kjeldahl, total [as N]DAILY MX report only Jun, Dec
005Nitrite + Nitrate total [as N]DAILY MX report only Jun, Dec
005Nitrite + Nitrate total [as N]DAILY MX report only Jun, Dec
005Phosphorus, total [as P]DAILY MX report only Jun, Dec
005Phosphorus, total [as P]DAILY MX report only Jun, Dec
005Sulfate, total [as SO4]DAILY MX report only Jun, Dec
005Sulfate, total [as SO4]DAILY MX report only Jun, Dec
005BOD, carbonaceous [5 day, 20 C]DAILY MX report only Jun, Dec
005BOD, carbonaceous [5 day, 20 C]DAILY MX report only Jun, Dec
005Chemical Oxygen Demand [COD]DAILY MX report only Jun, Dec
005Chemical Oxygen Demand [COD]DAILY MX report only Jun, Dec
005Storm water flowDAILY MX report only Jun, Dec
005Storm water flowDAILY MX report only Jun, Dec
007pHDAILY MN >= 6 SU all year
007pHDAILY MX <= 9 SU all year
007Solids, total suspendedMO AVG <= 20 mg/L all year
007Solids, total suspendedDAILY MX <= 40 mg/L all year
007Hardness, total [as CaCO3]MO AVG report only all year
007Hardness, total [as CaCO3]DAILY MX report only all year
007Chloride [as Cl]MO AVG report only all year
007Chloride [as Cl]DAILY MX report only all year
007Sulfate, total [as SO4]MO AVG report only all year
007Sulfate, total [as SO4]DAILY MX report only all year
007Flow, in conduit or thru treatment plantMO AVG report only all year
007Flow, in conduit or thru treatment plantDAILY MX report only all year
007Flow, 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