O-N Minerals (Michigan) Company

NPDES permit MI0004111 · Major NON-POTW · effective, expires 2026-10-01 · 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

0values over a limit
1required values missing, on 1 form(s)
2of 55 forms filed late

Last period with anything received: 2026-07-31.

Reporting

Reports are due about 21 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (54)

OutfallParameterStatisticLimitMonths
003pHDAILY MN >= 6.5 SU all year
003pHDAILY MX <= 9 SU all year
003Solids, total suspendedMO AVG <= 30 mg/L all year
003Solids, total suspendedDAILY MX <= 45 mg/L all year
003Chloride [as Cl]DAILY MX report only all year
003Sulfate, total [as SO4]DAILY MX report only 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
003Solids, total dissolvedDAILY MX report only all year
003Outfall observation,visual, y/n responseVALUE report only all year
004Temperature, water deg. fahrenheitMO AVG report only all year
004Temperature, water deg. fahrenheitDAILY MX report only all year
004pHDAILY MN >= 6.5 SU all year
004pHDAILY MX <= 9 SU all year
004Chloride [as Cl]DAILY MX report only all year
004Sulfate, total [as SO4]DAILY MX report only all year
004Flow, in conduit or thru treatment plantMO AVG report only all year
004Flow, in conduit or thru treatment plantDAILY MX report only all year
004Solids, total dissolvedDAILY MX report only all year
004Outfall observation,visual, y/n responseVALUE report only all year
005pHDAILY MN >= 6.5 SU all year
005pHDAILY MX <= 9 SU all year
005Solids, total suspendedMO AVG <= 30 mg/L all year
005Solids, total suspendedDAILY MX <= 45 mg/L all year
005Chloride [as Cl]DAILY MX report only all year
005Sulfate, total [as SO4]DAILY MX report only all year
005Flow, in conduit or thru treatment plantMO AVG report only all year
005Flow, in conduit or thru treatment plantDAILY MX report only all year
005Solids, total dissolvedMO AVG <= 500 mg/L all year
005Solids, total dissolvedDAILY MX <= 750 mg/L all year
005Solids, total dissolvedMO AVG <= 8700 lb/d all year
005Solids, total dissolvedDAILY MX <= 13000 lb/d all year
005Outfall observation,visual, y/n responseVALUE report only all year
006pHDAILY MN >= 6.5 SU all year
006pHDAILY MX <= 9 SU all year
006Solids, total suspendedMO AVG <= 30 mg/L all year
006Solids, total suspendedDAILY MX <= 45 mg/L all year
006Chloride [as Cl]DAILY MX report only all year
006Sulfate, total [as SO4]DAILY MX report only all year
006Flow, in conduit or thru treatment plantMO AVG report only all year
006Flow, in conduit or thru treatment plantDAILY MX report only all year
006Solids, total dissolvedDAILY MX report only all year
006Outfall observation,visual, y/n responseVALUE report only all year
007pHDAILY MN >= 6.5 SU all year
007pHDAILY MX <= 9 SU all year
007Solids, total suspendedMO AVG <= 30 mg/L all year
007Solids, total suspendedDAILY MX <= 45 mg/L all year
007Chloride [as Cl]DAILY MX 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
007Solids, total dissolvedDAILY MX report only all year
007Solids, total dissolvedDAILY MX report only all year
007Outfall observation,visual, y/n responseVALUE 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