STILLWATER MINING COMPANY

NPDES permit MT0026808 · Minor NON-POTW · effective, expires 2028-08-31 · 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

2values over a limit
0required values missing, on 0 form(s)
0of 81 forms filed late

Last period with anything received: 2026-07-31. Most often over: Mercury, total recoverable (2).

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 (145)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. fahrenheitDAILY MX report only all year
001Flow rateMO AVG report only all year
001Flow rateDAILY MX report only all year
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
001Nitrogen, total [as N]MO AVG report only Jul, Aug, Sep
001Nitrogen, ammonia total [as N]MO AVG <= .53 mg/L all year
001Nitrogen, ammonia total [as N]DAILY MX <= 1.94 mg/L all year
001Nitrogen, Kjeldahl, total [as N]MO AVG report only Jul, Aug, Sep
001Nitrite + Nitrate total [as N]MO AVG report only Jul, Aug, Sep
001Nitrite + Nitrate total [as N]DAILY MX report only Jul, Aug, Sep
001Phosphorus, total [as P]MO AVG report only Jul, Aug, Sep
001Phosphorus, total [as P]MO AVG <= .6 lb/d Jul, Aug, Sep
001Iron, total recoverableMO AVG report only all year
001Iron, total recoverableDAILY MX report only all year
001Nickel, total recoverableMO AVG <= 22 ug/L all year
001Nickel, total recoverableDAILY MX <= 13 ug/L all year
001Zinc, total recoverableMO AVG <= 15 ug/L all year
001Zinc, total recoverableDAILY MX <= 29 ug/L all year
001Aluminum, dissolved [as Al]MO AVG report only all year
001Aluminum, dissolved [as Al]DAILY MX report only all year
001Cadmium, total recoverableMO AVG <= .23 ug/L all year
001Cadmium, total recoverableDAILY MX <= .23 ug/L all year
001Lead, total recoverableMO AVG <= .7 ug/L all year
001Lead, total recoverableDAILY MX <= .7 ug/L all year
001Chromium, total recoverableVALUE report only all year
001Copper, total recoverableMO AVG <= .49 ug/L all year
001Copper, total recoverableDAILY MX <= .93 ug/L all year
001Antimony, total recoverableVALUE report only all year
001Mercury, total recoverableMO AVG <= .005 ug/L all year
001Mercury, total recoverableDAILY MX <= .005 ug/L all year
001Pass/Fail Static Renewal 7 Day Chronic Ceriodaphnia dubiaVALUE <= 0 pass=0;fail=1 all year
001Pass/Fail Static Renewal 7Day Chronic Pimephales promelasVALUE <= 0 pass=0;fail=1 all year
002Flow rateMO AVG report only all year
002Flow rateDAILY MX report only all year
002pHDAILY MN >= 6 SU all year
002pHDAILY MX <= 9 SU all year
002Nitrogen, total [as N]MO AVG report only all year
002Nitrogen, total [as N]MO AVG report only all year
002Nitrogen, Kjeldahl, total [as N]MO AVG report only all year
002Nitrite + Nitrate total [as N]MO AVG report only all year
002Phosphorus, total [as P]MO AVG report only all year
002Phosphorus, total [as P]MO AVG report only all year
002Iron, total recoverableMO AVG report only all year
002Nickel, total recoverableMO AVG report only all year
002Zinc, total recoverableMO AVG <= 24 ug/L all year
002Zinc, total recoverableDAILY MX <= 48 ug/L all year
002Antimony, dissolved [as Sb]MO AVG report only all year
002Aluminum, dissolved [as Al]MO AVG report only all year
002Cadmium, total recoverableMO AVG <= .5 ug/L all year
002Cadmium, total recoverableDAILY MX <= .5 ug/L all year
002Lead, total recoverableMO AVG <= 1.1 ug/L all year
002Lead, total recoverableDAILY MX <= 1.1 ug/L all year
002Chromium, total recoverableMO AVG report only all year
002Copper, total recoverableMO AVG report only all year
002Mercury, total recoverableMO AVG <= .005 ug/L all year
002Mercury, total recoverableDAILY MX <= .005 ug/L all year
003Flow rateQRTR AVG report only all year
003Flow rateMO MAX report only all year
003BOD, 5-day, 20 deg. CQRTR AVG report only all year
003pHQC report only all year
003pHQB report only all year
003pHQRTR AVG report only all year
003Solids, total suspendedQRTR AVG report only all year
003Nitrogen, total [as N]QRTR AVG report only all year
003Nitrogen, total [as N]QRTR AVG report only all year
003Nitrogen, total [as N]QRTR AVG report only all year
003Nitrogen, ammonia total [as N]QRTR AVG report only all year
003Nitrogen, Kjeldahl, total [as N]QRTR AVG report only all year
003Nitrite + Nitrate total [as N]QRTR AVG report only all year
003Nitrite + Nitrate total [as N]QRTR AVG report only all year
003Phosphorus, total [as P]QRTR AVG report only all year
003Phosphorus, total [as P]QRTR AVG report only all year
003Phosphorus, total [as P]QRTR AVG report only all year
003Iron, total recoverableQRTR AVG report only all year
003Nickel, total recoverableQRTR AVG report only all year
003Zinc, total recoverableQRTR AVG report only all year
003Aluminum, dissolved [as Al]QRTR AVG report only all year
003Cadmium, total recoverableQRTR AVG report only all year
003Lead, total recoverableQRTR AVG report only all year
003Lead, total recoverableQRTR AVG report only all year
003Chromium, total recoverableQRTR AVG report only all year
003Copper, total recoverableQRTR AVG report only all year
003Copper, total recoverableQRTR AVG report only all year
003Antimony, total recoverableQRTR AVG report only all year
003Mercury, total recoverableQRTR AVG report only all year
003Mercury, total recoverableQRTR AVG report only all year
MW2Specific conductanceDAILY MX report only all year
MW2pHDAILY MX report only all year
MW2Nitrogen, total [as N]DAILY MX report only all year
MW2Nitrogen, ammonia total [as N]DAILY MX report only all year
MW2Nitrite + Nitrate total [as N]DAILY MX report only all year
MW2Water level at sample collection timeDAILY MX report only all year
MW3Specific conductanceDAILY MX report only all year
MW3pHDAILY MX report only all year
MW3Nitrogen, total [as N]DAILY MX report only all year
MW3Nitrogen, ammonia total [as N]DAILY MX report only all year
MW3Nitrite + Nitrate total [as N]DAILY MX report only all year
MW3Water level at sample collection timeDAILY MX report only all year
MW6Specific conductanceDAILY MX report only all year
MW6pHDAILY MX report only all year
MW6Nitrogen, total [as N]DAILY MX report only all year
MW6Nitrogen, ammonia total [as N]DAILY MX report only all year
MW6Nitrite + Nitrate total [as N]DAILY MX report only all year
MW6Water level at sample collection timeDAILY MX report only all year
MW7ASpecific conductanceDAILY MX report only all year
MW7ApHDAILY MX report only all year
MW7ANitrogen, total [as N]DAILY MX report only all year
MW7ANitrogen, ammonia total [as N]DAILY MX report only all year
MW7ANitrite + Nitrate total [as N]DAILY MX report only all year
MW7AWater level at sample collection timeDAILY MX report only all year
MW8Specific conductanceDAILY MX report only all year
MW8pHDAILY MX report only all year
MW8Nitrogen, total [as N]DAILY MX report only all year
MW8Nitrogen, ammonia total [as N]DAILY MX report only all year
MW8Nitrite + Nitrate total [as N]DAILY MX report only all year
MW8Water level at sample collection timeDAILY MX report only all year
MW9Specific conductanceDAILY MX report only all year
MW9pHDAILY MX report only all year
MW9Nitrogen, total [as N]DAILY MX report only all year
MW9Nitrogen, ammonia total [as N]DAILY MX report only all year
MW9Nitrite + Nitrate total [as N]DAILY MX report only all year
MW9Water level at sample collection timeDAILY MX report only all year
SUMNitrogen, total [as N]MO AVG <= 15.1 lb/d all year
SUMIron, total recoverableMO AVG <= 28.5 lb/d all year
SUMLead, total recoverableMO AVG <= .005 lb/d all year
SUMCopper, total recoverableMO AVG <= .061 lb/d all year
WW1Specific conductanceQRTR AVG report only all year
WW1pHQRTR AVG report only all year
WW1Nitrogen, total [as N]QRTR AVG report only all year
WW1Nitrogen, ammonia total [as N]QRTR AVG report only all year
WW1Nitrite + Nitrate total [as N]QRTR AVG report only all year
WW1Iron, total recoverableQRTR AVG report only all year
WW1Nickel, total recoverableQRTR AVG report only all year
WW1Zinc, total recoverableQRTR AVG report only all year
WW1Antimony, dissolved [as Sb]QRTR AVG report only all year
WW1Aluminum, dissolved [as Al]QRTR AVG report only all year
WW1Cadmium, total recoverableQRTR AVG report only all year
WW1Lead, total recoverableQRTR AVG report only all year
WW1Chromium, total recoverableQRTR AVG report only all year
WW1Copper, total recoverableQRTR AVG report only all year
WW1Mercury, total recoverableQRTR AVG report only all year
WW1Water level at sample collection timeQRTR AVG 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