TOWN OF GRASS RANGE

NPDES permit MT0030309 · Minor POTW · effective, expires 2026-09-30 · 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
0required values missing, on 0 form(s)
0of 16 forms filed late

Last period with anything received: 2026-08-31.

Reporting

Reports are due about 28 days after each monitoring period ends (the most common figure among MT permits in EPA's filings — check your permit).

Limits in force (32)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. centigradeSINGSAMP report only all year
001Flow rateMO AVG report only all year
001Flow rateDAILY MX report only all year
001BOD, 5-day, 20 deg. CMO AVG <= 30 mg/L all year
001BOD, 5-day, 20 deg. CMX WK AV <= 45 mg/L all year
001BOD, 5-day, 20 deg. CMO AVG <= 9.5 lb/d all year
001BOD, 5-day, 20 deg. CMX WK AV <= 14.3 lb/d all year
001BOD, 5-day, 20 deg. CMO AVG report only all year
001pHDAILY MN >= 6 SU all year
001pHDAILY MX <= 9 SU all year
001pHSINGSAMP report only 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 <= 9.5 lb/d all year
001Solids, total suspendedMX WK AV <= 14.3 lb/d all year
001Solids, total suspendedMO AVG report only all year
001Oil and grease, hexane extr methodDAILY MX <= 10 mg/L all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]DAILY MX report only all year
001Nitrogen, ammonia total [as N]SINGSAMP report only all year
001Nitrogen, Kjeldahl, total [as N]MO AVG report only all year
001Nitrite + Nitrate total [as N]MO AVG report only all year
001Phosphorus, total [as P]MO AVG report only all year
001E. coli, MTEC-MFMOAV GEO <= 126 #/100mL Apr, May, Jun, Jul, Aug, Sep, Oct
001E. coli, MTEC-MFMOAV GEO <= 630 #/100mL Jan, Feb, Mar, Nov, Dec
001E. coli, MTEC-MFMV <= 252 #/100mL Apr, May, Jun, Jul, Aug, Sep, Oct
001E. coli, MTEC-MFMV <= 1260 #/100mL Jan, Feb, Mar, Nov, Dec
001BOD, 5-day, percent removalMINIMUM >= 85 % all year
001Solids, suspended percent removalMINIMUM >= 85 % all year
001Duration of dischargeMO TOTAL report only all year
001Oil and grease visualVALUE 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