MT. AIRY WWTP

NPDES permit MD0022527 · Major POTW · expired, expires 2025-12-31 · 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.

This permit expired on 2025-12-31 and is expired: its last limits keep applying until a new permit is issued, and EPA still expects the reports.

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

0values over a limit
0required values missing, on 0 form(s)
4of 23 forms filed late

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

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 (62)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. fahrenheitMAXIMUM report only all year
001Temperature, water deg. fahrenheitMAXIMUM report only all year
001Temperature, water deg. fahrenheitMAXIMUM report only all year
001Oxygen, dissolved [DO]INST MIN >= 5 mg/L all year
001Oxygen, dissolved [DO]DLYAVMIN >= 6 mg/L all year
001BOD, 5-day, 20 deg. CMX MO AV <= 10 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX MO AV <= 30 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMX WK AV <= 15 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX WK AV <= 45 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMX MO AV <= 100 lb/d May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX MO AV <= 300 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMX WK AV <= 150 lb/d May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX WK AV <= 450 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001pHMINIMUM >= 6.5 SU all year
001pHMAXIMUM <= 8.5 SU all year
001Solids, total suspendedMX MO AV <= 30 mg/L all year
001Solids, total suspendedMX WK AV <= 45 mg/L all year
001Solids, total suspendedMX MO AV <= 300 lb/d all year
001Solids, total suspendedANNL MAX <= 109640 lb/yr all year
001Solids, total suspendedMX WK AV <= 450 lb/d all year
001Solids, total suspendedMO TOTAL report only all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]ANNL MAX <= 14619 lb/yr all year
001Nitrogen, total [as N]ANNL TOT report only all year
001Nitrogen, total [as N]MO TOTAL report only all year
001Nitrogen, organic total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]MX DA AV <= 4.2 mg/L May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]MX DA AV <= 7.2 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]MX MO AV <= 2.6 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]MX MO AV <= 1.2 mg/L May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]MX DA AV <= 72 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]MX DA AV <= 42 lb/d May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]MX MO AV <= 12 lb/d May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]MX MO AV <= 26 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, Kjeldahl, total [as N]WKLY AVG report only Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, Kjeldahl, total [as N]MX WK AV <= 4.5 mg/L May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, Kjeldahl, total [as N]MX MO AV <= 3 mg/L May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, Kjeldahl, total [as N]MO AVG report only Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, Kjeldahl, total [as N]MX MO AV <= 30 lb/d May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, Kjeldahl, total [as N]WKLY AVG report only Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, Kjeldahl, total [as N]MX WK AV <= 45 lb/d May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, Kjeldahl, total [as N]MO AV MN report only Jan, Feb, Mar, Apr, Nov, Dec
001Nitrite + Nitrate total [as N]MO AVG report only all year
001Nitrite + Nitrate total [as N]MY report only all year
001Phosphorus, total [as P]MO AVG report only all year
001Phosphorus, total [as P]ANNL MAX <= 1096 lb/yr all year
001Phosphorus, total [as P]MO TOTAL report only all year
001Phosphorus, total [as P]ANNL TOT report only all year
001Hardness, total [as CaCO3]MAXIMUM report only 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. coliGX <= 126 MPN/100mL all year
001Phosphorous, in total orthophosphateMO AVG report only all year
001Flow, totalMO TOTAL report only all year
001Flow, totalANNL TOT report only all year
TRADSolids, total suspendedCUM TOTL report only all year
TRADSolids, total suspendedCUM TOTL report only all year
TRADNitrogen, total [as N]CUM TOTL report only all year
TRADNitrogen, total [as N]CUM TOTL report only all year
TRADPhosphorus, total [as P]CUM TOTL report only all year
TRADPhosphorus, total [as P]CUM TOTL report only all year
TRADFlowYA 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