National Park Service, Assateague Island National Seashore

NPDES permit MD0021091 · Minor FEDERAL · expired, expires 2024-10-31 · 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 2024-10-31 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

8values over a limit
10required values missing, on 1 form(s)
2of 12 forms filed late

Last period with anything received: 2026-08-31. Most often over: Phosphorus, total [as P] (3), Solids, total suspended (3), pH (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 (34)

OutfallParameterStatisticLimitMonths
001Oxygen, dissolved [DO]INST MIN >= 5 mg/L all year
001BOD, 5-day, 20 deg. CMX MO AV <= 10 mg/L all year
001BOD, 5-day, 20 deg. CMX WK AV <= 15 mg/L all year
001BOD, 5-day, 20 deg. CMX MO AV <= 1 lb/d all year
001BOD, 5-day, 20 deg. CMX WK AV <= 1.5 lb/d all year
001pHMINIMUM >= 6.5 SU all year
001pHMAXIMUM <= 8.5 SU all year
001Solids, total suspendedMX MO AV <= 10 mg/L all year
001Solids, total suspendedMX WK AV <= 15 mg/L all year
001Solids, total suspendedMX MO AV <= 1 lb/d all year
001Solids, total suspendedMX WK AV <= 1.5 lb/d all year
001Nitrogen, total [as N]MX MO AV <= 3 mg/L all year
001Nitrogen, total [as N]MX WK AV <= 4.5 mg/L all year
001Nitrogen, total [as N]MX MO AV <= .3 lb/d all year
001Nitrogen, total [as N]MX WK AV <= .45 lb/d all year
001Nitrogen, total [as N]MO TOTAL report only all year
001Nitrogen, total [as N]ANNL MAX <= 110 lb/yr all year
001Nitrogen, total [as N]CUM TOTL <= 55 lb/yr May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, organic total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]MO AVG report only all year
001Nitrite + Nitrate total [as N]MO AVG report only all year
001Phosphorus, total [as P]MX MO AV <= .3 mg/L all year
001Phosphorus, total [as P]MX WK AV <= .45 mg/L all year
001Phosphorus, total [as P]MX MO AV <= .03 lb/d all year
001Phosphorus, total [as P]MX WK AV <= .045 lb/d all year
001Phosphorus, total [as P]MO TOTAL report only all year
001Phosphorus, total [as P]ANNL MAX <= 11 lb/yr all year
001Phosphorus, total [as P]CUM TOTL <= 6 lb/yr May, Jun, Jul, Aug, Sep, Oct
001Phosphate, ortho [as P]MO AVG 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
001Chlorine, total residualMAXIMUM <= .1 mg/L all year
001Coliform, fecal generalMO MED <= 14 MPN/100mL all year
001Flow, 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