GENON HOLDCO 10, LLC

NPDES permit MA0004928 · Major NON-POTW · administratively continued, expires 1994-06-23 · 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 1994-06-23 and is administratively continued: 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

1values over a limit
0required values missing, on 0 form(s)
0of 60 forms filed late

Last period with anything received: 2026-08-31. Most often over: Temperature, water deg. fahrenheit (1).

Reporting

Reports are due about 15 days after each monitoring period ends (the most common figure among MA permits in EPA's filings — check your permit).

Limits in force (35)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. fahrenheitDAILY MX <= 86 deg F all year
001pHMINIMUM >= 6.5 SU all year
001pHMAXIMUM <= 8.5 SU all year
001Flow, in conduit or thru treatment plantDAILY MX <= 518 MGD all year
001Chlorine, total residualDAILY MX <= .1 mg/L all year
002Temperature, water deg. fahrenheitDAILY MX <= 90 deg F all year
002pHMINIMUM >= 6.5 SU all year
002pHMAXIMUM <= 8.5 SU all year
002Flow, in conduit or thru treatment plantMO AVG <= 2.5 MGD all year
002Flow, in conduit or thru treatment plantDAILY MX <= 4.4 MGD all year
010pHMINIMUM >= 6.5 SU all year
010pHMAXIMUM <= 8.5 SU all year
010Oil & GreaseMO AVG <= 10 mg/L all year
010Oil & GreaseDAILY MX <= 15 mg/L all year
010Flow, in conduit or thru treatment plantMO AVG <= .072 MGD all year
010Flow, in conduit or thru treatment plantDAILY MX <= .144 MGD all year
011pHMINIMUM >= 6 SU all year
011pHMAXIMUM <= 9 SU all year
011Solids, total suspendedMO AVG <= 30 mg/L all year
011Solids, total suspendedDAILY MX <= 100 mg/L all year
011Oil & GreaseMO AVG <= 10 mg/L all year
011Oil & GreaseDAILY MX <= 15 mg/L all year
011Copper, total [as Cu]MO AVG <= 1 mg/L all year
011Copper, total [as Cu]DAILY MX <= 1 mg/L all year
011Iron, total [as Fe]MO AVG <= 1 mg/L all year
011Iron, total [as Fe]DAILY MX <= 1 mg/L all year
011Flow, in conduit or thru treatment plantMO AVG <= .25 MGD all year
011Flow, in conduit or thru treatment plantDAILY MX <= .4 MGD all year
012pHMINIMUM >= 6.5 SU all year
012pHMAXIMUM <= 8.5 SU all year
012Solids, total suspendedMO AVG <= 30 mg/L all year
012Solids, total suspendedDAILY MX <= 100 mg/L all year
012Oil & GreaseDAILY MX <= 15 mg/L all year
012Flow, in conduit or thru treatment plantMO AVG <= .07 MGD all year
012Flow, in conduit or thru treatment plantDAILY MX <= .12 MGD 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