Excelon Generation Company,LLC- Three Mile Island Nuclear Station

NPDES permit PA0009920 · Major NON-POTW · administratively continued, expires 2012-10-31 · 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 2012-10-31 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

0values over a limit
0required values missing, on 0 form(s)
0of 96 forms filed late

Last period with anything received: 2026-06-30.

Reporting

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

Limits in force (74)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. fahrenheitDAILY MX <= 110 deg F Jan, Feb, Mar, Oct, Nov, Dec
001Temperature, water deg. fahrenheitDAILY MX <= 115 deg F Apr, May, Jun, Jul, Aug, Sep
001pHMINIMUM >= 6 SU all year
001pHMAXIMUM <= 9 SU all year
001Solids, total suspendedMO AVG report only all year
001Solids, total suspendedDAILY MX report only all year
001Oxidants, total residualDAILY MX <= .14 mg/L 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, free availableDAILY MX <= .2 mg/L all year
001Spectrus CT 1300DAILY MX <= .1 mg/L all year
001HydrazineINST MAX < .01 mg/L all year
003Temperature, water deg. fahrenheitDAILY MX <= 110 deg F Jan, Feb, Mar, Oct, Nov, Dec
003Temperature, water deg. fahrenheitDAILY MX <= 115 deg F Apr, May, Jun, Jul, Aug, Sep
003pHMINIMUM >= 6 SU all year
003pHMAXIMUM <= 9 SU all year
003Solids, total suspendedMO AVG report only all year
003Solids, total suspendedDAILY MX report only all year
003Oxidants, total residualDAILY MX <= .14 mg/L all year
003Flow, in conduit or thru treatment plantMO AVG report only all year
003Flow, in conduit or thru treatment plantDAILY MX report only all year
003Chlorine, free availableDAILY MX <= .2 mg/L all year
003Spectrus CT 1300DAILY MX <= .1 mg/L all year
003HydrazineINST MAX < .01 mg/L all year
004Temperature, water deg. fahrenheitDAILY MX report only all year
004pHMINIMUM >= 6 SU all year
004pHMAXIMUM <= 9 SU all year
004Solids, total suspendedMO AVG report only all year
004Solids, total suspendedDAILY MX report only all year
004Oxidants, total residualDAILY MX <= .14 mg/L all year
004Flow, in conduit or thru treatment plantMO AVG report only all year
004Flow, in conduit or thru treatment plantDAILY MX report only all year
004Chlorine, free availableDAILY MX <= .2 mg/L all year
004Spectrus CT 1300DAILY MX <= .1 mg/L all year
004HydrazineINST MAX < .01 mg/L all year
005pHMINIMUM >= 6 SU all year
005pHMAXIMUM <= 9 SU all year
005Solids, total suspendedMO AVG <= 30 mg/L all year
005Solids, total suspendedDAILY MX <= 100 mg/L all year
005Oil & GreaseMO AVG <= 15 mg/L all year
005Oil & GreaseDAILY MX <= 20 mg/L all year
005Flow, in conduit or thru treatment plantMO AVG report only all year
005Flow, in conduit or thru treatment plantDAILY MX report only all year
101Solids, total suspendedMO AVG <= 30 mg/L all year
101Phosphorus, total [as P]MO AVG <= 2 mg/L all year
101Flow, in conduit or thru treatment plantMO AVG report only all year
101Flow, in conduit or thru treatment plantDAILY MX report only all year
101Coliform, fecal generalGEO MEAN <= 200 #/100mL May, Jun, Jul, Aug, Sep
101Coliform, fecal generalGEO MEAN <= 2000 #/100mL Jan, Feb, Mar, Apr, Oct, Nov, Dec
101BOD, carbonaceous [5 day, 20 C]MO AVG <= 25 mg/L all year
401pHMINIMUM >= 6 SU all year
401pHMAXIMUM <= 9 SU all year
401Solids, total suspendedMO AVG <= 30 mg/L all year
401Solids, total suspendedDAILY MX <= 100 mg/L all year
401Oil & GreaseMO AVG <= 15 mg/L all year
401Oil & GreaseDAILY MX <= 20 mg/L all year
401Flow, in conduit or thru treatment plantMO AVG report only all year
401Flow, in conduit or thru treatment plantDAILY MX report only all year
501pHMINIMUM >= 6 SU all year
501pHMAXIMUM <= 9 SU all year
501Solids, total suspendedMO AVG <= 30 mg/L all year
501Solids, total suspendedDAILY MX <= 100 mg/L all year
501Oil & GreaseMO AVG <= 15 mg/L all year
501Oil & GreaseDAILY MX <= 20 mg/L all year
501Flow, in conduit or thru treatment plantMO AVG report only all year
501Flow, in conduit or thru treatment plantDAILY MX report only all year
701pHMINIMUM >= 6 SU all year
701pHMAXIMUM <= 9 SU all year
701Solids, total suspendedMO AVG <= 30 mg/L all year
701Solids, total suspendedDAILY MX <= 100 mg/L all year
701Oil & GreaseMO AVG <= 15 mg/L all year
701Oil & GreaseDAILY MX <= 20 mg/L all year
701Flow, in conduit or thru treatment plantMO AVG report only all year
701Flow, in conduit or thru treatment plantDAILY MX 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