Arkansas Electric Cooperative Corporation - Harry L. Oswald Generating Station

NPDES permit AR0049255 · Major NON-POTW · effective, expires 2028-02-29 · 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

1values over a limit
0required values missing, on 0 form(s)
0of 55 forms filed late

Last period with anything received: 2026-08-31. Most often over: Oil & Grease (1).

Reporting

Reports are due about 25 days after each monitoring period ends (the most common figure among AR permits in EPA's filings — check your permit).

Limits in force (92)

OutfallParameterStatisticLimitMonths
001Oxygen demand, chem. [low level] [COD]MO AVG report only all year
001Oxygen demand, chem. [low level] [COD]DAILY MX report only all year
001Oxygen demand, chem. [low level] [COD]MO AVG report only all year
001Oxygen demand, chem. [low level] [COD]DAILY MX report only all year
001pHMINIMUM >= 6 SU all year
001pHMAXIMUM <= 9 SU all year
001Oil & GreaseMO AVG <= 10 mg/L all year
001Oil & GreaseDAILY MX <= 15 mg/L all year
001Oil & GreaseMO AVG <= 19.6 lb/d all year
001Oil & GreaseDAILY MX <= 29.4 lb/d 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
002Oxygen demand, chem. [low level] [COD]MO AVG report only all year
002Oxygen demand, chem. [low level] [COD]DAILY MX report only all year
002Oxygen demand, chem. [low level] [COD]MO AVG report only all year
002Oxygen demand, chem. [low level] [COD]DAILY MX report only all year
002pHMINIMUM >= 6 SU all year
002pHMAXIMUM <= 9 SU all year
002Oil & GreaseMO AVG <= 10 mg/L all year
002Oil & GreaseDAILY MX <= 15 mg/L all year
002Oil & GreaseMO AVG <= 120.1 lb/d all year
002Oil & GreaseDAILY MX <= 180.1 lb/d all year
002Flow, in conduit or thru treatment plantMO AVG report only all year
002Flow, in conduit or thru treatment plantDAILY MX report only all year
01ApHMINIMUM >= 6 SU all year
01ApHMAXIMUM <= 9 SU all year
01ASolids, total suspendedMO AVG <= 30 mg/L all year
01ASolids, total suspendedDAILY MX <= 100 mg/L all year
01ASolids, total suspendedMO AVG <= 4.8 lb/d all year
01ASolids, total suspendedDAILY MX <= 16 lb/d all year
01AOil & GreaseMO AVG <= 15 mg/L all year
01AOil & GreaseDAILY MX <= 20 mg/L all year
01AOil & GreaseMO AVG <= 2.4 lb/d all year
01AOil & GreaseDAILY MX <= 3.2 lb/d all year
01AFlow, in conduit or thru treatment plantMO AVG report only all year
01AFlow, in conduit or thru treatment plantDAILY MX report only all year
01BpHMINIMUM >= 6 SU all year
01BpHMAXIMUM <= 9 SU all year
01BZinc, total recoverableMO AVG <= 0 mg/L all year
01BZinc, total recoverableDAILY MX <= 0 mg/L all year
01BZinc, total recoverableMO AVG <= 0 lb/d all year
01BZinc, total recoverableDAILY MX <= 0 lb/d all year
01BChromium, total recoverableMO AVG <= 0 mg/L all year
01BChromium, total recoverableDAILY MX <= 0 mg/L all year
01BChromium, total recoverableMO AVG <= 0 lb/d all year
01BChromium, total recoverableDAILY MX <= 0 lb/d all year
01BFlow, in conduit or thru treatment plantMO AVG report only all year
01BFlow, in conduit or thru treatment plantDAILY MX report only all year
01BChlorine, free availableMO AVG <= .2 mg/L all year
01BChlorine, free availableDAILY MX <= .5 mg/L all year
01BChlorine, free availableMO AVG <= .03 lb/d all year
01BChlorine, free availableDAILY MX <= .06 lb/d all year
TX1Whole effluent toxicity - retest #17 DA AVG report only all year
TX1Whole effluent toxicity - retest #27 DA AVG report only all year
TX1WET, sublethal retest #17 DA AVG report only all year
TX1WET, sublethal retest #27 DA AVG report only all year
TX1Whole Effluent Toxicity - Retest #37 DA AVG report only all year
TX1Whole Effluent Toxicity, Sub-Lethal Retest #37 DA AVG report only all year
TX1Pass/Fail Static Renewal 7 Day Chronic Ceriodaphnia dubia7 DA AVG report only all year
TX1Pass/Fail Static Renewal 7Day Chronic Pimephales promelas7 DA AVG report only all year
TX1Low Flow Pass/Fail Survival Test Static Renewal 7 Day Chronic Ceriodaphnia dubia7 DA AVG report only all year
TX1Low Flow Pass/Fail Survival Test Static Renewal 7 Day Chronic Pimephales promelas7 DA AVG report only all year
TX1NOEC Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia7 DA AVG report only all year
TX1NOEC Lethal Static Renewal 7 Day Chronic Pimephales promelas7 DA AVG report only all year
TX1NOEC Sub-Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia7 DA AVG report only all year
TX1NOEC Sub-Lethal Static Renewal 7 Day Chronic Pimephales promelas7 DA AVG report only all year
TX1Coef Of Var Static Renewal 7Day Chronic Ceriodaphnia dubia7 DA AVG report only all year
TX1Coef Of Var Static Renewal 7Day Chronic Pimephales promelas7 DA AVG report only all year
TX2Whole effluent toxicity - retest #148HR MIN report only all year
TX2Whole effluent toxicity - retest #148HR MIN report only all year
TX2Whole effluent toxicity - retest #248HR MIN report only all year
TX2Whole effluent toxicity - retest #248HR MIN report only all year
TX2WET, sublethal retest #148HR MIN report only all year
TX2WET, sublethal retest #148HR MIN report only all year
TX2WET, sublethal retest #248HR MIN report only all year
TX2WET, sublethal retest #248HR MIN report only all year
TX2Whole Effluent Toxicity - Retest #348HR MIN report only all year
TX2Whole Effluent Toxicity - Retest #348HR MIN report only all year
TX2Whole Effluent Toxicity, Sub-Lethal Retest #348HR MIN report only all year
TX2Whole Effluent Toxicity, Sub-Lethal Retest #348HR MIN report only all year
TX2Low Flow Pass/Fail Static Renewal 48Hr Acute Daphnia pulex48HR MIN report only all year
TX2Low Flow Pass/Fail Static Renewal 48Hr Acute Daphnia pulex48HR MIN report only all year
TX2LF Pass/Fail Static Renewal 48Hr Acute Pimephales promelas48HR MIN report only all year
TX2LF Pass/Fail Static Renewal 48Hr Acute Pimephales promelas48HR MIN report only all year
TX2NOAEC Lethal Statis Renewal 48 Hr Acute Daphnia pulex48HR MIN report only all year
TX2NOAEC Lethal Statis Renewal 48 Hr Acute Daphnia pulex48HR MIN report only all year
TX2NOAEC Lethal Static Renewal 48Hr acute Pimephales promelas48HR MIN report only all year
TX2NOAEC Lethal Static Renewal 48Hr acute Pimephales promelas48HR MIN report only all year
TX2Coef Of Var Static Renewal 48Hr Acute D. pulex48HR MIN report only all year
TX2Coef Of Var Static Renewal 48Hr Acute D. pulex48HR MIN report only all year
TX2Coef Of Var Static Renewal 48Hr Acute D. pulex48HR MIN report only all year
TX2Coef Of Var Static Renewal 48Hr Acute Pimephales promelas48HR MIN 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