TransAlta Centralia Mining LLC — NPDES permit WA0037338: limits, due date and EPA's record

Bituminous Coal And Lignite - Surface, major discharger, Centralia, Washington. NPDES permit WA0037338 expired Oct 31, 2022; its limits still apply. Last 12 months: over a limit once (last April 2026), 7 required values missing, 7 of 156 reports late. Source: EPA ECHO, Oct 22, 2026.

Last 12 months (Oct 1, 2025 – Sep 30, 2026)

Period ending	Parameter	Reported	Limit	Over by
April 2026	Solids, total suspended, monthly average	27.5	≤ 20 mg/L	38%

Limits in force (257)

Parameter	Statistic	Limit	Months	Outfall
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	001
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	001
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	001
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	001
Turbidity	monthly average	≤ 25 NTU	all year	001
Turbidity	monthly average	≤ 25 NTU	all year	001
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	001
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	001
pH	maximum	≤ 9 SU	all year	001
pH	maximum	≤ 9 SU	all year	001
pH	minimum	≥ 6 SU	all year	001
pH	minimum	≥ 6 SU	all year	001
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	001
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	001
Solids, total suspended	monthly average	≤ 20 mg/L	all year	001
Solids, total suspended	monthly average	≤ 20 mg/L	all year	001
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	001
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	001
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	001
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	001
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	002
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	002
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	002
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	002
Turbidity	monthly average	≤ 25 NTU	all year	002
Turbidity	monthly average	≤ 25 NTU	all year	002
Conductivity	daily maximum	report only (umho/cm) (alert, not enforceable)	all year	002
Conductivity	daily maximum	report only (umho/cm) (alert, not enforceable)	all year	002
Sulfate [as S]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	002
Sulfate [as S]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	002
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	002
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	002
pH	maximum	≤ 9 SU	all year	002
pH	maximum	≤ 9 SU	all year	002
pH	minimum	≥ 6 SU	all year	002
pH	minimum	≥ 6 SU	all year	002
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	002
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	002
Solids, total suspended	monthly average	≤ 20 mg/L	all year	002
Solids, total suspended	monthly average	≤ 20 mg/L	all year	002
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	002
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	002
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	002
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	002
Aluminum, total [as Al]	monthly average	report only (mg/L) (alert, not enforceable)	all year	002
Aluminum, total [as Al]	monthly average	report only (mg/L) (alert, not enforceable)	all year	002
Solids, total dissolved	daily maximum	report only (mg/L) (alert, not enforceable)	all year	002
Solids, total dissolved	daily maximum	report only (mg/L) (alert, not enforceable)	all year	002
Hydrocarbons, total petroleum	daily maximum	≤ 15 mg/L	all year	002
Hydrocarbons, total petroleum	daily maximum	≤ 15 mg/L	all year	002
Hydrocarbons, total petroleum	monthly average	≤ 10 mg/L	all year	002
Hydrocarbons, total petroleum	monthly average	≤ 10 mg/L	all year	002
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	003
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	003
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	003
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	003
Turbidity	monthly average	≤ 25 NTU	all year	003
Turbidity	monthly average	≤ 25 NTU	all year	003
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	003
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	003
pH	maximum	≤ 9 SU	all year	003
pH	maximum	≤ 9 SU	all year	003
pH	minimum	≥ 6 SU	all year	003
pH	minimum	≥ 6 SU	all year	003
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	003
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	003
Solids, total suspended	monthly average	≤ 20 mg/L	all year	003
Solids, total suspended	monthly average	≤ 20 mg/L	all year	003
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	003
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	003
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	003
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	003
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	004
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	004
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	004
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	004
Turbidity	monthly average	≤ 25 NTU	all year	004
Turbidity	monthly average	≤ 25 NTU	all year	004
Conductivity	daily maximum	report only (umho/cm) (alert, not enforceable)	all year	004
Conductivity	daily maximum	report only (umho/cm) (alert, not enforceable)	all year	004
Sulfate [as S]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	004
Sulfate [as S]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	004
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	004
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	004
pH	maximum	≤ 9 SU	all year	004
pH	maximum	≤ 9 SU	all year	004
pH	minimum	≥ 6 SU	all year	004
pH	minimum	≥ 6 SU	all year	004
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	004
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	004
Solids, total suspended	monthly average	≤ 20 mg/L	all year	004
Solids, total suspended	monthly average	≤ 20 mg/L	all year	004
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	004
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	004
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	004
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	004
Aluminum, total [as Al]	monthly average	report only (mg/L) (alert, not enforceable)	all year	004
Aluminum, total [as Al]	monthly average	report only (mg/L) (alert, not enforceable)	all year	004
Solids, total dissolved	daily maximum	report only (mg/L) (alert, not enforceable)	all year	004
Solids, total dissolved	daily maximum	report only (mg/L) (alert, not enforceable)	all year	004
Hydrocarbons, total petroleum	daily maximum	≤ 15 mg/L	all year	004
Hydrocarbons, total petroleum	daily maximum	≤ 15 mg/L	all year	004
Hydrocarbons, total petroleum	monthly average	≤ 10 mg/L	all year	004
Hydrocarbons, total petroleum	monthly average	≤ 10 mg/L	all year	004
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	005
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	005
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	005
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	005
Turbidity	monthly average	≤ 25 NTU	all year	005
Turbidity	monthly average	≤ 25 NTU	all year	005
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	005
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	005
pH	maximum	≤ 9 SU	all year	005
pH	maximum	≤ 9 SU	all year	005
pH	minimum	≥ 6 SU	all year	005
pH	minimum	≥ 6 SU	all year	005
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	005
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	005
Solids, total suspended	monthly average	≤ 20 mg/L	all year	005
Solids, total suspended	monthly average	≤ 20 mg/L	all year	005
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	005
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	005
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	005
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	005
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	006
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	006
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	006
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	006
Turbidity	monthly average	≤ 25 NTU	all year	006
Turbidity	monthly average	≤ 25 NTU	all year	006
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	006
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	006
pH	maximum	≤ 9 SU	all year	006
pH	maximum	≤ 9 SU	all year	006
pH	minimum	≥ 6 SU	all year	006
pH	minimum	≥ 6 SU	all year	006
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	006
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	006
Solids, total suspended	monthly average	≤ 20 mg/L	all year	006
Solids, total suspended	monthly average	≤ 20 mg/L	all year	006
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	006
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	006
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	006
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	006
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	008
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	008
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	008
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	008
Turbidity	monthly average	≤ 25 NTU	all year	008
Turbidity	monthly average	≤ 25 NTU	all year	008
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	008
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	008
pH	maximum	≤ 9 SU	all year	008
pH	maximum	≤ 9 SU	all year	008
pH	minimum	≥ 6 SU	all year	008
pH	minimum	≥ 6 SU	all year	008
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	008
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	008
Solids, total suspended	monthly average	≤ 20 mg/L	all year	008
Solids, total suspended	monthly average	≤ 20 mg/L	all year	008
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	008
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	008
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	008
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	008
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	009
Temperature, water deg. centigrade	daily maximum	≤ 17.5 deg C	all year	009
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	009
Temperature, water deg. centigrade	monthly average	≤ 17.5 deg C	all year	009
Turbidity	monthly average	≤ 50 NTU	all year	009
Turbidity	monthly average	≤ 50 NTU	all year	009
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	009
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	009
pH	maximum	≤ 9 SU	all year	009
pH	maximum	≤ 9 SU	all year	009
pH	minimum	≥ 6 SU	all year	009
pH	minimum	≥ 6 SU	all year	009
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	009
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	009
Solids, total suspended	monthly average	≤ 20 mg/L	all year	009
Solids, total suspended	monthly average	≤ 20 mg/L	all year	009
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	009
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	009
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	009
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	009
Temperature, water deg. centigrade	daily maximum	report only (deg C) (alert, not enforceable)	all year	010
Temperature, water deg. centigrade	daily maximum	report only (deg C) (alert, not enforceable)	all year	010
Temperature, water deg. centigrade	monthly average	report only (deg C) (alert, not enforceable)	all year	010
Temperature, water deg. centigrade	monthly average	report only (deg C) (alert, not enforceable)	all year	010
Turbidity	monthly average	≤ 50 NTU	all year	010
Turbidity	monthly average	≤ 50 NTU	all year	010
Conductivity	daily maximum	report only (umho/cm) (alert, not enforceable)	all year	010
Conductivity	daily maximum	report only (umho/cm) (alert, not enforceable)	all year	010
Sulfate [as S]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	010
Sulfate [as S]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	010
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	010
Oxygen, dissolved [DO]	minimum	≥ 8 mg/L	all year	010
pH	maximum	≤ 9 SU	all year	010
pH	maximum	≤ 9 SU	all year	010
pH	minimum	≥ 6 SU	all year	010
pH	minimum	≥ 6 SU	all year	010
Solids, total suspended	daily maximum	report only (mg/L) (alert, not enforceable)	all year	010
Solids, total suspended	daily maximum	report only (mg/L) (alert, not enforceable)	all year	010
Solids, total suspended	monthly average	report only (mg/L) (alert, not enforceable)	all year	010
Solids, total suspended	monthly average	report only (mg/L) (alert, not enforceable)	all year	010
Solids, settleable	daily maximum	≤ .5 mL/L	all year	010
Solids, settleable	daily maximum	≤ .5 mL/L	all year	010
Solids, settleable	monthly average	report only (mL/L)	all year	010
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	010
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	010
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	010
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	010
Manganese, total [as Mn]	daily maximum	≤ 4 mg/L	all year	010
Manganese, total [as Mn]	daily maximum	≤ 4 mg/L	all year	010
Manganese, total [as Mn]	monthly average	≤ 2 mg/L	all year	010
Manganese, total [as Mn]	monthly average	≤ 2 mg/L	all year	010
Solids, total dissolved	daily maximum	report only (mg/L) (alert, not enforceable)	all year	010
Solids, total dissolved	daily maximum	report only (mg/L) (alert, not enforceable)	all year	010
Temperature, water deg. centigrade	daily maximum	≤ 16 deg C	all year	011
Temperature, water deg. centigrade	daily maximum	≤ 16 deg C	all year	011
Temperature, water deg. centigrade	monthly average	≤ 16 deg C	all year	011
Temperature, water deg. centigrade	monthly average	≤ 16 deg C	all year	011
Turbidity	monthly average	≤ 25 NTU	all year	011
Turbidity	monthly average	≤ 25 NTU	all year	011
Oxygen, dissolved [DO]	minimum	≥ 9.5 mg/L	all year	011
Oxygen, dissolved [DO]	minimum	≥ 9.5 mg/L	all year	011
pH	maximum	≤ 9 SU	all year	011
pH	maximum	≤ 9 SU	all year	011
pH	minimum	≥ 6 SU	all year	011
pH	minimum	≥ 6 SU	all year	011
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	011
Solids, total suspended	daily maximum	≤ 40 mg/L	all year	011
Solids, total suspended	monthly average	≤ 20 mg/L	all year	011
Solids, total suspended	monthly average	≤ 20 mg/L	all year	011
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	011
Iron, total [as Fe]	daily maximum	≤ 3.5 mg/L	all year	011
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	011
Iron, total [as Fe]	monthly average	≤ 3.5 mg/L	all year	011
pH	maximum	report only (SU) (alert, not enforceable)	all year	012
pH	maximum	report only (SU) (alert, not enforceable)	all year	012
pH	minimum	report only (SU) (alert, not enforceable)	all year	012
pH	minimum	report only (SU) (alert, not enforceable)	all year	012
Solids, total suspended	daily maximum	report only (mg/L) (alert, not enforceable)	all year	012
Solids, total suspended	daily maximum	report only (mg/L) (alert, not enforceable)	all year	012
Solids, total suspended	monthly average	report only (mg/L) (alert, not enforceable)	all year	012
Solids, total suspended	monthly average	report only (mg/L) (alert, not enforceable)	all year	012
Iron, total [as Fe]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	012
Iron, total [as Fe]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	012
Iron, total [as Fe]	monthly average	report only (mg/L) (alert, not enforceable)	all year	012
Iron, total [as Fe]	monthly average	report only (mg/L) (alert, not enforceable)	all year	012
Manganese, total [as Mn]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	012
Manganese, total [as Mn]	daily maximum	report only (mg/L) (alert, not enforceable)	all year	012
Manganese, total [as Mn]	monthly average	report only (mg/L) (alert, not enforceable)	all year	012
Manganese, total [as Mn]	monthly average	report only (mg/L) (alert, not enforceable)	all year	012
Flow	daily maximum	report only (cfs) (alert, not enforceable)	all year	UHNC
Flow	daily maximum	report only (cfs) (alert, not enforceable)	all year	UHNC
Flow	monthly average	report only (cfs) (alert, not enforceable)	all year	UHNC
Flow	monthly average	report only (cfs) (alert, not enforceable)	all year	UHNC

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/WA0037338 · MCP: https://passage-data.com/mcp