Clean Water Act discharge permit · NPDES CA0079430
MARIPOSA WWTF, Mariposa, CA: NPDES CA0079430 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MinorDischarger class
- 155Pollutants under a numeric limit
- 2Pollutants with an effluent exceedance
MARIPOSA WWTF, held by MARIPOSA PUD, holds NPDES permit CA0079430, which discharges to Mariposa Creek. EPA’s file records it issued December 6, 2007 and expiring December 4, 2012. The status and dates are as EPA’s permit file stood when Velarion loaded it (September 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
Identity
| Facility as filed | MARIPOSA WWTF |
|---|---|
| Permittee as filed | MARIPOSA PUD |
| NPDES ID | CA0079430 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Individual permit |
| Discharger class | Minor discharger |
| Facility type | Publicly owned treatment works |
| Program | Publicly owned treatment works |
| Issued | December 6, 2007 |
| Expiration date | December 4, 2012 |
| Address | Mariposa, CA 95338 |
| Receiving water | MARIPOSA CREEK |
| Subwatershed | Stockton Creek-Mariposa Creek (HUC 180400011502) |
Cited to the EPA ICIS-NPDES permit file (ECHO download).
Effluent limits and exceedances
- 158Pollutants on file
- 155Under a numeric limit
- 11With a violation of any kind
- 2With an effluent exceedance
An effluent exceedance is a discharge monitoring report value over the permit’s numeric limit (EPA’s violation code E90). A violation of any kind also counts a report not filed. Each row is EPA’s own count for that pollutant; the 60 with the most exceedances of 158 are shown.
| Pollutant or measure | Limits | Violations, any kind | Effluent exceedances | Latest exceedance | Largest exceedance, as filed |
|---|---|---|---|---|---|
| Nitrogen, ammonia total [as N] | 1 | 5 | 5 | June 30, 2020 | 852% over the limit |
| Solids, total suspended | 12 | 1 | 1 | March 31, 2021 | 99,999% over the limit |
| Dichlorobromomethane | 5 | 2 | 0 | ||
| Chlorine, total residual | 2 | 2 | 0 | ||
| Dibromochloromethane | 1 | 2 | 0 | ||
| Bromoform | 1 | 1 | 0 | ||
| Chloroform | 1 | 1 | 0 | ||
| Methyl bromide [Bromomethane] | 1 | 1 | 0 | ||
| Temperature, water deg. centigrade | 0 | 1 | 0 | ||
| Nitrogen, nitrite total [as N] | 0 | 1 | 0 | ||
| Trihalomethane, tot. | 0 | 1 | 0 | ||
| BOD, 5-day, 20 deg. C | 12 | 0 | 0 | ||
| Flow, in conduit or thru treatment plant | 4 | 0 | 0 | ||
| Coliform, total general | 4 | 0 | 0 | ||
| Turbidity | 3 | 0 | 0 | ||
| Zinc, total recoverable | 3 | 0 | 0 | ||
| Copper, total recoverable | 3 | 0 | 0 | ||
| pH | 2 | 0 | 0 | ||
| Solids, settleable | 2 | 0 | 0 | ||
| Nitrogen, nitrate total [as N] | 2 | 0 | 0 | ||
| % Survival Static Renewal 96Hr Acute Pimephales promelas | 2 | 0 | 0 | ||
| TU Static 4 Day Chronic Raphidocelis subcapitata (formerly Selenastrum capricornutum) | 2 | 0 | 0 | ||
| TU Static Renewal 7-Day Chronic Ceriodaphnia dubia | 2 | 0 | 0 | ||
| TU Static Renewal 7-Day Chronic Pimphales promelas | 2 | 0 | 0 | ||
| Temperature, water deg. fahrenheit | 1 | 0 | 0 | ||
| Specific conductance | 1 | 0 | 0 | ||
| Alkalinity, total [as CaCO3] | 1 | 0 | 0 | ||
| Phosphorus, total [as P] | 1 | 0 | 0 | ||
| Cyanide, total [as CN] | 1 | 0 | 0 | ||
| Hardness, total [as CaCO3] | 1 | 0 | 0 | ||
| Calcium, total [as Ca] | 1 | 0 | 0 | ||
| Magnesium, total recoverable | 1 | 0 | 0 | ||
| Sodium, total [as Na] | 1 | 0 | 0 | ||
| Potassium, total [as K] | 1 | 0 | 0 | ||
| Chloride [as Cl] | 1 | 0 | 0 | ||
| Arsenic, total recoverable | 1 | 0 | 0 | ||
| Iron, total recoverable | 1 | 0 | 0 | ||
| Selenium, total recoverable | 1 | 0 | 0 | ||
| Thallium, total recoverable | 1 | 0 | 0 | ||
| Beryllium, total recoverable [as Be] | 1 | 0 | 0 | ||
| Boron, total recoverable | 1 | 0 | 0 | ||
| Chromium, hexavalent [as Cr] | 1 | 0 | 0 | ||
| Chromium, trivalent [as Cr] | 1 | 0 | 0 | ||
| Nickel, total recoverable | 1 | 0 | 0 | ||
| Silver total recoverable | 1 | 0 | 0 | ||
| Cadmium, total recoverable | 1 | 0 | 0 | ||
| Lead, total recoverable | 1 | 0 | 0 | ||
| Antimony, total recoverable | 1 | 0 | 0 | ||
| 2-Methyl-4,6-dinitrophenol | 1 | 0 | 0 | ||
| Manganese, total recoverable | 1 | 0 | 0 | ||
| Carbon tetrachloride | 1 | 0 | 0 | ||
| 1,2-Dichloroethane | 1 | 0 | 0 | ||
| Toluene | 1 | 0 | 0 | ||
| Benzene | 1 | 0 | 0 | ||
| .delta.-BHC | 1 | 0 | 0 | ||
| Acenaphthylene | 1 | 0 | 0 | ||
| Acenaphthene | 1 | 0 | 0 | ||
| Acrolein | 1 | 0 | 0 | ||
| Acrylonitrile | 1 | 0 | 0 | ||
| Anthracene | 1 | 0 | 0 |
Cited to the EPA ICIS-NPDES limits and effluent violations files (ECHO download); up to 60 rows shown, most exceedances first.
Inspections, violations and enforcement
- 0Single-event violations
EPA’s single-event violation file, as loaded, holds no violation for NPDES CA0079430.
Velarion’s copy of EPA’s ICIS-NPDES files does not include the inspections, formal enforcement actions and informal enforcement actions files, so this page shows none of them. EPA’s free Detailed Facility Report on ECHO lists this permit’s inspections, enforcement actions and penalties.
Cited to the EPA ICIS-NPDES violation, inspection and enforcement files (ECHO download); up to 50 rows of each shown, newest first.
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EPA publishes a free Detailed Facility Report for every permit on ECHO: its compliance status quarter by quarter, its inspections, and its enforcement actions and penalties. EPA also sends free notices of new inspections and enforcement actions through ECHO Notify; enter NPDES ID CA0079430 there.
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Figures from EPA’s ICIS-NPDES download, loaded September 14, 2026.