Clean Water Act discharge permit · NPDES CA0079898

GRASS VALLEY WWTP, Grass Valley, CA: NPDES CA0079898 discharge permit, effluent exceedances, inspections, penalties

Administratively continuedPermit status
MajorDischarger class
150Pollutants under a numeric limit
18Pollutants with an effluent exceedance

GRASS VALLEY WWTP, held by GRASS VALLEY, CITY OF, holds NPDES permit CA0079898, which discharges to Wolf Creek. EPA’s file records it issued June 12, 2009 and expiring June 12, 2014. The status and dates are as EPA’s permit file stood when Velarion loaded it (October 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.

Identity

Facility as filed	GRASS VALLEY WWTP
Permittee as filed	GRASS VALLEY, CITY OF
NPDES ID	CA0079898
Permit status	Administratively continued (past its expiration date and still in force until reissued)
Permit type	Individual permit
Discharger class	Major discharger
Facility type	Publicly owned treatment works
Program	Publicly owned treatment works
Issued	June 12, 2009
Expiration date	June 12, 2014
Address	Grass Valley, CA 95945
Receiving water	WOLF CREEK
Subwatershed	Rattlesnake Creek-Wolf Creek (HUC 180201260202)
SIC	4952 – Sewerage Systems

Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download.

Effluent limits and exceedances

159Pollutants on file
150Under a numeric limit
156With a violation of any kind
18With 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 159 are shown.

Pollutant or measure	Limits	Violations, any kind	Effluent exceedances	Latest exceedance	Largest exceedance, as filed
Chloroform	1	87	81	June 30, 2009	3,536% over the limit
Coliform, total general	4	35	15	December 31, 2021	2,009% over the limit
Manganese, total recoverable	5	23	15	May 31, 2007	344% over the limit
Nitrite + Nitrate total [as N]	12	23	11	November 30, 2016	40% over the limit
Copper, total recoverable	1	12	9	September 30, 2008	167% over the limit
BOD, 5-day, 20 deg. C	7	49	6	May 31, 2019	430% over the limit
pH	4	23	6	July 31, 2021
Aluminum, total recoverable	1	18	6	August 31, 2007	561% over the limit
Nitrogen, ammonia total [as N]	4	38	4	May 31, 2021	183% over the limit
Solids, total suspended	7	59	3	February 28, 2017	115% over the limit
Cyanide, total [as CN]	6	37	3	December 31, 2017	1,500% over the limit
Surfactants [MBAS]	5	18	3	May 31, 2010	46,225% over the limit
Nitrogen, nitrite total [as N]	4	27	1	December 31, 2015	14% over the limit
Mercury, total recoverable	4	25	1	September 30, 2004	5,320% over the limit
Dichlorobromomethane	6	14	1	June 30, 2009	515% over the limit
Specific conductance	2	14	1	December 31, 2009	6,651% over the limit
Lead, total recoverable	1	10	1	November 30, 2007	3,114% over the limit
Zinc, total recoverable	1	4	1	October 31, 2004	4,001% over the limit
Chlorine, total residual	2	57	0
Flow, in conduit or thru treatment plant	4	18	0
Dibromochloromethane	6	13	0
Solids, settleable	1	10	0
Solids, total dissolved	1	10	0
Temperature, water deg. fahrenheit	1	9	0
TU Static Renewal 7-Day Chronic Pimphales promelas	2	5	0
Carbon tetrachloride	1	5	0
Turbidity	2	4	0
BOD, 5-day, percent removal	1	4	0
Solids, suspended percent removal	1	4	0
TU Static 4 Day Chronic Raphidocelis subcapitata (formerly Selenastrum capricornutum)	2	3	0
TU Static Renewal 7-Day Chronic Ceriodaphnia dubia	2	3	0
Hardness, total [as CaCO3]	1	3	0
Methyl tert-butyl ether [MTBE]	0	3	0
Arsenic, total recoverable	1	2	0
Selenium, total recoverable	1	2	0
Thallium, total recoverable	1	2	0
Beryllium, total recoverable [as Be]	1	2	0
Nickel, total recoverable	1	2	0
Silver total recoverable	1	2	0
Cadmium, total recoverable	1	2	0
Antimony, total recoverable	1	2	0
2-Methyl-4,6-dinitrophenol	1	2	0
1,2-Dichloroethane	1	2	0
Bromoform	1	2	0
Toluene	1	2	0
Benzene	1	2	0
.delta.-BHC	1	2	0
Acenaphthylene	1	2	0
Acenaphthene	1	2	0
Acrolein	1	2	0
Acrylonitrile	1	2	0
Anthracene	1	2	0
Benzo[b]fluoranthene	1	2	0
Benzo[k]fluoranthene	1	2	0
Benzo[a]pyrene	1	2	0
Bis[2-chloroethyl] ether	1	2	0
Bis[2-chloroethoxy]methane	1	2	0
Bis[2-chloroisopropyl] ether	1	2	0
Butyl benzyl phthalate	1	2	0
Chlorobenzene	1	2	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 CA0079898.

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 CA0079898 there.

Nearby on the register

Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.